void
swit2(C1 *q, int nc, int32 def, Node *n)
{
C1 *r;
int i;
Prog *sp;
if(nc < 5) {
for(i=0; i<nc; i++) {
if(debug['W'])
print("case = %.8ux\n", q->val);
gopcode(OEQ, n->type, n, nodconst(q->val));
patch(p, q->label);
q++;
}
gbranch(OGOTO);
patch(p, def);
return;
}
i = nc / 2;
r = q+i;
if(debug['W'])
print("case > %.8ux\n", r->val);
gopcode(OGT, n->type, n, nodconst(r->val));
sp = p;
gbranch(OGOTO);
p->as = AJEQ;
patch(p, r->label);
swit2(q, i, def, n);
if(debug['W'])
print("case < %.8ux\n", r->val);
patch(sp, pc);
swit2(r+1, nc-i-1, def, n);
}
void
swit1(C1 *q, int nc, int32_t def, Node *n)
{
C1 *r;
int i;
Prog *sp;
if(nc < 5) {
for(i=0; i<nc; i++) {
if(debug['K'])
print("case = %.8llux\n", q->val);
gcmp(OEQ, n, q->val);
patch(p, q->label);
q++;
}
gbranch(OGOTO);
patch(p, def);
return;
}
i = nc / 2;
r = q+i;
if(debug['K'])
print("case > %.8llux\n", r->val);
gcmp(OGT, n, r->val);
sp = p;
gbranch(OGOTO);
p->as = AJEQ;
patch(p, r->label);
swit1(q, i, def, n);
if(debug['K'])
print("case < %.8llux\n", r->val);
patch(sp, pc);
swit1(r+1, nc-i-1, def, n);
}
/* else binary */
void
swit1(C1 *q, int nc, long def, int g, Node *n)
{
C1 *r;
int i;
long v;
Prog *sp1, *sp2;
/* note that g and g+1 are not allocated */
if(nc <= N1)
goto linear;
/*
* divide and conquer
*/
i = nc / 2;
r = q+i;
v = r->val;
/* compare median */
if(v >= -128 && v < 128) {
gopcode(OAS, n->type, D_CONST, nodconst(v), g+1, n);
gopcode(OEQ, n->type, g, n, g+1, n);
} else
gopcode(OEQ, n->type, g, n, D_CONST, nodconst(v));
gbranch(OLT);
sp1 = p;
gbranch(OGT);
sp2 = p;
gbranch(OGOTO);
patch(p, r->label);
patch(sp1, pc);
swit1(q, i, def, g, n);
patch(sp2, pc);
swit1(r+1, nc-i-1, def, g, n);
return;
linear:
for(i=0; i<nc; i++) {
v = q->val;
if(v >= -128 && v < 128) {
gopcode(OAS, n->type, D_CONST, nodconst(v), g+1, n);
gopcode(OEQ, n->type, g+1, n, g, n);
} else
gopcode(OEQ, n->type, g, n, D_CONST, nodconst(v));
gbranch(OEQ);
patch(p, q->label);
q++;
}
gbranch(OGOTO);
patch(p, def);
}
void galign(int n, int v) {
int b;
b = gbranch(CodeAlign);
branch[b].param = n;
branch[b].target = v;
}
void
codgen(Node *n, Node *nn)
{
Prog *sp;
argoff = 0;
inargs = 0;
for(;; nn = nn->left) {
if(nn == Z) {
diag(Z, "cant find function name");
return;
}
if(nn->op == ONAME)
break;
}
nearln = nn->lineno;
gpseudo(ATEXT, nn->sym, D_CONST, stkoff);
sp = p;
retok = 0;
gen(n);
if(!retok)
if(thisfn->link->etype != TVOID)
warn(Z, "no return at end of function: %s", nn->sym->name);
noretval(3);
gbranch(ORETURN);
if(!debug['N'] || debug['R'] || debug['P'])
regopt(sp);
}
int
bcomplex(Node *n, Node *c)
{
Node *b, nod;
complex(n);
if(n->type != T)
if(tcompat(n, T, n->type, tnot))
n->type = T;
if(n->type == T) {
gbranch(OGOTO);
return 0;
}
if(c != Z && n->op == OCONST && deadheads(c))
return 1;
if(typev[n->type->etype] && machcap(Z)) {
b = &nod;
b->op = ONE;
b->left = n;
b->right = new(0, Z, Z);
*b->right = *nodconst(0);
b->right->type = n->type;
b->type = types[TLONG];
n = b;
}
void
swit1(C1 *q, int nc, long def, Node *n)
{
C1 *r;
int i;
Prog *sp;
if(nc < 5) {
for(i=0; i<nc; i++) {
if(debug['W'])
print("case = %.8lux\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 > %.8lux\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);
swit1(q, i, def, n);
if(debug['W'])
print("case < %.8lux\n", r->val);
patch(sp, pc);
swit1(r+1, nc-i-1, def, n);
}
void
codgen(Node *n, Node *nn)
{
Prog *sp;
Node *n1, nod, nod1;
cursafe = 0;
curarg = 0;
maxargsafe = 0;
/*
* isolate name
*/
for(n1 = nn;; n1 = n1->left) {
if(n1 == Z) {
diag(nn, "cant find function name");
return;
}
if(n1->op == ONAME)
break;
}
nearln = nn->lineno;
gpseudo(ATEXT, n1->sym, nodconst(stkoff));
sp = p;
sp->reg |= ALLTHUMBS; /* denotes thumb code */
/*
* isolate first argument
*/
if(REGARG >= 0) {
if(typesuv[thisfn->link->etype]) {
nod1 = *nodret->left;
nodreg(&nod, &nod1, REGARG);
gopcode(OAS, &nod, Z, &nod1);
} else
if(firstarg && typechlp[firstargtype->etype]) {
nod1 = *nodret->left;
nod1.sym = firstarg;
nod1.type = firstargtype;
nod1.xoffset = align(0, firstargtype, Aarg1);
nod1.etype = firstargtype->etype;
nodreg(&nod, &nod1, REGARG);
gopcode(OAS, &nod, Z, &nod1);
}
}
retok = 0;
gen(n);
if(!retok)
if(thisfn->link->etype != TVOID)
warn(Z, "no return at end of function: %s", n1->sym->name);
noretval(3);
gbranch(ORETURN);
if(!debug['N'] || debug['R'] || debug['P'])
regopt(sp);
sp->to.offset += maxargsafe;
}
int gjmp(int l, int c) {
int b;
b = gbranch(CodeJump);
branch[b].target = l;
branch[b].param = c;
return b;
}
// Output relocation
void greloc(Sym *sym, int c, int rel) {
int b;
if (sym && !sym->c) put_extern_sym(sym, NULL, 0, 0);
b = gbranch(CodeReloc);
if (sym) branch[b].target = sym->c;
branch[b].param = rel;
gen_le32(c);
}
// Generate function epilog
void gfunc_epilog(void) {
// Mark end of code
gbranch(CodeEnd);
// Output code for function
gcode();
// Clear code buffer
clear_code_buf();
}
void
swit2(C1 *q, int nc, long def, Node *n, Node *tn)
{
C1 *r;
int i;
Prog *sp;
if(nc < 5) {
for(i=0; i<nc; i++) {
if(sval(q->val)) {
gopcode(OEQ, n, Z, nodconst(q->val));
} else {
gopcode(OSUB, nodconst(q->val), n, tn);
gopcode(OEQ, tn, Z, nodconst(0));
}
patch(p, q->label);
q++;
}
gbranch(OGOTO);
patch(p, def);
return;
}
i = nc / 2;
r = q+i;
if(sval(r->val)) {
gopcode(OGT, n, Z, nodconst(r->val));
sp = p;
} else {
gopcode(OSUB, nodconst(r->val), n, tn);
gopcode(OGT, tn, Z, nodconst(0));
sp = p;
}
gbranch(OGOTO);
p->as = ABEQ;
patch(p, r->label);
swit2(q, i, def, n, tn);
patch(sp, pc);
swit2(r+1, nc-i-1, def, n, tn);
}
void
lcgen(Node *n, Node *nn)
{
Prog *p1;
Node nod;
if(debug['g']) {
prtree(nn, "lcgen lhs");
prtree(n, "lcgen");
}
if(n == Z || n->type == T)
return;
if(nn == Z) {
nn = &nod;
regalloc(&nod, n, Z);
}
switch(n->op) {
default:
if(n->addable < INDEXED) {
diag(n, "unknown op in lcgen: %O", n->op);
break;
}
nod = *n;
nod.op = OADDR;
nod.left = n;
nod.right = Z;
nod.type = types[TIND];
gopcode(OAS, &nod, Z, nn);
break;
case OCOMMA:
cgen(n->left, n->left);
lcgen(n->right, nn);
break;
case OIND:
cgen(n->left, nn);
break;
case OCOND:
bcgen(n->left, 1);
p1 = p;
lcgen(n->right->left, nn);
gbranch(OGOTO);
patch(p1, pc);
p1 = p;
lcgen(n->right->right, nn);
patch(p1, pc);
break;
}
}
void
bcomplex(Node *n)
{
complex(n);
if(n->type != T)
if(tcompat(n, T, n->type, tnot))
n->type = T;
if(n->type != T) {
bool64(n);
doinc(n, PRE);
boolgen(n, 1, D_NONE, Z, n);
} else
gbranch(OGOTO);
}
void paste_code_buffer(CodeBuffer *cb) {
int i;
int ind_ofs = ind;
int br_ofs = br;
for (i = 0; i < cb->ind; ++i) g(cb->code[i]);
for (i = 0; i < cb->br; ++i) {
Branch *b = branch + gbranch(cb->branch[i].type);
*b = cb->branch[i];
b->ind += ind_ofs;
if (b->type == CodeJump) b->target += br_ofs;
}
free(cb->code);
free(cb->branch);
}
int
bcomplex(Node *n, Node *c)
{
complex(n);
if(n->type != T)
if(tcompat(n, T, n->type, tnot))
n->type = T;
if(n->type != T) {
if(c != Z && n->op == OCONST && deadheads(c))
return 1;
bool64(n);
boolgen(n, 1, Z);
} else
gbranch(OGOTO);
return 0;
}
void
codgen(Node *n, Node *nn)
{
Prog *sp;
Node *n1, nod, nod1;
cursafe = 0;
curarg = 0;
maxargsafe = 0;
/*
* isolate name
*/
for(n1 = nn;; n1 = n1->left) {
if(n1 == Z) {
diag(nn, "cant find function name");
return;
}
if(n1->op == ONAME)
break;
}
nearln = nn->lineno;
p = gtext(n1->sym, stkoff);
sp = p;
/*
* isolate first argument
*/
if(REGARG >= 0) {
if(typesuv[thisfn->link->etype]) {
nod1 = *nodret->left;
nodreg(&nod, &nod1, REGARG);
gmove(&nod, &nod1);
} else
