Restoring authorship annotation for <orivej@yandex-team.ru>. Commit 1 of 2.

1 files changed, 2134 insertions, 2134 deletions

diff --git a/contrib/libs/llvm12/lib/Transforms/Scalar/LICM.cpp b/contrib/libs/llvm12/lib/Transforms/Scalar/LICM.cpp
index d2b4ba296f..5276b77f8c 100644
--- a/contrib/libs/llvm12/lib/Transforms/Scalar/LICM.cpp
+++ b/contrib/libs/llvm12/lib/Transforms/Scalar/LICM.cpp
@@ -1,17 +1,17 @@
-//===-- LICM.cpp - Loop Invariant Code Motion Pass ------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// This pass performs loop invariant code motion, attempting to remove as much
-// code from the body of a loop as possible.  It does this by either hoisting
-// code into the preheader block, or by sinking code to the exit blocks if it is
-// safe.  This pass also promotes must-aliased memory locations in the loop to
-// live in registers, thus hoisting and sinking "invariant" loads and stores.
-//
+//===-- LICM.cpp - Loop Invariant Code Motion Pass ------------------------===// 
+// 
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 
+// See https://llvm.org/LICENSE.txt for license information. 
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 
+// 
+//===----------------------------------------------------------------------===// 
+// 
+// This pass performs loop invariant code motion, attempting to remove as much 
+// code from the body of a loop as possible.  It does this by either hoisting 
+// code into the preheader block, or by sinking code to the exit blocks if it is 
+// safe.  This pass also promotes must-aliased memory locations in the loop to 
+// live in registers, thus hoisting and sinking "invariant" loads and stores. 
+// 
 // Hoisting operations out of loops is a canonicalization transform.  It
 // enables and simplifies subsequent optimizations in the middle-end.
 // Rematerialization of hoisted instructions to reduce register pressure is the
@@ -19,223 +19,223 @@
 // register pressure and also handles other optimizations than LICM that
 // increase live-ranges.
 //
-// This pass uses alias analysis for two purposes:
-//
-//  1. Moving loop invariant loads and calls out of loops.  If we can determine
-//     that a load or call inside of a loop never aliases anything stored to,
-//     we can hoist it or sink it like any other instruction.
-//  2. Scalar Promotion of Memory - If there is a store instruction inside of
-//     the loop, we try to move the store to happen AFTER the loop instead of
-//     inside of the loop.  This can only happen if a few conditions are true:
-//       A. The pointer stored through is loop invariant
-//       B. There are no stores or loads in the loop which _may_ alias the
-//          pointer.  There are no calls in the loop which mod/ref the pointer.
-//     If these conditions are true, we can promote the loads and stores in the
-//     loop of the pointer to use a temporary alloca'd variable.  We then use
-//     the SSAUpdater to construct the appropriate SSA form for the value.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Transforms/Scalar/LICM.h"
-#include "llvm/ADT/SetOperations.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/AliasSetTracker.h"
-#include "llvm/Analysis/BasicAliasAnalysis.h"
+// This pass uses alias analysis for two purposes: 
+// 
+//  1. Moving loop invariant loads and calls out of loops.  If we can determine 
+//     that a load or call inside of a loop never aliases anything stored to, 
+//     we can hoist it or sink it like any other instruction. 
+//  2. Scalar Promotion of Memory - If there is a store instruction inside of 
+//     the loop, we try to move the store to happen AFTER the loop instead of 
+//     inside of the loop.  This can only happen if a few conditions are true: 
+//       A. The pointer stored through is loop invariant 
+//       B. There are no stores or loads in the loop which _may_ alias the 
+//          pointer.  There are no calls in the loop which mod/ref the pointer. 
+//     If these conditions are true, we can promote the loads and stores in the 
+//     loop of the pointer to use a temporary alloca'd variable.  We then use 
+//     the SSAUpdater to construct the appropriate SSA form for the value. 
+// 
+//===----------------------------------------------------------------------===// 
+ 
+#include "llvm/Transforms/Scalar/LICM.h" 
+#include "llvm/ADT/SetOperations.h" 
+#include "llvm/ADT/Statistic.h" 
+#include "llvm/Analysis/AliasAnalysis.h" 
+#include "llvm/Analysis/AliasSetTracker.h" 
+#include "llvm/Analysis/BasicAliasAnalysis.h" 
 #include "llvm/Analysis/BlockFrequencyInfo.h"
-#include "llvm/Analysis/CaptureTracking.h"
-#include "llvm/Analysis/ConstantFolding.h"
-#include "llvm/Analysis/GlobalsModRef.h"
-#include "llvm/Analysis/GuardUtils.h"
+#include "llvm/Analysis/CaptureTracking.h" 
+#include "llvm/Analysis/ConstantFolding.h" 
+#include "llvm/Analysis/GlobalsModRef.h" 
+#include "llvm/Analysis/GuardUtils.h" 
 #include "llvm/Analysis/LazyBlockFrequencyInfo.h"
-#include "llvm/Analysis/Loads.h"
-#include "llvm/Analysis/LoopInfo.h"
-#include "llvm/Analysis/LoopIterator.h"
-#include "llvm/Analysis/LoopPass.h"
-#include "llvm/Analysis/MemoryBuiltins.h"
-#include "llvm/Analysis/MemorySSA.h"
-#include "llvm/Analysis/MemorySSAUpdater.h"
-#include "llvm/Analysis/MustExecute.h"
-#include "llvm/Analysis/OptimizationRemarkEmitter.h"
-#include "llvm/Analysis/ScalarEvolution.h"
-#include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
-#include "llvm/Analysis/TargetLibraryInfo.h"
-#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/IR/CFG.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/DataLayout.h"
-#include "llvm/IR/DebugInfoMetadata.h"
-#include "llvm/IR/DerivedTypes.h"
-#include "llvm/IR/Dominators.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/IntrinsicInst.h"
-#include "llvm/IR/LLVMContext.h"
-#include "llvm/IR/Metadata.h"
-#include "llvm/IR/PatternMatch.h"
-#include "llvm/IR/PredIteratorCache.h"
-#include "llvm/InitializePasses.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Scalar/LoopPassManager.h"
-#include "llvm/Transforms/Utils/AssumeBundleBuilder.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/Transforms/Utils/LoopUtils.h"
-#include "llvm/Transforms/Utils/SSAUpdater.h"
-#include <algorithm>
-#include <utility>
-using namespace llvm;
-
-#define DEBUG_TYPE "licm"
-
-STATISTIC(NumCreatedBlocks, "Number of blocks created");
-STATISTIC(NumClonedBranches, "Number of branches cloned");
-STATISTIC(NumSunk, "Number of instructions sunk out of loop");
-STATISTIC(NumHoisted, "Number of instructions hoisted out of loop");
-STATISTIC(NumMovedLoads, "Number of load insts hoisted or sunk");
-STATISTIC(NumMovedCalls, "Number of call insts hoisted or sunk");
-STATISTIC(NumPromoted, "Number of memory locations promoted to registers");
-
-/// Memory promotion is enabled by default.
-static cl::opt<bool>
-    DisablePromotion("disable-licm-promotion", cl::Hidden, cl::init(false),
-                     cl::desc("Disable memory promotion in LICM pass"));
-
-static cl::opt<bool> ControlFlowHoisting(
-    "licm-control-flow-hoisting", cl::Hidden, cl::init(false),
-    cl::desc("Enable control flow (and PHI) hoisting in LICM"));
-
+#include "llvm/Analysis/Loads.h" 
+#include "llvm/Analysis/LoopInfo.h" 
+#include "llvm/Analysis/LoopIterator.h" 
+#include "llvm/Analysis/LoopPass.h" 
+#include "llvm/Analysis/MemoryBuiltins.h" 
+#include "llvm/Analysis/MemorySSA.h" 
+#include "llvm/Analysis/MemorySSAUpdater.h" 
+#include "llvm/Analysis/MustExecute.h" 
+#include "llvm/Analysis/OptimizationRemarkEmitter.h" 
+#include "llvm/Analysis/ScalarEvolution.h" 
+#include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h" 
+#include "llvm/Analysis/TargetLibraryInfo.h" 
+#include "llvm/Analysis/ValueTracking.h" 
+#include "llvm/IR/CFG.h" 
+#include "llvm/IR/Constants.h" 
+#include "llvm/IR/DataLayout.h" 
+#include "llvm/IR/DebugInfoMetadata.h" 
+#include "llvm/IR/DerivedTypes.h" 
+#include "llvm/IR/Dominators.h" 
+#include "llvm/IR/Instructions.h" 
+#include "llvm/IR/IntrinsicInst.h" 
+#include "llvm/IR/LLVMContext.h" 
+#include "llvm/IR/Metadata.h" 
+#include "llvm/IR/PatternMatch.h" 
+#include "llvm/IR/PredIteratorCache.h" 
+#include "llvm/InitializePasses.h" 
+#include "llvm/Support/CommandLine.h" 
+#include "llvm/Support/Debug.h" 
+#include "llvm/Support/raw_ostream.h" 
+#include "llvm/Transforms/Scalar.h" 
+#include "llvm/Transforms/Scalar/LoopPassManager.h" 
+#include "llvm/Transforms/Utils/AssumeBundleBuilder.h" 
+#include "llvm/Transforms/Utils/BasicBlockUtils.h" 
+#include "llvm/Transforms/Utils/Local.h" 
+#include "llvm/Transforms/Utils/LoopUtils.h" 
+#include "llvm/Transforms/Utils/SSAUpdater.h" 
+#include <algorithm> 
+#include <utility> 
+using namespace llvm; 
+ 
+#define DEBUG_TYPE "licm" 
+ 
+STATISTIC(NumCreatedBlocks, "Number of blocks created"); 
+STATISTIC(NumClonedBranches, "Number of branches cloned"); 
+STATISTIC(NumSunk, "Number of instructions sunk out of loop"); 
+STATISTIC(NumHoisted, "Number of instructions hoisted out of loop"); 
+STATISTIC(NumMovedLoads, "Number of load insts hoisted or sunk"); 
+STATISTIC(NumMovedCalls, "Number of call insts hoisted or sunk"); 
+STATISTIC(NumPromoted, "Number of memory locations promoted to registers"); 
+ 
+/// Memory promotion is enabled by default. 
+static cl::opt<bool> 
+    DisablePromotion("disable-licm-promotion", cl::Hidden, cl::init(false), 
+                     cl::desc("Disable memory promotion in LICM pass")); 
+ 
+static cl::opt<bool> ControlFlowHoisting( 
+    "licm-control-flow-hoisting", cl::Hidden, cl::init(false), 
+    cl::desc("Enable control flow (and PHI) hoisting in LICM")); 
+ 
 static cl::opt<unsigned> HoistSinkColdnessThreshold(
     "licm-coldness-threshold", cl::Hidden, cl::init(4),
     cl::desc("Relative coldness Threshold of hoisting/sinking destination "
              "block for LICM to be considered beneficial"));
 
-static cl::opt<uint32_t> MaxNumUsesTraversed(
-    "licm-max-num-uses-traversed", cl::Hidden, cl::init(8),
-    cl::desc("Max num uses visited for identifying load "
-             "invariance in loop using invariant start (default = 8)"));
-
-// Default value of zero implies we use the regular alias set tracker mechanism
-// instead of the cross product using AA to identify aliasing of the memory
-// location we are interested in.
-static cl::opt<int>
-LICMN2Theshold("licm-n2-threshold", cl::Hidden, cl::init(0),
-               cl::desc("How many instruction to cross product using AA"));
-
-// Experimental option to allow imprecision in LICM in pathological cases, in
-// exchange for faster compile. This is to be removed if MemorySSA starts to
-// address the same issue. This flag applies only when LICM uses MemorySSA
-// instead on AliasSetTracker. LICM calls MemorySSAWalker's
-// getClobberingMemoryAccess, up to the value of the Cap, getting perfect
-// accuracy. Afterwards, LICM will call into MemorySSA's getDefiningAccess,
-// which may not be precise, since optimizeUses is capped. The result is
-// correct, but we may not get as "far up" as possible to get which access is
-// clobbering the one queried.
-cl::opt<unsigned> llvm::SetLicmMssaOptCap(
-    "licm-mssa-optimization-cap", cl::init(100), cl::Hidden,
-    cl::desc("Enable imprecision in LICM in pathological cases, in exchange "
-             "for faster compile. Caps the MemorySSA clobbering calls."));
-
-// Experimentally, memory promotion carries less importance than sinking and
-// hoisting. Limit when we do promotion when using MemorySSA, in order to save
-// compile time.
-cl::opt<unsigned> llvm::SetLicmMssaNoAccForPromotionCap(
-    "licm-mssa-max-acc-promotion", cl::init(250), cl::Hidden,
-    cl::desc("[LICM & MemorySSA] When MSSA in LICM is disabled, this has no "
-             "effect. When MSSA in LICM is enabled, then this is the maximum "
-             "number of accesses allowed to be present in a loop in order to "
-             "enable memory promotion."));
-
-static bool inSubLoop(BasicBlock *BB, Loop *CurLoop, LoopInfo *LI);
-static bool isNotUsedOrFreeInLoop(const Instruction &I, const Loop *CurLoop,
-                                  const LoopSafetyInfo *SafetyInfo,
-                                  TargetTransformInfo *TTI, bool &FreeInLoop);
-static void hoist(Instruction &I, const DominatorTree *DT, const Loop *CurLoop,
-                  BasicBlock *Dest, ICFLoopSafetyInfo *SafetyInfo,
-                  MemorySSAUpdater *MSSAU, ScalarEvolution *SE,
-                  OptimizationRemarkEmitter *ORE);
-static bool sink(Instruction &I, LoopInfo *LI, DominatorTree *DT,
+static cl::opt<uint32_t> MaxNumUsesTraversed( 
+    "licm-max-num-uses-traversed", cl::Hidden, cl::init(8), 
+    cl::desc("Max num uses visited for identifying load " 
+             "invariance in loop using invariant start (default = 8)")); 
+ 
+// Default value of zero implies we use the regular alias set tracker mechanism 
+// instead of the cross product using AA to identify aliasing of the memory 
+// location we are interested in. 
+static cl::opt<int> 
+LICMN2Theshold("licm-n2-threshold", cl::Hidden, cl::init(0), 
+               cl::desc("How many instruction to cross product using AA")); 
+ 
+// Experimental option to allow imprecision in LICM in pathological cases, in 
+// exchange for faster compile. This is to be removed if MemorySSA starts to 
+// address the same issue. This flag applies only when LICM uses MemorySSA 
+// instead on AliasSetTracker. LICM calls MemorySSAWalker's 
+// getClobberingMemoryAccess, up to the value of the Cap, getting perfect 
+// accuracy. Afterwards, LICM will call into MemorySSA's getDefiningAccess, 
+// which may not be precise, since optimizeUses is capped. The result is 
+// correct, but we may not get as "far up" as possible to get which access is 
+// clobbering the one queried. 
+cl::opt<unsigned> llvm::SetLicmMssaOptCap( 
+    "licm-mssa-optimization-cap", cl::init(100), cl::Hidden, 
+    cl::desc("Enable imprecision in LICM in pathological cases, in exchange " 
+             "for faster compile. Caps the MemorySSA clobbering calls.")); 
+ 
+// Experimentally, memory promotion carries less importance than sinking and 
+// hoisting. Limit when we do promotion when using MemorySSA, in order to save 
+// compile time. 
+cl::opt<unsigned> llvm::SetLicmMssaNoAccForPromotionCap( 
+    "licm-mssa-max-acc-promotion", cl::init(250), cl::Hidden, 
+    cl::desc("[LICM & MemorySSA] When MSSA in LICM is disabled, this has no " 
+             "effect. When MSSA in LICM is enabled, then this is the maximum " 
+             "number of accesses allowed to be present in a loop in order to " 
+             "enable memory promotion.")); 
+ 
+static bool inSubLoop(BasicBlock *BB, Loop *CurLoop, LoopInfo *LI); 
+static bool isNotUsedOrFreeInLoop(const Instruction &I, const Loop *CurLoop, 
+                                  const LoopSafetyInfo *SafetyInfo, 
+                                  TargetTransformInfo *TTI, bool &FreeInLoop); 
+static void hoist(Instruction &I, const DominatorTree *DT, const Loop *CurLoop, 
+                  BasicBlock *Dest, ICFLoopSafetyInfo *SafetyInfo, 
+                  MemorySSAUpdater *MSSAU, ScalarEvolution *SE, 
+                  OptimizationRemarkEmitter *ORE); 
+static bool sink(Instruction &I, LoopInfo *LI, DominatorTree *DT, 
                  BlockFrequencyInfo *BFI, const Loop *CurLoop,
                  ICFLoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU,
                  OptimizationRemarkEmitter *ORE);
-static bool isSafeToExecuteUnconditionally(Instruction &Inst,
-                                           const DominatorTree *DT,
-                                           const Loop *CurLoop,
-                                           const LoopSafetyInfo *SafetyInfo,
-                                           OptimizationRemarkEmitter *ORE,
-                                           const Instruction *CtxI = nullptr);
-static bool pointerInvalidatedByLoop(MemoryLocation MemLoc,
-                                     AliasSetTracker *CurAST, Loop *CurLoop,
-                                     AAResults *AA);
-static bool pointerInvalidatedByLoopWithMSSA(MemorySSA *MSSA, MemoryUse *MU,
+static bool isSafeToExecuteUnconditionally(Instruction &Inst, 
+                                           const DominatorTree *DT, 
+                                           const Loop *CurLoop, 
+                                           const LoopSafetyInfo *SafetyInfo, 
+                                           OptimizationRemarkEmitter *ORE, 
+                                           const Instruction *CtxI = nullptr); 
+static bool pointerInvalidatedByLoop(MemoryLocation MemLoc, 
+                                     AliasSetTracker *CurAST, Loop *CurLoop, 
+                                     AAResults *AA); 
+static bool pointerInvalidatedByLoopWithMSSA(MemorySSA *MSSA, MemoryUse *MU, 
                                              Loop *CurLoop, Instruction &I,
-                                             SinkAndHoistLICMFlags &Flags);
+                                             SinkAndHoistLICMFlags &Flags); 
 static bool pointerInvalidatedByBlockWithMSSA(BasicBlock &BB, MemorySSA &MSSA,
                                               MemoryUse &MU);
-static Instruction *cloneInstructionInExitBlock(
-    Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo *LI,
-    const LoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU);
-
-static void eraseInstruction(Instruction &I, ICFLoopSafetyInfo &SafetyInfo,
-                             AliasSetTracker *AST, MemorySSAUpdater *MSSAU);
-
-static void moveInstructionBefore(Instruction &I, Instruction &Dest,
-                                  ICFLoopSafetyInfo &SafetyInfo,
-                                  MemorySSAUpdater *MSSAU, ScalarEvolution *SE);
-
-namespace {
-struct LoopInvariantCodeMotion {
-  bool runOnLoop(Loop *L, AAResults *AA, LoopInfo *LI, DominatorTree *DT,
+static Instruction *cloneInstructionInExitBlock( 
+    Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo *LI, 
+    const LoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU); 
+ 
+static void eraseInstruction(Instruction &I, ICFLoopSafetyInfo &SafetyInfo, 
+                             AliasSetTracker *AST, MemorySSAUpdater *MSSAU); 
+ 
+static void moveInstructionBefore(Instruction &I, Instruction &Dest, 
+                                  ICFLoopSafetyInfo &SafetyInfo, 
+                                  MemorySSAUpdater *MSSAU, ScalarEvolution *SE); 
+ 
+namespace { 
+struct LoopInvariantCodeMotion { 
+  bool runOnLoop(Loop *L, AAResults *AA, LoopInfo *LI, DominatorTree *DT, 
                  BlockFrequencyInfo *BFI, TargetLibraryInfo *TLI,
                  TargetTransformInfo *TTI, ScalarEvolution *SE, MemorySSA *MSSA,
-                 OptimizationRemarkEmitter *ORE);
-
-  LoopInvariantCodeMotion(unsigned LicmMssaOptCap,
-                          unsigned LicmMssaNoAccForPromotionCap)
-      : LicmMssaOptCap(LicmMssaOptCap),
-        LicmMssaNoAccForPromotionCap(LicmMssaNoAccForPromotionCap) {}
-
-private:
-  unsigned LicmMssaOptCap;
-  unsigned LicmMssaNoAccForPromotionCap;
-
-  std::unique_ptr<AliasSetTracker>
-  collectAliasInfoForLoop(Loop *L, LoopInfo *LI, AAResults *AA);
-  std::unique_ptr<AliasSetTracker>
-  collectAliasInfoForLoopWithMSSA(Loop *L, AAResults *AA,
-                                  MemorySSAUpdater *MSSAU);
-};
-
-struct LegacyLICMPass : public LoopPass {
-  static char ID; // Pass identification, replacement for typeid
-  LegacyLICMPass(
-      unsigned LicmMssaOptCap = SetLicmMssaOptCap,
-      unsigned LicmMssaNoAccForPromotionCap = SetLicmMssaNoAccForPromotionCap)
-      : LoopPass(ID), LICM(LicmMssaOptCap, LicmMssaNoAccForPromotionCap) {
-    initializeLegacyLICMPassPass(*PassRegistry::getPassRegistry());
-  }
-
-  bool runOnLoop(Loop *L, LPPassManager &LPM) override {
-    if (skipLoop(L))
-      return false;
-
+                 OptimizationRemarkEmitter *ORE); 
+ 
+  LoopInvariantCodeMotion(unsigned LicmMssaOptCap, 
+                          unsigned LicmMssaNoAccForPromotionCap) 
+      : LicmMssaOptCap(LicmMssaOptCap), 
+        LicmMssaNoAccForPromotionCap(LicmMssaNoAccForPromotionCap) {} 
+ 
+private: 
+  unsigned LicmMssaOptCap; 
+  unsigned LicmMssaNoAccForPromotionCap; 
+ 
+  std::unique_ptr<AliasSetTracker> 
+  collectAliasInfoForLoop(Loop *L, LoopInfo *LI, AAResults *AA); 
+  std::unique_ptr<AliasSetTracker> 
+  collectAliasInfoForLoopWithMSSA(Loop *L, AAResults *AA, 
+                                  MemorySSAUpdater *MSSAU); 
+}; 
+ 
+struct LegacyLICMPass : public LoopPass { 
+  static char ID; // Pass identification, replacement for typeid 
+  LegacyLICMPass( 
+      unsigned LicmMssaOptCap = SetLicmMssaOptCap, 
+      unsigned LicmMssaNoAccForPromotionCap = SetLicmMssaNoAccForPromotionCap) 
+      : LoopPass(ID), LICM(LicmMssaOptCap, LicmMssaNoAccForPromotionCap) { 
+    initializeLegacyLICMPassPass(*PassRegistry::getPassRegistry()); 
+  } 
+ 
+  bool runOnLoop(Loop *L, LPPassManager &LPM) override { 
+    if (skipLoop(L)) 
+      return false; 
+ 
     LLVM_DEBUG(dbgs() << "Perform LICM on Loop with header at block "
                       << L->getHeader()->getNameOrAsOperand() << "\n");
 
-    auto *SE = getAnalysisIfAvailable<ScalarEvolutionWrapperPass>();
-    MemorySSA *MSSA = EnableMSSALoopDependency
-                          ? (&getAnalysis<MemorySSAWrapperPass>().getMSSA())
-                          : nullptr;
+    auto *SE = getAnalysisIfAvailable<ScalarEvolutionWrapperPass>(); 
+    MemorySSA *MSSA = EnableMSSALoopDependency 
+                          ? (&getAnalysis<MemorySSAWrapperPass>().getMSSA()) 
+                          : nullptr; 
     bool hasProfileData = L->getHeader()->getParent()->hasProfileData();
     BlockFrequencyInfo *BFI =
         hasProfileData ? &getAnalysis<LazyBlockFrequencyInfoPass>().getBFI()
                        : nullptr;
-    // For the old PM, we can't use OptimizationRemarkEmitter as an analysis
+    // For the old PM, we can't use OptimizationRemarkEmitter as an analysis 
     // pass. Function analyses need to be preserved across loop transformations
-    // but ORE cannot be preserved (see comment before the pass definition).
-    OptimizationRemarkEmitter ORE(L->getHeader()->getParent());
+    // but ORE cannot be preserved (see comment before the pass definition). 
+    OptimizationRemarkEmitter ORE(L->getHeader()->getParent()); 
     return LICM.runOnLoop(
         L, &getAnalysis<AAResultsWrapperPass>().getAAResults(),
         &getAnalysis<LoopInfoWrapperPass>().getLoopInfo(),
@@ -245,70 +245,70 @@ struct LegacyLICMPass : public LoopPass {
         &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(
             *L->getHeader()->getParent()),
         SE ? &SE->getSE() : nullptr, MSSA, &ORE);
-  }
-
-  /// This transformation requires natural loop information & requires that
-  /// loop preheaders be inserted into the CFG...
-  ///
-  void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.addPreserved<DominatorTreeWrapperPass>();
-    AU.addPreserved<LoopInfoWrapperPass>();
-    AU.addRequired<TargetLibraryInfoWrapperPass>();
-    if (EnableMSSALoopDependency) {
-      AU.addRequired<MemorySSAWrapperPass>();
-      AU.addPreserved<MemorySSAWrapperPass>();
-    }
-    AU.addRequired<TargetTransformInfoWrapperPass>();
-    getLoopAnalysisUsage(AU);
+  } 
+ 
+  /// This transformation requires natural loop information & requires that 
+  /// loop preheaders be inserted into the CFG... 
+  /// 
+  void getAnalysisUsage(AnalysisUsage &AU) const override { 
+    AU.addPreserved<DominatorTreeWrapperPass>(); 
+    AU.addPreserved<LoopInfoWrapperPass>(); 
+    AU.addRequired<TargetLibraryInfoWrapperPass>(); 
+    if (EnableMSSALoopDependency) { 
+      AU.addRequired<MemorySSAWrapperPass>(); 
+      AU.addPreserved<MemorySSAWrapperPass>(); 
+    } 
+    AU.addRequired<TargetTransformInfoWrapperPass>(); 
+    getLoopAnalysisUsage(AU); 
     LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AU);
     AU.addPreserved<LazyBlockFrequencyInfoPass>();
     AU.addPreserved<LazyBranchProbabilityInfoPass>();
-  }
-
-private:
-  LoopInvariantCodeMotion LICM;
-};
-} // namespace
-
-PreservedAnalyses LICMPass::run(Loop &L, LoopAnalysisManager &AM,
-                                LoopStandardAnalysisResults &AR, LPMUpdater &) {
-  // For the new PM, we also can't use OptimizationRemarkEmitter as an analysis
-  // pass.  Function analyses need to be preserved across loop transformations
-  // but ORE cannot be preserved (see comment before the pass definition).
