ref: 8188b4f4f0e07b6669e6ae3c6c1099af917eaab4
dir: /sys/src/cmd/5c/swt.c/
#include "gc.h"
void
swit1(C1 *q, int nc, long def, Node *n)
{
Node tn;
regalloc(&tn, ®node, Z);
swit2(q, nc, def, n, &tn);
regfree(&tn);
}
void
swit2(C1 *q, int nc, long def, Node *n, Node *tn)
{
C1 *r;
int i;
long v;
Prog *sp;
if(nc >= 3) {
i = (q+nc-1)->val - (q+0)->val;
if(i > 0 && i < nc*2)
goto direct;
}
if(nc < 5) {
for(i=0; i<nc; i++) {
if(debug['W'])
print("case = %.8llux\n", q->val);
gopcode(OEQ, nodconst(q->val), n, Z);
patch(p, q->label);
q++;
}
gbranch(OGOTO);
patch(p, def);
return;
}
i = nc / 2;
r = q+i;
if(debug['W'])
print("case > %.8llux\n", r->val);
gopcode(OGT, nodconst(r->val), n, Z);
sp = p;
gopcode(OEQ, nodconst(r->val), n, Z); /* just gen the B.EQ */
patch(p, r->label);
swit2(q, i, def, n, tn);
if(debug['W'])
print("case < %.8llux\n", r->val);
patch(sp, pc);
swit2(r+1, nc-i-1, def, n, tn);
return;
direct:
v = q->val;
if(v != 0)
gopcode(OSUB, nodconst(v), Z, n);
gopcode(OCASE, nodconst((q+nc-1)->val - v), n, Z);
patch(p, def);
for(i=0; i<nc; i++) {
if(debug['W'])
print("case = %.8llux\n", q->val);
while(q->val != v) {
nextpc();
p->as = ABCASE;
patch(p, def);
v++;
}
nextpc();
p->as = ABCASE;
patch(p, q->label);
q++;
v++;
}
gbranch(OGOTO); /* so that regopt() won't be confused */
patch(p, def);
}
void
bitload(Node *b, Node *n1, Node *n2, Node *n3, Node *nn)
{
int sh;
long v;
Node *l;
/*
* n1 gets adjusted/masked value
* n2 gets address of cell
* n3 gets contents of cell
*/
l = b->left;
if(n2 != Z) {
regalloc(n1, l, nn);
reglcgen(n2, l, Z);
regalloc(n3, l, Z);
gopcode(OAS, n2, Z, n3);
gopcode(OAS, n3, Z, n1);
} else {
regalloc(n1, l, nn);
cgen(l, n1);
}
if(b->type->shift == 0 && typeu[b->type->etype]) {
v = ~0 + (1L << b->type->nbits);
gopcode(OAND, nodconst(v), Z, n1);
} else {
sh = 32 - b->type->shift - b->type->nbits;
if(sh > 0)
gopcode(OASHL, nodconst(sh), Z, n1);
sh += b->type->shift;
if(sh > 0)
if(typeu[b->type->etype])
gopcode(OLSHR, nodconst(sh), Z, n1);
else
gopcode(OASHR, nodconst(sh), Z, n1);
}
}
void
bitstore(Node *b, Node *n1, Node *n2, Node *n3, Node *nn)
{
long v;
Node nod, *l;
int sh;
/*
* n1 has adjusted/masked value
* n2 has address of cell
* n3 has contents of cell
*/
l = b->left;
regalloc(&nod, l, Z);
v = ~0 + (1L << b->type->nbits);
gopcode(OAND, nodconst(v), Z, n1);
gopcode(OAS, n1, Z, &nod);
if(nn != Z)
gopcode(OAS, n1, Z, nn);
sh = b->type->shift;
if(sh > 0)
gopcode(OASHL, nodconst(sh), Z, &nod);
v <<= sh;
gopcode(OAND, nodconst(~v), Z, n3);
gopcode(OOR, n3, Z, &nod);
