[llvm] r345824 - [X86][SSE] Move 2-input limit up from getFauxShuffleMask to resolveTargetShuffleInputs (reapplied)

[Simon Pilgrim via llvm-commits]

Author: rksimon
Date: Thu Nov  1 04:52:09 2018
New Revision: 345824

URL: http://llvm.org/viewvc/llvm-project?rev=345824&view=rev
Log:
[X86][SSE] Move 2-input limit up from getFauxShuffleMask to resolveTargetShuffleInputs (reapplied)

Reapplying an updated version of rL345395 (reverted in rL345451), now the issues noticed in PR39483 have been fixed. 

This patch allows resolveTargetShuffleInputs to remove UNDEF inputs from cases where we have more than 2 inputs.

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/avx512-shuffles/partial_permute.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=345824&r1=345823&r2=345824&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Thu Nov  1 04:52:09 2018
@@ -6325,9 +6325,6 @@ static bool getFauxShuffleMask(SDValue N
     if (!resolveTargetShuffleInputs(N0, SrcInputs0, SrcMask0, DAG) ||
         !resolveTargetShuffleInputs(N1, SrcInputs1, SrcMask1, DAG))
       return false;
-    // TODO - Add support for more than 2 inputs.
-    if ((SrcInputs0.size() + SrcInputs1.size()) > 2)
-      return false;
     int MaskSize = std::max(SrcMask0.size(), SrcMask1.size());
     SmallVector<int, 64> Mask0, Mask1;
     scaleShuffleMask<int>(MaskSize / SrcMask0.size(), SrcMask0, Mask0);
@@ -6386,8 +6383,7 @@ static bool getFauxShuffleMask(SDValue N
       }
       Mask[i + InsertIdx] = M;
     }
-    // TODO - Add support for more than 1 subinput.
-    return Ops.size() <= 2;
+    return true;
   }
   case ISD::SCALAR_TO_VECTOR: {
     // Match against a scalar_to_vector of an extract from a vector,
@@ -6580,7 +6576,8 @@ static bool resolveTargetShuffleInputs(S
       return false;
 
   resolveTargetShuffleInputsAndMask(Inputs, Mask);
-  return true;
+  // TODO - Add support for more than 2 inputs.
+  return Inputs.size() <= 2;
 }
 
 /// Returns the scalar element that will make up the ith

Modified: llvm/trunk/test/CodeGen/X86/avx512-shuffles/partial_permute.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx512-shuffles/partial_permute.ll?rev=345824&r1=345823&r2=345824&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/avx512-shuffles/partial_permute.ll (original)
+++ llvm/trunk/test/CodeGen/X86/avx512-shuffles/partial_permute.ll Thu Nov  1 04:52:09 2018
@@ -4019,11 +4019,11 @@ define <4 x double> @test_masked_8xdoubl
 ; CHECK-LABEL: test_masked_8xdouble_to_4xdouble_perm_mask4:
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    vextractf64x4 $1, %zmm0, %ymm3
-; CHECK-NEXT:    vunpckhpd {{.*#+}} xmm0 = xmm0[1],xmm3[1]
-; CHECK-NEXT:    vxorpd %xmm3, %xmm3, %xmm3
-; CHECK-NEXT:    vcmpeqpd %ymm3, %ymm2, %k1
-; CHECK-NEXT:    vpermpd {{.*#+}} ymm1 {%k1} = ymm0[0,0,1,1]
-; CHECK-NEXT:    vmovapd %ymm1, %ymm0
+; CHECK-NEXT:    vmovapd {{.*#+}} ymm4 = [1,1,5,5]
+; CHECK-NEXT:    vpermi2pd %ymm3, %ymm0, %ymm4
+; CHECK-NEXT:    vxorpd %xmm0, %xmm0, %xmm0
+; CHECK-NEXT:    vcmpeqpd %ymm0, %ymm2, %k1
+; CHECK-NEXT:    vblendmpd %ymm4, %ymm1, %ymm0 {%k1}
 ; CHECK-NEXT:    retq
   %shuf = shufflevector <8 x double> %vec, <8 x double> undef, <4 x i32> <i32 1, i32 1, i32 5, i32 5>
   %cmp = fcmp oeq <4 x double> %mask, zeroinitializer
@@ -4034,11 +4034,12 @@ define <4 x double> @test_masked_8xdoubl
 define <4 x double> @test_masked_z_8xdouble_to_4xdouble_perm_mask4(<8 x double> %vec, <4 x double> %mask) {
 ; CHECK-LABEL: test_masked_z_8xdouble_to_4xdouble_perm_mask4:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vextractf64x4 $1, %zmm0, %ymm2
-; CHECK-NEXT:    vunpckhpd {{.*#+}} xmm0 = xmm0[1],xmm2[1]
-; CHECK-NEXT:    vxorpd %xmm2, %xmm2, %xmm2
-; CHECK-NEXT:    vcmpeqpd %ymm2, %ymm1, %k1
-; CHECK-NEXT:    vpermpd {{.*#+}} ymm0 {%k1} {z} = ymm0[0,0,1,1]
+; CHECK-NEXT:    vextractf64x4 $1, %zmm0, %ymm3
+; CHECK-NEXT:    vmovapd {{.*#+}} ymm2 = [1,1,5,5]
+; CHECK-NEXT:    vxorpd %xmm4, %xmm4, %xmm4
+; CHECK-NEXT:    vcmpeqpd %ymm4, %ymm1, %k1
+; CHECK-NEXT:    vpermi2pd %ymm3, %ymm0, %ymm2 {%k1} {z}
+; CHECK-NEXT:    vmovapd %ymm2, %ymm0
 ; CHECK-NEXT:    retq
   %shuf = shufflevector <8 x double> %vec, <8 x double> undef, <4 x i32> <i32 1, i32 1, i32 5, i32 5>
   %cmp = fcmp oeq <4 x double> %mask, zeroinitializer