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authororivej <[email protected]>2022-02-10 16:44:49 +0300
committerDaniil Cherednik <[email protected]>2022-02-10 16:44:49 +0300
commit718c552901d703c502ccbefdfc3c9028d608b947 (patch)
tree46534a98bbefcd7b1f3faa5b52c138ab27db75b7 /contrib/libs/llvm12/lib/CodeGen/OptimizePHIs.cpp
parente9656aae26e0358d5378e5b63dcac5c8dbe0e4d0 (diff)
Restoring authorship annotation for <[email protected]>. Commit 1 of 2.
Diffstat (limited to 'contrib/libs/llvm12/lib/CodeGen/OptimizePHIs.cpp')
-rw-r--r--contrib/libs/llvm12/lib/CodeGen/OptimizePHIs.cpp420
1 files changed, 210 insertions, 210 deletions
diff --git a/contrib/libs/llvm12/lib/CodeGen/OptimizePHIs.cpp b/contrib/libs/llvm12/lib/CodeGen/OptimizePHIs.cpp
index 02a70ab801e..7ee2eba50a2 100644
--- a/contrib/libs/llvm12/lib/CodeGen/OptimizePHIs.cpp
+++ b/contrib/libs/llvm12/lib/CodeGen/OptimizePHIs.cpp
@@ -1,210 +1,210 @@
-//===- OptimizePHIs.cpp - Optimize machine instruction PHIs ---------------===//
-//
-// 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 optimizes machine instruction PHIs to take advantage of
-// opportunities created during DAG legalization.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/CodeGen/MachineBasicBlock.h"
-#include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/MachineInstr.h"
-#include "llvm/CodeGen/MachineOperand.h"
-#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/TargetRegisterInfo.h"
-#include "llvm/CodeGen/TargetSubtargetInfo.h"
-#include "llvm/InitializePasses.h"
-#include "llvm/Pass.h"
-#include <cassert>
-
-using namespace llvm;
-
-#define DEBUG_TYPE "opt-phis"
-
-STATISTIC(NumPHICycles, "Number of PHI cycles replaced");
-STATISTIC(NumDeadPHICycles, "Number of dead PHI cycles");
-
-namespace {
-
- class OptimizePHIs : public MachineFunctionPass {
- MachineRegisterInfo *MRI;
- const TargetInstrInfo *TII;
-
- public:
- static char ID; // Pass identification
-
- OptimizePHIs() : MachineFunctionPass(ID) {
- initializeOptimizePHIsPass(*PassRegistry::getPassRegistry());
- }
-
- bool runOnMachineFunction(MachineFunction &Fn) override;
-
- void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.setPreservesCFG();
- MachineFunctionPass::getAnalysisUsage(AU);
- }
-
- private:
- using InstrSet = SmallPtrSet<MachineInstr *, 16>;
- using InstrSetIterator = SmallPtrSetIterator<MachineInstr *>;
-
- bool IsSingleValuePHICycle(MachineInstr *MI, unsigned &SingleValReg,
- InstrSet &PHIsInCycle);
- bool IsDeadPHICycle(MachineInstr *MI, InstrSet &PHIsInCycle);
- bool OptimizeBB(MachineBasicBlock &MBB);
- };
-
-} // end anonymous namespace
-
-char OptimizePHIs::ID = 0;
-
-char &llvm::OptimizePHIsID = OptimizePHIs::ID;
-
-INITIALIZE_PASS(OptimizePHIs, DEBUG_TYPE,
- "Optimize machine instruction PHIs", false, false)
-
-bool OptimizePHIs::runOnMachineFunction(MachineFunction &Fn) {
- if (skipFunction(Fn.getFunction()))
- return false;
-
- MRI = &Fn.getRegInfo();
- TII = Fn.getSubtarget().getInstrInfo();
-
- // Find dead PHI cycles and PHI cycles that can be replaced by a single
- // value. InstCombine does these optimizations, but DAG legalization may
- // introduce new opportunities, e.g., when i64 values are split up for
- // 32-bit targets.
