From 3a9c51f2561fb5a8a27b560c3fa61cec8f334824 Mon Sep 17 00:00:00 2001
From: Nate Begeman <natebegeman@mac.com>
Date: Thu, 3 Dec 2009 07:11:29 +0000
Subject: [PATCH] Don't pull vector sext through both hands of a logical
 operation, since doing so prevents the fusion of vector sext and setcc into
 vsetcc. Add a testcase for the above transformation. Fix a bogus use of APInt
 noticed while tracking this down.

llvm-svn: 90423
---
 lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 10 ++++++--
 test/CodeGen/X86/vec_compare-2.ll        | 29 ++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)
 create mode 100644 test/CodeGen/X86/vec_compare-2.ll

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 64331b0fe26..204cbc4dc14 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -1688,10 +1688,14 @@ SDValue DAGCombiner::SimplifyBinOpWithSameOpcodeHands(SDNode *N) {
   // fold (OP (sext x), (sext y)) -> (sext (OP x, y))
   // fold (OP (aext x), (aext y)) -> (aext (OP x, y))
   // fold (OP (trunc x), (trunc y)) -> (trunc (OP x, y)) (if trunc isn't free)
+  //
+  // do not sink logical op inside of a vector extend, since it may combine
+  // into a vsetcc.
   if ((N0.getOpcode() == ISD::ZERO_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND||
        N0.getOpcode() == ISD::SIGN_EXTEND ||
        (N0.getOpcode() == ISD::TRUNCATE &&
         !TLI.isTruncateFree(N0.getOperand(0).getValueType(), VT))) &&
+      !VT.isVector() &&
       N0.getOperand(0).getValueType() == N1.getOperand(0).getValueType() &&
       (!LegalOperations ||
        TLI.isOperationLegal(N->getOpcode(), N0.getOperand(0).getValueType()))) {
@@ -1944,8 +1948,10 @@ SDValue DAGCombiner::visitOR(SDNode *N) {
   }
 
   // fold (or x, undef) -> -1
-  if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
-    return DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()), VT);
+  if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF) {
+    EVT EltVT = VT.isVector() ? VT.getVectorElementType() : VT;
+    return DAG.getConstant(APInt::getAllOnesValue(EltVT.getSizeInBits()), VT);
+  }
   // fold (or c1, c2) -> c1|c2
   if (N0C && N1C)
     return DAG.FoldConstantArithmetic(ISD::OR, VT, N0C, N1C);
diff --git a/test/CodeGen/X86/vec_compare-2.ll b/test/CodeGen/X86/vec_compare-2.ll
new file mode 100644
index 00000000000..091641b3bc3
--- /dev/null
+++ b/test/CodeGen/X86/vec_compare-2.ll
@@ -0,0 +1,29 @@
+; RUN: llc < %s -march=x86 -mcpu=penryn -disable-mmx | FileCheck %s
+
+declare <4 x float> @llvm.x86.sse41.blendvps(<4 x float>, <4 x float>, <4 x float>) nounwind readnone
+
+declare <8 x i16> @llvm.x86.sse41.packusdw(<4 x i32>, <4 x i32>) nounwind readnone
+
+declare <4 x i32> @llvm.x86.sse41.pmaxsd(<4 x i32>, <4 x i32>) nounwind readnone
+
+define void @blackDespeckle_wrapper(i8** %args_list, i64* %gtid, i64 %xend) {
+entry:
+; CHECK-NOT: set
+; CHECK: pcmpgt
+; CHECK: blendvps
+  %shr.i = ashr <4 x i32> zeroinitializer, <i32 3, i32 3, i32 3, i32 3> ; <<4 x i32>> [#uses=1]
+  %cmp318.i = sext <4 x i1> zeroinitializer to <4 x i32> ; <<4 x i32>> [#uses=1]
+  %sub322.i = sub <4 x i32> %shr.i, zeroinitializer ; <<4 x i32>> [#uses=1]
+  %cmp323.x = icmp slt <4 x i32> zeroinitializer, %sub322.i ; <<4 x i1>> [#uses=1]
+  %cmp323.i = sext <4 x i1> %cmp323.x to <4 x i32> ; <<4 x i32>> [#uses=1]
+  %or.i = or <4 x i32> %cmp318.i, %cmp323.i       ; <<4 x i32>> [#uses=1]
+  %tmp10.i83.i = bitcast <4 x i32> %or.i to <4 x float> ; <<4 x float>> [#uses=1]
+  %0 = call <4 x float> @llvm.x86.sse41.blendvps(<4 x float> undef, <4 x float> undef, <4 x float> %tmp10.i83.i) nounwind ; <<4 x float>> [#uses=1]
+  %conv.i.i15.i = bitcast <4 x float> %0 to <4 x i32> ; <<4 x i32>> [#uses=1]
+  %swz.i.i28.i = shufflevector <4 x i32> %conv.i.i15.i, <4 x i32> undef, <2 x i32> <i32 0, i32 1> ; <<2 x i32>> [#uses=1]
+  %tmp6.i29.i = bitcast <2 x i32> %swz.i.i28.i to <4 x i16> ; <<4 x i16>> [#uses=1]
+  %swz.i30.i = shufflevector <4 x i16> %tmp6.i29.i, <4 x i16> undef, <2 x i32> <i32 0, i32 1> ; <<2 x i16>> [#uses=1]
+  store <2 x i16> %swz.i30.i, <2 x i16>* undef
+  unreachable
+  ret void
+}