[llvm] [VPlan] Use pointer to member 0 as VPInterleaveRecipe's pointer arg. (PR #106431)

[via llvm-commits]

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@@ -1286,19 +1282,16 @@ define void @PR27626_4(ptr %a, i32 %x, i32 %y, i32 %z, i64 %n) {
 ; CHECK-NEXT:    [[TMP3:%.*]] = or disjoint i64 [[OFFSET_IDX]], 2
 ; CHECK-NEXT:    [[TMP4:%.*]] = or disjoint i64 [[OFFSET_IDX]], 4
 ; CHECK-NEXT:    [[TMP5:%.*]] = or disjoint i64 [[OFFSET_IDX]], 6
-; CHECK-NEXT:    [[TMP6:%.*]] = or disjoint i64 [[OFFSET_IDX]], 1
 ; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr inbounds i32, ptr [[A:%.*]], i64 [[OFFSET_IDX]]
 ; CHECK-NEXT:    [[TMP8:%.*]] = getelementptr inbounds i32, ptr [[A]], i64 [[TMP3]]
 ; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i32, ptr [[A]], i64 [[TMP4]]
 ; CHECK-NEXT:    [[TMP10:%.*]] = getelementptr inbounds i32, ptr [[A]], i64 [[TMP5]]
-; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i32, ptr [[A]], i64 [[TMP6]]
 ; CHECK-NEXT:    store i32 [[X:%.*]], ptr [[TMP7]], align 4
 ; CHECK-NEXT:    store i32 [[X]], ptr [[TMP8]], align 4
 ; CHECK-NEXT:    store i32 [[X]], ptr [[TMP9]], align 4
 ; CHECK-NEXT:    store i32 [[X]], ptr [[TMP10]], align 4
-; CHECK-NEXT:    [[TMP12:%.*]] = getelementptr inbounds i8, ptr [[TMP11]], i64 -4
 ; CHECK-NEXT:    [[INTERLEAVED_VEC:%.*]] = shufflevector <4 x i32> [[BROADCAST_SPLAT]], <4 x i32> [[BROADCAST_SPLAT2]], <8 x i32> <i32 0, i32 4, i32 1, i32 5, i32 2, i32 6, i32 3, i32 7>
-; CHECK-NEXT:    store <8 x i32> [[INTERLEAVED_VEC]], ptr [[TMP12]], align 4
+; CHECK-NEXT:    store <8 x i32> [[INTERLEAVED_VEC]], ptr [[TMP7]], align 4
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ayalz wrote:

Note: this stores INTERLEAVED_VEC at A[OFFSET_IDX], rather than to A[OFFSET_IDX+(1*4)-4]
Stores of X should be dce'd.

https://github.com/llvm/llvm-project/pull/106431