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| author | Nikita Popov <npopov@redhat.com> | 2023-05-31 14:53:44 +0200 |
|---|---|---|
| committer | Tom Stellard <tstellar@redhat.com> | 2023-06-01 09:44:36 -0700 |
| commit | 42f2e6efd84464e2d02f2524b7feecb00efd6ab7 (patch) | |
| tree | 9842b4352e087a1a966051b899e463c08b5e08af | |
| parent | 57c54b25929c138b6e933a56a8549a8d59913e75 (diff) | |
| download | llvm-42f2e6efd84464e2d02f2524b7feecb00efd6ab7.zip llvm-42f2e6efd84464e2d02f2524b7feecb00efd6ab7.tar.gz llvm-42f2e6efd84464e2d02f2524b7feecb00efd6ab7.tar.bz2 | |
[AA] Fix comparison of AliasResults (PR63019)
Comparison between two AliasResults implicitly decayed to comparison
of AliasResult::Kind. As a result, MergeAliasResults() ended up
considering two PartialAlias results with different offsets as
equivalent.
Fix this by adding an operator== implementation. To stay
compatible with extensive use of comparisons between AliasResult
and AliasResult::Kind, add an overload for that as well, which
will ignore the offset. In the future, it would probably be a
good idea to remove these implicit decays to AliasResult::Kind
and add dedicated methods to check for specific AliasResult kinds.
Fixes https://github.com/llvm/llvm-project/issues/63019.
(cherry picked from commit 97f0e7b06e6b76fd85fb81b8c12eba2255ff1742)
| -rw-r--r-- | llvm/include/llvm/Analysis/AliasAnalysis.h | 9 | ||||
| -rw-r--r-- | llvm/test/Transforms/GVN/pr63019.ll | 7 |
2 files changed, 12 insertions, 4 deletions
diff --git a/llvm/include/llvm/Analysis/AliasAnalysis.h b/llvm/include/llvm/Analysis/AliasAnalysis.h index 953e15e..8ac6e7d 100644 --- a/llvm/include/llvm/Analysis/AliasAnalysis.h +++ b/llvm/include/llvm/Analysis/AliasAnalysis.h @@ -116,6 +116,15 @@ public: operator Kind() const { return static_cast<Kind>(Alias); } + bool operator==(const AliasResult &Other) const { + return Alias == Other.Alias && HasOffset == Other.HasOffset && + Offset == Other.Offset; + } + bool operator!=(const AliasResult &Other) const { return !(*this == Other); } + + bool operator==(Kind K) const { return Alias == K; } + bool operator!=(Kind K) const { return !(*this == K); } + constexpr bool hasOffset() const { return HasOffset; } constexpr int32_t getOffset() const { assert(HasOffset && "No offset!"); diff --git a/llvm/test/Transforms/GVN/pr63019.ll b/llvm/test/Transforms/GVN/pr63019.ll index cf3a466..f2628a3 100644 --- a/llvm/test/Transforms/GVN/pr63019.ll +++ b/llvm/test/Transforms/GVN/pr63019.ll @@ -1,7 +1,7 @@ ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2 ; RUN: opt -S -passes=gvn < %s | FileCheck %s -; FIXME: This is a miscompile. +; Make sure the two offsets from the phi don't get merged incorrectly. define i8 @test(i1 %c, i64 %offset, ptr %ptr) { ; CHECK-LABEL: define i8 @test ; CHECK-SAME: (i1 [[C:%.*]], i64 [[OFFSET:%.*]], ptr [[PTR:%.*]]) { @@ -18,9 +18,8 @@ define i8 @test(i1 %c, i64 %offset, ptr %ptr) { ; CHECK-NEXT: store i8 0, ptr [[ALLOCA]], align 8 ; CHECK-NEXT: [[LOAD1:%.*]] = load i64, ptr [[ALLOCA]], align 8 ; CHECK-NEXT: store i64 [[LOAD1]], ptr [[PTR]], align 8 -; CHECK-NEXT: [[TMP0:%.*]] = lshr i64 [[LOAD1]], 16 -; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[TMP0]] to i8 -; CHECK-NEXT: ret i8 [[TMP1]] +; CHECK-NEXT: [[LOAD2:%.*]] = load i8, ptr [[PHI]], align 1 +; CHECK-NEXT: ret i8 [[LOAD2]] ; start: %alloca = alloca [8 x i8], align 8 |