if(firstarg && typechlp[firstargtype->etype]) {
nod1 = *nodret->left;
nod1.sym = firstarg;
nod1.type = firstargtype;
nod1.xoffset = align(0, firstargtype, Aarg1, nil);
nod1.etype = firstargtype->etype;
nodreg(&nod, &nod1, REGARG);
gmove(&nod, &nod1);
}
}
retok = 0;
canreach = 1;
warnreach = 1;
gen(n);
if(canreach && thisfn->link->etype != TVOID)
diag(Z, "no return at end of function: %s", n1->sym->name);
noretval(3);
gbranch(ORETURN);
if(!debug['N'] || debug['R'] || debug['P'])
regopt(sp);
if(thechar=='6' || thechar=='7') /* [sic] */
maxargsafe = xround(maxargsafe, 8);
sp->to.offset += maxargsafe;
}
void
doswit(Node *n)
{
Case *c;
C1 *q, *iq, *iqh, *iql;
long def, nc, i, j, isv, nh;
Prog *hsb;
Node *vr[2];
int dup;
def = 0;
nc = 0;
isv = 0;
for(c = cases; c->link != C; c = c->link) {
if(c->def) {
if(def)
diag(n, "more than one default in switch");
def = c->label;
continue;
}
isv |= c->isv;
nc++;
}
if(typev[n->type->etype])
isv = 1;
else if(isv){
warn(n, "32-bit switch expression with 64-bit case constant");
isv = 0;
}
iq = alloc(nc*sizeof(C1));
q = iq;
for(c = cases; c->link != C; c = c->link) {
if(c->def)
continue;
if(c->isv && !isv)
continue; /* can never match */
q->label = c->label;
if(isv)
q->val = c->val;
else
q->val = (long)c->val; /* cast ensures correct value for 32-bit switch on 64-bit architecture */
q++;
}
qsort(iq, nc, sizeof(C1), swcmp);
if(debug['K'])
for(i=0; i<nc; i++)
print("case %2ld: = %.8llux\n", i, (vlong)iq[i].val);
dup = 0;
for(i=0; i<nc-1; i++)
if(iq[i].val == iq[i+1].val) {
diag(n, "duplicate cases in switch %lld", (vlong)iq[i].val);
dup = 1;
}
if(dup)
return;
if(def == 0) {
def = breakpc;
nbreak++;
}
if(!isv || ewidth[TIND] > ewidth[TLONG] || n->op == OREGISTER) {
swit1(iq, nc, def, n);
return;
}
/*
* 64-bit case on 32-bit machine:
* switch on high-order words, and
* in each of those, switch on low-order words
*/
if(n->op != OREGPAIR)
fatal(n, "internal: expected register pair");
if(thechar == '8'){ /* TO DO: need an enquiry function */
vr[0] = n->left; /* low */
vr[1] = n->right; /* high */
}else{
vr[0] = n->right;
vr[1] = n->left;
}
vr[0]->type = types[TLONG];
vr[1]->type = types[TLONG];
gbranch(OGOTO);
hsb = p;
iqh = alloc(nc*sizeof(C1));
iql = alloc(nc*sizeof(C1));
nh = 0;
for(i=0; i<nc;){
iqh[nh].val = iq[i].val >> 32;
q = iql;
/* iq is sorted, so equal top halves are adjacent */
for(j = i; j < nc; j++){
if((iq[j].val>>32) != iqh[nh].val)
break;
q->val = (long)iq[j].val;
q->label = iq[j].label;
q++;
}
qsort(iql, q-iql, sizeof(C1), swcmp);
if(0){for(int k=0; k<(q-iql); k++)print("nh=%ld k=%d h=%#llux l=%#llux lab=%ld\n", nh, k, (vlong)iqh[nh].val, (vlong)iql[k].val, iql[k].label);}
iqh[nh].label = pc;
nh++;
swit1(iql, q-iql, def, vr[0]);
i = j;
}
patch(hsb, pc);
if(0){for(int k=0; k<nh; k++)print("k*=%d h=%#llux lab=%ld\n", k, (vlong)iqh[k].val, iqh[k].label);}
swit1(iqh, nh, def, vr[1]);
}
void
gen(Node *n)
{
Node *l, nod;
Prog *sp, *spc, *spb;
Case *cn;
long sbc, scc;
int snbreak, sncontin;
int f, o, oldreach;
loop:
if(n == Z)
return;
nearln = n->lineno;
o = n->op;
if(debug['G'])
if(o != OLIST)
print("%L %O\n", nearln, o);
if(!canreach) {
switch(o) {
case OLABEL:
case OCASE:
case OLIST:
case OBREAK:
case OFOR:
case OWHILE:
case ODWHILE:
/* all handled specially - see switch body below */
break;
default:
if(warnreach) {
warn(n, "unreachable code %O", o);
warnreach = 0;
}
}
}
switch(o) {
default:
complex(n);
cgen(n, Z);
break;
case OLIST:
gen(n->left);
rloop:
n = n->right;
goto loop;
case ORETURN:
canreach = 0;
warnreach = !suppress;
complex(n);
if(n->type == T)
break;
l = n->left;
if(l == Z) {
noretval(3);
gbranch(ORETURN);
break;
}
if(typecmplx[n->type->etype]) {
sugen(l, nodret, n->type->width);
noretval(3);
gbranch(ORETURN);
break;
}
regret(&nod, n);
cgen(l, &nod);
regfree(&nod);
if(typefd[n->type->etype])
noretval(1);
else
noretval(2);
gbranch(ORETURN);
break;
case OLABEL:
canreach = 1;
l = n->left;
if(l) {
l->pc = pc;
if(l->label)
patch(l->label, pc);
}
gbranch(OGOTO); /* prevent self reference in reg */
patch(p, pc);
goto rloop;
case OGOTO:
canreach = 0;
warnreach = !suppress;
n = n->left;
if(n == Z)
return;
if(n->complex == 0) {
diag(Z, "label undefined: %s", n->sym->name);
return;
}
if(suppress)
return;
gbranch(OGOTO);
if(n->pc) {
patch(p, n->pc);
return;
}
if(n->label)
patch(n->label, pc-1);
n->label = p;
return;
case OCASE:
canreach = 1;
l = n->left;
if(cases == C)
diag(n, "case/default outside a switch");
if(l == Z) {
newcase();
cases->val = 0;
cases->def = 1;
cases->label = pc;
cases->isv = 0;
goto rloop;
}
complex(l);
if(l->type == T)
goto rloop;
if(l->op == OCONST)
if(typeword[l->type->etype] && l->type->etype != TIND) {
newcase();
cases->val = l->vconst;
cases->def = 0;
cases->label = pc;
cases->isv = typev[l->type->etype];
goto rloop;
}
diag(n, "case expression must be integer constant");
goto rloop;
case OSWITCH:
l = n->left;
complex(l);
if(l->type == T)
break;
if(!typechlvp[l->type->etype] || l->type->etype == TIND) {
diag(n, "switch expression must be integer");
break;
}
gbranch(OGOTO); /* entry */
sp = p;
cn = cases;
cases = C;
newcase();
sbc = breakpc;
breakpc = pc;
snbreak = nbreak;
nbreak = 0;
gbranch(OGOTO);
spb = p;
gen(n->right); /* body */
if(canreach){
gbranch(OGOTO);
patch(p, breakpc);
nbreak++;
}
patch(sp, pc);
doswit(l);
patch(spb, pc);
cases = cn;
breakpc = sbc;
canreach = nbreak!=0;
if(canreach == 0)
warnreach = !suppress;
nbreak = snbreak;
break;
case OWHILE:
case ODWHILE:
l = n->left;
gbranch(OGOTO); /* entry */
sp = p;
scc = continpc;
continpc = pc;
gbranch(OGOTO);
spc = p;
sbc = breakpc;
breakpc = pc;
snbreak = nbreak;
nbreak = 0;
gbranch(OGOTO);
spb = p;
patch(spc, pc);
if(n->op == OWHILE)
patch(sp, pc);
bcomplex(l, Z); /* test */
patch(p, breakpc);
if(l->op != OCONST || vconst(l) == 0)
nbreak++;
if(n->op == ODWHILE)
patch(sp, pc);
gen(n->right); /* body */
gbranch(OGOTO);
patch(p, continpc);
patch(spb, pc);
continpc = scc;
breakpc = sbc;
canreach = nbreak!=0;
if(canreach == 0)
warnreach = !suppress;
nbreak = snbreak;
break;
case OFOR:
l = n->left;
if(!canreach && l->right->left && warnreach) {
warn(n, "unreachable code FOR");
warnreach = 0;
}
gen(l->right->left); /* init */
gbranch(OGOTO); /* entry */
sp = p;
/*
* if there are no incoming labels in the
* body and the top's not reachable, warn
*/
if(!canreach && warnreach && deadheads(n)) {
warn(n, "unreachable code %O", o);
warnreach = 0;
}
scc = continpc;
continpc = pc;
gbranch(OGOTO);
spc = p;
sbc = breakpc;
breakpc = pc;
snbreak = nbreak;
nbreak = 0;
sncontin = ncontin;
ncontin = 0;
gbranch(OGOTO);
spb = p;
patch(spc, pc);
gen(l->right->right); /* inc */
patch(sp, pc);
if(l->left != Z) { /* test */
bcomplex(l->left, Z);
patch(p, breakpc);
if(l->left->op != OCONST || vconst(l->left) == 0)
nbreak++;
}
canreach = 1;
gen(n->right); /* body */
if(canreach){
gbranch(OGOTO);
patch(p, continpc);
ncontin++;
}
if(!ncontin && l->right->right && warnreach) {
warn(l->right->right, "unreachable FOR inc");
warnreach = 0;
}
patch(spb, pc);
continpc = scc;
breakpc = sbc;
canreach = nbreak!=0;
if(canreach == 0)
warnreach = !suppress;
nbreak = snbreak;
ncontin = sncontin;
break;
case OCONTINUE:
if(continpc < 0) {
diag(n, "continue not in a loop");
break;
}
gbranch(OGOTO);
patch(p, continpc);
ncontin++;
canreach = 0;
warnreach = !suppress;
break;
case OBREAK:
if(breakpc < 0) {
diag(n, "break not in a loop");
break;
}
/*
* Don't complain about unreachable break statements.
