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SubjectRe: [PATCH 4.19 079/271] x86/atomic: Fix smp_mb__{before,after}_atomic()
On 7/26/19, Peter Zijlstra <peterz@infradead.org> wrote:
> On Fri, Jul 26, 2019 at 01:18:06PM +0300, Jari Ruusu wrote:
>> Shouldn't those clobber contraints actually be: "memory","cc"
>> That is because addl subl (and other) machine instructions
>> actually modify the flags register too.
>>
>> gcc docs say: The "cc" clobber indicates that the assembler
>> code modifies the flags register.
>
> GCC x86 assumes any asm() will clobber "cc".

No worries then. Thanks for your clarification.

--
Jari Ruusu 4096R/8132F189 12D6 4C3A DCDA 0AA4 27BD ACDF F073 3C80 8132 F189

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