gopcode(OAS, &nod, Z, n2);
regfree(&nod);
regfree(n1);
regfree(n2);
regfree(n3);
}
long
outstring(char *s, long n)
{
long r;
if(suppress)
return nstring;
r = nstring;
while(n) {
string[mnstring] = *s++;
mnstring++;
nstring++;
if(mnstring >= NSNAME) {
gpseudo(ADATA, symstring, nodconst(0L));
p->from.offset += nstring - NSNAME;
p->reg = NSNAME;
p->to.type = D_SCONST;
memmove(p->to.sval, string, NSNAME);
mnstring = 0;
}
n--;
}
return r;
}
int
mulcon(Node *n, Node *nn)
{
Node *l, *r, nod1, nod2;
Multab *m;
long v, vs;
int o;
char code[sizeof(m->code)+2], *p;
if(typefd[n->type->etype])
return 0;
l = n->left;
r = n->right;
if(l->op == OCONST) {
l = r;
r = n->left;
}
if(r->op != OCONST)
return 0;
v = convvtox(r->vconst, n->type->etype);
if(v != r->vconst) {
if(debug['M'])
print("%L multiply conv: %lld\n", n->lineno, r->vconst);
return 0;
}
m = mulcon0(v);
if(!m) {
if(debug['M'])
print("%L multiply table: %lld\n", n->lineno, r->vconst);
return 0;
}
if(debug['M'] && debug['v'])
print("%L multiply: %ld\n", n->lineno, v);
memmove(code, m->code, sizeof(m->code));
code[sizeof(m->code)] = 0;
p = code;
if(p[1] == 'i')
p += 2;
regalloc(&nod1, n, nn);
cgen(l, &nod1);
vs = v;
regalloc(&nod2, n, Z);
loop:
switch(*p) {
case 0:
regfree(&nod2);
if(vs < 0) {
gopcode(OAS, &nod1, Z, &nod1);
gopcode(OSUB, &nod1, nodconst(0), nn);
} else
gopcode(OAS, &nod1, Z, nn);
regfree(&nod1);
return 1;
case '+':
o = OADD;
goto addsub;
case '-':
o = OSUB;
addsub: /* number is r,n,l */
v = p[1] - '0';
r = &nod1;
if(v&4)
r = &nod2;
n = &nod1;
if(v&2)
n = &nod2;
l = &nod1;
if(v&1)
l = &nod2;
gopcode(o, l, n, r);
break;
default: /* op is shiftcount, number is r,l */
v = p[1] - '0';
r = &nod1;
if(v&2)
r = &nod2;
l = &nod1;
if(v&1)
l = &nod2;
v = *p - 'a';
if(v < 0 || v >= 32) {
diag(n, "mulcon unknown op: %c%c", p[0], p[1]);
break;
}
gopcode(OASHL, nodconst(v), l, r);
break;
}
p += 2;
goto loop;
}
void
sextern(Sym *s, Node *a, long o, long w)
{
long e, lw;
for(e=0; e<w; e+=NSNAME) {
lw = NSNAME;
if(w-e < lw)
lw = w-e;
gpseudo(ADATA, s, nodconst(0));
p->from.offset += o+e;
p->reg = lw;
p->to.type = D_SCONST;
memmove(p->to.sval, a->cstring+e, lw);
}
}
void
gextern(Sym *s, Node *a, long o, long w)
{
if(a->op == OCONST && typev[a->type->etype]) {
if(align(0, types[TCHAR], Aarg1)) /* isbigendian */
gpseudo(ADATA, s, nod32const(a->vconst>>32));
else
gpseudo(ADATA, s, nod32const(a->vconst));
p->from.offset += o;
p->reg = 4;
if(align(0, types[TCHAR], Aarg1)) /* isbigendian */
gpseudo(ADATA, s, nod32const(a->vconst));
else
