ref: 680f6e2dab5e05ccc2726a0bb5cc2b4ad2425903
dir: /cc1/decl.c/
#include <inttypes.h>
#include <setjmp.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../inc/sizes.h"
#include "../inc/cc.h"
#include "cc1.h"
#define NOSCLASS 0
struct declarators {
unsigned char nr;
struct declarator {
unsigned char op;
unsigned short nelem;
Symbol *sym;
Type **tpars;
Symbol **pars;
} d [NR_DECLARATORS];
};
struct decl {
unsigned ns;
int sclass;
Symbol *sym;
Symbol **pars;
Type *type;
Type *parent;
};
static void
push(struct declarators *dp, unsigned op, ...)
{
va_list va;
unsigned n;
struct declarator *p;
va_start(va, op);
if ((n = dp->nr++) == NR_DECLARATORS)
error("too much declarators");
p = &dp->d[n];
p->op = op;
p->tpars = NULL;
switch (op) {
case ARY:
p->nelem = va_arg(va, unsigned);
break;
case FTN:
p->nelem = va_arg(va, unsigned);
p->tpars = va_arg(va, Type **);
p->pars = va_arg(va, Symbol **);
break;
case IDEN:
p->sym = va_arg(va, Symbol *);
break;
}
va_end(va);
}
static bool
pop(struct declarators *dp, struct decl *dcl)
{
struct declarator *p;
if (dp->nr == 0)
return 0;
p = &dp->d[--dp->nr];
if (p->op == IDEN) {
dcl->sym = p->sym;
return 1;
}
if (dcl->type->op == FTN) {
/*
* constructor applied to a
* function. We don't need
* the parameter symbols anymore.
*/
free(dcl->pars);
popctx();
dcl->pars = NULL;
}
if (p->op == FTN)
dcl->pars = p->pars;
dcl->type = mktype(dcl->type, p->op, p->nelem, p->tpars);
return 1;
}
static void
arydcl(struct declarators *dp)
{
Node *np = NULL;
TINT n;
expect('[');
if (yytoken != ']') {
if ((np = iconstexpr()) == NULL)
error("invalid storage size");
}
expect(']');
n = (np == NULL) ? 0 : np->sym->u.i;
freetree(np);
push(dp, ARY, n);
}
static Symbol *
parameter(struct decl *dcl)
{
Symbol *sym = dcl->sym;
Type *funtp = dcl->parent, *tp = dcl->type;
size_t n = funtp->n.elem;
char *name = sym->name;
sym->type = tp;
if (n == -1)
error("'void' must be the only parameter");
switch (dcl->sclass) {
case STATIC:
case EXTERN:
case AUTO:
errorp("bad storage class in function parameter");
break;
case REGISTER:
sym->flags |= ISREGISTER;
break;
case NOSCLASS:
sym->flags |= ISAUTO;
break;
}
switch (tp->op) {
case VOID:
if (n != 0)
error("incorrect void parameter");
if (dcl->sclass)
error("void as unique parameter may not be qualified");
funtp->n.elem = -1;
return NULL;
case ARY:
tp = mktype(tp->type, PTR, 0, NULL);
break;
case FTN:
error("incorrect function type for a function parameter");
}
if (name) {
if ((sym = install(NS_IDEN, sym)) == NULL)
error("redefinition of parameter '%s'", name);
}
sym->type = tp;
sym->flags |= ISUSED; /* avoid non used warnings in prototypes */
if (n == NR_FUNPARAM)
error("too much parameters in function definition");
funtp->p.pars = xrealloc(funtp->p.pars, ++n * sizeof(Type *));
funtp->p.pars[n-1] = tp;
funtp->n.elem = n;
return sym;
}
static Symbol *dodcl(int rep,
Symbol *(*fun)(struct decl *),
unsigned ns,
Type *type);
static void
fundcl(struct declarators *dp)
{
Type type = {.n = {.elem = -1}, .p = {.pars= NULL}};
Symbol *syms[NR_FUNPARAM], **sp;
size_t size;
Symbol *pars = NULL;
pushctx();
expect('(');
if (!accept(')')) {
type.n.elem = 0;
sp = syms;
do
*sp++ = dodcl(0, parameter, NS_IDEN, &type);
