753c51bf88
AST checks aliasing with MustAlias sets by only checking the representative pointer (getSomePointer). This is only correct if the Size and AATags information of that pointer also includes the Size/AATags of all other pointers in the set. When we add a new pointer to the AliasSet, we do perform this update (see the code in AliasSet::addPointer). However, if a pointer already in the MustAlias set is used with a new size, we currently do not update the representative pointer, resulting in miscompilations. Fix this by adding the missing update. This is a targeted fix using the current representation. There are a couple of alternatives: * For MustAlias sets, don't store per-pointer Size/AATags at all. This would make it clear that there is only one set of common Size/AATags for all pointers. * Check against all pointers in the set even for MustAlias. This is what https://github.com/llvm/llvm-project/pull/65731 proposes to do as part of a larger change to AST representation. Fixes https://github.com/llvm/llvm-project/issues/64897.
45 lines
1.5 KiB
LLVM
45 lines
1.5 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
|
|
; RUN: opt -S -passes=licm < %s | FileCheck %s
|
|
|
|
define void @test(i1 %c, i8 %x) {
|
|
; CHECK-LABEL: define void @test(
|
|
; CHECK-SAME: i1 [[C:%.*]], i8 [[X:%.*]]) {
|
|
; CHECK-NEXT: start:
|
|
; CHECK-NEXT: [[A:%.*]] = alloca [16 x i8], align 8
|
|
; CHECK-NEXT: [[P:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 8
|
|
; CHECK-NEXT: [[P_COPY:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 8
|
|
; CHECK-NEXT: [[P2:%.*]] = getelementptr inbounds i8, ptr [[A]], i64 12
|
|
; CHECK-NEXT: br label [[LOOP:%.*]]
|
|
; CHECK: loop:
|
|
; CHECK-NEXT: store i32 286331153, ptr [[P]], align 4
|
|
; CHECK-NEXT: store i32 34, ptr [[P_COPY]], align 4
|
|
; CHECK-NEXT: store i64 3689348814741910323, ptr [[P_COPY]], align 4
|
|
; CHECK-NEXT: [[VAL:%.*]] = load i8, ptr [[P2]], align 1
|
|
; CHECK-NEXT: call void @use(i8 [[VAL]])
|
|
; CHECK-NEXT: store i8 0, ptr [[P2]], align 1
|
|
; CHECK-NEXT: br i1 [[C]], label [[LOOP]], label [[EXIT:%.*]]
|
|
; CHECK: exit:
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
start:
|
|
%a = alloca [16 x i8], align 8
|
|
%p = getelementptr inbounds i8, ptr %a, i64 8
|
|
%p.copy = getelementptr inbounds i8, ptr %a, i64 8
|
|
%p2 = getelementptr inbounds i8, ptr %a, i64 12
|
|
br label %loop
|
|
|
|
loop:
|
|
store i32 u0x11111111, ptr %p
|
|
store i32 u0x22, ptr %p.copy
|
|
store i64 u0x3333333333333333, ptr %p.copy
|
|
%val = load i8, ptr %p2
|
|
call void @use(i8 %val)
|
|
store i8 0, ptr %p2
|
|
br i1 %c, label %loop, label %exit
|
|
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
declare void @use(i8)
|