diff --git a/llvm/test/Analysis/BasicAA/gep-modulo.ll b/llvm/test/Analysis/BasicAA/gep-modulo.ll index acdbaefefd71c..79782fad44872 100644 --- a/llvm/test/Analysis/BasicAA/gep-modulo.ll +++ b/llvm/test/Analysis/BasicAA/gep-modulo.ll @@ -192,7 +192,7 @@ define void @may_overflow_i32_sext([16 x i8]* %ptr, i32 %idx) { ; CHECK-LABEL: Function: may_overflow_i32_sext: 3 pointers, 0 call sites ; CHECK-NEXT: MayAlias: [16 x i8]* %ptr, i8* %gep.idx ; CHECK-NEXT: PartialAlias (off 3): [16 x i8]* %ptr, i8* %gep.3 -; CHECK-NEXT: MayAlias: i8* %gep.3, i8* %gep.idx +; CHECK-NEXT: MayAlias: i8* %gep.3, i8* %gep.idx ; %mul = mul i32 %idx, 678152731 %sub = sub i32 %mul, 1582356375 @@ -208,7 +208,7 @@ define void @nuw_nsw_i32_sext([16 x i8]* %ptr, i32 %idx) { ; CHECK-LABEL: Function: nuw_nsw_i32_sext: 3 pointers, 0 call sites ; CHECK-NEXT: NoAlias: [16 x i8]* %ptr, i8* %gep.idx ; CHECK-NEXT: PartialAlias (off 3): [16 x i8]* %ptr, i8* %gep.3 -; CHECK-NEXT: NoAlias: i8* %gep.3, i8* %gep.idx +; CHECK-NEXT: NoAlias: i8* %gep.3, i8* %gep.idx ; %mul = mul nuw nsw i32 %idx, 678152731 %sub = sub nuw nsw i32 %mul, 1582356375 @@ -225,7 +225,7 @@ define void @may_overflow_i32_zext([16 x i8]* %ptr, i32 %idx) { ; CHECK-LABEL: Function: may_overflow_i32_zext: 3 pointers, 0 call sites ; CHECK-NEXT: MayAlias: [16 x i8]* %ptr, i8* %gep.idx ; CHECK-NEXT: PartialAlias (off 3): [16 x i8]* %ptr, i8* %gep.3 -; CHECK-NEXT: MayAlias: i8* %gep.3, i8* %gep.idx +; CHECK-NEXT: MayAlias: i8* %gep.3, i8* %gep.idx ; %mul = mul i32 %idx, 678152731 %sub = sub i32 %mul, 1582356375 @@ -241,7 +241,7 @@ define void @nuw_nsw_i32_zext([16 x i8]* %ptr, i32 %idx) { ; CHECK-LABEL: Function: nuw_nsw_i32_zext: 3 pointers, 0 call sites ; CHECK-NEXT: NoAlias: [16 x i8]* %ptr, i8* %gep.idx ; CHECK-NEXT: PartialAlias (off 3): [16 x i8]* %ptr, i8* %gep.3 -; CHECK-NEXT: NoAlias: i8* %gep.3, i8* %gep.idx +; CHECK-NEXT: NoAlias: i8* %gep.3, i8* %gep.idx ; %mul = mul nuw nsw i32 %idx, 678152731 %sub = sub nuw nsw i32 %mul, 1582356375 @@ -252,3 +252,22 @@ define void @nuw_nsw_i32_zext([16 x i8]* %ptr, i32 %idx) { store i8 1, i8* %gep.3, align 1 ret void } + +; %mul.1 and %sub.2 are equal, if %idx = 9, because %mul.1 overflows. Hence +; %gep.mul.1 and %gep.sub.2 may alias. +define void @may_overflow_pointer_diff([16 x i8]* %ptr, i64 %idx) { +; CHECK-LABEL: Function: may_overflow_pointer_diff: 3 pointers, 0 call sites +; CHECK-NEXT: MayAlias: [16 x i8]* %ptr, i8* %gep.mul.1 +; CHECK-NEXT: MayAlias: [16 x i8]* %ptr, i8* %gep.sub.2 +; CHECK-NEXT: NoAlias: i8* %gep.mul.1, i8* %gep.sub.2 +; + %mul.1 = mul i64 %idx, 6148914691236517207 + %gep.mul.1 = getelementptr [16 x i8], [16 x i8]* %ptr, i32 0, i64 %mul.1 + store i8 1, i8* %gep.mul.1, align 1 + %mul.2 = mul nsw i64 %idx, 3 + %sub.2 = sub nsw i64 %mul.2, 12 + %gep.sub.2= getelementptr [16 x i8], [16 x i8]* %ptr, i32 0, i64 %sub.2 + store i8 0, i8* %gep.sub.2, align 1 + + ret void +}