[llvm] [InstCombine] Don't require GEP in indexed compare fold (PR #81614)

[Nikita Popov via llvm-commits]

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@@ -36,10 +36,12 @@ define void @test_fill_with_foreach([2 x i64] %elems.coerce) {
 ; CHECK-NEXT:    tail call void @error()
 ; CHECK-NEXT:    br label [[COMMON_RET]]
 ; CHECK:       for.body:
-; CHECK-NEXT:    [[__BEGIN1_SROA_0_03:%.*]] = phi ptr [ [[INCDEC_PTR_I:%.*]], [[FOR_BODY]] ], [ [[TMP0]], [[FOR_COND_PREHEADER_SPLIT]] ]
-; CHECK-NEXT:    tail call void @use(ptr noundef nonnull align 4 dereferenceable(4) [[__BEGIN1_SROA_0_03]])
-; CHECK-NEXT:    [[INCDEC_PTR_I]] = getelementptr inbounds i8, ptr [[__BEGIN1_SROA_0_03]], i64 4
-; CHECK-NEXT:    [[CMP_I_NOT:%.*]] = icmp eq ptr [[INCDEC_PTR_I]], [[ADD_PTR_I]]
+; CHECK-NEXT:    [[__BEGIN1_SROA_0_0_PTR4:%.*]] = phi ptr [ [[__BEGIN1_SROA_0_0_PTR:%.*]], [[FOR_BODY]] ], [ [[TMP0]], [[FOR_COND_PREHEADER_SPLIT]] ]
+; CHECK-NEXT:    [[__BEGIN1_SROA_0_0_IDX3:%.*]] = phi i64 [ [[__BEGIN1_SROA_0_0_ADD:%.*]], [[FOR_BODY]] ], [ 0, [[FOR_COND_PREHEADER_SPLIT]] ]
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nikic wrote:

I submitted https://github.com/llvm/llvm-project/pull/81151 for this regression.

https://github.com/llvm/llvm-project/pull/81614