From 5c683972bc6c5bd29bd25891b9f54d73d47bce10 Mon Sep 17 00:00:00 2001 From: Craig Topper Date: Mon, 28 Jan 2013 07:41:18 +0000 Subject: Fix 256-bit PALIGNR comment decoding to understand that it works on independent 256-bit lanes. llvm-svn: 173674 --- llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'llvm/lib/Target/X86/Utils') diff --git a/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp b/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp index b490f270254..bbd490411f2 100644 --- a/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp +++ b/llvm/lib/Target/X86/Utils/X86ShuffleDecode.cpp @@ -66,8 +66,17 @@ void DecodePALIGNRMask(MVT VT, unsigned Imm, unsigned NumElts = VT.getVectorNumElements(); unsigned Offset = Imm * (VT.getVectorElementType().getSizeInBits() / 8); - for (unsigned i = 0; i != NumElts; ++i) - ShuffleMask.push_back((i + Offset) % (NumElts * 2)); + unsigned NumLanes = VT.getSizeInBits() / 128; + unsigned NumLaneElts = NumElts / NumLanes; + + for (unsigned l = 0; l != NumElts; l += NumLaneElts) { + for (unsigned i = 0; i != NumLaneElts; ++i) { + unsigned Base = i + Offset; + // if i+offset is out of this lane then we actually need the other source + if (Base >= NumLaneElts) Base += NumElts - NumLaneElts; + ShuffleMask.push_back(Base + l); + } + } } /// DecodePSHUFMask - This decodes the shuffle masks for pshufd, and vpermilp*. -- cgit v1.2.3