__align_down
pcb = (struct pcb *)__align_down(td_kstack_top(td) - sizeof(struct pcb),
thread0.td_pcb = (struct pcb *)__align_down(td_kstack_top(&thread0) -
va = __align_down(va, dcache_line_size);
va = __align_down(va, dcache_line_size);
va = __align_down(va, dcache_line_size);
register char *t0 __asm("t0") = __align_down(va, dcache_line_size);
register char *t0 __asm("t0") = __align_down(va, dcache_line_size);
register char *t0 __asm("t0") = __align_down(va, dcache_line_size);
#define rounddown2(x, y) __align_down(x, y) /* if y is power of two */
#define STACKALIGN(p) (__align_down(p, STACKALIGNBYTES + 1))