* There are breaks hidden in yacc's output and some people
* write return; break; in their switch statements out of habit.
* However, don't confuse the analysis by inserting an
* unreachable reference to breakpc either.
*/
if(!canreach)
break;
gbranch(OGOTO);
patch(p, breakpc);
nbreak++;
canreach = 0;
warnreach = !suppress;
break;
case OIF:
l = n->left;
if(bcomplex(l, n->right)) {
if(typefd[l->type->etype])
f = !l->fconst;
else
f = !l->vconst;
if(debug['c'])
print("%L const if %s\n", nearln, f ? "false" : "true");
if(f) {
canreach = 1;
supgen(n->right->left);
oldreach = canreach;
canreach = 1;
gen(n->right->right);
/*
* treat constant ifs as regular ifs for
* reachability warnings.
*/
if(!canreach && oldreach && debug['w'] < 2)
warnreach = 0;
}
else {
canreach = 1;
gen(n->right->left);
oldreach = canreach;
canreach = 1;
supgen(n->right->right);
/*
* treat constant ifs as regular ifs for
* reachability warnings.
*/
if(!oldreach && canreach && debug['w'] < 2)
warnreach = 0;
canreach = oldreach;
}
}
else {
sp = p;
canreach = 1;
if(n->right->left != Z)
gen(n->right->left);
oldreach = canreach;
canreach = 1;
if(n->right->right != Z) {
gbranch(OGOTO);
patch(sp, pc);
sp = p;
gen(n->right->right);
}
patch(sp, pc);
canreach = canreach || oldreach;
if(canreach == 0)
warnreach = !suppress;
}
break;
case OSET:
case OUSED:
case OPREFETCH:
usedset(n->left, o);
break;
}
}
void
gen(Node *n)
{
Node *l;
Prog *sp, *spc, *spb;
Case *cn;
long sbc, scc;
int snbreak;
int g, o;
loop:
if(n == Z)
return;
nearln = n->lineno;
o = n->op;
if(debug['G'])
if(o != OLIST)
print("%L %O\n", nearln, o);
retok = 0;
switch(o) {
default:
complex(n);
doinc(n, PRE);
cgen(n, D_NONE, n);
doinc(n, POST);
break;
case OLIST:
gen(n->left);
rloop:
n = n->right;
goto loop;
case ORETURN:
retok = 1;
complex(n);
if(n->type == T)
break;
l = n->left;
if(l == Z) {
noretval(3);
gbranch(ORETURN);
break;
}
doinc(l, PRE);
if(typesuv[n->type->etype]) {
sugen(l, D_TREE, nodret, n->type->width);
doinc(l, POST);
noretval(3);
gbranch(ORETURN);
break;
}
g = regalloc(n->type, regret(n->type));
cgen(l, g, n);
doinc(l, POST);
if(typefd[n->type->etype])
noretval(1);
else
noretval(2);
gbranch(ORETURN);
regfree(g);
break;
case OLABEL:
l = n->left;
if(l) {
l->xoffset = pc;
if(l->label)
patch(l->label, pc);
}
gbranch(OGOTO); /* prevent self reference in reg */
patch(p, pc);
goto rloop;
case OGOTO:
retok = 1;
n = n->left;
if(n == Z)
return;
if(n->complex == 0) {
diag(Z, "label undefined: %s", n->sym->name);
return;
}
gbranch(OGOTO);
if(n->xoffset) {
patch(p, n->xoffset);
return;
}
if(n->label)
patch(n->label, pc-1);
n->label = p;
return;
case OCASE:
l = n->left;
if(cases == C)
diag(n, "case/default outside a switch");
if(l == Z) {
casf();
cases->val = 0;
cases->def = 1;
cases->label = pc;
setsp();;
goto rloop;
}
complex(l);
if(l->type == T)
goto rloop;
if(l->op == OCONST)
if(typechl[l->type->etype]) {
casf();
cases->val = l->vconst;
cases->def = 0;
cases->label = pc;
setsp();
goto rloop;
}
diag(n, "case expression must be integer constant");
goto rloop;
case OSWITCH:
l = n->left;
complex(l);
doinc(l, PRE);
if(l->type == T)
break;
if(!typechl[l->type->etype]) {
diag(n, "switch expression must be integer");
break;
}
g = regalloc(types[TLONG], D_NONE);
n->type = types[TLONG];
cgen(l, g, n);
regfree(g);
doinc(l, POST);
setsp();
gbranch(OGOTO); /* entry */
sp = p;
cn = cases;
cases = C;
casf();
sbc = breakpc;
breakpc = pc;
snbreak = nbreak;
nbreak = 0;
gbranch(OGOTO);
spb = p;
gen(n->right);
gbranch(OGOTO);
patch(p, breakpc);
nbreak++;
patch(sp, pc);
doswit(g, l);
patch(spb, pc);
cases = cn;
breakpc = sbc;
nbreak = snbreak;
setsp();
break;
case OWHILE:
case ODWHILE:
l = n->left;
gbranch(OGOTO); /* entry */
sp = p;
scc = continpc;
continpc = pc;
gbranch(OGOTO);
spc = p;
sbc = breakpc;
breakpc = pc;
snbreak = nbreak;
nbreak = 0;
gbranch(OGOTO);
spb = p;
patch(spc, pc);
if(n->op == OWHILE)
patch(sp, pc);
bcomplex(l); /* test */
patch(p, breakpc);
if(l->op != OCONST || vconst(l) == 0)
nbreak++;
if(n->op == ODWHILE)
patch(sp, pc);
gen(n->right); /* body */
gbranch(OGOTO);
patch(p, continpc);
patch(spb, pc);
continpc = scc;
breakpc = sbc;
if(nbreak == 0)
retok = 1;
nbreak = snbreak;
break;
case OFOR:
l = n->left;
gen(l->right->left); /* init */
gbranch(OGOTO); /* entry */
sp = p;
scc = continpc;
continpc = pc;
gbranch(OGOTO);
spc = p;
sbc = breakpc;
breakpc = pc;
snbreak = nbreak;
nbreak = 0;
gbranch(OGOTO);
spb = p;
patch(spc, pc);
gen(l->right->right); /* inc */
patch(sp, pc);
if(l->left != Z) { /* test */
bcomplex(l->left);
patch(p, breakpc);
if(l->left->op != OCONST || vconst(l->left) == 0)
nbreak++;
}
gen(n->right); /* body */
gbranch(OGOTO);
patch(p, continpc);
patch(spb, pc);
continpc = scc;
breakpc = sbc;
if(nbreak == 0)
retok = 1;
nbreak = snbreak;
break;
case OCONTINUE:
if(continpc < 0) {
diag(n, "continue not in a loop");
break;
}
gbranch(OGOTO);
patch(p, continpc);
break;
case OBREAK:
if(breakpc < 0) {
diag(n, "break not in a loop");
break;
}
gbranch(OGOTO);
patch(p, breakpc);
nbreak++;
break;
case OIF:
l = n->left;
bcomplex(l);
sp = p;
if(n->right->left != Z)
gen(n->right->left);
if(n->right->right != Z) {
gbranch(OGOTO);
patch(sp, pc);
sp = p;
gen(n->right->right);
}
patch(sp, pc);
break;
case OSET:
case OUSED:
usedset(n->left, o);
break;
}
}
void gline(int linenum) {
int b;
b = gbranch(CodeLine);
branch[b].target = linenum;
}
void
gen(Node *n)
{
Node *l, nod;
Prog *sp, *spc, *spb;
Case *cn;
long sbc, scc;
int o, f;
loop:
if(n == Z)
return;
nearln = n->lineno;
o = n->op;
if(debug['G'])
if(o != OLIST)
print("%L %O\n", nearln, o);
retok = 0;
switch(o) {
default:
complex(n);
cgen(n, Z);
break;
case OLIST:
gen(n->left);
rloop:
n = n->right;
goto loop;
case ORETURN:
retok = 1;
complex(n);
if(n->type == T)
break;
l = n->left;
if(l == Z) {
noretval(3);
gbranch(ORETURN);
break;
}
if(typesuv[n->type->etype]) {
sugen(l, nodret, n->type->width);
noretval(3);
gbranch(ORETURN);
break;
}
regret(&nod, n);
cgen(l, &nod);
regfree(&nod);
if(typefd[n->type->etype])
noretval(1);
else
noretval(2);
gbranch(ORETURN);
break;
case OLABEL:
l = n->left;
if(l) {
l->pc = pc;
if(l->label)
patch(l->label, pc);
}
gbranch(OGOTO); /* prevent self reference in reg */
patch(p, pc);
goto rloop;
case OGOTO:
retok = 1;
n = n->left;
if(n == Z)
return;
if(n->complex == 0) {
diag(Z, "label undefined: %s", n->sym->name);
return;
}
if(suppress)
return;
gbranch(OGOTO);
if(n->pc) {
patch(p, n->pc);
return;
}
if(n->label)
patch(n->label, pc-1);
n->label = p;
return;
case OCASE:
l = n->left;
if(cases == C)
