On Wed, Jan 22, 2014 at 2:02 PM, H.J. Lu <hjl.to...@gmail.com> wrote:
> On Mon, Jan 20, 2014 at 1:11 AM, Uros Bizjak <ubiz...@gmail.com> wrote:
>> On Mon, Jan 20, 2014 at 9:38 AM, Jakub Jelinek <ja...@redhat.com> wrote:
>>
>>> As mentioned in the PR or even in the comment below, ix86_decompose_address
>>> sometimes sets parts.base to some REG and parts.disp to const0_rtx, even
>>> when the operands aren't of a lea insn, but normal or zero extending mov.
>>>
>>> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
>>> trunk?
>>>
>>> 2014-01-20 Jakub Jelinek <ja...@redhat.com>
>>>
>>> PR target/59880
>>> * config/i386/i386.c (ix86_avoid_lea_for_addr): Return false
>>> if operands[1] is a REG or ZERO_EXTEND of a REG.
>>>
>>> * gcc.target/i386/pr59880.c: New test.
>>
>>> --- gcc/config/i386/i386.c.jj 2014-01-19 12:18:49.000000000 +0100
>>> +++ gcc/config/i386/i386.c 2014-01-19 19:02:34.078168289 +0100
>>> @@ -18159,8 +18159,19 @@ ix86_avoid_lea_for_addr (rtx insn, rtx o
>>> if (!TARGET_AVOID_LEA_FOR_ADDR || optimize_function_for_size_p (cfun))
>>> return false;
>>>
>>> + /* The "at least two components" test below might not catch simple
>>> + *mov[sd]i_internal or *zero_extendsidi2 insns if parts.base is
>>> + non-NULL and parts.disp is const0_rtx as the only components in
>>> + the address, e.g. if the register is %rbp or %r13. As this
>>> + test is much cheaper and moves or zero extensions are the common
>>> + case, do this check first. */
>>> + if (REG_P (operands[1])
>>> + || (GET_CODE (operands[1]) == ZERO_EXTEND
>>> + && REG_P (XEXP (operands[1], 0))))
>>> + return false;
>>> +
>>> /* Check it is correct to split here. */
>>> - if (!ix86_ok_to_clobber_flags(insn))
>>> + if (!ix86_ok_to_clobber_flags (insn))
>>> return false;
>>>
>>> ok = ix86_decompose_address (operands[1], &parts);
>>> --- gcc/testsuite/gcc.target/i386/pr59880.c.jj 2014-01-19
>>> 19:24:44.094382629 +0100
>>> +++ gcc/testsuite/gcc.target/i386/pr59880.c 2014-01-19
>>> 19:25:30.000000000 +0100
>>> @@ -0,0 +1,14 @@
>>> +/* PR target/59880 */
>>> +/* { dg-do compile { target { ! ia32 } } } */
>>> +/* { dg-options "-O2 -mtune=silvermont" } */
>>> +
>>> +register unsigned int r13 __asm ("r13");
>>> +unsigned long long
>>> +foo (void)
>>> +{
>>> + return r13;
>>> +}
>>> +
>>> +/* Ensure we don't emit a useless zero-extension after another
>>> + zero-extension. */
>>> +/* { dg-final { scan-assembler-not "%eax, %eax" } } */
>>>
>>> Jakub
>>
>> This is OK for mainline, I will take care for a backport (together
>> with 59379) to other release branches.
>>
>
> I backported gcc.target/i386/pr59880.c to 4.8 branch by
> replacing -mtune=silvermont with -mtune=slm.
>
> Thanks.
>
> --
> H.J.
> --
> Index: ChangeLog
> ===================================================================
> --- ChangeLog (revision 206941)
> +++ ChangeLog (working copy)
> @@ -1,3 +1,11 @@
> +2014-01-22 H.J. Lu <hongjiu...@intel.com>
> +
> + Backport from mainline
> + 2014-01-20 Jakub Jelinek <ja...@redhat.com>
> +
> + PR target/59880
> + * gcc.target/i386/pr59880.c: New test.
> +
> 2014-01-21 Jakub Jelinek <ja...@redhat.com>
>
> PR middle-end/59860
> Index: gcc.target/i386/pr59880.c
> ===================================================================
> --- gcc.target/i386/pr59880.c (revision 0)
> +++ gcc.target/i386/pr59880.c (working copy)
> @@ -0,0 +1,14 @@
> +/* PR target/59880 */
> +/* { dg-do compile { target { ! ia32 } } } */
> +/* { dg-options "-O2 -mtune=slm" } */
> +
> +register unsigned int r13 __asm ("r13");
> +unsigned long long
> +foo (void)
> +{
> + return r13;
> +}
> +
> +/* Ensure we don't emit a useless zero-extension after another
> + zero-extension. */
> +/* { dg-final { scan-assembler-not "%eax, %eax" } } */
I tested it on the wrong branch. -mtune=slm doesn't exist
on 4.8 branch. I reverted. Sorry for it.
--
H.J.
