[tsan] Add support for pointer typed atomic stores, loads, and cmpxchg

TSan instrumentation functions for atomic stores, loads, and cmpxchg work on
integer value types. This patch adds casts before calling TSan instrumentation
functions in cases where the value is a pointer.

Differential Revision: http://reviews.llvm.org/D17833

llvm-svn: 262876

1 files changed, 31 insertions, 8 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index 9331e1d..e73a4b2 100644
--- a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -496,6 +496,11 @@ bool ThreadSanitizer::instrumentMemIntrinsic(Instruction *I) {
   return false;
 }
 
+static Value *createIntOrPtrToIntCast(Value *V, Type* Ty, IRBuilder<> &IRB) {
+  return isa<PointerType>(V->getType()) ?
+    IRB.CreatePtrToInt(V, Ty) : IRB.CreateIntCast(V, Ty, false);
+}
+
 // Both llvm and ThreadSanitizer atomic operations are based on C++11/C1x
 // standards.  For background see C++11 standard.  A slightly older, publicly
 // available draft of the standard (not entirely up-to-date, but close enough
@@ -517,9 +522,16 @@ bool ThreadSanitizer::instrumentAtomic(Instruction *I, const DataLayout &DL) {
     Type *PtrTy = Ty->getPointerTo();
     Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
                      createOrdering(&IRB, LI->getOrdering())};
-    CallInst *C = CallInst::Create(TsanAtomicLoad[Idx], Args);
-    ReplaceInstWithInst(I, C);
-
+    Type *OrigTy = cast<PointerType>(Addr->getType())->getElementType();
+    if (Ty == OrigTy) {
+      Instruction *C = CallInst::Create(TsanAtomicLoad[Idx], Args);
+      ReplaceInstWithInst(I, C);
+    } else {
+      // We are loading a pointer, so we need to cast the return value.
+      Value *C = IRB.CreateCall(TsanAtomicLoad[Idx], Args);
+      Instruction *Cast = CastInst::Create(Instruction::IntToPtr, C, OrigTy);
+      ReplaceInstWithInst(I, Cast);
+    }
   } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
     Value *Addr = SI->getPointerOperand();
     int Idx = getMemoryAccessFuncIndex(Addr, DL);
@@ -530,7 +542,7 @@ bool ThreadSanitizer::instrumentAtomic(Instruction *I, const DataLayout &DL) {
     Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
     Type *PtrTy = Ty->getPointerTo();
     Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
-                     IRB.CreateIntCast(SI->getValueOperand(), Ty, false),
+                     createIntOrPtrToIntCast(SI->getValueOperand(), Ty, IRB),
                      createOrdering(&IRB, SI->getOrdering())};
     CallInst *C = CallInst::Create(TsanAtomicStore[Idx], Args);
     ReplaceInstWithInst(I, C);
@@ -560,15 +572,26 @@ bool ThreadSanitizer::instrumentAtomic(Instruction *I, const DataLayout &DL) {
     const unsigned BitSize = ByteSize * 8;
     Type *Ty = Type::getIntNTy(IRB.getContext(), BitSize);
     Type *PtrTy = Ty->getPointerTo();
+    Value *CmpOperand =
+      createIntOrPtrToIntCast(CASI->getCompareOperand(), Ty, IRB);
+    Value *NewOperand =
+      createIntOrPtrToIntCast(CASI->getNewValOperand(), Ty, IRB);
     Value *Args[] = {IRB.CreatePointerCast(Addr, PtrTy),
-                     IRB.CreateIntCast(CASI->getCompareOperand(), Ty, false),
-                     IRB.CreateIntCast(CASI->getNewValOperand(), Ty, false),
+                     CmpOperand,
+                     NewOperand,
                      createOrdering(&IRB, CASI->getSuccessOrdering()),
                      createOrdering(&IRB, CASI->getFailureOrdering())};
     CallInst *C = IRB.CreateCall(TsanAtomicCAS[Idx], Args);
-    Value *Success = IRB.CreateICmpEQ(C, CASI->getCompareOperand());
+    Value *Success = IRB.CreateICmpEQ(C, CmpOperand);
+    Value *OldVal = C;
+    Type *OrigOldValTy = CASI->getNewValOperand()->getType();
+    if (Ty != OrigOldValTy) {
+      // The value is a pointer, so we need to cast the return value.
+      OldVal = IRB.CreateIntToPtr(C, OrigOldValTy);
+    }
 
-    Value *Res = IRB.CreateInsertValue(UndefValue::get(CASI->getType()), C, 0);
+    Value *Res =
+      IRB.CreateInsertValue(UndefValue::get(CASI->getType()), OldVal, 0);
     Res = IRB.CreateInsertValue(Res, Success, 1);
 
     I->replaceAllUsesWith(Res);