//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "shadowstackgc"
#include "llvm/CodeGen/GCs.h"
#include "llvm/ADT/StringExtras.h"
-#include "llvm/CodeGen/GCStrategy.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/Module.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Support/IRBuilder.h"
+#include "llvm/IR/CallSite.h"
+#include "llvm/IR/GCStrategy.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Module.h"
using namespace llvm;
+#define DEBUG_TYPE "shadowstackgc"
+
namespace {
- class VISIBILITY_HIDDEN ShadowStackGC : public GCStrategy {
- /// RootChain - This is the global linked-list that contains the chain of GC
- /// roots.
- GlobalVariable *Head;
-
- /// StackEntryTy - Abstract type of a link in the shadow stack.
- ///
- const StructType *StackEntryTy;
-
- /// Roots - GC roots in the current function. Each is a pair of the
- /// intrinsic call and its corresponding alloca.
- std::vector<std::pair<CallInst*,AllocaInst*> > Roots;
-
- public:
- ShadowStackGC();
-
- bool initializeCustomLowering(Module &M);
- bool performCustomLowering(Function &F);
-
- private:
- bool IsNullValue(Value *V);
- Constant *GetFrameMap(Function &F);
- const Type* GetConcreteStackEntryType(Function &F);
- void CollectRoots(Function &F);
- static GetElementPtrInst *CreateGEP(LLVMContext &Context,
- IRBuilder<> &B, Value *BasePtr,
- int Idx1, const char *Name);
- static GetElementPtrInst *CreateGEP(LLVMContext &Context,
- IRBuilder<> &B, Value *BasePtr,
- int Idx1, int Idx2, const char *Name);
- };
+class ShadowStackGC : public GCStrategy {
+ /// RootChain - This is the global linked-list that contains the chain of GC
+ /// roots.
+ GlobalVariable *Head;
+ /// StackEntryTy - Abstract type of a link in the shadow stack.
+ ///
+ StructType *StackEntryTy;
+ StructType *FrameMapTy;
+
+ /// Roots - GC roots in the current function. Each is a pair of the
+ /// intrinsic call and its corresponding alloca.
+ std::vector<std::pair<CallInst *, AllocaInst *>> Roots;
+
+public:
+ ShadowStackGC();
+
+ bool initializeCustomLowering(Module &M) override;
+ bool performCustomLowering(Function &F) override;
+
+private:
+ bool IsNullValue(Value *V);
+ Constant *GetFrameMap(Function &F);
+ Type *GetConcreteStackEntryType(Function &F);
+ void CollectRoots(Function &F);
+ static GetElementPtrInst *CreateGEP(LLVMContext &Context, IRBuilder<> &B,
+ Value *BasePtr, int Idx1,
+ const char *Name);
+ static GetElementPtrInst *CreateGEP(LLVMContext &Context, IRBuilder<> &B,
+ Value *BasePtr, int Idx1, int Idx2,
+ const char *Name);
+};
}
static GCRegistry::Add<ShadowStackGC>
-X("shadow-stack", "Very portable GC for uncooperative code generators");
+ X("shadow-stack", "Very portable GC for uncooperative code generators");
namespace {
- /// EscapeEnumerator - This is a little algorithm to find all escape points
- /// from a function so that "finally"-style code can be inserted. In addition
- /// to finding the existing return and unwind instructions, it also (if
- /// necessary) transforms any call instructions into invokes and sends them to
- /// a landing pad.
- ///
- /// It's wrapped up in a state machine using the same transform C# uses for
- /// 'yield return' enumerators, This transform allows it to be non-allocating.
- class VISIBILITY_HIDDEN EscapeEnumerator {
- Function &F;
- const char *CleanupBBName;
-
- // State.
- int State;
- Function::iterator StateBB, StateE;
- IRBuilder<> Builder;
-
- public:
- EscapeEnumerator(Function &F, const char *N = "cleanup")
+/// EscapeEnumerator - This is a little algorithm to find all escape points
+/// from a function so that "finally"-style code can be inserted. In addition
+/// to finding the existing return and unwind instructions, it also (if
+/// necessary) transforms any call instructions into invokes and sends them to
+/// a landing pad.
+///
+/// It's wrapped up in a state machine using the same transform C# uses for
+/// 'yield return' enumerators, This transform allows it to be non-allocating.
