Remove Instruction check difference

Author: davemgreen

llvm/lib/Transforms/Vectorize/VectorCombine.cpp

@@ -1746,7 +1746,7 @@ static Value *generateNewInstTree(ArrayRef<InstLane> Item, FixedVectorType *Ty,
     return Builder.CreateCmp(CI->getPredicate(), Ops[0], Ops[1]);
   if (auto *SI = dyn_cast<SelectInst>(I))
     return Builder.CreateSelect(Ops[0], Ops[1], Ops[2], "", SI);
-  if (auto CI = dyn_cast<CastInst>(I))
+  if (auto *CI = dyn_cast<CastInst>(I))
     return Builder.CreateCast((Instruction::CastOps)CI->getOpcode(), Ops[0],
                               DstTy);
   if (II)
@@ -1760,7 +1760,8 @@ static Value *generateNewInstTree(ArrayRef<InstLane> Item, FixedVectorType *Ty,
 // do so.
 bool VectorCombine::foldShuffleToIdentity(Instruction &I) {
   auto *Ty = dyn_cast<FixedVectorType>(I.getType());
-  if (!Ty)
+  if (!Ty || !isa<Instruction>(I.getOperand(0)) ||
+      !isa<Instruction>(I.getOperand(1)))
     return false;
 
   SmallVector<InstLane> Start(Ty->getNumElements());

llvm/test/Transforms/VectorCombine/AArch64/shuffletoidentity.ll

@@ -15,7 +15,9 @@ define <8 x i8> @trivial(<8 x i8> %a) {
 
 define <4 x i32> @add_same_operands(<4 x i32> %x) {
 ; CHECK-LABEL: @add_same_operands(
-; CHECK-NEXT:    [[REVSHUF:%.*]] = add <4 x i32> [[X:%.*]], [[X]]
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <4 x i32> [[X:%.*]], <4 x i32> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
+; CHECK-NEXT:    [[ADD:%.*]] = add <4 x i32> [[SHUF]], [[SHUF]]
+; CHECK-NEXT:    [[REVSHUF:%.*]] = shufflevector <4 x i32> [[ADD]], <4 x i32> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
 ; CHECK-NEXT:    ret <4 x i32> [[REVSHUF]]
 ;
   %shuf = shufflevector <4 x i32> %x, <4 x i32> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
@@ -362,7 +364,8 @@ define <8 x i8> @inner_shuffle(<8 x i8> %a, <8 x i8> %b, <8 x i8> %c) {
 define <4 x i32> @extrause_add_same_operands(<4 x i32> %x) {
 ; CHECK-LABEL: @extrause_add_same_operands(
 ; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <4 x i32> [[X:%.*]], <4 x i32> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
-; CHECK-NEXT:    [[REVSHUF:%.*]] = add <4 x i32> [[X]], [[X]]
+; CHECK-NEXT:    [[ADD:%.*]] = add <4 x i32> [[SHUF]], [[SHUF]]
+; CHECK-NEXT:    [[REVSHUF:%.*]] = shufflevector <4 x i32> [[ADD]], <4 x i32> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
 ; CHECK-NEXT:    [[ADD2:%.*]] = add <4 x i32> [[SHUF]], [[REVSHUF]]
 ; CHECK-NEXT:    ret <4 x i32> [[ADD2]]
 ;
@@ -510,7 +513,9 @@ define <8 x half> @fma(<8 x half> %a, <8 x half> %b, <8 x half> %c) {
 
 define <4 x i64> @single_zext(<4 x i32> %x) {
 ; CHECK-LABEL: @single_zext(
-; CHECK-NEXT:    [[REVSHUF:%.*]] = zext <4 x i32> [[X:%.*]] to <4 x i64>
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <4 x i32> [[X:%.*]], <4 x i32> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
+; CHECK-NEXT:    [[ZEXT:%.*]] = zext <4 x i32> [[SHUF]] to <4 x i64>
+; CHECK-NEXT:    [[REVSHUF:%.*]] = shufflevector <4 x i64> [[ZEXT]], <4 x i64> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
 ; CHECK-NEXT:    ret <4 x i64> [[REVSHUF]]
 ;
   %shuf = shufflevector <4 x i32> %x, <4 x i32> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
@@ -690,8 +695,10 @@ define void @trunc(<8 x i64> %a, <8 x i64> %b, ptr %p) {
 
 define <4 x i64> @zext_chain(<4 x i16> %x) {
 ; CHECK-LABEL: @zext_chain(
-; CHECK-NEXT:    [[TMP1:%.*]] = zext <4 x i16> [[X:%.*]] to <4 x i32>
-; CHECK-NEXT:    [[REVSHUF:%.*]] = sext <4 x i32> [[TMP1]] to <4 x i64>
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <4 x i16> [[X:%.*]], <4 x i16> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
+; CHECK-NEXT:    [[ZEXT:%.*]] = zext <4 x i16> [[SHUF]] to <4 x i32>
+; CHECK-NEXT:    [[SEXT:%.*]] = sext <4 x i32> [[ZEXT]] to <4 x i64>
+; CHECK-NEXT:    [[REVSHUF:%.*]] = shufflevector <4 x i64> [[SEXT]], <4 x i64> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
 ; CHECK-NEXT:    ret <4 x i64> [[REVSHUF]]
 ;
   %shuf = shufflevector <4 x i16> %x, <4 x i16> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
@@ -892,11 +899,13 @@ entry:
 
 define <4 x i8> @singleop(<4 x i8> %a, <4 x i8> %b) {
 ; CHECK-LABEL: @singleop(
-; CHECK-NEXT:    [[TMP1:%.*]] = shufflevector <4 x i8> [[B:%.*]], <4 x i8> poison, <4 x i32> zeroinitializer
-; CHECK-NEXT:    [[TMP2:%.*]] = zext <4 x i8> [[A:%.*]] to <4 x i16>
-; CHECK-NEXT:    [[TMP3:%.*]] = zext <4 x i8> [[TMP1]] to <4 x i16>
-; CHECK-NEXT:    [[TMP4:%.*]] = add <4 x i16> [[TMP2]], [[TMP3]]
-; CHECK-NEXT:    [[R:%.*]] = trunc <4 x i16> [[TMP4]] to <4 x i8>
+; CHECK-NEXT:    [[A1:%.*]] = shufflevector <4 x i8> [[A:%.*]], <4 x i8> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
+; CHECK-NEXT:    [[B1:%.*]] = shufflevector <4 x i8> [[B:%.*]], <4 x i8> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[A2:%.*]] = zext <4 x i8> [[A1]] to <4 x i16>
+; CHECK-NEXT:    [[B2:%.*]] = zext <4 x i8> [[B1]] to <4 x i16>
+; CHECK-NEXT:    [[AB:%.*]] = add <4 x i16> [[A2]], [[B2]]
+; CHECK-NEXT:    [[T:%.*]] = trunc <4 x i16> [[AB]] to <4 x i8>
+; CHECK-NEXT:    [[R:%.*]] = shufflevector <4 x i8> [[T]], <4 x i8> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
 ; CHECK-NEXT:    ret <4 x i8> [[R]]
 ;
   %a1 = shufflevector <4 x i8> %a, <4 x i8> poison, <4 x i32> <i32 3, i32 2, i32 1, i32 0>