From 41b33f437f70dcf63e35d08e5f4202258ef05c15 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Mon, 1 Jun 2009 09:14:32 +0000 Subject: [PATCH] PR4286: Make RewriteLoadUserOfWholeAlloca and RewriteStoreUserOfWholeAlloca deal with tail padding because isSafeUseOfBitCastedAllocation expects them to. Otherwise, we crash trying to erase the bitcast. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72688 91177308-0d34-0410-b5e6-96231b3b80d8 --- .../Scalar/ScalarReplAggregates.cpp | 21 ++++++++++++------- .../2009-06-01-BitcastIntPadding.ll | 17 +++++++++++++++ 2 files changed, 30 insertions(+), 8 deletions(-) create mode 100644 test/Transforms/ScalarRepl/2009-06-01-BitcastIntPadding.ll diff --git a/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/lib/Transforms/Scalar/ScalarReplAggregates.cpp index 5e2859abae4..9935f12f893 100644 --- a/lib/Transforms/Scalar/ScalarReplAggregates.cpp +++ b/lib/Transforms/Scalar/ScalarReplAggregates.cpp @@ -903,11 +903,13 @@ void SROA::RewriteStoreUserOfWholeAlloca(StoreInst *SI, // If this isn't a store of an integer to the whole alloca, it may be a store // to the first element. Just ignore the store in this case and normal SROA - // will handle it. We don't handle types here that have tail padding, like - // an alloca of type {i1}. + // will handle it. if (!isa(SrcVal->getType()) || - TD->getTypeSizeInBits(SrcVal->getType()) != AllocaSizeBits) + TD->getTypeAllocSizeInBits(SrcVal->getType()) != AllocaSizeBits) return; + // Handle tail padding by extending the operand + if (TD->getTypeSizeInBits(SrcVal->getType()) != AllocaSizeBits) + SrcVal = new ZExtInst(SrcVal, IntegerType::get(AllocaSizeBits), "", SI); DOUT << "PROMOTING STORE TO WHOLE ALLOCA: " << *AI << *SI; @@ -1016,10 +1018,9 @@ void SROA::RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocationInst *AI, // If this isn't a load of the whole alloca to an integer, it may be a load // of the first element. Just ignore the load in this case and normal SROA - // will handle it. We don't handle types here that have tail padding, like - // an alloca of type {i1}. + // will handle it. if (!isa(LI->getType()) || - TD->getTypeSizeInBits(LI->getType()) != AllocaSizeBits) + TD->getTypeAllocSizeInBits(LI->getType()) != AllocaSizeBits) return; DOUT << "PROMOTING LOAD OF WHOLE ALLOCA: " << *AI << *LI; @@ -1035,7 +1036,7 @@ void SROA::RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocationInst *AI, ArrayEltBitOffset = TD->getTypeAllocSizeInBits(ArrayEltTy); } - Value *ResultVal = Constant::getNullValue(LI->getType()); + Value *ResultVal = Constant::getNullValue(IntegerType::get(AllocaSizeBits)); for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { // Load the value from the alloca. If the NewElt is an aggregate, cast @@ -1082,7 +1083,11 @@ void SROA::RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocationInst *AI, ResultVal = BinaryOperator::CreateOr(SrcField, ResultVal, "", LI); } - + + // Handle tail padding by truncating the result + if (TD->getTypeSizeInBits(LI->getType()) != AllocaSizeBits) + ResultVal = new TruncInst(ResultVal, LI->getType(), "", LI); + LI->replaceAllUsesWith(ResultVal); LI->eraseFromParent(); } diff --git a/test/Transforms/ScalarRepl/2009-06-01-BitcastIntPadding.ll b/test/Transforms/ScalarRepl/2009-06-01-BitcastIntPadding.ll new file mode 100644 index 00000000000..ffdd679355a --- /dev/null +++ b/test/Transforms/ScalarRepl/2009-06-01-BitcastIntPadding.ll @@ -0,0 +1,17 @@ +; RUN: llvm-as < %s | opt -scalarrepl +; PR4286 + +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-undermydesk-freebsd8.0" + %struct.singlebool = type <{ i8 }> + +define zeroext i8 @doit() nounwind { +entry: + %a = alloca %struct.singlebool, align 1 ; <%struct.singlebool*> [#uses=2] + %storetmp.i = bitcast %struct.singlebool* %a to i1* ; [#uses=1] + store i1 true, i1* %storetmp.i + %tmp = getelementptr %struct.singlebool* %a, i64 0, i32 0 ; [#uses=1] + %tmp1 = load i8* %tmp ; [#uses=1] + ret i8 %tmp1 +} +