-  OptimizationRemarkEmitter ORE(L.getHeader()->getParent());
-
-  LoopInvariantCodeMotion LICM(LicmMssaOptCap, LicmMssaNoAccForPromotionCap);
+  } 
+ 
+private: 
+  LoopInvariantCodeMotion LICM; 
+}; 
+} // namespace 
+ 
+PreservedAnalyses LICMPass::run(Loop &L, LoopAnalysisManager &AM, 
+                                LoopStandardAnalysisResults &AR, LPMUpdater &) { 
+  // For the new PM, we also can't use OptimizationRemarkEmitter as an analysis 
+  // pass.  Function analyses need to be preserved across loop transformations 
+  // but ORE cannot be preserved (see comment before the pass definition). 
+  OptimizationRemarkEmitter ORE(L.getHeader()->getParent()); 
+ 
+  LoopInvariantCodeMotion LICM(LicmMssaOptCap, LicmMssaNoAccForPromotionCap); 
   if (!LICM.runOnLoop(&L, &AR.AA, &AR.LI, &AR.DT, AR.BFI, &AR.TLI, &AR.TTI,
                       &AR.SE, AR.MSSA, &ORE))
-    return PreservedAnalyses::all();
-
-  auto PA = getLoopPassPreservedAnalyses();
-
-  PA.preserve<DominatorTreeAnalysis>();
-  PA.preserve<LoopAnalysis>();
-  if (AR.MSSA)
-    PA.preserve<MemorySSAAnalysis>();
-
-  return PA;
-}
-
-char LegacyLICMPass::ID = 0;
-INITIALIZE_PASS_BEGIN(LegacyLICMPass, "licm", "Loop Invariant Code Motion",
-                      false, false)
-INITIALIZE_PASS_DEPENDENCY(LoopPass)
-INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(MemorySSAWrapperPass)
+    return PreservedAnalyses::all(); 
+ 
+  auto PA = getLoopPassPreservedAnalyses(); 
+ 
+  PA.preserve<DominatorTreeAnalysis>(); 
+  PA.preserve<LoopAnalysis>(); 
+  if (AR.MSSA) 
+    PA.preserve<MemorySSAAnalysis>(); 
+ 
+  return PA; 
+} 
+ 
+char LegacyLICMPass::ID = 0; 
+INITIALIZE_PASS_BEGIN(LegacyLICMPass, "licm", "Loop Invariant Code Motion", 
+                      false, false) 
+INITIALIZE_PASS_DEPENDENCY(LoopPass) 
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) 
+INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass) 
+INITIALIZE_PASS_DEPENDENCY(MemorySSAWrapperPass) 
 INITIALIZE_PASS_DEPENDENCY(LazyBFIPass)
-INITIALIZE_PASS_END(LegacyLICMPass, "licm", "Loop Invariant Code Motion", false,
-                    false)
-
-Pass *llvm::createLICMPass() { return new LegacyLICMPass(); }
-Pass *llvm::createLICMPass(unsigned LicmMssaOptCap,
-                           unsigned LicmMssaNoAccForPromotionCap) {
-  return new LegacyLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap);
-}
-
+INITIALIZE_PASS_END(LegacyLICMPass, "licm", "Loop Invariant Code Motion", false, 
+                    false) 
+ 
+Pass *llvm::createLICMPass() { return new LegacyLICMPass(); } 
+Pass *llvm::createLICMPass(unsigned LicmMssaOptCap, 
+                           unsigned LicmMssaNoAccForPromotionCap) { 
+  return new LegacyLICMPass(LicmMssaOptCap, LicmMssaNoAccForPromotionCap); 
+} 
+ 
 llvm::SinkAndHoistLICMFlags::SinkAndHoistLICMFlags(bool IsSink, Loop *L,
                                                    MemorySSA *MSSA)
     : SinkAndHoistLICMFlags(SetLicmMssaOptCap, SetLicmMssaNoAccForPromotionCap,
@@ -338,456 +338,456 @@ llvm::SinkAndHoistLICMFlags::SinkAndHoistLICMFlags(
       }
 }
 
-/// Hoist expressions out of the specified loop. Note, alias info for inner
-/// loop is not preserved so it is not a good idea to run LICM multiple
-/// times on one loop.
-bool LoopInvariantCodeMotion::runOnLoop(
-    Loop *L, AAResults *AA, LoopInfo *LI, DominatorTree *DT,
+/// Hoist expressions out of the specified loop. Note, alias info for inner 
+/// loop is not preserved so it is not a good idea to run LICM multiple 
+/// times on one loop. 
+bool LoopInvariantCodeMotion::runOnLoop( 
+    Loop *L, AAResults *AA, LoopInfo *LI, DominatorTree *DT, 
     BlockFrequencyInfo *BFI, TargetLibraryInfo *TLI, TargetTransformInfo *TTI,
     ScalarEvolution *SE, MemorySSA *MSSA, OptimizationRemarkEmitter *ORE) {
-  bool Changed = false;
-
-  assert(L->isLCSSAForm(*DT) && "Loop is not in LCSSA form.");
-
-  // If this loop has metadata indicating that LICM is not to be performed then
-  // just exit.
-  if (hasDisableLICMTransformsHint(L)) {
-    return false;
-  }
-
-  std::unique_ptr<AliasSetTracker> CurAST;
-  std::unique_ptr<MemorySSAUpdater> MSSAU;
+  bool Changed = false; 
+ 
+  assert(L->isLCSSAForm(*DT) && "Loop is not in LCSSA form."); 
+ 
+  // If this loop has metadata indicating that LICM is not to be performed then 
+  // just exit. 
+  if (hasDisableLICMTransformsHint(L)) { 
+    return false; 
+  } 
+ 
+  std::unique_ptr<AliasSetTracker> CurAST; 
+  std::unique_ptr<MemorySSAUpdater> MSSAU; 
   std::unique_ptr<SinkAndHoistLICMFlags> Flags;
-
-  if (!MSSA) {
-    LLVM_DEBUG(dbgs() << "LICM: Using Alias Set Tracker.\n");
-    CurAST = collectAliasInfoForLoop(L, LI, AA);
+ 
+  if (!MSSA) { 
+    LLVM_DEBUG(dbgs() << "LICM: Using Alias Set Tracker.\n"); 
+    CurAST = collectAliasInfoForLoop(L, LI, AA); 
     Flags = std::make_unique<SinkAndHoistLICMFlags>(
         LicmMssaOptCap, LicmMssaNoAccForPromotionCap, /*IsSink=*/true);
-  } else {
-    LLVM_DEBUG(dbgs() << "LICM: Using MemorySSA.\n");
-    MSSAU = std::make_unique<MemorySSAUpdater>(MSSA);
+  } else { 
+    LLVM_DEBUG(dbgs() << "LICM: Using MemorySSA.\n"); 
+    MSSAU = std::make_unique<MemorySSAUpdater>(MSSA); 
     Flags = std::make_unique<SinkAndHoistLICMFlags>(
         LicmMssaOptCap, LicmMssaNoAccForPromotionCap, /*IsSink=*/true, L, MSSA);
-  }
-
-  // Get the preheader block to move instructions into...
-  BasicBlock *Preheader = L->getLoopPreheader();
-
-  // Compute loop safety information.
-  ICFLoopSafetyInfo SafetyInfo;
-  SafetyInfo.computeLoopSafetyInfo(L);
-
-  // We want to visit all of the instructions in this loop... that are not parts
-  // of our subloops (they have already had their invariants hoisted out of
-  // their loop, into this loop, so there is no need to process the BODIES of
-  // the subloops).
-  //
-  // Traverse the body of the loop in depth first order on the dominator tree so
-  // that we are guaranteed to see definitions before we see uses.  This allows
-  // us to sink instructions in one pass, without iteration.  After sinking
-  // instructions, we perform another pass to hoist them out of the loop.
-  if (L->hasDedicatedExits())
+  } 
+ 
+  // Get the preheader block to move instructions into... 
+  BasicBlock *Preheader = L->getLoopPreheader(); 
+ 
+  // Compute loop safety information. 
+  ICFLoopSafetyInfo SafetyInfo; 
+  SafetyInfo.computeLoopSafetyInfo(L); 
+ 
+  // We want to visit all of the instructions in this loop... that are not parts 
+  // of our subloops (they have already had their invariants hoisted out of 
+  // their loop, into this loop, so there is no need to process the BODIES of 
+  // the subloops). 
+  // 
+  // Traverse the body of the loop in depth first order on the dominator tree so 
+  // that we are guaranteed to see definitions before we see uses.  This allows 
+  // us to sink instructions in one pass, without iteration.  After sinking 
+  // instructions, we perform another pass to hoist them out of the loop. 
+  if (L->hasDedicatedExits()) 
     Changed |=
         sinkRegion(DT->getNode(L->getHeader()), AA, LI, DT, BFI, TLI, TTI, L,
                    CurAST.get(), MSSAU.get(), &SafetyInfo, *Flags.get(), ORE);
   Flags->setIsSink(false);
-  if (Preheader)
+  if (Preheader) 
     Changed |= hoistRegion(DT->getNode(L->getHeader()), AA, LI, DT, BFI, TLI, L,
                            CurAST.get(), MSSAU.get(), SE, &SafetyInfo,
                            *Flags.get(), ORE);
-
-  // Now that all loop invariants have been removed from the loop, promote any
-  // memory references to scalars that we can.
-  // Don't sink stores from loops without dedicated block exits. Exits
-  // containing indirect branches are not transformed by loop simplify,
-  // make sure we catch that. An additional load may be generated in the
-  // preheader for SSA updater, so also avoid sinking when no preheader
-  // is available.
-  if (!DisablePromotion && Preheader && L->hasDedicatedExits() &&
+ 
+  // Now that all loop invariants have been removed from the loop, promote any 
+  // memory references to scalars that we can. 
+  // Don't sink stores from loops without dedicated block exits. Exits 
+  // containing indirect branches are not transformed by loop simplify, 
+  // make sure we catch that. An additional load may be generated in the 
+  // preheader for SSA updater, so also avoid sinking when no preheader 
+  // is available. 
+  if (!DisablePromotion && Preheader && L->hasDedicatedExits() && 
       !Flags->tooManyMemoryAccesses()) {
-    // Figure out the loop exits and their insertion points
-    SmallVector<BasicBlock *, 8> ExitBlocks;
-    L->getUniqueExitBlocks(ExitBlocks);
-
-    // We can't insert into a catchswitch.
-    bool HasCatchSwitch = llvm::any_of(ExitBlocks, [](BasicBlock *Exit) {
-      return isa<CatchSwitchInst>(Exit->getTerminator());
-    });
-
-    if (!HasCatchSwitch) {
-      SmallVector<Instruction *, 8> InsertPts;
-      SmallVector<MemoryAccess *, 8> MSSAInsertPts;
-      InsertPts.reserve(ExitBlocks.size());
-      if (MSSAU)
-        MSSAInsertPts.reserve(ExitBlocks.size());
-      for (BasicBlock *ExitBlock : ExitBlocks) {
-        InsertPts.push_back(&*ExitBlock->getFirstInsertionPt());
-        if (MSSAU)
-          MSSAInsertPts.push_back(nullptr);
-      }
-
-      PredIteratorCache PIC;
-
-      bool Promoted = false;
-
-      // Build an AST using MSSA.
-      if (!CurAST.get())
-        CurAST = collectAliasInfoForLoopWithMSSA(L, AA, MSSAU.get());
-
-      // Loop over all of the alias sets in the tracker object.
-      for (AliasSet &AS : *CurAST) {
-        // We can promote this alias set if it has a store, if it is a "Must"
-        // alias set, if the pointer is loop invariant, and if we are not
-        // eliminating any volatile loads or stores.
-        if (AS.isForwardingAliasSet() || !AS.isMod() || !AS.isMustAlias() ||
-            !L->isLoopInvariant(AS.begin()->getValue()))
-          continue;
-
-        assert(
-            !AS.empty() &&
-            "Must alias set should have at least one pointer element in it!");
-
-        SmallSetVector<Value *, 8> PointerMustAliases;
-        for (const auto &ASI : AS)
-          PointerMustAliases.insert(ASI.getValue());
-
-        Promoted |= promoteLoopAccessesToScalars(
-            PointerMustAliases, ExitBlocks, InsertPts, MSSAInsertPts, PIC, LI,
-            DT, TLI, L, CurAST.get(), MSSAU.get(), &SafetyInfo, ORE);
-      }
-
-      // Once we have promoted values across the loop body we have to
-      // recursively reform LCSSA as any nested loop may now have values defined
-      // within the loop used in the outer loop.
-      // FIXME: This is really heavy handed. It would be a bit better to use an
-      // SSAUpdater strategy during promotion that was LCSSA aware and reformed
-      // it as it went.
-      if (Promoted)
-        formLCSSARecursively(*L, *DT, LI, SE);
-
-      Changed |= Promoted;
-    }
-  }
-
-  // Check that neither this loop nor its parent have had LCSSA broken. LICM is
-  // specifically moving instructions across the loop boundary and so it is
-  // especially in need of sanity checking here.
-  assert(L->isLCSSAForm(*DT) && "Loop not left in LCSSA form after LICM!");
+    // Figure out the loop exits and their insertion points 
+    SmallVector<BasicBlock *, 8> ExitBlocks; 
+    L->getUniqueExitBlocks(ExitBlocks); 
+ 
+    // We can't insert into a catchswitch. 
+    bool HasCatchSwitch = llvm::any_of(ExitBlocks, [](BasicBlock *Exit) { 
+      return isa<CatchSwitchInst>(Exit->getTerminator()); 
+    }); 
+ 
+    if (!HasCatchSwitch) { 
+      SmallVector<Instruction *, 8> InsertPts; 
+      SmallVector<MemoryAccess *, 8> MSSAInsertPts; 
+      InsertPts.reserve(ExitBlocks.size()); 
+      if (MSSAU) 
+        MSSAInsertPts.reserve(ExitBlocks.size()); 
+      for (BasicBlock *ExitBlock : ExitBlocks) { 
+        InsertPts.push_back(&*ExitBlock->getFirstInsertionPt()); 
+        if (MSSAU) 
+          MSSAInsertPts.push_back(nullptr); 
+      } 
+ 
+      PredIteratorCache PIC; 
+ 
+      bool Promoted = false; 
+ 
+      // Build an AST using MSSA. 
+      if (!CurAST.get()) 
+        CurAST = collectAliasInfoForLoopWithMSSA(L, AA, MSSAU.get()); 
+ 
+      // Loop over all of the alias sets in the tracker object. 
+      for (AliasSet &AS : *CurAST) { 
+        // We can promote this alias set if it has a store, if it is a "Must" 
+        // alias set, if the pointer is loop invariant, and if we are not 
+        // eliminating any volatile loads or stores. 
+        if (AS.isForwardingAliasSet() || !AS.isMod() || !AS.isMustAlias() || 
+            !L->isLoopInvariant(AS.begin()->getValue())) 
+          continue; 
+ 
+        assert( 
+            !AS.empty() && 
+            "Must alias set should have at least one pointer element in it!"); 
+ 
+        SmallSetVector<Value *, 8> PointerMustAliases; 
+        for (const auto &ASI : AS) 
+          PointerMustAliases.insert(ASI.getValue()); 
+ 
+        Promoted |= promoteLoopAccessesToScalars( 
+            PointerMustAliases, ExitBlocks, InsertPts, MSSAInsertPts, PIC, LI, 
+            DT, TLI, L, CurAST.get(), MSSAU.get(), &SafetyInfo, ORE); 
+      } 
+ 
+      // Once we have promoted values across the loop body we have to 
+      // recursively reform LCSSA as any nested loop may now have values defined 
+      // within the loop used in the outer loop. 
+      // FIXME: This is really heavy handed. It would be a bit better to use an 
+      // SSAUpdater strategy during promotion that was LCSSA aware and reformed 
+      // it as it went. 
+      if (Promoted) 
+        formLCSSARecursively(*L, *DT, LI, SE); 
+ 
+      Changed |= Promoted; 
+    } 
+  } 
+ 
+  // Check that neither this loop nor its parent have had LCSSA broken. LICM is 
+  // specifically moving instructions across the loop boundary and so it is 
+  // especially in need of sanity checking here. 
+  assert(L->isLCSSAForm(*DT) && "Loop not left in LCSSA form after LICM!"); 
   assert((L->isOutermost() || L->getParentLoop()->isLCSSAForm(*DT)) &&
-         "Parent loop not left in LCSSA form after LICM!");
-
-  if (MSSAU.get() && VerifyMemorySSA)
-    MSSAU->getMemorySSA()->verifyMemorySSA();
-
-  if (Changed && SE)
-    SE->forgetLoopDispositions(L);
-  return Changed;
-}
-
-/// Walk the specified region of the CFG (defined by all blocks dominated by
-/// the specified block, and that are in the current loop) in reverse depth
-/// first order w.r.t the DominatorTree.  This allows us to visit uses before
-/// definitions, allowing us to sink a loop body in one pass without iteration.
-///
-bool llvm::sinkRegion(DomTreeNode *N, AAResults *AA, LoopInfo *LI,
+         "Parent loop not left in LCSSA form after LICM!"); 
+ 
+  if (MSSAU.get() && VerifyMemorySSA) 
+    MSSAU->getMemorySSA()->verifyMemorySSA(); 
+ 
+  if (Changed && SE) 
+    SE->forgetLoopDispositions(L); 
+  return Changed; 
+} 
+ 
+/// Walk the specified region of the CFG (defined by all blocks dominated by 
+/// the specified block, and that are in the current loop) in reverse depth 
+/// first order w.r.t the DominatorTree.  This allows us to visit uses before 
+/// definitions, allowing us to sink a loop body in one pass without iteration. 
+/// 
+bool llvm::sinkRegion(DomTreeNode *N, AAResults *AA, LoopInfo *LI, 
                       DominatorTree *DT, BlockFrequencyInfo *BFI,
                       TargetLibraryInfo *TLI, TargetTransformInfo *TTI,
                       Loop *CurLoop, AliasSetTracker *CurAST,
                       MemorySSAUpdater *MSSAU, ICFLoopSafetyInfo *SafetyInfo,
-                      SinkAndHoistLICMFlags &Flags,
-                      OptimizationRemarkEmitter *ORE) {
-
-  // Verify inputs.
-  assert(N != nullptr && AA != nullptr && LI != nullptr && DT != nullptr &&
-         CurLoop != nullptr && SafetyInfo != nullptr &&
-         "Unexpected input to sinkRegion.");
-  assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) &&
-         "Either AliasSetTracker or MemorySSA should be initialized.");
-
-  // We want to visit children before parents. We will enque all the parents
-  // before their children in the worklist and process the worklist in reverse
-  // order.
-  SmallVector<DomTreeNode *, 16> Worklist = collectChildrenInLoop(N, CurLoop);
-
-  bool Changed = false;
-  for (DomTreeNode *DTN : reverse(Worklist)) {
-    BasicBlock *BB = DTN->getBlock();
-    // Only need to process the contents of this block if it is not part of a
-    // subloop (which would already have been processed).
-    if (inSubLoop(BB, CurLoop, LI))
-      continue;
-
-    for (BasicBlock::iterator II = BB->end(); II != BB->begin();) {
-      Instruction &I = *--II;
-
-      // If the instruction is dead, we would try to sink it because it isn't
-      // used in the loop, instead, just delete it.
-      if (isInstructionTriviallyDead(&I, TLI)) {
-        LLVM_DEBUG(dbgs() << "LICM deleting dead inst: " << I << '\n');
-        salvageKnowledge(&I);
-        salvageDebugInfo(I);
-        ++II;
-        eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
-        Changed = true;
-        continue;
-      }
-
-      // Check to see if we can sink this instruction to the exit blocks
-      // of the loop.  We can do this if the all users of the instruction are
-      // outside of the loop.  In this case, it doesn't even matter if the
-      // operands of the instruction are loop invariant.
-      //
-      bool FreeInLoop = false;
-      if (!I.mayHaveSideEffects() &&
-          isNotUsedOrFreeInLoop(I, CurLoop, SafetyInfo, TTI, FreeInLoop) &&
-          canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, MSSAU, true, &Flags,
-                             ORE)) {
+                      SinkAndHoistLICMFlags &Flags, 
+                      OptimizationRemarkEmitter *ORE) { 
+ 
+  // Verify inputs. 
+  assert(N != nullptr && AA != nullptr && LI != nullptr && DT != nullptr && 
+         CurLoop != nullptr && SafetyInfo != nullptr && 
+         "Unexpected input to sinkRegion."); 
+  assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) && 
+         "Either AliasSetTracker or MemorySSA should be initialized."); 
+ 
+  // We want to visit children before parents. We will enque all the parents 
+  // before their children in the worklist and process the worklist in reverse 
+  // order. 
+  SmallVector<DomTreeNode *, 16> Worklist = collectChildrenInLoop(N, CurLoop); 
+ 
+  bool Changed = false; 
+  for (DomTreeNode *DTN : reverse(Worklist)) { 
+    BasicBlock *BB = DTN->getBlock(); 
+    // Only need to process the contents of this block if it is not part of a 
+    // subloop (which would already have been processed). 
+    if (inSubLoop(BB, CurLoop, LI)) 
+      continue; 
+ 
+    for (BasicBlock::iterator II = BB->end(); II != BB->begin();) { 
+      Instruction &I = *--II; 
+ 
+      // If the instruction is dead, we would try to sink it because it isn't 
+      // used in the loop, instead, just delete it. 
+      if (isInstructionTriviallyDead(&I, TLI)) { 
+        LLVM_DEBUG(dbgs() << "LICM deleting dead inst: " << I << '\n'); 
+        salvageKnowledge(&I); 
+        salvageDebugInfo(I); 
+        ++II; 
+        eraseInstruction(I, *SafetyInfo, CurAST, MSSAU); 
+        Changed = true; 
+        continue; 
+      } 
+ 
+      // Check to see if we can sink this instruction to the exit blocks 
+      // of the loop.  We can do this if the all users of the instruction are 
+      // outside of the loop.  In this case, it doesn't even matter if the 
+      // operands of the instruction are loop invariant. 
+      // 
+      bool FreeInLoop = false; 
+      if (!I.mayHaveSideEffects() && 
+          isNotUsedOrFreeInLoop(I, CurLoop, SafetyInfo, TTI, FreeInLoop) && 
+          canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, MSSAU, true, &Flags, 
+                             ORE)) { 
         if (sink(I, LI, DT, BFI, CurLoop, SafetyInfo, MSSAU, ORE)) {
-          if (!FreeInLoop) {
-            ++II;
-            salvageDebugInfo(I);
-            eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
-          }
-          Changed = true;
-        }
-      }
-    }
-  }
-  if (MSSAU && VerifyMemorySSA)
-    MSSAU->getMemorySSA()->verifyMemorySSA();
-  return Changed;
-}
-
-namespace {
-// This is a helper class for hoistRegion to make it able to hoist control flow
-// in order to be able to hoist phis. The way this works is that we initially
-// start hoisting to the loop preheader, and when we see a loop invariant branch
-// we make note of this. When we then come to hoist an instruction that's
-// conditional on such a branch we duplicate the branch and the relevant control
-// flow, then hoist the instruction into the block corresponding to its original
-// block in the duplicated control flow.
-class ControlFlowHoister {
-private:
-  // Information about the loop we are hoisting from
-  LoopInfo *LI;
-  DominatorTree *DT;
-  Loop *CurLoop;
-  MemorySSAUpdater *MSSAU;
-
-  // A map of blocks in the loop to the block their instructions will be hoisted
-  // to.
-  DenseMap<BasicBlock *, BasicBlock *> HoistDestinationMap;
-
-  // The branches that we can hoist, mapped to the block that marks a
-  // convergence point of their control flow.
-  DenseMap<BranchInst *, BasicBlock *> HoistableBranches;
-
-public:
-  ControlFlowHoister(LoopInfo *LI, DominatorTree *DT, Loop *CurLoop,
-                     MemorySSAUpdater *MSSAU)
-      : LI(LI), DT(DT), CurLoop(CurLoop), MSSAU(MSSAU) {}
-
-  void registerPossiblyHoistableBranch(BranchInst *BI) {
-    // We can only hoist conditional branches with loop invariant operands.
-    if (!ControlFlowHoisting || !BI->isConditional() ||
-        !CurLoop->hasLoopInvariantOperands(BI))
-      return;
-
-    // The branch destinations need to be in the loop, and we don't gain
-    // anything by duplicating conditional branches with duplicate successors,
-    // as it's essentially the same as an unconditional branch.
-    BasicBlock *TrueDest = BI->getSuccessor(0);
-    BasicBlock *FalseDest = BI->getSuccessor(1);
-    if (!CurLoop->contains(TrueDest) || !CurLoop->contains(FalseDest) ||
-        TrueDest == FalseDest)
-      return;
-
-    // We can hoist BI if one branch destination is the successor of the other,
-    // or both have common successor which we check by seeing if the
-    // intersection of their successors is non-empty.
-    // TODO: This could be expanded to allowing branches where both ends
-    // eventually converge to a single block.
-    SmallPtrSet<BasicBlock *, 4> TrueDestSucc, FalseDestSucc;
-    TrueDestSucc.insert(succ_begin(TrueDest), succ_end(TrueDest));
-    FalseDestSucc.insert(succ_begin(FalseDest), succ_end(FalseDest));
-    BasicBlock *CommonSucc = nullptr;
-    if (TrueDestSucc.count(FalseDest)) {
-      CommonSucc = FalseDest;
-    } else if (FalseDestSucc.count(TrueDest)) {
-      CommonSucc = TrueDest;
-    } else {
-      set_intersect(TrueDestSucc, FalseDestSucc);
-      // If there's one common successor use that.
-      if (TrueDestSucc.size() == 1)
-        CommonSucc = *TrueDestSucc.begin();
-      // If there's more than one pick whichever appears first in the block list
-      // (we can't use the value returned by TrueDestSucc.begin() as it's
-      // unpredicatable which element gets returned).
-      else if (!TrueDestSucc.empty()) {
-        Function *F = TrueDest->getParent();
-        auto IsSucc = [&](BasicBlock &BB) { return TrueDestSucc.count(&BB); };
+          if (!FreeInLoop) { 
+            ++II; 
+            salvageDebugInfo(I); 
+            eraseInstruction(I, *SafetyInfo, CurAST, MSSAU); 
+          } 
+          Changed = true; 
+        } 
+      } 
+    } 
+  } 
+  if (MSSAU && VerifyMemorySSA) 
+    MSSAU->getMemorySSA()->verifyMemorySSA(); 
+  return Changed; 
+} 
+ 
+namespace { 
+// This is a helper class for hoistRegion to make it able to hoist control flow 
+// in order to be able to hoist phis. The way this works is that we initially 
+// start hoisting to the loop preheader, and when we see a loop invariant branch 
+// we make note of this. When we then come to hoist an instruction that's 
+// conditional on such a branch we duplicate the branch and the relevant control 
+// flow, then hoist the instruction into the block corresponding to its original 
+// block in the duplicated control flow. 
+class ControlFlowHoister { 
+private: 
+  // Information about the loop we are hoisting from 
+  LoopInfo *LI; 
+  DominatorTree *DT; 
+  Loop *CurLoop; 
+  MemorySSAUpdater *MSSAU; 
+ 
+  // A map of blocks in the loop to the block their instructions will be hoisted 
+  // to. 
+  DenseMap<BasicBlock *, BasicBlock *> HoistDestinationMap; 
+ 
+  // The branches that we can hoist, mapped to the block that marks a 
+  // convergence point of their control flow. 
+  DenseMap<BranchInst *, BasicBlock *> HoistableBranches; 
+ 
+public: 
+  ControlFlowHoister(LoopInfo *LI, DominatorTree *DT, Loop *CurLoop, 
+                     MemorySSAUpdater *MSSAU) 
+      : LI(LI), DT(DT), CurLoop(CurLoop), MSSAU(MSSAU) {} 
+ 
+  void registerPossiblyHoistableBranch(BranchInst *BI) { 
+    // We can only hoist conditional branches with loop invariant operands. 
+    if (!ControlFlowHoisting || !BI->isConditional() || 
+        !CurLoop->hasLoopInvariantOperands(BI)) 
+      return; 
+ 
+    // The branch destinations need to be in the loop, and we don't gain 
+    // anything by duplicating conditional branches with duplicate successors, 
+    // as it's essentially the same as an unconditional branch. 
+    BasicBlock *TrueDest = BI->getSuccessor(0); 
+    BasicBlock *FalseDest = BI->getSuccessor(1); 
+    if (!CurLoop->contains(TrueDest) || !CurLoop->contains(FalseDest) || 
+        TrueDest == FalseDest) 
+      return; 
+ 
+    // We can hoist BI if one branch destination is the successor of the other, 
+    // or both have common successor which we check by seeing if the 
+    // intersection of their successors is non-empty. 
+    // TODO: This could be expanded to allowing branches where both ends 
+    // eventually converge to a single block. 
+    SmallPtrSet<BasicBlock *, 4> TrueDestSucc, FalseDestSucc; 
+    TrueDestSucc.insert(succ_begin(TrueDest), succ_end(TrueDest)); 
+    FalseDestSucc.insert(succ_begin(FalseDest), succ_end(FalseDest)); 
+    BasicBlock *CommonSucc = nullptr; 
+    if (TrueDestSucc.count(FalseDest)) { 
+      CommonSucc = FalseDest; 
+    } else if (FalseDestSucc.count(TrueDest)) { 
+      CommonSucc = TrueDest; 
+    } else { 
+      set_intersect(TrueDestSucc, FalseDestSucc); 
+      // If there's one common successor use that. 
+      if (TrueDestSucc.size() == 1) 
+        CommonSucc = *TrueDestSucc.begin(); 
+      // If there's more than one pick whichever appears first in the block list 
+      // (we can't use the value returned by TrueDestSucc.begin() as it's 
+      // unpredicatable which element gets returned). 
+      else if (!TrueDestSucc.empty()) { 
+        Function *F = TrueDest->getParent(); 
+        auto IsSucc = [&](BasicBlock &BB) { return TrueDestSucc.count(&BB); }; 
         auto It = llvm::find_if(*F, IsSucc);
-        assert(It != F->end() && "Could not find successor in function");
-        CommonSucc = &*It;
-      }
-    }
-    // The common successor has to be dominated by the branch, as otherwise
-    // there will be some other path to the successor that will not be
-    // controlled by this branch so any phi we hoist would be controlled by the
-    // wrong condition. This also takes care of avoiding hoisting of loop back
-    // edges.
-    // TODO: In some cases this could be relaxed if the successor is dominated
-    // by another block that's been hoisted and we can guarantee that the
-    // control flow has been replicated exactly.
-    if (CommonSucc && DT->dominates(BI, CommonSucc))
-      HoistableBranches[BI] = CommonSucc;
-  }
-
-  bool canHoistPHI(PHINode *PN) {
-    // The phi must have loop invariant operands.
-    if (!ControlFlowHoisting || !CurLoop->hasLoopInvariantOperands(PN))
-      return false;
-    // We can hoist phis if the block they are in is the target of hoistable
-    // branches which cover all of the predecessors of the block.
-    SmallPtrSet<BasicBlock *, 8> PredecessorBlocks;
-    BasicBlock *BB = PN->getParent();
-    for (BasicBlock *PredBB : predecessors(BB))
-      PredecessorBlocks.insert(PredBB);
-    // If we have less predecessor blocks than predecessors then the phi will
-    // have more than one incoming value for the same block which we can't
-    // handle.
-    // TODO: This could be handled be erasing some of the duplicate incoming
-    // values.
-    if (PredecessorBlocks.size() != pred_size(BB))
-      return false;
-    for (auto &Pair : HoistableBranches) {
-      if (Pair.second == BB) {
-        // Which blocks are predecessors via this branch depends on if the
-        // branch is triangle-like or diamond-like.
-        if (Pair.first->getSuccessor(0) == BB) {
-          PredecessorBlocks.erase(Pair.first->getParent());
-          PredecessorBlocks.erase(Pair.first->getSuccessor(1));
-        } else if (Pair.first->getSuccessor(1) == BB) {
-          PredecessorBlocks.erase(Pair.first->getParent());
-          PredecessorBlocks.erase(Pair.first->getSuccessor(0));
-        } else {
-          PredecessorBlocks.erase(Pair.first->getSuccessor(0));
-          PredecessorBlocks.erase(Pair.first->getSuccessor(1));
-        }
-      }
-    }
-    // PredecessorBlocks will now be empty if for every predecessor of BB we
-    // found a hoistable branch source.
-    return PredecessorBlocks.empty();
-  }
-
-  BasicBlock *getOrCreateHoistedBlock(BasicBlock *BB) {
-    if (!ControlFlowHoisting)
-      return CurLoop->getLoopPreheader();
-    // If BB has already been hoisted, return that
-    if (HoistDestinationMap.count(BB))
-      return HoistDestinationMap[BB];
-
-    // Check if this block is conditional based on a pending branch
-    auto HasBBAsSuccessor =
-        [&](DenseMap<BranchInst *, BasicBlock *>::value_type &Pair) {
-          return BB != Pair.second && (Pair.first->getSuccessor(0) == BB ||
-                                       Pair.first->getSuccessor(1) == BB);
-        };
+        assert(It != F->end() && "Could not find successor in function"); 
+        CommonSucc = &*It; 
+      } 
+    } 
+    // The common successor has to be dominated by the branch, as otherwise 
+    // there will be some other path to the successor that will not be 
+    // controlled by this branch so any phi we hoist would be controlled by the 
+    // wrong condition. This also takes care of avoiding hoisting of loop back 
+    // edges. 
+    // TODO: In some cases this could be relaxed if the successor is dominated 
+    // by another block that's been hoisted and we can guarantee that the 
+    // control flow has been replicated exactly. 
+    if (CommonSucc && DT->dominates(BI, CommonSucc)) 
+      HoistableBranches[BI] = CommonSucc; 
+  } 
+ 
+  bool canHoistPHI(PHINode *PN) { 
+    // The phi must have loop invariant operands. 
+    if (!ControlFlowHoisting || !CurLoop->hasLoopInvariantOperands(PN)) 
+      return false; 
+    // We can hoist phis if the block they are in is the target of hoistable 
+    // branches which cover all of the predecessors of the block. 
+    SmallPtrSet<BasicBlock *, 8> PredecessorBlocks; 
+    BasicBlock *BB = PN->getParent(); 
+    for (BasicBlock *PredBB : predecessors(BB)) 
+      PredecessorBlocks.insert(PredBB); 
+    // If we have less predecessor blocks than predecessors then the phi will 
+    // have more than one incoming value for the same block which we can't 
+    // handle. 
+    // TODO: This could be handled be erasing some of the duplicate incoming 
+    // values. 
+    if (PredecessorBlocks.size() != pred_size(BB)) 
+      return false; 
+    for (auto &Pair : HoistableBranches) { 
+      if (Pair.second == BB) { 
+        // Which blocks are predecessors via this branch depends on if the 
+        // branch is triangle-like or diamond-like. 
+        if (Pair.first->getSuccessor(0) == BB) { 
+          PredecessorBlocks.erase(Pair.first->getParent()); 
+          PredecessorBlocks.erase(Pair.first->getSuccessor(1)); 
+        } else if (Pair.first->getSuccessor(1) == BB) { 
+          PredecessorBlocks.erase(Pair.first->getParent()); 
+          PredecessorBlocks.erase(Pair.first->getSuccessor(0)); 
+        } else { 
+          PredecessorBlocks.erase(Pair.first->getSuccessor(0)); 
+          PredecessorBlocks.erase(Pair.first->getSuccessor(1)); 
+        } 
+      } 
+    } 
+    // PredecessorBlocks will now be empty if for every predecessor of BB we 
+    // found a hoistable branch source. 
+    return PredecessorBlocks.empty(); 
+  } 
+ 
+  BasicBlock *getOrCreateHoistedBlock(BasicBlock *BB) { 
+    if (!ControlFlowHoisting) 
+      return CurLoop->getLoopPreheader(); 
+    // If BB has already been hoisted, return that 
+    if (HoistDestinationMap.count(BB)) 
+      return HoistDestinationMap[BB]; 
+ 
+    // Check if this block is conditional based on a pending branch 
+    auto HasBBAsSuccessor = 
+        [&](DenseMap<BranchInst *, BasicBlock *>::value_type &Pair) { 
+          return BB != Pair.second && (Pair.first->getSuccessor(0) == BB || 
+                                       Pair.first->getSuccessor(1) == BB); 
+        }; 
     auto It = llvm::find_if(HoistableBranches, HasBBAsSuccessor);
-
-    // If not involved in a pending branch, hoist to preheader
-    BasicBlock *InitialPreheader = CurLoop->getLoopPreheader();
-    if (It == HoistableBranches.end()) {
+ 
+    // If not involved in a pending branch, hoist to preheader 
+    BasicBlock *InitialPreheader = CurLoop->getLoopPreheader(); 
+    if (It == HoistableBranches.end()) { 
       LLVM_DEBUG(dbgs() << "LICM using "
                         << InitialPreheader->getNameOrAsOperand()
                         << " as hoist destination for "
                         << BB->getNameOrAsOperand() << "\n");
-      HoistDestinationMap[BB] = InitialPreheader;
-      return InitialPreheader;
-    }
-    BranchInst *BI = It->first;
-    assert(std::find_if(++It, HoistableBranches.end(), HasBBAsSuccessor) ==
-               HoistableBranches.end() &&
-           "BB is expected to be the target of at most one branch");
-
-    LLVMContext &C = BB->getContext();
-    BasicBlock *TrueDest = BI->getSuccessor(0);
-    BasicBlock *FalseDest = BI->getSuccessor(1);
-    BasicBlock *CommonSucc = HoistableBranches[BI];
-    BasicBlock *HoistTarget = getOrCreateHoistedBlock(BI->getParent());
-
-    // Create hoisted versions of blocks that currently don't have them
-    auto CreateHoistedBlock = [&](BasicBlock *Orig) {
-      if (HoistDestinationMap.count(Orig))
-        return HoistDestinationMap[Orig];
-      BasicBlock *New =
-          BasicBlock::Create(C, Orig->getName() + ".licm", Orig->getParent());
-      HoistDestinationMap[Orig] = New;
-      DT->addNewBlock(New, HoistTarget);
-      if (CurLoop->getParentLoop())
-        CurLoop->getParentLoop()->addBasicBlockToLoop(New, *LI);
-      ++NumCreatedBlocks;
-      LLVM_DEBUG(dbgs() << "LICM created " << New->getName()
-                        << " as hoist destination for " << Orig->getName()
-                        << "\n");
-      return New;
-    };
-    BasicBlock *HoistTrueDest = CreateHoistedBlock(TrueDest);
-    BasicBlock *HoistFalseDest = CreateHoistedBlock(FalseDest);
-    BasicBlock *HoistCommonSucc = CreateHoistedBlock(CommonSucc);
-
-    // Link up these blocks with branches.
-    if (!HoistCommonSucc->getTerminator()) {
-      // The new common successor we've generated will branch to whatever that
-      // hoist target branched to.
-      BasicBlock *TargetSucc = HoistTarget->getSingleSuccessor();
-      assert(TargetSucc && "Expected hoist target to have a single successor");
-      HoistCommonSucc->moveBefore(TargetSucc);
-      BranchInst::Create(TargetSucc, HoistCommonSucc);
-    }
-    if (!HoistTrueDest->getTerminator()) {
-      HoistTrueDest->moveBefore(HoistCommonSucc);
-      BranchInst::Create(HoistCommonSucc, HoistTrueDest);
-    }
-    if (!HoistFalseDest->getTerminator()) {
-      HoistFalseDest->moveBefore(HoistCommonSucc);
-      BranchInst::Create(HoistCommonSucc, HoistFalseDest);
-    }
-
-    // If BI is being cloned to what was originally the preheader then
-    // HoistCommonSucc will now be the new preheader.
-    if (HoistTarget == InitialPreheader) {
-      // Phis in the loop header now need to use the new preheader.
-      InitialPreheader->replaceSuccessorsPhiUsesWith(HoistCommonSucc);
-      if (MSSAU)
-        MSSAU->wireOldPredecessorsToNewImmediatePredecessor(
-            HoistTarget->getSingleSuccessor(), HoistCommonSucc, {HoistTarget});
-      // The new preheader dominates the loop header.
-      DomTreeNode *PreheaderNode = DT->getNode(HoistCommonSucc);
-      DomTreeNode *HeaderNode = DT->getNode(CurLoop->getHeader());
-      DT->changeImmediateDominator(HeaderNode, PreheaderNode);
-      // The preheader hoist destination is now the new preheader, with the
-      // exception of the hoist destination of this branch.
-      for (auto &Pair : HoistDestinationMap)
-        if (Pair.second == InitialPreheader && Pair.first != BI->getParent())
-          Pair.second = HoistCommonSucc;
-    }
-
-    // Now finally clone BI.
-    ReplaceInstWithInst(
-        HoistTarget->getTerminator(),
-        BranchInst::Create(HoistTrueDest, HoistFalseDest, BI->getCondition()));
-    ++NumClonedBranches;
-
-    assert(CurLoop->getLoopPreheader() &&
-           "Hoisting blocks should not have destroyed preheader");
-    return HoistDestinationMap[BB];
-  }
-};
-} // namespace
-
+      HoistDestinationMap[BB] = InitialPreheader; 
+      return InitialPreheader; 
+    } 
+    BranchInst *BI = It->first; 
+    assert(std::find_if(++It, HoistableBranches.end(), HasBBAsSuccessor) == 
+               HoistableBranches.end() && 
+           "BB is expected to be the target of at most one branch"); 
+ 
+    LLVMContext &C = BB->getContext(); 
+    BasicBlock *TrueDest = BI->getSuccessor(0); 
+    BasicBlock *FalseDest = BI->getSuccessor(1); 
+    BasicBlock *CommonSucc = HoistableBranches[BI]; 
+    BasicBlock *HoistTarget = getOrCreateHoistedBlock(BI->getParent()); 
+ 
+    // Create hoisted versions of blocks that currently don't have them 
+    auto CreateHoistedBlock = [&](BasicBlock *Orig) { 
+      if (HoistDestinationMap.count(Orig)) 
+        return HoistDestinationMap[Orig]; 
+      BasicBlock *New = 
+          BasicBlock::Create(C, Orig->getName() + ".licm", Orig->getParent()); 
+      HoistDestinationMap[Orig] = New; 
+      DT->addNewBlock(New, HoistTarget); 
+      if (CurLoop->getParentLoop()) 
+        CurLoop->getParentLoop()->addBasicBlockToLoop(New, *LI); 
+      ++NumCreatedBlocks; 
+      LLVM_DEBUG(dbgs() << "LICM created " << New->getName() 
+                        << " as hoist destination for " << Orig->getName() 
+                        << "\n"); 
+      return New; 
+    }; 
+    BasicBlock *HoistTrueDest = CreateHoistedBlock(TrueDest); 
+    BasicBlock *HoistFalseDest = CreateHoistedBlock(FalseDest); 
+    BasicBlock *HoistCommonSucc = CreateHoistedBlock(CommonSucc); 
+ 
+    // Link up these blocks with branches. 
+    if (!HoistCommonSucc->getTerminator()) { 
+      // The new common successor we've generated will branch to whatever that 
+      // hoist target branched to. 
+      BasicBlock *TargetSucc = HoistTarget->getSingleSuccessor(); 
+      assert(TargetSucc && "Expected hoist target to have a single successor"); 
+      HoistCommonSucc->moveBefore(TargetSucc); 
+      BranchInst::Create(TargetSucc, HoistCommonSucc); 
+    } 
+    if (!HoistTrueDest->getTerminator()) { 
+      HoistTrueDest->moveBefore(HoistCommonSucc); 
+      BranchInst::Create(HoistCommonSucc, HoistTrueDest); 
+    } 
+    if (!HoistFalseDest->getTerminator()) { 
+      HoistFalseDest->moveBefore(HoistCommonSucc); 
+      BranchInst::Create(HoistCommonSucc, HoistFalseDest); 
+    } 
+ 
+    // If BI is being cloned to what was originally the preheader then 
+    // HoistCommonSucc will now be the new preheader. 
+    if (HoistTarget == InitialPreheader) { 
+      // Phis in the loop header now need to use the new preheader. 
+      InitialPreheader->replaceSuccessorsPhiUsesWith(HoistCommonSucc); 
+      if (MSSAU) 
+        MSSAU->wireOldPredecessorsToNewImmediatePredecessor( 
+            HoistTarget->getSingleSuccessor(), HoistCommonSucc, {HoistTarget}); 
+      // The new preheader dominates the loop header. 
+      DomTreeNode *PreheaderNode = DT->getNode(HoistCommonSucc); 
+      DomTreeNode *HeaderNode = DT->getNode(CurLoop->getHeader()); 
+      DT->changeImmediateDominator(HeaderNode, PreheaderNode); 
+      // The preheader hoist destination is now the new preheader, with the 
+      // exception of the hoist destination of this branch. 
+      for (auto &Pair : HoistDestinationMap) 
+        if (Pair.second == InitialPreheader && Pair.first != BI->getParent()) 
+          Pair.second = HoistCommonSucc; 
+    } 
+ 
+    // Now finally clone BI. 
+    ReplaceInstWithInst( 
+        HoistTarget->getTerminator(), 
+        BranchInst::Create(HoistTrueDest, HoistFalseDest, BI->getCondition())); 
+    ++NumClonedBranches; 
+ 
+    assert(CurLoop->getLoopPreheader() && 
+           "Hoisting blocks should not have destroyed preheader"); 
+    return HoistDestinationMap[BB]; 
+  } 
+}; 
+} // namespace 
+ 
 // Hoisting/sinking instruction out of a loop isn't always beneficial. It's only
 // only worthwhile if the destination block is actually colder than current
 // block.
@@ -817,205 +817,205 @@ static bool worthSinkOrHoistInst(Instruction &I, BasicBlock *DstBlock,
   return true;
 }
 
-/// Walk the specified region of the CFG (defined by all blocks dominated by
-/// the specified block, and that are in the current loop) in depth first
-/// order w.r.t the DominatorTree.  This allows us to visit definitions before
-/// uses, allowing us to hoist a loop body in one pass without iteration.
-///
-bool llvm::hoistRegion(DomTreeNode *N, AAResults *AA, LoopInfo *LI,
+/// Walk the specified region of the CFG (defined by all blocks dominated by 
+/// the specified block, and that are in the current loop) in depth first 
+/// order w.r.t the DominatorTree.  This allows us to visit definitions before 
+/// uses, allowing us to hoist a loop body in one pass without iteration. 
+/// 
+bool llvm::hoistRegion(DomTreeNode *N, AAResults *AA, LoopInfo *LI, 
                        DominatorTree *DT, BlockFrequencyInfo *BFI,
                        TargetLibraryInfo *TLI, Loop *CurLoop,
-                       AliasSetTracker *CurAST, MemorySSAUpdater *MSSAU,
-                       ScalarEvolution *SE, ICFLoopSafetyInfo *SafetyInfo,
-                       SinkAndHoistLICMFlags &Flags,
-                       OptimizationRemarkEmitter *ORE) {
-  // Verify inputs.
-  assert(N != nullptr && AA != nullptr && LI != nullptr && DT != nullptr &&
-         CurLoop != nullptr && SafetyInfo != nullptr &&
-         "Unexpected input to hoistRegion.");
-  assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) &&
-         "Either AliasSetTracker or MemorySSA should be initialized.");
-
-  ControlFlowHoister CFH(LI, DT, CurLoop, MSSAU);
-
-  // Keep track of instructions that have been hoisted, as they may need to be
-  // re-hoisted if they end up not dominating all of their uses.
-  SmallVector<Instruction *, 16> HoistedInstructions;
-
-  // For PHI hoisting to work we need to hoist blocks before their successors.
-  // We can do this by iterating through the blocks in the loop in reverse
-  // post-order.
-  LoopBlocksRPO Worklist(CurLoop);
-  Worklist.perform(LI);
-  bool Changed = false;
-  for (BasicBlock *BB : Worklist) {
-    // Only need to process the contents of this block if it is not part of a
-    // subloop (which would already have been processed).
-    if (inSubLoop(BB, CurLoop, LI))
-      continue;
-
-    for (BasicBlock::iterator II = BB->begin(), E = BB->end(); II != E;) {
-      Instruction &I = *II++;
-      // Try constant folding this instruction.  If all the operands are
-      // constants, it is technically hoistable, but it would be better to
-      // just fold it.
-      if (Constant *C = ConstantFoldInstruction(
-              &I, I.getModule()->getDataLayout(), TLI)) {
-        LLVM_DEBUG(dbgs() << "LICM folding inst: " << I << "  --> " << *C
-                          << '\n');
-        if (CurAST)
-          CurAST->copyValue(&I, C);
-        // FIXME MSSA: Such replacements may make accesses unoptimized (D51960).
-        I.replaceAllUsesWith(C);
-        if (isInstructionTriviallyDead(&I, TLI))
-          eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
-        Changed = true;
-        continue;
-      }
-
-      // Try hoisting the instruction out to the preheader.  We can only do
-      // this if all of the operands of the instruction are loop invariant and
+                       AliasSetTracker *CurAST, MemorySSAUpdater *MSSAU, 
+                       ScalarEvolution *SE, ICFLoopSafetyInfo *SafetyInfo, 
+                       SinkAndHoistLICMFlags &Flags, 
+                       OptimizationRemarkEmitter *ORE) { 
+  // Verify inputs. 
+  assert(N != nullptr && AA != nullptr && LI != nullptr && DT != nullptr && 
+         CurLoop != nullptr && SafetyInfo != nullptr && 
+         "Unexpected input to hoistRegion."); 
+  assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) && 
+         "Either AliasSetTracker or MemorySSA should be initialized."); 
+ 
+  ControlFlowHoister CFH(LI, DT, CurLoop, MSSAU); 
+ 
+  // Keep track of instructions that have been hoisted, as they may need to be 
+  // re-hoisted if they end up not dominating all of their uses. 
+  SmallVector<Instruction *, 16> HoistedInstructions; 
+ 
+  // For PHI hoisting to work we need to hoist blocks before their successors. 
+  // We can do this by iterating through the blocks in the loop in reverse 
+  // post-order. 
+  LoopBlocksRPO Worklist(CurLoop); 
+  Worklist.perform(LI); 
+  bool Changed = false; 
+  for (BasicBlock *BB : Worklist) { 
+    // Only need to process the contents of this block if it is not part of a 
+    // subloop (which would already have been processed). 
+    if (inSubLoop(BB, CurLoop, LI)) 
+      continue; 
+ 
+    for (BasicBlock::iterator II = BB->begin(), E = BB->end(); II != E;) { 
+      Instruction &I = *II++; 
+      // Try constant folding this instruction.  If all the operands are 
+      // constants, it is technically hoistable, but it would be better to 
+      // just fold it. 
+      if (Constant *C = ConstantFoldInstruction( 
+              &I, I.getModule()->getDataLayout(), TLI)) { 
+        LLVM_DEBUG(dbgs() << "LICM folding inst: " << I << "  --> " << *C 
+                          << '\n'); 
+        if (CurAST) 
+          CurAST->copyValue(&I, C); 
+        // FIXME MSSA: Such replacements may make accesses unoptimized (D51960). 
+        I.replaceAllUsesWith(C); 
+        if (isInstructionTriviallyDead(&I, TLI)) 
+          eraseInstruction(I, *SafetyInfo, CurAST, MSSAU); 
+        Changed = true; 
+        continue; 
+      } 
+ 
+      // Try hoisting the instruction out to the preheader.  We can only do 
+      // this if all of the operands of the instruction are loop invariant and 
       // if it is safe to hoist the instruction. We also check block frequency
       // to make sure instruction only gets hoisted into colder blocks.
-      // TODO: It may be safe to hoist if we are hoisting to a conditional block
-      // and we have accurately duplicated the control flow from the loop header
-      // to that block.
-      if (CurLoop->hasLoopInvariantOperands(&I) &&
-          canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, MSSAU, true, &Flags,
-                             ORE) &&
+      // TODO: It may be safe to hoist if we are hoisting to a conditional block 
+      // and we have accurately duplicated the control flow from the loop header 
+      // to that block. 
