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Re: PATCH: PR target/47715: [x32] Use SImode for thread pointer
On Fri, Jul 29, 2011 at 12:28 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
>>>>>>>>> TP is 32bit in x32 ?For load_tp_x32, we load SImode value and
>>>>>>>>> zero-extend to DImode. For add_tp_x32, we are adding SImode
>>>>>>>>> value. ?We can't pretend TP is 64bit. ?load_tp_x32 and add_tp_x32
>>>>>>>>> must take SImode TP.
>>
>>> Here is the revised patch. ?The difference is I changed *add_tp_x32 to SImode.
>>> For
>>>
>>> ---
>>> extern __thread int __libc_errno __attribute__ ((tls_model ("initial-exec")));
>>>
>>> int *
>>> __errno_location (void)
>>> {
>>> ?return &__libc_errno;
>>> }
>>> ---
>>>
>>> compiled with -mx32 -O2 -fPIC ?DImode *add_tp_x32 generates:
>>>
>>> ? ? ? ?movq ? ?__libc_errno@gottpoff(%rip), %rax
>>> ? ? ? ?addl ? ?%fs:0, %eax
>>> ? ? ? ?mov ? ? %eax, %eax
>>> ? ? ? ?ret
>>>
>>> SImode *add_tp_x32 generates:
>>>
>>> ? ? ? ?movl ? ?%fs:0, %eax
>>> ? ? ? ?addl ? ?__libc_errno@gottpoff(%rip), %eax
>>> ? ? ? ?ret
>>
>> This happens because combine can't combine DImode load and SImode plus
>> RTXes. These RTXes have to be in Pmode, see the intention in
>> legitimize_tls_address, also for TARGET_GNU2_TLS.
>>
>> Can you please debug what goes wrong with tp_add_x32 in DImode?
>>
>
> We start with
Uh, we didn't understand each other... can you please debug what goes
wrong with glibc runtime test?
Thanks,
Uros.