+class EscapeEnumerator {
+ Function &F;
+ const char *CleanupBBName;
+
+ // State.
+ int State;
+ Function::iterator StateBB, StateE;
+ IRBuilder<> Builder;
+
+public:
+ EscapeEnumerator(Function &F, const char *N = "cleanup")
: F(F), CleanupBBName(N), State(0), Builder(F.getContext()) {}
- IRBuilder<> *Next() {
- switch (State) {
- default:
- return 0;
-
- case 0:
- StateBB = F.begin();
- StateE = F.end();
- State = 1;
-
- case 1:
- // Find all 'return' and 'unwind' instructions.
- while (StateBB != StateE) {
- BasicBlock *CurBB = StateBB++;
-
- // Branches and invokes do not escape, only unwind and return do.
- TerminatorInst *TI = CurBB->getTerminator();
- if (!isa<UnwindInst>(TI) && !isa<ReturnInst>(TI))
- continue;
-
- Builder.SetInsertPoint(TI->getParent(), TI);
- return &Builder;
- }
-
- State = 2;
-
- // Find all 'call' instructions.
- SmallVector<Instruction*,16> Calls;
- for (Function::iterator BB = F.begin(),
- E = F.end(); BB != E; ++BB)
- for (BasicBlock::iterator II = BB->begin(),
- EE = BB->end(); II != EE; ++II)
- if (CallInst *CI = dyn_cast<CallInst>(II))
- if (!CI->getCalledFunction() ||
- !CI->getCalledFunction()->getIntrinsicID())
- Calls.push_back(CI);
-
- if (Calls.empty())
- return 0;
-
- // Create a cleanup block.
- BasicBlock *CleanupBB = BasicBlock::Create(CleanupBBName, &F);
- UnwindInst *UI = new UnwindInst(CleanupBB);
-
- // Transform the 'call' instructions into 'invoke's branching to the
- // cleanup block. Go in reverse order to make prettier BB names.
- SmallVector<Value*,16> Args;
- for (unsigned I = Calls.size(); I != 0; ) {
- CallInst *CI = cast<CallInst>(Calls[--I]);
-
- // Split the basic block containing the function call.
- BasicBlock *CallBB = CI->getParent();
- BasicBlock *NewBB =
- CallBB->splitBasicBlock(CI, CallBB->getName() + ".cont");
+ IRBuilder<> *Next() {
+ switch (State) {
+ default:
+ return nullptr;
- // Remove the unconditional branch inserted at the end of CallBB.
- CallBB->getInstList().pop_back();
- NewBB->getInstList().remove(CI);
-
- // Create a new invoke instruction.
- Args.clear();
- Args.append(CI->op_begin() + 1, CI->op_end());
-
- InvokeInst *II = InvokeInst::Create(CI->getOperand(0),
- NewBB, CleanupBB,
- Args.begin(), Args.end(),
- CI->getName(), CallBB);
- II->setCallingConv(CI->getCallingConv());
- II->setAttributes(CI->getAttributes());
- CI->replaceAllUsesWith(II);
- delete CI;
- }
-
- Builder.SetInsertPoint(UI->getParent(), UI);
+ case 0:
+ StateBB = F.begin();
+ StateE = F.end();
+ State = 1;
+
+ case 1:
+ // Find all 'return', 'resume', and 'unwind' instructions.
+ while (StateBB != StateE) {
+ BasicBlock *CurBB = StateBB++;
+
+ // Branches and invokes do not escape, only unwind, resume, and return
+ // do.
+ TerminatorInst *TI = CurBB->getTerminator();
+ if (!isa<ReturnInst>(TI) && !isa<ResumeInst>(TI))
+ continue;
+
+ Builder.SetInsertPoint(TI->getParent(), TI);
return &Builder;
}
+
+ State = 2;
+
+ // Find all 'call' instructions.
+ SmallVector<Instruction *, 16> Calls;
+ for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
+ for (BasicBlock::iterator II = BB->begin(), EE = BB->end(); II != EE;
+ ++II)
+ if (CallInst *CI = dyn_cast<CallInst>(II))
+ if (!CI->getCalledFunction() ||
+ !CI->getCalledFunction()->getIntrinsicID())
+ Calls.push_back(CI);
+
+ if (Calls.empty())
+ return nullptr;
+
+ // Create a cleanup block.
