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16-byte align

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rsc 2006-04-22 00:50:08 +00:00
parent d9ed72433f
commit fa07e3d777
1 changed files with 9 additions and 0 deletions
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9
src/libthread/Darwin-386.c
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@ -3,10 +3,19 @@
void void
makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...) makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
{ {
int n;
int *sp; int *sp;
sp = (int*)ucp->uc_stack.ss_sp+ucp->uc_stack.ss_size/4; sp = (int*)ucp->uc_stack.ss_sp+ucp->uc_stack.ss_size/4;
sp -= argc; sp -= argc;
/*
* Stack pointer at call instruction (before return address
* gets pushed) must be 16-byte aligned.
*/
if((uintptr)sp%4)
abort();
while((uintptr)sp%16)
sp--;
memmove(sp, &argc+1, argc*sizeof(int)); memmove(sp, &argc+1, argc*sizeof(int));
*--sp = 0; /* return address */ *--sp = 0; /* return address */
ucp->uc_mcontext.mc_eip = (long)func; ucp->uc_mcontext.mc_eip = (long)func;