diff options
| -rw-r--r-- | lib/Transforms/Scalar/ScalarReplAggregates.cpp | 28 | ||||
| -rw-r--r-- | test/Transforms/ScalarRepl/2009-04-21-ZeroLengthMemSet.ll | 16 |
2 files changed, 31 insertions, 13 deletions
diff --git a/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/lib/Transforms/Scalar/ScalarReplAggregates.cpp index 9cbe073e29..1bc8a1e3ea 100644 --- a/lib/Transforms/Scalar/ScalarReplAggregates.cpp +++ b/lib/Transforms/Scalar/ScalarReplAggregates.cpp @@ -1431,20 +1431,22 @@ void SROA::ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, uint64_t Offset) { if (MemSetInst *MSI = dyn_cast<MemSetInst>(User)) { assert(MSI->getRawDest() == Ptr && "Consistency error!"); unsigned NumBytes = cast<ConstantInt>(MSI->getLength())->getZExtValue(); - unsigned Val = cast<ConstantInt>(MSI->getValue())->getZExtValue(); - - // Compute the value replicated the right number of times. - APInt APVal(NumBytes*8, Val); + if (NumBytes != 0) { + unsigned Val = cast<ConstantInt>(MSI->getValue())->getZExtValue(); + + // Compute the value replicated the right number of times. + APInt APVal(NumBytes*8, Val); - // Splat the value if non-zero. - if (Val) - for (unsigned i = 1; i != NumBytes; ++i) - APVal |= APVal << 8; - - Value *Old = Builder.CreateLoad(NewAI, (NewAI->getName()+".in").c_str()); - Value *New = ConvertScalar_InsertValue(ConstantInt::get(APVal), Old, - Offset, Builder); - Builder.CreateStore(New, NewAI); + // Splat the value if non-zero. + if (Val) + for (unsigned i = 1; i != NumBytes; ++i) + APVal |= APVal << 8; + + Value *Old = Builder.CreateLoad(NewAI, (NewAI->getName()+".in").c_str()); + Value *New = ConvertScalar_InsertValue(ConstantInt::get(APVal), Old, + Offset, Builder); + Builder.CreateStore(New, NewAI); + } MSI->eraseFromParent(); continue; } diff --git a/test/Transforms/ScalarRepl/2009-04-21-ZeroLengthMemSet.ll b/test/Transforms/ScalarRepl/2009-04-21-ZeroLengthMemSet.ll new file mode 100644 index 0000000000..2342f05aac --- /dev/null +++ b/test/Transforms/ScalarRepl/2009-04-21-ZeroLengthMemSet.ll @@ -0,0 +1,16 @@ +; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis +; rdar://6808691 +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128" +target triple = "x86_64-apple-darwin9.0" + type <{ i32, i16, i8, i8, i64, i64, i16, [0 x i16] }> + +define i32 @foo() { +entry: + %.compoundliteral = alloca %0 + %tmp228 = getelementptr %0* %.compoundliteral, i32 0, i32 7 + %tmp229 = bitcast [0 x i16]* %tmp228 to i8* + call void @llvm.memset.i64(i8* %tmp229, i8 0, i64 0, i32 2) + unreachable +} + +declare void @llvm.memset.i64(i8* nocapture, i8, i64, i32) nounwind |