[NFC][HWASAN] Extract insertShadowTagCheck()

[vitalybuka]

update

[fmayer]

llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp

915

I would either call both of them CheckTerm, or both of them MismatchTerm

[vitalybuka]

llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp

915

I'll rename in a separate patch.

[vitalybuka]

rename

[vitalybuka]

remove local var

llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp

this->CompileKernel = ClEnableKhwasan.getNumOccurrences() > 0
                               : CompileKernel;
 
     initializeModule();
   }
 
   void sanitizeFunction(Function &F, FunctionAnalysisManager &FAM);
 
 private:
+  struct ShadowTagCheckInfo {
+    Instruction *MismatchTerm = nullptr;
+    Value *PtrLong = nullptr;
+    Value *AddrLong = nullptr;
+    Value *PtrTag = nullptr;
+    Value *MemTag = nullptr;
+  };
   void setSSI(const StackSafetyGlobalInfo *S) { SSI = S; }
 
   void initializeModule();
   void createHwasanCtorComdat();
 
   void initializeCallbacks(Module &M);
 
   Value *getOpaqueNoopCast(IRBuilder<> &IRB, Value *Val);
 
   Value *getDynamicShadowIfunc(IRBuilder<> &IRB);
   Value *getShadowNonTls(IRBuilder<> &IRB);
 
   void untagPointerOperand(Instruction *I, Value *Addr);
   Value *memToShadow(Value *Shadow, IRBuilder<> &IRB);
 
   int64_t getAccessInfo(bool IsWrite, unsigned AccessSizeIndex);
+  ShadowTagCheckInfo insertShadowTagCheck(Value *Ptr,
+                                          Instruction *InsertBefore);
   void instrumentMemAccessOutline(Value *Ptr, bool IsWrite,
                                   unsigned AccessSizeIndex,
                                   Instruction *InsertBefore);
   void instrumentMemAccessInline(Value *Ptr, bool IsWrite,
                                  unsigned AccessSizeIndex,
                                  Instruction *InsertBefore);
   bool ignoreMemIntrinsic(MemIntrinsic *MI);
   void instrumentMemIntrinsic(MemIntrinsic *MI);
int64_t HWAddressSanitizer::getAccessInfo(bool IsWrite,
   return (CompileKernel << HWASanAccessInfo::CompileKernelShift) |
          (MatchAllTag.has_value() << HWASanAccessInfo::HasMatchAllShift) |
          (MatchAllTag.value_or(0) << HWASanAccessInfo::MatchAllShift) |
          (Recover << HWASanAccessInfo::RecoverShift) |
          (IsWrite << HWASanAccessInfo::IsWriteShift) |
          (AccessSizeIndex << HWASanAccessInfo::AccessSizeShift);
 }
 
+HWAddressSanitizer::ShadowTagCheckInfo
+HWAddressSanitizer::insertShadowTagCheck(Value *Ptr,
+                                         Instruction *InsertBefore) {
+  ShadowTagCheckInfo R;
+
+  IRBuilder<> IRB(InsertBefore);
+
+  R.PtrLong = IRB.CreatePointerCast(Ptr, IntptrTy);
+  R.PtrTag =
+      IRB.CreateTrunc(IRB.CreateLShr(R.PtrLong, PointerTagShift), Int8Ty);
+  R.AddrLong = untagPointer(IRB, R.PtrLong);
+  Value *Shadow = memToShadow(R.AddrLong, IRB);
+  R.MemTag = IRB.CreateLoad(Int8Ty, Shadow);
+  Value *TagMismatch = IRB.CreateICmpNE(R.PtrTag, R.MemTag);
+
+  if (MatchAllTag.has_value()) {
+    Value *TagNotIgnored = IRB.CreateICmpNE(
+        R.PtrTag, ConstantInt::get(R.PtrTag->getType(), *MatchAllTag));
+    TagMismatch = IRB.CreateAnd(TagMismatch, TagNotIgnored);
+  }
+
+  R.MismatchTerm =
+      SplitBlockAndInsertIfThen(TagMismatch, InsertBefore, false,
+                                MDBuilder(*C).createBranchWeights(1, 100000));
+
+  return R;
+}
+
 void HWAddressSanitizer::instrumentMemAccessOutline(Value *Ptr, bool IsWrite,
                                                     unsigned AccessSizeIndex,
                                                     Instruction *InsertBefore) {
   assert(!UsePageAliases);
   const int64_t AccessInfo = getAccessInfo(IsWrite, AccessSizeIndex);
-  IRBuilder<> IRB(InsertBefore);
 
