ref: 9f76a7f6819ac04552b4fb6588156f3e4089d1d7
dir: /limbo/typecheck.c/
#include "limbo.h"
#include "y.tab.h"
Node **labstack;
int labdep;
static Node* inexcept;
static Decl* fndec;
void checkraises(Node *n);
static void
increfs(Decl *id)
{
for( ; id != nil; id = id->link)
id->refs++;
}
static int
fninline(Decl *d)
{
Node *n, *left, *right;
left = right = nil;
n = d->init;
if(dontinline || d->caninline < 0 || d->locals != nil || ispoly(d) || n->ty->tof->kind == Tnone || nodes(n) >= 100)
return 0;
n = n->right;
if(n->op == Oseq && n->right == nil)
n = n->left;
/*
* inline
* (a) return e;
* (b) if(c) return e1; else return e2;
* (c) if(c) return e1; return e2;
*/
switch(n->op){
case Oret:
break;
case Oif:
right = n->right;
if(right->right == nil || right->left->op != Oret || right->right->op != Oret || !tequal(right->left->left->ty, right->right->left->ty))
return 0;
break;
case Oseq:
left = n->left;
right = n->right;
if(left->op != Oif || left->right->right != nil || left->right->left->op != Oret || right->op != Oseq || right->right != nil || right->left->op != Oret || !tequal(left->right->left->left->ty, right->left->left->ty))
return 0;
break;
default:
return 0;
}
if(occurs(d, n) || hasasgns(n))
return 0;
if(n->op == Oseq){
left->right->right = right->left;
n = left;
right = n->right;
d->init->right->right = nil;
}
if(n->op == Oif){
n->ty = right->ty = right->left->left->ty;
right->left = right->left->left;
right->right = right->right->left;
d->init->right->left = mkunary(Oret, n);
}
return 1;
}
static int
isfnrefty(Type *t)
{
return t->kind == Tref && t->tof->kind == Tfn;
}
static int
isfnref(Decl *d)
{
switch(d->store){
case Dglobal:
case Darg:
case Dlocal:
case Dfield:
case Dimport:
return isfnrefty(d->ty);
}
return 0;
}
int
argncompat(Node *n, Decl *f, Node *a)
{
for(; a != nil; a = a->right){
if(f == nil){
nerror(n, "%V: too many function arguments", n->left);
return 0;
}
f = f->next;
}
if(f != nil){
nerror(n, "%V: too few function arguments", n->left);
return 0;
}
return 1;
}
static void
rewind(Node *n)
{
Node *r, *nn;
r = n;
nn = n->left;
for(n = n->right; n != nil; n = n->right){
if(n->right == nil){
r->left = nn;
r->right = n->left;
}
else
nn = mkbin(Oindex, nn, n->left);
}
}
static void
ckmod(Node *n, Decl *id)
{
Type *t;
Decl *d, *idc;
Node *mod;
if(id == nil)
fatal("can't find function: %n", n);
idc = nil;
mod = nil;
if(n->op == Oname){
idc = id;
mod = id->eimport;
}
else if(n->op == Omdot)
mod = n->left;
else if(n->op == Odot){
idc = id->dot;
t = n->left->ty;
if(t->kind == Tref)
t = t->tof;
if(t->kind == Tadtpick)
t = t->decl->dot->ty;
d = t->decl;
while(d != nil && d->link != nil)
d = d->link;
if(d != nil && d->timport != nil)
mod = d->timport->eimport;
n->right->left = mod;
}
if(mod != nil && mod->ty->kind != Tmodule){
nerror(n, "cannot use %V as a function reference", n);
return;
}
if(mod != nil){
if(valistype(mod)){
nerror(n, "cannot use %V as a function reference because %V is a module interface", n, mod);
return;
}
}else if(idc != nil && idc->dot != nil && !isimpmod(idc->dot->sym)){
nerror(n, "cannot use %V without importing %s from a variable", n, idc->sym->name);
return;
}
if(mod != nil)
modrefable(n->ty);
}
static void
addref(Node *n)
{
Node *nn;
nn = mkn(0, nil, nil);
*nn = *n;
n->op = Oref;
n->left = nn;
n->right = nil;
n->decl = nil;
n->ty = usetype(mktype(&n->src.start, &n->src.stop, Tref, nn->ty, nil));
}
static void
fnref(Node *n, Decl *id)
{
id->caninline = -1;
ckmod(n, id);
addref(n);
while(id->link != nil)
id = id->link;
if(ispoly(id) && encpolys(id) != nil)
nerror(n, "cannot have a polymorphic adt function reference %s", id->sym->name);
}
Decl*
typecheck(int checkimp)
{
Decl *entry, *m, *d;
Sym *s;
int i;
if(errors)
return nil;
/*
* generate the set of all functions
* compile one function at a time
*/
gdecl(tree);
gbind(tree);
fns = allocmem(nfns * sizeof(Decl));
i = gcheck(tree, fns, 0);
if(i != nfns)
fatal("wrong number of functions found in gcheck");
maxlabdep = 0;
for(i = 0; i < nfns; i++){
d = fns[i];
if(d != nil)
fndec = d;
if(d != nil)
fncheck(d);
fndec = nil;
}
if(errors)
return nil;
entry = nil;
if(checkimp){
Decl *im;
Dlist *dm;
if(impmods == nil){
yyerror("no implementation module");
return nil;
}
for(im = impmods; im != nil; im = im->next){
for(dm = impdecls; dm != nil; dm = dm->next)
if(dm->d->sym == im->sym)
break;
if(dm == nil || dm->d->ty == nil){
yyerror("no definition for implementation module %s", im->sym->name);
return nil;
}
}
/*
* can't check the module spec until all types and imports are determined,
* which happens in scheck
*/
for(dm = impdecls; dm != nil; dm = dm->next){
im = dm->d;
im->refs++;
im->ty = usetype(im->ty);
if(im->store != Dtype || im->ty->kind != Tmodule){
error(im->src.start, "cannot implement %K", im);
return nil;
}
}
/* now check any multiple implementations */
impdecl = modimp(impdecls, impmods);
s = enter("init", 0);
entry = nil;
for(dm = impdecls; dm != nil; dm = dm->next){
im = dm->d;
for(m = im->ty->ids; m != nil; m = m->next){
m->ty = usetype(m->ty);
m->refs++;
if(m->sym == s && m->ty->kind == Tfn && entry == nil)
entry = m;
if(m->store == Dglobal || m->store == Dfn)
modrefable(m->ty);
if(m->store == Dtype && m->ty->kind == Tadt){
for(d = m->ty->ids; d != nil; d = d->next){
d->ty = usetype(d->ty);
modrefable(d->ty);
d->refs++;
}
}
}
checkrefs(im->ty->ids);
}
}
if(errors)
return nil;
gsort(tree);
tree = nil;
return entry;
}
/*
* introduce all global declarations
* also adds all fields to adts and modules
* note the complications due to nested Odas expressions
*/
void
gdecl(Node *n)
{
for(;;){
if(n == nil)
return;
if(n->op != Oseq)
break;
gdecl(n->left);
n = n->right;
}
switch(n->op){
case Oimport:
importdecled(n);
gdasdecl(n->right);
break;
case Oadtdecl:
adtdecled(n);
break;
case Ocondecl:
condecled(n);
gdasdecl(n->right);
break;
case Oexdecl:
exdecled(n);
break;
case Omoddecl:
moddecled(n);
break;
case Otypedecl:
typedecled(n);
break;
case Ovardecl:
vardecled(n);
break;
case Ovardecli:
vardecled(n->left);
gdasdecl(n->right);
break;
case Ofunc:
fndecled(n);
break;
case Oas:
case Odas:
case Onothing:
gdasdecl(n);
break;
default:
fatal("can't deal with %O in gdecl", n->op);
}
}
/*
* bind all global type ids,
* including those nested inside modules
* this needs to be done, since we may use such
* a type later in a nested scope, so if we bound
* the type ids then, the type could get bound
* to a nested declaration
*/
void
gbind(Node *n)
{
Decl *d, *ids;
for(;;){
if(n == nil)
return;
if(n->op != Oseq)
break;
gbind(n->left);
n = n->right;
}
switch(n->op){
case Oas:
case Ocondecl:
case Odas:
case Oexdecl:
case Ofunc:
case Oimport:
case Onothing:
case Ovardecl:
case Ovardecli:
break;
case Ofielddecl:
bindtypes(n->decl->ty);
break;
case Otypedecl:
bindtypes(n->decl->ty);
if(n->left != nil)
gbind(n->left);
break;
case Opickdecl:
gbind(n->left);
d = n->right->left->decl;
bindtypes(d->ty);
repushids(d->ty->ids);
gbind(n->right->right);
/* get new ids for undefined types; propagate outwards */
ids = popids(d->ty->ids);
if(ids != nil)
installids(Dundef, ids);
break;
case Oadtdecl:
case Omoddecl:
bindtypes(n->ty);
if(n->ty->polys != nil)
repushids(n->ty->polys);
repushids(n->ty->ids);
gbind(n->left);
/* get new ids for undefined types; propagate outwards */
ids = popids(n->ty->ids);
if(ids != nil)
installids(Dundef, ids);
if(n->ty->polys != nil)
popids(n->ty->polys);
break;
default:
fatal("can't deal with %O in gbind", n->op);
}
}
/*
* check all of the > declarations
* bind all type ids referred to within types at the global level
* record decls for defined functions
*/
int
gcheck(Node *n, Decl **fns, int nfns)
{
Ok rok;
Decl *d;
for(;;){
if(n == nil)
return nfns;
if(n->op != Oseq)
break;
nfns = gcheck(n->left, fns, nfns);
n = n->right;
}
switch(n->op){
case Ofielddecl:
if(n->decl->ty->u.eraises)
raisescheck(n->decl->ty);
break;
case Onothing:
case Opickdecl:
break;
case Otypedecl:
tcycle(n->ty);
break;
case Oadtdecl:
case Omoddecl:
if(n->ty->polys != nil)
repushids(n->ty->polys);
repushids(n->ty->ids);
if(gcheck(n->left, nil, 0))
fatal("gcheck fn decls nested in modules or adts");
if(popids(n->ty->ids) != nil)
fatal("gcheck installs new ids in a module or adt");
if(n->ty->polys != nil)
popids(n->ty->polys);
break;
case Ovardecl:
varcheck(n, 1);
break;
case Ocondecl:
concheck(n, 1);
