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SubjectRe: [patch 4/21] fix ARCH_HAS_PREFETCH
On Wed, Aug 14, 2002 at 01:58:41PM -0700, H. Peter Anvin wrote:
> Willy Tarreau wrote:
> > This way, some loops could be optimized, and the developpers could explicitely
> > tell the compiler when they need to prevent any optimization.
> >
>
> #define __nop() asm volatile("")

and if you want to pass arguments, to guarantee that no optimization will
be done, even on loop constants ?
eg:
for (i = 0; i < N; i++) {
j++;
__nop();
}

-> might be optimized this way :
j = N;
for (i = 0; i < N; i++) {
__nop();
}

Perhaps using a volatile for j ?

Cheers,
Willy

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