#ifndef _avcall_s390_c /*-*- C -*-*/
#define _avcall_s390_c
/**
Copyright 1993 Bill Triggs, <Bill.Triggs@inrialpes.fr>
Copyright 1995-1999 Bruno Haible, <bruno@clisp.org>
Copyright 2001 Gerhard Tonn, <gt@debian.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.
**/
/*----------------------------------------------------------------------
Foreign function interface for an IBM S/390 with gcc
This calls a C function with an argument list built up using macros
defined in av_call.h.
S390 Argument Passing Conventions:
All arguments, except the first 5 words, are passed on the stack with
word alignment. Doubles take two words. The first 2 doubles and floats
are also passed in floating-point-registers.
To return a structure, the called function copies the value to space
pointed to by its first argument, and all other arguments are shifted
down by one.
Compile this routine with gcc -O2 to get the right register variables.
For other compilers use the pre-compiled assembler version.
----------------------------------------------------------------------*/
#include "avcall.h"
#define STACK_OFFSET 24
#define RETURN(TYPE,VAL) (*(TYPE*)l->raddr = (TYPE)(VAL))
register float farg1 __asm__("f0");
register float farg2 __asm__("f2");
register double darg1 __asm__("f0");
register double darg2 __asm__("f2");
int
__builtin_avcall(av_alist* l)
{
register __avword* sp __asm__("r15"); /* C names for registers */
/*register __avword iret __asm__("r2"); */
register __avword iret2 __asm__("r3");
register float fret __asm__("f0");
register double dret __asm__("f0");
__avword space[__AV_ALIST_WORDS]; /* space for callee's stack frame */
__avword* argframe = sp + STACK_OFFSET;/* stack offset for argument list */
int arglen = l->aptr - l->args;
int farglen = l->faptr - l->fargs;
int iargwords = (arglen-l->fargwords)<5?arglen-l->fargwords:5;
__avword i;
for (i = iargwords; i < arglen; i++) /* push function args onto stack */
argframe[i-iargwords] = l->args[i];
/* pass first 2 floating-point args in registers */
if (farglen == 1) {
if(l->fargsused[0]) farg1 = l->fargs[0]; else darg1 = l->dargs[0];
}
else if (farglen == 2) {
if(l->fargsused[0] && l->fargsused[1]) {
farg1 = l->fargs[0]; farg2 = l->fargs[1];
}
else if(l->fargsused[0] && !l->fargsused[1]) {
farg1 = l->fargs[0]; darg2 = l->dargs[1];
}
else if(!l->fargsused[0] && l->fargsused[1]) {
darg1 = l->dargs[0]; farg2 = l->fargs[1];
}
else if(!l->fargsused[0] && !l->fargsused[1]) {
darg1 = l->dargs[0]; darg2 = l->dargs[1];
}
}
/* call function, pass 5 args in registers */
i = (*l->func)(l->args[0], l->args[1], l->args[2], l->args[3],
l->args[4]);
/* 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) {
if (l->flags & __AV_PCC_STRUCT_RETURN) {
/* pcc struct return convention: need a *(TYPE*)l->raddr = *(TYPE*)i; */
if (l->rsize == sizeof(char)) {
RETURN(char, *(char*)i);
} else
if (l->rsize == sizeof(short)) {
RETURN(short, *(short*)i);
} else
if (l->rsize == sizeof(int)) {
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 + sizeof(__avword)-1)/sizeof(__avword);
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)) {
RETURN(char, i);
} else
if (l->rsize == sizeof(short)) {
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_s390_c */