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SubjectRe: [PATCH 2/3] powerpc/module32: Use symbolic instructions names.
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Le 29/04/2019 à 13:54, Segher Boessenkool a écrit :
> On Mon, Apr 29, 2019 at 10:43:27AM +0000, Christophe Leroy wrote:
>> To increase readability/maintainability, replace hard coded
>> instructions values by symbolic names.
>
>> + /* lis r12,sym@ha */
>> +#define ENTRY_JMP0(sym) (PPC_INST_ADDIS | __PPC_RT(R12) | PPC_HA(sym))
>> + /* addi r12,r12,sym@l */
>> +#define ENTRY_JMP1(sym) (PPC_INST_ADDI | __PPC_RT(R12) | __PPC_RA(R12) | PPC_LO(sym))
>
> Those aren't "jump" instructions though, as the name suggests... And you
> only have names for the first two of the four insns. ("2" and "3" were
> still available ;-) )

Well, the idea was to say they are defining the jump destination.
Anyway, as they are used only once, let's put it directly in.

>
>> - entry->jump[0] = 0x3d800000+((val+0x8000)>>16); /* lis r12,sym@ha */
>> - entry->jump[1] = 0x398c0000 + (val&0xffff); /* addi r12,r12,sym@l*/
>> - entry->jump[2] = 0x7d8903a6; /* mtctr r12 */
>> - entry->jump[3] = 0x4e800420; /* bctr */
>> + entry->jump[0] = ENTRY_JMP0(val);
>> + entry->jump[1] = ENTRY_JMP1(val);
>> + entry->jump[2] = PPC_INST_MTCTR | __PPC_RS(R12);
>> + entry->jump[3] = PPC_INST_BCTR;
>
> Deleting the comment here is not an improvement imo.

Ok, I'll leave them in as I did for module64

Christophe

>
>
> Segher
>

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