[x86] Teach the x86 DAG combiner to form MOVSLDUP and MOVSHDUP

instructions when it finds an appropriate pattern.

These are lovely instructions, and its a shame to not use them. =] They
are fast, and can hand loads folded into their operands, etc.

I've also plumbed the comment shuffle decoding through the various
layers so that the test cases are printed nicely.

llvm-svn: 217758

1 files changed, 36 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/InstPrinter/X86InstComments.cpp b/llvm/lib/Target/X86/InstPrinter/X86InstComments.cpp
index 5deb6825148..cb120633a40 100644
--- a/llvm/lib/Target/X86/InstPrinter/X86InstComments.cpp
+++ b/llvm/lib/Target/X86/InstPrinter/X86InstComments.cpp
@@ -128,6 +128,42 @@ bool llvm::EmitAnyX86InstComments(const MCInst *MI, raw_ostream &OS,
     DecodeMOVHLPSMask(2, ShuffleMask);
     break;
 
+  case X86::MOVSLDUPrr:
+  case X86::VMOVSLDUPrr:
+    Src1Name = getRegName(MI->getOperand(1).getReg());
+    // FALL THROUGH.
+  case X86::MOVSLDUPrm:
+  case X86::VMOVSLDUPrm:
+    DestName = getRegName(MI->getOperand(0).getReg());
+    DecodeMOVSLDUPMask(MVT::v4f32, ShuffleMask);
+    break;
+
+  case X86::VMOVSHDUPYrr:
+    Src1Name = getRegName(MI->getOperand(1).getReg());
+    // FALL THROUGH.
+  case X86::VMOVSHDUPYrm:
+    DestName = getRegName(MI->getOperand(0).getReg());
+    DecodeMOVSHDUPMask(MVT::v8f32, ShuffleMask);
+    break;
+
+  case X86::VMOVSLDUPYrr:
+    Src1Name = getRegName(MI->getOperand(1).getReg());
+    // FALL THROUGH.
+  case X86::VMOVSLDUPYrm:
+    DestName = getRegName(MI->getOperand(0).getReg());
+    DecodeMOVSLDUPMask(MVT::v8f32, ShuffleMask);
+    break;
+
+  case X86::MOVSHDUPrr:
+  case X86::VMOVSHDUPrr:
+    Src1Name = getRegName(MI->getOperand(1).getReg());
+    // FALL THROUGH.
+  case X86::MOVSHDUPrm:
+  case X86::VMOVSHDUPrm:
+    DestName = getRegName(MI->getOperand(0).getReg());
+    DecodeMOVSHDUPMask(MVT::v4f32, ShuffleMask);
+    break;
+
   case X86::PALIGNR128rr:
   case X86::VPALIGNR128rr:
     Src1Name = getRegName(MI->getOperand(2).getReg());