- bool Changed = false;
- for (MachineFunction::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I)
- Changed |= OptimizeBB(*I);
-
- return Changed;
-}
-
-/// IsSingleValuePHICycle - Check if MI is a PHI where all the source operands
-/// are copies of SingleValReg, possibly via copies through other PHIs. If
-/// SingleValReg is zero on entry, it is set to the register with the single
-/// non-copy value. PHIsInCycle is a set used to keep track of the PHIs that
-/// have been scanned. PHIs may be grouped by cycle, several cycles or chains.
-bool OptimizePHIs::IsSingleValuePHICycle(MachineInstr *MI,
- unsigned &SingleValReg,
- InstrSet &PHIsInCycle) {
- assert(MI->isPHI() && "IsSingleValuePHICycle expects a PHI instruction");
- Register DstReg = MI->getOperand(0).getReg();
-
- // See if we already saw this register.
- if (!PHIsInCycle.insert(MI).second)
- return true;
-
- // Don't scan crazily complex things.
- if (PHIsInCycle.size() == 16)
- return false;
-
- // Scan the PHI operands.
- for (unsigned i = 1; i != MI->getNumOperands(); i += 2) {
- Register SrcReg = MI->getOperand(i).getReg();
- if (SrcReg == DstReg)
- continue;
- MachineInstr *SrcMI = MRI->getVRegDef(SrcReg);
-
- // Skip over register-to-register moves.
- if (SrcMI && SrcMI->isCopy() && !SrcMI->getOperand(0).getSubReg() &&
- !SrcMI->getOperand(1).getSubReg() &&
- Register::isVirtualRegister(SrcMI->getOperand(1).getReg())) {
- SrcReg = SrcMI->getOperand(1).getReg();
- SrcMI = MRI->getVRegDef(SrcReg);
- }
- if (!SrcMI)
- return false;
-
- if (SrcMI->isPHI()) {
- if (!IsSingleValuePHICycle(SrcMI, SingleValReg, PHIsInCycle))
- return false;
- } else {
- // Fail if there is more than one non-phi/non-move register.
- if (SingleValReg != 0 && SingleValReg != SrcReg)
- return false;
- SingleValReg = SrcReg;
- }
- }
- return true;
-}
-
-/// IsDeadPHICycle - Check if the register defined by a PHI is only used by
-/// other PHIs in a cycle.
-bool OptimizePHIs::IsDeadPHICycle(MachineInstr *MI, InstrSet &PHIsInCycle) {
- assert(MI->isPHI() && "IsDeadPHICycle expects a PHI instruction");
- Register DstReg = MI->getOperand(0).getReg();
- assert(Register::isVirtualRegister(DstReg) &&
- "PHI destination is not a virtual register");
-
- // See if we already saw this register.
- if (!PHIsInCycle.insert(MI).second)
- return true;
-
- // Don't scan crazily complex things.
- if (PHIsInCycle.size() == 16)
- return false;
-
- for (MachineInstr &UseMI : MRI->use_nodbg_instructions(DstReg)) {
- if (!UseMI.isPHI() || !IsDeadPHICycle(&UseMI, PHIsInCycle))
- return false;
- }
-
- return true;
-}
-
-/// OptimizeBB - Remove dead PHI cycles and PHI cycles that can be replaced by
-/// a single value.
-bool OptimizePHIs::OptimizeBB(MachineBasicBlock &MBB) {
- bool Changed = false;
- for (MachineBasicBlock::iterator
- MII = MBB.begin(), E = MBB.end(); MII != E; ) {
- MachineInstr *MI = &*MII++;
- if (!MI->isPHI())
- break;
-
- // Check for single-value PHI cycles.
- unsigned SingleValReg = 0;
- InstrSet PHIsInCycle;
- if (IsSingleValuePHICycle(MI, SingleValReg, PHIsInCycle) &&
- SingleValReg != 0) {
- Register OldReg = MI->getOperand(0).getReg();
- if (!MRI->constrainRegClass(SingleValReg, MRI->getRegClass(OldReg)))
- continue;
-
- MRI->replaceRegWith(OldReg, SingleValReg);
- MI->eraseFromParent();
-
- // The kill flags on OldReg and SingleValReg may no longer be correct.
