[Scalarizer] Use correct key for ExtractValueInst gather (llvm#149855)

Fixes llvm#149345

Effectively no-op pairs of insertelement-extractelement instructions
were being created due to the ExtractValueInst visitor in the Scalarizer
storing its scalarized result into the Scattered map using an incorrect
key (specifically the type used in the key).
This PR fixes this issue.

Author: Icohedron

llvm/lib/Transforms/Scalar/Scalarizer.cpp

@@ -1105,7 +1105,9 @@ bool ScalarizerVisitor::visitExtractValueInst(ExtractValueInst &EVI) {
     Res.push_back(ResElem);
   }
 
-  gather(&EVI, Res, *VS);
+  Type *ActualVecType = cast<FixedVectorType>(OpTy->getContainedType(Index));
+  std::optional<VectorSplit> AVS = getVectorSplit(ActualVecType);
+  gather(&EVI, Res, *AVS);
   return true;
 }
 

llvm/test/CodeGen/DirectX/UAddc.ll

@@ -35,14 +35,10 @@ define noundef <2 x i32> @test_UAddc_vec2(<2 x i32> noundef %a, <2 x i32> nounde
 ; CHECK-NEXT:    [[UADDC_I1:%.*]] = call [[DX_TYPES_I32C]] @dx.op.binaryWithCarryOrBorrow.i32(i32 44, i32 [[A_I1]], i32 [[B_I1]]) #[[ATTR0]]
 ; CHECK-NEXT:    [[CARRY_ELEM0:%.*]] = extractvalue [[DX_TYPES_I32C]] [[UADDC_I0]], 1
 ; CHECK-NEXT:    [[CARRY_ELEM1:%.*]] = extractvalue [[DX_TYPES_I32C]] [[UADDC_I1]], 1
-; CHECK-NEXT:    [[CARRY_UPTO0:%.*]] = insertelement <2 x i1> poison, i1 [[CARRY_ELEM0]], i64 0
-; CHECK-NEXT:    [[CARRY:%.*]] = insertelement <2 x i1> [[CARRY_UPTO0]], i1 [[CARRY_ELEM1]], i64 1
-; CHECK-NEXT:    [[CARRY_I0:%.*]] = extractelement <2 x i1> [[CARRY]], i64 0
-; CHECK-NEXT:    [[CARRY_I1:%.*]] = extractelement <2 x i1> [[CARRY]], i64 1
 ; CHECK-NEXT:    [[SUM_ELEM0:%.*]] = extractvalue [[DX_TYPES_I32C]] [[UADDC_I0]], 0
 ; CHECK-NEXT:    [[SUM_ELEM1:%.*]] = extractvalue [[DX_TYPES_I32C]] [[UADDC_I1]], 0
-; CHECK-NEXT:    [[CARRY_ZEXT_I0:%.*]] = zext i1 [[CARRY_I0]] to i32
-; CHECK-NEXT:    [[CARRY_ZEXT_I1:%.*]] = zext i1 [[CARRY_I1]] to i32
+; CHECK-NEXT:    [[CARRY_ZEXT_I0:%.*]] = zext i1 [[CARRY_ELEM0]] to i32
+; CHECK-NEXT:    [[CARRY_ZEXT_I1:%.*]] = zext i1 [[CARRY_ELEM1]] to i32
 ; CHECK-NEXT:    [[RESULT_I0:%.*]] = add i32 [[SUM_ELEM0]], [[CARRY_ZEXT_I0]]
 ; CHECK-NEXT:    [[RESULT_I1:%.*]] = add i32 [[SUM_ELEM1]], [[CARRY_ZEXT_I1]]
 ; CHECK-NEXT:    [[RESULT_UPTO0:%.*]] = insertelement <2 x i32> poison, i32 [[RESULT_I0]], i64 0

llvm/test/Transforms/Scalarizer/extractvalue-struct-of-vectors.ll

@@ -0,0 +1,23 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -passes='function(scalarizer)' -S < %s | FileCheck %s
+
+define void @func(<2 x i32> noundef %a, <2 x i32> noundef %b) {
+; CHECK-LABEL: define void @func(
+; CHECK-SAME: <2 x i32> noundef [[A:%.*]], <2 x i32> noundef [[B:%.*]]) {
+; CHECK-NEXT:    [[A_I0:%.*]] = extractelement <2 x i32> [[A]], i64 0
+; CHECK-NEXT:    [[B_I0:%.*]] = extractelement <2 x i32> [[B]], i64 0
+; CHECK-NEXT:    [[UADDC_I0:%.*]] = call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 [[A_I0]], i32 [[B_I0]])
+; CHECK-NEXT:    [[A_I1:%.*]] = extractelement <2 x i32> [[A]], i64 1
+; CHECK-NEXT:    [[B_I1:%.*]] = extractelement <2 x i32> [[B]], i64 1
+; CHECK-NEXT:    [[UADDC_I1:%.*]] = call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 [[A_I1]], i32 [[B_I1]])
+; CHECK-NEXT:    [[CARRY_ELEM1:%.*]] = extractvalue { i32, i1 } [[UADDC_I0]], 1
+; CHECK-NEXT:    [[CARRY_ELEM11:%.*]] = extractvalue { i32, i1 } [[UADDC_I1]], 1
+; CHECK-NEXT:    [[CARRY_ZEXT_I0:%.*]] = zext i1 [[CARRY_ELEM1]] to i32
+; CHECK-NEXT:    [[CARRY_ZEXT_I1:%.*]] = zext i1 [[CARRY_ELEM11]] to i32
+; CHECK-NEXT:    ret void
+;
+  %uaddc = call { <2 x i32>, <2 x i1> } @llvm.uadd.with.overflow.v2i32(<2 x i32> %a, <2 x i32> %b)
+  %carry = extractvalue { <2 x i32>, <2 x i1> } %uaddc, 1
+  %carry_zext = zext <2 x i1> %carry to <2 x i32>
+  ret void
+}