diag(n, "case/default outside a switch");
if(l == Z) {
casf();
cases->val = 0;
cases->def = 1;
cases->label = pc;
goto rloop;
}
complex(l);
if(l->type == T)
goto rloop;
if(l->op == OCONST)
if(typechl[l->type->etype]) {
casf();
cases->val = l->vconst;
cases->def = 0;
cases->label = pc;
goto rloop;
}
diag(n, "case expression must be integer constant");
goto rloop;
case OSWITCH:
l = n->left;
complex(l);
if(l->type == T)
break;
if(!typechl[l->type->etype]) {
diag(n, "switch expression must be integer");
break;
}
gbranch(OGOTO); /* entry */
sp = p;
cn = cases;
cases = C;
casf();
sbc = breakpc;
breakpc = pc;
gbranch(OGOTO);
spb = p;
gen(n->right);
gbranch(OGOTO);
patch(p, breakpc);
patch(sp, pc);
regalloc(&nod, l, Z);
nod.type = types[TLONG];
cgen(l, &nod);
doswit(&nod);
regfree(&nod);
patch(spb, pc);
cases = cn;
breakpc = sbc;
break;
case OWHILE:
case ODWHILE:
l = n->left;
gbranch(OGOTO); /* entry */
sp = p;
scc = continpc;
continpc = pc;
gbranch(OGOTO);
spc = p;
sbc = breakpc;
breakpc = pc;
gbranch(OGOTO);
spb = p;
patch(spc, pc);
if(n->op == OWHILE)
patch(sp, pc);
bcomplex(l, Z); /* test */
patch(p, breakpc);
if(n->op == ODWHILE)
patch(sp, pc);
gen(n->right); /* body */
gbranch(OGOTO);
patch(p, continpc);
patch(spb, pc);
continpc = scc;
breakpc = sbc;
break;
case OFOR:
l = n->left;
gen(l->right->left); /* init */
gbranch(OGOTO); /* entry */
sp = p;
scc = continpc;
continpc = pc;
gbranch(OGOTO);
spc = p;
sbc = breakpc;
breakpc = pc;
gbranch(OGOTO);
spb = p;
patch(spc, pc);
gen(l->right->right); /* inc */
patch(sp, pc);
if(l->left != Z) { /* test */
bcomplex(l->left, Z);
patch(p, breakpc);
}
gen(n->right); /* body */
gbranch(OGOTO);
patch(p, continpc);
patch(spb, pc);
continpc = scc;
breakpc = sbc;
break;
case OCONTINUE:
if(continpc < 0) {
diag(n, "continue not in a loop");
break;
}
gbranch(OGOTO);
patch(p, continpc);
break;
case OBREAK:
if(breakpc < 0) {
diag(n, "break not in a loop");
break;
}
gbranch(OGOTO);
patch(p, breakpc);
break;
case OIF:
l = n->left;
if(bcomplex(l, n->right)) {
if(typefd[l->type->etype])
f = !l->fconst;
else
f = !l->vconst;
if(debug['c'])
print("%L const if %s\n", nearln, f ? "false" : "true");
if(f) {
supgen(n->right->left);
gen(n->right->right);
}
else {
gen(n->right->left);
supgen(n->right->right);
}
}
else {
sp = p;
if(n->right->left != Z)
gen(n->right->left);
if(n->right->right != Z) {
gbranch(OGOTO);
patch(sp, pc);
sp = p;
gen(n->right->right);
}
patch(sp, pc);
}
break;
case OSET:
case OUSED:
usedset(n->left, o);
break;
}
}
void
cgen(Node *n, Node *nn)
{
Node *l, *r, *t;
Prog *p1;
Node nod, nod1, nod2, nod3, nod4;
int o, hardleft;
int32 v, curs;
vlong c;
if(debug['g']) {
prtree(nn, "cgen lhs");
prtree(n, "cgen");
}
if(n == Z || n->type == T)
return;
if(typesu[n->type->etype]) {
sugen(n, nn, n->type->width);
return;
}
l = n->left;
r = n->right;
o = n->op;
if(n->op == OEXREG || (nn != Z && nn->op == OEXREG)) {
gmove(n, nn);
return;
}
if(n->addable >= INDEXED) {
if(nn == Z) {
switch(o) {
default:
nullwarn(Z, Z);
break;
case OINDEX:
nullwarn(l, r);
break;
}
return;
}
gmove(n, nn);
return;
}
curs = cursafe;
if(l->complex >= FNX)
if(r != Z && r->complex >= FNX)
switch(o) {
default:
if(cond(o) && typesu[l->type->etype])
break;
regret(&nod, r);
cgen(r, &nod);
regsalloc(&nod1, r);
gmove(&nod, &nod1);
regfree(&nod);
nod = *n;
nod.right = &nod1;
cgen(&nod, nn);
return;
case OFUNC:
case OCOMMA:
case OANDAND:
case OOROR:
case OCOND:
case ODOT:
break;
}
hardleft = l->addable < INDEXED || l->complex >= FNX;
switch(o) {
default:
diag(n, "unknown op in cgen: %O", o);
break;
case ONEG:
case OCOM:
if(nn == Z) {
nullwarn(l, Z);
break;
}
regalloc(&nod, l, nn);
cgen(l, &nod);
gopcode(o, n->type, Z, &nod);
gmove(&nod, nn);
regfree(&nod);
break;
case OAS:
if(l->op == OBIT)
goto bitas;
if(!hardleft) {
if(nn != Z || r->addable < INDEXED || hardconst(r)) {
if(r->complex >= FNX && nn == Z)
regret(&nod, r);
else
regalloc(&nod, r, nn);
cgen(r, &nod);
gmove(&nod, l);
if(nn != Z)
gmove(&nod, nn);
regfree(&nod);
} else
gmove(r, l);
break;
}
if(l->complex >= r->complex) {
if(l->op == OINDEX && immconst(r)) {
gmove(r, l);
break;
}
reglcgen(&nod1, l, Z);
if(r->addable >= INDEXED && !hardconst(r)) {
gmove(r, &nod1);
if(nn != Z)
gmove(r, nn);
regfree(&nod1);
break;
}
regalloc(&nod, r, nn);
cgen(r, &nod);
} else {
regalloc(&nod, r, nn);
cgen(r, &nod);
reglcgen(&nod1, l, Z);
}
gmove(&nod, &nod1);
regfree(&nod);
regfree(&nod1);
break;
bitas:
n = l->left;
regalloc(&nod, r, nn);
if(l->complex >= r->complex) {
reglcgen(&nod1, n, Z);
cgen(r, &nod);
} else {
cgen(r, &nod);
reglcgen(&nod1, n, Z);
}
regalloc(&nod2, n, Z);
gmove(&nod1, &nod2);
bitstore(l, &nod, &nod1, &nod2, nn);
break;
case OBIT:
if(nn == Z) {
nullwarn(l, Z);
break;
}
bitload(n, &nod, Z, Z, nn);
gmove(&nod, nn);
regfree(&nod);
break;
case OLSHR:
case OASHL:
case OASHR:
if(nn == Z) {
nullwarn(l, r);
break;
}
if(r->op == OCONST) {
if(r->vconst == 0) {
cgen(l, nn);
break;
}
regalloc(&nod, l, nn);
cgen(l, &nod);
if(o == OASHL && r->vconst == 1)
gopcode(OADD, n->type, &nod, &nod);
else
gopcode(o, n->type, r, &nod);
gmove(&nod, nn);
regfree(&nod);
break;
}
/*
* get nod to be D_CX
*/
if(nodreg(&nod, nn, D_CX)) {
regsalloc(&nod1, n);
gmove(&nod, &nod1);
cgen(n, &nod); /* probably a bug */
gmove(&nod, nn);
gmove(&nod1, &nod);
break;
}
reg[D_CX]++;
if(nn->op == OREGISTER && nn->reg == D_CX)
regalloc(&nod1, l, Z);
else
regalloc(&nod1, l, nn);
if(r->complex >= l->complex) {
cgen(r, &nod);
cgen(l, &nod1);
} else {
cgen(l, &nod1);
cgen(r, &nod);
}
gopcode(o, n->type, &nod, &nod1);
gmove(&nod1, nn);
regfree(&nod);
regfree(&nod1);
break;
case OADD:
case OSUB:
case OOR:
case OXOR:
case OAND:
if(nn == Z) {
nullwarn(l, r);
break;
}
if(typefd[n->type->etype])
goto fop;
if(r->op == OCONST) {
if(r->vconst == 0 && o != OAND) {
cgen(l, nn);
break;
}
}
if(n->op == OADD && l->op == OASHL && l->right->op == OCONST
&& (r->op != OCONST || r->vconst < -128 || r->vconst > 127)) {
c = l->right->vconst;
if(c > 0 && c <= 3) {
if(l->left->complex >= r->complex) {
regalloc(&nod, l->left, nn);
cgen(l->left, &nod);
if(r->addable < INDEXED) {
regalloc(&nod1, r, Z);
cgen(r, &nod1);
genmuladd(&nod, &nod, 1 << c, &nod1);
regfree(&nod1);
}
else
genmuladd(&nod, &nod, 1 << c, r);
}
else {
regalloc(&nod, r, nn);
cgen(r, &nod);
regalloc(&nod1, l->left, Z);
cgen(l->left, &nod1);
genmuladd(&nod, &nod1, 1 << c, &nod);
regfree(&nod1);
}
gmove(&nod, nn);
regfree(&nod);
break;
}
}
if(r->addable >= INDEXED && !hardconst(r)) {
regalloc(&nod, l, nn);
cgen(l, &nod);
gopcode(o, n->type, r, &nod);
gmove(&nod, nn);
regfree(&nod);
break;
}