- MRI->clearKillFlags(SingleValReg);
-
- ++NumPHICycles;
- Changed = true;
- continue;
- }
-
- // Check for dead PHI cycles.
- PHIsInCycle.clear();
- if (IsDeadPHICycle(MI, PHIsInCycle)) {
- for (InstrSetIterator PI = PHIsInCycle.begin(), PE = PHIsInCycle.end();
- PI != PE; ++PI) {
- MachineInstr *PhiMI = *PI;
- if (MII == PhiMI)
- ++MII;
- PhiMI->eraseFromParent();
- }
- ++NumDeadPHICycles;
- Changed = true;
- }
- }
- return Changed;
-}
+//===- OptimizePHIs.cpp - Optimize machine instruction PHIs ---------------===//
+//
+// 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 optimizes machine instruction PHIs to take advantage of
+// opportunities created during DAG legalization.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/TargetRegisterInfo.h"
+#include "llvm/CodeGen/TargetSubtargetInfo.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Pass.h"
+#include <cassert>
+
+using namespace llvm;
+
+#define DEBUG_TYPE "opt-phis"
+
+STATISTIC(NumPHICycles, "Number of PHI cycles replaced");
+STATISTIC(NumDeadPHICycles, "Number of dead PHI cycles");
+
+namespace {
+
+ class OptimizePHIs : public MachineFunctionPass {
+ MachineRegisterInfo *MRI;
+ const TargetInstrInfo *TII;
+
+ public:
+ static char ID; // Pass identification
+
+ OptimizePHIs() : MachineFunctionPass(ID) {
+ initializeOptimizePHIsPass(*PassRegistry::getPassRegistry());
+ }
+
+ bool runOnMachineFunction(MachineFunction &Fn) override;
+
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
+ AU.setPreservesCFG();
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
+
+ private:
+ using InstrSet = SmallPtrSet<MachineInstr *, 16>;
+ using InstrSetIterator = SmallPtrSetIterator<MachineInstr *>;
+
+ bool IsSingleValuePHICycle(MachineInstr *MI, unsigned &SingleValReg,
+ InstrSet &PHIsInCycle);
+ bool IsDeadPHICycle(MachineInstr *MI, InstrSet &PHIsInCycle);
+ bool OptimizeBB(MachineBasicBlock &MBB);
+ };
+
+} // end anonymous namespace
+
+char OptimizePHIs::ID = 0;
+
+char &llvm::OptimizePHIsID = OptimizePHIs::ID;
+
+INITIALIZE_PASS(OptimizePHIs, DEBUG_TYPE,
+ "Optimize machine instruction PHIs", false, false)
+
+bool OptimizePHIs::runOnMachineFunction(MachineFunction &Fn) {
+ if (skipFunction(Fn.getFunction()))
+ return false;
+
+ MRI = &Fn.getRegInfo();
+ TII = Fn.getSubtarget().getInstrInfo();
+
+ // Find dead PHI cycles and PHI cycles that can be replaced by a single
+ // value. InstCombine does these optimizations, but DAG legalization may
+ // introduce new opportunities, e.g., when i64 values are split up for
+ // 32-bit targets.
+ bool Changed = false;
+ for (MachineFunction::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I)
+ Changed |= OptimizeBB(*I);
+
+ return Changed;
+}
+
+/// IsSingleValuePHICycle - Check if MI is a PHI where all the source operands
+/// are copies of SingleValReg, possibly via copies through other PHIs. If
+/// SingleValReg is zero on entry, it is set to the register with the single
+/// non-copy value. PHIsInCycle is a set used to keep track of the PHIs that
+/// have been scanned. PHIs may be grouped by cycle, several cycles or chains.
+bool OptimizePHIs::IsSingleValuePHICycle(MachineInstr *MI,
+ unsigned &SingleValReg,
+ InstrSet &PHIsInCycle) {
+ assert(MI->isPHI() && "IsSingleValuePHICycle expects a PHI instruction");
+ Register DstReg = MI->getOperand(0).getReg();
+
+ // See if we already saw this register.
+ if (!PHIsInCycle.insert(MI).second)
+ return true;
+
+ // Don't scan crazily complex things.
