Andrew Pinski wrote:
> On Fri, Oct 10, 2008 at 11:14 AM, Andrew Haley <[EMAIL PROTECTED]> wrote:
>> Richard Guenther wrote:
>>> On Fri, Oct 10, 2008 at 7:55 PM, Andrew Haley <[EMAIL PROTECTED]> wrote:
>>>> I have some broken code, compiled from Java source.
>>>>
>>>> It looks like:
>>>>
>>>> D.843 = &java.text.Collator.class$$;
>>>> _Jv_InitClass (D.843);
>>>> D.845 = &_CD_java_text_Collator;
>>>>
>>>> is being turned into:
>>>>
>>>> D.843 = &java.text.Collator.class$$;
>>>> D.845 = &_CD_java_text_Collator;
>>>> _Jv_InitClass (D.843);
>>> This is always a valid transformation.
>>>
>>>> i.e. the memory reference is moved to before the call to _Jv_InitClass.
>>> There is no memory reference in the above case, it seems just the address
>>> of _CD_java_text_Collator is taken.
>>>
>>> Or maybe I'm missing sth?
>> In the RTL code it moves the mem ref, not just the address:
>>
>> (call (mem:QI (symbol_ref:DI ("_Jv_InitClass") [flags 0x41]
>>
>> (set (reg/f:DI 95 [ #ref#8#1 ])
>> (mem/s/u/f/j:DI (const:DI (plus:DI (symbol_ref:DI
>> ("_CD_java_text_Collator")
>> (const_int 16 [0x10])))
>>
>> is turned to:
>>
>> (set (reg/f:DI 162 [ #ref#8#1 ])
>> (mem/s/u/f/j:DI (const:DI (plus:DI (symbol_ref:DI
>> ("_CD_java_text_Collator")
>> (const_int 16 [0x10])))
>>
>> ...
>>
>> (call (mem:QI (symbol_ref:DI ("_Jv_InitClass")
>
> Well the mem has a /u on it so it is being marked as MEM_READONLY_P so
> it is valid optimization. Why it is being marked with MEM_READONLY_P,
> I don't know.
Thanks to everyone who responded. I hadn't noticed the /u on the mem.
I'll find out why it's marked readonly -- it's probably a FE bug.
Thanks,
Andrew.