if(l->complex >= r->complex) {
regalloc(&nod, l, nn);
cgen(l, &nod);
regalloc(&nod1, r, Z);
cgen(r, &nod1);
gopcode(o, n->type, &nod1, &nod);
} else {
regalloc(&nod1, r, nn);
cgen(r, &nod1);
regalloc(&nod, l, Z);
cgen(l, &nod);
gopcode(o, n->type, &nod1, &nod);
}
gmove(&nod, nn);
regfree(&nod);
regfree(&nod1);
break;
case OLMOD:
case OMOD:
case OLMUL:
case OLDIV:
case OMUL:
case ODIV:
if(nn == Z) {
nullwarn(l, r);
break;
}
if(typefd[n->type->etype])
goto fop;
if(r->op == OCONST && typechl[n->type->etype]) { /* TO DO */
SET(v);
switch(o) {
case ODIV:
case OMOD:
c = r->vconst;
if(c < 0)
c = -c;
v = xlog2(c);
if(v < 0)
break;
/* fall thru */
case OMUL:
case OLMUL:
regalloc(&nod, l, nn);
cgen(l, &nod);
switch(o) {
case OMUL:
case OLMUL:
mulgen(n->type, r, &nod);
break;
case ODIV:
sdiv2(r->vconst, v, l, &nod);
break;
case OMOD:
smod2(r->vconst, v, l, &nod);
break;
}
gmove(&nod, nn);
regfree(&nod);
goto done;
case OLDIV:
c = r->vconst;
if((c & 0x80000000) == 0)
break;
regalloc(&nod1, l, Z);
cgen(l, &nod1);
regalloc(&nod, l, nn);
zeroregm(&nod);
gins(ACMPL, &nod1, nodconst(c));
gins(ASBBL, nodconst(-1), &nod);
regfree(&nod1);
gmove(&nod, nn);
regfree(&nod);
goto done;
}
}
if(o == OMUL) {
if(l->addable >= INDEXED) {
t = l;
l = r;
r = t;
}
/* should favour AX */
regalloc(&nod, l, nn);
cgen(l, &nod);
if(r->addable < INDEXED || hardconst(r)) {
regalloc(&nod1, r, Z);
cgen(r, &nod1);
gopcode(OMUL, n->type, &nod1, &nod);
regfree(&nod1);
}else
gopcode(OMUL, n->type, r, &nod); /* addressible */
gmove(&nod, nn);
regfree(&nod);
break;
}
/*
* get nod to be D_AX
* get nod1 to be D_DX
*/
if(nodreg(&nod, nn, D_AX)) {
regsalloc(&nod2, n);
gmove(&nod, &nod2);
v = reg[D_AX];
reg[D_AX] = 0;
if(isreg(l, D_AX)) {
nod3 = *n;
nod3.left = &nod2;
cgen(&nod3, nn);
} else
if(isreg(r, D_AX)) {
nod3 = *n;
nod3.right = &nod2;
cgen(&nod3, nn);
} else
cgen(n, nn);
gmove(&nod2, &nod);
reg[D_AX] = v;
break;
}
if(nodreg(&nod1, nn, D_DX)) {
regsalloc(&nod2, n);
gmove(&nod1, &nod2);
v = reg[D_DX];
reg[D_DX] = 0;
if(isreg(l, D_DX)) {
nod3 = *n;
nod3.left = &nod2;
cgen(&nod3, nn);
} else
if(isreg(r, D_DX)) {
nod3 = *n;
nod3.right = &nod2;
cgen(&nod3, nn);
} else
cgen(n, nn);
gmove(&nod2, &nod1);
reg[D_DX] = v;
break;
}
reg[D_AX]++;
if(r->op == OCONST && (o == ODIV || o == OLDIV) && immconst(r) && typechl[r->type->etype]) {
reg[D_DX]++;
if(l->addable < INDEXED) {
regalloc(&nod2, l, Z);
cgen(l, &nod2);
l = &nod2;
}
if(o == ODIV)
sdivgen(l, r, &nod, &nod1);
else
udivgen(l, r, &nod, &nod1);
gmove(&nod1, nn);
if(l == &nod2)
regfree(l);
goto freeaxdx;
}
if(l->complex >= r->complex) {
cgen(l, &nod);
reg[D_DX]++;
if(o == ODIV || o == OMOD)
gins(typechl[l->type->etype]? ACDQ: ACQO, Z, Z);
if(o == OLDIV || o == OLMOD)
zeroregm(&nod1);
if(r->addable < INDEXED || r->op == OCONST) {
regsalloc(&nod3, r);
cgen(r, &nod3);
gopcode(o, n->type, &nod3, Z);
} else
gopcode(o, n->type, r, Z);
} else {
regsalloc(&nod3, r);
cgen(r, &nod3);
cgen(l, &nod);
reg[D_DX]++;
if(o == ODIV || o == OMOD)
gins(typechl[l->type->etype]? ACDQ: ACQO, Z, Z);
if(o == OLDIV || o == OLMOD)
zeroregm(&nod1);
gopcode(o, n->type, &nod3, Z);
}
if(o == OMOD || o == OLMOD)
gmove(&nod1, nn);
else
gmove(&nod, nn);
freeaxdx:
regfree(&nod);
regfree(&nod1);
break;
case OASLSHR:
case OASASHL:
case OASASHR:
if(r->op == OCONST)
goto asand;
if(l->op == OBIT)
goto asbitop;
if(typefd[n->type->etype])
goto asand; /* can this happen? */
/*
* get nod to be D_CX
*/
if(nodreg(&nod, nn, D_CX)) {
regsalloc(&nod1, n);
gmove(&nod, &nod1);
cgen(n, &nod);
if(nn != Z)
gmove(&nod, nn);
gmove(&nod1, &nod);
break;
}
reg[D_CX]++;
if(r->complex >= l->complex) {
cgen(r, &nod);
if(hardleft)
reglcgen(&nod1, l, Z);
else
nod1 = *l;
} else {
if(hardleft)
reglcgen(&nod1, l, Z);
else
nod1 = *l;
cgen(r, &nod);
}
gopcode(o, l->type, &nod, &nod1);
regfree(&nod);
if(nn != Z)
gmove(&nod1, nn);
if(hardleft)
regfree(&nod1);
break;
case OASAND:
case OASADD:
case OASSUB:
case OASXOR:
case OASOR:
asand:
if(l->op == OBIT)
goto asbitop;
if(typefd[l->type->etype] || typefd[r->type->etype])
goto asfop;
if(l->complex >= r->complex) {
if(hardleft)
reglcgen(&nod, l, Z);
else
nod = *l;
if(!immconst(r)) {
regalloc(&nod1, r, nn);
cgen(r, &nod1);
gopcode(o, l->type, &nod1, &nod);
regfree(&nod1);
} else
gopcode(o, l->type, r, &nod);
} else {
regalloc(&nod1, r, nn);
cgen(r, &nod1);
if(hardleft)
reglcgen(&nod, l, Z);
else
nod = *l;
gopcode(o, l->type, &nod1, &nod);
regfree(&nod1);
}
if(nn != Z)
gmove(&nod, nn);
if(hardleft)
regfree(&nod);
break;
asfop:
if(l->complex >= r->complex) {
if(hardleft)
reglcgen(&nod, l, Z);
else
nod = *l;
if(r->addable < INDEXED){
regalloc(&nod1, r, nn);
cgen(r, &nod1);
}else
nod1 = *r;
regalloc(&nod2, r, Z);
gmove(&nod, &nod2);
gopcode(o, r->type, &nod1, &nod2);
gmove(&nod2, &nod);
regfree(&nod2);
if(r->addable < INDEXED)
regfree(&nod1);
} else {
regalloc(&nod1, r, nn);
cgen(r, &nod1);
if(hardleft)
reglcgen(&nod, l, Z);
else
nod = *l;
if(o != OASMUL && o != OASADD) {
regalloc(&nod2, r, Z);
gmove(&nod, &nod2);
gopcode(o, r->type, &nod1, &nod2);
regfree(&nod1);
gmove(&nod2, &nod);
regfree(&nod2);
} else {
gopcode(o, r->type, &nod, &nod1);
gmove(&nod1, &nod);
regfree(&nod1);
}
}
if(nn != Z)
gmove(&nod, nn);
if(hardleft)
regfree(&nod);
break;
case OASLMUL:
case OASLDIV:
case OASLMOD:
case OASMUL:
case OASDIV:
case OASMOD:
if(l->op == OBIT)
goto asbitop;
if(typefd[n->type->etype] || typefd[r->type->etype])
goto asfop;
if(r->op == OCONST && typechl[n->type->etype]) {
SET(v);
switch(o) {
case OASDIV:
case OASMOD:
c = r->vconst;
if(c < 0)
c = -c;
v = xlog2(c);
if(v < 0)
break;
/* fall thru */
case OASMUL:
case OASLMUL:
if(hardleft)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
regalloc(&nod, l, nn);
cgen(&nod2, &nod);
switch(o) {
case OASMUL:
case OASLMUL:
mulgen(n->type, r, &nod);
break;
case OASDIV:
sdiv2(r->vconst, v, l, &nod);
break;
case OASMOD:
smod2(r->vconst, v, l, &nod);
break;
}
havev:
gmove(&nod, &nod2);
if(nn != Z)
gmove(&nod, nn);
if(hardleft)
regfree(&nod2);
regfree(&nod);
goto done;
case OASLDIV:
c = r->vconst;
if((c & 0x80000000) == 0)
break;
if(hardleft)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
regalloc(&nod1, l, nn);
cgen(&nod2, &nod1);
regalloc(&nod, l, nn);
zeroregm(&nod);
gins(ACMPL, &nod1, nodconst(c));
gins(ASBBL, nodconst(-1), &nod);
regfree(&nod1);
goto havev;
}
}
if(o == OASMUL) {
/* should favour AX */
regalloc(&nod, l, nn);
if(r->complex >= FNX) {
regalloc(&nod1, r, Z);
cgen(r, &nod1);
r = &nod1;
}
if(hardleft)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
cgen(&nod2, &nod);
