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authororivej <[email protected]>2022-02-10 16:45:01 +0300
committerDaniil Cherednik <[email protected]>2022-02-10 16:45:01 +0300
commit2d37894b1b037cf24231090eda8589bbb44fb6fc (patch)
treebe835aa92c6248212e705f25388ebafcf84bc7a1 /contrib/libs/llvm12/lib/CodeGen/StackProtector.cpp
parent718c552901d703c502ccbefdfc3c9028d608b947 (diff)
Restoring authorship annotation for <[email protected]>. Commit 2 of 2.
Diffstat (limited to 'contrib/libs/llvm12/lib/CodeGen/StackProtector.cpp')
-rw-r--r--contrib/libs/llvm12/lib/CodeGen/StackProtector.cpp1166
1 files changed, 583 insertions, 583 deletions
diff --git a/contrib/libs/llvm12/lib/CodeGen/StackProtector.cpp b/contrib/libs/llvm12/lib/CodeGen/StackProtector.cpp
index c2dbc80ead1..10c6dcbdb04 100644
--- a/contrib/libs/llvm12/lib/CodeGen/StackProtector.cpp
+++ b/contrib/libs/llvm12/lib/CodeGen/StackProtector.cpp
@@ -1,475 +1,475 @@
-//===- StackProtector.cpp - Stack Protector Insertion ---------------------===//
-//
-// 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 inserts stack protectors into functions which need them. A variable
-// with a random value in it is stored onto the stack before the local variables
-// are allocated. Upon exiting the block, the stored value is checked. If it's
-// changed, then there was some sort of violation and the program aborts.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/CodeGen/StackProtector.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/BranchProbabilityInfo.h"
-#include "llvm/Analysis/EHPersonalities.h"
-#include "llvm/Analysis/MemoryLocation.h"
-#include "llvm/Analysis/OptimizationRemarkEmitter.h"
-#include "llvm/CodeGen/Passes.h"
-#include "llvm/CodeGen/TargetLowering.h"
-#include "llvm/CodeGen/TargetPassConfig.h"
-#include "llvm/CodeGen/TargetSubtargetInfo.h"
-#include "llvm/IR/Attributes.h"
-#include "llvm/IR/BasicBlock.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/DataLayout.h"
-#include "llvm/IR/DebugInfo.h"
-#include "llvm/IR/DebugLoc.h"
-#include "llvm/IR/DerivedTypes.h"
-#include "llvm/IR/Dominators.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/IRBuilder.h"
-#include "llvm/IR/Instruction.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/IntrinsicInst.h"
-#include "llvm/IR/Intrinsics.h"
-#include "llvm/IR/MDBuilder.h"
-#include "llvm/IR/Module.h"
-#include "llvm/IR/Type.h"
-#include "llvm/IR/User.h"
-#include "llvm/InitializePasses.h"
-#include "llvm/Pass.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetOptions.h"
-#include <utility>
-
-using namespace llvm;
-
-#define DEBUG_TYPE "stack-protector"
-
-STATISTIC(NumFunProtected, "Number of functions protected");
-STATISTIC(NumAddrTaken, "Number of local variables that have their address"
- " taken.");
-
-static cl::opt<bool> EnableSelectionDAGSP("enable-selectiondag-sp",
- cl::init(true), cl::Hidden);
-
-char StackProtector::ID = 0;
-
-StackProtector::StackProtector() : FunctionPass(ID), SSPBufferSize(8) {
- initializeStackProtectorPass(*PassRegistry::getPassRegistry());
-}
-
-INITIALIZE_PASS_BEGIN(StackProtector, DEBUG_TYPE,
- "Insert stack protectors", false, true)
-INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
-INITIALIZE_PASS_END(StackProtector, DEBUG_TYPE,
- "Insert stack protectors", false, true)
-
-FunctionPass *llvm::createStackProtectorPass() { return new StackProtector(); }
-
-void StackProtector::getAnalysisUsage(AnalysisUsage &AU) const {
- AU.addRequired<TargetPassConfig>();
- AU.addPreserved<DominatorTreeWrapperPass>();
-}
-
-bool StackProtector::runOnFunction(Function &Fn) {
- F = &Fn;
- M = F->getParent();
- DominatorTreeWrapperPass *DTWP =
- getAnalysisIfAvailable<DominatorTreeWrapperPass>();
- DT = DTWP ? &DTWP->getDomTree() : nullptr;
- TM = &getAnalysis<TargetPassConfig>().getTM<TargetMachine>();
- Trip = TM->getTargetTriple();
- TLI = TM->getSubtargetImpl(Fn)->getTargetLowering();
- HasPrologue = false;
- HasIRCheck = false;
-
- Attribute Attr = Fn.getFnAttribute("stack-protector-buffer-size");
- if (Attr.isStringAttribute() &&
- Attr.getValueAsString().getAsInteger(10, SSPBufferSize))
- return false; // Invalid integer string
-
- if (!RequiresStackProtector())
- return false;
-
- // TODO(etienneb): Functions with funclets are not correctly supported now.
- // Do nothing if this is funclet-based personality.
- if (Fn.hasPersonalityFn()) {
- EHPersonality Personality = classifyEHPersonality(Fn.getPersonalityFn());
- if (isFuncletEHPersonality(Personality))
- return false;
- }
-
- ++NumFunProtected;
- return InsertStackProtectors();
-}
-
-/// \param [out] IsLarge is set to true if a protectable array is found and
-/// it is "large" ( >= ssp-buffer-size). In the case of a structure with
-/// multiple arrays, this gets set if any of them is large.
-bool StackProtector::ContainsProtectableArray(Type *Ty, bool &IsLarge,
- bool Strong,
- bool InStruct) const {
- if (!Ty)
- return false;
- if (ArrayType *AT = dyn_cast<ArrayType>(Ty)) {
- if (!AT->getElementType()->isIntegerTy(8)) {
- // If we're on a non-Darwin platform or we're inside of a structure, don't
- // add stack protectors unless the array is a character array.
- // However, in strong mode any array, regardless of type and size,
- // triggers a protector.