break;
case Oexdecl:
excheck(n, 1);
break;
case Oimport:
importcheck(n, 1);
break;
case Ovardecli:
varcheck(n->left, 1);
rok = echeck(n->right, 0, 1, nil);
if(rok.ok){
if(rok.allok)
n->right = fold(n->right);
globalas(n->right->left, n->right->right, rok.allok);
}
break;
case Oas:
case Odas:
rok = echeck(n, 0, 1, nil);
if(rok.ok){
if(rok.allok)
n = fold(n);
globalas(n->left, n->right, rok.allok);
}
break;
case Ofunc:
rok = echeck(n->left, 0, 1, n);
if(rok.ok && n->ty->u.eraises)
raisescheck(n->ty);
d = nil;
if(rok.ok)
d = fnchk(n);
fns[nfns++] = d;
break;
default:
fatal("can't deal with %O in gcheck", n->op);
}
return nfns;
}
/*
* check for unused expression results
* make sure the any calculated expression has
* a destination
*/
Node*
checkused(Node *n)
{
Type *t;
Node *nn;
/*
* only nil; and nil = nil; should have type tany
*/
if(n->ty == tany){
if(n->op == Oname)
return n;
if(n->op == Oas)
return checkused(n->right);
fatal("line %L checkused %n", n->src.start, n);
}
if(n->op == Ocall && n->left->ty->kind == Tfn && n->left->ty->tof != tnone){
n = mkunary(Oused, n);
n->ty = n->left->ty;
return n;
}
if(n->op == Ocall && isfnrefty(n->left->ty)){
if(n->left->ty->tof->tof != tnone){
n = mkunary(Oused, n);
n->ty = n->left->ty;
}
return n;
}
if(isused[n->op] && (n->op != Ocall || n->left->ty->kind == Tfn))
return n;
t = n->ty;
if(t->kind == Tfn)
nerror(n, "function %V not called", n);
else if(t->kind == Tadt && t->tags != nil || t->kind == Tadtpick)
nerror(n, "expressions cannot have type %T", t);
else if(n->op == Otuple){
for(nn = n->left; nn != nil; nn = nn->right)
checkused(nn->left);
}
else
nwarn(n, "result of expression %V not used", n);
n = mkunary(Oused, n);
n->ty = n->left->ty;
return n;
}
void
fncheck(Decl *d)
{
Node *n;
Decl *adtp;
n = d->init;
if(debug['t'])
print("typecheck tree: %n\n", n);
fndecls = nil;
adtp = outerpolys(n->left);
if(n->left->op == Odot)
repushids(adtp);
if(d->ty->polys != nil)
repushids(d->ty->polys);
repushids(d->ty->ids);
labdep = 0;
labstack = allocmem(maxlabdep * sizeof *labstack);
n->right = scheck(n->right, d->ty->tof, Sother);
if(labdep != 0)
fatal("unbalanced label stack in fncheck");
free(labstack);
d->locals = appdecls(popids(d->ty->ids), fndecls);
if(d->ty->polys != nil)
popids(d->ty->polys);
if(n->left->op == Odot)
popids(adtp);
fndecls = nil;
checkrefs(d->ty->ids);
checkrefs(d->ty->polys);
checkrefs(d->locals);
checkraises(n);
d->caninline = fninline(d);
}
Node*
scheck(Node *n, Type *ret, int kind)
{
Node *left, *right, *last, *top;
Decl *d;
Sym *s;
Ok rok;
int i;
top = n;
last = nil;
for(; n != nil; n = n->right){
left = n->left;
right = n->right;
switch(n->op){
case Ovardecl:
vardecled(n);
varcheck(n, 0);
if (nested() && tmustzero(n->decl->ty))
decltozero(n);
/*
else if (inloop() && tmustzero(n->decl->ty))
decltozero(n);
*/
return top;
case Ovardecli:
vardecled(left);
varcheck(left, 0);
echeck(right, 0, 0, nil);
if (nested() && tmustzero(left->decl->ty))
decltozero(left);
return top;
case Otypedecl:
typedecled(n);
bindtypes(n->ty);
tcycle(n->ty);
return top;
case Ocondecl:
condecled(n);
concheck(n, 0);
return top;
case Oexdecl:
exdecled(n);
excheck(n, 0);
return top;
case Oimport:
importdecled(n);
importcheck(n, 0);
return top;
case Ofunc:
fatal("scheck func");
case Oscope:
pushscope(n, kind == Sother ? Sscope : kind);
if (left != nil)
fatal("Oscope has left field");
echeck(left, 0, 0, nil);
n->right = scheck(right, ret, Sother);
d = popscope();
fndecls = appdecls(fndecls, d);
return top;
case Olabel:
echeck(left, 0, 0, nil);
n->right = scheck(right, ret, Sother);
return top;
case Oseq:
n->left = scheck(left, ret, Sother);
/* next time will check n->right */
break;
case Oif:
rok = echeck(left, 0, 0, nil);
if(rok.ok && left->op != Onothing && left->ty != tint)
nerror(n, "if conditional must be an int, not %Q", left);
right->left = scheck(right->left, ret, Sother);
/* next time will check n->right->right */
n = right;
break;
case Ofor:
rok = echeck(left, 0, 0, nil);
if(rok.ok && left->op != Onothing && left->ty != tint)
nerror(n, "for conditional must be an int, not %Q", left);
/*
* do the continue clause before the body
* this reflects the ordering of declarations
*/
pushlabel(n);
right->right = scheck(right->right, ret, Sother);
right->left = scheck(right->left, ret, Sloop);
labdep--;
if(n->decl != nil && !n->decl->refs)
nwarn(n, "label %s never referenced", n->decl->sym->name);
return top;
case Odo:
rok = echeck(left, 0, 0, nil);
if(rok.ok && left->op != Onothing && left->ty != tint)
nerror(n, "do conditional must be an int, not %Q", left);
pushlabel(n);
n->right = scheck(n->right, ret, Sloop);
labdep--;
if(n->decl != nil && !n->decl->refs)
nwarn(n, "label %s never referenced", n->decl->sym->name);
return top;
case Oalt:
case Ocase:
case Opick:
case Oexcept:
pushlabel(n);
switch(n->op){
case Oalt:
altcheck(n, ret);
break;
case Ocase:
casecheck(n, ret);
break;
case Opick:
pickcheck(n, ret);
break;
case Oexcept:
exccheck(n, ret);
break;
}
labdep--;
if(n->decl != nil && !n->decl->refs)
nwarn(n, "label %s never referenced", n->decl->sym->name);
return top;
case Oret:
rok = echeck(left, 0, 0, nil);
if(!rok.ok)
return top;
if(left == nil){
if(ret != tnone)
nerror(n, "return of nothing from a fn of %T", ret);
}else if(ret == tnone){
if(left->ty != tnone)
nerror(n, "return %Q from a fn with no return type", left);
}else if(!tcompat(ret, left->ty, 0))
nerror(n, "return %Q from a fn of %T", left, ret);
return top;
case Obreak:
case Ocont:
s = nil;
if(n->decl != nil)
s = n->decl->sym;
for(i = 0; i < labdep; i++){
if(s == nil || labstack[i]->decl != nil && labstack[i]->decl->sym == s){
if(n->op == Ocont
&& labstack[i]->op != Ofor && labstack[i]->op != Odo)
continue;
if(s != nil)
labstack[i]->decl->refs++;
return top;
}
}
nerror(n, "no appropriate target for %V", n);
return top;
case Oexit:
case Onothing:
return top;
case Oexstmt:
fndec->handler = 1;
n->left = scheck(left, ret, Sother);
n->right = scheck(right, ret, Sother);
return top;
default:
rok = echeck(n, 0, 0, nil);
if(rok.allok)
n = checkused(n);
if(last == nil)
return n;
last->right = n;
return top;
}
last = n;
}
return top;
}
void
pushlabel(Node *n)
{
Sym *s;
int i;
if(labdep >= maxlabdep){
maxlabdep += MaxScope;
labstack = reallocmem(labstack, maxlabdep * sizeof *labstack);
}
if(n->decl != nil){
s = n->decl->sym;
n->decl->refs = 0;
for(i = 0; i < labdep; i++)
if(labstack[i]->decl != nil && labstack[i]->decl->sym == s)
nerror(n, "label %s duplicated on line %L", s->name, labstack[i]->decl->src.start);
}
labstack[labdep++] = n;
}
void
varcheck(Node *n, int isglobal)
{
Type *t;
Decl *ids, *last;
t = validtype(n->ty, nil);
t = topvartype(t, n->decl, isglobal, 0);
last = n->left->decl;
for(ids = n->decl; ids != last->next; ids = ids->next){
ids->ty = t;
shareloc(ids);
}
if(t->u.eraises)
raisescheck(t);
}
void
concheck(Node *n, int isglobal)
{
Decl *ids, *last;
Type *t;
Node *init;
Ok rok;
int i;
pushscope(nil, Sother);
installids(Dconst, iota);
rok = echeck(n->right, 0, isglobal, nil);
popscope();
init = n->right;
if(!rok.ok){
t = terror;
}else{
t = init->ty;
if(!tattr[t->kind].conable){
nerror(init, "cannot have a %T constant", t);
rok.allok = 0;
}
}
last = n->left->decl;
for(ids = n->decl; ids != last->next; ids = ids->next)
ids->ty = t;
if(!rok.allok)
return;
i = 0;
for(ids = n->decl; ids != last->next; ids = ids->next){
if(rok.ok){
iota->init->val = i;
ids->init = dupn(0, &nosrc, init);
if(!varcom(ids))
rok.ok = 0;
}
i++;
}
}
static char*
exname(Decl *d)
{
int n;
Sym *m;
char *s;
char buf[16];
n = 0;
sprint(buf, "%d", scope-ScopeGlobal);
m = nil;
if(d->dot)
m = d->dot->sym;
else if(impmods)
m = impmods->sym;
if(m)
n += strlen(m->name)+1;
if(fndec)
n += strlen(fndec->sym->name)+1;
n += strlen(buf)+1+strlen(d->sym->name)+1;
s = malloc(n);
strcpy(s, "");
if(m){
strcat(s, m->name);
strcat(s, ".");
}
if(fndec){
strcat(s, fndec->sym->name);
strcat(s, ".");
}
strcat(s, buf);
strcat(s, ".");
strcat(s, d->sym->name);
return s;
}
void
excheck(Node *n, int isglobal)
{
char *nm;
Type *t;
Decl *ids, *last;
t = validtype(n->ty, nil);
t = topvartype(t, n->decl, isglobal, 0);
last = n->left->decl;
for(ids = n->decl; ids != last->next; ids = ids->next){
ids->ty = t;
nm = exname(ids);
ids->init = mksconst(&n->src, enterstring(nm, strlen(nm)));
