From 75504d45ec5b1c3c19b3db9ab7efe29d3d1ac1e9 Mon Sep 17 00:00:00 2001 From: Chandler Carruth Date: Fri, 27 Jun 2014 18:25:23 +0000 Subject: [x86] Fix a miscompile in the new shuffle lowering uncovered by a bootstrap. I managed to mis-remember how PACKUS worked on x86, and was using undef for the high bytes instead of zero. The fix is fairly obvious. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211922 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/X86/X86ISelLowering.cpp | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) (limited to 'lib') diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index c50f44daae..fa80717f99 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -7712,19 +7712,19 @@ static SDValue lowerV16I8VectorShuffle(SDValue Op, SDValue V1, SDValue V2, return DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, Evens, Odds); } - - SDValue LoV1 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, - DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V1, - DAG.getUNDEF(MVT::v8i16))); - SDValue HiV1 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, - DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V1, - DAG.getUNDEF(MVT::v8i16))); - SDValue LoV2 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, - DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V2, - DAG.getUNDEF(MVT::v8i16))); - SDValue HiV2 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, - DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V2, - DAG.getUNDEF(MVT::v8i16))); + SDValue Zero = getZeroVector(MVT::v8i16, Subtarget, DAG, DL); + SDValue LoV1 = + DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, + DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V1, Zero)); + SDValue HiV1 = + DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, + DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V1, Zero)); + SDValue LoV2 = + DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, + DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V2, Zero)); + SDValue HiV2 = + DAG.getNode(ISD::BITCAST, DL, MVT::v8i16, + DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V2, Zero)); int V1LoBlendMask[8] = {-1, -1, -1, -1, -1, -1, -1, -1}; int V1HiBlendMask[8] = {-1, -1, -1, -1, -1, -1, -1, -1}; -- cgit v1.2.3