Revert r164763 because it introduces new shuffles.

Thanks Nick Lewycky for pointing this out.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181177 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 2 insertions, 90 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineSelect.cpp b/lib/Transforms/InstCombine/InstCombineSelect.cpp
index 2defe631ae..59502fb988 100644
--- a/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -974,7 +974,7 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
     return &SI;
   }
 
-  if (VectorType *VecTy = dyn_cast<VectorType>(SI.getType())) {
+  if (VectorType* VecTy = dyn_cast<VectorType>(SI.getType())) {
     unsigned VWidth = VecTy->getNumElements();
     APInt UndefElts(VWidth, 0);
     APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
@@ -984,24 +984,6 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
       return &SI;
     }
 
-    if (ConstantVector *CV = dyn_cast<ConstantVector>(CondVal)) {
-      // Form a shufflevector instruction.
-      SmallVector<Constant *, 8> Mask(VWidth);
-      Type *Int32Ty = Type::getInt32Ty(CV->getContext());
-      for (unsigned i = 0; i != VWidth; ++i) {
-        Constant *Elem = cast<Constant>(CV->getOperand(i));
-        if (ConstantInt *E = dyn_cast<ConstantInt>(Elem))
-          Mask[i] = ConstantInt::get(Int32Ty, i + (E->isZero() ? VWidth : 0));
-        else if (isa<UndefValue>(Elem))
-          Mask[i] = UndefValue::get(Int32Ty);
-        else
-          return 0;
-      }
-      Constant *MaskVal = ConstantVector::get(Mask);
-      Value *V = Builder->CreateShuffleVector(TrueVal, FalseVal, MaskVal);
-      return ReplaceInstUsesWith(SI, V);
-    }
-
     if (isa<ConstantAggregateZero>(CondVal)) {
       return ReplaceInstUsesWith(SI, FalseVal);
     }
diff --git a/test/Transforms/InstCombine/vec_demanded_elts.ll b/test/Transforms/InstCombine/vec_demanded_elts.ll
index 2d90750a2f..0019a57627 100644
--- a/test/Transforms/InstCombine/vec_demanded_elts.ll
+++ b/test/Transforms/InstCombine/vec_demanded_elts.ll
@@ -196,7 +196,7 @@ define <4 x float> @test_select(float %f, float %g) {
 ; CHECK-NOT: insertelement
 ; CHECK: %a3 = insertelement <4 x float> %a0, float 3.000000e+00, i32 3
 ; CHECK-NOT: insertelement
-; CHECK: shufflevector <4 x float> %a3, <4 x float> <float undef, float 4.000000e+00, float 5.000000e+00, float undef>, <4 x i32> <i32 0, i32 5, i32 6, i32 3>
+; CHECK: %ret = select <4 x i1> <i1 true, i1 false, i1 false, i1 true>, <4 x float> %a3, <4 x float> <float undef, float 4.000000e+00, float 5.000000e+00, float undef>
   %a0 = insertelement <4 x float> undef, float %f, i32 0
   %a1 = insertelement <4 x float> %a0, float 1.000000e+00, i32 1
   %a2 = insertelement <4 x float> %a1, float 2.000000e+00, i32 2
diff --git a/test/Transforms/InstCombine/vec_shuffle.ll b/test/Transforms/InstCombine/vec_shuffle.ll
index 37d4d56e91..8f78c2e6bd 100644
--- a/test/Transforms/InstCombine/vec_shuffle.ll
+++ b/test/Transforms/InstCombine/vec_shuffle.ll
@@ -153,73 +153,3 @@ define <8 x i8> @test12a(<8 x i8> %tmp6, <8 x i8> %tmp2) nounwind {
   ret <8 x i8> %tmp3
 }
 
