http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46647
Summary: Can't inline memset with -1
Product: gcc
Version: 4.6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: hjl.to...@gmail.com
CC: ubiz...@gmail.com
[...@gnu-16 gcc]$ cat /tmp/x.i
char a[4];
int
func1 (void)
{
__builtin_memset (a,-1,sizeof (a));
return 0;
}
int
func2 (void)
{
__builtin_memset (a,123,sizeof (a));
return 0;
}
[...@gnu-16 gcc]$ ./xgcc -B./ -S /tmp/x.i -O2 -m32
[...@gnu-16 gcc]$ cat x.s
.file "x.i"
.text
.p2align 4,,15
.globl func1
.type func1, @function
func1:
.LFB0:
.cfi_startproc
subl $28, %esp
.cfi_def_cfa_offset 32
movl $4, 8(%esp)
movl $-1, 4(%esp)
movl $a, (%esp)
call memset
xorl %eax, %eax
addl $28, %esp
.cfi_def_cfa_offset 4
ret
.cfi_endproc
.LFE0:
.size func1, .-func1
.p2align 4,,15
.globl func2
.type func2, @function
func2:
.LFB1:
.cfi_startproc
movl $2071690107, a
xorl %eax, %eax
ret
.cfi_endproc
.LFE1:
.size func2, .-func2
.comm a,4,1
.ident "GCC: (GNU) 4.6.0 20101124 (experimental) [trunk revision
167121]"
.section .note.GNU-stack,"",@progbits
[...@gnu-16 gcc]$
Why can't we inline __builtin_memset (a,123,sizeof (a))?