+ LLVMContext &C = F.getContext();
+ BasicBlock *CleanupBB = BasicBlock::Create(C, CleanupBBName, &F);
+ Type *ExnTy =
+ StructType::get(Type::getInt8PtrTy(C), Type::getInt32Ty(C), nullptr);
+ Constant *PersFn = F.getParent()->getOrInsertFunction(
+ "__gcc_personality_v0", FunctionType::get(Type::getInt32Ty(C), true));
+ LandingPadInst *LPad =
+ LandingPadInst::Create(ExnTy, PersFn, 1, "cleanup.lpad", CleanupBB);
+ LPad->setCleanup(true);
+ ResumeInst *RI = ResumeInst::Create(LPad, CleanupBB);
+
+ // Transform the 'call' instructions into 'invoke's branching to the
+ // cleanup block. Go in reverse order to make prettier BB names.
+ SmallVector<Value *, 16> Args;
+ for (unsigned I = Calls.size(); I != 0;) {
+ CallInst *CI = cast<CallInst>(Calls[--I]);
+
+ // Split the basic block containing the function call.
+ BasicBlock *CallBB = CI->getParent();
+ BasicBlock *NewBB =
+ CallBB->splitBasicBlock(CI, CallBB->getName() + ".cont");
+
+ // Remove the unconditional branch inserted at the end of CallBB.
+ CallBB->getInstList().pop_back();
+ NewBB->getInstList().remove(CI);
+
+ // Create a new invoke instruction.
+ Args.clear();
+ CallSite CS(CI);
+ Args.append(CS.arg_begin(), CS.arg_end());
+
+ InvokeInst *II =
+ InvokeInst::Create(CI->getCalledValue(), NewBB, CleanupBB, Args,
+ CI->getName(), CallBB);
+ II->setCallingConv(CI->getCallingConv());
+ II->setAttributes(CI->getAttributes());
+ CI->replaceAllUsesWith(II);
+ delete CI;
+ }
+
+ Builder.SetInsertPoint(RI->getParent(), RI);
+ return &Builder;
}
- };
+ }
+};
}
// -----------------------------------------------------------------------------
-void llvm::linkShadowStackGC() { }
+void llvm::linkShadowStackGC() {}
-ShadowStackGC::ShadowStackGC() : Head(0), StackEntryTy(0) {
+ShadowStackGC::ShadowStackGC() : Head(nullptr), StackEntryTy(nullptr) {
InitRoots = true;
CustomRoots = true;
}
Constant *ShadowStackGC::GetFrameMap(Function &F) {
// doInitialization creates the abstract type of this value.
- LLVMContext &Context = F.getContext();
-
- Type *VoidPtr = PointerType::getUnqual(Type::Int8Ty);
+ Type *VoidPtr = Type::getInt8PtrTy(F.getContext());
// Truncate the ShadowStackDescriptor if some metadata is null.
unsigned NumMeta = 0;
- SmallVector<Constant*,16> Metadata;
+ SmallVector<Constant *, 16> Metadata;
for (unsigned I = 0; I != Roots.size(); ++I) {
- Constant *C = cast<Constant>(Roots[I].first->getOperand(2));
+ Constant *C = cast<Constant>(Roots[I].first->getArgOperand(1));
if (!C->isNullValue())
NumMeta = I + 1;
Metadata.push_back(ConstantExpr::getBitCast(C, VoidPtr));
}
+ Metadata.resize(NumMeta);
+
+ Type *Int32Ty = Type::getInt32Ty(F.getContext());
Constant *BaseElts[] = {
- ConstantInt::get(Type::Int32Ty, Roots.size(), false),
- ConstantInt::get(Type::Int32Ty, NumMeta, false),
+ ConstantInt::get(Int32Ty, Roots.size(), false),
+ ConstantInt::get(Int32Ty, NumMeta, false),
};
Constant *DescriptorElts[] = {
- Context.getConstantStruct(BaseElts, 2),
- Context.getConstantArray(Context.getArrayType(VoidPtr, NumMeta),
- Metadata.begin(), NumMeta)
- };
+ ConstantStruct::get(FrameMapTy, BaseElts),
+ ConstantArray::get(ArrayType::get(VoidPtr, NumMeta), Metadata)};
- Constant *FrameMap = Context.getConstantStruct(DescriptorElts, 2);
+ Type *EltTys[] = {DescriptorElts[0]->getType(), DescriptorElts[1]->getType()};
+ StructType *STy = StructType::create(EltTys, "gc_map." + utostr(NumMeta));
- std::string TypeName("gc_map.");
- TypeName += utostr(NumMeta);
- F.getParent()->addTypeName(TypeName, FrameMap->getType());
+ Constant *FrameMap = ConstantStruct::get(STy, DescriptorElts);
// FIXME: Is this actually dangerous as WritingAnLLVMPass.html claims? Seems
// that, short of multithreaded LLVM, it should be safe; all that is
// (which uses a FunctionPassManager (which segfaults (not asserts) if
// provided a ModulePass))).
