16-byte align

This commit is contained in:
rsc 2006-04-22 00:50:08 +00:00
parent d9ed72433f
commit fa07e3d777

View file

@ -3,10 +3,19 @@
void
makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
{
int n;
int *sp;
sp = (int*)ucp->uc_stack.ss_sp+ucp->uc_stack.ss_size/4;
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));
*--sp = 0; /* return address */
ucp->uc_mcontext.mc_eip = (long)func;