commit 94c81ca8e196e9b43280f0976ee4269c97f3084b
author Kostya Serebryany <kcc@google.com> Mon Apr 21 11:50:42 2014 +0000
committer Kostya Serebryany <kcc@google.com> Mon Apr 21 11:50:42 2014 +0000
tree 7f5ab0d2464f7c25bdd98b41afbe9ce384897b0b
parent 572e3407c37103c436d3236d5628091032e926e7

[asan] instead of inserting inline instrumentation around memset/memcpy/memmove, replace the intrinsic with __asan_memset/etc. This makes the memset/etc handling more complete and consistent with what we do in msan. It may slowdown some cases (when the intrinsic was actually inlined) and speedup other cases (when it was not inlined)

llvm-svn: 206746

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 5194f759..5cd34b0 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -141,8 +141,6 @@
        cl::Hidden, cl::init(1500));
 static cl::opt<bool> ClInitializers("asan-initialization-order",
        cl::desc("Handle C++ initializer order"), cl::Hidden, cl::init(false));
-static cl::opt<bool> ClMemIntrin("asan-memintrin",
-       cl::desc("Handle memset/memcpy/memmove"), cl::Hidden, cl::init(true));
 static cl::opt<bool> ClInvalidPointerPairs("asan-detect-invalid-pointer-pair",
        cl::desc("Instrument <, <=, >, >=, - with pointer operands"),
        cl::Hidden, cl::init(false));
@@ -327,7 +325,7 @@
   Instruction *generateCrashCode(Instruction *InsertBefore, Value *Addr,
                                  bool IsWrite, size_t AccessSizeIndex,
                                  Value *SizeArgument);
-  bool instrumentMemIntrinsic(MemIntrinsic *MI, bool UseCalls);
+  void instrumentMemIntrinsic(MemIntrinsic *MI);
   void instrumentMemIntrinsicParam(Instruction *OrigIns, Value *Addr,
                                    Value *Size, Instruction *InsertBefore,
                                    bool IsWrite, bool UseCalls);
@@ -367,6 +365,7 @@
   // This array is indexed by AccessIsWrite.
   Function *AsanErrorCallbackSized[2],
            *AsanMemoryAccessCallbackSized[2];
+  Function *AsanMemmove, *AsanMemcpy, *AsanMemset;
   InlineAsm *EmptyAsm;
   SetOfDynamicallyInitializedGlobals DynamicallyInitializedGlobals;
 
@@ -623,29 +622,24 @@
 }
 
 // Instrument memset/memmove/memcpy
-bool AddressSanitizer::instrumentMemIntrinsic(MemIntrinsic *MI, bool UseCalls) {
-  Value *Dst = MI->getDest();
-  MemTransferInst *MemTran = dyn_cast<MemTransferInst>(MI);
-  Value *Src = MemTran ? MemTran->getSource() : 0;
-  Value *Length = MI->getLength();
-
-  Constant *ConstLength = dyn_cast<Constant>(Length);
-  Instruction *InsertBefore = MI;
-  if (ConstLength) {
-    if (ConstLength->isNullValue()) return false;
-  } else {
-    // The size is not a constant so it could be zero -- check at run-time.
-    IRBuilder<> IRB(InsertBefore);
-
-    Value *Cmp = IRB.CreateICmpNE(Length,
-                                  Constant::getNullValue(Length->getType()));
-    InsertBefore = SplitBlockAndInsertIfThen(Cmp, InsertBefore, false);
+void AddressSanitizer::instrumentMemIntrinsic(MemIntrinsic *MI) {
+  IRBuilder<> IRB(MI);
+  Instruction *Call = 0;
+  if (isa<MemTransferInst>(MI)) {
+    Call = IRB.CreateCall3(
+        isa<MemMoveInst>(MI) ? AsanMemmove : AsanMemcpy,
+        IRB.CreatePointerCast(MI->getOperand(0), IRB.getInt8PtrTy()),
+        IRB.CreatePointerCast(MI->getOperand(1), IRB.getInt8PtrTy()),
+        IRB.CreateIntCast(MI->getOperand(2), IntptrTy, false));
+  } else if (isa<MemSetInst>(MI)) {
+    Call = IRB.CreateCall3(
+        AsanMemset,
+        IRB.CreatePointerCast(MI->getOperand(0), IRB.getInt8PtrTy()),
+        IRB.CreateIntCast(MI->getOperand(1), IRB.getInt32Ty(), false),
+        IRB.CreateIntCast(MI->getOperand(2), IntptrTy, false));
   }
-
-  instrumentMemIntrinsicParam(MI, Dst, Length, InsertBefore, true, UseCalls);
-  if (Src)
-    instrumentMemIntrinsicParam(MI, Src, Length, InsertBefore, false, UseCalls);
-  return true;
+  Call->setDebugLoc(MI->getDebugLoc());
+  MI->eraseFromParent();
 }
 
 // If I is an interesting memory access, return the PointerOperand
@@ -1156,8 +1150,18 @@
       M.getOrInsertFunction(ClMemoryAccessCallbackPrefix + "storeN",
                             IRB.getVoidTy(), IntptrTy, IntptrTy, NULL));
 
-  AsanHandleNoReturnFunc = checkInterfaceFunction(M.getOrInsertFunction(
-      kAsanHandleNoReturnName, IRB.getVoidTy(), NULL));
+  AsanMemmove = checkInterfaceFunction(M.getOrInsertFunction(
+      ClMemoryAccessCallbackPrefix + "memmove", IRB.getInt8PtrTy(),
+      IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IntptrTy, NULL));
+  AsanMemcpy = checkInterfaceFunction(M.getOrInsertFunction(
+      ClMemoryAccessCallbackPrefix + "memcpy", IRB.getInt8PtrTy(),
+      IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IntptrTy, NULL));
+  AsanMemset = checkInterfaceFunction(M.getOrInsertFunction(
+      ClMemoryAccessCallbackPrefix + "memset", IRB.getInt8PtrTy(),
+      IRB.getInt8PtrTy(), IRB.getInt32Ty(), IntptrTy, NULL));
+
+  AsanHandleNoReturnFunc = checkInterfaceFunction(
+      M.getOrInsertFunction(kAsanHandleNoReturnName, IRB.getVoidTy(), NULL));
   AsanCovFunction = checkInterfaceFunction(M.getOrInsertFunction(
       kAsanCovName, IRB.getVoidTy(), NULL));
   AsanPtrCmpFunction = checkInterfaceFunction(M.getOrInsertFunction(
@@ -1328,7 +1332,7 @@
                  isInterestingPointerComparisonOrSubtraction(BI)) {
         PointerComparisonsOrSubtracts.push_back(BI);
         continue;
-      } else if (isa<MemIntrinsic>(BI) && ClMemIntrin) {
+      } else if (isa<MemIntrinsic>(BI)) {
         // ok, take it.
       } else {
         if (isa<AllocaInst>(BI))
@@ -1374,7 +1378,7 @@
       if (isInterestingMemoryAccess(Inst, &IsWrite))
         instrumentMop(Inst, UseCalls);
       else
-        instrumentMemIntrinsic(cast<MemIntrinsic>(Inst), UseCalls);
+        instrumentMemIntrinsic(cast<MemIntrinsic>(Inst));
     }
     NumInstrumented++;
   }