+ if (PHIsInCycle.size() == 16)
+ return false;
+
+ // Scan the PHI operands.
+ for (unsigned i = 1; i != MI->getNumOperands(); i += 2) {
+ Register SrcReg = MI->getOperand(i).getReg();
+ if (SrcReg == DstReg)
+ continue;
+ MachineInstr *SrcMI = MRI->getVRegDef(SrcReg);
+
+ // Skip over register-to-register moves.
+ if (SrcMI && SrcMI->isCopy() && !SrcMI->getOperand(0).getSubReg() &&
+ !SrcMI->getOperand(1).getSubReg() &&
+ Register::isVirtualRegister(SrcMI->getOperand(1).getReg())) {
+ SrcReg = SrcMI->getOperand(1).getReg();
+ SrcMI = MRI->getVRegDef(SrcReg);
+ }
+ if (!SrcMI)
+ return false;
+
+ if (SrcMI->isPHI()) {
+ if (!IsSingleValuePHICycle(SrcMI, SingleValReg, PHIsInCycle))
+ return false;
+ } else {
+ // Fail if there is more than one non-phi/non-move register.
+ if (SingleValReg != 0 && SingleValReg != SrcReg)
+ return false;
+ SingleValReg = SrcReg;
+ }
+ }
+ return true;
+}
+
+/// IsDeadPHICycle - Check if the register defined by a PHI is only used by
+/// other PHIs in a cycle.
+bool OptimizePHIs::IsDeadPHICycle(MachineInstr *MI, InstrSet &PHIsInCycle) {
+ assert(MI->isPHI() && "IsDeadPHICycle expects a PHI instruction");
+ Register DstReg = MI->getOperand(0).getReg();
+ assert(Register::isVirtualRegister(DstReg) &&
+ "PHI destination is not a virtual register");
+
+ // See if we already saw this register.
+ if (!PHIsInCycle.insert(MI).second)
+ return true;
+
+ // Don't scan crazily complex things.
+ if (PHIsInCycle.size() == 16)
+ return false;
+
+ for (MachineInstr &UseMI : MRI->use_nodbg_instructions(DstReg)) {
+ if (!UseMI.isPHI() || !IsDeadPHICycle(&UseMI, PHIsInCycle))
+ return false;
+ }
+
+ return true;
+}
+
+/// OptimizeBB - Remove dead PHI cycles and PHI cycles that can be replaced by
+/// a single value.
+bool OptimizePHIs::OptimizeBB(MachineBasicBlock &MBB) {
+ bool Changed = false;
+ for (MachineBasicBlock::iterator
+ MII = MBB.begin(), E = MBB.end(); MII != E; ) {
+ MachineInstr *MI = &*MII++;
+ if (!MI->isPHI())
+ break;
+
+ // Check for single-value PHI cycles.
+ unsigned SingleValReg = 0;
+ InstrSet PHIsInCycle;
+ if (IsSingleValuePHICycle(MI, SingleValReg, PHIsInCycle) &&
+ SingleValReg != 0) {
+ Register OldReg = MI->getOperand(0).getReg();
+ if (!MRI->constrainRegClass(SingleValReg, MRI->getRegClass(OldReg)))
+ continue;
+
+ MRI->replaceRegWith(OldReg, SingleValReg);
+ MI->eraseFromParent();
+
+ // The kill flags on OldReg and SingleValReg may no longer be correct.
+ MRI->clearKillFlags(SingleValReg);
+
+ ++NumPHICycles;
+ Changed = true;
+ continue;
+ }
+
+ // Check for dead PHI cycles.
+ PHIsInCycle.clear();
+ if (IsDeadPHICycle(MI, PHIsInCycle)) {
+ for (InstrSetIterator PI = PHIsInCycle.begin(), PE = PHIsInCycle.end();
+ PI != PE; ++PI) {
+ MachineInstr *PhiMI = *PI;
+ if (MII == PhiMI)
+ ++MII;
+ PhiMI->eraseFromParent();
+ }
+ ++NumDeadPHICycles;
+ Changed = true;
+ }
+ }
+ return Changed;
+}