if(r->addable < INDEXED || hardconst(r)) {
if(r->complex < FNX) {
regalloc(&nod1, r, Z);
cgen(r, &nod1);
}
gopcode(OASMUL, n->type, &nod1, &nod);
regfree(&nod1);
}
else
gopcode(OASMUL, n->type, r, &nod);
if(r == &nod1)
regfree(r);
gmove(&nod, &nod2);
if(nn != Z)
gmove(&nod, nn);
regfree(&nod);
if(hardleft)
regfree(&nod2);
break;
}
/*
* get nod to be D_AX
* get nod1 to be D_DX
*/
if(nodreg(&nod, nn, D_AX)) {
regsalloc(&nod2, n);
gmove(&nod, &nod2);
v = reg[D_AX];
reg[D_AX] = 0;
if(isreg(l, D_AX)) {
nod3 = *n;
nod3.left = &nod2;
cgen(&nod3, nn);
} else
if(isreg(r, D_AX)) {
nod3 = *n;
nod3.right = &nod2;
cgen(&nod3, nn);
} else
cgen(n, nn);
gmove(&nod2, &nod);
reg[D_AX] = v;
break;
}
if(nodreg(&nod1, nn, D_DX)) {
regsalloc(&nod2, n);
gmove(&nod1, &nod2);
v = reg[D_DX];
reg[D_DX] = 0;
if(isreg(l, D_DX)) {
nod3 = *n;
nod3.left = &nod2;
cgen(&nod3, nn);
} else
if(isreg(r, D_DX)) {
nod3 = *n;
nod3.right = &nod2;
cgen(&nod3, nn);
} else
cgen(n, nn);
gmove(&nod2, &nod1);
reg[D_DX] = v;
break;
}
reg[D_AX]++;
reg[D_DX]++;
if(l->complex >= r->complex) {
if(hardleft)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
cgen(&nod2, &nod);
if(r->op == OCONST && typechl[r->type->etype]) {
switch(o) {
case OASDIV:
sdivgen(&nod2, r, &nod, &nod1);
goto divdone;
case OASLDIV:
udivgen(&nod2, r, &nod, &nod1);
divdone:
gmove(&nod1, &nod2);
if(nn != Z)
gmove(&nod1, nn);
goto freelxaxdx;
}
}
if(o == OASDIV || o == OASMOD)
gins(typechl[l->type->etype]? ACDQ: ACQO, Z, Z);
if(o == OASLDIV || o == OASLMOD)
zeroregm(&nod1);
if(r->addable < INDEXED || r->op == OCONST ||
!typeil[r->type->etype]) {
regalloc(&nod3, r, Z);
cgen(r, &nod3);
gopcode(o, l->type, &nod3, Z);
regfree(&nod3);
} else
gopcode(o, n->type, r, Z);
} else {
regalloc(&nod3, r, Z);
cgen(r, &nod3);
if(hardleft)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
cgen(&nod2, &nod);
if(o == OASDIV || o == OASMOD)
gins(typechl[l->type->etype]? ACDQ: ACQO, Z, Z);
if(o == OASLDIV || o == OASLMOD)
zeroregm(&nod1);
gopcode(o, l->type, &nod3, Z);
regfree(&nod3);
}
if(o == OASMOD || o == OASLMOD) {
gmove(&nod1, &nod2);
if(nn != Z)
gmove(&nod1, nn);
} else {
gmove(&nod, &nod2);
if(nn != Z)
gmove(&nod, nn);
}
freelxaxdx:
if(hardleft)
regfree(&nod2);
regfree(&nod);
regfree(&nod1);
break;
fop:
if(l->complex >= r->complex) {
regalloc(&nod, l, nn);
cgen(l, &nod);
if(r->addable < INDEXED) {
regalloc(&nod1, r, Z);
cgen(r, &nod1);
gopcode(o, n->type, &nod1, &nod);
regfree(&nod1);
} else
gopcode(o, n->type, r, &nod);
} else {
/* TO DO: could do better with r->addable >= INDEXED */
regalloc(&nod1, r, Z);
cgen(r, &nod1);
regalloc(&nod, l, nn);
cgen(l, &nod);
gopcode(o, n->type, &nod1, &nod);
regfree(&nod1);
}
gmove(&nod, nn);
regfree(&nod);
break;
asbitop:
regalloc(&nod4, n, nn);
if(l->complex >= r->complex) {
bitload(l, &nod, &nod1, &nod2, &nod4);
regalloc(&nod3, r, Z);
cgen(r, &nod3);
} else {
regalloc(&nod3, r, Z);
cgen(r, &nod3);
bitload(l, &nod, &nod1, &nod2, &nod4);
}
gmove(&nod, &nod4);
{ /* TO DO: check floating point source */
Node onod;
/* incredible grot ... */
onod = nod3;
onod.op = o;
onod.complex = 2;
onod.addable = 0;
onod.type = tfield;
onod.left = &nod4;
onod.right = &nod3;
cgen(&onod, Z);
}
regfree(&nod3);
gmove(&nod4, &nod);
regfree(&nod4);
bitstore(l, &nod, &nod1, &nod2, nn);
break;
case OADDR:
if(nn == Z) {
nullwarn(l, Z);
break;
}
lcgen(l, nn);
break;
case OFUNC:
if(l->complex >= FNX) {
if(l->op != OIND)
diag(n, "bad function call");
regret(&nod, l->left);
cgen(l->left, &nod);
regsalloc(&nod1, l->left);
gmove(&nod, &nod1);
regfree(&nod);
nod = *n;
nod.left = &nod2;
nod2 = *l;
nod2.left = &nod1;
nod2.complex = 1;
cgen(&nod, nn);
return;
}
o = 0;
if(REGARG >= 0)
o = reg[REGARG];
gargs(r, &nod, &nod1);
if(l->addable < INDEXED) {
reglcgen(&nod, l, nn);
nod.op = OREGISTER;
gopcode(OFUNC, n->type, Z, &nod);
regfree(&nod);
} else
gopcode(OFUNC, n->type, Z, l);
if(REGARG >= 0)
if(o != reg[REGARG])
reg[REGARG]--;
if(nn != Z) {
regret(&nod, n);
gmove(&nod, nn);
regfree(&nod);
}
break;
case OIND:
if(nn == Z) {
nullwarn(l, Z);
break;
}
regialloc(&nod, n, nn);
r = l;
while(r->op == OADD)
r = r->right;
if(sconst(r)) {
v = r->vconst;
r->vconst = 0;
cgen(l, &nod);
nod.xoffset += v;
r->vconst = v;
} else
cgen(l, &nod);
regind(&nod, n);
gmove(&nod, nn);
regfree(&nod);
break;
case OEQ:
case ONE:
case OLE:
case OLT:
case OGE:
case OGT:
case OLO:
case OLS:
case OHI:
case OHS:
if(nn == Z) {
nullwarn(l, r);
break;
}
boolgen(n, 1, nn);
break;
case OANDAND:
case OOROR:
boolgen(n, 1, nn);
if(nn == Z)
patch(p, pc);
break;
case ONOT:
if(nn == Z) {
nullwarn(l, Z);
break;
}
boolgen(n, 1, nn);
break;
case OCOMMA:
cgen(l, Z);
cgen(r, nn);
break;
case OCAST:
if(nn == Z) {
nullwarn(l, Z);
break;
}
/*
* convert from types l->n->nn
*/
if(nocast(l->type, n->type) && nocast(n->type, nn->type)) {
/* both null, gen l->nn */
cgen(l, nn);
break;
}
if(ewidth[n->type->etype] < ewidth[l->type->etype]){
if(l->type->etype == TIND && typechlp[n->type->etype])
warn(n, "conversion of pointer to shorter integer");
}else if(0){
if(nocast(n->type, nn->type) || castup(n->type, nn->type)){
if(typefd[l->type->etype] != typefd[nn->type->etype])
regalloc(&nod, l, nn);
else
regalloc(&nod, nn, nn);
cgen(l, &nod);
gmove(&nod, nn);
regfree(&nod);
break;
}
}
regalloc(&nod, l, nn);
cgen(l, &nod);
regalloc(&nod1, n, &nod);
gmove(&nod, &nod1);
gmove(&nod1, nn);
regfree(&nod1);
regfree(&nod);
break;
case ODOT:
sugen(l, nodrat, l->type->width);
if(nn == Z)
break;
warn(n, "non-interruptable temporary");
nod = *nodrat;
if(!r || r->op != OCONST) {
diag(n, "DOT and no offset");
break;
}
nod.xoffset += (int32)r->vconst;
nod.type = n->type;
cgen(&nod, nn);
break;
case OCOND:
bcgen(l, 1);
p1 = p;
cgen(r->left, nn);
gbranch(OGOTO);
patch(p1, pc);
p1 = p;
cgen(r->right, nn);
patch(p1, pc);
break;
case OPOSTINC:
case OPOSTDEC:
v = 1;
if(l->type->etype == TIND)
v = l->type->link->width;
if(o == OPOSTDEC)
v = -v;
if(l->op == OBIT)
goto bitinc;
if(nn == Z)
goto pre;
if(hardleft)
reglcgen(&nod, l, Z);
else
nod = *l;
gmove(&nod, nn);
if(typefd[n->type->etype]) {
regalloc(&nod1, l, Z);
gmove(&nod, &nod1);
if(v < 0)
gopcode(OSUB, n->type, nodfconst(-v), &nod1);
else
gopcode(OADD, n->type, nodfconst(v), &nod1);
gmove(&nod1, &nod);
regfree(&nod1);
} else
gopcode(OADD, n->type, nodconst(v), &nod);
if(hardleft)
regfree(&nod);
break;
case OPREINC:
case OPREDEC:
v = 1;
if(l->type->etype == TIND)
v = l->type->link->width;
if(o == OPREDEC)
v = -v;
if(l->op == OBIT)
goto bitinc;
pre:
if(hardleft)
reglcgen(&nod, l, Z);
else
nod = *l;
if(typefd[n->type->etype]) {
regalloc(&nod1, l, Z);