+      if (CurLoop->hasLoopInvariantOperands(&I) && 
+          canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, MSSAU, true, &Flags, 
+                             ORE) && 
           worthSinkOrHoistInst(I, CurLoop->getLoopPreheader(), ORE, BFI) &&
-          isSafeToExecuteUnconditionally(
-              I, DT, CurLoop, SafetyInfo, ORE,
-              CurLoop->getLoopPreheader()->getTerminator())) {
-        hoist(I, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo,
-              MSSAU, SE, ORE);
-        HoistedInstructions.push_back(&I);
-        Changed = true;
-        continue;
-      }
-
-      // Attempt to remove floating point division out of the loop by
-      // converting it to a reciprocal multiplication.
-      if (I.getOpcode() == Instruction::FDiv && I.hasAllowReciprocal() &&
-          CurLoop->isLoopInvariant(I.getOperand(1))) {
-        auto Divisor = I.getOperand(1);
-        auto One = llvm::ConstantFP::get(Divisor->getType(), 1.0);
-        auto ReciprocalDivisor = BinaryOperator::CreateFDiv(One, Divisor);
-        ReciprocalDivisor->setFastMathFlags(I.getFastMathFlags());
-        SafetyInfo->insertInstructionTo(ReciprocalDivisor, I.getParent());
-        ReciprocalDivisor->insertBefore(&I);
-
-        auto Product =
-            BinaryOperator::CreateFMul(I.getOperand(0), ReciprocalDivisor);
-        Product->setFastMathFlags(I.getFastMathFlags());
-        SafetyInfo->insertInstructionTo(Product, I.getParent());
-        Product->insertAfter(&I);
-        I.replaceAllUsesWith(Product);
-        eraseInstruction(I, *SafetyInfo, CurAST, MSSAU);
-
-        hoist(*ReciprocalDivisor, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB),
-              SafetyInfo, MSSAU, SE, ORE);
-        HoistedInstructions.push_back(ReciprocalDivisor);
-        Changed = true;
-        continue;
-      }
-
-      auto IsInvariantStart = [&](Instruction &I) {
-        using namespace PatternMatch;
-        return I.use_empty() &&
-               match(&I, m_Intrinsic<Intrinsic::invariant_start>());
-      };
-      auto MustExecuteWithoutWritesBefore = [&](Instruction &I) {
-        return SafetyInfo->isGuaranteedToExecute(I, DT, CurLoop) &&
-               SafetyInfo->doesNotWriteMemoryBefore(I, CurLoop);
-      };
-      if ((IsInvariantStart(I) || isGuard(&I)) &&
-          CurLoop->hasLoopInvariantOperands(&I) &&
-          MustExecuteWithoutWritesBefore(I)) {
-        hoist(I, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo,
-              MSSAU, SE, ORE);
-        HoistedInstructions.push_back(&I);
-        Changed = true;
-        continue;
-      }
-
-      if (PHINode *PN = dyn_cast<PHINode>(&I)) {
-        if (CFH.canHoistPHI(PN)) {
-          // Redirect incoming blocks first to ensure that we create hoisted
-          // versions of those blocks before we hoist the phi.
-          for (unsigned int i = 0; i < PN->getNumIncomingValues(); ++i)
-            PN->setIncomingBlock(
-                i, CFH.getOrCreateHoistedBlock(PN->getIncomingBlock(i)));
-          hoist(*PN, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo,
-                MSSAU, SE, ORE);
-          assert(DT->dominates(PN, BB) && "Conditional PHIs not expected");
-          Changed = true;
-          continue;
-        }
-      }
-
-      // Remember possibly hoistable branches so we can actually hoist them
-      // later if needed.
-      if (BranchInst *BI = dyn_cast<BranchInst>(&I))
-        CFH.registerPossiblyHoistableBranch(BI);
-    }
-  }
-
-  // If we hoisted instructions to a conditional block they may not dominate
-  // their uses that weren't hoisted (such as phis where some operands are not
-  // loop invariant). If so make them unconditional by moving them to their
-  // immediate dominator. We iterate through the instructions in reverse order
-  // which ensures that when we rehoist an instruction we rehoist its operands,
-  // and also keep track of where in the block we are rehoisting to to make sure
-  // that we rehoist instructions before the instructions that use them.
-  Instruction *HoistPoint = nullptr;
-  if (ControlFlowHoisting) {
-    for (Instruction *I : reverse(HoistedInstructions)) {
-      if (!llvm::all_of(I->uses(),
-                        [&](Use &U) { return DT->dominates(I, U); })) {
-        BasicBlock *Dominator =
-            DT->getNode(I->getParent())->getIDom()->getBlock();
-        if (!HoistPoint || !DT->dominates(HoistPoint->getParent(), Dominator)) {
-          if (HoistPoint)
-            assert(DT->dominates(Dominator, HoistPoint->getParent()) &&
-                   "New hoist point expected to dominate old hoist point");
-          HoistPoint = Dominator->getTerminator();
-        }
-        LLVM_DEBUG(dbgs() << "LICM rehoisting to "
+          isSafeToExecuteUnconditionally( 
+              I, DT, CurLoop, SafetyInfo, ORE, 
+              CurLoop->getLoopPreheader()->getTerminator())) { 
+        hoist(I, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo, 
+              MSSAU, SE, ORE); 
+        HoistedInstructions.push_back(&I); 
+        Changed = true; 
+        continue; 
+      } 
+ 
+      // Attempt to remove floating point division out of the loop by 
+      // converting it to a reciprocal multiplication. 
+      if (I.getOpcode() == Instruction::FDiv && I.hasAllowReciprocal() && 
+          CurLoop->isLoopInvariant(I.getOperand(1))) { 
+        auto Divisor = I.getOperand(1); 
+        auto One = llvm::ConstantFP::get(Divisor->getType(), 1.0); 
+        auto ReciprocalDivisor = BinaryOperator::CreateFDiv(One, Divisor); 
+        ReciprocalDivisor->setFastMathFlags(I.getFastMathFlags()); 
+        SafetyInfo->insertInstructionTo(ReciprocalDivisor, I.getParent()); 
+        ReciprocalDivisor->insertBefore(&I); 
+ 
+        auto Product = 
+            BinaryOperator::CreateFMul(I.getOperand(0), ReciprocalDivisor); 
+        Product->setFastMathFlags(I.getFastMathFlags()); 
+        SafetyInfo->insertInstructionTo(Product, I.getParent()); 
+        Product->insertAfter(&I); 
+        I.replaceAllUsesWith(Product); 
+        eraseInstruction(I, *SafetyInfo, CurAST, MSSAU); 
+ 
+        hoist(*ReciprocalDivisor, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), 
+              SafetyInfo, MSSAU, SE, ORE); 
+        HoistedInstructions.push_back(ReciprocalDivisor); 
+        Changed = true; 
+        continue; 
+      } 
+ 
+      auto IsInvariantStart = [&](Instruction &I) { 
+        using namespace PatternMatch; 
+        return I.use_empty() && 
+               match(&I, m_Intrinsic<Intrinsic::invariant_start>()); 
+      }; 
+      auto MustExecuteWithoutWritesBefore = [&](Instruction &I) { 
+        return SafetyInfo->isGuaranteedToExecute(I, DT, CurLoop) && 
+               SafetyInfo->doesNotWriteMemoryBefore(I, CurLoop); 
+      }; 
+      if ((IsInvariantStart(I) || isGuard(&I)) && 
+          CurLoop->hasLoopInvariantOperands(&I) && 
+          MustExecuteWithoutWritesBefore(I)) { 
+        hoist(I, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo, 
+              MSSAU, SE, ORE); 
+        HoistedInstructions.push_back(&I); 
+        Changed = true; 
+        continue; 
+      } 
+ 
+      if (PHINode *PN = dyn_cast<PHINode>(&I)) { 
+        if (CFH.canHoistPHI(PN)) { 
+          // Redirect incoming blocks first to ensure that we create hoisted 
+          // versions of those blocks before we hoist the phi. 
+          for (unsigned int i = 0; i < PN->getNumIncomingValues(); ++i) 
+            PN->setIncomingBlock( 
+                i, CFH.getOrCreateHoistedBlock(PN->getIncomingBlock(i))); 
+          hoist(*PN, DT, CurLoop, CFH.getOrCreateHoistedBlock(BB), SafetyInfo, 
+                MSSAU, SE, ORE); 
+          assert(DT->dominates(PN, BB) && "Conditional PHIs not expected"); 
+          Changed = true; 
+          continue; 
+        } 
+      } 
+ 
+      // Remember possibly hoistable branches so we can actually hoist them 
+      // later if needed. 
+      if (BranchInst *BI = dyn_cast<BranchInst>(&I)) 
+        CFH.registerPossiblyHoistableBranch(BI); 
+    } 
+  } 
+ 
+  // If we hoisted instructions to a conditional block they may not dominate 
+  // their uses that weren't hoisted (such as phis where some operands are not 
+  // loop invariant). If so make them unconditional by moving them to their 
+  // immediate dominator. We iterate through the instructions in reverse order 
+  // which ensures that when we rehoist an instruction we rehoist its operands, 
+  // and also keep track of where in the block we are rehoisting to to make sure 
+  // that we rehoist instructions before the instructions that use them. 
+  Instruction *HoistPoint = nullptr; 
+  if (ControlFlowHoisting) { 
+    for (Instruction *I : reverse(HoistedInstructions)) { 
+      if (!llvm::all_of(I->uses(), 
+                        [&](Use &U) { return DT->dominates(I, U); })) { 
+        BasicBlock *Dominator = 
+            DT->getNode(I->getParent())->getIDom()->getBlock(); 
+        if (!HoistPoint || !DT->dominates(HoistPoint->getParent(), Dominator)) { 
+          if (HoistPoint) 
+            assert(DT->dominates(Dominator, HoistPoint->getParent()) && 
+                   "New hoist point expected to dominate old hoist point"); 
+          HoistPoint = Dominator->getTerminator(); 
+        } 
+        LLVM_DEBUG(dbgs() << "LICM rehoisting to " 
                           << HoistPoint->getParent()->getNameOrAsOperand()
-                          << ": " << *I << "\n");
-        moveInstructionBefore(*I, *HoistPoint, *SafetyInfo, MSSAU, SE);
-        HoistPoint = I;
-        Changed = true;
-      }
-    }
-  }
-  if (MSSAU && VerifyMemorySSA)
-    MSSAU->getMemorySSA()->verifyMemorySSA();
-
-    // Now that we've finished hoisting make sure that LI and DT are still
-    // valid.
-#ifdef EXPENSIVE_CHECKS
-  if (Changed) {
-    assert(DT->verify(DominatorTree::VerificationLevel::Fast) &&
-           "Dominator tree verification failed");
-    LI->verify(*DT);
-  }
-#endif
-
-  return Changed;
-}
-
-// Return true if LI is invariant within scope of the loop. LI is invariant if
-// CurLoop is dominated by an invariant.start representing the same memory
-// location and size as the memory location LI loads from, and also the
-// invariant.start has no uses.
-static bool isLoadInvariantInLoop(LoadInst *LI, DominatorTree *DT,
-                                  Loop *CurLoop) {
-  Value *Addr = LI->getOperand(0);
-  const DataLayout &DL = LI->getModule()->getDataLayout();
+                          << ": " << *I << "\n"); 
+        moveInstructionBefore(*I, *HoistPoint, *SafetyInfo, MSSAU, SE); 
+        HoistPoint = I; 
+        Changed = true; 
+      } 
+    } 
+  } 
+  if (MSSAU && VerifyMemorySSA) 
+    MSSAU->getMemorySSA()->verifyMemorySSA(); 
+ 
+    // Now that we've finished hoisting make sure that LI and DT are still 
+    // valid. 
+#ifdef EXPENSIVE_CHECKS 
+  if (Changed) { 
+    assert(DT->verify(DominatorTree::VerificationLevel::Fast) && 
+           "Dominator tree verification failed"); 
+    LI->verify(*DT); 
+  } 
+#endif 
+ 
+  return Changed; 
+} 
+ 
+// Return true if LI is invariant within scope of the loop. LI is invariant if 
+// CurLoop is dominated by an invariant.start representing the same memory 
+// location and size as the memory location LI loads from, and also the 
+// invariant.start has no uses. 
+static bool isLoadInvariantInLoop(LoadInst *LI, DominatorTree *DT, 
+                                  Loop *CurLoop) { 
+  Value *Addr = LI->getOperand(0); 
+  const DataLayout &DL = LI->getModule()->getDataLayout(); 
   const TypeSize LocSizeInBits = DL.getTypeSizeInBits(LI->getType());
-
+ 
   // It is not currently possible for clang to generate an invariant.start
   // intrinsic with scalable vector types because we don't support thread local
   // sizeless types and we don't permit sizeless types in structs or classes.
@@ -1028,166 +1028,166 @@ static bool isLoadInvariantInLoop(LoadInst *LI, DominatorTree *DT,
   if (LocSizeInBits.isScalable())
     return false;
 
-  // if the type is i8 addrspace(x)*, we know this is the type of
-  // llvm.invariant.start operand
-  auto *PtrInt8Ty = PointerType::get(Type::getInt8Ty(LI->getContext()),
-                                     LI->getPointerAddressSpace());
-  unsigned BitcastsVisited = 0;
-  // Look through bitcasts until we reach the i8* type (this is invariant.start
-  // operand type).
-  while (Addr->getType() != PtrInt8Ty) {
-    auto *BC = dyn_cast<BitCastInst>(Addr);
-    // Avoid traversing high number of bitcast uses.
-    if (++BitcastsVisited > MaxNumUsesTraversed || !BC)
-      return false;
-    Addr = BC->getOperand(0);
-  }
-
-  unsigned UsesVisited = 0;
-  // Traverse all uses of the load operand value, to see if invariant.start is
-  // one of the uses, and whether it dominates the load instruction.
-  for (auto *U : Addr->users()) {
-    // Avoid traversing for Load operand with high number of users.
-    if (++UsesVisited > MaxNumUsesTraversed)
-      return false;
-    IntrinsicInst *II = dyn_cast<IntrinsicInst>(U);
-    // If there are escaping uses of invariant.start instruction, the load maybe
-    // non-invariant.
-    if (!II || II->getIntrinsicID() != Intrinsic::invariant_start ||
-        !II->use_empty())
-      continue;
+  // if the type is i8 addrspace(x)*, we know this is the type of 
+  // llvm.invariant.start operand 
+  auto *PtrInt8Ty = PointerType::get(Type::getInt8Ty(LI->getContext()), 
+                                     LI->getPointerAddressSpace()); 
+  unsigned BitcastsVisited = 0; 
+  // Look through bitcasts until we reach the i8* type (this is invariant.start 
+  // operand type). 
+  while (Addr->getType() != PtrInt8Ty) { 
+    auto *BC = dyn_cast<BitCastInst>(Addr); 
+    // Avoid traversing high number of bitcast uses. 
+    if (++BitcastsVisited > MaxNumUsesTraversed || !BC) 
+      return false; 
+    Addr = BC->getOperand(0); 
+  } 
+ 
+  unsigned UsesVisited = 0; 
+  // Traverse all uses of the load operand value, to see if invariant.start is 
+  // one of the uses, and whether it dominates the load instruction. 
+  for (auto *U : Addr->users()) { 
+    // Avoid traversing for Load operand with high number of users. 
+    if (++UsesVisited > MaxNumUsesTraversed) 
+      return false; 
+    IntrinsicInst *II = dyn_cast<IntrinsicInst>(U); 
+    // If there are escaping uses of invariant.start instruction, the load maybe 
+    // non-invariant. 
+    if (!II || II->getIntrinsicID() != Intrinsic::invariant_start || 
+        !II->use_empty()) 
+      continue; 
     ConstantInt *InvariantSize = cast<ConstantInt>(II->getArgOperand(0));
     // The intrinsic supports having a -1 argument for variable sized objects
     // so we should check for that here.
     if (InvariantSize->isNegative())
       continue;
     uint64_t InvariantSizeInBits = InvariantSize->getSExtValue() * 8;
-    // Confirm the invariant.start location size contains the load operand size
-    // in bits. Also, the invariant.start should dominate the load, and we
-    // should not hoist the load out of a loop that contains this dominating
-    // invariant.start.
+    // Confirm the invariant.start location size contains the load operand size 
+    // in bits. Also, the invariant.start should dominate the load, and we 
+    // should not hoist the load out of a loop that contains this dominating 
+    // invariant.start. 
     if (LocSizeInBits.getFixedSize() <= InvariantSizeInBits &&
-        DT->properlyDominates(II->getParent(), CurLoop->getHeader()))
-      return true;
-  }
-
-  return false;
-}
-
-namespace {
-/// Return true if-and-only-if we know how to (mechanically) both hoist and
-/// sink a given instruction out of a loop.  Does not address legality
-/// concerns such as aliasing or speculation safety.
-bool isHoistableAndSinkableInst(Instruction &I) {
-  // Only these instructions are hoistable/sinkable.
-  return (isa<LoadInst>(I) || isa<StoreInst>(I) || isa<CallInst>(I) ||
-          isa<FenceInst>(I) || isa<CastInst>(I) || isa<UnaryOperator>(I) ||
-          isa<BinaryOperator>(I) || isa<SelectInst>(I) ||
-          isa<GetElementPtrInst>(I) || isa<CmpInst>(I) ||
-          isa<InsertElementInst>(I) || isa<ExtractElementInst>(I) ||
-          isa<ShuffleVectorInst>(I) || isa<ExtractValueInst>(I) ||
-          isa<InsertValueInst>(I) || isa<FreezeInst>(I));
-}
-/// Return true if all of the alias sets within this AST are known not to
-/// contain a Mod, or if MSSA knows thare are no MemoryDefs in the loop.
-bool isReadOnly(AliasSetTracker *CurAST, const MemorySSAUpdater *MSSAU,
-                const Loop *L) {
-  if (CurAST) {
-    for (AliasSet &AS : *CurAST) {
-      if (!AS.isForwardingAliasSet() && AS.isMod()) {
-        return false;
-      }
-    }
-    return true;
-  } else { /*MSSAU*/
-    for (auto *BB : L->getBlocks())
-      if (MSSAU->getMemorySSA()->getBlockDefs(BB))
-        return false;
-    return true;
-  }
-}
-
-/// Return true if I is the only Instruction with a MemoryAccess in L.
-bool isOnlyMemoryAccess(const Instruction *I, const Loop *L,
-                        const MemorySSAUpdater *MSSAU) {
-  for (auto *BB : L->getBlocks())
-    if (auto *Accs = MSSAU->getMemorySSA()->getBlockAccesses(BB)) {
-      int NotAPhi = 0;
-      for (const auto &Acc : *Accs) {
-        if (isa<MemoryPhi>(&Acc))
-          continue;
-        const auto *MUD = cast<MemoryUseOrDef>(&Acc);
-        if (MUD->getMemoryInst() != I || NotAPhi++ == 1)
-          return false;
-      }
-    }
-  return true;
-}
-}
-
-bool llvm::canSinkOrHoistInst(Instruction &I, AAResults *AA, DominatorTree *DT,
-                              Loop *CurLoop, AliasSetTracker *CurAST,
-                              MemorySSAUpdater *MSSAU,
-                              bool TargetExecutesOncePerLoop,
-                              SinkAndHoistLICMFlags *Flags,
-                              OptimizationRemarkEmitter *ORE) {
+        DT->properlyDominates(II->getParent(), CurLoop->getHeader())) 
+      return true; 
+  } 
+ 
+  return false; 
+} 
+ 
+namespace { 
+/// Return true if-and-only-if we know how to (mechanically) both hoist and 
+/// sink a given instruction out of a loop.  Does not address legality 
+/// concerns such as aliasing or speculation safety. 
+bool isHoistableAndSinkableInst(Instruction &I) { 
+  // Only these instructions are hoistable/sinkable. 
+  return (isa<LoadInst>(I) || isa<StoreInst>(I) || isa<CallInst>(I) || 
+          isa<FenceInst>(I) || isa<CastInst>(I) || isa<UnaryOperator>(I) || 
+          isa<BinaryOperator>(I) || isa<SelectInst>(I) || 
+          isa<GetElementPtrInst>(I) || isa<CmpInst>(I) || 
+          isa<InsertElementInst>(I) || isa<ExtractElementInst>(I) || 
+          isa<ShuffleVectorInst>(I) || isa<ExtractValueInst>(I) || 
+          isa<InsertValueInst>(I) || isa<FreezeInst>(I)); 
+} 
+/// Return true if all of the alias sets within this AST are known not to 
+/// contain a Mod, or if MSSA knows thare are no MemoryDefs in the loop. 
+bool isReadOnly(AliasSetTracker *CurAST, const MemorySSAUpdater *MSSAU, 
+                const Loop *L) { 
+  if (CurAST) { 
+    for (AliasSet &AS : *CurAST) { 
+      if (!AS.isForwardingAliasSet() && AS.isMod()) { 
+        return false; 
+      } 
+    } 
+    return true; 
+  } else { /*MSSAU*/ 
+    for (auto *BB : L->getBlocks()) 
+      if (MSSAU->getMemorySSA()->getBlockDefs(BB)) 
+        return false; 
+    return true; 
+  } 
+} 
+ 
+/// Return true if I is the only Instruction with a MemoryAccess in L. 
+bool isOnlyMemoryAccess(const Instruction *I, const Loop *L, 
+                        const MemorySSAUpdater *MSSAU) { 
+  for (auto *BB : L->getBlocks()) 
+    if (auto *Accs = MSSAU->getMemorySSA()->getBlockAccesses(BB)) { 
+      int NotAPhi = 0; 
+      for (const auto &Acc : *Accs) { 
+        if (isa<MemoryPhi>(&Acc)) 
+          continue; 
+        const auto *MUD = cast<MemoryUseOrDef>(&Acc); 
+        if (MUD->getMemoryInst() != I || NotAPhi++ == 1) 
+          return false; 
+      } 
+    } 
+  return true; 
+} 
+} 
+ 
+bool llvm::canSinkOrHoistInst(Instruction &I, AAResults *AA, DominatorTree *DT, 
+                              Loop *CurLoop, AliasSetTracker *CurAST, 
+                              MemorySSAUpdater *MSSAU, 
+                              bool TargetExecutesOncePerLoop, 
+                              SinkAndHoistLICMFlags *Flags, 
+                              OptimizationRemarkEmitter *ORE) { 
   assert(((CurAST != nullptr) ^ (MSSAU != nullptr)) &&
          "Either AliasSetTracker or MemorySSA should be initialized.");
 
-  // If we don't understand the instruction, bail early.
-  if (!isHoistableAndSinkableInst(I))
-    return false;
-
-  MemorySSA *MSSA = MSSAU ? MSSAU->getMemorySSA() : nullptr;
-  if (MSSA)
-    assert(Flags != nullptr && "Flags cannot be null.");
-
-  // Loads have extra constraints we have to verify before we can hoist them.
-  if (LoadInst *LI = dyn_cast<LoadInst>(&I)) {
-    if (!LI->isUnordered())
-      return false; // Don't sink/hoist volatile or ordered atomic loads!
-
-    // Loads from constant memory are always safe to move, even if they end up
-    // in the same alias set as something that ends up being modified.
-    if (AA->pointsToConstantMemory(LI->getOperand(0)))
-      return true;
-    if (LI->hasMetadata(LLVMContext::MD_invariant_load))
-      return true;
-
-    if (LI->isAtomic() && !TargetExecutesOncePerLoop)
-      return false; // Don't risk duplicating unordered loads
-
-    // This checks for an invariant.start dominating the load.
-    if (isLoadInvariantInLoop(LI, DT, CurLoop))
-      return true;
-
-    bool Invalidated;
-    if (CurAST)
-      Invalidated = pointerInvalidatedByLoop(MemoryLocation::get(LI), CurAST,
-                                             CurLoop, AA);
-    else
-      Invalidated = pointerInvalidatedByLoopWithMSSA(
+  // If we don't understand the instruction, bail early. 
+  if (!isHoistableAndSinkableInst(I)) 
+    return false; 
+ 
+  MemorySSA *MSSA = MSSAU ? MSSAU->getMemorySSA() : nullptr; 
+  if (MSSA) 
+    assert(Flags != nullptr && "Flags cannot be null."); 
+ 
+  // Loads have extra constraints we have to verify before we can hoist them. 
+  if (LoadInst *LI = dyn_cast<LoadInst>(&I)) { 
+    if (!LI->isUnordered()) 
+      return false; // Don't sink/hoist volatile or ordered atomic loads! 
+ 
+    // Loads from constant memory are always safe to move, even if they end up 
+    // in the same alias set as something that ends up being modified. 
+    if (AA->pointsToConstantMemory(LI->getOperand(0))) 
+      return true; 
+    if (LI->hasMetadata(LLVMContext::MD_invariant_load)) 
+      return true; 
+ 
+    if (LI->isAtomic() && !TargetExecutesOncePerLoop) 
+      return false; // Don't risk duplicating unordered loads 
+ 
+    // This checks for an invariant.start dominating the load. 
+    if (isLoadInvariantInLoop(LI, DT, CurLoop)) 
+      return true; 
+ 
+    bool Invalidated; 
+    if (CurAST) 
+      Invalidated = pointerInvalidatedByLoop(MemoryLocation::get(LI), CurAST, 
+                                             CurLoop, AA); 
+    else 
+      Invalidated = pointerInvalidatedByLoopWithMSSA( 
           MSSA, cast<MemoryUse>(MSSA->getMemoryAccess(LI)), CurLoop, I, *Flags);
-    // Check loop-invariant address because this may also be a sinkable load
-    // whose address is not necessarily loop-invariant.
-    if (ORE && Invalidated && CurLoop->isLoopInvariant(LI->getPointerOperand()))
-      ORE->emit([&]() {
-        return OptimizationRemarkMissed(
-                   DEBUG_TYPE, "LoadWithLoopInvariantAddressInvalidated", LI)
-               << "failed to move load with loop-invariant address "
-                  "because the loop may invalidate its value";
-      });
-
-    return !Invalidated;
-  } else if (CallInst *CI = dyn_cast<CallInst>(&I)) {
-    // Don't sink or hoist dbg info; it's legal, but not useful.
-    if (isa<DbgInfoIntrinsic>(I))
-      return false;
-
-    // Don't sink calls which can throw.
-    if (CI->mayThrow())
-      return false;
-
+    // Check loop-invariant address because this may also be a sinkable load 
+    // whose address is not necessarily loop-invariant. 
