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

[via llvm-commits]

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@@ -92,8 +93,9 @@ define void @test_ig_insert_pos_at_end_of_vpbb(ptr noalias %dst, ptr noalias %sr
 ; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
 ; CHECK-NEXT:    [[TMP3:%.*]] = add i64 [[INDEX]], 0
 ; CHECK-NEXT:    [[TMP4:%.*]] = getelementptr { i16, i16, i16, i16 }, ptr [[SRC]], i64 [[TMP3]], i32 2
-; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr i16, ptr [[TMP4]], i32 -2
-; CHECK-NEXT:    [[WIDE_VEC:%.*]] = load <16 x i16>, ptr [[TMP5]], align 2
+; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr i8, ptr [[TMP4]], i32 -4
+; CHECK-NEXT:    [[TMP51:%.*]] = getelementptr i16, ptr [[TMP5]], i32 0
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ayalz wrote:

Note: here a redundant gep with zero is added, replacing TMP4[-2:i16] with TMP4[-4:i8 + 0]

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