From e9d5f6e387bb56f3809a56fe8e41501a297cc14e Mon Sep 17 00:00:00 2001 From: Elena Demikhovsky Date: Tue, 11 Feb 2014 10:21:53 +0000 Subject: [PATCH] AVX: fixed a bug in LowerVECTOR_SHUFFLE git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201140 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86ISelLowering.cpp | 6 +++++- test/CodeGen/X86/avx-shuffle.ll | 9 +++++++++ 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index 32e41c36802..85656d80914 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -7371,7 +7371,11 @@ X86TargetLowering::LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG) const { if (V1IsUndef && V2IsUndef) return DAG.getUNDEF(VT); - assert(!V1IsUndef && "Op 1 of shuffle should not be undef"); + // When we create a shuffle node we put the UNDEF node to second operand, + // but in some cases the first operand may be transformed to UNDEF. + // In this case we should just commute the node. + if (V1IsUndef) + return CommuteVectorShuffle(SVOp, DAG); // Vector shuffle lowering takes 3 steps: // diff --git a/test/CodeGen/X86/avx-shuffle.ll b/test/CodeGen/X86/avx-shuffle.ll index 0956361c7e3..02aa617c56c 100644 --- a/test/CodeGen/X86/avx-shuffle.ll +++ b/test/CodeGen/X86/avx-shuffle.ll @@ -297,3 +297,12 @@ entry: } declare <2 x double> @llvm.x86.avx.vextractf128.pd.256(<4 x double>, i8) nounwind readnone declare <4 x double> @llvm.x86.avx.vinsertf128.pd.256(<4 x double>, <2 x double>, i8) nounwind readnone + +; this test case just should not fail +define void @test20() { + %a0 = insertelement <3 x double> , double 0.000000e+00, i32 2 + store <3 x double> %a0, <3 x double>* undef, align 1 + %a1 = insertelement <3 x double> , double undef, i32 2 + store <3 x double> %a1, <3 x double>* undef, align 1 + ret void +}