[X86][XOP] Support for VPPERM 2-input shuffle mask decoding

This patch adds support for decoding XOP VPPERM instruction when it represents a basic shuffle.

The mask decoding required the existing MCInstrLowering code to be updated to support binary shuffles - the implementation now matches what is done in X86InstrComments.cpp.

Differential Revision: http://reviews.llvm.org/D18441

llvm-svn: 265874

1 files changed, 3 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/X86ShuffleDecodeConstantPool.h b/llvm/lib/Target/X86/X86ShuffleDecodeConstantPool.h
index bd61e4ba2e8..a07b26c04f7 100644
--- a/llvm/lib/Target/X86/X86ShuffleDecodeConstantPool.h
+++ b/llvm/lib/Target/X86/X86ShuffleDecodeConstantPool.h
@@ -32,6 +32,9 @@ void DecodePSHUFBMask(const Constant *C, SmallVectorImpl<int> &ShuffleMask);
 void DecodeVPERMILPMask(const Constant *C, unsigned ElSize,
                         SmallVectorImpl<int> &ShuffleMask);
 
+/// Decode a VPPERM variable mask from an IR-level vector constant.
+void DecodeVPPERMMask(const Constant *C, SmallVectorImpl<int> &ShuffleMask);
+
 /// Decode a VPERM W/D/Q/PS/PD mask from an IR-level vector constant.
 void DecodeVPERMVMask(const Constant *C, MVT VT,
                       SmallVectorImpl<int> &ShuffleMask);