+    if (ORE && Invalidated && CurLoop->isLoopInvariant(LI->getPointerOperand())) 
+      ORE->emit([&]() { 
+        return OptimizationRemarkMissed( 
+                   DEBUG_TYPE, "LoadWithLoopInvariantAddressInvalidated", LI) 
+               << "failed to move load with loop-invariant address " 
+                  "because the loop may invalidate its value"; 
+      }); 
+ 
+    return !Invalidated; 
+  } else if (CallInst *CI = dyn_cast<CallInst>(&I)) { 
+    // Don't sink or hoist dbg info; it's legal, but not useful. 
+    if (isa<DbgInfoIntrinsic>(I)) 
+      return false; 
+ 
+    // Don't sink calls which can throw. 
+    if (CI->mayThrow()) 
+      return false; 
+ 
     // Convergent attribute has been used on operations that involve
     // inter-thread communication which results are implicitly affected by the
     // enclosing control flows. It is not safe to hoist or sink such operations
@@ -1195,526 +1195,526 @@ bool llvm::canSinkOrHoistInst(Instruction &I, AAResults *AA, DominatorTree *DT,
     if (CI->isConvergent())
       return false;
 
-    using namespace PatternMatch;
-    if (match(CI, m_Intrinsic<Intrinsic::assume>()))
-      // Assumes don't actually alias anything or throw
-      return true;
-
-    if (match(CI, m_Intrinsic<Intrinsic::experimental_widenable_condition>()))
-      // Widenable conditions don't actually alias anything or throw
-      return true;
-
-    // Handle simple cases by querying alias analysis.
-    FunctionModRefBehavior Behavior = AA->getModRefBehavior(CI);
-    if (Behavior == FMRB_DoesNotAccessMemory)
-      return true;
-    if (AAResults::onlyReadsMemory(Behavior)) {
-      // A readonly argmemonly function only reads from memory pointed to by
-      // it's arguments with arbitrary offsets.  If we can prove there are no
-      // writes to this memory in the loop, we can hoist or sink.
-      if (AAResults::onlyAccessesArgPointees(Behavior)) {
-        // TODO: expand to writeable arguments
-        for (Value *Op : CI->arg_operands())
-          if (Op->getType()->isPointerTy()) {
-            bool Invalidated;
-            if (CurAST)
-              Invalidated = pointerInvalidatedByLoop(
+    using namespace PatternMatch; 
+    if (match(CI, m_Intrinsic<Intrinsic::assume>())) 
+      // Assumes don't actually alias anything or throw 
+      return true; 
+ 
+    if (match(CI, m_Intrinsic<Intrinsic::experimental_widenable_condition>())) 
+      // Widenable conditions don't actually alias anything or throw 
+      return true; 
+ 
+    // Handle simple cases by querying alias analysis. 
+    FunctionModRefBehavior Behavior = AA->getModRefBehavior(CI); 
+    if (Behavior == FMRB_DoesNotAccessMemory) 
+      return true; 
+    if (AAResults::onlyReadsMemory(Behavior)) { 
+      // A readonly argmemonly function only reads from memory pointed to by 
+      // it's arguments with arbitrary offsets.  If we can prove there are no 
+      // writes to this memory in the loop, we can hoist or sink. 
+      if (AAResults::onlyAccessesArgPointees(Behavior)) { 
+        // TODO: expand to writeable arguments 
+        for (Value *Op : CI->arg_operands()) 
+          if (Op->getType()->isPointerTy()) { 
+            bool Invalidated; 
+            if (CurAST) 
+              Invalidated = pointerInvalidatedByLoop( 
                   MemoryLocation::getBeforeOrAfter(Op), CurAST, CurLoop, AA);
-            else
-              Invalidated = pointerInvalidatedByLoopWithMSSA(
+            else 
+              Invalidated = pointerInvalidatedByLoopWithMSSA( 
                   MSSA, cast<MemoryUse>(MSSA->getMemoryAccess(CI)), CurLoop, I,
-                  *Flags);
-            if (Invalidated)
-              return false;
-          }
-        return true;
-      }
-
-      // If this call only reads from memory and there are no writes to memory
-      // in the loop, we can hoist or sink the call as appropriate.
-      if (isReadOnly(CurAST, MSSAU, CurLoop))
-        return true;
-    }
-
-    // FIXME: This should use mod/ref information to see if we can hoist or
-    // sink the call.
-
-    return false;
-  } else if (auto *FI = dyn_cast<FenceInst>(&I)) {
-    // Fences alias (most) everything to provide ordering.  For the moment,
-    // just give up if there are any other memory operations in the loop.
-    if (CurAST) {
-      auto Begin = CurAST->begin();
-      assert(Begin != CurAST->end() && "must contain FI");
-      if (std::next(Begin) != CurAST->end())
-        // constant memory for instance, TODO: handle better
-        return false;
-      auto *UniqueI = Begin->getUniqueInstruction();
-      if (!UniqueI)
-        // other memory op, give up
-        return false;
-      (void)FI; // suppress unused variable warning
-      assert(UniqueI == FI && "AS must contain FI");
-      return true;
-    } else // MSSAU
-      return isOnlyMemoryAccess(FI, CurLoop, MSSAU);
-  } else if (auto *SI = dyn_cast<StoreInst>(&I)) {
-    if (!SI->isUnordered())
-      return false; // Don't sink/hoist volatile or ordered atomic store!
-
-    // We can only hoist a store that we can prove writes a value which is not
-    // read or overwritten within the loop.  For those cases, we fallback to
-    // load store promotion instead.  TODO: We can extend this to cases where
-    // there is exactly one write to the location and that write dominates an
-    // arbitrary number of reads in the loop.
-    if (CurAST) {
-      auto &AS = CurAST->getAliasSetFor(MemoryLocation::get(SI));
-
-      if (AS.isRef() || !AS.isMustAlias())
-        // Quick exit test, handled by the full path below as well.
-        return false;
-      auto *UniqueI = AS.getUniqueInstruction();
-      if (!UniqueI)
-        // other memory op, give up
-        return false;
-      assert(UniqueI == SI && "AS must contain SI");
-      return true;
-    } else { // MSSAU
-      if (isOnlyMemoryAccess(SI, CurLoop, MSSAU))
-        return true;
+                  *Flags); 
+            if (Invalidated) 
+              return false; 
+          } 
+        return true; 
+      } 
+ 
+      // If this call only reads from memory and there are no writes to memory 
+      // in the loop, we can hoist or sink the call as appropriate. 
+      if (isReadOnly(CurAST, MSSAU, CurLoop)) 
+        return true; 
+    } 
+ 
+    // FIXME: This should use mod/ref information to see if we can hoist or 
+    // sink the call. 
+ 
+    return false; 
+  } else if (auto *FI = dyn_cast<FenceInst>(&I)) { 
+    // Fences alias (most) everything to provide ordering.  For the moment, 
+    // just give up if there are any other memory operations in the loop. 
+    if (CurAST) { 
+      auto Begin = CurAST->begin(); 
+      assert(Begin != CurAST->end() && "must contain FI"); 
+      if (std::next(Begin) != CurAST->end()) 
+        // constant memory for instance, TODO: handle better 
+        return false; 
+      auto *UniqueI = Begin->getUniqueInstruction(); 
+      if (!UniqueI) 
+        // other memory op, give up 
+        return false; 
+      (void)FI; // suppress unused variable warning 
+      assert(UniqueI == FI && "AS must contain FI"); 
+      return true; 
+    } else // MSSAU 
+      return isOnlyMemoryAccess(FI, CurLoop, MSSAU); 
+  } else if (auto *SI = dyn_cast<StoreInst>(&I)) { 
+    if (!SI->isUnordered()) 
+      return false; // Don't sink/hoist volatile or ordered atomic store! 
+ 
+    // We can only hoist a store that we can prove writes a value which is not 
+    // read or overwritten within the loop.  For those cases, we fallback to 
+    // load store promotion instead.  TODO: We can extend this to cases where 
+    // there is exactly one write to the location and that write dominates an 
+    // arbitrary number of reads in the loop. 
+    if (CurAST) { 
+      auto &AS = CurAST->getAliasSetFor(MemoryLocation::get(SI)); 
+ 
+      if (AS.isRef() || !AS.isMustAlias()) 
+        // Quick exit test, handled by the full path below as well. 
+        return false; 
+      auto *UniqueI = AS.getUniqueInstruction(); 
+      if (!UniqueI) 
+        // other memory op, give up 
+        return false; 
+      assert(UniqueI == SI && "AS must contain SI"); 
+      return true; 
+    } else { // MSSAU 
+      if (isOnlyMemoryAccess(SI, CurLoop, MSSAU)) 
+        return true; 
       // If there are more accesses than the Promotion cap or no "quota" to
       // check clobber, then give up as we're not walking a list that long.
       if (Flags->tooManyMemoryAccesses() || Flags->tooManyClobberingCalls())
-        return false;
-      // If there are interfering Uses (i.e. their defining access is in the
-      // loop), or ordered loads (stored as Defs!), don't move this store.
-      // Could do better here, but this is conservatively correct.
-      // TODO: Cache set of Uses on the first walk in runOnLoop, update when
-      // moving accesses. Can also extend to dominating uses.
-      auto *SIMD = MSSA->getMemoryAccess(SI);
-      for (auto *BB : CurLoop->getBlocks())
-        if (auto *Accesses = MSSA->getBlockAccesses(BB)) {
-          for (const auto &MA : *Accesses)
-            if (const auto *MU = dyn_cast<MemoryUse>(&MA)) {
-              auto *MD = MU->getDefiningAccess();
-              if (!MSSA->isLiveOnEntryDef(MD) &&
-                  CurLoop->contains(MD->getBlock()))
-                return false;
-              // Disable hoisting past potentially interfering loads. Optimized
-              // Uses may point to an access outside the loop, as getClobbering
-              // checks the previous iteration when walking the backedge.
-              // FIXME: More precise: no Uses that alias SI.
+        return false; 
+      // If there are interfering Uses (i.e. their defining access is in the 
+      // loop), or ordered loads (stored as Defs!), don't move this store. 
+      // Could do better here, but this is conservatively correct. 
+      // TODO: Cache set of Uses on the first walk in runOnLoop, update when 
+      // moving accesses. Can also extend to dominating uses. 
+      auto *SIMD = MSSA->getMemoryAccess(SI); 
+      for (auto *BB : CurLoop->getBlocks()) 
+        if (auto *Accesses = MSSA->getBlockAccesses(BB)) { 
+          for (const auto &MA : *Accesses) 
+            if (const auto *MU = dyn_cast<MemoryUse>(&MA)) { 
+              auto *MD = MU->getDefiningAccess(); 
+              if (!MSSA->isLiveOnEntryDef(MD) && 
+                  CurLoop->contains(MD->getBlock())) 
+                return false; 
+              // Disable hoisting past potentially interfering loads. Optimized 
+              // Uses may point to an access outside the loop, as getClobbering 
+              // checks the previous iteration when walking the backedge. 
+              // FIXME: More precise: no Uses that alias SI. 
               if (!Flags->getIsSink() && !MSSA->dominates(SIMD, MU))
-                return false;
-            } else if (const auto *MD = dyn_cast<MemoryDef>(&MA)) {
-              if (auto *LI = dyn_cast<LoadInst>(MD->getMemoryInst())) {
-                (void)LI; // Silence warning.
-                assert(!LI->isUnordered() && "Expected unordered load");
-                return false;
-              }
-              // Any call, while it may not be clobbering SI, it may be a use.
-              if (auto *CI = dyn_cast<CallInst>(MD->getMemoryInst())) {
-                // Check if the call may read from the memory locattion written
-                // to by SI. Check CI's attributes and arguments; the number of
-                // such checks performed is limited above by NoOfMemAccTooLarge.
-                ModRefInfo MRI = AA->getModRefInfo(CI, MemoryLocation::get(SI));
-                if (isModOrRefSet(MRI))
-                  return false;
-              }
-            }
-        }
-      auto *Source = MSSA->getSkipSelfWalker()->getClobberingMemoryAccess(SI);
+                return false; 
+            } else if (const auto *MD = dyn_cast<MemoryDef>(&MA)) { 
+              if (auto *LI = dyn_cast<LoadInst>(MD->getMemoryInst())) { 
+                (void)LI; // Silence warning. 
+                assert(!LI->isUnordered() && "Expected unordered load"); 
+                return false; 
+              } 
+              // Any call, while it may not be clobbering SI, it may be a use. 
+              if (auto *CI = dyn_cast<CallInst>(MD->getMemoryInst())) { 
+                // Check if the call may read from the memory locattion written 
+                // to by SI. Check CI's attributes and arguments; the number of 
+                // such checks performed is limited above by NoOfMemAccTooLarge. 
+                ModRefInfo MRI = AA->getModRefInfo(CI, MemoryLocation::get(SI)); 
+                if (isModOrRefSet(MRI)) 
+                  return false; 
+              } 
+            } 
+        } 
+      auto *Source = MSSA->getSkipSelfWalker()->getClobberingMemoryAccess(SI); 
       Flags->incrementClobberingCalls();
-      // If there are no clobbering Defs in the loop, store is safe to hoist.
-      return MSSA->isLiveOnEntryDef(Source) ||
-             !CurLoop->contains(Source->getBlock());
-    }
-  }
-
-  assert(!I.mayReadOrWriteMemory() && "unhandled aliasing");
-
-  // We've established mechanical ability and aliasing, it's up to the caller
-  // to check fault safety
-  return true;
-}
-
-/// Returns true if a PHINode is a trivially replaceable with an
-/// Instruction.
-/// This is true when all incoming values are that instruction.
-/// This pattern occurs most often with LCSSA PHI nodes.
-///
-static bool isTriviallyReplaceablePHI(const PHINode &PN, const Instruction &I) {
-  for (const Value *IncValue : PN.incoming_values())
-    if (IncValue != &I)
-      return false;
-
-  return true;
-}
-
-/// Return true if the instruction is free in the loop.
-static bool isFreeInLoop(const Instruction &I, const Loop *CurLoop,
-                         const TargetTransformInfo *TTI) {
-
-  if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(&I)) {
-    if (TTI->getUserCost(GEP, TargetTransformInfo::TCK_SizeAndLatency) !=
-        TargetTransformInfo::TCC_Free)
-      return false;
-    // For a GEP, we cannot simply use getUserCost because currently it
-    // optimistically assume that a GEP will fold into addressing mode
-    // regardless of its users.
-    const BasicBlock *BB = GEP->getParent();
-    for (const User *U : GEP->users()) {
-      const Instruction *UI = cast<Instruction>(U);
-      if (CurLoop->contains(UI) &&
-          (BB != UI->getParent() ||
-           (!isa<StoreInst>(UI) && !isa<LoadInst>(UI))))
-        return false;
-    }
-    return true;
-  } else
-    return TTI->getUserCost(&I, TargetTransformInfo::TCK_SizeAndLatency) ==
-           TargetTransformInfo::TCC_Free;
-}
-
-/// Return true if the only users of this instruction are outside of
-/// the loop. If this is true, we can sink the instruction to the exit
-/// blocks of the loop.
-///
-/// We also return true if the instruction could be folded away in lowering.
-/// (e.g.,  a GEP can be folded into a load as an addressing mode in the loop).
-static bool isNotUsedOrFreeInLoop(const Instruction &I, const Loop *CurLoop,
-                                  const LoopSafetyInfo *SafetyInfo,
-                                  TargetTransformInfo *TTI, bool &FreeInLoop) {
-  const auto &BlockColors = SafetyInfo->getBlockColors();
-  bool IsFree = isFreeInLoop(I, CurLoop, TTI);
-  for (const User *U : I.users()) {
-    const Instruction *UI = cast<Instruction>(U);
-    if (const PHINode *PN = dyn_cast<PHINode>(UI)) {
-      const BasicBlock *BB = PN->getParent();
-      // We cannot sink uses in catchswitches.
-      if (isa<CatchSwitchInst>(BB->getTerminator()))
-        return false;
-
-      // We need to sink a callsite to a unique funclet.  Avoid sinking if the
-      // phi use is too muddled.
-      if (isa<CallInst>(I))
-        if (!BlockColors.empty() &&
-            BlockColors.find(const_cast<BasicBlock *>(BB))->second.size() != 1)
-          return false;
-    }
-
-    if (CurLoop->contains(UI)) {
-      if (IsFree) {
-        FreeInLoop = true;
-        continue;
-      }
-      return false;
-    }
-  }
-  return true;
-}
-
-static Instruction *cloneInstructionInExitBlock(
-    Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo *LI,
-    const LoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU) {
-  Instruction *New;
-  if (auto *CI = dyn_cast<CallInst>(&I)) {
-    const auto &BlockColors = SafetyInfo->getBlockColors();
-
-    // Sinking call-sites need to be handled differently from other
-    // instructions.  The cloned call-site needs a funclet bundle operand
-    // appropriate for its location in the CFG.
-    SmallVector<OperandBundleDef, 1> OpBundles;
-    for (unsigned BundleIdx = 0, BundleEnd = CI->getNumOperandBundles();
-         BundleIdx != BundleEnd; ++BundleIdx) {
-      OperandBundleUse Bundle = CI->getOperandBundleAt(BundleIdx);
-      if (Bundle.getTagID() == LLVMContext::OB_funclet)
-        continue;
-
-      OpBundles.emplace_back(Bundle);
-    }
-
-    if (!BlockColors.empty()) {
-      const ColorVector &CV = BlockColors.find(&ExitBlock)->second;
-      assert(CV.size() == 1 && "non-unique color for exit block!");
-      BasicBlock *BBColor = CV.front();
-      Instruction *EHPad = BBColor->getFirstNonPHI();
-      if (EHPad->isEHPad())
-        OpBundles.emplace_back("funclet", EHPad);
-    }
-
-    New = CallInst::Create(CI, OpBundles);
-  } else {
-    New = I.clone();
-  }
-
-  ExitBlock.getInstList().insert(ExitBlock.getFirstInsertionPt(), New);
-  if (!I.getName().empty())
-    New->setName(I.getName() + ".le");
-
-  if (MSSAU && MSSAU->getMemorySSA()->getMemoryAccess(&I)) {
-    // Create a new MemoryAccess and let MemorySSA set its defining access.
-    MemoryAccess *NewMemAcc = MSSAU->createMemoryAccessInBB(
-        New, nullptr, New->getParent(), MemorySSA::Beginning);
-    if (NewMemAcc) {
-      if (auto *MemDef = dyn_cast<MemoryDef>(NewMemAcc))
-        MSSAU->insertDef(MemDef, /*RenameUses=*/true);
-      else {
-        auto *MemUse = cast<MemoryUse>(NewMemAcc);
-        MSSAU->insertUse(MemUse, /*RenameUses=*/true);
-      }
-    }
-  }
-
-  // Build LCSSA PHI nodes for any in-loop operands. Note that this is
-  // particularly cheap because we can rip off the PHI node that we're
-  // replacing for the number and blocks of the predecessors.
-  // OPT: If this shows up in a profile, we can instead finish sinking all
-  // invariant instructions, and then walk their operands to re-establish
-  // LCSSA. That will eliminate creating PHI nodes just to nuke them when
-  // sinking bottom-up.
-  for (User::op_iterator OI = New->op_begin(), OE = New->op_end(); OI != OE;
-       ++OI)
-    if (Instruction *OInst = dyn_cast<Instruction>(*OI))
-      if (Loop *OLoop = LI->getLoopFor(OInst->getParent()))
-        if (!OLoop->contains(&PN)) {
-          PHINode *OpPN =
-              PHINode::Create(OInst->getType(), PN.getNumIncomingValues(),
-                              OInst->getName() + ".lcssa", &ExitBlock.front());
-          for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
-            OpPN->addIncoming(OInst, PN.getIncomingBlock(i));
-          *OI = OpPN;
-        }
-  return New;
-}
-
-static void eraseInstruction(Instruction &I, ICFLoopSafetyInfo &SafetyInfo,
-                             AliasSetTracker *AST, MemorySSAUpdater *MSSAU) {
-  if (AST)
-    AST->deleteValue(&I);
-  if (MSSAU)
-    MSSAU->removeMemoryAccess(&I);
-  SafetyInfo.removeInstruction(&I);
-  I.eraseFromParent();
-}
-
-static void moveInstructionBefore(Instruction &I, Instruction &Dest,
-                                  ICFLoopSafetyInfo &SafetyInfo,
-                                  MemorySSAUpdater *MSSAU,
-                                  ScalarEvolution *SE) {
-  SafetyInfo.removeInstruction(&I);
-  SafetyInfo.insertInstructionTo(&I, Dest.getParent());
-  I.moveBefore(&Dest);
-  if (MSSAU)
-    if (MemoryUseOrDef *OldMemAcc = cast_or_null<MemoryUseOrDef>(
-            MSSAU->getMemorySSA()->getMemoryAccess(&I)))
-      MSSAU->moveToPlace(OldMemAcc, Dest.getParent(),
-                         MemorySSA::BeforeTerminator);
-  if (SE)
-    SE->forgetValue(&I);
-}
-
-static Instruction *sinkThroughTriviallyReplaceablePHI(
-    PHINode *TPN, Instruction *I, LoopInfo *LI,
-    SmallDenseMap<BasicBlock *, Instruction *, 32> &SunkCopies,
-    const LoopSafetyInfo *SafetyInfo, const Loop *CurLoop,
-    MemorySSAUpdater *MSSAU) {
-  assert(isTriviallyReplaceablePHI(*TPN, *I) &&
-         "Expect only trivially replaceable PHI");
-  BasicBlock *ExitBlock = TPN->getParent();
-  Instruction *New;
-  auto It = SunkCopies.find(ExitBlock);
-  if (It != SunkCopies.end())
-    New = It->second;
-  else
-    New = SunkCopies[ExitBlock] = cloneInstructionInExitBlock(
-        *I, *ExitBlock, *TPN, LI, SafetyInfo, MSSAU);
-  return New;
-}
-
-static bool canSplitPredecessors(PHINode *PN, LoopSafetyInfo *SafetyInfo) {
-  BasicBlock *BB = PN->getParent();
-  if (!BB->canSplitPredecessors())
-    return false;
-  // It's not impossible to split EHPad blocks, but if BlockColors already exist
-  // it require updating BlockColors for all offspring blocks accordingly. By
-  // skipping such corner case, we can make updating BlockColors after splitting
-  // predecessor fairly simple.
-  if (!SafetyInfo->getBlockColors().empty() && BB->getFirstNonPHI()->isEHPad())
-    return false;
-  for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
-    BasicBlock *BBPred = *PI;
-    if (isa<IndirectBrInst>(BBPred->getTerminator()) ||
-        isa<CallBrInst>(BBPred->getTerminator()))
-      return false;
-  }
-  return true;
-}
-
-static void splitPredecessorsOfLoopExit(PHINode *PN, DominatorTree *DT,
-                                        LoopInfo *LI, const Loop *CurLoop,
-                                        LoopSafetyInfo *SafetyInfo,
-                                        MemorySSAUpdater *MSSAU) {
-#ifndef NDEBUG
-  SmallVector<BasicBlock *, 32> ExitBlocks;
-  CurLoop->getUniqueExitBlocks(ExitBlocks);
-  SmallPtrSet<BasicBlock *, 32> ExitBlockSet(ExitBlocks.begin(),
-                                             ExitBlocks.end());
-#endif
-  BasicBlock *ExitBB = PN->getParent();
-  assert(ExitBlockSet.count(ExitBB) && "Expect the PHI is in an exit block.");
-
-  // Split predecessors of the loop exit to make instructions in the loop are
-  // exposed to exit blocks through trivially replaceable PHIs while keeping the
-  // loop in the canonical form where each predecessor of each exit block should
-  // be contained within the loop. For example, this will convert the loop below
-  // from
-  //
-  // LB1:
-  //   %v1 =
-  //   br %LE, %LB2
-  // LB2:
-  //   %v2 =
-  //   br %LE, %LB1
-  // LE:
-  //   %p = phi [%v1, %LB1], [%v2, %LB2] <-- non-trivially replaceable
-  //
-  // to
-  //
-  // LB1:
-  //   %v1 =
-  //   br %LE.split, %LB2
-  // LB2:
-  //   %v2 =
-  //   br %LE.split2, %LB1
-  // LE.split:
-  //   %p1 = phi [%v1, %LB1]  <-- trivially replaceable
-  //   br %LE
-  // LE.split2:
-  //   %p2 = phi [%v2, %LB2]  <-- trivially replaceable
-  //   br %LE
-  // LE:
-  //   %p = phi [%p1, %LE.split], [%p2, %LE.split2]
-  //
-  const auto &BlockColors = SafetyInfo->getBlockColors();
-  SmallSetVector<BasicBlock *, 8> PredBBs(pred_begin(ExitBB), pred_end(ExitBB));
-  while (!PredBBs.empty()) {
-    BasicBlock *PredBB = *PredBBs.begin();
-    assert(CurLoop->contains(PredBB) &&
-           "Expect all predecessors are in the loop");
-    if (PN->getBasicBlockIndex(PredBB) >= 0) {
-      BasicBlock *NewPred = SplitBlockPredecessors(
-          ExitBB, PredBB, ".split.loop.exit", DT, LI, MSSAU, true);
-      // Since we do not allow splitting EH-block with BlockColors in
-      // canSplitPredecessors(), we can simply assign predecessor's color to
-      // the new block.
-      if (!BlockColors.empty())
-        // Grab a reference to the ColorVector to be inserted before getting the
-        // reference to the vector we are copying because inserting the new
-        // element in BlockColors might cause the map to be reallocated.
-        SafetyInfo->copyColors(NewPred, PredBB);
-    }
-    PredBBs.remove(PredBB);
-  }
-}
-
-/// When an instruction is found to only be used outside of the loop, this
-/// function moves it to the exit blocks and patches up SSA form as needed.
-/// This method is guaranteed to remove the original instruction from its
-/// position, and may either delete it or move it to outside of the loop.
-///
-static bool sink(Instruction &I, LoopInfo *LI, DominatorTree *DT,
+      // If there are no clobbering Defs in the loop, store is safe to hoist. 
+      return MSSA->isLiveOnEntryDef(Source) || 
+             !CurLoop->contains(Source->getBlock()); 
+    } 
+  } 
+ 
+  assert(!I.mayReadOrWriteMemory() && "unhandled aliasing"); 
+ 
+  // We've established mechanical ability and aliasing, it's up to the caller 
+  // to check fault safety 
+  return true; 
+} 
+ 
+/// Returns true if a PHINode is a trivially replaceable with an 
+/// Instruction. 
