usr/src/lib/libc/vax/gen/alloca.s

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)alloca.s    5.1 (Berkeley) %G%";
#endif not lint

/* like alloc, but automatic free in return */

#include "DEFS.h"

ENTRY(alloca, 0)
        subl2   4(ap),sp        /* crude allocation */
        movl    16(fp),r1       /* pc */
        movq    8(fp),ap        /* new (old) ap and fp */
        bicl2   $3,sp           /* 4-byte align */
        addl2   $7*4,sp         /* reuse space of mscp */
        movl    sp,r0           /* return value */
        jmp     (r1)            /* funny return */