ack/mach/m68k2/cg/mach.c
1987-12-02 09:04:32 +00:00

319 lines
5.7 KiB
C

#ifndef NORCSID
static char rcsid[] = "$Header$";
#endif
/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*
*/
/*
* machine dependent back end routines for the Motorola 68000
*/
#include "fppsim.h"
con_part(sz,w) register sz; word w; {
while (part_size % sz)
part_size++;
if (part_size == TEM_WSIZE)
part_flush();
if (sz == 1) {
w &= 0xFF;
if (part_size == 0)
w <<= 8;
part_word |= w;
} else {
assert(sz == 2);
part_word = w;
}
part_size += sz;
}
con_mult(sz) word sz; {
if (sz != 4)
fatal("bad icon/ucon size");
fprintf(codefile,".data4 %s\n",str);
}
#ifdef NOFLOAT
con_float() {
static int been_here;
if (argval != 4 && argval != 8)
fatal("bad fcon size");
fputs(".data4\t", codefile);
if (argval == 8)
fputs("0,", codefile);
fputs("0 !dummy float\n", codefile);
if ( !been_here++)
{
fputs("Warning : dummy float-constant(s)\n", stderr);
}
}
#else
#define IEEEFLOAT
con_float() {
double f;
double atof();
float fl;
int i;
#ifndef OWNFLOAT
double f1;
double frexp(), modf();
int j;
int sign = 0;
int fraction[4] ;
#else OWNFLOAT
char *p;
#endif OWNFLOAT
if (argval!= 4 && argval!= 8) {
fprintf(stderr,"float constant size = %d\n",argval);
fatal("bad fcon size");
}
fprintf(codefile,"!float %s sz %d\n", str, argval);
f = atof(str);
#ifdef OWNFLOAT
if (argval == 4) {
fl = f;
p = (char *) &fl;
}
else {
p = (char *) &f;
}
fprintf(codefile, ".data1 0%o", *p++ & 0377);
for (i = argval-1; i; i--) {
fprintf(codefile,",0%o", *p++ & 0377);
}
#else OWNFLOAT
f = frexp(f, &i);
if (f < 0) {
f = -f;
sign = 1;
}
if (f == 0) {
if (argval == 8) fprintf(codefile, ".data2 0, 0\n");
fprintf(codefile, ".data2 0, 0\n");
return;
}
while (f < 0.5) {
f += f;
i --;
}
f = modf(2 * f, &f1); /* hidden bit */
#ifdef IEEEFLOAT
if (argval == 4) {
#endif IEEEFLOAT
i = (i + 128) & 0377;
fraction[0] = (sign << 15) | (i << 7);
for (j = 6; j>= 0; j--) {
if (f >= 0.5) fraction[0] |= (1 << j);
f = modf(2*f, &f1);
}
#ifdef IEEEFLOAT
}
else {
i = (i + 1024) & 03777;
fraction[0] = (sign << 15) | (i << 4);
for (j = 3; j>= 0; j--) {
if (f >= 0.5) fraction[0] |= (1 << j);
f = modf(2*f, &f1);
}
}
#endif IEEEFLOAT
for (i = 1; i < argval / 2; i++) {
fraction[i] = 0;
for (j = 15; j>= 0; j--) {
if (f >= 0.5) fraction[i] |= (1 << j);
f = modf(2*f, &f1);
}
}
if (f >= 0.5) {
for (i = argval/2 - 1; i >= 0; i--) {
for (j = 0; j < 16; j++) {
if (fraction[i] & (1 << j)) {
fraction[i] &= ~(1 << j);
}
else {
fraction[i] |= (1 << j);
break;
}
}
if (j != 16) break;
}
}
for (i = 0; i < argval/2; i++) {
fprintf(codefile,
i != 0 ? ", 0%o, 0%o" : ".data1 0%o, 0%o",
(fraction[i]>>8)&0377,
fraction[i]&0377);
}
#endif OWNFLOAT
putc('\n', codefile);
}
#endif
#ifdef REGVARS
regscore(off,size,typ,score,totyp)
long off;
{
if (score == 0) return -1;
switch(typ) {
case reg_float:
return -1;
case reg_pointer:
if (size != 4 || totyp != reg_pointer) return -1;
score *= 2;
break;
case reg_loop:
score += 5;
/* fall through .. */
case reg_any:
if (size != 2 || totyp == reg_pointer) return -1;
break;
}
if (off >= 0) {
/* parameters must be initialised with an instruction
* like "move.w 4(a6),d0", which costs 2 words.
*/
score -= 2;
}
score -= 1; /* take save/restore into account */
return score;
}
struct regsav_t {
char *rs_reg; /* e.g. "a3" or "d5" */
long rs_off; /* offset of variable */
int rs_size; /* 2 or 4 bytes */
} regsav[9];
int regnr;
i_regsave()
{
regnr = 0;
}
#define MOVEM_LIMIT 2
/* If #registers to be saved exceeds MOVEM_LIMIT, we
* use the movem instruction to save registers; else
* we simply use several move.l's.
*/
save()
{
register struct regsav_t *p;
if (regnr > MOVEM_LIMIT) {
fprintf(codefile,"movem.l ");
for (p = regsav; ;) {
fprintf(codefile,"%s",p->rs_reg);
if (++p == &regsav[regnr]) break;
putc('/',codefile);
}
fprintf(codefile,",-(sp)\n");
} else {
for (p = regsav; p < &regsav[regnr]; p++) {
fprintf(codefile,"move.l %s,-(sp)\n",p->rs_reg);
}
}
/* initialise register-parameters */
for (p = regsav; p < &regsav[regnr]; p++) {
if (p->rs_off >= 0) {
fprintf(codefile,"move.%c %ld(a6),%s\n",
(p->rs_size == 4 ? 'l' : 'w'),
p->rs_off,
p->rs_reg);
}
}
}
restr()
{
register struct regsav_t *p;
if (regnr > MOVEM_LIMIT) {
fprintf(codefile,"movem.l (sp)+,");
for (p = regsav; ;) {
fprintf(codefile,"%s",p->rs_reg);
if (++p == &regsav[regnr]) break;
putc('/',codefile);
}
putc('\n',codefile);
} else {
for (p = &regsav[regnr-1]; p >= regsav; p--) {
fprintf(codefile,"move.l (sp)+,%s\n",p->rs_reg);
}
}
fprintf(codefile,"unlk a6\n");
fprintf(codefile,"rts\n");
}
f_regsave()
{
save();
}
regsave(str,off,size)
char *str;
long off;
{
assert (regnr < 9);
regsav[regnr].rs_reg = str;
regsav[regnr].rs_off = off;
regsav[regnr++].rs_size = size;
fprintf(codefile, "!Local %ld into %s\n",off,str);
}
regreturn()
{
restr();
}
#endif
prolog(nlocals) full nlocals; {
fprintf(codefile,"tst.b -%ld(sp)\nlink\ta6,#-%ld\n",nlocals+40,nlocals);
}
mes(type) word type ; {
int argt ;
switch ( (int)type ) {
case ms_ext :
for (;;) {
switch ( argt=getarg(
ptyp(sp_cend)|ptyp(sp_pnam)|sym_ptyp) ) {
case sp_cend :
return ;
default:
strarg(argt) ;
fprintf(codefile,".define %s\n",argstr) ;
break ;
}
}
default :
while ( getarg(any_ptyp) != sp_cend ) ;
break ;
}
}
char *segname[] = {
".sect .text", /* SEGTXT */
".sect .data", /* SEGCON */
".sect .rom", /* SEGROM */
".sect .bss" /* SEGBSS */
};