+/// This is true when all incoming values are that instruction. 
+/// This pattern occurs most often with LCSSA PHI nodes. 
+/// 
+static bool isTriviallyReplaceablePHI(const PHINode &PN, const Instruction &I) { 
+  for (const Value *IncValue : PN.incoming_values()) 
+    if (IncValue != &I) 
+      return false; 
+ 
+  return true; 
+} 
+ 
+/// Return true if the instruction is free in the loop. 
+static bool isFreeInLoop(const Instruction &I, const Loop *CurLoop, 
+                         const TargetTransformInfo *TTI) { 
+ 
+  if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(&I)) { 
+    if (TTI->getUserCost(GEP, TargetTransformInfo::TCK_SizeAndLatency) != 
+        TargetTransformInfo::TCC_Free) 
+      return false; 
+    // For a GEP, we cannot simply use getUserCost because currently it 
+    // optimistically assume that a GEP will fold into addressing mode 
+    // regardless of its users. 
+    const BasicBlock *BB = GEP->getParent(); 
+    for (const User *U : GEP->users()) { 
+      const Instruction *UI = cast<Instruction>(U); 
+      if (CurLoop->contains(UI) && 
+          (BB != UI->getParent() || 
+           (!isa<StoreInst>(UI) && !isa<LoadInst>(UI)))) 
+        return false; 
+    } 
+    return true; 
+  } else 
+    return TTI->getUserCost(&I, TargetTransformInfo::TCK_SizeAndLatency) == 
+           TargetTransformInfo::TCC_Free; 
+} 
+ 
+/// Return true if the only users of this instruction are outside of 
+/// the loop. If this is true, we can sink the instruction to the exit 
+/// blocks of the loop. 
+/// 
+/// We also return true if the instruction could be folded away in lowering. 
+/// (e.g.,  a GEP can be folded into a load as an addressing mode in the loop). 
+static bool isNotUsedOrFreeInLoop(const Instruction &I, const Loop *CurLoop, 
+                                  const LoopSafetyInfo *SafetyInfo, 
+                                  TargetTransformInfo *TTI, bool &FreeInLoop) { 
+  const auto &BlockColors = SafetyInfo->getBlockColors(); 
+  bool IsFree = isFreeInLoop(I, CurLoop, TTI); 
+  for (const User *U : I.users()) { 
+    const Instruction *UI = cast<Instruction>(U); 
+    if (const PHINode *PN = dyn_cast<PHINode>(UI)) { 
+      const BasicBlock *BB = PN->getParent(); 
+      // We cannot sink uses in catchswitches. 
+      if (isa<CatchSwitchInst>(BB->getTerminator())) 
+        return false; 
+ 
+      // We need to sink a callsite to a unique funclet.  Avoid sinking if the 
+      // phi use is too muddled. 
+      if (isa<CallInst>(I)) 
+        if (!BlockColors.empty() && 
+            BlockColors.find(const_cast<BasicBlock *>(BB))->second.size() != 1) 
+          return false; 
+    } 
+ 
+    if (CurLoop->contains(UI)) { 
+      if (IsFree) { 
+        FreeInLoop = true; 
+        continue; 
+      } 
+      return false; 
+    } 
+  } 
+  return true; 
+} 
+ 
+static Instruction *cloneInstructionInExitBlock( 
+    Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo *LI, 
+    const LoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU) { 
+  Instruction *New; 
+  if (auto *CI = dyn_cast<CallInst>(&I)) { 
+    const auto &BlockColors = SafetyInfo->getBlockColors(); 
+ 
+    // Sinking call-sites need to be handled differently from other 
+    // instructions.  The cloned call-site needs a funclet bundle operand 
+    // appropriate for its location in the CFG. 
+    SmallVector<OperandBundleDef, 1> OpBundles; 
+    for (unsigned BundleIdx = 0, BundleEnd = CI->getNumOperandBundles(); 
+         BundleIdx != BundleEnd; ++BundleIdx) { 
+      OperandBundleUse Bundle = CI->getOperandBundleAt(BundleIdx); 
+      if (Bundle.getTagID() == LLVMContext::OB_funclet) 
+        continue; 
+ 
+      OpBundles.emplace_back(Bundle); 
+    } 
+ 
+    if (!BlockColors.empty()) { 
+      const ColorVector &CV = BlockColors.find(&ExitBlock)->second; 
+      assert(CV.size() == 1 && "non-unique color for exit block!"); 
+      BasicBlock *BBColor = CV.front(); 
+      Instruction *EHPad = BBColor->getFirstNonPHI(); 
+      if (EHPad->isEHPad()) 
+        OpBundles.emplace_back("funclet", EHPad); 
+    } 
+ 
+    New = CallInst::Create(CI, OpBundles); 
+  } else { 
+    New = I.clone(); 
+  } 
+ 
+  ExitBlock.getInstList().insert(ExitBlock.getFirstInsertionPt(), New); 
+  if (!I.getName().empty()) 
+    New->setName(I.getName() + ".le"); 
+ 
+  if (MSSAU && MSSAU->getMemorySSA()->getMemoryAccess(&I)) { 
+    // Create a new MemoryAccess and let MemorySSA set its defining access. 
+    MemoryAccess *NewMemAcc = MSSAU->createMemoryAccessInBB( 
+        New, nullptr, New->getParent(), MemorySSA::Beginning); 
+    if (NewMemAcc) { 
+      if (auto *MemDef = dyn_cast<MemoryDef>(NewMemAcc)) 
+        MSSAU->insertDef(MemDef, /*RenameUses=*/true); 
+      else { 
+        auto *MemUse = cast<MemoryUse>(NewMemAcc); 
+        MSSAU->insertUse(MemUse, /*RenameUses=*/true); 
+      } 
+    } 
+  } 
+ 
+  // Build LCSSA PHI nodes for any in-loop operands. Note that this is 
+  // particularly cheap because we can rip off the PHI node that we're 
+  // replacing for the number and blocks of the predecessors. 
+  // OPT: If this shows up in a profile, we can instead finish sinking all 
+  // invariant instructions, and then walk their operands to re-establish 
+  // LCSSA. That will eliminate creating PHI nodes just to nuke them when 
+  // sinking bottom-up. 
+  for (User::op_iterator OI = New->op_begin(), OE = New->op_end(); OI != OE; 
+       ++OI) 
+    if (Instruction *OInst = dyn_cast<Instruction>(*OI)) 
+      if (Loop *OLoop = LI->getLoopFor(OInst->getParent())) 
+        if (!OLoop->contains(&PN)) { 
+          PHINode *OpPN = 
+              PHINode::Create(OInst->getType(), PN.getNumIncomingValues(), 
+                              OInst->getName() + ".lcssa", &ExitBlock.front()); 
+          for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) 
+            OpPN->addIncoming(OInst, PN.getIncomingBlock(i)); 
+          *OI = OpPN; 
+        } 
+  return New; 
+} 
+ 
+static void eraseInstruction(Instruction &I, ICFLoopSafetyInfo &SafetyInfo, 
+                             AliasSetTracker *AST, MemorySSAUpdater *MSSAU) { 
+  if (AST) 
+    AST->deleteValue(&I); 
+  if (MSSAU) 
+    MSSAU->removeMemoryAccess(&I); 
+  SafetyInfo.removeInstruction(&I); 
+  I.eraseFromParent(); 
+} 
+ 
+static void moveInstructionBefore(Instruction &I, Instruction &Dest, 
+                                  ICFLoopSafetyInfo &SafetyInfo, 
+                                  MemorySSAUpdater *MSSAU, 
+                                  ScalarEvolution *SE) { 
+  SafetyInfo.removeInstruction(&I); 
+  SafetyInfo.insertInstructionTo(&I, Dest.getParent()); 
+  I.moveBefore(&Dest); 
+  if (MSSAU) 
+    if (MemoryUseOrDef *OldMemAcc = cast_or_null<MemoryUseOrDef>( 
+            MSSAU->getMemorySSA()->getMemoryAccess(&I))) 
+      MSSAU->moveToPlace(OldMemAcc, Dest.getParent(), 
+                         MemorySSA::BeforeTerminator); 
+  if (SE) 
+    SE->forgetValue(&I); 
+} 
+ 
+static Instruction *sinkThroughTriviallyReplaceablePHI( 
+    PHINode *TPN, Instruction *I, LoopInfo *LI, 
+    SmallDenseMap<BasicBlock *, Instruction *, 32> &SunkCopies, 
+    const LoopSafetyInfo *SafetyInfo, const Loop *CurLoop, 
+    MemorySSAUpdater *MSSAU) { 
+  assert(isTriviallyReplaceablePHI(*TPN, *I) && 
+         "Expect only trivially replaceable PHI"); 
+  BasicBlock *ExitBlock = TPN->getParent(); 
+  Instruction *New; 
+  auto It = SunkCopies.find(ExitBlock); 
+  if (It != SunkCopies.end()) 
+    New = It->second; 
+  else 
+    New = SunkCopies[ExitBlock] = cloneInstructionInExitBlock( 
+        *I, *ExitBlock, *TPN, LI, SafetyInfo, MSSAU); 
+  return New; 
+} 
+ 
+static bool canSplitPredecessors(PHINode *PN, LoopSafetyInfo *SafetyInfo) { 
+  BasicBlock *BB = PN->getParent(); 
+  if (!BB->canSplitPredecessors()) 
+    return false; 
+  // It's not impossible to split EHPad blocks, but if BlockColors already exist 
+  // it require updating BlockColors for all offspring blocks accordingly. By 
+  // skipping such corner case, we can make updating BlockColors after splitting 
+  // predecessor fairly simple. 
+  if (!SafetyInfo->getBlockColors().empty() && BB->getFirstNonPHI()->isEHPad()) 
+    return false; 
+  for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) { 
+    BasicBlock *BBPred = *PI; 
+    if (isa<IndirectBrInst>(BBPred->getTerminator()) || 
+        isa<CallBrInst>(BBPred->getTerminator())) 
+      return false; 
+  } 
+  return true; 
+} 
+ 
+static void splitPredecessorsOfLoopExit(PHINode *PN, DominatorTree *DT, 
+                                        LoopInfo *LI, const Loop *CurLoop, 
+                                        LoopSafetyInfo *SafetyInfo, 
+                                        MemorySSAUpdater *MSSAU) { 
+#ifndef NDEBUG 
+  SmallVector<BasicBlock *, 32> ExitBlocks; 
+  CurLoop->getUniqueExitBlocks(ExitBlocks); 
+  SmallPtrSet<BasicBlock *, 32> ExitBlockSet(ExitBlocks.begin(), 
+                                             ExitBlocks.end()); 
+#endif 
+  BasicBlock *ExitBB = PN->getParent(); 
+  assert(ExitBlockSet.count(ExitBB) && "Expect the PHI is in an exit block."); 
+ 
+  // Split predecessors of the loop exit to make instructions in the loop are 
+  // exposed to exit blocks through trivially replaceable PHIs while keeping the 
+  // loop in the canonical form where each predecessor of each exit block should 
+  // be contained within the loop. For example, this will convert the loop below 
+  // from 
+  // 
+  // LB1: 
+  //   %v1 = 
+  //   br %LE, %LB2 
+  // LB2: 
+  //   %v2 = 
+  //   br %LE, %LB1 
+  // LE: 
+  //   %p = phi [%v1, %LB1], [%v2, %LB2] <-- non-trivially replaceable 
+  // 
+  // to 
+  // 
+  // LB1: 
+  //   %v1 = 
+  //   br %LE.split, %LB2 
+  // LB2: 
+  //   %v2 = 
+  //   br %LE.split2, %LB1 
+  // LE.split: 
+  //   %p1 = phi [%v1, %LB1]  <-- trivially replaceable 
+  //   br %LE 
+  // LE.split2: 
+  //   %p2 = phi [%v2, %LB2]  <-- trivially replaceable 
+  //   br %LE 
+  // LE: 
+  //   %p = phi [%p1, %LE.split], [%p2, %LE.split2] 
+  // 
+  const auto &BlockColors = SafetyInfo->getBlockColors(); 
+  SmallSetVector<BasicBlock *, 8> PredBBs(pred_begin(ExitBB), pred_end(ExitBB)); 
+  while (!PredBBs.empty()) { 
+    BasicBlock *PredBB = *PredBBs.begin(); 
+    assert(CurLoop->contains(PredBB) && 
+           "Expect all predecessors are in the loop"); 
+    if (PN->getBasicBlockIndex(PredBB) >= 0) { 
+      BasicBlock *NewPred = SplitBlockPredecessors( 
+          ExitBB, PredBB, ".split.loop.exit", DT, LI, MSSAU, true); 
+      // Since we do not allow splitting EH-block with BlockColors in 
+      // canSplitPredecessors(), we can simply assign predecessor's color to 
+      // the new block. 
+      if (!BlockColors.empty()) 
+        // Grab a reference to the ColorVector to be inserted before getting the 
+        // reference to the vector we are copying because inserting the new 
+        // element in BlockColors might cause the map to be reallocated. 
+        SafetyInfo->copyColors(NewPred, PredBB); 
+    } 
+    PredBBs.remove(PredBB); 
+  } 
+} 
+ 
+/// When an instruction is found to only be used outside of the loop, this 
+/// function moves it to the exit blocks and patches up SSA form as needed. 
+/// This method is guaranteed to remove the original instruction from its 
+/// position, and may either delete it or move it to outside of the loop. 
+/// 
+static bool sink(Instruction &I, LoopInfo *LI, DominatorTree *DT, 
                  BlockFrequencyInfo *BFI, const Loop *CurLoop,
                  ICFLoopSafetyInfo *SafetyInfo, MemorySSAUpdater *MSSAU,
                  OptimizationRemarkEmitter *ORE) {
-  LLVM_DEBUG(dbgs() << "LICM sinking instruction: " << I << "\n");
-  ORE->emit([&]() {
-    return OptimizationRemark(DEBUG_TYPE, "InstSunk", &I)
-           << "sinking " << ore::NV("Inst", &I);
-  });
-  bool Changed = false;
-  if (isa<LoadInst>(I))
-    ++NumMovedLoads;
-  else if (isa<CallInst>(I))
-    ++NumMovedCalls;
-  ++NumSunk;
-
-  // Iterate over users to be ready for actual sinking. Replace users via
-  // unreachable blocks with undef and make all user PHIs trivially replaceable.
-  SmallPtrSet<Instruction *, 8> VisitedUsers;
-  for (Value::user_iterator UI = I.user_begin(), UE = I.user_end(); UI != UE;) {
-    auto *User = cast<Instruction>(*UI);
-    Use &U = UI.getUse();
-    ++UI;
-
-    if (VisitedUsers.count(User) || CurLoop->contains(User))
-      continue;
-
-    if (!DT->isReachableFromEntry(User->getParent())) {
-      U = UndefValue::get(I.getType());
-      Changed = true;
-      continue;
-    }
-
-    // The user must be a PHI node.
-    PHINode *PN = cast<PHINode>(User);
-
-    // Surprisingly, instructions can be used outside of loops without any
-    // exits.  This can only happen in PHI nodes if the incoming block is
-    // unreachable.
-    BasicBlock *BB = PN->getIncomingBlock(U);
-    if (!DT->isReachableFromEntry(BB)) {
-      U = UndefValue::get(I.getType());
-      Changed = true;
-      continue;
-    }
-
-    VisitedUsers.insert(PN);
-    if (isTriviallyReplaceablePHI(*PN, I))
-      continue;
-
-    if (!canSplitPredecessors(PN, SafetyInfo))
-      return Changed;
-
-    // Split predecessors of the PHI so that we can make users trivially
-    // replaceable.
-    splitPredecessorsOfLoopExit(PN, DT, LI, CurLoop, SafetyInfo, MSSAU);
-
-    // Should rebuild the iterators, as they may be invalidated by
-    // splitPredecessorsOfLoopExit().
-    UI = I.user_begin();
-    UE = I.user_end();
-  }
-
-  if (VisitedUsers.empty())
-    return Changed;
-
-#ifndef NDEBUG
-  SmallVector<BasicBlock *, 32> ExitBlocks;
-  CurLoop->getUniqueExitBlocks(ExitBlocks);
-  SmallPtrSet<BasicBlock *, 32> ExitBlockSet(ExitBlocks.begin(),
-                                             ExitBlocks.end());
-#endif
-
-  // Clones of this instruction. Don't create more than one per exit block!
-  SmallDenseMap<BasicBlock *, Instruction *, 32> SunkCopies;
-
-  // If this instruction is only used outside of the loop, then all users are
-  // PHI nodes in exit blocks due to LCSSA form. Just RAUW them with clones of
-  // the instruction.
+  LLVM_DEBUG(dbgs() << "LICM sinking instruction: " << I << "\n"); 
+  ORE->emit([&]() { 
+    return OptimizationRemark(DEBUG_TYPE, "InstSunk", &I) 
+           << "sinking " << ore::NV("Inst", &I); 
+  }); 
+  bool Changed = false; 
+  if (isa<LoadInst>(I)) 
+    ++NumMovedLoads; 
+  else if (isa<CallInst>(I)) 
+    ++NumMovedCalls; 
+  ++NumSunk; 
+ 
+  // Iterate over users to be ready for actual sinking. Replace users via 
+  // unreachable blocks with undef and make all user PHIs trivially replaceable. 
+  SmallPtrSet<Instruction *, 8> VisitedUsers; 
+  for (Value::user_iterator UI = I.user_begin(), UE = I.user_end(); UI != UE;) { 
+    auto *User = cast<Instruction>(*UI); 
+    Use &U = UI.getUse(); 
+    ++UI; 
+ 
+    if (VisitedUsers.count(User) || CurLoop->contains(User)) 
+      continue; 
+ 
+    if (!DT->isReachableFromEntry(User->getParent())) { 
+      U = UndefValue::get(I.getType()); 
+      Changed = true; 
+      continue; 
+    } 
+ 
+    // The user must be a PHI node. 
+    PHINode *PN = cast<PHINode>(User); 
+ 
+    // Surprisingly, instructions can be used outside of loops without any 
+    // exits.  This can only happen in PHI nodes if the incoming block is 
+    // unreachable. 
+    BasicBlock *BB = PN->getIncomingBlock(U); 
+    if (!DT->isReachableFromEntry(BB)) { 
+      U = UndefValue::get(I.getType()); 
+      Changed = true; 
+      continue; 
+    } 
+ 
+    VisitedUsers.insert(PN); 
+    if (isTriviallyReplaceablePHI(*PN, I)) 
+      continue; 
+ 
+    if (!canSplitPredecessors(PN, SafetyInfo)) 
+      return Changed; 
+ 
+    // Split predecessors of the PHI so that we can make users trivially 
+    // replaceable. 
+    splitPredecessorsOfLoopExit(PN, DT, LI, CurLoop, SafetyInfo, MSSAU); 
+ 
+    // Should rebuild the iterators, as they may be invalidated by 
+    // splitPredecessorsOfLoopExit(). 
+    UI = I.user_begin(); 
+    UE = I.user_end(); 
+  } 
+ 
+  if (VisitedUsers.empty()) 
+    return Changed; 
+ 
+#ifndef NDEBUG 
+  SmallVector<BasicBlock *, 32> ExitBlocks; 
+  CurLoop->getUniqueExitBlocks(ExitBlocks); 
+  SmallPtrSet<BasicBlock *, 32> ExitBlockSet(ExitBlocks.begin(), 
+                                             ExitBlocks.end()); 
+#endif 
+ 
+  // Clones of this instruction. Don't create more than one per exit block! 
+  SmallDenseMap<BasicBlock *, Instruction *, 32> SunkCopies; 
+ 
+  // If this instruction is only used outside of the loop, then all users are 
+  // PHI nodes in exit blocks due to LCSSA form. Just RAUW them with clones of 
+  // the instruction. 
   // First check if I is worth sinking for all uses. Sink only when it is worth
   // across all uses.
-  SmallSetVector<User*, 8> Users(I.user_begin(), I.user_end());
+  SmallSetVector<User*, 8> Users(I.user_begin(), I.user_end()); 
   SmallVector<PHINode *, 8> ExitPNs;
-  for (auto *UI : Users) {
-    auto *User = cast<Instruction>(UI);
-
-    if (CurLoop->contains(User))
-      continue;
-
-    PHINode *PN = cast<PHINode>(User);
-    assert(ExitBlockSet.count(PN->getParent()) &&
-           "The LCSSA PHI is not in an exit block!");
+  for (auto *UI : Users) { 
+    auto *User = cast<Instruction>(UI); 
+ 
+    if (CurLoop->contains(User)) 
+      continue; 
+ 
+    PHINode *PN = cast<PHINode>(User); 
+    assert(ExitBlockSet.count(PN->getParent()) && 
+           "The LCSSA PHI is not in an exit block!"); 
     if (!worthSinkOrHoistInst(I, PN->getParent(), ORE, BFI)) {
       return Changed;
     }
@@ -1724,622 +1724,622 @@ static bool sink(Instruction &I, LoopInfo *LI, DominatorTree *DT,
 
   for (auto *PN : ExitPNs) {
 
-    // The PHI must be trivially replaceable.
-    Instruction *New = sinkThroughTriviallyReplaceablePHI(
-        PN, &I, LI, SunkCopies, SafetyInfo, CurLoop, MSSAU);
-    PN->replaceAllUsesWith(New);
-    eraseInstruction(*PN, *SafetyInfo, nullptr, nullptr);
-    Changed = true;
-  }
-  return Changed;
-}
-
-/// When an instruction is found to only use loop invariant operands that
-/// is safe to hoist, this instruction is called to do the dirty work.
-///
-static void hoist(Instruction &I, const DominatorTree *DT, const Loop *CurLoop,
-                  BasicBlock *Dest, ICFLoopSafetyInfo *SafetyInfo,
-                  MemorySSAUpdater *MSSAU, ScalarEvolution *SE,
-                  OptimizationRemarkEmitter *ORE) {
+    // The PHI must be trivially replaceable. 
+    Instruction *New = sinkThroughTriviallyReplaceablePHI( 
+        PN, &I, LI, SunkCopies, SafetyInfo, CurLoop, MSSAU); 
+    PN->replaceAllUsesWith(New); 
+    eraseInstruction(*PN, *SafetyInfo, nullptr, nullptr); 
+    Changed = true; 
+  } 
+  return Changed; 
+} 
+ 
+/// When an instruction is found to only use loop invariant operands that 
+/// is safe to hoist, this instruction is called to do the dirty work. 
+/// 
+static void hoist(Instruction &I, const DominatorTree *DT, const Loop *CurLoop, 
+                  BasicBlock *Dest, ICFLoopSafetyInfo *SafetyInfo, 
+                  MemorySSAUpdater *MSSAU, ScalarEvolution *SE, 
+                  OptimizationRemarkEmitter *ORE) { 
   LLVM_DEBUG(dbgs() << "LICM hoisting to " << Dest->getNameOrAsOperand() << ": "
                     << I << "\n");
-  ORE->emit([&]() {
-    return OptimizationRemark(DEBUG_TYPE, "Hoisted", &I) << "hoisting "
-                                                         << ore::NV("Inst", &I);
-  });
-
-  // Metadata can be dependent on conditions we are hoisting above.
-  // Conservatively strip all metadata on the instruction unless we were
-  // guaranteed to execute I if we entered the loop, in which case the metadata
-  // is valid in the loop preheader.
-  if (I.hasMetadataOtherThanDebugLoc() &&
-      // The check on hasMetadataOtherThanDebugLoc is to prevent us from burning
-      // time in isGuaranteedToExecute if we don't actually have anything to
-      // drop.  It is a compile time optimization, not required for correctness.
-      !SafetyInfo->isGuaranteedToExecute(I, DT, CurLoop))
-    I.dropUnknownNonDebugMetadata();
-
-  if (isa<PHINode>(I))
-    // Move the new node to the end of the phi list in the destination block.
-    moveInstructionBefore(I, *Dest->getFirstNonPHI(), *SafetyInfo, MSSAU, SE);
-  else
-    // Move the new node to the destination block, before its terminator.
-    moveInstructionBefore(I, *Dest->getTerminator(), *SafetyInfo, MSSAU, SE);
-
+  ORE->emit([&]() { 
+    return OptimizationRemark(DEBUG_TYPE, "Hoisted", &I) << "hoisting " 
+                                                         << ore::NV("Inst", &I); 
+  }); 
+ 
+  // Metadata can be dependent on conditions we are hoisting above. 
+  // Conservatively strip all metadata on the instruction unless we were 
+  // guaranteed to execute I if we entered the loop, in which case the metadata 
+  // is valid in the loop preheader. 
+  if (I.hasMetadataOtherThanDebugLoc() && 
+      // The check on hasMetadataOtherThanDebugLoc is to prevent us from burning 
+      // time in isGuaranteedToExecute if we don't actually have anything to 
+      // drop.  It is a compile time optimization, not required for correctness. 
+      !SafetyInfo->isGuaranteedToExecute(I, DT, CurLoop)) 
+    I.dropUnknownNonDebugMetadata(); 
+ 
+  if (isa<PHINode>(I)) 
+    // Move the new node to the end of the phi list in the destination block. 
+    moveInstructionBefore(I, *Dest->getFirstNonPHI(), *SafetyInfo, MSSAU, SE); 
+  else 
+    // Move the new node to the destination block, before its terminator. 
+    moveInstructionBefore(I, *Dest->getTerminator(), *SafetyInfo, MSSAU, SE); 
+ 
   I.updateLocationAfterHoist();
-
-  if (isa<LoadInst>(I))
-    ++NumMovedLoads;
-  else if (isa<CallInst>(I))
-    ++NumMovedCalls;
-  ++NumHoisted;
-}
-
-/// Only sink or hoist an instruction if it is not a trapping instruction,
-/// or if the instruction is known not to trap when moved to the preheader.
-/// or if it is a trapping instruction and is guaranteed to execute.