while (accept(','));
expect(')');
if (type.n.elem != -1) {
size = type.n.elem * sizeof(Symbol *);
pars = memcpy(xmalloc(size), syms, size);
}
}
push(dp, FTN, type.n.elem, type.p.pars, pars);
}
static void declarator(struct declarators *dp, unsigned ns);
static void
directdcl(struct declarators *dp, unsigned ns)
{
Symbol *sym;
static int nested;
if (accept('(')) {
if (nested == NR_SUBTYPE)
error("too declarators nested by parentheses");
++nested;
declarator(dp, ns);
--nested;
expect(')');
} else {
if (yytoken == IDEN || yytoken == TYPEIDEN) {
sym = yylval.sym;
next();
} else {
sym = newsym(ns);
}
push(dp, IDEN, sym);
}
for (;;) {
switch (yytoken) {
case '(': fundcl(dp); break;
case '[': arydcl(dp); break;
default: return;
}
}
}
static void
declarator(struct declarators *dp, unsigned ns)
{
unsigned n;
for (n = 0; accept('*'); ++n) {
while (accept(TQUALIFIER))
/* nothing */;
}
directdcl(dp, ns);
while (n--)
push(dp, PTR);
}
static Type *structdcl(void), *enumdcl(void);
static Type *
specifier(int *sclass)
{
Type *tp = NULL;
unsigned spec, qlf, sign, type, cls, size;
spec = qlf = sign = type = cls = size = 0;
for (;;) {
unsigned *p;
Type *(*dcl)(void) = NULL;
switch (yytoken) {
case SCLASS:
p = &cls;
break;
case TQUALIFIER:
if (qlf && qlf != RESTRICT)
errorp("invalid type specification");
qlf |= yylval.token;
next();
continue;
case TYPEIDEN:
if (type)
goto return_type;
tp = yylval.sym->type;
p = &type;
break;
case TYPE:
switch (yylval.token) {
case ENUM:
dcl = enumdcl;
p = &type;
break;
case STRUCT:
case UNION:
dcl = structdcl;
p = &type;
break;
case VOID:
case BOOL:
case CHAR:
case INT:
case FLOAT:
case DOUBLE:
p = &type;
break;
case SIGNED:
case UNSIGNED:
p = &sign;
break;
case LONG:
if (size == LONG) {
yylval.token = LLONG;
size = 0;
break;
}
case SHORT:
p = &size;
break;
}
break;
default:
goto return_type;
}
if (*p)
errorp("invalid type specification");
*p = yylval.token;
if (dcl) {
if (size || sign)
errorp("invalid type specification");
tp = (*dcl)();
goto return_type;
} else {
next();
}
spec = 1;
}
return_type:
if (sclass)
*sclass = cls;
if (!tp) {
if (spec) {
tp = ctype(type, sign, size);
} else {
if (curctx != GLOBALCTX)
unexpected();
warn("type defaults to 'int' in declaration");
tp = inttype;
}
}
return tp;
}
/* TODO: check correctness of the initializator */
/* TODO: emit initializer */
static struct node *
initializer(Symbol *sym)
{
if (accept('{')) {
initializer(sym);
expect('}');
} else {
do {
expr();
} while (accept(','));
}
return NULL;
}
static Symbol *
newtag(void)
{
Symbol *sym;
int op, tag = yylval.token;
static unsigned ns = NS_STRUCTS;
setnamespace(NS_TAG);
next();
switch (yytoken) {
case IDEN:
case TYPEIDEN:
sym = yylval.sym;
if ((sym->flags & ISDECLARED) == 0)
install(NS_TAG, yylval.sym);
next();
break;
default:
sym = newsym(NS_TAG);
break;
}
if (!sym->type) {
Type *tp;
if (ns == NS_STRUCTS + NR_MAXSTRUCTS)
error("too much tags declared");
tp = mktype(NULL, tag, 0, NULL);
tp->ns = ns++;
tp->p.fields = NULL;
sym->type = tp;
tp->tag = sym;
}
if ((op = sym->type->op) != tag && op != INT)
error("'%s' defined as wrong kind of tag", sym->name);
return sym;
}
/* TODO: bitfields */
