3fedaf2a52
When materializing an available load value, do not explicitly materialize the undef values from dead blocks. Doing so will will force creation of a phi with an undef operand, even if there is a dominating definition. The phi will be folded away on subsequent GVN iterations, but by then we may have already poisoned MDA cache slots. Simply don't register these values in the first place, and let SSAUpdater do its thing.
37 lines
1020 B
LLVM
37 lines
1020 B
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
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; RUN: opt -S -gvn < %s | FileCheck %s
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define i64 @test(i64** noalias %p, i64* noalias %q) {
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; CHECK-LABEL: @test(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: store i64* [[Q:%.*]], i64** [[P:%.*]], align 8
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; CHECK-NEXT: br i1 false, label [[IF:%.*]], label [[MERGE:%.*]]
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; CHECK: if:
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; CHECK-NEXT: call void @clobber(i64** [[P]])
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; CHECK-NEXT: br label [[MERGE]]
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; CHECK: merge:
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; CHECK-NEXT: store i64 1, i64* [[Q]], align 4
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; CHECK-NEXT: [[Q3:%.*]] = getelementptr i64, i64* [[Q]], i64 1
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; CHECK-NEXT: store i64 2, i64* [[Q3]], align 4
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; CHECK-NEXT: ret i64 1
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;
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entry:
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store i64* %q, i64** %p
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br i1 false, label %if, label %merge
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if:
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call void @clobber(i64** %p)
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br label %merge
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merge:
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%q2 = load i64*, i64** %p
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store i64 1, i64* %q2
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%v = load i64, i64* %q
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%q3 = getelementptr i64, i64* %q, i64 %v
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store i64 2, i64* %q3
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%v2 = load i64, i64* %q
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ret i64 %v2
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}
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declare void @clobber(i64** %p)
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