gpseudo(ADATA, s, nod32const(a->vconst>>32));
p->from.offset += o + 4;
p->reg = 4;
return;
}
gpseudo(ADATA, s, a);
p->from.offset += o;
p->reg = w;
if(p->to.type == D_OREG)
p->to.type = D_CONST;
}
void zname(Biobuf*, Sym*, int);
char* zaddr(char*, Adr*, int);
void zwrite(Biobuf*, Prog*, int, int);
void outhist(Biobuf*);
void
zwrite(Biobuf *b, Prog *p, int sf, int st)
{
char bf[100], *bp;
bf[0] = p->as;
bf[1] = p->scond;
bf[2] = p->reg;
bf[3] = p->lineno;
bf[4] = p->lineno>>8;
bf[5] = p->lineno>>16;
bf[6] = p->lineno>>24;
bp = zaddr(bf+7, &p->from, sf);
bp = zaddr(bp, &p->to, st);
Bwrite(b, bf, bp-bf);
}
void
outcode(void)
{
struct { Sym *sym; short type; } h[NSYM];
Prog *p;
Sym *s;
int sf, st, t, sym;
if(debug['S']) {
for(p = firstp; p != P; p = p->link)
if(p->as != ADATA && p->as != AGLOBL)
pc--;
for(p = firstp; p != P; p = p->link) {
print("%P\n", p);
if(p->as != ADATA && p->as != AGLOBL)
pc++;
}
}
outhist(&outbuf);
for(sym=0; sym<NSYM; sym++) {
h[sym].sym = S;
h[sym].type = 0;
}
sym = 1;
for(p = firstp; p != P; p = p->link) {
jackpot:
sf = 0;
s = p->from.sym;
while(s != S) {
sf = s->sym;
if(sf < 0 || sf >= NSYM)
sf = 0;
t = p->from.name;
if(h[sf].type == t)
if(h[sf].sym == s)
break;
s->sym = sym;
zname(&outbuf, s, t);
h[sym].sym = s;
h[sym].type = t;
sf = sym;
sym++;
if(sym >= NSYM)
sym = 1;
break;
}
st = 0;
s = p->to.sym;
while(s != S) {
st = s->sym;
if(st < 0 || st >= NSYM)
st = 0;
t = p->to.name;
if(h[st].type == t)
if(h[st].sym == s)
break;
s->sym = sym;
zname(&outbuf, s, t);
h[sym].sym = s;
h[sym].type = t;
st = sym;
sym++;
if(sym >= NSYM)
sym = 1;
if(st == sf)
goto jackpot;
break;
}
zwrite(&outbuf, p, sf, st);
}
firstp = P;
lastp = P;
}
void
outhist(Biobuf *b)
{
Hist *h;
char *p, *q, *op, c;
Prog pg;
int n;
pg = zprog;
pg.as = AHISTORY;
c = pathchar();
for(h = hist; h != H; h = h->link) {
p = h->name;
op = 0;
/* on windows skip drive specifier in pathname */
if(systemtype(Windows) && p && p[1] == ':'){
p += 2;
c = *p;
}
if(p && p[0] != c && h->offset == 0 && pathname){
/* on windows skip drive specifier in pathname */
if(systemtype(Windows) && pathname[1] == ':') {
op = p;
p = pathname+2;
c = *p;
} else if(pathname[0] == c){
op = p;
p = pathname;
}
}
while(p) {
q = utfrune(p, c);
if(q) {
n = q-p;
if(n == 0){
n = 1; /* leading "/" */
*p = '/'; /* don't emit "\" on windows */
}
q++;
} else {
n = strlen(p);
q = 0;
}
if(n) {
Bputc(b, ANAME);
Bputc(b, D_FILE);
Bputc(b, 1);
Bputc(b, '<');
Bwrite(b, p, n);
Bputc(b, 0);
}
p = q;
if(p == 0 && op) {
p = op;
op = 0;
}
}