- if (!Strong && (InStruct || !Trip.isOSDarwin()))
- return false;
- }
-
- // If an array has more than SSPBufferSize bytes of allocated space, then we
- // emit stack protectors.
- if (SSPBufferSize <= M->getDataLayout().getTypeAllocSize(AT)) {
- IsLarge = true;
- return true;
- }
-
- if (Strong)
- // Require a protector for all arrays in strong mode
- return true;
- }
-
- const StructType *ST = dyn_cast<StructType>(Ty);
- if (!ST)
- return false;
-
- bool NeedsProtector = false;
- for (StructType::element_iterator I = ST->element_begin(),
- E = ST->element_end();
- I != E; ++I)
- if (ContainsProtectableArray(*I, IsLarge, Strong, true)) {
- // If the element is a protectable array and is large (>= SSPBufferSize)
- // then we are done. If the protectable array is not large, then
- // keep looking in case a subsequent element is a large array.
- if (IsLarge)
- return true;
- NeedsProtector = true;
- }
-
- return NeedsProtector;
-}
-
-bool StackProtector::HasAddressTaken(const Instruction *AI,
- uint64_t AllocSize) {
- const DataLayout &DL = M->getDataLayout();
- for (const User *U : AI->users()) {
- const auto *I = cast<Instruction>(U);
- // If this instruction accesses memory make sure it doesn't access beyond
- // the bounds of the allocated object.
- Optional<MemoryLocation> MemLoc = MemoryLocation::getOrNone(I);
+//===- StackProtector.cpp - Stack Protector Insertion ---------------------===//
+//
+// 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 inserts stack protectors into functions which need them. A variable
+// with a random value in it is stored onto the stack before the local variables
+// are allocated. Upon exiting the block, the stored value is checked. If it's
+// changed, then there was some sort of violation and the program aborts.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/StackProtector.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/BranchProbabilityInfo.h"
+#include "llvm/Analysis/EHPersonalities.h"
+#include "llvm/Analysis/MemoryLocation.h"
+#include "llvm/Analysis/OptimizationRemarkEmitter.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/CodeGen/TargetLowering.h"
+#include "llvm/CodeGen/TargetPassConfig.h"
+#include "llvm/CodeGen/TargetSubtargetInfo.h"
+#include "llvm/IR/Attributes.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DebugInfo.h"
+#include "llvm/IR/DebugLoc.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Type.h"
+#include "llvm/IR/User.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetOptions.h"
+#include <utility>
+
+using namespace llvm;
+
+#define DEBUG_TYPE "stack-protector"
+
+STATISTIC(NumFunProtected, "Number of functions protected");
+STATISTIC(NumAddrTaken, "Number of local variables that have their address"
+ " taken.");
+
+static cl::opt<bool> EnableSelectionDAGSP("enable-selectiondag-sp",
+ cl::init(true), cl::Hidden);
+
+char StackProtector::ID = 0;
+
+StackProtector::StackProtector() : FunctionPass(ID), SSPBufferSize(8) {
+ initializeStackProtectorPass(*PassRegistry::getPassRegistry());
+}
+
+INITIALIZE_PASS_BEGIN(StackProtector, DEBUG_TYPE,
+ "Insert stack protectors", false, true)
+INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
+INITIALIZE_PASS_END(StackProtector, DEBUG_TYPE,
+ "Insert stack protectors", false, true)
+
+FunctionPass *llvm::createStackProtectorPass() { return new StackProtector(); }
+
+void StackProtector::getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addRequired<TargetPassConfig>();
+ AU.addPreserved<DominatorTreeWrapperPass>();
+}
+
+bool StackProtector::runOnFunction(Function &Fn) {
+ F = &Fn;
+ M = F->getParent();
+ DominatorTreeWrapperPass *DTWP =
+ getAnalysisIfAvailable<DominatorTreeWrapperPass>();
+ DT = DTWP ? &DTWP->getDomTree() : nullptr;
+ TM = &getAnalysis<TargetPassConfig>().getTM<TargetMachine>();
+ Trip = TM->getTargetTriple();
+ TLI = TM->getSubtargetImpl(Fn)->getTargetLowering();
+ HasPrologue = false;
+ HasIRCheck = false;
+
+ Attribute Attr = Fn.getFnAttribute("stack-protector-buffer-size");
+ if (Attr.isStringAttribute() &&
+ Attr.getValueAsString().getAsInteger(10, SSPBufferSize))
+ return false; // Invalid integer string
+
+ if (!RequiresStackProtector())
+ return false;
+
+ // TODO(etienneb): Functions with funclets are not correctly supported now.
+ // Do nothing if this is funclet-based personality.
+ if (Fn.hasPersonalityFn()) {
+ EHPersonality Personality = classifyEHPersonality(Fn.getPersonalityFn());
+ if (isFuncletEHPersonality(Personality))
+ return false;
+ }
+
+ ++NumFunProtected;
+ return InsertStackProtectors();
+}
+
+/// \param [out] IsLarge is set to true if a protectable array is found and
+/// it is "large" ( >= ssp-buffer-size). In the case of a structure with
+/// multiple arrays, this gets set if any of them is large.
+bool StackProtector::ContainsProtectableArray(Type *Ty, bool &IsLarge,
+ bool Strong,
+ bool InStruct) const {
+ if (!Ty)
+ return false;
+ if (ArrayType *AT = dyn_cast<ArrayType>(Ty)) {
+ if (!AT->getElementType()->isIntegerTy(8)) {
+ // If we're on a non-Darwin platform or we're inside of a structure, don't
+ // add stack protectors unless the array is a character array.
+ // However, in strong mode any array, regardless of type and size,
+ // triggers a protector.
+ if (!Strong && (InStruct || !Trip.isOSDarwin()))
+ return false;
+ }
+
+ // If an array has more than SSPBufferSize bytes of allocated space, then we
+ // emit stack protectors.
