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

[Nikita Popov via cfe-commits]

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@@ -637,9 +637,8 @@ define ptr @select_of_gep(i1 %c, ptr %p) {
 
 define ptr @select_of_gep_different_type(i1 %c, ptr %p) {
 ; CHECK-LABEL: @select_of_gep_different_type(
-; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i32, ptr [[P:%.*]], i64 1
-; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr i64, ptr [[P]], i64 2
-; CHECK-NEXT:    [[S:%.*]] = select i1 [[C:%.*]], ptr [[GEP1]], ptr [[GEP2]]
+; CHECK-NEXT:    [[S_V:%.*]] = select i1 [[C:%.*]], i64 4, i64 16
+; CHECK-NEXT:    [[S:%.*]] = getelementptr i8, ptr [[P:%.*]], i64 [[S_V]]
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nikic wrote:

Improvement.

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