Messages in this thread | | | Date | Fri, 9 Aug 2002 01:04:40 +0200 (CEST) | From | Roman Zippel <> | Subject | Re: [PATCH] [2.5] asm-generic/atomic.h and changes to arm, parisc, mips, m68k, sh, cris to use it |
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Hi,
On 9 Aug 2002, Luca Barbieri wrote:
> > The compiler can cache the value in a register > It shouldn't since it is volatile and the machine has instructions with > memory operands.
volatile is no guarantee for that:
volatile int x;
void f(int y) { x += y; }
becomes:
move.l x,%d0 add.l 8(%a6),%d0 move.l %d0,x
I agree that volatile should avoid caching, but it does not guarantee an atomic modify.
bye, Roman
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