+ if (SSPBufferSize <= M->getDataLayout().getTypeAllocSize(AT)) {
+ IsLarge = true;
+ return true;
+ }
+
+ if (Strong)
+ // Require a protector for all arrays in strong mode
+ return true;
+ }
+
+ const StructType *ST = dyn_cast<StructType>(Ty);
+ if (!ST)
+ return false;
+
+ bool NeedsProtector = false;
+ for (StructType::element_iterator I = ST->element_begin(),
+ E = ST->element_end();
+ I != E; ++I)
+ if (ContainsProtectableArray(*I, IsLarge, Strong, true)) {
+ // If the element is a protectable array and is large (>= SSPBufferSize)
+ // then we are done. If the protectable array is not large, then
+ // keep looking in case a subsequent element is a large array.
+ if (IsLarge)
+ return true;
+ NeedsProtector = true;
+ }
+
+ return NeedsProtector;
+}
+
+bool StackProtector::HasAddressTaken(const Instruction *AI,
+ uint64_t AllocSize) {
+ const DataLayout &DL = M->getDataLayout();
+ for (const User *U : AI->users()) {
+ const auto *I = cast<Instruction>(U);
+ // If this instruction accesses memory make sure it doesn't access beyond
+ // the bounds of the allocated object.
+ Optional<MemoryLocation> MemLoc = MemoryLocation::getOrNone(I);
if (MemLoc.hasValue() && MemLoc->Size.hasValue() &&
MemLoc->Size.getValue() > AllocSize)
- return true;
- switch (I->getOpcode()) {
- case Instruction::Store:
- if (AI == cast<StoreInst>(I)->getValueOperand())
- return true;
- break;
- case Instruction::AtomicCmpXchg:
- // cmpxchg conceptually includes both a load and store from the same
- // location. So, like store, the value being stored is what matters.
- if (AI == cast<AtomicCmpXchgInst>(I)->getNewValOperand())
- return true;
- break;
- case Instruction::PtrToInt:
- if (AI == cast<PtrToIntInst>(I)->getOperand(0))
- return true;
- break;
- case Instruction::Call: {
- // Ignore intrinsics that do not become real instructions.
- // TODO: Narrow this to intrinsics that have store-like effects.
- const auto *CI = cast<CallInst>(I);
+ return true;
+ switch (I->getOpcode()) {
+ case Instruction::Store:
+ if (AI == cast<StoreInst>(I)->getValueOperand())
+ return true;
+ break;
+ case Instruction::AtomicCmpXchg:
+ // cmpxchg conceptually includes both a load and store from the same
+ // location. So, like store, the value being stored is what matters.
+ if (AI == cast<AtomicCmpXchgInst>(I)->getNewValOperand())
+ return true;
+ break;
+ case Instruction::PtrToInt:
+ if (AI == cast<PtrToIntInst>(I)->getOperand(0))
+ return true;
+ break;
+ case Instruction::Call: {
+ // Ignore intrinsics that do not become real instructions.
+ // TODO: Narrow this to intrinsics that have store-like effects.
+ const auto *CI = cast<CallInst>(I);
if (!CI->isDebugOrPseudoInst() && !CI->isLifetimeStartOrEnd())
- return true;
- break;
- }
- case Instruction::Invoke:
- return true;
- case Instruction::GetElementPtr: {
- // If the GEP offset is out-of-bounds, or is non-constant and so has to be
- // assumed to be potentially out-of-bounds, then any memory access that
- // would use it could also be out-of-bounds meaning stack protection is
- // required.
- const GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
- unsigned TypeSize = DL.getIndexTypeSizeInBits(I->getType());
- APInt Offset(TypeSize, 0);
- APInt MaxOffset(TypeSize, AllocSize);
- if (!GEP->accumulateConstantOffset(DL, Offset) || Offset.ugt(MaxOffset))
- return true;
- // Adjust AllocSize to be the space remaining after this offset.
- if (HasAddressTaken(I, AllocSize - Offset.getLimitedValue()))
- return true;
- break;
- }
- case Instruction::BitCast:
- case Instruction::Select:
- case Instruction::AddrSpaceCast:
- if (HasAddressTaken(I, AllocSize))
- return true;
- break;
- case Instruction::PHI: {
- // Keep track of what PHI nodes we have already visited to ensure
- // they are only visited once.
- const auto *PN = cast<PHINode>(I);
- if (VisitedPHIs.insert(PN).second)
- if (HasAddressTaken(PN, AllocSize))
- return true;
- break;
- }
- case Instruction::Load:
- case Instruction::AtomicRMW:
- case Instruction::Ret:
- // These instructions take an address operand, but have load-like or
- // other innocuous behavior that should not trigger a stack protector.
- // atomicrmw conceptually has both load and store semantics, but the
- // value being stored must be integer; so if a pointer is being stored,
- // we'll catch it in the PtrToInt case above.
- break;
- default:
- // Conservatively return true for any instruction that takes an address
- // operand, but is not handled above.
- return true;
- }
- }
- return false;
-}
-
-/// Search for the first call to the llvm.stackprotector intrinsic and return it
-/// if present.
-static const CallInst *findStackProtectorIntrinsic(Function &F) {
- for (const BasicBlock &BB : F)
- for (const Instruction &I : BB)
+ return true;
+ break;
+ }
+ case Instruction::Invoke:
+ return true;
+ case Instruction::GetElementPtr: {
+ // If the GEP offset is out-of-bounds, or is non-constant and so has to be
+ // assumed to be potentially out-of-bounds, then any memory access that
+ // would use it could also be out-of-bounds meaning stack protection is
+ // required.
+ const GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
+ unsigned TypeSize = DL.getIndexTypeSizeInBits(I->getType());
+ APInt Offset(TypeSize, 0);
+ APInt MaxOffset(TypeSize, AllocSize);
+ if (!GEP->accumulateConstantOffset(DL, Offset) || Offset.ugt(MaxOffset))
+ return true;
+ // Adjust AllocSize to be the space remaining after this offset.
