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| author | Nikita Popov <npopov@redhat.com> | 2022-01-04 16:04:25 +0100 |
|---|---|---|
| committer | Nikita Popov <npopov@redhat.com> | 2022-01-04 16:08:09 +0100 |
| commit | 6c031780aa2c08996d1351de5e7541c75d6645c5 (patch) | |
| tree | 57a0984598752431626a473b5870cc015c6f3e05 | |
| parent | 25448826dd4c1965be08fa38cc02de9551084262 (diff) | |
| download | llvm-6c031780aa2c08996d1351de5e7541c75d6645c5.tar.gz | |
[ConstantFold] Remove another incorrect icmp of gep fold
This folded (null + X) == g to false, but of course this is
incorrect if X == g.
Possibly this got confused with the null == g case, which is
already handled elsewhere.
| -rw-r--r-- | llvm/lib/IR/ConstantFold.cpp | 7 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstSimplify/ConstProp/icmp-global.ll | 4 |
2 files changed, 3 insertions, 8 deletions
diff --git a/llvm/lib/IR/ConstantFold.cpp b/llvm/lib/IR/ConstantFold.cpp index 66e3a75833e2..0d76dd732d61 100644 --- a/llvm/lib/IR/ConstantFold.cpp +++ b/llvm/lib/IR/ConstantFold.cpp @@ -1541,12 +1541,7 @@ static ICmpInst::Predicate evaluateICmpRelation(Constant *V1, Constant *V2, return ICmpInst::ICMP_UGT; } } else if (const GlobalValue *GV2 = dyn_cast<GlobalValue>(V2)) { - if (isa<ConstantPointerNull>(CE1Op0)) { - // If its not weak linkage, the GVal must have a non-zero address - // so the result is less-than - if (!GV2->hasExternalWeakLinkage()) - return ICmpInst::ICMP_ULT; - } else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CE1Op0)) { + if (const GlobalValue *GV = dyn_cast<GlobalValue>(CE1Op0)) { if (GV != GV2) { if (CE1GEP->hasAllZeroIndices()) return areGlobalsPotentiallyEqual(GV, GV2); diff --git a/llvm/test/Transforms/InstSimplify/ConstProp/icmp-global.ll b/llvm/test/Transforms/InstSimplify/ConstProp/icmp-global.ll index cdf6be0e5243..aeb6ab4e504f 100644 --- a/llvm/test/Transforms/InstSimplify/ConstProp/icmp-global.ll +++ b/llvm/test/Transforms/InstSimplify/ConstProp/icmp-global.ll @@ -168,7 +168,7 @@ define i1 @null_gep_ugt_null_constant_int() { define i1 @null_gep_ne_global() { ; CHECK-LABEL: @null_gep_ne_global( -; CHECK-NEXT: ret i1 true +; CHECK-NEXT: ret i1 icmp ne (i8* getelementptr (i8, i8* null, i64 ptrtoint (i8* @g3 to i64)), i8* @g3) ; %gep = getelementptr i8, i8* null, i64 ptrtoint (i8* @g3 to i64) %cmp = icmp ne i8* %gep, @g3 @@ -177,7 +177,7 @@ define i1 @null_gep_ne_global() { define i1 @null_gep_ult_global() { ; CHECK-LABEL: @null_gep_ult_global( -; CHECK-NEXT: ret i1 true +; CHECK-NEXT: ret i1 icmp ult (i8* getelementptr (i8, i8* null, i64 ptrtoint (i8* @g3 to i64)), i8* @g3) ; %gep = getelementptr i8, i8* null, i64 ptrtoint (i8* @g3 to i64) %cmp = icmp ult i8* %gep, @g3 |