gmove(&nod, &nod1);
if(v < 0)
gopcode(OSUB, n->type, nodfconst(-v), &nod1);
else
gopcode(OADD, n->type, nodfconst(v), &nod1);
gmove(&nod1, &nod);
regfree(&nod1);
} else
gopcode(OADD, n->type, nodconst(v), &nod);
if(nn != Z)
gmove(&nod, nn);
if(hardleft)
regfree(&nod);
break;
bitinc:
if(nn != Z && (o == OPOSTINC || o == OPOSTDEC)) {
bitload(l, &nod, &nod1, &nod2, Z);
gmove(&nod, nn);
gopcode(OADD, tfield, nodconst(v), &nod);
bitstore(l, &nod, &nod1, &nod2, Z);
break;
}
bitload(l, &nod, &nod1, &nod2, nn);
gopcode(OADD, tfield, nodconst(v), &nod);
bitstore(l, &nod, &nod1, &nod2, nn);
break;
}
done:
cursafe = curs;
}
void
swit2(C1 *q, int nc, int32 def, Node *n)
{
C1 *r;
int i;
int32 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 = %.8ux\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 > %.8ux\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);
if(debug['W'])
print("case < %.8ux\n", r->val);
patch(sp, pc);
swit2(r+1, nc-i-1, def, n);
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 = %.8ux\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 gstart(void) {
gbranch(CodeStart);
}
// Generate function prolog of type 't'
void gfunc_prolog(CType *func_type) {
int addr, align, size, func_call, fastcall_nb_regs;
int param_index, param_addr;
uint8_t *fastcall_regs_ptr;
Sym *sym;
CType *type;
#ifdef DEBUG_BRANCH
printf("compile %s\n", func_name);
#endif
reset_code_buf();
gbranch(CodeStart);
sym = func_type->ref;
func_naked = FUNC_NAKED(sym->r);
func_call = FUNC_CALL(sym->r);
addr = 8;
loc = 0;
regs_used = 0;
if (func_call >= FUNC_FASTCALL1 && func_call <= FUNC_FASTCALL3) {
fastcall_nb_regs = func_call - FUNC_FASTCALL1 + 1;
fastcall_regs_ptr = fastcall_regs;
} else if (func_call == FUNC_FASTCALLW) {
fastcall_nb_regs = 2;
fastcall_regs_ptr = fastcallw_regs;
} else {
fastcall_nb_regs = 0;
fastcall_regs_ptr = NULL;
}
param_index = 0;
// If the function returns a structure, then add an implicit pointer parameter
func_vt = sym->type;
if ((func_vt.t & VT_BTYPE) == VT_STRUCT) {
// TODO: fastcall case?
func_vc = addr;
addr += 4;
param_index++;
}
// Define parameters
while ((sym = sym->next) != NULL) {
type = &sym->type;
size = type_size(type, &align);
size = (size + 3) & ~3;
if (param_index < fastcall_nb_regs) {
// Save FASTCALL register
if (!func_naked) {
loc -= 4;
o(0x89); // movl
gen_modrm(fastcall_regs_ptr[param_index], VT_LOCAL, NULL, loc);
param_addr = loc;
}
} else {
param_addr = addr;
addr += size;
}
sym_push(sym->v & ~SYM_FIELD, type, VT_LOCAL | VT_LVAL, param_addr);
param_index++;
}
// pascal type call?
func_ret_sub = 0;
if (func_call == FUNC_STDCALL) func_ret_sub = addr - 8;
func_noargs = (addr == 8);
}
void gend(void) {
gbranch(CodeEnd);
}
void
cgen(Node *n, Node *nn)
{
Node *l, *r;
Prog *p1;
Node nod, nod1, nod2, nod3, nod4;
int o;
long v, curs;
if(debug['g']) {
prtree(nn, "cgen lhs");
prtree(n, "cgen");
}
if(n == Z || n->type == T)
return;
if(typesuv[n->type->etype]) {
sugen(n, nn, n->type->width);
return;
}
l = n->left;
r = n->right;
o = n->op;
if(n->addable >= INDEXED) {
if(nn == Z) {
switch(o) {
default:
nullwarn(Z, Z);
break;
case OINDEX:
nullwarn(l, r);
break;
}
return;
}
gmove(n, nn);
return;
}
curs = cursafe;
if(n->complex >= FNX)
if(l->complex >= FNX)
if(r != Z && r->complex >= FNX)
switch(o) {
default:
regret(&nod, r);
cgen(r, &nod);
regsalloc(&nod1, r);
gopcode(OAS, &nod, Z, &nod1);
regfree(&nod);
nod = *n;
nod.right = &nod1;
cgen(&nod, nn);
return;
case OFUNC:
case OCOMMA:
case OANDAND:
case OOROR:
case OCOND:
case ODOT:
break;
}
switch(o) {
default:
diag(n, "unknown op in cgen: %O", o);
break;
case OAS:
if(l->op == OBIT)
goto bitas;
if(l->addable >= INDEXED && l->complex < FNX) {
if(nn != Z || r->addable < INDEXED) {
if(r->complex >= FNX && nn == Z)
regret(&nod, r);
else
regalloc(&nod, r, nn);
cgen(r, &nod);
gmove(&nod, l);
if(nn != Z)
gmove(&nod, nn);
regfree(&nod);
} else
gmove(r, l);
break;
}
if(l->complex >= r->complex) {
reglcgen(&nod1, l, Z);
if(r->addable >= INDEXED) {
gmove(r, &nod1);
if(nn != Z)
gmove(r, nn);
regfree(&nod1);
break;
}
regalloc(&nod, r, nn);
cgen(r, &nod);
} else {
regalloc(&nod, r, nn);
cgen(r, &nod);
reglcgen(&nod1, l, Z);
}
gmove(&nod, &nod1);
regfree(&nod);
regfree(&nod1);
break;
bitas:
n = l->left;
regalloc(&nod, r, nn);
if(l->complex >= r->complex) {
reglcgen(&nod1, n, Z);
cgen(r, &nod);
} else {
cgen(r, &nod);
reglcgen(&nod1, n, Z);
}
regalloc(&nod2, n, Z);
gopcode(OAS, &nod1, Z, &nod2);
bitstore(l, &nod, &nod1, &nod2, nn);
break;
case OBIT:
if(nn == Z) {
nullwarn(l, Z);
break;
}
bitload(n, &nod, Z, Z, nn);
gopcode(OAS, &nod, Z, nn);
regfree(&nod);
break;
case OADD:
case OSUB:
case OAND:
case OOR:
case OXOR:
case OLSHR:
case OASHL:
case OASHR:
/*
* immediate operands
*/
if(nn != Z)
if(r->op == OCONST)
if(!typefd[n->type->etype]) {
cgen(l, nn);
if(r->vconst == 0)
if(o != OAND)
break;
if(nn != Z)
gopcode(o, r, Z, nn);
break;
}
case OLMUL:
case OLDIV:
case OLMOD:
case OMUL:
case ODIV:
case OMOD:
if(nn == Z) {
nullwarn(l, r);
break;
}
if(o == OMUL || o == OLMUL) {
if(mulcon(n, nn))
break;
}
if(l->complex >= r->complex) {
regalloc(&nod, l, nn);
cgen(l, &nod);
regalloc(&nod1, r, Z);
cgen(r, &nod1);
gopcode(o, &nod1, Z, &nod);
} else {
regalloc(&nod, r, nn);
cgen(r, &nod);
regalloc(&nod1, l, Z);
cgen(l, &nod1);
gopcode(o, &nod, &nod1, &nod);
}
gopcode(OAS, &nod, Z, nn);
regfree(&nod);
regfree(&nod1);
break;
case OASLSHR:
case OASASHL:
case OASASHR:
case OASAND:
case OASADD:
case OASSUB:
case OASXOR:
case OASOR:
if(l->op == OBIT)
goto asbitop;
if(r->op == OCONST)
if(!typefd[r->type->etype])
if(!typefd[n->type->etype]) {
if(l->addable < INDEXED)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
regalloc(&nod, r, nn);
gopcode(OAS, &nod2, Z, &nod);
gopcode(o, r, Z, &nod);
gopcode(OAS, &nod, Z, &nod2);
regfree(&nod);
if(l->addable < INDEXED)
regfree(&nod2);
break;
}
case OASLMUL:
case OASLDIV:
case OASLMOD:
case OASMUL:
case OASDIV:
case OASMOD:
if(l->op == OBIT)
goto asbitop;
if(l->complex >= r->complex) {
if(l->addable < INDEXED)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
regalloc(&nod1, r, Z);
cgen(r, &nod1);
} else {
regalloc(&nod1, r, Z);
cgen(r, &nod1);
if(l->addable < INDEXED)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
}
regalloc(&nod, n, nn);
gmove(&nod2, &nod);
gopcode(o, &nod1, Z, &nod);
gmove(&nod, &nod2);
if(nn != Z)
gopcode(OAS, &nod, Z, nn);
regfree(&nod);
regfree(&nod1);
if(l->addable < INDEXED)
regfree(&nod2);
break;
asbitop:
regalloc(&nod4, n, nn);
if(l->complex >= r->complex) {
bitload(l, &nod, &nod1, &nod2, &nod4);
regalloc(&nod3, r, Z);