+ if (HasAddressTaken(I, AllocSize - Offset.getLimitedValue()))
+ return true;
+ break;
+ }
+ case Instruction::BitCast:
+ case Instruction::Select:
+ case Instruction::AddrSpaceCast:
+ if (HasAddressTaken(I, AllocSize))
+ return true;
+ break;
+ case Instruction::PHI: {
+ // Keep track of what PHI nodes we have already visited to ensure
+ // they are only visited once.
+ const auto *PN = cast<PHINode>(I);
+ if (VisitedPHIs.insert(PN).second)
+ if (HasAddressTaken(PN, AllocSize))
+ return true;
+ break;
+ }
+ case Instruction::Load:
+ case Instruction::AtomicRMW:
+ case Instruction::Ret:
+ // These instructions take an address operand, but have load-like or
+ // other innocuous behavior that should not trigger a stack protector.
+ // atomicrmw conceptually has both load and store semantics, but the
+ // value being stored must be integer; so if a pointer is being stored,
+ // we'll catch it in the PtrToInt case above.
+ break;
+ default:
+ // Conservatively return true for any instruction that takes an address
+ // operand, but is not handled above.
+ return true;
+ }
+ }
+ return false;
+}
+
+/// Search for the first call to the llvm.stackprotector intrinsic and return it
+/// if present.
+static const CallInst *findStackProtectorIntrinsic(Function &F) {
+ for (const BasicBlock &BB : F)
+ for (const Instruction &I : BB)
if (const auto *II = dyn_cast<IntrinsicInst>(&I))
if (II->getIntrinsicID() == Intrinsic::stackprotector)
return II;
- return nullptr;
-}
-
-/// Check whether or not this function needs a stack protector based
-/// upon the stack protector level.
-///
-/// We use two heuristics: a standard (ssp) and strong (sspstrong).
-/// The standard heuristic which will add a guard variable to functions that
-/// call alloca with a either a variable size or a size >= SSPBufferSize,
-/// functions with character buffers larger than SSPBufferSize, and functions
-/// with aggregates containing character buffers larger than SSPBufferSize. The
-/// strong heuristic will add a guard variables to functions that call alloca
-/// regardless of size, functions with any buffer regardless of type and size,
-/// functions with aggregates that contain any buffer regardless of type and
-/// size, and functions that contain stack-based variables that have had their
-/// address taken.
-bool StackProtector::RequiresStackProtector() {
- bool Strong = false;
- bool NeedsProtector = false;
-
- if (F->hasFnAttribute(Attribute::SafeStack))
- return false;
-
- // We are constructing the OptimizationRemarkEmitter on the fly rather than
- // using the analysis pass to avoid building DominatorTree and LoopInfo which
- // are not available this late in the IR pipeline.
- OptimizationRemarkEmitter ORE(F);
-
- if (F->hasFnAttribute(Attribute::StackProtectReq)) {
- ORE.emit([&]() {
- return OptimizationRemark(DEBUG_TYPE, "StackProtectorRequested", F)
- << "Stack protection applied to function "
- << ore::NV("Function", F)
- << " due to a function attribute or command-line switch";
- });
- NeedsProtector = true;
- Strong = true; // Use the same heuristic as strong to determine SSPLayout
- } else if (F->hasFnAttribute(Attribute::StackProtectStrong))
- Strong = true;
- else if (!F->hasFnAttribute(Attribute::StackProtect))
- return false;
-
- for (const BasicBlock &BB : *F) {
- for (const Instruction &I : BB) {
- if (const AllocaInst *AI = dyn_cast<AllocaInst>(&I)) {
- if (AI->isArrayAllocation()) {
- auto RemarkBuilder = [&]() {
- return OptimizationRemark(DEBUG_TYPE, "StackProtectorAllocaOrArray",
- &I)
- << "Stack protection applied to function "
- << ore::NV("Function", F)
- << " due to a call to alloca or use of a variable length "
- "array";
- };
- if (const auto *CI = dyn_cast<ConstantInt>(AI->getArraySize())) {
- if (CI->getLimitedValue(SSPBufferSize) >= SSPBufferSize) {
- // A call to alloca with size >= SSPBufferSize requires
- // stack protectors.
- Layout.insert(std::make_pair(AI,
- MachineFrameInfo::SSPLK_LargeArray));
- ORE.emit(RemarkBuilder);
- NeedsProtector = true;
- } else if (Strong) {
- // Require protectors for all alloca calls in strong mode.
- Layout.insert(std::make_pair(AI,
- MachineFrameInfo::SSPLK_SmallArray));
- ORE.emit(RemarkBuilder);
- NeedsProtector = true;
- }
- } else {
- // A call to alloca with a variable size requires protectors.
- Layout.insert(std::make_pair(AI,
- MachineFrameInfo::SSPLK_LargeArray));
- ORE.emit(RemarkBuilder);
- NeedsProtector = true;
- }
- continue;
- }
-
- bool IsLarge = false;
- if (ContainsProtectableArray(AI->getAllocatedType(), IsLarge, Strong)) {
- Layout.insert(std::make_pair(AI, IsLarge
- ? MachineFrameInfo::SSPLK_LargeArray
- : MachineFrameInfo::SSPLK_SmallArray));
- ORE.emit([&]() {
- return OptimizationRemark(DEBUG_TYPE, "StackProtectorBuffer", &I)
- << "Stack protection applied to function "
- << ore::NV("Function", F)
- << " due to a stack allocated buffer or struct containing a "
- "buffer";
- });
- NeedsProtector = true;
- continue;
- }
-
- if (Strong && HasAddressTaken(AI, M->getDataLayout().getTypeAllocSize(
- AI->getAllocatedType()))) {
- ++NumAddrTaken;
- Layout.insert(std::make_pair(AI, MachineFrameInfo::SSPLK_AddrOf));
- ORE.emit([&]() {
- return OptimizationRemark(DEBUG_TYPE, "StackProtectorAddressTaken",
- &I)
- << "Stack protection applied to function "
- << ore::NV("Function", F)
- << " due to the address of a local variable being taken";
- });
- NeedsProtector = true;
- }
- // Clear any PHIs that we visited, to make sure we examine all uses of
- // any subsequent allocas that we look at.
