ref: 6e35fce1673ee59c3bc1c302263ecb2e92fa5fe3
dir: /parse/stab.c/
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <stdarg.h>
#include <ctype.h>
#include <string.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "parse.h"
/* Allows us to look up types/traits by name nodes */
typedef struct Tydefn Tydefn;
typedef struct Traitdefn Traitdefn;
struct Tydefn {
int line;
Node *name;
Type *type;
};
struct Traitdefn {
int line;
Node *name;
Trait *trait;
};
#define Maxstabdepth 128
static Stab *stabstk[Maxstabdepth];
int stabstkoff;
/* scope management */
Stab *curstab()
{
assert(stabstkoff > 0);
return stabstk[stabstkoff - 1];
}
void pushstab(Stab *st)
{
assert(stabstkoff < Maxstabdepth);
stabstk[stabstkoff++] = st;
}
void popstab(void)
{
assert(stabstkoff > 0);
stabstkoff--;
}
/* name hashing: we want namespaced lookups to find the
* name even if we haven't set the namespace up, since
* we can update it after the fact. */
static ulong nsnamehash(void *n)
{
return strhash(namestr(n));
}
static int nsnameeq(void *a, void *b)
{
return a == b || !strcmp(namestr(a), namestr(b));
}
static ulong implhash(void *p)
{
Node *n;
ulong h;
n = p;
h = nsnamehash(n->impl.traitname);
h *= tyhash(n->impl.type);
return h;
}
static int impleq(void *pa, void *pb)
{
Node *a, *b;
a = pa;
b = pb;
if (nsnameeq(a->impl.traitname, b->impl.traitname))
return tyeq(a->impl.type, b->impl.type);
return 0;
}
Stab *mkstab()
{
Stab *st;
st = zalloc(sizeof(Stab));
st->ns = mkht(strhash, streq);
st->dcl = mkht(nsnamehash, nsnameeq);
st->ty = mkht(nsnamehash, nsnameeq);
st->tr = mkht(nsnamehash, nsnameeq);
st->uc = mkht(nsnamehash, nsnameeq);
st->impl = mkht(implhash, impleq);
return st;
}
/*
* Searches for declarations from current
* scope, and all enclosing scopes. Does
* not resolve namespaces -- that is the job
* of the caller of this function.
*
* If a resoved name is not global, and is
* not in the current scope, it is recorded
* in the scope's closure.
*/
Node *getdcl(Stab *st, Node *n)
{
Node *s;
Stab *orig;
orig = st;
do {
s = htget(st->dcl, n);
if (s) {
/* record that this is in the closure of this scope */
if (!st->closure)
st->closure = mkht(nsnamehash, nsnameeq);
if (st != orig && !n->decl.isglobl)
htput(st->closure, s->decl.name, s);
return s;
}
st = st->super;
} while (st);
return NULL;
}
Type *gettype_l(Stab *st, Node *n)
{
Tydefn *t;
if ((t = htget(st->ty, n)))
return t->type;
return NULL;
}
Type *gettype(Stab *st, Node *n)
{
Tydefn *t;
do {
if ((t = htget(st->ty, n)))
return t->type;
st = st->super;
} while (st);
return NULL;
}
Ucon *getucon(Stab *st, Node *n)
{
Ucon *uc;
do {
if ((uc = htget(st->uc, n)))
return uc;
st = st->super;
} while (st);
return NULL;
}
Trait *gettrait(Stab *st, Node *n)
{
Traitdefn *c;
do {
if ((c = htget(st->tr, n)))
return c->trait;
st = st->super;
} while (st);
return NULL;
}
Stab *getns_str(Stab *st, char *name)
{
Stab *s;
if (!strcmp(namestr(st->name), name))
return st;
do {
if ((s = htget(st->ns, name)))
return s;
st = st->super;
} while (st);
return NULL;
}
Stab *getns(Stab *st, Node *n)
{
return getns_str(st, namestr(n));
}
void putdcl(Stab *st, Node *s)
{
Node *d;
d = htget(st->dcl, s->decl.name);
if (d)
fatal(s->line, "%s already declared (on line %d)", namestr(s->decl.name), d->line);
forcedcl(st, s);
}
void forcedcl (Stab *st, Node *s) {
if (st->name)
setns(s->decl.name, namestr(st->name));
htput(st->dcl, s->decl.name, s);
assert(htget(st->dcl, s->decl.name) != NULL);
}
void updatetype(Stab *st, Node *n, Type *t)
{
Tydefn *td;
td = htget(st->ty, n);
if (!td)
die("No type %s to update", namestr(n));
td->type = t;
}
void puttype(Stab *st, Node *n, Type *t)
{
Tydefn *td;
if (gettype(st, n))
fatal(n->line, "Type %s already defined", tystr(gettype(st, n)));
td = xalloc(sizeof(Tydefn));
td->line = n->line;
td->name = n;
td->type = t;
if (st->name)
setns(n, namestr(st->name));
htput(st->ty, td->name, td);
}
void putucon(Stab *st, Ucon *uc)
{
if (getucon(st, uc->name))
fatal(uc->line, "union constructor %s already defined", namestr(uc->name));
htput(st->uc, uc->name, uc);
}
void puttrait(Stab *st, Node *n, Trait *c)
{
Traitdefn *td;
if (gettrait(st, n))
fatal(n->line, "Trait %s already defined", namestr(n));
if (gettype(st, n))
fatal(n->line, "Trait %s already defined as a type", namestr(n));
td = xalloc(sizeof(Tydefn));
td->line = n->line;
td->name = n;
td->trait = c;
htput(st->tr, td->name, td);
}
void putimpl(Stab *st, Node *n)
{
if (getimpl(st, n))
fatal(n->line, "Trait %s already implemented over %s", namestr(n->impl.traitname), tystr(n->impl.type));
if (st->name)
setns(n->impl.traitname, namestr(st->name));
htput(st->impl, n, n);
}
Node *getimpl(Stab *st, Node *n)
{
Node *imp;
do {
if ((imp = htget(st->impl, n)))
return imp;
st = st->super;
} while (st);
return NULL;
}
void putns(Stab *st, Stab *scope)
{
Stab *s;
s = getns(st, scope->name);
if (s)
fatal(scope->name->line, "Ns %s already defined", namestr(s->name));
htput(st->ns, namestr(scope->name), scope);
}
/*
* Sets the namespace of a symbol table, and
* changes the namespace of all contained symbols
* to match it.
*/
void updatens(Stab *st, char *name)
{
void **k;
size_t i, nk;
Tydefn *td;
if (st->name)
die("Stab %s already has namespace; Can't set to %s", namestr(st->name), name);
st->name = mkname(-1, name);
k = htkeys(st->dcl, &nk);
for (i = 0; i < nk; i++)
setns(k[i], name);
free(k);
k = htkeys(st->ty, &nk);
for (i = 0; i < nk; i++)
setns(k[i], name);
for (i = 0; i < nk; i++) {
td = htget(st->ty, k[i]);
if (td->type && td->type->type == Tyname)
setns(td->type->name, name);
}
free(k);
k = htkeys(st->ns, &nk);
for (i = 0; i < nk; i++)
setns(k[i], name);
free(k);
}