Constant *GV = new GlobalVariable(*F.getParent(), FrameMap->getType(), true,
- GlobalVariable::InternalLinkage,
- FrameMap, "__gc_" + F.getName());
+ GlobalVariable::InternalLinkage, FrameMap,
+ "__gc_" + F.getName());
- Constant *GEPIndices[2] = { ConstantInt::get(Type::Int32Ty, 0),
- ConstantInt::get(Type::Int32Ty, 0) };
- return Context.getConstantExprGetElementPtr(GV, GEPIndices, 2);
+ Constant *GEPIndices[2] = {
+ ConstantInt::get(Type::getInt32Ty(F.getContext()), 0),
+ ConstantInt::get(Type::getInt32Ty(F.getContext()), 0)};
+ return ConstantExpr::getGetElementPtr(GV, GEPIndices);
}
-const Type* ShadowStackGC::GetConcreteStackEntryType(Function &F) {
+Type *ShadowStackGC::GetConcreteStackEntryType(Function &F) {
// doInitialization creates the generic version of this type.
- std::vector<const Type*> EltTys;
+ std::vector<Type *> EltTys;
EltTys.push_back(StackEntryTy);
for (size_t I = 0; I != Roots.size(); I++)
EltTys.push_back(Roots[I].second->getAllocatedType());
- Type *Ty = StructType::get(EltTys);
-
- std::string TypeName("gc_stackentry.");
- TypeName += F.getName();
- F.getParent()->addTypeName(TypeName, Ty);
- return Ty;
+ return StructType::create(EltTys, "gc_stackentry." + F.getName().str());
}
/// doInitialization - If this module uses the GC intrinsics, find them now. If
// int32_t NumMeta; // Number of metadata descriptors. May be < NumRoots.
// void *Meta[]; // May be absent for roots without metadata.
// };
- std::vector<const Type*> EltTys;
- EltTys.push_back(Type::Int32Ty); // 32 bits is ok up to a 32GB stack frame. :)
- EltTys.push_back(Type::Int32Ty); // Specifies length of variable length array.
- StructType *FrameMapTy = StructType::get(EltTys);
- M.addTypeName("gc_map", FrameMapTy);
+ std::vector<Type *> EltTys;
+ // 32 bits is ok up to a 32GB stack frame. :)
+ EltTys.push_back(Type::getInt32Ty(M.getContext()));
+ // Specifies length of variable length array.
+ EltTys.push_back(Type::getInt32Ty(M.getContext()));
+ FrameMapTy = StructType::create(EltTys, "gc_map");
PointerType *FrameMapPtrTy = PointerType::getUnqual(FrameMapTy);
// struct StackEntry {
// FrameMap *Map; // Pointer to constant FrameMap.
// void *Roots[]; // Stack roots (in-place array, so we pretend).
// };
- OpaqueType *RecursiveTy = OpaqueType::get();
+
+ StackEntryTy = StructType::create(M.getContext(), "gc_stackentry");
EltTys.clear();
- EltTys.push_back(PointerType::getUnqual(RecursiveTy));
+ EltTys.push_back(PointerType::getUnqual(StackEntryTy));
EltTys.push_back(FrameMapPtrTy);
- PATypeHolder LinkTyH = StructType::get(EltTys);
-
- RecursiveTy->refineAbstractTypeTo(LinkTyH.get());
- StackEntryTy = cast<StructType>(LinkTyH.get());
- const PointerType *StackEntryPtrTy = PointerType::getUnqual(StackEntryTy);
- M.addTypeName("gc_stackentry", LinkTyH.get()); // FIXME: Is this safe from
- // a FunctionPass?