/* ids->init = mksconst(&n->src, enterstring(strdup(ids->sym->name), strlen(ids->sym->name))); */
}
}
void
importcheck(Node *n, int isglobal)
{
Node *m;
Decl *id, *last, *v;
Type *t;
Ok rok;
rok = echeck(n->right, 1, isglobal, nil);
if(!rok.ok)
return;
m = n->right;
if(m->ty->kind != Tmodule || m->op != Oname){
nerror(n, "cannot import from %Q", m);
return;
}
last = n->left->decl;
for(id = n->decl; id != last->next; id = id->next){
v = namedot(m->ty->ids, id->sym);
if(v == nil){
error(id->src.start, "%s is not a member of %V", id->sym->name, m);
id->store = Dwundef;
continue;
}
id->store = v->store;
v->ty = validtype(v->ty, nil);
id->ty = t = v->ty;
if(id->store == Dtype && t->decl != nil){
id->timport = t->decl->timport;
t->decl->timport = id;
}
id->init = v->init;
id->importid = v;
id->eimport = m;
}
}
static Decl*
rewcall(Node *n, Decl *d)
{
/* put original function back now we're type checked */
while(d->link != nil)
d = d->link;
if(n->op == Odot)
n->right->decl = d;
else if(n->op == Omdot){
n->right->right->decl = d;
n->right->right->ty = d->ty;
}
else
fatal("bad op in Ocall rewcall");
n->ty = n->right->ty = d->ty;
d->refs++;
usetype(d->ty);
return d;
}
/*
* annotate the expression with types
*/
Ok
echeck(Node *n, int typeok, int isglobal, Node *par)
{
Type *t, *tt;
Node *left, *right, *mod, *nn;
Decl *tg, *id, *callee;
Sym *s;
int max, nocheck;
Ok ok, rok, kidsok;
static int tagopt;
ok.ok = ok.allok = 1;
if(n == nil)
return ok;
/* avoid deep recursions */
if(n->op == Oseq){
for( ; n != nil && n->op == Oseq; n = n->right){
rok = echeck(n->left, typeok == 2, isglobal, n);
ok.ok &= rok.ok;
ok.allok &= rok.allok;
n->ty = tnone;
}
if(n == nil)
return ok;
}
left = n->left;
right = n->right;
nocheck = 0;
if(n->op == Odot || n->op == Omdot || n->op == Ocall || n->op == Oref || n->op == Otagof || n->op == Oindex)
nocheck = 1;
if(n->op != Odas /* special case */
&& n->op != Oload) /* can have better error recovery */
ok = echeck(left, nocheck, isglobal, n);
if(n->op != Odas /* special case */
&& n->op != Odot /* special check */
&& n->op != Omdot /* special check */
&& n->op != Ocall /* can have better error recovery */
&& n->op != Oindex){
rok = echeck(right, 0, isglobal, n);
ok.ok &= rok.ok;
ok.allok &= rok.allok;
}
if(!ok.ok){
n->ty = terror;
ok.allok = 0;
return ok;
}
switch(n->op){
case Odas:
kidsok = echeck(right, 0, isglobal, n);
if(!kidsok.ok)
right->ty = terror;
if(!isglobal && !dasdecl(left)){
kidsok.ok = 0;
}else if(!specific(right->ty) || !declasinfer(left, right->ty)){
nerror(n, "cannot declare %V from %Q", left, right);
declaserr(left);
kidsok.ok = 0;
}
if(right->ty->kind == Texception)
left->ty = n->ty = mkextuptype(right->ty);
else{
left->ty = n->ty = right->ty;
usedty(n->ty);
}
kidsok.allok &= kidsok.ok;
if (nested() && tmustzero(left->ty))
decltozero(left);
return kidsok;
case Oseq:
case Onothing:
n->ty = tnone;
break;
case Owild:
n->ty = tint;
break;
case Ocast:
t = usetype(n->ty);
n->ty = t;
tt = left->ty;
if(tcompat(t, tt, 0)){
left->ty = t;
break;
}
if(tt->kind == Tarray){
if(tt->tof == tbyte && t == tstring)
break;
}else if(t->kind == Tarray){
if(t->tof == tbyte && tt == tstring)
break;
}else if(casttab[tt->kind][t->kind]){
break;
}
nerror(n, "cannot make a %T from %Q", n->ty, left);
ok.ok = ok.allok = 0;
return ok;
case Ochan:
n->ty = usetype(n->ty);
if(left && left->ty->kind != Tint){
nerror(n, "channel size %Q is not an int", left);
ok.ok = ok.allok = 0;
return ok;
}
break;
case Oload:
n->ty = usetype(n->ty);
kidsok = echeck(left, 0, isglobal, n);
if(n->ty->kind != Tmodule){
nerror(n, "cannot load a %T, ", n->ty);
ok.ok = ok.allok = 0;
return ok;
}
if(!kidsok.allok){
ok.allok = 0;
break;
}
if(left->ty != tstring){
nerror(n, "cannot load a module from %Q", left);
ok.allok = 0;
break;
}
if(n->ty->tof->decl->refs != 0)
n->ty->tof->decl->refs++;
n->ty->decl->refs++;
usetype(n->ty->tof);
break;
case Oref:
t = left->ty;
if(t->kind != Tadt && t->kind != Tadtpick && t->kind != Tfn && t->kind != Ttuple){
nerror(n, "cannot make a ref from %Q", left);
ok.ok = ok.allok = 0;
return ok;
}
if(!tagopt && t->kind == Tadt && t->tags != nil && valistype(left)){
nerror(n, "instances of ref %V must be qualified with a pick tag", left);
ok.ok = ok.allok = 0;
return ok;
}
if(t->kind == Tadtpick)
t->tof = usetype(t->tof);
n->ty = usetype(mktype(&n->src.start, &n->src.stop, Tref, t, nil));
break;
case Oarray:
max = 0;
if(right != nil){
max = assignindices(n);
if(max < 0){
ok.ok = ok.allok = 0;
return ok;
}
if(!specific(right->left->ty)){
nerror(n, "type for array not specific");
ok.ok = ok.allok = 0;
return ok;
}
n->ty = mktype(&n->src.start, &n->src.stop, Tarray, right->left->ty, nil);
}
n->ty = usetype(n->ty);
if(left->op == Onothing)
n->left = left = mkconst(&n->left->src, max);
if(left->ty->kind != Tint){
nerror(n, "array size %Q is not an int", left);
ok.ok = ok.allok = 0;
return ok;
}
break;
case Oelem:
n->ty = right->ty;
break;
case Orange:
if(left->ty != right->ty
|| left->ty != tint && left->ty != tstring){
nerror(left, "range %Q to %Q is not an int or string range", left, right);
ok.ok = ok.allok = 0;
return ok;
}
n->ty = left->ty;
break;
case Oname:
id = n->decl;
if(id == nil){
nerror(n, "name with no declaration");
ok.ok = ok.allok = 0;
return ok;
}
if(id->store == Dunbound){
s = id->sym;
id = s->decl;
if(id == nil)
id = undefed(&n->src, s);
/* save a little space */
s->unbound = nil;
n->decl = id;
id->refs++;
}
n->ty = id->ty = usetype(id->ty);
switch(id->store){
case Dfn:
case Dglobal:
case Darg:
case Dlocal:
case Dimport:
case Dfield:
case Dtag:
break;
case Dundef:
nerror(n, "%s is not declared", id->sym->name);
id->store = Dwundef;
ok.ok = ok.allok = 0;
return ok;
case Dwundef:
ok.ok = ok.allok = 0;
return ok;
case Dconst:
if(id->init == nil){
nerror(n, "%s's value cannot be determined", id->sym->name);
id->store = Dwundef;
ok.ok = ok.allok = 0;
return ok;
}
break;
case Dtype:
if(typeok)
break;
nerror(n, "%K is not a variable", id);
ok.ok = ok.allok = 0;
return ok;
default:
fatal("echeck: unknown symbol storage");
}
if(n->ty == nil){
nerror(n, "%K's type is not fully defined", id);
id->store = Dwundef;
ok.ok = ok.allok = 0;
return ok;
}
if(id->importid != nil && valistype(id->eimport)
&& id->store != Dconst && id->store != Dtype && id->store != Dfn){
nerror(n, "cannot use %V because %V is a module interface", n, id->eimport);
ok.ok = ok.allok = 0;
return ok;
}
if(n->ty->kind == Texception && !n->ty->cons && par != nil && par->op != Oraise && par->op != Odot){
nn = mkn(0, nil, nil);
*nn = *n;
n->op = Ocast;
n->left = nn;
n->decl = nil;
n->ty = usetype(mkextuptype(n->ty));
}
/* function name as function reference */
if(id->store == Dfn && (par == nil || (par->op != Odot && par->op != Omdot && par->op != Ocall && par->op != Ofunc)))
fnref(n, id);
break;
case Oconst:
if(n->ty == nil){
nerror(n, "no type in %V", n);
ok.ok = ok.allok = 0;
return ok;
}
break;
case Oas:
t = right->ty;
if(t->kind == Texception)
t = mkextuptype(t);
if(!tcompat(left->ty, t, 1)){
nerror(n, "type clash in %Q = %Q", left, right);
ok.ok = ok.allok = 0;
return ok;
}
if(t == tany)
t = left->ty;
n->ty = t;
left->ty = t;
if(t->kind == Tadt && t->tags != nil || t->kind == Tadtpick)
if(left->ty->kind != Tadtpick || right->ty->kind != Tadtpick)
nerror(n, "expressions cannot have type %T", t);
if(left->ty->kind == Texception){
nerror(n, "cannot assign to an exception");
ok.ok = ok.allok = 0;
return ok;
}
if(islval(left))
break;
ok.ok = ok.allok = 0;
return ok;
case Osnd:
if(left->ty->kind != Tchan){
nerror(n, "cannot send on %Q", left);
ok.ok = ok.allok = 0;
return ok;
}
if(!tcompat(left->ty->tof, right->ty, 0)){
nerror(n, "type clash in %Q <-= %Q", left, right);
ok.ok = ok.allok = 0;
return ok;
}
t = right->ty;
if(t == tany)
t = left->ty->tof;
n->ty = t;
break;
case Orcv:
t = left->ty;
if(t->kind == Tarray)
t = t->tof;
if(t->kind != Tchan){
nerror(n, "cannot receive on %Q", left);
ok.ok = ok.allok = 0;
return ok;
}
if(left->ty->kind == Tarray)
n->ty = usetype(mktype(&n->src.start, &n->src.stop, Ttuple, nil,
mkids(&n->src, nil, tint, mkids(&n->src, nil, t->tof, nil))));
else
n->ty = t->tof;
break;
case Ocons:
if(right->ty->kind != Tlist && right->ty != tany){
nerror(n, "cannot :: to %Q", right);
ok.ok = ok.allok = 0;
return ok;
}
n->ty = right->ty;
if(right->ty == tany)
