Messages in this thread |  | | From | Jari Ruusu <> | Date | Fri, 26 Jul 2019 17:07:39 +0300 | Subject | Re: [PATCH 4.19 079/271] x86/atomic: Fix smp_mb__{before,after}_atomic() |
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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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