pg.lineno = h->line;
pg.to.type = zprog.to.type;
pg.to.offset = h->offset;
if(h->offset)
pg.to.type = D_CONST;
zwrite(b, &pg, 0, 0);
}
}
void
zname(Biobuf *b, Sym *s, int t)
{
char *n, bf[7];
ulong sig;
n = s->name;
if(debug['T'] && t == D_EXTERN && s->sig != SIGDONE && s->type != types[TENUM] && s != symrathole){
sig = sign(s);
bf[0] = ASIGNAME;
bf[1] = sig;
bf[2] = sig>>8;
bf[3] = sig>>16;
bf[4] = sig>>24;
bf[5] = t;
bf[6] = s->sym;
Bwrite(b, bf, 7);
s->sig = SIGDONE;
}
else{
bf[0] = ANAME;
bf[1] = t; /* type */
bf[2] = s->sym; /* sym */
Bwrite(b, bf, 3);
}
Bwrite(b, n, strlen(n)+1);
}
char*
zaddr(char *bp, Adr *a, int s)
{
long l;
Ieee e;
bp[0] = a->type;
bp[1] = a->reg;
bp[2] = s;
bp[3] = a->name;
bp += 4;
switch(a->type) {
default:
diag(Z, "unknown type %d in zaddr", a->type);
case D_NONE:
case D_REG:
case D_FREG:
case D_PSR:
break;
case D_REGREG:
*bp++ = a->offset;
break;
case D_OREG:
case D_CONST:
case D_BRANCH:
case D_SHIFT:
l = a->offset;
bp[0] = l;
bp[1] = l>>8;
bp[2] = l>>16;
bp[3] = l>>24;
bp += 4;
break;
case D_SCONST:
memmove(bp, a->sval, NSNAME);
bp += NSNAME;
break;
case D_FCONST:
ieeedtod(&e, a->dval);
l = e.l;
bp[0] = l;
bp[1] = l>>8;
bp[2] = l>>16;
bp[3] = l>>24;
bp += 4;
l = e.h;
bp[0] = l;
bp[1] = l>>8;
bp[2] = l>>16;
bp[3] = l>>24;
bp += 4;
break;
}
return bp;
}
long
align(long i, Type *t, int op)
{
long o;
Type *v;
int w;
o = i;
w = 1;
switch(op) {
default:
diag(Z, "unknown align opcode %d", op);
break;
case Asu2: /* padding at end of a struct */
w = SZ_LONG;
if(packflg)
w = packflg;
break;
case Ael1: /* initial align of struct element */
for(v=t; v->etype==TARRAY; v=v->link)
;
w = ewidth[v->etype];
if(w <= 0 || w >= SZ_LONG)
w = SZ_LONG;
if(packflg)
w = packflg;
break;
case Ael2: /* width of a struct element */
o += t->width;
break;
case Aarg0: /* initial passbyptr argument in arg list */
if(typesuv[t->etype]) {
o = align(o, types[TIND], Aarg1);
o = align(o, types[TIND], Aarg2);
}
break;
case Aarg1: /* initial align of parameter */
w = ewidth[t->etype];
if(w <= 0 || w >= SZ_LONG) {
w = SZ_LONG;
break;
}
w = 1; /* little endian no adjustment */
break;
case Aarg2: /* width of a parameter */
o += t->width;
w = SZ_LONG;
break;
case Aaut3: /* total align of automatic */
o = align(o, t, Ael2);
o = align(o, t, Ael1);
w = SZ_LONG; /* because of a pun in cc/dcl.c:contig() */
break;
}
o = round(o, w);
if(debug['A'])
print("align %s %ld %T = %ld\n", bnames[op], i, t, o);
return o;
}
long
maxround(long max, long v)
{
v = round(v, SZ_LONG);
if(v > max)
return v;
return max;
}