n->ty = usetype(mktype(&n->src.start, &n->src.stop, Tlist, left->ty, nil));
else if(!tcompat(right->ty->tof, left->ty, 0)){
t = tparent(right->ty->tof, left->ty);
if(!tcompat(t, left->ty, 0)){
nerror(n, "type clash in %Q :: %Q", left, right);
ok.ok = ok.allok = 0;
return ok;
}
else
n->ty = usetype(mktype(&n->src.start, &n->src.stop, Tlist, t, nil));
}
break;
case Ohd:
case Otl:
if(left->ty->kind != Tlist || left->ty->tof == nil){
nerror(n, "cannot %O %Q", n->op, left);
ok.ok = ok.allok = 0;
return ok;
}
if(n->op == Ohd)
n->ty = left->ty->tof;
else
n->ty = left->ty;
break;
case Otuple:
n->ty = usetype(mktype(&n->src.start, &n->src.stop, Ttuple, nil, tuplefields(left)));
break;
case Ospawn:
if(left->op != Ocall || left->left->ty->kind != Tfn && !isfnrefty(left->left->ty)){
nerror(left, "cannot spawn %V", left);
ok.ok = ok.allok = 0;
return ok;
}
if(left->ty != tnone){
nerror(left, "cannot spawn functions which return values, such as %Q", left);
ok.ok = ok.allok = 0;
return ok;
}
break;
case Oraise:
if(left->op == Onothing){
if(inexcept == nil){
nerror(n, "%V: empty raise not in exception handler", n);
ok.ok = ok.allok = 0;
return ok;
}
n->left = dupn(1, &n->src, inexcept);
break;
}
if(left->ty != tstring && left->ty->kind != Texception){
nerror(n, "%V: raise argument %Q is not a string or exception", n, left);
ok.ok = ok.allok = 0;
return ok;
}
if((left->op != Ocall || left->left->ty->kind == Tfn) && left->ty->ids != nil && left->ty->cons){
nerror(n, "too few exception arguments");
ok.ok = ok.allok = 0;
return ok;
}
break;
case Ocall:{
int pure;
kidsok = echeck(right, 0, isglobal, nil);
t = left->ty;
usedty(t);
pure = 1;
if(t->kind == Tref){
pure = 0;
t = t->tof;
}
if(t->kind != Tfn)
return callcast(n, kidsok.allok, ok.allok);
n->ty = t->tof;
if(!kidsok.allok){
ok.allok = 0;
break;
}
/*
* get the name to call and any associated module
*/
mod = nil;
callee = nil;
id = nil;
tt = nil;
if(left->op == Odot){
Decl *dd;
Type *ttt;
callee = left->right->decl;
id = callee->dot;
right = passimplicit(left, right);
n->right = right;
tt = left->left->ty;
if(tt->kind == Tref)
tt = tt->tof;
ttt = tt;
if(tt->kind == Tadtpick)
ttt = tt->decl->dot->ty;
dd = ttt->decl;
while(dd != nil && dd->link != nil)
dd = dd->link;
if(dd != nil && dd->timport != nil)
mod = dd->timport->eimport;
/*
* stash the import module under a rock,
* because we won't be able to get it later
* after scopes are popped
*/
left->right->left = mod;
}else if(left->op == Omdot){
if(left->right->op == Odot){
callee = left->right->right->decl;
right = passimplicit(left->right, right);
n->right = right;
tt = left->right->left->ty;
if(tt->kind == Tref)
tt = tt->tof;
}else
callee = left->right->decl;
mod = left->left;
}else if(left->op == Oname){
callee = left->decl;
id = callee;
mod = id->eimport;
}else if(pure){
nerror(left, "%V is not a function name", left);
ok.allok = 0;
break;
}
if(pure && callee == nil)
fatal("can't find called function: %n", left);
if(callee != nil && callee->store != Dfn && !isfnref(callee)){
nerror(left, "%V is not a function or function reference", left);
ok.allok = 0;
break;
}
if(mod != nil && mod->ty->kind != Tmodule){
nerror(left, "cannot call %V", left);
ok.allok = 0;
break;
}
if(mod != nil){
if(valistype(mod)){
nerror(left, "cannot call %V because %V is a module interface", left, mod);
ok.allok = 0;
break;
}
}else if(id != nil && id->dot != nil && !isimpmod(id->dot->sym)){
nerror(left, "cannot call %V without importing %s from a variable", left, id->sym->name);
ok.allok = 0;
break;
}
if(mod != nil)
modrefable(left->ty);
if(callee != nil && callee->store != Dfn)
callee = nil;
if(t->varargs != 0){
t = mkvarargs(left, right);
if(left->ty->kind == Tref)
left->ty = usetype(mktype(&t->src.start, &t->src.stop, Tref, t, nil));
else
left->ty = t;
}
else if(ispoly(callee) || isfnrefty(left->ty) && left->ty->tof->polys != nil){
Tpair *tp;
unifysrc = n->src;
if(!argncompat(n, t->ids, right))
ok.allok = 0;
else if(!tunify(left->ty, calltype(left->ty, right, n->ty), &tp)){
nerror(n, "function call type mismatch");
ok.allok = 0;
}
else{
n->ty = usetype(expandtype(n->ty, nil, nil, &tp));
if(ispoly(callee) && tt != nil && (tt->kind == Tadt || tt->kind == Tadtpick) && (tt->flags&INST))
callee = rewcall(left, callee);
n->right = passfns(&n->src, callee, left, right, tt, tp);
}
}
else if(!argcompat(n, t->ids, right))
ok.allok = 0;
break;
}
case Odot:
t = left->ty;
if(t->kind == Tref)
t = t->tof;
switch(t->kind){
case Tadt:
case Tadtpick:
case Ttuple:
case Texception:
case Tpoly:
id = namedot(t->ids, right->decl->sym);
if(id == nil){
id = namedot(t->tags, right->decl->sym);
if(id != nil && !valistype(left)){
nerror(n, "%V is not a type", left);
ok.ok = ok.allok = 0;
return ok;
}
}
if(id == nil){
id = namedot(t->polys, right->decl->sym);
if(id != nil && !valistype(left)){
nerror(n, "%V is not a type", left);
ok.ok = ok.allok = 0;
return ok;
}
}
if(id == nil && t->kind == Tadtpick)
id = namedot(t->decl->dot->ty->ids, right->decl->sym);
if(id == nil){
for(tg = t->tags; tg != nil; tg = tg->next){
id = namedot(tg->ty->ids, right->decl->sym);
if(id != nil)
break;
}
if(id != nil){
nerror(n, "cannot yet index field %s of %Q", right->decl->sym->name, left);
ok.ok = ok.allok = 0;
return ok;
}
}
if(id == nil)
break;
if(id->store == Dfield && valistype(left)){
nerror(n, "%V is not a value", left);
ok.ok = ok.allok = 0;
return ok;
}
id->ty = validtype(id->ty, t->decl);
id->ty = usetype(id->ty);
break;
default:
nerror(left, "%Q cannot be qualified with .", left);
ok.ok = ok.allok = 0;
return ok;
}
if(id == nil){
nerror(n, "%V is not a member of %Q", right, left);
ok.ok = ok.allok = 0;
return ok;
}
if(id->ty == tunknown){
nerror(n, "illegal forward reference to %V", n);
ok.ok = ok.allok = 0;
return ok;
}
increfs(id);
right->decl = id;
n->ty = id->ty;
if((id->store == Dconst || id->store == Dtag) && hasside(left, 1))
nwarn(left, "result of expression %Q ignored", left);
/* function name as function reference */
if(id->store == Dfn && (par == nil || (par->op != Omdot && par->op != Ocall && par->op != Ofunc)))
fnref(n, id);
break;
case Omdot:
t = left->ty;
if(t->kind != Tmodule){
nerror(left, "%Q cannot be qualified with ->", left);
ok.ok = ok.allok = 0;
return ok;
}
id = nil;
if(right->op == Oname){
id = namedot(t->ids, right->decl->sym);
}else if(right->op == Odot){
kidsok = echeck(right, 0, isglobal, n);
ok.ok = kidsok.ok;
ok.allok &= kidsok.allok;
if(!ok.ok){
ok.allok = 0;
return ok;
}
tt = right->left->ty;
if(tt->kind == Tref)
tt = tt->tof;
if(right->ty->kind == Tfn
&& tt->kind == Tadt
&& tt->decl->dot == t->decl)
id = right->right->decl;
}
if(id == nil){
nerror(n, "%V is not a member of %Q", right, left);
ok.ok = ok.allok = 0;
return ok;
}
if(id->store != Dconst && id->store != Dtype && id->store != Dtag){
if(valistype(left)){
nerror(n, "%V is not a value", left);
ok.ok = ok.allok = 0;
return ok;
}
}else if(hasside(left, 1))
nwarn(left, "result of expression %Q ignored", left);
if(!typeok && id->store == Dtype){
nerror(n, "%V is a type, not a value", n);
ok.ok = ok.allok = 0;
return ok;
}
if(id->ty == tunknown){
nerror(n, "illegal forward reference to %V", n);
ok.ok = ok.allok = 0;
return ok;
}
id->refs++;
right->decl = id;
n->ty = id->ty = usetype(id->ty);
if(id->store == Dglobal)
modrefable(id->ty);
/* function name as function reference */
if(id->store == Dfn && (par == nil || (par->op != Ocall && par->op != Ofunc)))
fnref(n, id);
break;
case Otagof:
n->ty = tint;
t = left->ty;
if(t->kind == Tref)
t = t->tof;
id = nil;
switch(left->op){
case Oname:
id = left->decl;
break;
case Odot:
id = left->right->decl;
break;
case Omdot:
if(left->right->op == Odot)
id = left->right->right->decl;
break;
}
if(id != nil && id->store == Dtag
|| id != nil && id->store == Dtype && t->kind == Tadt && t->tags != nil)
n->decl = id;
else if(t->kind == Tadt && t->tags != nil || t->kind == Tadtpick)
n->decl = nil;
else{
nerror(n, "cannot get the tag value for %Q", left);
ok.ok = 1;
ok.allok = 0;
return ok;
}
break;
case Oind:
t = left->ty;
if(t->kind != Tref || (t->tof->kind != Tadt && t->tof->kind != Tadtpick && t->tof->kind != Ttuple)){
nerror(n, "cannot * %Q", left);
ok.ok = ok.allok = 0;
return ok;
}
n->ty = t->tof;
for(tg = t->tof->tags; tg != nil; tg = tg->next)
tg->ty->tof = usetype(tg->ty->tof);
break;
case Oindex:
if(valistype(left)){
tagopt = 1;
