------- Comment #7 from hubicka at gcc dot gnu dot org 2008-09-26 22:56 -------
Hi,
so to be sure I didn't mess up anything. The following is testcase I use:
typedef struct shared_ptr_struct
{
unsigned long phase:48;
unsigned int thread:16;
void *addr;
} shared_ptr_t;
int y;
shared_ptr_t sp = { 1, 2, &y };
int
get_thread (shared_ptr_t p)
{
return p.thread;
}
int
main ()
{
int t = get_thread (sp);
return t;
}
The following is assembly I get:
get_thread:
.LFB0:
.cfi_startproc
movq %rdi, %rax
shrq $48, %rax
ret
.cfi_endproc
.LFE0:
.size get_thread, .-get_thread
.p2align 4,,15
.globl main
.type main, @function
main:
.LFB1:
.cfi_startproc
movq sp(%rip), %rdi
movq sp+8(%rip), %rsi
jmp get_thread
.cfi_endproc
.LFE1:
i.e. everything is passed in registers. I get same code from GCC-4.1
get_thread:
.LFB2:
movq %rdi, -16(%rsp)
movzwl -10(%rsp), %eax
ret
.LFE2:
.size get_thread, .-get_thread
.p2align 4,,15
.globl main
.type main, @function
main:
.LFB3:
movq sp(%rip), %rdi
movq sp+8(%rip), %rsi
jmp get_thread
.LFE3:
THis is oldest GCC I have around. I remember debugging this problem once
before, probably in different duplicate of this PR so I hope it is long fixed.
--
hubicka at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |WAITING
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19566