-static bool isSafeToExecuteUnconditionally(Instruction &Inst,
-                                           const DominatorTree *DT,
-                                           const Loop *CurLoop,
-                                           const LoopSafetyInfo *SafetyInfo,
-                                           OptimizationRemarkEmitter *ORE,
-                                           const Instruction *CtxI) {
-  if (isSafeToSpeculativelyExecute(&Inst, CtxI, DT))
-    return true;
-
-  bool GuaranteedToExecute =
-      SafetyInfo->isGuaranteedToExecute(Inst, DT, CurLoop);
-
-  if (!GuaranteedToExecute) {
-    auto *LI = dyn_cast<LoadInst>(&Inst);
-    if (LI && CurLoop->isLoopInvariant(LI->getPointerOperand()))
-      ORE->emit([&]() {
-        return OptimizationRemarkMissed(
-                   DEBUG_TYPE, "LoadWithLoopInvariantAddressCondExecuted", LI)
-               << "failed to hoist load with loop-invariant address "
-                  "because load is conditionally executed";
-      });
-  }
-
-  return GuaranteedToExecute;
-}
-
-namespace {
-class LoopPromoter : public LoadAndStorePromoter {
-  Value *SomePtr; // Designated pointer to store to.
-  const SmallSetVector<Value *, 8> &PointerMustAliases;
-  SmallVectorImpl<BasicBlock *> &LoopExitBlocks;
-  SmallVectorImpl<Instruction *> &LoopInsertPts;
-  SmallVectorImpl<MemoryAccess *> &MSSAInsertPts;
-  PredIteratorCache &PredCache;
+ 
+  if (isa<LoadInst>(I)) 
+    ++NumMovedLoads; 
+  else if (isa<CallInst>(I)) 
+    ++NumMovedCalls; 
+  ++NumHoisted; 
+} 
+ 
+/// Only sink or hoist an instruction if it is not a trapping instruction, 
+/// or if the instruction is known not to trap when moved to the preheader. 
+/// or if it is a trapping instruction and is guaranteed to execute. 
+static bool isSafeToExecuteUnconditionally(Instruction &Inst, 
+                                           const DominatorTree *DT, 
+                                           const Loop *CurLoop, 
+                                           const LoopSafetyInfo *SafetyInfo, 
+                                           OptimizationRemarkEmitter *ORE, 
+                                           const Instruction *CtxI) { 
+  if (isSafeToSpeculativelyExecute(&Inst, CtxI, DT)) 
+    return true; 
+ 
+  bool GuaranteedToExecute = 
+      SafetyInfo->isGuaranteedToExecute(Inst, DT, CurLoop); 
+ 
+  if (!GuaranteedToExecute) { 
+    auto *LI = dyn_cast<LoadInst>(&Inst); 
+    if (LI && CurLoop->isLoopInvariant(LI->getPointerOperand())) 
+      ORE->emit([&]() { 
+        return OptimizationRemarkMissed( 
+                   DEBUG_TYPE, "LoadWithLoopInvariantAddressCondExecuted", LI) 
+               << "failed to hoist load with loop-invariant address " 
+                  "because load is conditionally executed"; 
+      }); 
+  } 
+ 
+  return GuaranteedToExecute; 
+} 
+ 
+namespace { 
+class LoopPromoter : public LoadAndStorePromoter { 
+  Value *SomePtr; // Designated pointer to store to. 
+  const SmallSetVector<Value *, 8> &PointerMustAliases; 
+  SmallVectorImpl<BasicBlock *> &LoopExitBlocks; 
+  SmallVectorImpl<Instruction *> &LoopInsertPts; 
+  SmallVectorImpl<MemoryAccess *> &MSSAInsertPts; 
+  PredIteratorCache &PredCache; 
   AliasSetTracker *AST;
-  MemorySSAUpdater *MSSAU;
-  LoopInfo &LI;
-  DebugLoc DL;
-  int Alignment;
-  bool UnorderedAtomic;
-  AAMDNodes AATags;
-  ICFLoopSafetyInfo &SafetyInfo;
-
-  Value *maybeInsertLCSSAPHI(Value *V, BasicBlock *BB) const {
-    if (Instruction *I = dyn_cast<Instruction>(V))
-      if (Loop *L = LI.getLoopFor(I->getParent()))
-        if (!L->contains(BB)) {
-          // We need to create an LCSSA PHI node for the incoming value and
-          // store that.
-          PHINode *PN = PHINode::Create(I->getType(), PredCache.size(BB),
-                                        I->getName() + ".lcssa", &BB->front());
-          for (BasicBlock *Pred : PredCache.get(BB))
-            PN->addIncoming(I, Pred);
-          return PN;
-        }
-    return V;
-  }
-
-public:
-  LoopPromoter(Value *SP, ArrayRef<const Instruction *> Insts, SSAUpdater &S,
-               const SmallSetVector<Value *, 8> &PMA,
-               SmallVectorImpl<BasicBlock *> &LEB,
-               SmallVectorImpl<Instruction *> &LIP,
-               SmallVectorImpl<MemoryAccess *> &MSSAIP, PredIteratorCache &PIC,
+  MemorySSAUpdater *MSSAU; 
+  LoopInfo &LI; 
+  DebugLoc DL; 
+  int Alignment; 
+  bool UnorderedAtomic; 
+  AAMDNodes AATags; 
+  ICFLoopSafetyInfo &SafetyInfo; 
+ 
+  Value *maybeInsertLCSSAPHI(Value *V, BasicBlock *BB) const { 
+    if (Instruction *I = dyn_cast<Instruction>(V)) 
+      if (Loop *L = LI.getLoopFor(I->getParent())) 
+        if (!L->contains(BB)) { 
+          // We need to create an LCSSA PHI node for the incoming value and 
+          // store that. 
+          PHINode *PN = PHINode::Create(I->getType(), PredCache.size(BB), 
+                                        I->getName() + ".lcssa", &BB->front()); 
+          for (BasicBlock *Pred : PredCache.get(BB)) 
+            PN->addIncoming(I, Pred); 
+          return PN; 
+        } 
+    return V; 
+  } 
+ 
+public: 
+  LoopPromoter(Value *SP, ArrayRef<const Instruction *> Insts, SSAUpdater &S, 
+               const SmallSetVector<Value *, 8> &PMA, 
+               SmallVectorImpl<BasicBlock *> &LEB, 
+               SmallVectorImpl<Instruction *> &LIP, 
+               SmallVectorImpl<MemoryAccess *> &MSSAIP, PredIteratorCache &PIC, 
                AliasSetTracker *ast, MemorySSAUpdater *MSSAU, LoopInfo &li,
-               DebugLoc dl, int alignment, bool UnorderedAtomic,
-               const AAMDNodes &AATags, ICFLoopSafetyInfo &SafetyInfo)
-      : LoadAndStorePromoter(Insts, S), SomePtr(SP), PointerMustAliases(PMA),
-        LoopExitBlocks(LEB), LoopInsertPts(LIP), MSSAInsertPts(MSSAIP),
-        PredCache(PIC), AST(ast), MSSAU(MSSAU), LI(li), DL(std::move(dl)),
-        Alignment(alignment), UnorderedAtomic(UnorderedAtomic), AATags(AATags),
-        SafetyInfo(SafetyInfo) {}
-
-  bool isInstInList(Instruction *I,
-                    const SmallVectorImpl<Instruction *> &) const override {
-    Value *Ptr;
-    if (LoadInst *LI = dyn_cast<LoadInst>(I))
-      Ptr = LI->getOperand(0);
-    else
-      Ptr = cast<StoreInst>(I)->getPointerOperand();
-    return PointerMustAliases.count(Ptr);
-  }
-
-  void doExtraRewritesBeforeFinalDeletion() override {
-    // Insert stores after in the loop exit blocks.  Each exit block gets a
-    // store of the live-out values that feed them.  Since we've already told
-    // the SSA updater about the defs in the loop and the preheader
-    // definition, it is all set and we can start using it.
-    for (unsigned i = 0, e = LoopExitBlocks.size(); i != e; ++i) {
-      BasicBlock *ExitBlock = LoopExitBlocks[i];
-      Value *LiveInValue = SSA.GetValueInMiddleOfBlock(ExitBlock);
-      LiveInValue = maybeInsertLCSSAPHI(LiveInValue, ExitBlock);
-      Value *Ptr = maybeInsertLCSSAPHI(SomePtr, ExitBlock);
-      Instruction *InsertPos = LoopInsertPts[i];
-      StoreInst *NewSI = new StoreInst(LiveInValue, Ptr, InsertPos);
-      if (UnorderedAtomic)
-        NewSI->setOrdering(AtomicOrdering::Unordered);
-      NewSI->setAlignment(Align(Alignment));
-      NewSI->setDebugLoc(DL);
-      if (AATags)
-        NewSI->setAAMetadata(AATags);
-
-      if (MSSAU) {
-        MemoryAccess *MSSAInsertPoint = MSSAInsertPts[i];
-        MemoryAccess *NewMemAcc;
-        if (!MSSAInsertPoint) {
-          NewMemAcc = MSSAU->createMemoryAccessInBB(
-              NewSI, nullptr, NewSI->getParent(), MemorySSA::Beginning);
-        } else {
-          NewMemAcc =
-              MSSAU->createMemoryAccessAfter(NewSI, nullptr, MSSAInsertPoint);
-        }
-        MSSAInsertPts[i] = NewMemAcc;
-        MSSAU->insertDef(cast<MemoryDef>(NewMemAcc), true);
-        // FIXME: true for safety, false may still be correct.
-      }
-    }
-  }
-
-  void replaceLoadWithValue(LoadInst *LI, Value *V) const override {
-    // Update alias analysis.
+               DebugLoc dl, int alignment, bool UnorderedAtomic, 
+               const AAMDNodes &AATags, ICFLoopSafetyInfo &SafetyInfo) 
+      : LoadAndStorePromoter(Insts, S), SomePtr(SP), PointerMustAliases(PMA), 
+        LoopExitBlocks(LEB), LoopInsertPts(LIP), MSSAInsertPts(MSSAIP), 
+        PredCache(PIC), AST(ast), MSSAU(MSSAU), LI(li), DL(std::move(dl)), 
+        Alignment(alignment), UnorderedAtomic(UnorderedAtomic), AATags(AATags), 
+        SafetyInfo(SafetyInfo) {} 
+ 
+  bool isInstInList(Instruction *I, 
+                    const SmallVectorImpl<Instruction *> &) const override { 
+    Value *Ptr; 
+    if (LoadInst *LI = dyn_cast<LoadInst>(I)) 
+      Ptr = LI->getOperand(0); 
+    else 
+      Ptr = cast<StoreInst>(I)->getPointerOperand(); 
+    return PointerMustAliases.count(Ptr); 
+  } 
+ 
+  void doExtraRewritesBeforeFinalDeletion() override { 
+    // Insert stores after in the loop exit blocks.  Each exit block gets a 
+    // store of the live-out values that feed them.  Since we've already told 
+    // the SSA updater about the defs in the loop and the preheader 
+    // definition, it is all set and we can start using it. 
+    for (unsigned i = 0, e = LoopExitBlocks.size(); i != e; ++i) { 
+      BasicBlock *ExitBlock = LoopExitBlocks[i]; 
+      Value *LiveInValue = SSA.GetValueInMiddleOfBlock(ExitBlock); 
+      LiveInValue = maybeInsertLCSSAPHI(LiveInValue, ExitBlock); 
+      Value *Ptr = maybeInsertLCSSAPHI(SomePtr, ExitBlock); 
+      Instruction *InsertPos = LoopInsertPts[i]; 
+      StoreInst *NewSI = new StoreInst(LiveInValue, Ptr, InsertPos); 
+      if (UnorderedAtomic) 
+        NewSI->setOrdering(AtomicOrdering::Unordered); 
+      NewSI->setAlignment(Align(Alignment)); 
+      NewSI->setDebugLoc(DL); 
+      if (AATags) 
+        NewSI->setAAMetadata(AATags); 
+ 
+      if (MSSAU) { 
+        MemoryAccess *MSSAInsertPoint = MSSAInsertPts[i]; 
+        MemoryAccess *NewMemAcc; 
+        if (!MSSAInsertPoint) { 
+          NewMemAcc = MSSAU->createMemoryAccessInBB( 
+              NewSI, nullptr, NewSI->getParent(), MemorySSA::Beginning); 
+        } else { 
+          NewMemAcc = 
+              MSSAU->createMemoryAccessAfter(NewSI, nullptr, MSSAInsertPoint); 
+        } 
+        MSSAInsertPts[i] = NewMemAcc; 
+        MSSAU->insertDef(cast<MemoryDef>(NewMemAcc), true); 
+        // FIXME: true for safety, false may still be correct. 
+      } 
+    } 
+  } 
+ 
+  void replaceLoadWithValue(LoadInst *LI, Value *V) const override { 
+    // Update alias analysis. 
     if (AST)
       AST->copyValue(LI, V);
-  }
-  void instructionDeleted(Instruction *I) const override {
-    SafetyInfo.removeInstruction(I);
+  } 
+  void instructionDeleted(Instruction *I) const override { 
+    SafetyInfo.removeInstruction(I); 
     if (AST)
       AST->deleteValue(I);
-    if (MSSAU)
-      MSSAU->removeMemoryAccess(I);
-  }
-};
-
-
-/// Return true iff we can prove that a caller of this function can not inspect
-/// the contents of the provided object in a well defined program.
-bool isKnownNonEscaping(Value *Object, const TargetLibraryInfo *TLI) {
-  if (isa<AllocaInst>(Object))
-    // Since the alloca goes out of scope, we know the caller can't retain a
-    // reference to it and be well defined.  Thus, we don't need to check for
-    // capture.
-    return true;
-
-  // For all other objects we need to know that the caller can't possibly
-  // have gotten a reference to the object.  There are two components of
-  // that:
-  //   1) Object can't be escaped by this function.  This is what
-  //      PointerMayBeCaptured checks.
-  //   2) Object can't have been captured at definition site.  For this, we
-  //      need to know the return value is noalias.  At the moment, we use a
-  //      weaker condition and handle only AllocLikeFunctions (which are
-  //      known to be noalias).  TODO
-  return isAllocLikeFn(Object, TLI) &&
-    !PointerMayBeCaptured(Object, true, true);
-}
-
-} // namespace
-
-/// Try to promote memory values to scalars by sinking stores out of the
-/// loop and moving loads to before the loop.  We do this by looping over
-/// the stores in the loop, looking for stores to Must pointers which are
-/// loop invariant.
-///
-bool llvm::promoteLoopAccessesToScalars(
-    const SmallSetVector<Value *, 8> &PointerMustAliases,
-    SmallVectorImpl<BasicBlock *> &ExitBlocks,
-    SmallVectorImpl<Instruction *> &InsertPts,
-    SmallVectorImpl<MemoryAccess *> &MSSAInsertPts, PredIteratorCache &PIC,
-    LoopInfo *LI, DominatorTree *DT, const TargetLibraryInfo *TLI,
-    Loop *CurLoop, AliasSetTracker *CurAST, MemorySSAUpdater *MSSAU,
-    ICFLoopSafetyInfo *SafetyInfo, OptimizationRemarkEmitter *ORE) {
-  // Verify inputs.
-  assert(LI != nullptr && DT != nullptr && CurLoop != nullptr &&
+    if (MSSAU) 
+      MSSAU->removeMemoryAccess(I); 
+  } 
+}; 
+ 
+ 
+/// Return true iff we can prove that a caller of this function can not inspect 
+/// the contents of the provided object in a well defined program. 
+bool isKnownNonEscaping(Value *Object, const TargetLibraryInfo *TLI) { 
+  if (isa<AllocaInst>(Object)) 
+    // Since the alloca goes out of scope, we know the caller can't retain a 
+    // reference to it and be well defined.  Thus, we don't need to check for 
+    // capture. 
+    return true; 
+ 
+  // For all other objects we need to know that the caller can't possibly 
+  // have gotten a reference to the object.  There are two components of 
+  // that: 
+  //   1) Object can't be escaped by this function.  This is what 
+  //      PointerMayBeCaptured checks. 
+  //   2) Object can't have been captured at definition site.  For this, we 
+  //      need to know the return value is noalias.  At the moment, we use a 
+  //      weaker condition and handle only AllocLikeFunctions (which are 
+  //      known to be noalias).  TODO 
+  return isAllocLikeFn(Object, TLI) && 
+    !PointerMayBeCaptured(Object, true, true); 
+} 
+ 
+} // namespace 
+ 
+/// Try to promote memory values to scalars by sinking stores out of the 
+/// loop and moving loads to before the loop.  We do this by looping over 
+/// the stores in the loop, looking for stores to Must pointers which are 
+/// loop invariant. 
+/// 
+bool llvm::promoteLoopAccessesToScalars( 
+    const SmallSetVector<Value *, 8> &PointerMustAliases, 
+    SmallVectorImpl<BasicBlock *> &ExitBlocks, 
+    SmallVectorImpl<Instruction *> &InsertPts, 
+    SmallVectorImpl<MemoryAccess *> &MSSAInsertPts, PredIteratorCache &PIC, 
+    LoopInfo *LI, DominatorTree *DT, const TargetLibraryInfo *TLI, 
+    Loop *CurLoop, AliasSetTracker *CurAST, MemorySSAUpdater *MSSAU, 
+    ICFLoopSafetyInfo *SafetyInfo, OptimizationRemarkEmitter *ORE) { 
+  // Verify inputs. 
+  assert(LI != nullptr && DT != nullptr && CurLoop != nullptr && 
          SafetyInfo != nullptr &&
-         "Unexpected Input to promoteLoopAccessesToScalars");
-
-  Value *SomePtr = *PointerMustAliases.begin();
-  BasicBlock *Preheader = CurLoop->getLoopPreheader();
-
-  // It is not safe to promote a load/store from the loop if the load/store is
-  // conditional.  For example, turning:
-  //
-  //    for () { if (c) *P += 1; }
-  //
-  // into:
-  //
-  //    tmp = *P;  for () { if (c) tmp +=1; } *P = tmp;
-  //
-  // is not safe, because *P may only be valid to access if 'c' is true.
-  //
-  // The safety property divides into two parts:
-  // p1) The memory may not be dereferenceable on entry to the loop.  In this
-  //    case, we can't insert the required load in the preheader.
-  // p2) The memory model does not allow us to insert a store along any dynamic
-  //    path which did not originally have one.
-  //
-  // If at least one store is guaranteed to execute, both properties are
-  // satisfied, and promotion is legal.
-  //
-  // This, however, is not a necessary condition. Even if no store/load is
-  // guaranteed to execute, we can still establish these properties.
-  // We can establish (p1) by proving that hoisting the load into the preheader
-  // is safe (i.e. proving dereferenceability on all paths through the loop). We
-  // can use any access within the alias set to prove dereferenceability,
-  // since they're all must alias.
-  //
-  // There are two ways establish (p2):
-  // a) Prove the location is thread-local. In this case the memory model
-  // requirement does not apply, and stores are safe to insert.
-  // b) Prove a store dominates every exit block. In this case, if an exit
-  // blocks is reached, the original dynamic path would have taken us through
-  // the store, so inserting a store into the exit block is safe. Note that this
-  // is different from the store being guaranteed to execute. For instance,
-  // if an exception is thrown on the first iteration of the loop, the original
-  // store is never executed, but the exit blocks are not executed either.
-
-  bool DereferenceableInPH = false;
-  bool SafeToInsertStore = false;
-
-  SmallVector<Instruction *, 64> LoopUses;
-
-  // We start with an alignment of one and try to find instructions that allow
-  // us to prove better alignment.
-  Align Alignment;
-  // Keep track of which types of access we see
-  bool SawUnorderedAtomic = false;
-  bool SawNotAtomic = false;
-  AAMDNodes AATags;
-
-  const DataLayout &MDL = Preheader->getModule()->getDataLayout();
-
-  bool IsKnownThreadLocalObject = false;
-  if (SafetyInfo->anyBlockMayThrow()) {
-    // If a loop can throw, we have to insert a store along each unwind edge.
-    // That said, we can't actually make the unwind edge explicit. Therefore,
-    // we have to prove that the store is dead along the unwind edge.  We do
-    // this by proving that the caller can't have a reference to the object
-    // after return and thus can't possibly load from the object.
+         "Unexpected Input to promoteLoopAccessesToScalars"); 
+ 
+  Value *SomePtr = *PointerMustAliases.begin(); 
+  BasicBlock *Preheader = CurLoop->getLoopPreheader(); 
+ 
+  // It is not safe to promote a load/store from the loop if the load/store is 
+  // conditional.  For example, turning: 
+  // 
+  //    for () { if (c) *P += 1; } 
+  // 
+  // into: 
+  // 
+  //    tmp = *P;  for () { if (c) tmp +=1; } *P = tmp; 
+  // 
+  // is not safe, because *P may only be valid to access if 'c' is true. 
+  // 
+  // The safety property divides into two parts: 
+  // p1) The memory may not be dereferenceable on entry to the loop.  In this 
+  //    case, we can't insert the required load in the preheader. 
+  // p2) The memory model does not allow us to insert a store along any dynamic 
+  //    path which did not originally have one. 
+  // 
+  // If at least one store is guaranteed to execute, both properties are 
+  // satisfied, and promotion is legal. 
+  // 
+  // This, however, is not a necessary condition. Even if no store/load is 
+  // guaranteed to execute, we can still establish these properties. 
+  // We can establish (p1) by proving that hoisting the load into the preheader 
+  // is safe (i.e. proving dereferenceability on all paths through the loop). We 
+  // can use any access within the alias set to prove dereferenceability, 
+  // since they're all must alias. 
+  // 
+  // There are two ways establish (p2): 
+  // a) Prove the location is thread-local. In this case the memory model 
+  // requirement does not apply, and stores are safe to insert. 
+  // b) Prove a store dominates every exit block. In this case, if an exit 
+  // blocks is reached, the original dynamic path would have taken us through 
+  // the store, so inserting a store into the exit block is safe. Note that this 
+  // is different from the store being guaranteed to execute. For instance, 
+  // if an exception is thrown on the first iteration of the loop, the original 
+  // store is never executed, but the exit blocks are not executed either. 
+ 
+  bool DereferenceableInPH = false; 
+  bool SafeToInsertStore = false; 
+ 
+  SmallVector<Instruction *, 64> LoopUses; 
+ 
+  // We start with an alignment of one and try to find instructions that allow 
+  // us to prove better alignment. 
+  Align Alignment; 
+  // Keep track of which types of access we see 
+  bool SawUnorderedAtomic = false; 
+  bool SawNotAtomic = false; 
+  AAMDNodes AATags; 
+ 
+  const DataLayout &MDL = Preheader->getModule()->getDataLayout(); 
+ 
+  bool IsKnownThreadLocalObject = false; 
+  if (SafetyInfo->anyBlockMayThrow()) { 
+    // If a loop can throw, we have to insert a store along each unwind edge. 
+    // That said, we can't actually make the unwind edge explicit. Therefore, 
+    // we have to prove that the store is dead along the unwind edge.  We do 
+    // this by proving that the caller can't have a reference to the object 
+    // after return and thus can't possibly load from the object. 
     Value *Object = getUnderlyingObject(SomePtr);
-    if (!isKnownNonEscaping(Object, TLI))
-      return false;
-    // Subtlety: Alloca's aren't visible to callers, but *are* potentially
-    // visible to other threads if captured and used during their lifetimes.
-    IsKnownThreadLocalObject = !isa<AllocaInst>(Object);
-  }
-
-  // Check that all of the pointers in the alias set have the same type.  We
-  // cannot (yet) promote a memory location that is loaded and stored in
-  // different sizes.  While we are at it, collect alignment and AA info.
-  for (Value *ASIV : PointerMustAliases) {
-    // Check that all of the pointers in the alias set have the same type.  We
-    // cannot (yet) promote a memory location that is loaded and stored in
-    // different sizes.
-    if (SomePtr->getType() != ASIV->getType())
-      return false;
-
-    for (User *U : ASIV->users()) {
-      // Ignore instructions that are outside the loop.
-      Instruction *UI = dyn_cast<Instruction>(U);
-      if (!UI || !CurLoop->contains(UI))
-        continue;
-
-      // If there is an non-load/store instruction in the loop, we can't promote
-      // it.
-      if (LoadInst *Load = dyn_cast<LoadInst>(UI)) {
-        if (!Load->isUnordered())
-          return false;
-
-        SawUnorderedAtomic |= Load->isAtomic();
-        SawNotAtomic |= !Load->isAtomic();
-
-        Align InstAlignment = Load->getAlign();
-
-        // Note that proving a load safe to speculate requires proving
-        // sufficient alignment at the target location.  Proving it guaranteed
-        // to execute does as well.  Thus we can increase our guaranteed
-        // alignment as well. 
-        if (!DereferenceableInPH || (InstAlignment > Alignment))
-          if (isSafeToExecuteUnconditionally(*Load, DT, CurLoop, SafetyInfo,
-                                             ORE, Preheader->getTerminator())) {
-            DereferenceableInPH = true;
-            Alignment = std::max(Alignment, InstAlignment);
-          }
-      } else if (const StoreInst *Store = dyn_cast<StoreInst>(UI)) {
-        // Stores *of* the pointer are not interesting, only stores *to* the
-        // pointer.
-        if (UI->getOperand(1) != ASIV)
-          continue;
-        if (!Store->isUnordered())
-          return false;
-
-        SawUnorderedAtomic |= Store->isAtomic();
-        SawNotAtomic |= !Store->isAtomic();
-
-        // If the store is guaranteed to execute, both properties are satisfied.
-        // We may want to check if a store is guaranteed to execute even if we
-        // already know that promotion is safe, since it may have higher
-        // alignment than any other guaranteed stores, in which case we can
-        // raise the alignment on the promoted store.
-        Align InstAlignment = Store->getAlign();
-
-        if (!DereferenceableInPH || !SafeToInsertStore ||
-            (InstAlignment > Alignment)) {
-          if (SafetyInfo->isGuaranteedToExecute(*UI, DT, CurLoop)) {
-            DereferenceableInPH = true;
-            SafeToInsertStore = true;
-            Alignment = std::max(Alignment, InstAlignment);
-          }
-        }
-
-        // If a store dominates all exit blocks, it is safe to sink.
-        // As explained above, if an exit block was executed, a dominating
-        // store must have been executed at least once, so we are not
-        // introducing stores on paths that did not have them.
-        // Note that this only looks at explicit exit blocks. If we ever
-        // start sinking stores into unwind edges (see above), this will break.
-        if (!SafeToInsertStore)
-          SafeToInsertStore = llvm::all_of(ExitBlocks, [&](BasicBlock *Exit) {
-            return DT->dominates(Store->getParent(), Exit);
-          });
-
-        // If the store is not guaranteed to execute, we may still get
-        // deref info through it.