kidsok = echeck(right, 2, isglobal, n);
tagopt = 0;
if(!kidsok.allok){
ok.ok = ok.allok = 0;
return ok;
}
if((t = exptotype(n)) == nil){
nerror(n, "%V is not a type list", right);
ok.ok = ok.allok = 0;
return ok;
}
if(!typeok){
nerror(n, "%Q is not a variable", left);
ok.ok = ok.allok = 0;
return ok;
}
*n = *(n->left);
n->ty = usetype(t);
break;
}
if(0 && right->op == Oseq){ /* a[e1, e2, ...] */
/* array creation to do before we allow this */
rewind(n);
return echeck(n, typeok, isglobal, par);
}
t = left->ty;
kidsok = echeck(right, 0, isglobal, n);
if(t->kind != Tarray && t != tstring){
nerror(n, "cannot index %Q", left);
ok.ok = ok.allok = 0;
return ok;
}
if(t == tstring){
n->op = Oinds;
n->ty = tint;
}else{
n->ty = t->tof;
}
if(!kidsok.allok){
ok.allok = 0;
break;
}
if(right->ty != tint){
nerror(n, "cannot index %Q with %Q", left, right);
ok.allok = 0;
break;
}
break;
case Oslice:
t = n->ty = left->ty;
if(t->kind != Tarray && t != tstring){
nerror(n, "cannot slice %Q with '%v:%v'", left, right->left, right->right);
ok.ok = ok.allok = 0;
return ok;
}
if(right->left->ty != tint && right->left->op != Onothing
|| right->right->ty != tint && right->right->op != Onothing){
nerror(n, "cannot slice %Q with '%v:%v'", left, right->left, right->right);
ok.allok = 0;
return ok;
}
break;
case Olen:
t = left->ty;
n->ty = tint;
if(t->kind != Tarray && t->kind != Tlist && t != tstring){
nerror(n, "len requires an array, string or list in %Q", left);
ok.allok = 0;
return ok;
}
break;
case Ocomp:
case Onot:
case Oneg:
n->ty = left->ty;
usedty(n->ty);
switch(left->ty->kind){
case Tint:
return ok;
case Treal:
case Tfix:
if(n->op == Oneg)
return ok;
break;
case Tbig:
case Tbyte:
if(n->op == Oneg || n->op == Ocomp)
return ok;
break;
}
nerror(n, "cannot apply %O to %Q", n->op, left);
ok.ok = ok.allok = 0;
return ok;
case Oinc:
case Odec:
case Opreinc:
case Opredec:
n->ty = left->ty;
switch(left->ty->kind){
case Tint:
case Tbig:
case Tbyte:
case Treal:
break;
default:
nerror(n, "cannot apply %O to %Q", n->op, left);
ok.ok = ok.allok = 0;
return ok;
}
if(islval(left))
break;
ok.ok = ok.allok = 0;
return ok;
case Oadd:
case Odiv:
case Omul:
case Osub:
if(mathchk(n, 1))
break;
ok.ok = ok.allok = 0;
return ok;
case Oexp:
case Oexpas:
n->ty = left->ty;
if(n->ty != tint && n->ty != tbig && n->ty != treal){
nerror(n, "exponend %Q is not int, big or real", left);
ok.ok = ok.allok = 0;
return ok;
}
if(right->ty != tint){
nerror(n, "exponent %Q is not int", right);
ok.ok = ok.allok = 0;
return ok;
}
if(n->op == Oexpas && !islval(left)){
ok.ok = ok.allok = 0;
return ok;
}
break;
case Olsh:
case Orsh:
if(shiftchk(n))
break;
ok.ok = ok.allok = 0;
return ok;
case Oandand:
case Ooror:
if(left->ty != tint){
nerror(n, "%O's left operand is not an int: %Q", n->op, left);
ok.allok = 0;
}
if(right->ty != tint){
nerror(n, "%O's right operand is not an int: %Q", n->op, right);
ok.allok = 0;
}
n->ty = tint;
break;
case Oand:
case Omod:
case Oor:
case Oxor:
if(mathchk(n, 0))
break;
ok.ok = ok.allok = 0;
return ok;
case Oaddas:
case Odivas:
case Omulas:
case Osubas:
if(mathchk(n, 1) && islval(left))
break;
ok.ok = ok.allok = 0;
return ok;
case Olshas:
case Orshas:
if(shiftchk(n) && islval(left))
break;
ok.ok = ok.allok = 0;
return ok;
case Oandas:
case Omodas:
case Oxoras:
case Ooras:
if(mathchk(n, 0) && islval(left))
break;
ok.ok = ok.allok = 0;
return ok;
case Olt:
case Oleq:
case Ogt:
case Ogeq:
if(!mathchk(n, 1)){
ok.ok = ok.allok = 0;
return ok;
}
n->ty = tint;
break;
case Oeq:
case Oneq:
switch(left->ty->kind){
case Tint:
case Tbig:
case Tbyte:
case Treal:
case Tstring:
case Tref:
case Tlist:
case Tarray:
case Tchan:
case Tany:
case Tmodule:
case Tfix:
case Tpoly:
if(!tcompat(left->ty, right->ty, 0) && !tcompat(right->ty, left->ty, 0))
break;
t = left->ty;
if(t == tany)
t = right->ty;
if(t == tany)
t = tint;
if(left->ty == tany)
left->ty = t;
if(right->ty == tany)
right->ty = t;
n->ty = tint;
return ok;
}
nerror(n, "cannot compare %Q to %Q", left, right);
usedty(n->ty);
ok.ok = ok.allok = 0;
return ok;
case Otype:
if(!typeok){
nerror(n, "%Q is not a variable", n);
ok.ok = ok.allok = 0;
return ok;
}
n->ty = usetype(n->ty);
break;
default:
fatal("unknown op in typecheck: %O", n->op);
}
usedty(n->ty);
return ok;
}
/*
* n is syntactically a call, but n->left is not a fn
* check if it's the contructor for an adt
*/
Ok
callcast(Node *n, int kidsok, int allok)
{
Node *left, *right;
Decl *id;
Type *t, *tt;
Ok ok;
left = n->left;
right = n->right;
id = nil;
switch(left->op){
case Oname:
id = left->decl;
break;
case Omdot:
if(left->right->op == Odot)
id = left->right->right->decl;
else
id = left->right->decl;
break;
case Odot:
id = left->right->decl;
break;
}
/*
(chan of int)(nil) looks awkward since both sets of brackets needed
if(id == nil && right != nil && right->right == nil && (t = exptotype(left)) != nil){
n->op = Ocast;
n->left = right->left;
n->right = nil;
n->ty = t;
return echeck(n, 0, 0, nil);
}
*/
if(id == nil || (id->store != Dtype && id->store != Dtag && id->ty->kind != Texception)){
nerror(left, "%V is not a function or type name", left);
ok.ok = ok.allok = 0;
return ok;
}
if(id->store == Dtag)
return tagcast(n, left, right, id, kidsok, allok);
t = left->ty;
n->ty = t;
if(!kidsok){
ok.ok = 1;
ok.allok = 0;
return ok;
}
if(t->kind == Tref)
t = t->tof;
tt = mktype(&n->src.start, &n->src.stop, Ttuple, nil, tuplefields(right));
if(t->kind == Tadt && tcompat(t, tt, 1)){
if(right == nil)
*n = *n->left;
ok.ok = 1;
ok.allok = allok;
return ok;
}
/* try an exception with args */
tt = mktype(&n->src.start, &n->src.stop, Texception, nil, tuplefields(right));
tt->cons = 1;
if(t->kind == Texception && t->cons && tcompat(t, tt, 1)){
if(right == nil)
*n = *n->left;
ok.ok = 1;
ok.allok = allok;
return ok;
}
/* try a cast */
if(t->kind != Texception && right != nil && right->right == nil){ /* Oseq but single expression */
right = right->left;
n->op = Ocast;
n->left = right;
n->right = nil;
n->ty = mkidtype(&n->src, id->sym);
return echeck(n, 0, 0, nil);
}
nerror(left, "cannot make a %V from '(%v)'", left, right);
ok.ok = ok.allok = 0;
return ok;
}
Ok
tagcast(Node *n, Node *left, Node *right, Decl *id, int kidsok, int allok)
{
Type *tt;
Ok ok;
left->ty = id->ty;
if(left->op == Omdot)
left->right->ty = id->ty;
n->ty = id->ty;
if(!kidsok){
ok.ok = 1;
ok.allok = 0;
return ok;
}
id->ty->tof = usetype(id->ty->tof);
if(right != nil)
right->ty = id->ty->tof;
tt = mktype(&n->src.start, &n->src.stop, Ttuple, nil, mkids(&nosrc, nil, tint, tuplefields(right)));
tt->ids->store = Dfield;
if(tcompat(id->ty->tof, tt, 1)){
ok.ok = 1;
ok.allok = allok;
return ok;
}
nerror(left, "cannot make a %V from '(%v)'", left, right);
ok.ok = ok.allok = 0;
return ok;
}
int
valistype(Node *n)
{
switch(n->op){
case Oname:
if(n->decl->store == Dtype)
return 1;
break;
case Omdot:
return valistype(n->right);
}
return 0;
}
int
islval(Node *n)
{
int s;
s = marklval(n);
if(s == 1)
return 1;
if(s == 0)
nerror(n, "cannot assign to %V", n);
else
circlval(n, n);
return 0;
}
/*
* check to see if n is an lval
* mark the lval name as set
*/
int
marklval(Node *n)
{
Decl *id;
Node *nn;
int s;
if(n == nil)
return 0;
switch(n->op){
case Oname:
return storespace[n->decl->store] && n->ty->kind != Texception; /*ZZZZ && n->decl->tagged == nil;*/
case Odot:
if(n->right->decl->store != Dfield)
return 0;
if(n->right->decl->cycle && !n->right->decl->cyc)
return -1;
if(n->left->ty->kind != Tref && marklval(n->left) == 0)
nwarn(n, "assignment to %Q ignored", n);
return 1;
case Omdot:
if(n->right->decl->store == Dglobal)
return 1;
return 0;
case Oind:
for(id = n->ty->ids; id != nil; id = id->next)
if(id->cycle && !id->cyc)
return -1;
return 1;
case Oslice:
if(n->right->right->op != Onothing || n->ty == tstring)
return 0;
return 1;
case Oinds:
/*
* make sure we don't change a string constant
*/
switch(n->left->op){
case Oconst:
return 0;
case Oname:
return storespace[n->left->decl->store];
case Odot:
case Omdot:
if(n->left->right->decl != nil)
return storespace[n->left->right->decl->store];
break;
}
return 1;
case Oindex:
case Oindx:
return 1;
case Otuple:
for(nn = n->left; nn != nil; nn = nn->right){
s = marklval(nn->left);
if(s != 1)
return s;
}
return 1;
default:
return 0;
}
}
/*
* n has a circular field assignment.
* find it and print an error message.