-; We should form a shuffle out of a select with constant condition.
-define <4 x i16> @test13a(<4 x i16> %lhs, <4 x i16> %rhs) {
-; CHECK: @test13a
-; CHECK-NEXT: shufflevector <4 x i16> %lhs, <4 x i16> %rhs, <4 x i32> <i32 0, i32 5, i32 2, i32 7>
-; CHECK-NEXT: ret
-  %A = select <4 x i1> <i1 true, i1 false, i1 true, i1 false>,
-           <4 x i16> %lhs, <4 x i16> %rhs
-  ret <4 x i16> %A
-}
-
-define <4 x i16> @test13b(<4 x i16> %lhs, <4 x i16> %rhs) {
-; CHECK: @test13b
-; CHECK-NEXT: ret <4 x i16> %lhs
-  %A = select <4 x i1> <i1 true, i1 undef, i1 true, i1 true>,
-           <4 x i16> %lhs, <4 x i16> %rhs
-  ret <4 x i16> %A
-}
-
-define <4 x i16> @test13c(<4 x i16> %lhs, <4 x i16> %rhs) {
-; CHECK: @test13c
-; CHECK-NEXT: shufflevector <4 x i16> %lhs, <4 x i16> %rhs, <4 x i32> <i32 0, i32 undef, i32 2, i32 7>
-; CHECK-NEXT: ret
-  %A = select <4 x i1> <i1 true, i1 undef, i1 true, i1 false>,
-           <4 x i16> %lhs, <4 x i16> %rhs
-  ret <4 x i16> %A
-}
-
-define <4 x i16> @test13d(<4 x i16> %lhs, <4 x i16> %rhs) {
-; CHECK: @test13d
-; CHECK: select
-; CHECK-NEXT: ret
-  %A = select <4 x i1> <i1 true, i1 icmp ugt (<4 x i16>(<4 x i16>, <4 x i16>)* @test13a, <4 x i16>(<4 x i16>, <4 x i16>)* @test13b), i1 true, i1 false>,
-           <4 x i16> %lhs, <4 x i16> %rhs
-  ret <4 x i16> %A
-}
-
-define <4 x i16> @test13e(<4 x i16> %lhs, <4 x i16> %rhs) {
-; CHECK: @test13e
-; CHECK-NEXT: ret <4 x i16> %rhs
-  %A = select <4 x i1> <i1 false, i1 false, i1 false, i1 false>,
-           <4 x i16> %lhs, <4 x i16> %rhs
-  ret <4 x i16> %A
-}
-
-; Check that sequences of insert/extract element are
-; collapsed into shuffle instruction with correct shuffle indexes.
-
-define <4 x float> @test14a(<4 x float> %LHS, <4 x float> %RHS) {
-; CHECK: @test14a
-; CHECK-NEXT: shufflevector <4 x float> %LHS, <4 x float> %RHS, <4 x i32> <i32 4, i32 0, i32 6, i32 6>
-; CHECK-NEXT: ret <4 x float> %tmp4
-        %tmp1 = extractelement <4 x float> %LHS, i32 0
-        %tmp2 = insertelement <4 x float> %RHS, float %tmp1, i32 1
-        %tmp3 = extractelement <4 x float> %RHS, i32 2
-        %tmp4 = insertelement <4 x float> %tmp2, float %tmp3, i32 3
-        ret <4 x float> %tmp4
-}
-
-define <4 x float> @test14b(<4 x float> %LHS, <4 x float> %RHS) {
-; CHECK: @test14b
-; CHECK-NEXT: shufflevector <4 x float> %LHS, <4 x float> %RHS, <4 x i32> <i32 4, i32 3, i32 6, i32 6>
-; CHECK-NEXT: ret <4 x float> %tmp5
-        %tmp0 = extractelement <4 x float> %LHS, i32 3
-        %tmp1 = insertelement <4 x float> %RHS, float %tmp0, i32 0
-        %tmp2 = extractelement <4 x float> %tmp1, i32 0
-        %tmp3 = insertelement <4 x float> %RHS, float %tmp2, i32 1
-        %tmp4 = extractelement <4 x float> %RHS, i32 2
-        %tmp5 = insertelement <4 x float> %tmp3, float %tmp4, i32 3
-        ret <4 x float> %tmp5
-}