[PATCH v5 02/16] powerpc: Override __ALIGN and __ALIGN_STR macros

Michael Ellerman mpe at ellerman.id.au
Thu Nov 3 11:01:54 AEDT 2022


Christophe Leroy <christophe.leroy at csgroup.eu> writes:
> Le 28/10/2022 à 16:33, Sathvika Vasireddy a écrit :
>> In a subsequent patch, we would want to annotate powerpc assembly functions
>> with SYM_FUNC_START_LOCAL macro. This macro depends on __ALIGN macro.
>> 
>> The default expansion of __ALIGN macro is:
>>          #define __ALIGN      .align 4,0x90
>> 
>> So, override __ALIGN and __ALIGN_STR macros to use the same alignment as
>> that of the existing _GLOBAL macro. Also, do not pad with 0x90, because
>> repeated 0x90s are not a nop or trap on powerpc.
>
> By the way, do we know what the instruction 0x90909090 is on powerpc ? 
> Is that something valid or not ?

According to objdump it's:

stw     r4,-28528(r16)

cheers


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