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#include "all.h"
char *gasloc, *gassym;
static int gasasm;
void
gasinit(enum Asm asmmode)
{
gasasm = asmmode;
switch (gasasm) {
case Gaself:
gasloc = ".L";
gassym = "";
break;
case Gasmacho:
gasloc = "L";
gassym = "_";
break;
}
}
void
gasemitlnk(char *n, Lnk *l, char *s, FILE *f)
{
char *p;
if (l->sec) {
fprintf(f, ".section %s", l->sec);
if (l->secf)
fprintf(f, ", %s", l->secf);
} else {
fputs(s, f);
}
fputc('\n', f);
if (l->align)
fprintf(f, ".balign %d\n", l->align);
p = n[0] == '"' ? "" : gassym;
if (l->export)
fprintf(f, ".globl %s%s\n", p, n);
fprintf(f, "%s%s:\n", p, n);
}
void
gasemitfntail(char *fn, FILE *f)
{
if (gasasm == Gaself) {
fprintf(f, ".type %s, @function\n", fn);
fprintf(f, ".size %s, .-%s\n", fn, fn);
}
}
void
gasemitdat(Dat *d, FILE *f)
{
static char *dtoa[] = {
[DB] = "\t.byte",
[DH] = "\t.short",
[DW] = "\t.int",
[DL] = "\t.quad"
};
static int64_t zero;
char *p;
switch (d->type) {
case DStart:
zero = 0;
break;
case DEnd:
if (zero != -1) {
gasemitlnk(d->name, d->lnk, ".bss", f);
fprintf(f, "\t.fill %"PRId64",1,0\n", zero);
}
break;
case DZ:
if (zero != -1)
zero += d->u.num;
else
fprintf(f, "\t.fill %"PRId64",1,0\n", d->u.num);
break;
default:
if (zero != -1) {
gasemitlnk(d->name, d->lnk, ".data", f);
if (zero > 0)
fprintf(f, "\t.fill %"PRId64",1,0\n", zero);
zero = -1;
}
if (d->isstr) {
if (d->type != DB)
err("strings only supported for 'b' currently");
fprintf(f, "\t.ascii %s\n", d->u.str);
}
else if (d->isref) {
p = d->u.ref.name[0] == '"' ? "" : gassym;
fprintf(f, "%s %s%s%+"PRId64"\n",
dtoa[d->type], p, d->u.ref.name,
d->u.ref.off);
}
else {
fprintf(f, "%s %"PRId64"\n",
dtoa[d->type], d->u.num);
}
break;
}
}
typedef struct Asmbits Asmbits;
struct Asmbits {
char bits[16];
int size;
Asmbits *link;
};
static Asmbits *stash;
int
gasstash(void *bits, int size)
{
Asmbits **pb, *b;
int i;
assert(size == 4 || size == 8 || size == 16);
for (pb=&stash, i=0; (b=*pb); pb=&b->link, i++)
if (size <= b->size)
if (memcmp(bits, b->bits, size) == 0)
return i;
b = emalloc(sizeof *b);
memcpy(b->bits, bits, size);
b->size = size;
b->link = 0;
*pb = b;
return i;
}
void
gasemitfin(FILE *f)
{
Asmbits *b;
char *p;
int sz, i;
double d;
if (gasasm == Gaself)
fprintf(f, ".section .note.GNU-stack,\"\",@progbits\n\n");
if (!stash)
return;
fprintf(f, "/* floating point constants */\n.data\n");
for (sz=16; sz>=4; sz/=2)
for (b=stash, i=0; b; b=b->link, i++) {
if (b->size == sz) {
fprintf(f,
".balign %d\n"
"%sfp%d:",
sz, gasloc, i
);
for (p=b->bits; p<&b->bits[sz]; p+=4)
fprintf(f, "\n\t.int %"PRId32,
*(int32_t *)p);
if (sz <= 8) {
if (sz == 4)
d = *(float *)b->bits;
else
d = *(double *)b->bits;
fprintf(f, " /* %f */\n", d);
} else
fprintf(f, "\n");
}
}
while ((b=stash)) {
stash = b->link;
free(b);
}
}
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