PING.
On Sun, Jul 10, 2011 at 12:43 PM, H.J. Lu <hjl.to...@gmail.com> wrote:
> On Sun, Jul 10, 2011 at 7:32 AM, Uros Bizjak <ubiz...@gmail.com> wrote:
>> On Sat, Jul 9, 2011 at 11:28 PM, H.J. Lu <hongjiu...@intel.com> wrote:
>>
>>> X32 psABI requires promoting pointers to Pmode when passing/returning
>>> in registers. OK for trunk?
>>>
>>> Thanks.
>>>
>>> H.J.
>>> --
>>> 2011-07-09 H.J. Lu <hongjiu...@intel.com>
>>>
>>> * config/i386/i386.c (ix86_promote_function_mode): New.
>>> (TARGET_PROMOTE_FUNCTION_MODE): Likewise.
>>>
>>> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
>>> index 04cb07d..c852719 100644
>>> --- a/gcc/config/i386/i386.c
>>> +++ b/gcc/config/i386/i386.c
>>> @@ -7052,6 +7061,23 @@ ix86_function_value (const_tree valtype, const_tree
>>> fntype_or_decl,
>>> return ix86_function_value_1 (valtype, fntype_or_decl, orig_mode, mode);
>>> }
>>>
>>> +/* Pointer function arguments and return values are promoted to
>>> + Pmode. */
>>> +
>>> +static enum machine_mode
>>> +ix86_promote_function_mode (const_tree type, enum machine_mode mode,
>>> + int *punsignedp, const_tree fntype,
>>> + int for_return)
>>> +{
>>> + if (for_return != 1 && type != NULL_TREE && POINTER_TYPE_P (type))
>>> + {
>>> + *punsignedp = POINTERS_EXTEND_UNSIGNED;
>>> + return Pmode;
>>> + }
>>> + return default_promote_function_mode (type, mode, punsignedp, fntype,
>>> + for_return);
>>> +}
>>
>> Please rewrite the condition to:
>>
>> if (for_return == 1)
>> /* Do not promote function return values. */
>> ;
>> else if (type != NULL_TREE && ...)
>>
>> Also, please add some comments.
>>
>> Your comment also says that pointer return arguments are promoted to
>> Pmode. The documentation says that:
>>
>> FOR_RETURN allows to distinguish the promotion of arguments and
>> return values. If it is `1', a return value is being promoted and
>> `TARGET_FUNCTION_VALUE' must perform the same promotions done here.
>> If it is `2', the returned mode should be that of the register in
>> which an incoming parameter is copied, or the outgoing result is
>> computed; then the hook should return the same mode as
>> `promote_mode', though the signedness may be different.
>>
>> You bypass promotions when FOR_RETURN is 1.
>>
>> Uros.
>>
>
> Here is the updated patch. OK for trunk?
>
> Thanks.
>
> --
> H.J.
> --
> 2011-07-10 H.J. Lu <hongjiu...@intel.com>
>
> * config/i386/i386.c (ix86_promote_function_mode): New.
> (TARGET_PROMOTE_FUNCTION_MODE): Likewise.
>
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index 04cb07d..1b02312 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -7052,6 +7061,27 @@ ix86_function_value (const_tree valtype,
> const_tree fntype_or_decl,
> return ix86_function_value_1 (valtype, fntype_or_decl, orig_mode, mode);
> }
>
> +/* Pointer function arguments and return values are promoted to Pmode.
> + If FOR_RETURN is 1, this function must behave in the same way with
> + regard to function returns as TARGET_FUNCTION_VALUE. */
> +
> +static enum machine_mode
> +ix86_promote_function_mode (const_tree type, enum machine_mode mode,
> + int *punsignedp, const_tree fntype,
> + int for_return)
> +{
> + if (for_return == 1)
> + /* Do not promote function return values. */
> + ;
> + else if (type != NULL_TREE && POINTER_TYPE_P (type))
> + {
> + *punsignedp = POINTERS_EXTEND_UNSIGNED;
> + return Pmode;
> + }
> + return default_promote_function_mode (type, mode, punsignedp, fntype,
> + for_return);
> +}
> +
> rtx
> ix86_libcall_value (enum machine_mode mode)
> {
> @@ -34810,6 +35157,9 @@ ix86_autovectorize_vector_sizes (void)
> #undef TARGET_FUNCTION_VALUE_REGNO_P
> #define TARGET_FUNCTION_VALUE_REGNO_P ix86_function_value_regno_p
>
> +#undef TARGET_PROMOTE_FUNCTION_MODE
> +#define TARGET_PROMOTE_FUNCTION_MODE ix86_promote_function_mode
> +
> #undef TARGET_SECONDARY_RELOAD
> #define TARGET_SECONDARY_RELOAD ix86_secondary_reload
>
--
H.J.
