1 files changed, 21 insertions, 40 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
index f87132ee4758..7e8f8e27a97b 100644
--- a/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
@@ -38,6 +38,7 @@
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Type.h"
 #include "llvm/IR/Value.h"
+#include "llvm/InitializePasses.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/CommandLine.h"
@@ -221,7 +222,7 @@ public:
   Value *untagPointer(IRBuilder<> &IRB, Value *PtrLong);
   bool instrumentStack(
       SmallVectorImpl<AllocaInst *> &Allocas,
-      DenseMap<AllocaInst *, std::vector<DbgDeclareInst *>> &AllocaDeclareMap,
+      DenseMap<AllocaInst *, std::vector<DbgVariableIntrinsic *>> &AllocaDbgMap,
       SmallVectorImpl<Instruction *> &RetVec, Value *StackTag);
   Value *readRegister(IRBuilder<> &IRB, StringRef Name);
   bool instrumentLandingPads(SmallVectorImpl<Instruction *> &RetVec);
@@ -284,7 +285,6 @@ private:
 
   FunctionCallee HwasanTagMemoryFunc;
   FunctionCallee HwasanGenerateTagFunc;
-  FunctionCallee HwasanThreadEnterFunc;
 
   Constant *ShadowGlobal;
 
@@ -473,9 +473,6 @@ void HWAddressSanitizer::initializeCallbacks(Module &M) {
 
   HWAsanHandleVfork =
       M.getOrInsertFunction("__hwasan_handle_vfork", IRB.getVoidTy(), IntptrTy);
-
-  HwasanThreadEnterFunc =
-      M.getOrInsertFunction("__hwasan_thread_enter", IRB.getVoidTy());
 }
 
 Value *HWAddressSanitizer::getDynamicShadowIfunc(IRBuilder<> &IRB) {
@@ -792,7 +789,7 @@ bool HWAddressSanitizer::tagAlloca(IRBuilder<> &IRB, AllocaInst *AI,
     // llvm.memset right here into either a sequence of stores, or a call to
     // hwasan_tag_memory.
     if (ShadowSize)
-      IRB.CreateMemSet(ShadowPtr, JustTag, ShadowSize, /*Align=*/1);
+      IRB.CreateMemSet(ShadowPtr, JustTag, ShadowSize, Align::None());
     if (Size != AlignedSize) {
       IRB.CreateStore(
           ConstantInt::get(Int8Ty, Size % Mapping.getObjectAlignment()),
@@ -934,34 +931,13 @@ void HWAddressSanitizer::emitPrologue(IRBuilder<> &IRB, bool WithFrameRecord) {
   Value *SlotPtr = getHwasanThreadSlotPtr(IRB, IntptrTy);
   assert(SlotPtr);
 
-  Instruction *ThreadLong = IRB.CreateLoad(IntptrTy, SlotPtr);
-
-  Function *F = IRB.GetInsertBlock()->getParent();
-  if (F->getFnAttribute("hwasan-abi").getValueAsString() == "interceptor") {
-    Value *ThreadLongEqZero =
-        IRB.CreateICmpEQ(ThreadLong, ConstantInt::get(IntptrTy, 0));
-    auto *Br = cast<BranchInst>(SplitBlockAndInsertIfThen(
-        ThreadLongEqZero, cast<Instruction>(ThreadLongEqZero)->getNextNode(),
-        false, MDBuilder(*C).createBranchWeights(1, 100000)));
-
-    IRB.SetInsertPoint(Br);
-    // FIXME: This should call a new runtime function with a custom calling
-    // convention to avoid needing to spill all arguments here.
-    IRB.CreateCall(HwasanThreadEnterFunc);
-    LoadInst *ReloadThreadLong = IRB.CreateLoad(IntptrTy, SlotPtr);
-
-    IRB.SetInsertPoint(&*Br->getSuccessor(0)->begin());
-    PHINode *ThreadLongPhi = IRB.CreatePHI(IntptrTy, 2);
-    ThreadLongPhi->addIncoming(ThreadLong, ThreadLong->getParent());
-    ThreadLongPhi->addIncoming(ReloadThreadLong, ReloadThreadLong->getParent());
-    ThreadLong = ThreadLongPhi;
-  }
-
+  Value *ThreadLong = IRB.CreateLoad(IntptrTy, SlotPtr);
   // Extract the address field from ThreadLong. Unnecessary on AArch64 with TBI.
   Value *ThreadLongMaybeUntagged =
       TargetTriple.isAArch64() ? ThreadLong : untagPointer(IRB, ThreadLong);
 
   if (WithFrameRecord) {
+    Function *F = IRB.GetInsertBlock()->getParent();
     StackBaseTag = IRB.CreateAShr(ThreadLong, 3);
 