- VisitedPHIs.clear();
- }
- }
- }
-
- return NeedsProtector;
-}
-
-/// Create a stack guard loading and populate whether SelectionDAG SSP is
-/// supported.
-static Value *getStackGuard(const TargetLoweringBase *TLI, Module *M,
- IRBuilder<> &B,
- bool *SupportsSelectionDAGSP = nullptr) {
+ return nullptr;
+}
+
+/// Check whether or not this function needs a stack protector based
+/// upon the stack protector level.
+///
+/// We use two heuristics: a standard (ssp) and strong (sspstrong).
+/// The standard heuristic which will add a guard variable to functions that
+/// call alloca with a either a variable size or a size >= SSPBufferSize,
+/// functions with character buffers larger than SSPBufferSize, and functions
+/// with aggregates containing character buffers larger than SSPBufferSize. The
+/// strong heuristic will add a guard variables to functions that call alloca
+/// regardless of size, functions with any buffer regardless of type and size,
+/// functions with aggregates that contain any buffer regardless of type and
+/// size, and functions that contain stack-based variables that have had their
+/// address taken.
+bool StackProtector::RequiresStackProtector() {
+ bool Strong = false;
+ bool NeedsProtector = false;
+
+ if (F->hasFnAttribute(Attribute::SafeStack))
+ return false;
+
+ // We are constructing the OptimizationRemarkEmitter on the fly rather than
+ // using the analysis pass to avoid building DominatorTree and LoopInfo which
+ // are not available this late in the IR pipeline.
+ OptimizationRemarkEmitter ORE(F);
+
+ if (F->hasFnAttribute(Attribute::StackProtectReq)) {
+ ORE.emit([&]() {
+ return OptimizationRemark(DEBUG_TYPE, "StackProtectorRequested", F)
+ << "Stack protection applied to function "
+ << ore::NV("Function", F)
+ << " due to a function attribute or command-line switch";
+ });
+ NeedsProtector = true;
+ Strong = true; // Use the same heuristic as strong to determine SSPLayout
+ } else if (F->hasFnAttribute(Attribute::StackProtectStrong))
+ Strong = true;
+ else if (!F->hasFnAttribute(Attribute::StackProtect))
+ return false;
+
+ for (const BasicBlock &BB : *F) {
+ for (const Instruction &I : BB) {
+ if (const AllocaInst *AI = dyn_cast<AllocaInst>(&I)) {
+ if (AI->isArrayAllocation()) {
+ auto RemarkBuilder = [&]() {
+ return OptimizationRemark(DEBUG_TYPE, "StackProtectorAllocaOrArray",
+ &I)
+ << "Stack protection applied to function "
+ << ore::NV("Function", F)
+ << " due to a call to alloca or use of a variable length "
+ "array";
+ };
+ if (const auto *CI = dyn_cast<ConstantInt>(AI->getArraySize())) {
+ if (CI->getLimitedValue(SSPBufferSize) >= SSPBufferSize) {
+ // A call to alloca with size >= SSPBufferSize requires
+ // stack protectors.
+ Layout.insert(std::make_pair(AI,
+ MachineFrameInfo::SSPLK_LargeArray));
+ ORE.emit(RemarkBuilder);
+ NeedsProtector = true;
+ } else if (Strong) {
+ // Require protectors for all alloca calls in strong mode.
+ Layout.insert(std::make_pair(AI,
+ MachineFrameInfo::SSPLK_SmallArray));
+ ORE.emit(RemarkBuilder);
+ NeedsProtector = true;
+ }
+ } else {
+ // A call to alloca with a variable size requires protectors.
+ Layout.insert(std::make_pair(AI,
+ MachineFrameInfo::SSPLK_LargeArray));
+ ORE.emit(RemarkBuilder);
+ NeedsProtector = true;
+ }
+ continue;
+ }
+
+ bool IsLarge = false;
+ if (ContainsProtectableArray(AI->getAllocatedType(), IsLarge, Strong)) {
+ Layout.insert(std::make_pair(AI, IsLarge
+ ? MachineFrameInfo::SSPLK_LargeArray
+ : MachineFrameInfo::SSPLK_SmallArray));
+ ORE.emit([&]() {
+ return OptimizationRemark(DEBUG_TYPE, "StackProtectorBuffer", &I)
+ << "Stack protection applied to function "
+ << ore::NV("Function", F)
+ << " due to a stack allocated buffer or struct containing a "
+ "buffer";
+ });
+ NeedsProtector = true;
+ continue;
+ }
+
+ if (Strong && HasAddressTaken(AI, M->getDataLayout().getTypeAllocSize(
+ AI->getAllocatedType()))) {
+ ++NumAddrTaken;
+ Layout.insert(std::make_pair(AI, MachineFrameInfo::SSPLK_AddrOf));
+ ORE.emit([&]() {
+ return OptimizationRemark(DEBUG_TYPE, "StackProtectorAddressTaken",
+ &I)
+ << "Stack protection applied to function "
+ << ore::NV("Function", F)
+ << " due to the address of a local variable being taken";
+ });
+ NeedsProtector = true;
+ }
+ // Clear any PHIs that we visited, to make sure we examine all uses of
+ // any subsequent allocas that we look at.
+ VisitedPHIs.clear();
+ }
+ }
+ }
+
+ return NeedsProtector;
+}
+
+/// Create a stack guard loading and populate whether SelectionDAG SSP is
+/// supported.
+static Value *getStackGuard(const TargetLoweringBase *TLI, Module *M,
+ IRBuilder<> &B,
+ bool *SupportsSelectionDAGSP = nullptr) {
Value *Guard = TLI->getIRStackGuard(B);
auto GuardMode = TLI->getTargetMachine().Options.StackProtectorGuard;
if ((GuardMode == llvm::StackProtectorGuards::TLS ||
GuardMode == llvm::StackProtectorGuards::None) && Guard)
- return B.CreateLoad(B.getInt8PtrTy(), Guard, true, "StackGuard");
-
- // Use SelectionDAG SSP handling, since there isn't an IR guard.