*/
int
circlval(Node *n, Node *lval)
{
Decl *id;
Node *nn;
int s;
if(n == nil)
return 0;
switch(n->op){
case Oname:
break;
case Odot:
if(oldcycles && n->right->decl->cycle && !n->right->decl->cyc){
nerror(lval, "cannot assign to %V because field '%s' of %V could complete a cycle to %V",
lval, n->right->decl->sym->name, n->left, n->left);
return -1;
}
return 1;
case Oind:
if(!oldcycles)
return 1;
for(id = n->ty->ids; id != nil; id = id->next){
if(id->cycle && !id->cyc){
nerror(lval, "cannot assign to %V because field '%s' of %V could complete a cycle to %V",
lval, id->sym->name, n, n);
return -1;
}
}
return 1;
case Oslice:
if(n->right->right->op != Onothing || n->ty == tstring)
return 0;
return 1;
case Oindex:
case Oinds:
case Oindx:
return 1;
case Otuple:
for(nn = n->left; nn != nil; nn = nn->right){
s = circlval(nn->left, lval);
if(s != 1)
return s;
}
return 1;
default:
return 0;
}
return 0;
}
int
mathchk(Node *n, int realok)
{
Type *tr, *tl;
tl = n->left->ty;
tr = n->right->ty;
if(tr != tl && !tequal(tl, tr)){
nerror(n, "type clash in %Q %O %Q", n->left, n->op, n->right);
return 0;
}
n->ty = tr;
switch(tr->kind){
case Tint:
case Tbig:
case Tbyte:
return 1;
case Tstring:
switch(n->op){
case Oadd:
case Oaddas:
case Ogt:
case Ogeq:
case Olt:
case Oleq:
return 1;
}
break;
case Treal:
case Tfix:
if(realok)
return 1;
break;
}
nerror(n, "cannot %O %Q and %Q", n->op, n->left, n->right);
return 0;
}
int
shiftchk(Node *n)
{
Node *left, *right;
right = n->right;
left = n->left;
n->ty = left->ty;
switch(n->ty->kind){
case Tint:
case Tbyte:
case Tbig:
if(right->ty->kind != Tint){
nerror(n, "shift %Q is not an int", right);
return 0;
}
return 1;
}
nerror(n, "cannot %Q %O %Q", left, n->op, right);
return 0;
}
/*
* check for any tany's in t
*/
int
specific(Type *t)
{
Decl *d;
if(t == nil)
return 0;
switch(t->kind){
case Terror:
case Tnone:
case Tint:
case Tbig:
case Tstring:
case Tbyte:
case Treal:
case Tfn:
case Tadt:
case Tadtpick:
case Tmodule:
case Tfix:
return 1;
case Tany:
return 0;
case Tpoly:
return 1;
case Tref:
case Tlist:
case Tarray:
case Tchan:
return specific(t->tof);
case Ttuple:
case Texception:
for(d = t->ids; d != nil; d = d->next)
if(!specific(d->ty))
return 0;
return 1;
}
fatal("unknown type %T in specific", t);
return 0;
}
/*
* infer the type of all variable in n from t
* n is the left-hand exp of a := exp
*/
int
declasinfer(Node *n, Type *t)
{
Decl *ids;
int ok;
if(t->kind == Texception){
if(t->cons)
return 0;
t = mkextuptype(t);
}
switch(n->op){
case Otuple:
if(t->kind != Ttuple && t->kind != Tadt && t->kind != Tadtpick)
return 0;
ok = 1;
n->ty = t;
n = n->left;
ids = t->ids;
if(t->kind == Tadtpick)
ids = t->tof->ids->next;
for(; n != nil && ids != nil; ids = ids->next){
if(ids->store != Dfield)
continue;
ok &= declasinfer(n->left, ids->ty);
n = n->right;
}
for(; ids != nil; ids = ids->next)
if(ids->store == Dfield)
break;
if(n != nil || ids != nil)
return 0;
return ok;
case Oname:
topvartype(t, n->decl, 0, 0);
if(n->decl == nildecl)
return 1;
n->decl->ty = t;
n->ty = t;
shareloc(n->decl);
return 1;
}
fatal("unknown op %n in declasinfer", n);
return 0;
}
/*
* an error occured in declaring n;
* set all decl identifiers to Dwundef
* so further errors are squashed.
*/
void
declaserr(Node *n)
{
switch(n->op){
case Otuple:
for(n = n->left; n != nil; n = n->right)
declaserr(n->left);
return;
case Oname:
if(n->decl != nildecl)
n->decl->store = Dwundef;
return;
}
fatal("unknown op %n in declaserr", n);
}
int
argcompat(Node *n, Decl *f, Node *a)
{
for(; a != nil; a = a->right){
if(f == nil){
nerror(n, "%V: too many function arguments", n->left);
return 0;
}
if(!tcompat(f->ty, a->left->ty, 0)){
nerror(n, "%V: argument type mismatch: expected %T saw %Q",
n->left, f->ty, a->left);
return 0;
}
if(a->left->ty == tany)
a->left->ty = f->ty;
f = f->next;
}
if(f != nil){
nerror(n, "%V: too few function arguments", n->left);
return 0;
}
return 1;
}
/*
* fn is Odot(adt, methid)
* pass adt implicitly if needed
* if not, any side effect of adt will be ignored
*/
Node*
passimplicit(Node *fn, Node *args)
{
Node *n;
Type *t;
t = fn->ty;
n = fn->left;
if(t->ids == nil || !t->ids->implicit){
if(!isfnrefty(t) && hasside(n, 1))
nwarn(fn, "result of expression %V ignored", n);
return args;
}
if(n->op == Oname && n->decl->store == Dtype){
nerror(n, "%V is a type and cannot be a self argument", n);
n = mkn(Onothing, nil, nil);
n->src = fn->src;
n->ty = t->ids->ty;
}
args = mkn(Oseq, n, args);
args->src = n->src;
return args;
}
static int
mem(Type *t, Decl *d)
{
for( ; d != nil; d = d->next)
if(d->ty == t) /* was if(d->ty == t || tequal(d->ty, t)) */
return 1;
return 0;
}
static int
memp(Type *t, Decl *f)
{
return mem(t, f->ty->polys) || mem(t, encpolys(f));
}
static void
passfns0(Src *src, Decl *fn, Node *args0, Node **args, Node **a, Tpair *tp, Decl *polys)
{
Decl *id, *idt, *idf, *dot;
Type *tt;
Sym *sym;
Node *n, *na, *mod;
Tpair *p;
if(debug['w']){
print("polys: ");
for(id=polys; id!=nil; id=id->next) print("%s ", id->sym->name);
print("\nmap: ");
for(p=tp; p!=nil; p=p->nxt) print("%T -> %T ", p->t1, p->t2);
print("\n");
}
for(idt = polys; idt != nil; idt = idt->next){
tt = valtmap(idt->ty, tp);
if(tt->kind == Tpoly && fndec != nil && !memp(tt, fndec))
error(src->start, "cannot determine the instantiated type of %T", tt);
for(idf = idt->ty->ids; idf != nil; idf = idf->next){
sym = idf->sym;
id = fnlookup(sym, tt, &mod);
while(id != nil && id->link != nil)
id = id->link;
if(debug['v']) print("fnlookup: %p\n", id);
if(id == nil) /* error flagged already */
continue;
id->refs++;
id->caninline = -1;
if(tt->kind == Tmodule){ /* mod an actual parameter */
for(;;){
if(args0 != nil && tequal(tt, args0->left->ty)){
mod = args0->left;
break;
}
if(args0 == nil)
break;
args0 = args0->right;
}
}
if(mod == nil && (dot = module(id)) != nil && !isimpmod(dot->sym))
error(src->start, "cannot use %s without importing %s from a variable", id->sym->name, id->dot->sym->name);
if(debug['U']) print("fp: %s %s %s\n", fn->sym->name, mod ? mod->decl->sym->name : "nil", id->sym->name);
n = mkn(Ofnptr, mod, mkdeclname(src, id));
n->src = *src;
n->decl = fn;
if(tt->kind == Tpoly)
n->flags = FNPTRA;
else
n->flags = 0;
na = mkn(Oseq, n, nil);
if(*a == nil)
*args = na;
else
(*a)->right = na;
n = mkn(Ofnptr, mod, mkdeclname(src, id));
n->src = *src;
n->decl = fn;
if(tt->kind == Tpoly)
n->flags = FNPTRA|FNPTR2;
else
n->flags = FNPTR2;
*a = na->right = mkn(Oseq, n, nil);
}
if(args0 != nil)
args0 = args0->right;
}
}
Node*
passfns(Src *src, Decl *fn, Node *left, Node *args, Type *adt, Tpair *tp)
{
Node *a, *args0;
a = nil;
args0 = args;
if(args != nil)
for(a = args; a->right != nil; a = a->right)
;
passfns0(src, fn, args0, &args, &a, tp, ispoly(fn) ? fn->ty->polys : left->ty->tof->polys);
if(adt != nil)
passfns0(src, fn, args0, &args, &a, adt->u.tmap, ispoly(fn) ? encpolys(fn) : nil);
return args;
}
/*
* check the types for a function with a variable number of arguments
* last typed argument must be a constant string, and must use the
* print format for describing arguments.
*/
Type*
mkvarargs(Node *n, Node *args)
{
Node *s, *a;
Decl *f, *last, *va;
Type *nt;
nt = copytypeids(n->ty);
n->ty = nt;
f = n->ty->ids;
last = nil;
if(f == nil){
nerror(n, "%V's type is illegal", n);
return nt;
}
s = args;
for(a = args; a != nil; a = a->right){
if(f == nil)
break;
if(!tcompat(f->ty, a->left->ty, 0)){
nerror(n, "%V: argument type mismatch: expected %T saw %Q",
n, f->ty, a->left);
return nt;
}
if(a->left->ty == tany)
a->left->ty = f->ty;
last = f;
f = f->next;
s = a;
}
if(f != nil){
nerror(n, "%V: too few function arguments", n);
return nt;
}
s->left = fold(s->left);
s = s->left;
if(s->ty != tstring || s->op != Oconst){
nerror(args, "%V: format argument %Q is not a string constant", n, s);
return nt;
}
fmtcheck(n, s, a);
va = tuplefields(a);
if(last == nil)
nt->ids = va;
else
last->next = va;
return nt;
}
/*
* check that a print style format string matches its arguments
*/
void
fmtcheck(Node *f, Node *fmtarg, Node *va)
{
Sym *fmt;
Rune r;
char *s, flags[10];
int i, c, n1, n2, dot, verb, flag, ns, lens, fmtstart;
Type *ty;
fmt = fmtarg->decl->sym;
s = fmt->name;
lens = fmt->len;
ns = 0;
while(ns < lens){
c = s[ns++];
if(c != '%')
continue;
verb = -1;
n1 = 0;
n2 = 0;
dot = 0;
flag = 0;
fmtstart = ns - 1;
while(ns < lens && verb < 0){
c = s[ns++];
switch(c){
default:
chartorune(&r, &s[ns-1]);
nerror(f, "%V: invalid character %C in format '%.*s'", f, r, ns-fmtstart, &s[fmtstart]);
return;
case '.':
if(dot){
nerror(f, "%V: invalid format '%.*s'", f, ns-fmtstart, &s[fmtstart]);
return;
}
n1 = 1;
dot = 1;
continue;
case '*':
if(!n1)
n1 = 1;
else if(!n2 && dot)
n2 = 1;
else{
nerror(f, "%V: invalid format '%.*s'", f, ns-fmtstart, &s[fmtstart]);
return;
}
if(va == nil){
nerror(f, "%V: too few arguments for format '%.*s'",