   if (InlineFastPath) {
     // TODO.
   }
 
+  IRBuilder<> IRB(InsertBefore);
   Module *M = IRB.GetInsertBlock()->getParent()->getParent();
   Ptr = IRB.CreateBitCast(Ptr, Int8PtrTy);
   IRB.CreateCall(Intrinsic::getDeclaration(
                      M, UseShortGranules
                             ? Intrinsic::hwasan_check_memaccess_shortgranules
                             : Intrinsic::hwasan_check_memaccess),
                  {ShadowBase, Ptr, ConstantInt::get(Int32Ty, AccessInfo)});
 }
 
 void HWAddressSanitizer::instrumentMemAccessInline(Value *Ptr, bool IsWrite,
                                                    unsigned AccessSizeIndex,
                                                    Instruction *InsertBefore) {
   assert(!UsePageAliases);
   const int64_t AccessInfo = getAccessInfo(IsWrite, AccessSizeIndex);
-  IRBuilder<> IRB(InsertBefore);
-
-  Value *PtrLong = IRB.CreatePointerCast(Ptr, IntptrTy);
-  Value *PtrTag =
-      IRB.CreateTrunc(IRB.CreateLShr(PtrLong, PointerTagShift), Int8Ty);
-  Value *AddrLong = untagPointer(IRB, PtrLong);
-  Value *Shadow = memToShadow(AddrLong, IRB);
-  Value *MemTag = IRB.CreateLoad(Int8Ty, Shadow);
-  Value *TagMismatch = IRB.CreateICmpNE(PtrTag, MemTag);
-
-  if (MatchAllTag.has_value()) {
-    Value *TagNotIgnored = IRB.CreateICmpNE(
-        PtrTag, ConstantInt::get(PtrTag->getType(), *MatchAllTag));
-    TagMismatch = IRB.CreateAnd(TagMismatch, TagNotIgnored);
-  }
 
-  Instruction *CheckTerm =
-      SplitBlockAndInsertIfThen(TagMismatch, InsertBefore, false,
-                                MDBuilder(*C).createBranchWeights(1, 100000));
+  ShadowTagCheckInfo TagCheck = insertShadowTagCheck(Ptr, InsertBefore);
+  Instruction *CheckTerm = TagCheck.MismatchTerm;
 
-  IRB.SetInsertPoint(CheckTerm);
+  IRBuilder<> IRB(CheckTerm);
   Value *OutOfShortGranuleTagRange =
-      IRB.CreateICmpUGT(MemTag, ConstantInt::get(Int8Ty, 15));
+      IRB.CreateICmpUGT(TagCheck.MemTag, ConstantInt::get(Int8Ty, 15));
   Instruction *CheckFailTerm =
       SplitBlockAndInsertIfThen(OutOfShortGranuleTagRange, CheckTerm, !Recover,
                                 MDBuilder(*C).createBranchWeights(1, 100000));
 
