noalias-byval.ll
1.48 KB
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; RUN: opt < %s -lint -disable-output 2>&1 | FileCheck %s
%s = type { i8 }
; Function Attrs: argmemonly nounwind
declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture writeonly, i8* nocapture readonly, i32, i1) #0
; Function Attrs: argmemonly nounwind
declare void @llvm.memset.p0i8.i32(i8* nocapture writeonly, i8, i32, i1) #0
declare void @f1(%s* noalias nocapture sret, %s* nocapture readnone)
define void @f2() {
entry:
%c = alloca %s
%tmp = alloca %s
%0 = bitcast %s* %c to i8*
%1 = bitcast %s* %tmp to i8*
call void @llvm.memset.p0i8.i32(i8* %0, i8 0, i32 1, i1 false)
call void @f1(%s* sret %c, %s* %c)
ret void
}
; Lint should complain about us passing %c to both arguments since one of them
; is noalias.
; CHECK: Unusual: noalias argument aliases another argument
; CHECK-NEXT: call void @f1(%s* sret %c, %s* %c)
declare void @f3(%s* noalias nocapture sret, %s* byval nocapture readnone)
define void @f4() {
entry:
%c = alloca %s
%tmp = alloca %s
%0 = bitcast %s* %c to i8*
%1 = bitcast %s* %tmp to i8*
call void @llvm.memset.p0i8.i32(i8* %0, i8 0, i32 1, i1 false)
call void @f3(%s* sret %c, %s* byval %c)
ret void
}
; Lint should not complain about passing %c to both arguments even if one is
; noalias, since the other one is byval, effectively copying the data to the
; stack instead of passing the pointer itself.
; CHECK-NOT: Unusual: noalias argument aliases another argument
; CHECK-NOT: call void @f3(%s* sret %c, %s* %c)
attributes #0 = { argmemonly nounwind }