- //
- // This is more or less weird, since we optionally output whether we
- // should perform a SelectionDAG SP here. The reason is that it's strictly
- // defined as !TLI->getIRStackGuard(B), where getIRStackGuard is also
- // mutating. There is no way to get this bit without mutating the IR, so
- // getting this bit has to happen in this right time.
- //
- // We could have define a new function TLI::supportsSelectionDAGSP(), but that
- // will put more burden on the backends' overriding work, especially when it
- // actually conveys the same information getIRStackGuard() already gives.
- if (SupportsSelectionDAGSP)
- *SupportsSelectionDAGSP = true;
- TLI->insertSSPDeclarations(*M);
- return B.CreateCall(Intrinsic::getDeclaration(M, Intrinsic::stackguard));
-}
-
-/// Insert code into the entry block that stores the stack guard
-/// variable onto the stack:
-///
-/// entry:
-/// StackGuardSlot = alloca i8*
-/// StackGuard = <stack guard>
-/// call void @llvm.stackprotector(StackGuard, StackGuardSlot)
-///
-/// Returns true if the platform/triple supports the stackprotectorcreate pseudo
-/// node.
-static bool CreatePrologue(Function *F, Module *M, ReturnInst *RI,
- const TargetLoweringBase *TLI, AllocaInst *&AI) {
- bool SupportsSelectionDAGSP = false;
- IRBuilder<> B(&F->getEntryBlock().front());
- PointerType *PtrTy = Type::getInt8PtrTy(RI->getContext());
- AI = B.CreateAlloca(PtrTy, nullptr, "StackGuardSlot");
-
- Value *GuardSlot = getStackGuard(TLI, M, B, &SupportsSelectionDAGSP);
- B.CreateCall(Intrinsic::getDeclaration(M, Intrinsic::stackprotector),
- {GuardSlot, AI});
- return SupportsSelectionDAGSP;
-}
-
-/// InsertStackProtectors - Insert code into the prologue and epilogue of the
-/// function.
-///
-/// - The prologue code loads and stores the stack guard onto the stack.
-/// - The epilogue checks the value stored in the prologue against the original
-/// value. It calls __stack_chk_fail if they differ.
-bool StackProtector::InsertStackProtectors() {
- // If the target wants to XOR the frame pointer into the guard value, it's
- // impossible to emit the check in IR, so the target *must* support stack
- // protection in SDAG.
- bool SupportsSelectionDAGSP =
- TLI->useStackGuardXorFP() ||
- (EnableSelectionDAGSP && !TM->Options.EnableFastISel &&
- !TM->Options.EnableGlobalISel);
- AllocaInst *AI = nullptr; // Place on stack that stores the stack guard.
-
- for (Function::iterator I = F->begin(), E = F->end(); I != E;) {
- BasicBlock *BB = &*I++;
- ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator());
- if (!RI)
- continue;
-
- // Generate prologue instrumentation if not already generated.
- if (!HasPrologue) {
- HasPrologue = true;
- SupportsSelectionDAGSP &= CreatePrologue(F, M, RI, TLI, AI);
- }
-
- // SelectionDAG based code generation. Nothing else needs to be done here.
- // The epilogue instrumentation is postponed to SelectionDAG.
- if (SupportsSelectionDAGSP)
- break;
-
- // Find the stack guard slot if the prologue was not created by this pass
- // itself via a previous call to CreatePrologue().
- if (!AI) {
- const CallInst *SPCall = findStackProtectorIntrinsic(*F);
- assert(SPCall && "Call to llvm.stackprotector is missing");
- AI = cast<AllocaInst>(SPCall->getArgOperand(1));
- }
-
- // Set HasIRCheck to true, so that SelectionDAG will not generate its own
- // version. SelectionDAG called 'shouldEmitSDCheck' to check whether
- // instrumentation has already been generated.
- HasIRCheck = true;
-
+ return B.CreateLoad(B.getInt8PtrTy(), Guard, true, "StackGuard");
+
+ // Use SelectionDAG SSP handling, since there isn't an IR guard.
+ //
+ // This is more or less weird, since we optionally output whether we
+ // should perform a SelectionDAG SP here. The reason is that it's strictly
+ // defined as !TLI->getIRStackGuard(B), where getIRStackGuard is also
+ // mutating. There is no way to get this bit without mutating the IR, so
+ // getting this bit has to happen in this right time.
+ //
+ // We could have define a new function TLI::supportsSelectionDAGSP(), but that
+ // will put more burden on the backends' overriding work, especially when it
+ // actually conveys the same information getIRStackGuard() already gives.
+ if (SupportsSelectionDAGSP)
+ *SupportsSelectionDAGSP = true;
+ TLI->insertSSPDeclarations(*M);
+ return B.CreateCall(Intrinsic::getDeclaration(M, Intrinsic::stackguard));
+}
+
+/// Insert code into the entry block that stores the stack guard
+/// variable onto the stack:
+///
+/// entry:
+/// StackGuardSlot = alloca i8*
+/// StackGuard = <stack guard>
+/// call void @llvm.stackprotector(StackGuard, StackGuardSlot)
+///
+/// Returns true if the platform/triple supports the stackprotectorcreate pseudo
+/// node.
+static bool CreatePrologue(Function *F, Module *M, ReturnInst *RI,
+ const TargetLoweringBase *TLI, AllocaInst *&AI) {
+ bool SupportsSelectionDAGSP = false;
+ IRBuilder<> B(&F->getEntryBlock().front());
+ PointerType *PtrTy = Type::getInt8PtrTy(RI->getContext());
+ AI = B.CreateAlloca(PtrTy, nullptr, "StackGuardSlot");
+
+ Value *GuardSlot = getStackGuard(TLI, M, B, &SupportsSelectionDAGSP);
+ B.CreateCall(Intrinsic::getDeclaration(M, Intrinsic::stackprotector),
+ {GuardSlot, AI});
+ return SupportsSelectionDAGSP;
+}
+
+/// InsertStackProtectors - Insert code into the prologue and epilogue of the
+/// function.
