#ifndef _avcall_arm_c /*-*- C -*-*/
#define _avcall_arm_c
/**
Copyright 1993 Bill Triggs, <Bill.Triggs@inrialpes.fr>
Copyright 1995-1999 Bruno Haible, <bruno@clisp.org>
This is free software distributed under the GNU General Public
Licence described in the file COPYING. Contact the author if
you don't have this or can't live with it. There is ABSOLUTELY
NO WARRANTY, explicit or implied, on this software.
**/
/*----------------------------------------------------------------------
!!! THIS ROUTINE MUST BE COMPILED gcc -O !!!
Foreign function interface for an Acorn Risc Maschine with gcc.
This calls a C function with an argument list built up using macros
defined in av_call.h.
ARM Argument Passing Conventions:
All arguments, except the first 4 words, are passed on the stack with
word alignment. Doubles take two words. Structure args are passed as
true structures embedded in the argument stack. To return a structure,
the called function copies the return value to the address supplied
in register "%r0".
Compile this routine with gcc -O (or -O2 or -g -O) to get the right
register variables, or use the assembler version.
----------------------------------------------------------------------*/
#include "avcall.h.in"
#define RETURN(TYPE,VAL) (*(TYPE*)l->raddr = (TYPE)(VAL))
int
__builtin_avcall(av_alist* l)
{
register __avword* sp __asm__("r13"); /* C names for registers */
/*register __avword iret __asm__("r0"); */
register __avword iret2 __asm__("r1");
register float fret __asm__("r0"); /* r0 */
register double dret __asm__("r0"); /* r0,r1 */
__avword space[__AV_ALIST_WORDS]; /* space for callee's stack frame */
__avword* argframe = sp; /* stack offset for argument list */
int arglen = l->aptr - l->args;
__avword i;
for (i = 4; i < arglen; i++) /* push function args onto stack */
argframe[i-4] = l->args[i];
/* call function, pass 4 args in registers */
i = (*l->func)(l->args[0], l->args[1], l->args[2], l->args[3]);
/* save return value */
if (l->rtype == __AVvoid) {
} else
if (l->rtype == __AVword) {
RETURN(__avword, i);
} else
if (l->rtype == __AVchar) {
RETURN(char, i);
} else
if (l->rtype == __AVschar) {
RETURN(signed char, i);
} else
if (l->rtype == __AVuchar) {
RETURN(unsigned char, i);
} else
if (l->rtype == __AVshort) {
RETURN(short, i);
} else
if (l->rtype == __AVushort) {
RETURN(unsigned short, i);
} else
if (l->rtype == __AVint) {
RETURN(int, i);
} else
if (l->rtype == __AVuint) {
RETURN(unsigned int, i);
} else
if (l->rtype == __AVlong) {
RETURN(long, i);
} else
if (l->rtype == __AVulong) {
RETURN(unsigned long, i);
} else
if (l->rtype == __AVlonglong || l->rtype == __AVulonglong) {
((__avword*)l->raddr)[0] = i;
((__avword*)l->raddr)[1] = iret2;
} else
if (l->rtype == __AVfloat) {
RETURN(float, fret);
} else
if (l->rtype == __AVdouble) {
RETURN(double, dret);
} else
if (l->rtype == __AVvoidp) {
RETURN(void*, i);
} else
if (l->rtype == __AVstruct) {
/* PCS for ARM (http://infocenter.arm.com/help/topic/com.arm.doc.ihi0042b/IHI0042B_aapcs.pdf):
page 19: "A Composite Type not larger than 4 bytes is returned in r0."
sizeof({char a[3];}) = 3, so we have to use <= sizeof below */
if (l->flags & __AV_PCC_STRUCT_RETURN) {
/* pcc struct return convention: need a *(TYPE*)l->raddr = *(TYPE*)i; */
if (l->rsize == sizeof(char)) { /* can't occur */
RETURN(char, *(char*)i);
} else
if (l->rsize == sizeof(short)) { /* can't occur */
RETURN(short, *(short*)i);
} else
if (l->rsize <= sizeof(int)) { /* structs of size 3 also returned in registers */
RETURN(int, *(int*)i);
} else
if (l->rsize == sizeof(double)) {
((int*)l->raddr)[0] = ((int*)i)[0];
((int*)l->raddr)[1] = ((int*)i)[1];
} else {
int n = (l->rsize+3)/4;
while (--n >= 0)
((__avword*)l->raddr)[n] = ((__avword*)i)[n];
}
} else {
/* normal struct return convention */
if (l->flags & __AV_REGISTER_STRUCT_RETURN) {
if (l->rsize == sizeof(char)) { /* can't occur */
RETURN(char, i);
} else
if (l->rsize == sizeof(short)) { /* can't occur */
RETURN(short, i);
} else
if (l->rsize <= sizeof(int)) {
RETURN(int, i);
} else
if (l->rsize == 2*sizeof(__avword)) {
((__avword*)l->raddr)[0] = i;
((__avword*)l->raddr)[1] = iret2;
}
}
}
}
return 0;
}
#endif /*_avcall_arm_c */