+ StackEntryTy->setBody(EltTys);
+ PointerType *StackEntryPtrTy = PointerType::getUnqual(StackEntryTy);
// Get the root chain if it already exists.
Head = M.getGlobalVariable("llvm_gc_root_chain");
if (!Head) {
// If the root chain does not exist, insert a new one with linkonce
// linkage!
- Head = new GlobalVariable(M, StackEntryPtrTy, false,
- GlobalValue::LinkOnceAnyLinkage,
- M.getContext().getNullValue(StackEntryPtrTy),
- "llvm_gc_root_chain");
+ Head = new GlobalVariable(
+ M, StackEntryPtrTy, false, GlobalValue::LinkOnceAnyLinkage,
+ Constant::getNullValue(StackEntryPtrTy), "llvm_gc_root_chain");
} else if (Head->hasExternalLinkage() && Head->isDeclaration()) {
- Head->setInitializer(M.getContext().getNullValue(StackEntryPtrTy));
+ Head->setInitializer(Constant::getNullValue(StackEntryPtrTy));
Head->setLinkage(GlobalValue::LinkOnceAnyLinkage);
}
assert(Roots.empty() && "Not cleaned up?");
- SmallVector<std::pair<CallInst*,AllocaInst*>,16> MetaRoots;
+ SmallVector<std::pair<CallInst *, AllocaInst *>, 16> MetaRoots;
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
for (BasicBlock::iterator II = BB->begin(), E = BB->end(); II != E;)
if (IntrinsicInst *CI = dyn_cast<IntrinsicInst>(II++))
if (Function *F = CI->getCalledFunction())
if (F->getIntrinsicID() == Intrinsic::gcroot) {
- std::pair<CallInst*,AllocaInst*> Pair = std::make_pair(
- CI, cast<AllocaInst>(CI->getOperand(1)->stripPointerCasts()));
- if (IsNullValue(CI->getOperand(2)))
+ std::pair<CallInst *, AllocaInst *> Pair = std::make_pair(
+ CI,
+ cast<AllocaInst>(CI->getArgOperand(0)->stripPointerCasts()));
+ if (IsNullValue(CI->getArgOperand(1)))
Roots.push_back(Pair);
else
MetaRoots.push_back(Pair);
Roots.insert(Roots.begin(), MetaRoots.begin(), MetaRoots.end());
}
-GetElementPtrInst *
-ShadowStackGC::CreateGEP(LLVMContext &Context, IRBuilder<> &B, Value *BasePtr,
- int Idx, int Idx2, const char *Name) {
- Value *Indices[] = { ConstantInt::get(Type::Int32Ty, 0),
- ConstantInt::get(Type::Int32Ty, Idx),
- ConstantInt::get(Type::Int32Ty, Idx2) };
- Value* Val = B.CreateGEP(BasePtr, Indices, Indices + 3, Name);
+GetElementPtrInst *ShadowStackGC::CreateGEP(LLVMContext &Context,
+ IRBuilder<> &B, Value *BasePtr,
+ int Idx, int Idx2,
+ const char *Name) {
+ Value *Indices[] = {ConstantInt::get(Type::getInt32Ty(Context), 0),
+ ConstantInt::get(Type::getInt32Ty(Context), Idx),
+ ConstantInt::get(Type::getInt32Ty(Context), Idx2)};
+ Value *Val = B.CreateGEP(BasePtr, Indices, Name);
assert(isa<GetElementPtrInst>(Val) && "Unexpected folded constant");
return dyn_cast<GetElementPtrInst>(Val);
}
-GetElementPtrInst *
-ShadowStackGC::CreateGEP(LLVMContext &Context, IRBuilder<> &B, Value *BasePtr,
- int Idx, const char *Name) {
- Value *Indices[] = { ConstantInt::get(Type::Int32Ty, 0),
- ConstantInt::get(Type::Int32Ty, Idx) };
- Value *Val = B.CreateGEP(BasePtr, Indices, Indices + 2, Name);
+GetElementPtrInst *ShadowStackGC::CreateGEP(LLVMContext &Context,
+ IRBuilder<> &B, Value *BasePtr,
+ int Idx, const char *Name) {
+ Value *Indices[] = {ConstantInt::get(Type::getInt32Ty(Context), 0),
+ ConstantInt::get(Type::getInt32Ty(Context), Idx)};
+ Value *Val = B.CreateGEP(BasePtr, Indices, Name);
assert(isa<GetElementPtrInst>(Val) && "Unexpected folded constant");
/// runOnFunction - Insert code to maintain the shadow stack.