+///
+/// - The prologue code loads and stores the stack guard onto the stack.
+/// - The epilogue checks the value stored in the prologue against the original
+/// value. It calls __stack_chk_fail if they differ.
+bool StackProtector::InsertStackProtectors() {
+ // If the target wants to XOR the frame pointer into the guard value, it's
+ // impossible to emit the check in IR, so the target *must* support stack
+ // protection in SDAG.
+ bool SupportsSelectionDAGSP =
+ TLI->useStackGuardXorFP() ||
+ (EnableSelectionDAGSP && !TM->Options.EnableFastISel &&
+ !TM->Options.EnableGlobalISel);
+ AllocaInst *AI = nullptr; // Place on stack that stores the stack guard.
+
+ for (Function::iterator I = F->begin(), E = F->end(); I != E;) {
+ BasicBlock *BB = &*I++;
+ ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator());
+ if (!RI)
+ continue;
+
+ // Generate prologue instrumentation if not already generated.
+ if (!HasPrologue) {
+ HasPrologue = true;
+ SupportsSelectionDAGSP &= CreatePrologue(F, M, RI, TLI, AI);
+ }
+
+ // SelectionDAG based code generation. Nothing else needs to be done here.
+ // The epilogue instrumentation is postponed to SelectionDAG.
+ if (SupportsSelectionDAGSP)
+ break;
+
+ // Find the stack guard slot if the prologue was not created by this pass
+ // itself via a previous call to CreatePrologue().
+ if (!AI) {
+ const CallInst *SPCall = findStackProtectorIntrinsic(*F);
+ assert(SPCall && "Call to llvm.stackprotector is missing");
+ AI = cast<AllocaInst>(SPCall->getArgOperand(1));
+ }
+
+ // Set HasIRCheck to true, so that SelectionDAG will not generate its own
+ // version. SelectionDAG called 'shouldEmitSDCheck' to check whether
+ // instrumentation has already been generated.
+ HasIRCheck = true;
+
// If we're instrumenting a block with a musttail call, the check has to be
// inserted before the call rather than between it and the return. The
// verifier guarantees that a musttail call is either directly before the
@@ -485,132 +485,132 @@ bool StackProtector::InsertStackProtectors() {
CheckLoc = Prev;
}
- // Generate epilogue instrumentation. The epilogue intrumentation can be
- // function-based or inlined depending on which mechanism the target is
- // providing.
- if (Function *GuardCheck = TLI->getSSPStackGuardCheck(*M)) {
- // Generate the function-based epilogue instrumentation.
- // The target provides a guard check function, generate a call to it.
+ // Generate epilogue instrumentation. The epilogue intrumentation can be
+ // function-based or inlined depending on which mechanism the target is
+ // providing.
+ if (Function *GuardCheck = TLI->getSSPStackGuardCheck(*M)) {
+ // Generate the function-based epilogue instrumentation.
+ // The target provides a guard check function, generate a call to it.
IRBuilder<> B(CheckLoc);
- LoadInst *Guard = B.CreateLoad(B.getInt8PtrTy(), AI, true, "Guard");
- CallInst *Call = B.CreateCall(GuardCheck, {Guard});
- Call->setAttributes(GuardCheck->getAttributes());
- Call->setCallingConv(GuardCheck->getCallingConv());
- } else {
- // Generate the epilogue with inline instrumentation.
+ LoadInst *Guard = B.CreateLoad(B.getInt8PtrTy(), AI, true, "Guard");
+ CallInst *Call = B.CreateCall(GuardCheck, {Guard});
+ Call->setAttributes(GuardCheck->getAttributes());
+ Call->setCallingConv(GuardCheck->getCallingConv());
+ } else {
+ // Generate the epilogue with inline instrumentation.
// If we do not support SelectionDAG based calls, generate IR level
// calls.
- //
- // For each block with a return instruction, convert this:
- //
- // return:
- // ...
- // ret ...
- //
- // into this:
- //
- // return:
- // ...
- // %1 = <stack guard>
- // %2 = load StackGuardSlot
- // %3 = cmp i1 %1, %2
- // br i1 %3, label %SP_return, label %CallStackCheckFailBlk
- //
- // SP_return:
- // ret ...
- //
- // CallStackCheckFailBlk:
- // call void @__stack_chk_fail()
- // unreachable
-
- // Create the FailBB. We duplicate the BB every time since the MI tail
- // merge pass will merge together all of the various BB into one including
- // fail BB generated by the stack protector pseudo instruction.
- BasicBlock *FailBB = CreateFailBB();
-
- // Split the basic block before the return instruction.
+ //
+ // For each block with a return instruction, convert this:
+ //
+ // return:
+ // ...
+ // ret ...
+ //
+ // into this:
+ //
+ // return:
+ // ...
+ // %1 = <stack guard>
+ // %2 = load StackGuardSlot
+ // %3 = cmp i1 %1, %2
+ // br i1 %3, label %SP_return, label %CallStackCheckFailBlk
+ //
+ // SP_return:
+ // ret ...
+ //
+ // CallStackCheckFailBlk:
+ // call void @__stack_chk_fail()
+ // unreachable
+
+ // Create the FailBB. We duplicate the BB every time since the MI tail
+ // merge pass will merge together all of the various BB into one including
+ // fail BB generated by the stack protector pseudo instruction.
+ BasicBlock *FailBB = CreateFailBB();
+
+ // Split the basic block before the return instruction.
BasicBlock *NewBB =
BB->splitBasicBlock(CheckLoc->getIterator(), "SP_return");
-
- // Update the dominator tree if we need to.
- if (DT && DT->isReachableFromEntry(BB)) {
- DT->addNewBlock(NewBB, BB);
- DT->addNewBlock(FailBB, BB);
- }
-
- // Remove default branch instruction to the new BB.
- BB->getTerminator()->eraseFromParent();
-
- // Move the newly created basic block to the point right after the old
- // basic block so that it's in the "fall through" position.
- NewBB->moveAfter(BB);
-
- // Generate the stack protector instructions in the old basic block.
