On Tue, Sep 16, 2014 at 11:37 AM, Ilya Enkovich <enkovich....@gmail.com> wrote:
> 2014-09-16 13:08 GMT+04:00 Uros Bizjak <ubiz...@gmail.com>:
>> Hello!
>>
>>> This patch adds size relocation support for i386 target. Relocation is
>>> used to compute bounds for static objects with incomplete type.
>>>
>>> Thanks,
>>> Ilya
>>> --
>>> gcc/
>>>
>>> 2014-06-11 Ilya Enkovich <ilya.enkov...@intel.com>
>>>
>>> * config/i386/i386.md (UNSPEC_SIZEOF): New.
>>> (move_size_reloc_si): New.
>>> (move_size_reloc_di): New.
>>> * config/i386/predicates.md (symbol_operand): New.
>>>
>>>
>>> diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
>>> index 32db2c6..5fd556b 100644
>>> --- a/gcc/config/i386/i386.md
>>> +++ b/gcc/config/i386/i386.md
>>> @@ -79,6 +79,7 @@
>>> UNSPEC_PLTOFF
>>> UNSPEC_MACHOPIC_OFFSET
>>> UNSPEC_PCREL
>>> + UNSPEC_SIZEOF
>>>
>>> ;; Prologue support
>>> UNSPEC_STACK_ALLOC
>>> @@ -18340,6 +18341,32 @@
>>> "bndstx\t{%2, %3|%3, %2}"
>>> [(set_attr "type" "mpxst")])
>>>
>>> +(define_insn "move_size_reloc_si"
>>> + [(set (match_operand:SI 0 "register_operand" "=r")
>>> + (unspec:SI
>>> + [(match_operand:SI 1 "symbol_operand")]
>>> + UNSPEC_SIZEOF))]
>>> + "TARGET_MPX"
>>> + "mov{l}\t{%1@SIZE, %0|%0, %1@SIZE}"
>>> + [(set_attr "type" "imov")
>>> + (set_attr "mode" "SI")])
>>> +
>>> +(define_insn "move_size_reloc_di"
>>> + [(set (match_operand:DI 0 "register_operand" "=r")
>>> + (unspec:DI
>>> + [(match_operand:DI 1 "symbol_operand")]
>>> + UNSPEC_SIZEOF))]
>>> + "TARGET_64BIT && TARGET_MPX"
>>> +{
>>> + if (ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_LARGE
>>> + || ix86_cmodel == CM_MEDIUM_PIC || ix86_cmodel == CM_LARGE_PIC)
>>> + return "movabs{q}\t{%1@SIZE, %0|%0, %1@SIZE}";
>>
>> Can x86_64_immediate_operand predicate be used here?
>
> I think it cannot be used because of TLS symbols not counting as immediate.
OK, please introduce a new predicate, similar to
x86_64_immediate_operand, perhaps x86_64_immediate_size_operand, so we
can add some comments there. This will also help to macroize the insn,
x86_64_immediate_operand has !TARGET_64BIT shortcut for this case.
Uros.
