On Tue, Mar 13, 2012 at 3:37 AM, Uros Bizjak <ubiz...@gmail.com> wrote:
> On Tue, Mar 13, 2012 at 8:11 AM, Uros Bizjak <ubiz...@gmail.com> wrote:
>
>>>>> Please try attached patch. It introduces TARGET_TLS_INDIRECT_SEG_REFS
>>>>> to block only indirect seg references.
>>>
>>> There is no regression.
>>
>> Thanks, committed to mainline SVN with following ChangeLog:
>>
>> 2012-03-13 Uros Bizjak <ubiz...@gmail.com>
>>
>> * config/i386/i386.h (TARGET_TLS_INDIRECT_SEG_REFS): New.
>> * config/i386/i386.c (ix86_decompose_address): Use
>> TARGET_TLS_INDIRECT_SEG_REFS to prevent %fs:(%reg) addresses.
>> (legitimize_tls_address): Use TARGET_TLS_INDIRECT_SEG_REFS to load
>> thread pointer to a register.
>>
>> Tested on x86_64-pc-linux-gnu {,-m32}.
>>
>>> BTW, this x32 TLS IE optimization:
>>
>> > movq %rax, %fs:(%rdx)
>>
>> This is just looking for troubles. If we said these addresses are
>> invalid, then we shouldn't generate them.
>
> OTOH, we can improve rejection test a bit to reject only non-word
> mode registers.
>
> 2012-03-13 Uros Bizjak <ubiz...@gmail.com>
>
> * config/i386/i386.c (ix86_decompose_address): Prevent %fs:(%reg)
> addresses only when %reg is not in word mode.
>
> Tested on x86_64-pc-linux-gnu {,-m32}, committed.
>
> Uros.
>
> Index: i386.c
> ===================================================================
> --- i386.c (revision 185278)
> +++ i386.c (working copy)
> @@ -11563,8 +11563,10 @@
> return 0;
> }
>
> - if (seg != SEG_DEFAULT && (base || index)
> - && !TARGET_TLS_INDIRECT_SEG_REFS)
> +/* Address override works only on the (%reg) part of %fs:(%reg). */
> + if (seg != SEG_DEFAULT
> + && ((base && GET_MODE (base) != word_mode)
> + || (index && GET_MODE (index) != word_mode)))
> return 0;
>
> /* Extract the integral value of scale. */
This works.
--
H.J.