   IRB.SetInsertPoint(CheckTerm);
-  Value *PtrLowBits = IRB.CreateTrunc(IRB.CreateAnd(PtrLong, 15), Int8Ty);
+  Value *PtrLowBits =
+      IRB.CreateTrunc(IRB.CreateAnd(TagCheck.PtrLong, 15), Int8Ty);
   PtrLowBits = IRB.CreateAdd(
       PtrLowBits, ConstantInt::get(Int8Ty, (1 << AccessSizeIndex) - 1));
-  Value *PtrLowBitsOOB = IRB.CreateICmpUGE(PtrLowBits, MemTag);
+  Value *PtrLowBitsOOB = IRB.CreateICmpUGE(PtrLowBits, TagCheck.MemTag);
   SplitBlockAndInsertIfThen(PtrLowBitsOOB, CheckTerm, false,
                             MDBuilder(*C).createBranchWeights(1, 100000),
                             (DomTreeUpdater *)nullptr, nullptr,
                             CheckFailTerm->getParent());
 
   IRB.SetInsertPoint(CheckTerm);
-  Value *InlineTagAddr = IRB.CreateOr(AddrLong, 15);
+  Value *InlineTagAddr = IRB.CreateOr(TagCheck.AddrLong, 15);
   InlineTagAddr = IRB.CreateIntToPtr(InlineTagAddr, Int8PtrTy);
   Value *InlineTag = IRB.CreateLoad(Int8Ty, InlineTagAddr);
-  Value *InlineTagMismatch = IRB.CreateICmpNE(PtrTag, InlineTag);
+  Value *InlineTagMismatch = IRB.CreateICmpNE(TagCheck.PtrTag, InlineTag);
   SplitBlockAndInsertIfThen(InlineTagMismatch, CheckTerm, false,
                             MDBuilder(*C).createBranchWeights(1, 100000),
                             (DomTreeUpdater *)nullptr, nullptr,
                             CheckFailTerm->getParent());
 
   IRB.SetInsertPoint(CheckFailTerm);
   InlineAsm *Asm;
   switch (TargetTriple.getArch()) {
   case Triple::x86_64:
     // The signal handler will find the data address in rdi.
     Asm = InlineAsm::get(
-        FunctionType::get(VoidTy, {PtrLong->getType()}, false),
+        FunctionType::get(VoidTy, {TagCheck.PtrLong->getType()}, false),
         "int3\nnopl " +
             itostr(0x40 + (AccessInfo & HWASanAccessInfo::RuntimeMask)) +
             "(%rax)",
         "{rdi}",
         /*hasSideEffects=*/true);
     break;
   case Triple::aarch64:
   case Triple::aarch64_be:
     // The signal handler will find the data address in x0.
     Asm = InlineAsm::get(
-        FunctionType::get(VoidTy, {PtrLong->getType()}, false),
+        FunctionType::get(VoidTy, {TagCheck.PtrLong->getType()}, false),
         "brk #" + itostr(0x900 + (AccessInfo & HWASanAccessInfo::RuntimeMask)),
         "{x0}",
         /*hasSideEffects=*/true);
     break;
   case Triple::riscv64:
     // The signal handler will find the data address in x10.
     Asm = InlineAsm::get(
-        FunctionType::get(VoidTy, {PtrLong->getType()}, false),
+        FunctionType::get(VoidTy, {TagCheck.PtrLong->getType()}, false),
         "ebreak\naddiw x0, x11, " +
             itostr(0x40 + (AccessInfo & HWASanAccessInfo::RuntimeMask)),
         "{x10}",
         /*hasSideEffects=*/true);
     break;
   default:
     report_fatal_error("unsupported architecture");
   }
-  IRB.CreateCall(Asm, PtrLong);
+  IRB.CreateCall(Asm, TagCheck.PtrLong);
   if (Recover)
     cast<BranchInst>(CheckFailTerm)->setSuccessor(0, CheckTerm->getParent());
 }
 
 bool HWAddressSanitizer::ignoreMemIntrinsic(MemIntrinsic *MI) {
   if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) {
     return (!ClInstrumentWrites || ignoreAccess(MTI, MTI->getDest())) &&
            (!ClInstrumentReads || ignoreAccess(MTI, MTI->getSource()));