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

[Michael Ellerman]

Christophe Leroy <christophe.leroy@xxxxxxxxxx> 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