-        if (!DereferenceableInPH) {
-          DereferenceableInPH = isDereferenceableAndAlignedPointer(
-              Store->getPointerOperand(), Store->getValueOperand()->getType(),
-              Store->getAlign(), MDL, Preheader->getTerminator(), DT);
-        }
-      } else
-        return false; // Not a load or store.
-
-      // Merge the AA tags.
-      if (LoopUses.empty()) {
-        // On the first load/store, just take its AA tags.
-        UI->getAAMetadata(AATags);
-      } else if (AATags) {
-        UI->getAAMetadata(AATags, /* Merge = */ true);
-      }
-
-      LoopUses.push_back(UI);
-    }
-  }
-
-  // If we found both an unordered atomic instruction and a non-atomic memory
-  // access, bail.  We can't blindly promote non-atomic to atomic since we
-  // might not be able to lower the result.  We can't downgrade since that
-  // would violate memory model.  Also, align 0 is an error for atomics.
-  if (SawUnorderedAtomic && SawNotAtomic)
-    return false;
-
-  // If we're inserting an atomic load in the preheader, we must be able to
-  // lower it.  We're only guaranteed to be able to lower naturally aligned
-  // atomics.
-  auto *SomePtrElemType = SomePtr->getType()->getPointerElementType();
-  if (SawUnorderedAtomic &&
-      Alignment < MDL.getTypeStoreSize(SomePtrElemType))
-    return false;
-
-  // If we couldn't prove we can hoist the load, bail.
-  if (!DereferenceableInPH)
-    return false;
-
-  // We know we can hoist the load, but don't have a guaranteed store.
-  // Check whether the location is thread-local. If it is, then we can insert
-  // stores along paths which originally didn't have them without violating the
-  // memory model.
-  if (!SafeToInsertStore) {
-    if (IsKnownThreadLocalObject)
-      SafeToInsertStore = true;
-    else {
+    if (!isKnownNonEscaping(Object, TLI)) 
+      return false; 
+    // Subtlety: Alloca's aren't visible to callers, but *are* potentially 
+    // visible to other threads if captured and used during their lifetimes. 
+    IsKnownThreadLocalObject = !isa<AllocaInst>(Object); 
+  } 
+ 
+  // Check that all of the pointers in the alias set have the same type.  We 
+  // cannot (yet) promote a memory location that is loaded and stored in 
+  // different sizes.  While we are at it, collect alignment and AA info. 
+  for (Value *ASIV : PointerMustAliases) { 
+    // Check that all of the pointers in the alias set have the same type.  We 
+    // cannot (yet) promote a memory location that is loaded and stored in 
+    // different sizes. 
+    if (SomePtr->getType() != ASIV->getType()) 
+      return false; 
+ 
+    for (User *U : ASIV->users()) { 
+      // Ignore instructions that are outside the loop. 
+      Instruction *UI = dyn_cast<Instruction>(U); 
+      if (!UI || !CurLoop->contains(UI)) 
+        continue; 
+ 
+      // If there is an non-load/store instruction in the loop, we can't promote 
+      // it. 
+      if (LoadInst *Load = dyn_cast<LoadInst>(UI)) { 
+        if (!Load->isUnordered()) 
+          return false; 
+ 
+        SawUnorderedAtomic |= Load->isAtomic(); 
+        SawNotAtomic |= !Load->isAtomic(); 
+ 
+        Align InstAlignment = Load->getAlign(); 
+ 
+        // Note that proving a load safe to speculate requires proving 
+        // sufficient alignment at the target location.  Proving it guaranteed 
+        // to execute does as well.  Thus we can increase our guaranteed 
+        // alignment as well.  
+        if (!DereferenceableInPH || (InstAlignment > Alignment)) 
+          if (isSafeToExecuteUnconditionally(*Load, DT, CurLoop, SafetyInfo, 
+                                             ORE, Preheader->getTerminator())) { 
+            DereferenceableInPH = true; 
+            Alignment = std::max(Alignment, InstAlignment); 
+          } 
+      } else if (const StoreInst *Store = dyn_cast<StoreInst>(UI)) { 
+        // Stores *of* the pointer are not interesting, only stores *to* the 
+        // pointer. 
+        if (UI->getOperand(1) != ASIV) 
+          continue; 
+        if (!Store->isUnordered()) 
+          return false; 
+ 
+        SawUnorderedAtomic |= Store->isAtomic(); 
+        SawNotAtomic |= !Store->isAtomic(); 
+ 
+        // If the store is guaranteed to execute, both properties are satisfied. 
+        // We may want to check if a store is guaranteed to execute even if we 
+        // already know that promotion is safe, since it may have higher 
+        // alignment than any other guaranteed stores, in which case we can 
+        // raise the alignment on the promoted store. 
+        Align InstAlignment = Store->getAlign(); 
+ 
+        if (!DereferenceableInPH || !SafeToInsertStore || 
+            (InstAlignment > Alignment)) { 
+          if (SafetyInfo->isGuaranteedToExecute(*UI, DT, CurLoop)) { 
+            DereferenceableInPH = true; 
+            SafeToInsertStore = true; 
+            Alignment = std::max(Alignment, InstAlignment); 
+          } 
+        } 
+ 
+        // If a store dominates all exit blocks, it is safe to sink. 
+        // As explained above, if an exit block was executed, a dominating 
+        // store must have been executed at least once, so we are not 
+        // introducing stores on paths that did not have them. 
+        // Note that this only looks at explicit exit blocks. If we ever 
+        // start sinking stores into unwind edges (see above), this will break. 
+        if (!SafeToInsertStore) 
+          SafeToInsertStore = llvm::all_of(ExitBlocks, [&](BasicBlock *Exit) { 
+            return DT->dominates(Store->getParent(), Exit); 
+          }); 
+ 
+        // If the store is not guaranteed to execute, we may still get 
+        // deref info through it. 
+        if (!DereferenceableInPH) { 
+          DereferenceableInPH = isDereferenceableAndAlignedPointer( 
+              Store->getPointerOperand(), Store->getValueOperand()->getType(), 
+              Store->getAlign(), MDL, Preheader->getTerminator(), DT); 
+        } 
+      } else 
+        return false; // Not a load or store. 
+ 
+      // Merge the AA tags. 
+      if (LoopUses.empty()) { 
+        // On the first load/store, just take its AA tags. 
+        UI->getAAMetadata(AATags); 
+      } else if (AATags) { 
+        UI->getAAMetadata(AATags, /* Merge = */ true); 
+      } 
+ 
+      LoopUses.push_back(UI); 
+    } 
+  } 
+ 
+  // If we found both an unordered atomic instruction and a non-atomic memory 
+  // access, bail.  We can't blindly promote non-atomic to atomic since we 
+  // might not be able to lower the result.  We can't downgrade since that 
+  // would violate memory model.  Also, align 0 is an error for atomics. 
+  if (SawUnorderedAtomic && SawNotAtomic) 
+    return false; 
+ 
+  // If we're inserting an atomic load in the preheader, we must be able to 
+  // lower it.  We're only guaranteed to be able to lower naturally aligned 
+  // atomics. 
+  auto *SomePtrElemType = SomePtr->getType()->getPointerElementType(); 
+  if (SawUnorderedAtomic && 
+      Alignment < MDL.getTypeStoreSize(SomePtrElemType)) 
+    return false; 
+ 
+  // If we couldn't prove we can hoist the load, bail. 
+  if (!DereferenceableInPH) 
+    return false; 
+ 
+  // We know we can hoist the load, but don't have a guaranteed store. 
+  // Check whether the location is thread-local. If it is, then we can insert 
+  // stores along paths which originally didn't have them without violating the 
+  // memory model. 
+  if (!SafeToInsertStore) { 
+    if (IsKnownThreadLocalObject) 
+      SafeToInsertStore = true; 
+    else { 
       Value *Object = getUnderlyingObject(SomePtr);
-      SafeToInsertStore =
-          (isAllocLikeFn(Object, TLI) || isa<AllocaInst>(Object)) &&
-          !PointerMayBeCaptured(Object, true, true);
-    }
-  }
-
-  // If we've still failed to prove we can sink the store, give up.
-  if (!SafeToInsertStore)
-    return false;
-
-  // Otherwise, this is safe to promote, lets do it!
-  LLVM_DEBUG(dbgs() << "LICM: Promoting value stored to in loop: " << *SomePtr
-                    << '\n');
-  ORE->emit([&]() {
-    return OptimizationRemark(DEBUG_TYPE, "PromoteLoopAccessesToScalar",
-                              LoopUses[0])
-           << "Moving accesses to memory location out of the loop";
-  });
-  ++NumPromoted;
-
-  // Look at all the loop uses, and try to merge their locations.
-  std::vector<const DILocation *> LoopUsesLocs;
-  for (auto U : LoopUses)
-    LoopUsesLocs.push_back(U->getDebugLoc().get());
-  auto DL = DebugLoc(DILocation::getMergedLocations(LoopUsesLocs));
-
-  // We use the SSAUpdater interface to insert phi nodes as required.
-  SmallVector<PHINode *, 16> NewPHIs;
-  SSAUpdater SSA(&NewPHIs);
-  LoopPromoter Promoter(SomePtr, LoopUses, SSA, PointerMustAliases, ExitBlocks,
+      SafeToInsertStore = 
+          (isAllocLikeFn(Object, TLI) || isa<AllocaInst>(Object)) && 
+          !PointerMayBeCaptured(Object, true, true); 
+    } 
+  } 
+ 
+  // If we've still failed to prove we can sink the store, give up. 
+  if (!SafeToInsertStore) 
+    return false; 
+ 
+  // Otherwise, this is safe to promote, lets do it! 
+  LLVM_DEBUG(dbgs() << "LICM: Promoting value stored to in loop: " << *SomePtr 
+                    << '\n'); 
+  ORE->emit([&]() { 
+    return OptimizationRemark(DEBUG_TYPE, "PromoteLoopAccessesToScalar", 
+                              LoopUses[0]) 
+           << "Moving accesses to memory location out of the loop"; 
+  }); 
+  ++NumPromoted; 
+ 
+  // Look at all the loop uses, and try to merge their locations. 
+  std::vector<const DILocation *> LoopUsesLocs; 
+  for (auto U : LoopUses) 
+    LoopUsesLocs.push_back(U->getDebugLoc().get()); 
+  auto DL = DebugLoc(DILocation::getMergedLocations(LoopUsesLocs)); 
+ 
+  // We use the SSAUpdater interface to insert phi nodes as required. 
+  SmallVector<PHINode *, 16> NewPHIs; 
+  SSAUpdater SSA(&NewPHIs); 
+  LoopPromoter Promoter(SomePtr, LoopUses, SSA, PointerMustAliases, ExitBlocks, 
                         InsertPts, MSSAInsertPts, PIC, CurAST, MSSAU, *LI, DL,
-                        Alignment.value(), SawUnorderedAtomic, AATags,
-                        *SafetyInfo);
-
-  // Set up the preheader to have a definition of the value.  It is the live-out
-  // value from the preheader that uses in the loop will use.
-  LoadInst *PreheaderLoad = new LoadInst(
-      SomePtr->getType()->getPointerElementType(), SomePtr,
-      SomePtr->getName() + ".promoted", Preheader->getTerminator());
-  if (SawUnorderedAtomic)
-    PreheaderLoad->setOrdering(AtomicOrdering::Unordered);
-  PreheaderLoad->setAlignment(Alignment);
-  PreheaderLoad->setDebugLoc(DebugLoc());
-  if (AATags)
-    PreheaderLoad->setAAMetadata(AATags);
-  SSA.AddAvailableValue(Preheader, PreheaderLoad);
-
-  if (MSSAU) {
-    MemoryAccess *PreheaderLoadMemoryAccess = MSSAU->createMemoryAccessInBB(
-        PreheaderLoad, nullptr, PreheaderLoad->getParent(), MemorySSA::End);
-    MemoryUse *NewMemUse = cast<MemoryUse>(PreheaderLoadMemoryAccess);
-    MSSAU->insertUse(NewMemUse, /*RenameUses=*/true);
-  }
-
-  if (MSSAU && VerifyMemorySSA)
-    MSSAU->getMemorySSA()->verifyMemorySSA();
-  // Rewrite all the loads in the loop and remember all the definitions from
-  // stores in the loop.
-  Promoter.run(LoopUses);
-
-  if (MSSAU && VerifyMemorySSA)
-    MSSAU->getMemorySSA()->verifyMemorySSA();
-  // If the SSAUpdater didn't use the load in the preheader, just zap it now.
-  if (PreheaderLoad->use_empty())
-    eraseInstruction(*PreheaderLoad, *SafetyInfo, CurAST, MSSAU);
-
-  return true;
-}
-
-/// Returns an owning pointer to an alias set which incorporates aliasing info
-/// from L and all subloops of L.
-std::unique_ptr<AliasSetTracker>
-LoopInvariantCodeMotion::collectAliasInfoForLoop(Loop *L, LoopInfo *LI,
-                                                 AAResults *AA) {
-  auto CurAST = std::make_unique<AliasSetTracker>(*AA);
-
-  // Add everything from all the sub loops.
-  for (Loop *InnerL : L->getSubLoops())
-    for (BasicBlock *BB : InnerL->blocks())
-      CurAST->add(*BB);
-
-  // And merge in this loop (without anything from inner loops).
-  for (BasicBlock *BB : L->blocks())
-    if (LI->getLoopFor(BB) == L)
-      CurAST->add(*BB);
-
-  return CurAST;
-}
-
-std::unique_ptr<AliasSetTracker>
-LoopInvariantCodeMotion::collectAliasInfoForLoopWithMSSA(
-    Loop *L, AAResults *AA, MemorySSAUpdater *MSSAU) {
-  auto *MSSA = MSSAU->getMemorySSA();
-  auto CurAST = std::make_unique<AliasSetTracker>(*AA, MSSA, L);
-  CurAST->addAllInstructionsInLoopUsingMSSA();
-  return CurAST;
-}
-
-static bool pointerInvalidatedByLoop(MemoryLocation MemLoc,
-                                     AliasSetTracker *CurAST, Loop *CurLoop,
-                                     AAResults *AA) {
-  // First check to see if any of the basic blocks in CurLoop invalidate *V.
-  bool isInvalidatedAccordingToAST = CurAST->getAliasSetFor(MemLoc).isMod();
-
-  if (!isInvalidatedAccordingToAST || !LICMN2Theshold)
-    return isInvalidatedAccordingToAST;
-
-  // Check with a diagnostic analysis if we can refine the information above.
-  // This is to identify the limitations of using the AST.
-  // The alias set mechanism used by LICM has a major weakness in that it
-  // combines all things which may alias into a single set *before* asking
-  // modref questions. As a result, a single readonly call within a loop will
-  // collapse all loads and stores into a single alias set and report
-  // invalidation if the loop contains any store. For example, readonly calls
-  // with deopt states have this form and create a general alias set with all
-  // loads and stores.  In order to get any LICM in loops containing possible
-  // deopt states we need a more precise invalidation of checking the mod ref
-  // info of each instruction within the loop and LI. This has a complexity of
-  // O(N^2), so currently, it is used only as a diagnostic tool since the
-  // default value of LICMN2Threshold is zero.
-
-  // Don't look at nested loops.
-  if (CurLoop->begin() != CurLoop->end())
-    return true;
-
-  int N = 0;
-  for (BasicBlock *BB : CurLoop->getBlocks())
-    for (Instruction &I : *BB) {
-      if (N >= LICMN2Theshold) {
-        LLVM_DEBUG(dbgs() << "Alasing N2 threshold exhausted for "
-                          << *(MemLoc.Ptr) << "\n");
-        return true;
-      }
-      N++;
-      auto Res = AA->getModRefInfo(&I, MemLoc);
-      if (isModSet(Res)) {
-        LLVM_DEBUG(dbgs() << "Aliasing failed on " << I << " for "
-                          << *(MemLoc.Ptr) << "\n");
-        return true;
-      }
-    }
-  LLVM_DEBUG(dbgs() << "Aliasing okay for " << *(MemLoc.Ptr) << "\n");
-  return false;
-}
-
+                        Alignment.value(), SawUnorderedAtomic, AATags, 
+                        *SafetyInfo); 
+ 
+  // Set up the preheader to have a definition of the value.  It is the live-out 
+  // value from the preheader that uses in the loop will use. 
+  LoadInst *PreheaderLoad = new LoadInst( 
+      SomePtr->getType()->getPointerElementType(), SomePtr, 
+      SomePtr->getName() + ".promoted", Preheader->getTerminator()); 
+  if (SawUnorderedAtomic) 
+    PreheaderLoad->setOrdering(AtomicOrdering::Unordered); 
+  PreheaderLoad->setAlignment(Alignment); 
+  PreheaderLoad->setDebugLoc(DebugLoc()); 
+  if (AATags) 
+    PreheaderLoad->setAAMetadata(AATags); 
+  SSA.AddAvailableValue(Preheader, PreheaderLoad); 
+ 
+  if (MSSAU) { 
+    MemoryAccess *PreheaderLoadMemoryAccess = MSSAU->createMemoryAccessInBB( 
+        PreheaderLoad, nullptr, PreheaderLoad->getParent(), MemorySSA::End); 
+    MemoryUse *NewMemUse = cast<MemoryUse>(PreheaderLoadMemoryAccess); 
+    MSSAU->insertUse(NewMemUse, /*RenameUses=*/true); 
+  } 
+ 
+  if (MSSAU && VerifyMemorySSA) 
+    MSSAU->getMemorySSA()->verifyMemorySSA(); 
+  // Rewrite all the loads in the loop and remember all the definitions from 
+  // stores in the loop. 
+  Promoter.run(LoopUses); 
+ 
+  if (MSSAU && VerifyMemorySSA) 
+    MSSAU->getMemorySSA()->verifyMemorySSA(); 
+  // If the SSAUpdater didn't use the load in the preheader, just zap it now. 
+  if (PreheaderLoad->use_empty()) 
+    eraseInstruction(*PreheaderLoad, *SafetyInfo, CurAST, MSSAU); 
+ 
+  return true; 
+} 
+ 
+/// Returns an owning pointer to an alias set which incorporates aliasing info 
+/// from L and all subloops of L. 
+std::unique_ptr<AliasSetTracker> 
+LoopInvariantCodeMotion::collectAliasInfoForLoop(Loop *L, LoopInfo *LI, 
+                                                 AAResults *AA) { 
+  auto CurAST = std::make_unique<AliasSetTracker>(*AA); 
+ 
+  // Add everything from all the sub loops. 
+  for (Loop *InnerL : L->getSubLoops()) 
+    for (BasicBlock *BB : InnerL->blocks()) 
+      CurAST->add(*BB); 
+ 
+  // And merge in this loop (without anything from inner loops). 
+  for (BasicBlock *BB : L->blocks()) 
+    if (LI->getLoopFor(BB) == L) 
+      CurAST->add(*BB); 
+ 
+  return CurAST; 
+} 
+ 
+std::unique_ptr<AliasSetTracker> 
+LoopInvariantCodeMotion::collectAliasInfoForLoopWithMSSA( 
+    Loop *L, AAResults *AA, MemorySSAUpdater *MSSAU) { 
+  auto *MSSA = MSSAU->getMemorySSA(); 
+  auto CurAST = std::make_unique<AliasSetTracker>(*AA, MSSA, L); 
+  CurAST->addAllInstructionsInLoopUsingMSSA(); 
+  return CurAST; 
+} 
+ 
+static bool pointerInvalidatedByLoop(MemoryLocation MemLoc, 
+                                     AliasSetTracker *CurAST, Loop *CurLoop, 
+                                     AAResults *AA) { 
+  // First check to see if any of the basic blocks in CurLoop invalidate *V. 
+  bool isInvalidatedAccordingToAST = CurAST->getAliasSetFor(MemLoc).isMod(); 
+ 
+  if (!isInvalidatedAccordingToAST || !LICMN2Theshold) 
+    return isInvalidatedAccordingToAST; 
+ 
+  // Check with a diagnostic analysis if we can refine the information above. 
+  // This is to identify the limitations of using the AST. 
+  // The alias set mechanism used by LICM has a major weakness in that it 
+  // combines all things which may alias into a single set *before* asking 
+  // modref questions. As a result, a single readonly call within a loop will 
+  // collapse all loads and stores into a single alias set and report 
+  // invalidation if the loop contains any store. For example, readonly calls 
+  // with deopt states have this form and create a general alias set with all 
+  // loads and stores.  In order to get any LICM in loops containing possible 
+  // deopt states we need a more precise invalidation of checking the mod ref 
+  // info of each instruction within the loop and LI. This has a complexity of 
+  // O(N^2), so currently, it is used only as a diagnostic tool since the 
+  // default value of LICMN2Threshold is zero. 
+ 
+  // Don't look at nested loops. 
+  if (CurLoop->begin() != CurLoop->end()) 
+    return true; 
+ 
+  int N = 0; 
+  for (BasicBlock *BB : CurLoop->getBlocks()) 
+    for (Instruction &I : *BB) { 
+      if (N >= LICMN2Theshold) { 
+        LLVM_DEBUG(dbgs() << "Alasing N2 threshold exhausted for " 
+                          << *(MemLoc.Ptr) << "\n"); 
+        return true; 
+      } 
+      N++; 
+      auto Res = AA->getModRefInfo(&I, MemLoc); 
+      if (isModSet(Res)) { 
+        LLVM_DEBUG(dbgs() << "Aliasing failed on " << I << " for " 
+                          << *(MemLoc.Ptr) << "\n"); 
+        return true; 
+      } 
+    } 
+  LLVM_DEBUG(dbgs() << "Aliasing okay for " << *(MemLoc.Ptr) << "\n"); 
+  return false; 
+} 
+ 
 bool pointerInvalidatedByLoopWithMSSA(MemorySSA *MSSA, MemoryUse *MU,
                                       Loop *CurLoop, Instruction &I,
                                       SinkAndHoistLICMFlags &Flags) {
-  // For hoisting, use the walker to determine safety
+  // For hoisting, use the walker to determine safety 
   if (!Flags.getIsSink()) {
-    MemoryAccess *Source;
-    // See declaration of SetLicmMssaOptCap for usage details.
+    MemoryAccess *Source; 
+    // See declaration of SetLicmMssaOptCap for usage details. 
     if (Flags.tooManyClobberingCalls())
-      Source = MU->getDefiningAccess();
-    else {
-      Source = MSSA->getSkipSelfWalker()->getClobberingMemoryAccess(MU);
+      Source = MU->getDefiningAccess(); 
+    else { 
+      Source = MSSA->getSkipSelfWalker()->getClobberingMemoryAccess(MU); 
       Flags.incrementClobberingCalls();
-    }
-    return !MSSA->isLiveOnEntryDef(Source) &&
-           CurLoop->contains(Source->getBlock());
-  }
-
-  // For sinking, we'd need to check all Defs below this use. The getClobbering
-  // call will look on the backedge of the loop, but will check aliasing with
-  // the instructions on the previous iteration.
-  // For example:
-  // for (i ... )
-  //   load a[i] ( Use (LoE)
-  //   store a[i] ( 1 = Def (2), with 2 = Phi for the loop.
-  //   i++;
-  // The load sees no clobbering inside the loop, as the backedge alias check
-  // does phi translation, and will check aliasing against store a[i-1].
-  // However sinking the load outside the loop, below the store is incorrect.
-
-  // For now, only sink if there are no Defs in the loop, and the existing ones
-  // precede the use and are in the same block.
-  // FIXME: Increase precision: Safe to sink if Use post dominates the Def;
-  // needs PostDominatorTreeAnalysis.
-  // FIXME: More precise: no Defs that alias this Use.
+    } 
+    return !MSSA->isLiveOnEntryDef(Source) && 
+           CurLoop->contains(Source->getBlock()); 
+  } 
+ 
+  // For sinking, we'd need to check all Defs below this use. The getClobbering 
+  // call will look on the backedge of the loop, but will check aliasing with 
+  // the instructions on the previous iteration. 
+  // For example: 
+  // for (i ... ) 
+  //   load a[i] ( Use (LoE) 
+  //   store a[i] ( 1 = Def (2), with 2 = Phi for the loop. 
+  //   i++; 
+  // The load sees no clobbering inside the loop, as the backedge alias check 
+  // does phi translation, and will check aliasing against store a[i-1]. 
+  // However sinking the load outside the loop, below the store is incorrect. 
+ 
+  // For now, only sink if there are no Defs in the loop, and the existing ones 
+  // precede the use and are in the same block. 
+  // FIXME: Increase precision: Safe to sink if Use post dominates the Def; 
+  // needs PostDominatorTreeAnalysis. 
+  // FIXME: More precise: no Defs that alias this Use. 
   if (Flags.tooManyMemoryAccesses())
-    return true;
-  for (auto *BB : CurLoop->getBlocks())
+    return true; 
+  for (auto *BB : CurLoop->getBlocks()) 
     if (pointerInvalidatedByBlockWithMSSA(*BB, *MSSA, *MU))
       return true;
   // When sinking, the source block may not be part of the loop so check it.
   if (!CurLoop->contains(&I))
     return pointerInvalidatedByBlockWithMSSA(*I.getParent(), *MSSA, *MU);
 
-  return false;
-}
-
+  return false; 
+} 
+ 
 bool pointerInvalidatedByBlockWithMSSA(BasicBlock &BB, MemorySSA &MSSA,
                                        MemoryUse &MU) {
   if (const auto *Accesses = MSSA.getBlockDefs(&BB))
@@ -2350,10 +2350,10 @@ bool pointerInvalidatedByBlockWithMSSA(BasicBlock &BB, MemorySSA &MSSA,
   return false;
 }
 
-/// Little predicate that returns true if the specified basic block is in
-/// a subloop of the current one, not the current one itself.
-///
-static bool inSubLoop(BasicBlock *BB, Loop *CurLoop, LoopInfo *LI) {
-  assert(CurLoop->contains(BB) && "Only valid if BB is IN the loop");
-  return LI->getLoopFor(BB) != CurLoop;
-}
+/// Little predicate that returns true if the specified basic block is in 
+/// a subloop of the current one, not the current one itself. 
+/// 
+static bool inSubLoop(BasicBlock *BB, Loop *CurLoop, LoopInfo *LI) { 
+  assert(CurLoop->contains(BB) && "Only valid if BB is IN the loop"); 
+  return LI->getLoopFor(BB) != CurLoop; 
+}