!fixup address comments, thanks

Author: fhahn

llvm/lib/Transforms/Vectorize/VectorCombine.cpp

@@ -2795,7 +2795,7 @@ bool VectorCombine::foldShuffleExtExtracts(Instruction &I) {
       !isa<LoadInst>(L))
     return false;
   auto *InnerExt = cast<Instruction>(I.getOperand(0));
-  auto *OuterExt = dyn_cast<Instruction>(*I.user_begin());
+  auto *OuterExt = cast<Instruction>(*I.user_begin());
   if (!isa<SExtInst, ZExtInst>(OuterExt))
     return false;
 
@@ -2819,8 +2819,8 @@ bool VectorCombine::foldShuffleExtExtracts(Instruction &I) {
   Builder.SetInsertPoint(*L->getInsertionPointAfterDef());
   auto *NewLoad = cast<LoadInst>(
       Builder.CreateLoad(SrcTy, L->getOperand(0), L->getName() + ".vec"));
-  auto *NewExt = isa<ZExtInst>(InnerExt) ? Builder.CreateZExt(NewLoad, DstTy)
-                                         : Builder.CreateSExt(NewLoad, DstTy);
+  auto *NewExt = isa<ZExtInst>(InnerExt) ? Builder.CreateZExt(NewLoad, DstTy, "vec.ext", InnerExt->hasNonNeg())
+                                         : Builder.CreateSExt(NewLoad, DstTy, "vec.ext");
   OuterExt->replaceAllUsesWith(NewExt);
   replaceValue(*OuterExt, *NewExt);
   Worklist.pushValue(NewLoad);

llvm/test/Transforms/VectorCombine/AArch64/combine-shuffle-ext.ll

@@ -30,7 +30,7 @@ define <4 x i32> @load_i32_zext_to_v4i32_both_nneg(ptr %di) {
 ; CHECK-SAME: ptr [[DI:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*:]]
 ; CHECK-NEXT:    [[L_VEC:%.*]] = load <4 x i8>, ptr [[DI]], align 4
-; CHECK-NEXT:    [[EXT_2:%.*]] = zext <4 x i8> [[L_VEC]] to <4 x i32>
+; CHECK-NEXT:    [[EXT_2:%.*]] = zext nneg <4 x i8> [[L_VEC]] to <4 x i32>
 ; CHECK-NEXT:    ret <4 x i32> [[EXT_2]]
 ;
 entry:
@@ -47,12 +47,8 @@ define <4 x i32> @load_i32_zext_to_v4i32_inner_nneg(ptr %di) {
 ; CHECK-LABEL: define <4 x i32> @load_i32_zext_to_v4i32_inner_nneg(
 ; CHECK-SAME: ptr [[DI:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*:]]
-; CHECK-NEXT:    [[L:%.*]] = load i32, ptr [[DI]], align 4
-; CHECK-NEXT:    [[VEC_INS:%.*]] = insertelement <2 x i32> <i32 poison, i32 0>, i32 [[L]], i64 0
-; CHECK-NEXT:    [[VEC_BC:%.*]] = bitcast <2 x i32> [[VEC_INS]] to <8 x i8>
-; CHECK-NEXT:    [[E_1:%.*]] = zext nneg <8 x i8> [[VEC_BC]] to <8 x i16>
-; CHECK-NEXT:    [[VEC_SHUFFLE:%.*]] = shufflevector <8 x i16> [[E_1]], <8 x i16> poison, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
-; CHECK-NEXT:    [[EXT_2:%.*]] = zext <4 x i16> [[VEC_SHUFFLE]] to <4 x i32>
+; CHECK-NEXT:    [[L_VEC:%.*]] = load <4 x i8>, ptr [[DI]], align 4
+; CHECK-NEXT:    [[EXT_2:%.*]] = zext nneg <4 x i8> [[L_VEC]] to <4 x i32>
 ; CHECK-NEXT:    ret <4 x i32> [[EXT_2]]
 ;
 entry:
@@ -69,12 +65,8 @@ define <4 x i32> @load_i32_zext_to_v4i32_outer_nneg(ptr %di) {
 ; CHECK-LABEL: define <4 x i32> @load_i32_zext_to_v4i32_outer_nneg(
 ; CHECK-SAME: ptr [[DI:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*:]]
-; CHECK-NEXT:    [[L:%.*]] = load i32, ptr [[DI]], align 4
-; CHECK-NEXT:    [[VEC_INS:%.*]] = insertelement <2 x i32> <i32 poison, i32 0>, i32 [[L]], i64 0
-; CHECK-NEXT:    [[VEC_BC:%.*]] = bitcast <2 x i32> [[VEC_INS]] to <8 x i8>
-; CHECK-NEXT:    [[E_1:%.*]] = zext <8 x i8> [[VEC_BC]] to <8 x i16>
-; CHECK-NEXT:    [[VEC_SHUFFLE:%.*]] = shufflevector <8 x i16> [[E_1]], <8 x i16> poison, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
-; CHECK-NEXT:    [[EXT_2:%.*]] = zext nneg <4 x i16> [[VEC_SHUFFLE]] to <4 x i32>
+; CHECK-NEXT:    [[L_VEC:%.*]] = load <4 x i8>, ptr [[DI]], align 4
+; CHECK-NEXT:    [[EXT_2:%.*]] = zext <4 x i8> [[L_VEC]] to <4 x i32>
 ; CHECK-NEXT:    ret <4 x i32> [[EXT_2]]
 ;
 entry:
@@ -91,12 +83,8 @@ define <4 x i32> @load_i32_zext_to_v4i32_inner_nneg_outer_sext(ptr %di) {
 ; CHECK-LABEL: define <4 x i32> @load_i32_zext_to_v4i32_inner_nneg_outer_sext(
 ; CHECK-SAME: ptr [[DI:%.*]]) {
 ; CHECK-NEXT:  [[ENTRY:.*:]]
-; CHECK-NEXT:    [[L:%.*]] = load i32, ptr [[DI]], align 4
-; CHECK-NEXT:    [[VEC_INS:%.*]] = insertelement <2 x i32> <i32 poison, i32 0>, i32 [[L]], i64 0
-; CHECK-NEXT:    [[VEC_BC:%.*]] = bitcast <2 x i32> [[VEC_INS]] to <8 x i8>
-; CHECK-NEXT:    [[E_1:%.*]] = zext nneg <8 x i8> [[VEC_BC]] to <8 x i16>
-; CHECK-NEXT:    [[VEC_SHUFFLE:%.*]] = shufflevector <8 x i16> [[E_1]], <8 x i16> poison, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
-; CHECK-NEXT:    [[EXT_2:%.*]] = sext <4 x i16> [[VEC_SHUFFLE]] to <4 x i32>
+; CHECK-NEXT:    [[L_VEC:%.*]] = load <4 x i8>, ptr [[DI]], align 4
+; CHECK-NEXT:    [[EXT_2:%.*]] = zext nneg <4 x i8> [[L_VEC]] to <4 x i32>
 ; CHECK-NEXT:    ret <4 x i32> [[EXT_2]]
 ;
 entry: