[llvm] r207992 - Optimize shufflevector that copies an i64/f64 and zeros the rest.

[Filipe Cabecinhas]

Author: filcab
Date: Mon May  5 14:36:28 2014
New Revision: 207992

URL: http://llvm.org/viewvc/llvm-project?rev=207992&view=rev
Log:
Optimize shufflevector that copies an i64/f64 and zeros the rest.

Summary:
Also ran clang-format on the function. The code added is the last else
if block.

Reviewers: nadav, craig.topper

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D3518

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/avx-shuffle.ll
    llvm/trunk/test/CodeGen/X86/sse2.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=207992&r1=207991&r2=207992&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Mon May  5 14:36:28 2014
@@ -7468,9 +7468,8 @@ static SDValue LowerVectorIntExtend(SDVa
                      DAG.getNode(X86ISD::VZEXT, DL, NVT, V1));
 }
 
-static SDValue
-NormalizeVectorShuffle(SDValue Op, const X86Subtarget *Subtarget,
-                       SelectionDAG &DAG) {
+static SDValue NormalizeVectorShuffle(SDValue Op, const X86Subtarget *Subtarget,
+                                      SelectionDAG &DAG) {
   ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(Op);
   MVT VT = Op.getSimpleValueType();
   SDLoc dl(Op);
@@ -7495,33 +7494,43 @@ NormalizeVectorShuffle(SDValue Op, const
 
   // If the shuffle can be profitably rewritten as a narrower shuffle, then
   // do it!
-  if (VT == MVT::v8i16  || VT == MVT::v16i8 ||
-      VT == MVT::v16i16 || VT == MVT::v32i8) {
+  if (VT == MVT::v8i16 || VT == MVT::v16i8 || VT == MVT::v16i16 ||
+      VT == MVT::v32i8) {
     SDValue NewOp = RewriteAsNarrowerShuffle(SVOp, DAG);
     if (NewOp.getNode())
       return DAG.getNode(ISD::BITCAST, dl, VT, NewOp);
-  } else if ((VT == MVT::v4i32 ||
-             (VT == MVT::v4f32 && Subtarget->hasSSE2()))) {
+  } else if ((VT == MVT::v4i32 || (VT == MVT::v4f32 && Subtarget->hasSSE2()))) {
     // FIXME: Figure out a cleaner way to do this.
-    // Try to make use of movq to zero out the top part.
     if (ISD::isBuildVectorAllZeros(V2.getNode())) {
       SDValue NewOp = RewriteAsNarrowerShuffle(SVOp, DAG);
       if (NewOp.getNode()) {
         MVT NewVT = NewOp.getSimpleValueType();
         if (isCommutedMOVLMask(cast<ShuffleVectorSDNode>(NewOp)->getMask(),
                                NewVT, true, false))
-          return getVZextMovL(VT, NewVT, NewOp.getOperand(0),
-                              DAG, Subtarget, dl);
+          return getVZextMovL(VT, NewVT, NewOp.getOperand(0), DAG, Subtarget,
+                              dl);
       }
     } else if (ISD::isBuildVectorAllZeros(V1.getNode())) {
       SDValue NewOp = RewriteAsNarrowerShuffle(SVOp, DAG);
       if (NewOp.getNode()) {
         MVT NewVT = NewOp.getSimpleValueType();
         if (isMOVLMask(cast<ShuffleVectorSDNode>(NewOp)->getMask(), NewVT))
-          return getVZextMovL(VT, NewVT, NewOp.getOperand(1),
-                              DAG, Subtarget, dl);
+          return getVZextMovL(VT, NewVT, NewOp.getOperand(1), DAG, Subtarget,
+                              dl);
       }
     }
+  } else if ((VT == MVT::v2i64 || VT == MVT::v2f64) && Subtarget->hasSSE2()) {
+    // Emit movq and vmovq to copy an i64 or f64 to a vector and zero the
+    // other bits.
+    if (ISD::isBuildVectorAllZeros(V2.getNode())) {
+      MVT NewVT = SVOp->getSimpleValueType(0);
+      if (isCommutedMOVLMask(SVOp->getMask(), NewVT, true, false))
+        return getVZextMovL(VT, NewVT, SVOp->getOperand(0), DAG, Subtarget, dl);
+    } else if (ISD::isBuildVectorAllZeros(V1.getNode())) {
+      MVT NewVT = SVOp->getSimpleValueType(0);
+      if (isMOVLMask(SVOp->getMask(), NewVT))
+        return getVZextMovL(VT, NewVT, SVOp->getOperand(1), DAG, Subtarget, dl);
+    }
   }
   return SDValue();
 }

Modified: llvm/trunk/test/CodeGen/X86/avx-shuffle.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx-shuffle.ll?rev=207992&r1=207991&r2=207992&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/avx-shuffle.ll (original)
+++ llvm/trunk/test/CodeGen/X86/avx-shuffle.ll Mon May  5 14:36:28 2014
@@ -306,3 +306,11 @@ define void @test20() {
   store <3 x double> %a1, <3 x double>* undef, align 1
   ret void
 }
+
+define <2 x i64> @test_insert_64_zext(<2 x i64> %i) {
+; CHECK-LABEL: test_insert_64_zext
+; CHECK-NOT: xor
+; CHECK: vmovq
+  %1 = shufflevector <2 x i64> %i, <2 x i64> <i64 0, i64 undef>, <2 x i32> <i32 0, i32 2>
+  ret <2 x i64> %1
+}

Modified: llvm/trunk/test/CodeGen/X86/sse2.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/sse2.ll?rev=207992&r1=207991&r2=207992&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/sse2.ll (original)
+++ llvm/trunk/test/CodeGen/X86/sse2.ll Mon May  5 14:36:28 2014
@@ -221,3 +221,11 @@ entry:
  %double2float.i = fptrunc <4 x double> %0 to <4 x float>
  ret <4 x float> %double2float.i
 }
+
+define <2 x i64> @test_insert_64_zext(<2 x i64> %i) {
+; CHECK-LABEL: test_insert_64_zext
+; CHECK-NOT: xor
+; CHECK: movq
+  %1 = shufflevector <2 x i64> %i, <2 x i64> <i64 0, i64 undef>, <2 x i32> <i32 0, i32 2>
+  ret <2 x i64> %1
+}