     // Prepare ring buffer data.
@@ -1040,7 +1016,7 @@ bool HWAddressSanitizer::instrumentLandingPads(
 
 bool HWAddressSanitizer::instrumentStack(
     SmallVectorImpl<AllocaInst *> &Allocas,
-    DenseMap<AllocaInst *, std::vector<DbgDeclareInst *>> &AllocaDeclareMap,
+    DenseMap<AllocaInst *, std::vector<DbgVariableIntrinsic *>> &AllocaDbgMap,
     SmallVectorImpl<Instruction *> &RetVec, Value *StackTag) {
   // Ideally, we want to calculate tagged stack base pointer, and rewrite all
   // alloca addresses using that. Unfortunately, offsets are not known yet
@@ -1062,11 +1038,15 @@ bool HWAddressSanitizer::instrumentStack(
     AI->replaceUsesWithIf(Replacement,
                           [AILong](Use &U) { return U.getUser() != AILong; });
 
-    for (auto *DDI : AllocaDeclareMap.lookup(AI)) {
-      DIExpression *OldExpr = DDI->getExpression();
-      DIExpression *NewExpr = DIExpression::append(
-          OldExpr, {dwarf::DW_OP_LLVM_tag_offset, RetagMask(N)});
-      DDI->setArgOperand(2, MetadataAsValue::get(*C, NewExpr));
+    for (auto *DDI : AllocaDbgMap.lookup(AI)) {
+      // Prepend "tag_offset, N" to the dwarf expression.
+      // Tag offset logically applies to the alloca pointer, and it makes sense
+      // to put it at the beginning of the expression.
+      SmallVector<uint64_t, 8> NewOps = {dwarf::DW_OP_LLVM_tag_offset,
+                                         RetagMask(N)};
+      DDI->setArgOperand(
+          2, MetadataAsValue::get(*C, DIExpression::prependOpcodes(
+                                          DDI->getExpression(), NewOps)));
     }
 
     size_t Size = getAllocaSizeInBytes(*AI);
@@ -1113,7 +1093,7 @@ bool HWAddressSanitizer::sanitizeFunction(Function &F) {
   SmallVector<AllocaInst*, 8> AllocasToInstrument;
   SmallVector<Instruction*, 8> RetVec;
   SmallVector<Instruction*, 8> LandingPadVec;
-  DenseMap<AllocaInst *, std::vector<DbgDeclareInst *>> AllocaDeclareMap;
+  DenseMap<AllocaInst *, std::vector<DbgVariableIntrinsic *>> AllocaDbgMap;
   for (auto &BB : F) {
     for (auto &Inst : BB) {
       if (ClInstrumentStack)
@@ -1127,9 +1107,10 @@ bool HWAddressSanitizer::sanitizeFunction(Function &F) {
           isa<CleanupReturnInst>(Inst))
         RetVec.push_back(&Inst);
 
-      if (auto *DDI = dyn_cast<DbgDeclareInst>(&Inst))
-        if (auto *Alloca = dyn_cast_or_null<AllocaInst>(DDI->getAddress()))
-          AllocaDeclareMap[Alloca].push_back(DDI);
+      if (auto *DDI = dyn_cast<DbgVariableIntrinsic>(&Inst))
+        if (auto *Alloca =
+                dyn_cast_or_null<AllocaInst>(DDI->getVariableLocation()))
+          AllocaDbgMap[Alloca].push_back(DDI);
 
       if (InstrumentLandingPads && isa<LandingPadInst>(Inst))
         LandingPadVec.push_back(&Inst);
@@ -1172,7 +1153,7 @@ bool HWAddressSanitizer::sanitizeFunction(Function &F) {
   if (!AllocasToInstrument.empty()) {
     Value *StackTag =
         ClGenerateTagsWithCalls ? nullptr : getStackBaseTag(EntryIRB);
-    Changed |= instrumentStack(AllocasToInstrument, AllocaDeclareMap, RetVec,
+    Changed |= instrumentStack(AllocasToInstrument, AllocaDbgMap, RetVec,
                                StackTag);
   }