[X86] Fix shuffle decoding for variable VPERMIL to be tolerant of the Constant type not matching due to folding in the constant pool and to get VPERMILPD correct.

llvm-svn: 256433

1 files changed, 8 insertions, 1 deletions

diff --git a/llvm/lib/Target/X86/X86MCInstLower.cpp b/llvm/lib/Target/X86/X86MCInstLower.cpp
index d0c03d6ab7c..74f31259866 100644
--- a/llvm/lib/Target/X86/X86MCInstLower.cpp
+++ b/llvm/lib/Target/X86/X86MCInstLower.cpp
@@ -1303,9 +1303,16 @@ void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
     const MachineOperand &SrcOp = MI->getOperand(1);
     const MachineOperand &MaskOp = MI->getOperand(5);
 
+    unsigned ElSize;
+    switch (MI->getOpcode()) {
+    default: llvm_unreachable("Invalid opcode");
+    case X86::VPERMILPSrm: case X86::VPERMILPSYrm: ElSize = 32; break;
+    case X86::VPERMILPDrm: case X86::VPERMILPDYrm: ElSize = 64; break;
+    }
+
     if (auto *C = getConstantFromPool(*MI, MaskOp)) {
       SmallVector<int, 16> Mask;
-      DecodeVPERMILPMask(C, Mask);
+      DecodeVPERMILPMask(C, ElSize, Mask);
       if (!Mask.empty())
         OutStreamer->AddComment(getShuffleComment(DstOp, SrcOp, Mask));
     }