bool ShadowStackGC::performCustomLowering(Function &F) {
LLVMContext &Context = F.getContext();
-
+
// Find calls to llvm.gcroot.
CollectRoots(F);
// Build the constant map and figure the type of the shadow stack entry.
Value *FrameMap = GetFrameMap(F);
- const Type *ConcreteStackEntryTy = GetConcreteStackEntryType(F);
+ Type *ConcreteStackEntryTy = GetConcreteStackEntryType(F);
// Build the shadow stack entry at the very start of the function.
BasicBlock::iterator IP = F.getEntryBlock().begin();
IRBuilder<> AtEntry(IP->getParent(), IP);
- Instruction *StackEntry = AtEntry.CreateAlloca(ConcreteStackEntryTy, 0,
- "gc_frame");
+ Instruction *StackEntry =
+ AtEntry.CreateAlloca(ConcreteStackEntryTy, nullptr, "gc_frame");
- while (isa<AllocaInst>(IP)) ++IP;
+ while (isa<AllocaInst>(IP))
+ ++IP;
AtEntry.SetInsertPoint(IP->getParent(), IP);
// Initialize the map pointer and load the current head of the shadow stack.
- Instruction *CurrentHead = AtEntry.CreateLoad(Head, "gc_currhead");
- Instruction *EntryMapPtr = CreateGEP(Context, AtEntry, StackEntry,
- 0,1,"gc_frame.map");
- AtEntry.CreateStore(FrameMap, EntryMapPtr);
+ Instruction *CurrentHead = AtEntry.CreateLoad(Head, "gc_currhead");
+ Instruction *EntryMapPtr =
+ CreateGEP(Context, AtEntry, StackEntry, 0, 1, "gc_frame.map");
+ AtEntry.CreateStore(FrameMap, EntryMapPtr);
// After all the allocas...
for (unsigned I = 0, E = Roots.size(); I != E; ++I) {
// really necessary (the collector would never see the intermediate state at
// runtime), but it's nicer not to push the half-initialized entry onto the
// shadow stack.
- while (isa<StoreInst>(IP)) ++IP;
+ while (isa<StoreInst>(IP))
+ ++IP;
AtEntry.SetInsertPoint(IP->getParent(), IP);
// Push the entry onto the shadow stack.
- Instruction *EntryNextPtr = CreateGEP(Context, AtEntry,
- StackEntry,0,0,"gc_frame.next");
- Instruction *NewHeadVal = CreateGEP(Context, AtEntry,
- StackEntry, 0, "gc_newhead");
+ Instruction *EntryNextPtr =
+ CreateGEP(Context, AtEntry, StackEntry, 0, 0, "gc_frame.next");
+ Instruction *NewHeadVal =
+ CreateGEP(Context, AtEntry, StackEntry, 0, "gc_newhead");
AtEntry.CreateStore(CurrentHead, EntryNextPtr);
AtEntry.CreateStore(NewHeadVal, Head);
while (IRBuilder<> *AtExit = EE.Next()) {
// Pop the entry from the shadow stack. Don't reuse CurrentHead from
// AtEntry, since that would make the value live for the entire function.
- Instruction *EntryNextPtr2 = CreateGEP(Context, *AtExit, StackEntry, 0, 0,
- "gc_frame.next");
+ Instruction *EntryNextPtr2 =
+ CreateGEP(Context, *AtExit, StackEntry, 0, 0, "gc_frame.next");
Value *SavedHead = AtExit->CreateLoad(EntryNextPtr2, "gc_savedhead");
- AtExit->CreateStore(SavedHead, Head);
+ AtExit->CreateStore(SavedHead, Head);
}
// Delete the original allocas (which are no longer used) and the intrinsic
projects / oota-llvm.git / blobdiff