[clang] [InstCombine] Canonicalize constant GEPs to i8 source element type (PR #68882)

[Nikita Popov via cfe-commits]

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@@ -3,8 +3,9 @@
 
 define ptr @f1(ptr %arg, i64 %arg1) {
 ; CHECK-LABEL: @f1(
-; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr [6 x i32], ptr [[ARG:%.*]], i64 3, i64 [[ARG1:%.*]]
-; CHECK-NEXT:    ret ptr [[TMP1]]
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i8, ptr [[ARG:%.*]], i64 72
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr [6 x i32], ptr [[TMP1]], i64 0, i64 [[ARG1:%.*]]
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nikic wrote:

Possible regression. We kind of want to move in his direction, though it happens by accident here.

https://github.com/llvm/llvm-project/pull/68882