cgen(r, &nod3);
} else {
regalloc(&nod3, r, Z);
cgen(r, &nod3);
bitload(l, &nod, &nod1, &nod2, &nod4);
}
gmove(&nod, &nod4);
gopcode(o, &nod3, Z, &nod4);
regfree(&nod3);
gmove(&nod4, &nod);
regfree(&nod4);
bitstore(l, &nod, &nod1, &nod2, nn);
break;
case OADDR:
if(nn == Z) {
nullwarn(l, Z);
break;
}
lcgen(l, nn);
break;
case OFUNC:
if(l->complex >= FNX) {
if(l->op != OIND)
diag(n, "bad function call");
regret(&nod, l->left);
cgen(l->left, &nod);
regsalloc(&nod1, l->left);
gopcode(OAS, &nod, Z, &nod1);
regfree(&nod);
nod = *n;
nod.left = &nod2;
nod2 = *l;
nod2.left = &nod1;
nod2.complex = 1;
cgen(&nod, nn);
return;
}
o = reg[REGARG];
gargs(r, &nod, &nod1);
if(l->addable < INDEXED) {
reglcgen(&nod, l, Z);
gopcode(OFUNC, Z, Z, &nod);
regfree(&nod);
} else
gopcode(OFUNC, Z, Z, l);
if(REGARG)
if(o != reg[REGARG])
reg[REGARG]--;
if(nn != Z) {
regret(&nod, n);
gopcode(OAS, &nod, Z, nn);
regfree(&nod);
}
break;
case OIND:
if(nn == Z) {
nullwarn(l, Z);
break;
}
regialloc(&nod, n, nn);
r = l;
while(r->op == OADD)
r = r->right;
if(sconst(r)) {
v = r->vconst;
r->vconst = 0;
cgen(l, &nod);
nod.xoffset += v;
r->vconst = v;
} else
cgen(l, &nod);
regind(&nod, n);
gopcode(OAS, &nod, Z, nn);
regfree(&nod);
break;
case OEQ:
case ONE:
case OLE:
case OLT:
case OGE:
case OGT:
case OLO:
case OLS:
case OHI:
case OHS:
if(nn == Z) {
nullwarn(l, r);
break;
}
boolgen(n, 1, nn);
break;
case OANDAND:
case OOROR:
boolgen(n, 1, nn);
if(nn == Z)
patch(p, pc);
break;
case ONOT:
if(nn == Z) {
nullwarn(l, Z);
break;
}
boolgen(n, 1, nn);
break;
case OCOMMA:
cgen(l, Z);
cgen(r, nn);
break;
case OCAST:
if(nn == Z) {
nullwarn(l, Z);
break;
}
/*
* convert from types l->n->nn
*/
if(nocast(l->type, n->type)) {
if(nocast(n->type, nn->type)) {
cgen(l, nn);
break;
}
}
regalloc(&nod, l, nn);
cgen(l, &nod);
regalloc(&nod1, n, &nod);
gopcode(OAS, &nod, Z, &nod1);
gopcode(OAS, &nod1, Z, nn);
regfree(&nod1);
regfree(&nod);
break;
case ODOT:
sugen(l, nodrat, l->type->width);
if(nn != Z) {
warn(n, "non-interruptable temporary");
nod = *nodrat;
if(!r || r->op != OCONST) {
diag(n, "DOT and no offset");
break;
}
nod.xoffset += (long)r->vconst;
nod.type = n->type;
cgen(&nod, nn);
}
break;
case OCOND:
bcgen(l, 1);
p1 = p;
cgen(r->left, nn);
gbranch(OGOTO);
patch(p1, pc);
p1 = p;
cgen(r->right, nn);
patch(p1, pc);
break;
case OPOSTINC:
case OPOSTDEC:
v = 1;
if(l->type->etype == TIND)
v = l->type->link->width;
if(o == OPOSTDEC)
v = -v;
if(l->op == OBIT)
goto bitinc;
if(nn == Z)
goto pre;
if(l->addable < INDEXED)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
regalloc(&nod, l, nn);
gopcode(OAS, &nod2, Z, &nod);
regalloc(&nod1, l, Z);
if(typefd[l->type->etype]) {
regalloc(&nod3, l, Z);
if(v < 0) {
gopcode(OAS, nodfconst(-v), Z, &nod3);
gopcode(OSUB, &nod3, &nod, &nod1);
} else {
gopcode(OAS, nodfconst(v), Z, &nod3);
gopcode(OADD, &nod3, &nod, &nod1);
}
regfree(&nod3);
} else
gopcode(OADD, nodconst(v), &nod, &nod1);
gopcode(OAS, &nod1, Z, &nod2);
regfree(&nod);
regfree(&nod1);
if(l->addable < INDEXED)
regfree(&nod2);
break;
case OPREINC:
case OPREDEC:
v = 1;
if(l->type->etype == TIND)
v = l->type->link->width;
if(o == OPREDEC)
v = -v;
if(l->op == OBIT)
goto bitinc;
pre:
if(l->addable < INDEXED)
reglcgen(&nod2, l, Z);
else
nod2 = *l;
regalloc(&nod, l, nn);
gopcode(OAS, &nod2, Z, &nod);
if(typefd[l->type->etype]) {
regalloc(&nod3, l, Z);
if(v < 0) {
gopcode(OAS, nodfconst(-v), Z, &nod3);
gopcode(OSUB, &nod3, Z, &nod);
} else {
gopcode(OAS, nodfconst(v), Z, &nod3);
gopcode(OADD, &nod3, Z, &nod);
}
regfree(&nod3);
} else
gopcode(OADD, nodconst(v), Z, &nod);
gopcode(OAS, &nod, Z, &nod2);
if(nn && l->op == ONAME) /* in x=++i, emit USED(i) */
gins(ANOP, l, Z);
regfree(&nod);
if(l->addable < INDEXED)
regfree(&nod2);
break;
bitinc:
if(nn != Z && (o == OPOSTINC || o == OPOSTDEC)) {
bitload(l, &nod, &nod1, &nod2, Z);
gopcode(OAS, &nod, Z, nn);
gopcode(OADD, nodconst(v), Z, &nod);
bitstore(l, &nod, &nod1, &nod2, Z);
break;
}
bitload(l, &nod, &nod1, &nod2, nn);
gopcode(OADD, nodconst(v), Z, &nod);
bitstore(l, &nod, &nod1, &nod2, nn);
break;
}
cursafe = curs;
}
/* else binary */
void
swit1(C1 *q, int nc, long def, int g, Node *n)
{
C1 *r, *s;
int i, l, m, y;
long v, range;
Prog *sp1, *sp2;
/* note that g and g+1 are not allocated */
if(nc <= N1)
goto linear;
y = 23*nc/100 + 5; /* number of cases needed to make */
if(y < N2) /* direct switch worthwile */
y = N2; /* try to do better than n**2 here */
for(m=nc; m>=y; m--) { /* m is number of cases */
s = q+nc;
r = s-m;
for(l=nc-m; l>=0; l--) { /* l is base of contig cases */
s--;
range = s->val - r->val;
if(range > 0 && range <= N3*m)
goto direct;
r--;
}
}
/*
* divide and conquer
*/
i = nc / 2;
r = q+i;
v = r->val;
/* compare median */
if(v >= -128 && v < 128) {
gopcode(OAS, n->type, D_CONST, nodconst(v), g+1, n);
gopcode(OEQ, n->type, g, n, g+1, n);
} else
gopcode(OEQ, n->type, g, n, D_CONST, nodconst(v));
gbranch(OLT);
sp1 = p;
gbranch(OGT);
sp2 = p;
gbranch(OGOTO);
patch(p, r->label);
patch(sp1, pc);
swit1(q, i, def, g, n);
patch(sp2, pc);
swit1(r+1, nc-i-1, def, g, n);
return;
direct:
/* compare low bound */
v = r->val;
if(v >= -128 && v < 128) {
gopcode(OAS, n->type, D_CONST, nodconst(v), g+1, n);
gopcode(OEQ, n->type, g, n, g+1, n);
} else
gopcode(OEQ, n->type, g, n, D_CONST, nodconst(v));
gbranch(OLT);
sp1 = p;
/* compare high bound */
v = s->val;
if(v >= -128 && v < 128) {
gopcode(OAS, n->type, D_CONST, nodconst(v), g+1, n);
gopcode(OEQ, n->type, g, n, g+1, n);
} else
gopcode(OEQ, n->type, g, n, D_CONST, nodconst(v));
gbranch(OGT);
sp2 = p;
/* switch */
v = r->val;
gpseudo(AMOVW, symstatic, D_R0, 0L);
p->from.offset = nstatic - v*2;
p->from.index = g|I_INDEX1;
p->from.scale = 5;
nextpc();
p->as = ACASEW;
/* table */
for(i=0; i<=range; i++) {
gbranch(OCASE);
if(v == r->val) {
patch(p, r->label);
r++;
} else
patch(p, def);
p->from.type = D_STATIC;
p->from.sym = symstatic;
p->from.offset = nstatic;
nstatic += types[TSHORT]->width;
v++;
}
gbranch(OGOTO);
patch(p, def);
if(r != s+1)
print("smelly direct switch\n");
if(l > 0) {
patch(sp1, pc);
swit1(q, l, def, g, n);
} else
patch(sp1, def);
m += l;
if(m < nc) {
patch(sp2, pc);
swit1(q+m, nc-m, def, g, n);
} else
patch(sp2, def);
return;
linear:
for(i=0; i<nc; i++) {
v = q->val;
if(v >= -128 && v < 128) {
gopcode(OAS, n->type, D_CONST, nodconst(v), g+1, n);
gopcode(OEQ, n->type, g+1, n, g, n);
} else
gopcode(OEQ, n->type, g, n, D_CONST, nodconst(v));
gbranch(OEQ);
patch(p, q->label);
q++;
}
gbranch(OGOTO);
patch(p, def);
}
int glabel(void) {
return gbranch(CodeLabel);
}