- IRBuilder<> B(BB);
- Value *Guard = getStackGuard(TLI, M, B);
- LoadInst *LI2 = B.CreateLoad(B.getInt8PtrTy(), AI, true);
- Value *Cmp = B.CreateICmpEQ(Guard, LI2);
- auto SuccessProb =
- BranchProbabilityInfo::getBranchProbStackProtector(true);
- auto FailureProb =
- BranchProbabilityInfo::getBranchProbStackProtector(false);
- MDNode *Weights = MDBuilder(F->getContext())
- .createBranchWeights(SuccessProb.getNumerator(),
- FailureProb.getNumerator());
- B.CreateCondBr(Cmp, NewBB, FailBB, Weights);
- }
- }
-
- // Return if we didn't modify any basic blocks. i.e., there are no return
- // statements in the function.
- return HasPrologue;
-}
-
-/// CreateFailBB - Create a basic block to jump to when the stack protector
-/// check fails.
-BasicBlock *StackProtector::CreateFailBB() {
- LLVMContext &Context = F->getContext();
- BasicBlock *FailBB = BasicBlock::Create(Context, "CallStackCheckFailBlk", F);
- IRBuilder<> B(FailBB);
+
+ // Update the dominator tree if we need to.
+ if (DT && DT->isReachableFromEntry(BB)) {
+ DT->addNewBlock(NewBB, BB);
+ DT->addNewBlock(FailBB, BB);
+ }
+
+ // Remove default branch instruction to the new BB.
+ BB->getTerminator()->eraseFromParent();
+
+ // Move the newly created basic block to the point right after the old
+ // basic block so that it's in the "fall through" position.
+ NewBB->moveAfter(BB);
+
+ // Generate the stack protector instructions in the old basic block.
+ IRBuilder<> B(BB);
+ Value *Guard = getStackGuard(TLI, M, B);
+ LoadInst *LI2 = B.CreateLoad(B.getInt8PtrTy(), AI, true);
+ Value *Cmp = B.CreateICmpEQ(Guard, LI2);
+ auto SuccessProb =
+ BranchProbabilityInfo::getBranchProbStackProtector(true);
+ auto FailureProb =
+ BranchProbabilityInfo::getBranchProbStackProtector(false);
+ MDNode *Weights = MDBuilder(F->getContext())
+ .createBranchWeights(SuccessProb.getNumerator(),
+ FailureProb.getNumerator());
+ B.CreateCondBr(Cmp, NewBB, FailBB, Weights);
+ }
+ }
+
+ // Return if we didn't modify any basic blocks. i.e., there are no return
+ // statements in the function.
+ return HasPrologue;
+}
+
+/// CreateFailBB - Create a basic block to jump to when the stack protector
+/// check fails.
+BasicBlock *StackProtector::CreateFailBB() {
+ LLVMContext &Context = F->getContext();
+ BasicBlock *FailBB = BasicBlock::Create(Context, "CallStackCheckFailBlk", F);
+ IRBuilder<> B(FailBB);
if (F->getSubprogram())
B.SetCurrentDebugLocation(
DILocation::get(Context, 0, 0, F->getSubprogram()));
- if (Trip.isOSOpenBSD()) {
- FunctionCallee StackChkFail = M->getOrInsertFunction(
- "__stack_smash_handler", Type::getVoidTy(Context),
- Type::getInt8PtrTy(Context));
-
- B.CreateCall(StackChkFail, B.CreateGlobalStringPtr(F->getName(), "SSH"));
- } else {
- FunctionCallee StackChkFail =
- M->getOrInsertFunction("__stack_chk_fail", Type::getVoidTy(Context));
-
- B.CreateCall(StackChkFail, {});
- }
- B.CreateUnreachable();
- return FailBB;
-}
-
-bool StackProtector::shouldEmitSDCheck(const BasicBlock &BB) const {
- return HasPrologue && !HasIRCheck && isa<ReturnInst>(BB.getTerminator());
-}
-
-void StackProtector::copyToMachineFrameInfo(MachineFrameInfo &MFI) const {
- if (Layout.empty())
- return;
-
- for (int I = 0, E = MFI.getObjectIndexEnd(); I != E; ++I) {
- if (MFI.isDeadObjectIndex(I))
- continue;
-
- const AllocaInst *AI = MFI.getObjectAllocation(I);
- if (!AI)
- continue;
-
- SSPLayoutMap::const_iterator LI = Layout.find(AI);
- if (LI == Layout.end())
- continue;
-
- MFI.setObjectSSPLayout(I, LI->second);
- }
-}
+ if (Trip.isOSOpenBSD()) {
+ FunctionCallee StackChkFail = M->getOrInsertFunction(
+ "__stack_smash_handler", Type::getVoidTy(Context),
+ Type::getInt8PtrTy(Context));
+
+ B.CreateCall(StackChkFail, B.CreateGlobalStringPtr(F->getName(), "SSH"));
+ } else {
+ FunctionCallee StackChkFail =
+ M->getOrInsertFunction("__stack_chk_fail", Type::getVoidTy(Context));
+
+ B.CreateCall(StackChkFail, {});
+ }
+ B.CreateUnreachable();
+ return FailBB;
+}
+
+bool StackProtector::shouldEmitSDCheck(const BasicBlock &BB) const {
+ return HasPrologue && !HasIRCheck && isa<ReturnInst>(BB.getTerminator());
+}
+
+void StackProtector::copyToMachineFrameInfo(MachineFrameInfo &MFI) const {
+ if (Layout.empty())
+ return;
+
+ for (int I = 0, E = MFI.getObjectIndexEnd(); I != E; ++I) {
+ if (MFI.isDeadObjectIndex(I))
+ continue;
+
+ const AllocaInst *AI = MFI.getObjectAllocation(I);
+ if (!AI)
+ continue;
+
+ SSPLayoutMap::const_iterator LI = Layout.find(AI);
+ if (LI == Layout.end())
+ continue;
+
+ MFI.setObjectSSPLayout(I, LI->second);
+ }
+}