f, ns-fmtstart, &s[fmtstart]);
return;
}
if(va->left->ty->kind != Tint){
nerror(f, "%V: format '%.*s' incompatible with argument %Q",
f, ns-fmtstart, &s[fmtstart], va->left);
return;
}
va = va->right;
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
while(ns < lens && s[ns] >= '0' && s[ns] <= '9')
ns++;
if(!n1)
n1 = 1;
else if(!n2 && dot)
n2 = 1;
else{
nerror(f, "%V: invalid format '%.*s'", f, ns-fmtstart, &s[fmtstart]);
return;
}
break;
case '+':
case '-':
case '#':
case ',':
case 'b':
case 'u':
for(i = 0; i < flag; i++){
if(flags[i] == c){
nerror(f, "%V: duplicate flag %c in format '%.*s'",
f, c, ns-fmtstart, &s[fmtstart]);
return;
}
}
flags[flag++] = c;
if(flag >= sizeof flags){
nerror(f, "too many flags in format '%.*s'", ns-fmtstart, &s[fmtstart]);
return;
}
break;
case '%':
case 'r':
verb = Tnone;
break;
case 'H':
verb = Tany;
break;
case 'c':
verb = Tint;
break;
case 'd':
case 'o':
case 'x':
case 'X':
verb = Tint;
for(i = 0; i < flag; i++){
if(flags[i] == 'b'){
verb = Tbig;
break;
}
}
break;
case 'e':
case 'f':
case 'g':
case 'E':
case 'G':
verb = Treal;
break;
case 's':
case 'q':
verb = Tstring;
break;
}
}
if(verb != Tnone){
if(verb < 0){
nerror(f, "%V: incomplete format '%.*s'", f, ns-fmtstart, &s[fmtstart]);
return;
}
if(va == nil){
nerror(f, "%V: too few arguments for format '%.*s'", f, ns-fmtstart, &s[fmtstart]);
return;
}
ty = va->left->ty;
if(ty->kind == Texception)
ty = mkextuptype(ty);
switch(verb){
case Tint:
switch(ty->kind){
case Tstring:
case Tarray:
case Tref:
case Tchan:
case Tlist:
case Tmodule:
if(c == 'x' || c == 'X')
verb = ty->kind;
break;
}
break;
case Tany:
if(tattr[ty->kind].isptr)
verb = ty->kind;
break;
}
if(verb != ty->kind){
nerror(f, "%V: format '%.*s' incompatible with argument %Q", f, ns-fmtstart, &s[fmtstart], va->left);
return;
}
va = va->right;
}
}
if(va != nil)
nerror(f, "%V: more arguments than formats", f);
}
Decl*
tuplefields(Node *n)
{
Decl *d, *h, **last;
h = nil;
last = &h;
for(; n != nil; n = n->right){
d = mkdecl(&n->left->src, Dfield, n->left->ty);
*last = d;
last = &d->next;
}
return h;
}
/*
* make explicit indices for every element in an array initializer
* return the maximum index
* sort the indices and check for duplicates
*/
int
assignindices(Node *ar)
{
Node *wild, *off, *size, *inits, *n, *q;
Type *t;
Case *c;
int amax, max, last, nlab, ok;
amax = 0x7fffffff;
size = dupn(0, &nosrc, ar->left);
if(size->ty == tint){
size = fold(size);
if(size->op == Oconst)
amax = size->val;
}
inits = ar->right;
max = -1;
last = -1;
t = inits->left->ty;
wild = nil;
nlab = 0;
ok = 1;
for(n = inits; n != nil; n = n->right){
if(!tcompat(t, n->left->ty, 0)){
t = tparent(t, n->left->ty);
if(!tcompat(t, n->left->ty, 0)){
nerror(n->left, "inconsistent types %T and %T and in array initializer", t, n->left->ty);
return -1;
}
else
inits->left->ty = t;
}
if(t == tany)
t = n->left->ty;
/*
* make up an index if there isn't one
*/
if(n->left->left == nil)
n->left->left = mkn(Oseq, mkconst(&n->left->right->src, last + 1), nil);
for(q = n->left->left; q != nil; q = q->right){
off = q->left;
if(off->ty != tint){
nerror(off, "array index %Q is not an int", off);
ok = 0;
continue;
}
off = fold(off);
switch(off->op){
case Owild:
if(wild != nil)
nerror(off, "array index * duplicated on line %L", wild->src.start);
wild = off;
continue;
case Orange:
if(off->left->op != Oconst || off->right->op != Oconst){
nerror(off, "range %V is not constant", off);
off = nil;
}else if(off->left->val < 0 || off->right->val >= amax){
nerror(off, "array index %V out of bounds", off);
off = nil;
}else
last = off->right->val;
break;
case Oconst:
last = off->val;
if(off->val < 0 || off->val >= amax){
nerror(off, "array index %V out of bounds", off);
off = nil;
}
break;
case Onothing:
/* get here from a syntax error */
off = nil;
break;
default:
nerror(off, "array index %V is not constant", off);
off = nil;
break;
}
nlab++;
if(off == nil){
off = mkconst(&n->left->right->src, last);
ok = 0;
}
if(last > max)
max = last;
q->left = off;
}
}
/*
* fix up types of nil elements
*/
for(n = inits; n != nil; n = n->right)
if(n->left->ty == tany)
n->left->ty = t;
if(!ok)
return -1;
c = checklabels(inits, tint, nlab, "array index");
t = mktype(&inits->src.start, &inits->src.stop, Tainit, nil, nil);
inits->ty = t;
t->cse = c;
return max + 1;
}
/*
* check the labels of a case statment
*/
void
casecheck(Node *cn, Type *ret)
{
Node *n, *q, *wild, *left, *arg;
Type *t;
Case *c;
Ok rok;
int nlab, ok, op;
rok = echeck(cn->left, 0, 0, nil);
cn->right = scheck(cn->right, ret, Sother);
if(!rok.ok)
return;
arg = cn->left;
t = arg->ty;
if(t != tint && t != tbig && t != tstring){
nerror(cn, "case argument %Q is not an int or big or string", arg);
return;
}
wild = nil;
nlab= 0;
ok = 1;
for(n = cn->right; n != nil; n = n->right){
q = n->left->left;
if(n->left->right->right == nil)
nwarn(q, "no body for case qualifier %V", q);
for(; q != nil; q = q->right){
left = fold(q->left);
q->left = left;
switch(left->op){
case Owild:
if(wild != nil)
nerror(left, "case qualifier * duplicated on line %L", wild->src.start);
wild = left;
break;
case Orange:
if(left->ty != t)
nerror(left, "case qualifier %Q clashes with %Q", left, arg);
else if(left->left->op != Oconst || left->right->op != Oconst){
nerror(left, "case range %V is not constant", left);
ok = 0;
}
nlab++;
break;
default:
if(left->ty != t){
nerror(left, "case qualifier %Q clashes with %Q", left, arg);
ok = 0;
}else if(left->op != Oconst){
nerror(left, "case qualifier %V is not constant", left);
ok = 0;
}
nlab++;
break;
}
}
}
if(!ok)
return;
c = checklabels(cn->right, t, nlab, "case qualifier");
op = Tcase;
if(t == tbig)
op = Tcasel;
else if(t == tstring)
op = Tcasec;
t = mktype(&cn->src.start, &cn->src.stop, op, nil, nil);
cn->ty = t;
t->cse = c;
}
/*
* check the labels and bodies of a pick statment
*/
void
pickcheck(Node *n, Type *ret)
{
Node *w, *arg, *qs, *q, *qt, *left, **tags;
Decl *id, *d;
Type *t, *argty;
Case *c;
Ok rok;
int ok, nlab;
arg = n->left->right;
rok = echeck(arg, 0, 0, nil);
if(!rok.allok)
return;
t = arg->ty;
if(t->kind == Tref)
t = t->tof;
if(arg->ty->kind != Tref || t->kind != Tadt || t->tags == nil){
nerror(arg, "pick argument %Q is not a ref adt with pick tags", arg);
return;
}
argty = usetype(mktype(&arg->ty->src.start, &arg->ty->src.stop, Tref, t, nil));
arg = n->left->left;
pushscope(nil, Sother);
dasdecl(arg);
arg->decl->ty = argty;
arg->ty = argty;
tags = allocmem(t->decl->tag * sizeof *tags);
memset(tags, 0, t->decl->tag * sizeof *tags);
w = nil;
ok = 1;
nlab = 0;
for(qs = n->right; qs != nil; qs = qs->right){
qt = nil;
for(q = qs->left->left; q != nil; q = q->right){
left = q->left;
switch(left->op){
case Owild:
/* left->ty = tnone; */
left->ty = t;
if(w != nil)
nerror(left, "pick qualifier * duplicated on line %L", w->src.start);
w = left;
break;
case Oname:
id = namedot(t->tags, left->decl->sym);
if(id == nil){
nerror(left, "pick qualifier %V is not a member of %Q", left, arg);
ok = 0;
continue;
}
left->decl = id;
left->ty = id->ty;
if(tags[id->tag] != nil){
nerror(left, "pick qualifier %V duplicated on line %L",
left, tags[id->tag]->src.start);
ok = 0;
}
tags[id->tag] = left;
nlab++;
break;
default:
fatal("pickcheck can't handle %n", q);
break;
}
if(qt == nil)
qt = left;
else if(!tequal(qt->ty, left->ty))
nerror(left, "type clash in pick qualifiers %Q and %Q", qt, left);
}
argty->tof = t;
if(qt != nil)
argty->tof = qt->ty;
qs->left->right = scheck(qs->left->right, ret, Sother);
if(qs->left->right == nil)
nwarn(qs->left->left, "no body for pick qualifier %V", qs->left->left);
}
argty->tof = t;
for(qs = n->right; qs != nil; qs = qs->right)
for(q = qs->left->left; q != nil; q = q->right)
q->left = fold(q->left);
d = popscope();
d->refs++;
if(d->next != nil)
fatal("pickcheck: installing more than one id");
fndecls = appdecls(fndecls, d);
if(!ok)
return;
c = checklabels(n->right, tint, nlab, "pick qualifier");
t = mktype(&n->src.start, &n->src.stop, Tcase, nil, nil);
n->ty = t;
t->cse = c;
}
void
exccheck(Node *en, Type *ret)
{
Decl *ed;
Node *n, *q, *wild, *left, *oinexcept;
Type *t, *qt;
Case *c;
int nlab, ok;
Ok rok;
char buf[32];
static int nexc;
pushscope(nil, Sother);
if(en->left == nil){
seprint(buf, buf+sizeof(buf), ".ex%d", nexc++);
en->left = mkdeclname(&en->src, mkids(&en->src, enter(buf, 0), texception, nil));
}
oinexcept = inexcept;
inexcept = en->left;
dasdecl(en->left);
en->left->ty = en->left->decl->ty = texception;
ed = en->left->decl;
/* en->right = scheck(en->right, ret, Sother); */
t = tstring;
wild = nil;
nlab = 0;
ok = 1;
for(n = en->right; n != nil; n = n->right){
qt = nil;
for(q = n->left->left; q != nil; q = q->right){
left = q->left;
switch(left->op){
case Owild:
left->ty = texception;
if(wild != nil)
