[llvm] r356067 - [X86][AVX] Add X86ISD::VTRUNC handling to SimplifyDemandedVectorEltsForTargetNode

[Simon Pilgrim via llvm-commits]

Author: rksimon
Date: Wed Mar 13 10:00:18 2019
New Revision: 356067

URL: http://llvm.org/viewvc/llvm-project?rev=356067&view=rev
Log:
[X86][AVX] Add X86ISD::VTRUNC handling to SimplifyDemandedVectorEltsForTargetNode

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/shuffle-vs-trunc-256-widen.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=356067&r1=356066&r2=356067&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Wed Mar 13 10:00:18 2019
@@ -33039,6 +33039,20 @@ bool X86TargetLowering::SimplifyDemanded
       return true;
     break;
   }
+  case X86ISD::VTRUNC:
+  case X86ISD::VTRUNCS:
+  case X86ISD::VTRUNCUS: {
+    SDValue Src = Op.getOperand(0);
+    MVT SrcVT = Src.getSimpleValueType();
+    APInt DemandedSrc = DemandedElts.zextOrTrunc(SrcVT.getVectorNumElements());
+    APInt SrcUndef, SrcZero;
+    if (SimplifyDemandedVectorElts(Src, DemandedSrc, SrcUndef, SrcZero, TLO,
+                                   Depth + 1))
+      return true;
+    KnownZero = SrcZero.zextOrTrunc(NumElts);
+    KnownUndef = SrcUndef.zextOrTrunc(NumElts);
+    break;
+  }
   case X86ISD::BLENDV: {
     APInt SelUndef, SelZero;
     if (SimplifyDemandedVectorElts(Op.getOperand(0), DemandedElts, SelUndef,

Modified: llvm/trunk/test/CodeGen/X86/shuffle-vs-trunc-256-widen.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/shuffle-vs-trunc-256-widen.ll?rev=356067&r1=356066&r2=356067&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/shuffle-vs-trunc-256-widen.ll (original)
+++ llvm/trunk/test/CodeGen/X86/shuffle-vs-trunc-256-widen.ll Wed Mar 13 10:00:18 2019
@@ -1179,7 +1179,7 @@ define void @trunc_v4i64_to_v4i8(<32 x i
 ;
 ; AVX512F-LABEL: trunc_v4i64_to_v4i8:
 ; AVX512F:       # %bb.0:
-; AVX512F-NEXT:    vbroadcasti64x4 {{.*#+}} zmm0 = mem[0,1,2,3,0,1,2,3]
+; AVX512F-NEXT:    vmovdqa (%rdi), %ymm0
 ; AVX512F-NEXT:    vpmovqb %zmm0, %xmm0
 ; AVX512F-NEXT:    vmovd %xmm0, (%rsi)
 ; AVX512F-NEXT:    vzeroupper
@@ -1194,7 +1194,7 @@ define void @trunc_v4i64_to_v4i8(<32 x i
 ;
 ; AVX512BW-LABEL: trunc_v4i64_to_v4i8:
 ; AVX512BW:       # %bb.0:
-; AVX512BW-NEXT:    vbroadcasti64x4 {{.*#+}} zmm0 = mem[0,1,2,3,0,1,2,3]
+; AVX512BW-NEXT:    vmovdqa (%rdi), %ymm0
 ; AVX512BW-NEXT:    vpmovqb %zmm0, %xmm0
 ; AVX512BW-NEXT:    vmovd %xmm0, (%rsi)
 ; AVX512BW-NEXT:    vzeroupper