nerror(left, "exception qualifier * duplicated on line %L", wild->src.start);
wild = left;
break;
case Orange:
left->ty = tnone;
nerror(left, "exception qualifier %V is illegal", left);
ok = 0;
break;
default:
rok = echeck(left, 0, 0, nil);
if(!rok.ok){
ok = 0;
break;
}
left = q->left = fold(left);
if(left->ty != t && left->ty->kind != Texception){
nerror(left, "exception qualifier %Q is not a string or exception", left);
ok = 0;
}else if(left->op != Oconst){
nerror(left, "exception qualifier %V is not constant", left);
ok = 0;
}
else if(left->ty != t)
left->ty = mkextype(left->ty);
nlab++;
break;
}
if(qt == nil)
qt = left->ty;
else if(!tequal(qt, left->ty))
qt = texception;
}
if(qt != nil)
ed->ty = qt;
n->left->right = scheck(n->left->right, ret, Sother);
if(n->left->right->right == nil)
nwarn(n->left->left, "no body for exception qualifier %V", n->left->left);
}
ed->ty = texception;
inexcept = oinexcept;
if(!ok)
return;
c = checklabels(en->right, texception, nlab, "exception qualifier");
t = mktype(&en->src.start, &en->src.stop, Texcept, nil, nil);
en->ty = t;
t->cse = c;
ed = popscope();
fndecls = appdecls(fndecls, ed);
}
/*
* check array and case labels for validity
*/
Case *
checklabels(Node *inits, Type *ctype, int nlab, char *title)
{
Node *n, *p, *q, *wild;
Label *labs, *aux;
Case *c;
char buf[256], buf1[256];
int i, e;
labs = allocmem(nlab * sizeof *labs);
i = 0;
wild = nil;
for(n = inits; n != nil; n = n->right){
for(q = n->left->left; q != nil; q = q->right){
switch(q->left->op){
case Oconst:
labs[i].start = q->left;
labs[i].stop = q->left;
labs[i++].node = n->left;
break;
case Orange:
labs[i].start = q->left->left;
labs[i].stop = q->left->right;
labs[i++].node = n->left;
break;
case Owild:
wild = n->left;
break;
default:
fatal("bogus index in checklabels");
break;
}
}
}
if(i != nlab)
fatal("bad label count: %d then %d", nlab, i);
aux = allocmem(nlab * sizeof *aux);
casesort(ctype, aux, labs, 0, nlab);
for(i = 0; i < nlab; i++){
p = labs[i].stop;
if(casecmp(ctype, labs[i].start, p) > 0)
nerror(labs[i].start, "unmatchable %s %V", title, labs[i].node);
for(e = i + 1; e < nlab; e++){
if(casecmp(ctype, labs[e].start, p) <= 0){
eprintlist(buf, buf+sizeof(buf), labs[e].node->left, " or ");
eprintlist(buf1, buf1+sizeof(buf1), labs[e-1].node->left, " or ");
nerror(labs[e].start,"%s '%s' overlaps with '%s' on line %L",
title, buf, buf1, p->src.start);
}
/*
* check for merging case labels
*/
if(ctype != tint
|| labs[e].start->val != p->val+1
|| labs[e].node != labs[i].node)
break;
p = labs[e].stop;
}
if(e != i + 1){
labs[i].stop = p;
memmove(&labs[i+1], &labs[e], (nlab-e) * sizeof *labs);
nlab -= e - (i + 1);
}
}
free(aux);
c = allocmem(sizeof *c);
c->nlab = nlab;
c->nsnd = 0;
c->labs = labs;
c->wild = wild;
return c;
}
static int
matchcmp(Node *na, Node *nb)
{
Sym *a, *b;
int sa, sb;
a = na->decl->sym;
b = nb->decl->sym;
sa = a->len > 0 && a->name[a->len-1] == '*';
sb = b->len > 0 && b->name[b->len-1] == '*';
if(sa){
if(sb){
if(a->len == b->len)
return symcmp(a, b);
return b->len-a->len;
}
else
return 1;
}
else{
if(sb)
return -1;
else{
if(na->ty == tstring){
if(nb->ty == tstring)
return symcmp(a, b);
else
return 1;
}
else{
if(nb->ty == tstring)
return -1;
else
return symcmp(a, b);
}
}
}
}
int
casecmp(Type *ty, Node *a, Node *b)
{
if(ty == tint || ty == tbig){
if(a->val < b->val)
return -1;
if(a->val > b->val)
return 1;
return 0;
}
if(ty == texception)
return matchcmp(a, b);
return symcmp(a->decl->sym, b->decl->sym);
}
void
casesort(Type *t, Label *aux, Label *labs, int start, int stop)
{
int n, top, mid, base;
n = stop - start;
if(n <= 1)
return;
top = mid = start + n / 2;
casesort(t, aux, labs, start, top);
casesort(t, aux, labs, mid, stop);
/*
* merge together two sorted label arrays, yielding a sorted array
*/
n = 0;
base = start;
while(base < top && mid < stop){
if(casecmp(t, labs[base].start, labs[mid].start) <= 0)
aux[n++] = labs[base++];
else
aux[n++] = labs[mid++];
}
if(base < top)
memmove(&aux[n], &labs[base], (top-base) * sizeof *aux);
else if(mid < stop)
memmove(&aux[n], &labs[mid], (stop-mid) * sizeof *aux);
memmove(&labs[start], &aux[0], (stop-start) * sizeof *labs);
}
/*
* binary search for the label corresponding to a given value
*/
int
findlab(Type *ty, Node *v, Label *labs, int nlab)
{
int l, r, m;
if(nlab <= 1)
return 0;
l = 1;
r = nlab - 1;
while(l <= r){
m = (r + l) / 2;
if(casecmp(ty, labs[m].start, v) <= 0)
l = m + 1;
else
r = m - 1;
}
m = l - 1;
if(casecmp(ty, labs[m].start, v) > 0
|| casecmp(ty, labs[m].stop, v) < 0)
fatal("findlab out of range");
return m;
}
void
altcheck(Node *an, Type *ret)
{
Node *n, *q, *left, *op, *wild;
Case *c;
int ok, nsnd, nrcv;
an->left = scheck(an->left, ret, Sother);
ok = 1;
nsnd = 0;
nrcv = 0;
wild = nil;
for(n = an->left; n != nil; n = n->right){
q = n->left->right->left;
if(n->left->right->right == nil)
nwarn(q, "no body for alt guard %V", q);
for(; q != nil; q = q->right){
left = q->left;
switch(left->op){
case Owild:
if(wild != nil)
nerror(left, "alt guard * duplicated on line %L", wild->src.start);
wild = left;
break;
case Orange:
nerror(left, "alt guard %V is illegal", left);
ok = 0;
break;
default:
op = hascomm(left);
if(op == nil){
nerror(left, "alt guard %V has no communication", left);
ok = 0;
break;
}
if(op->op == Osnd)
nsnd++;
else
nrcv++;
break;
}
}
}
if(!ok)
return;
c = allocmem(sizeof *c);
c->nlab = nsnd + nrcv;
c->nsnd = nsnd;
c->wild = wild;
an->ty = mktalt(c);
}
Node*
hascomm(Node *n)
{
Node *r;
if(n == nil)
return nil;
if(n->op == Osnd || n->op == Orcv)
return n;
r = hascomm(n->left);
if(r != nil)
return r;
return hascomm(n->right);
}
void
raisescheck(Type *t)
{
Node *n, *nn;
Ok ok;
if(t->kind != Tfn)
return;
n = t->u.eraises;
for(nn = n->left; nn != nil; nn = nn->right){
ok = echeck(nn->left, 0, 0, nil);
if(ok.ok && nn->left->ty->kind != Texception)
nerror(n, "%V: illegal raises expression", nn->left);
}
}
typedef struct Elist Elist;
struct Elist{
Decl *d;
Elist *nxt;
};
static Elist*
emerge(Elist *el1, Elist *el2)
{
int f;
Elist *el, *nxt;
for( ; el1 != nil; el1 = nxt){
f = 0;
for(el = el2; el != nil; el = el->nxt){
if(el1->d == el->d){
f = 1;
break;
}
}
nxt = el1->nxt;
if(!f){
el1->nxt = el2;
el2 = el1;
}
}
return el2;
}
static Elist*
equals(Node *n)
{
Node *q, *nn;
Elist *e, *el;
el = nil;
for(q = n->left->left; q != nil; q = q->right){
nn = q->left;
if(nn->op == Owild)
return nil;
if(nn->ty->kind != Texception)
continue;
e = (Elist*)malloc(sizeof(Elist));
e->d = nn->decl;
e->nxt = el;
el = e;
}
return el;
}
static int
caught(Decl *d, Node *n)
{
Node *q, *nn;
for(n = n->right; n != nil; n = n->right){
for(q = n->left->left; q != nil; q = q->right){
nn = q->left;
if(nn->op == Owild)
return 1;
if(nn->ty->kind != Texception)
continue;
if(d == nn->decl)
return 1;
}
}
return 0;
}
static Elist*
raisecheck(Node *n, Elist *ql)
{
int exc;
Node *e;
Elist *el, *nel, *nxt;
if(n == nil)
return nil;
el = nil;
for(; n != nil; n = n->right){
switch(n->op){
case Oscope:
return raisecheck(n->right, ql);
case Olabel:
case Odo:
return raisecheck(n->right, ql);
case Oif:
case Ofor:
return emerge(raisecheck(n->right->left, ql),
raisecheck(n->right->right, ql));
case Oalt:
case Ocase:
case Opick:
case Oexcept:
exc = n->op == Oexcept;
for(n = n->right; n != nil; n = n->right){
ql = nil;
if(exc)
ql = equals(n);
el = emerge(raisecheck(n->left->right, ql), el);
}
return el;
case Oseq:
el = emerge(raisecheck(n->left, ql), el);
break;
case Oexstmt:
el = raisecheck(n->left, ql);
nel = nil;
for( ; el != nil; el = nxt){
nxt = el->nxt;
if(!caught(el->d, n->right)){
el->nxt = nel;
nel = el;
}
}
return emerge(nel, raisecheck(n->right, ql));
case Oraise:
e = n->left;
if(e->ty && e->ty->kind == Texception){
if(!e->ty->cons)
return ql;
if(e->op == Ocall)
e = e->left;
if(e->op == Omdot)
e = e->right;
if(e->op != Oname)
fatal("exception %n not a name", e);
el = (Elist*)malloc(sizeof(Elist));
el->d = e->decl;
el->nxt = nil;
return el;
}
return nil;
default:
return nil;
}
}
return el;
}
void
checkraises(Node *n)
{
int f;
Decl *d;
Elist *e, *el;
Node *es, *nn;
el = raisecheck(n->right, nil);
es = n->ty->u.eraises;
if(es != nil){
for(nn = es->left; nn != nil; nn = nn->right){
d = nn->left->decl;
f = 0;
for(e = el; e != nil; e = e->nxt){
if(d == e->d){
f = 1;
e->d = nil;
break;
}
}
if(!f)
nwarn(n, "function %V does not raise %s but declared", n->left, d->sym->name);
}
}
for(e = el; e != nil; e = e->nxt)
if(e->d != nil)
nwarn(n, "function %V raises %s but not declared", n->left, e->d->sym->name);
}
/* sort all globals in modules now that we've finished with 'last' pointers
* and before any code generation
*/
void
gsort(Node *n)
{
for(;;){
if(n == nil)
return;
if(n->op != Oseq)
break;
gsort(n->left);
n = n->right;
}
if(n->op == Omoddecl && n->ty->ok & OKverify){
n->ty->ids = namesort(n->ty->ids);
sizeids(n->ty->ids, 0);
}
}