static void fieldlist(Type *tp);
static Type *
structdcl(void)
{
Symbol *sym;
Type *tp;
static int nested;
sym = newtag();
tp = sym->type;
if (!accept('{'))
return tp;
if (tp->defined)
error("redefinition of struct/union '%s'", sym->name);
tp->defined = 1;
if (nested == NR_STRUCT_LEVEL)
error("too levels of nested structure or union definitions");
++nested;
while (!accept('}'))
fieldlist(tp);
--nested;
return tp;
}
static Type *
enumdcl(void)
{
Type *tp;
Symbol *sym, *tagsym;
int val, nctes;
tagsym = newtag();
tp = tagsym->type;
if (!accept('{'))
return tp;
if (tp->defined)
error("redefinition of enumeration '%s'", tagsym->name);
tp->defined = 1;
for (nctes = val = 0; yytoken != ')'; ++nctes, ++val) {
if (yytoken != IDEN)
unexpected();
if ((sym = install(NS_IDEN, yylval.sym)) == NULL) {
error("'%s' redeclared as different kind of symbol",
yytext);
}
if (nctes == NR_ENUM_CTES)
error("too much enum constants in a single enum");
next();
sym->flags |= ISCONSTANT;
sym->type = inttype;
if (accept('=')) {
Node *np = iconstexpr();
if (np == NULL)
error("invalid enumeration value");
val = np->sym->u.i;
freetree(np);
}
sym->u.i = val;
if (!accept(','))
break;
}
expect('}');
return tp;
}
static Symbol *
type(struct decl *dcl)
{
Symbol *sym = dcl->sym;
if (dcl->sclass)
error("class storage in type name");
if (sym->name)
error("unexpected identifier in type name");
sym->type = dcl->type;
return sym;
}
static Symbol *
field(struct decl *dcl)
{
Symbol *sym = dcl->sym;
char *name = sym->name;
Type *structp = dcl->parent, *tp = dcl->type;
size_t n = structp->n.elem;
if (!name) {
sym->type = tp;
warn("empty declaration");
return sym;
}
if (dcl->sclass)
error("storage class in struct/union field");
if (tp->op == FTN)
error("invalid type in struct/union");
if (!tp->defined)
error("field '%s' has incomplete type", name);
if ((sym = install(dcl->ns, sym)) == NULL)
error("duplicated member '%s'", name);
sym->type = tp;
sym->flags |= ISFIELD;
if (n == NR_FIELDS)
error("too much fields in struct/union");
structp->p.fields = xrealloc(structp->p.fields, ++n * sizeof(*sym));
structp->p.fields[n-1] = sym;
structp->n.elem = n;
return sym;
}
static void
bad_storage(Type *tp, char *name)
{
if (tp->op != FTN)
errorp("incorrect storage class for file-scope declaration");
errorp("invalid storage class for function '%s'", name);
}
static Symbol *
identifier(struct decl *dcl)
{
Symbol *sym = dcl->sym;
Type *tp = dcl->type;
char *name = sym->name;
short flags;
int sclass = dcl->sclass;
if (!name) {
sym->type = tp;
switch (tp->op) {
default:
warn("empty declaration");
case STRUCT:
case UNION:
case ENUM:
return sym;
}
}
/* TODO: Add warning about ANSI limits */
if (!tp->defined && sclass != EXTERN)
error("declared variable '%s' of incomplete type", name);
if (tp->op == FTN) {
if (sclass == NOSCLASS)
sclass = EXTERN;
/*
* Ugly workaround to solve function declarations.
* A new context is added for the parameters,
* so at this point curctx is incremented by
* one when sym was parsed.
*/
--curctx;
sym = install(NS_IDEN, sym);
++curctx;
} else {
sym = install(NS_IDEN, sym);
}
if (sym == NULL) {
sym = dcl->sym;
if (!eqtype(sym->type, tp))
error("conflicting types for '%s'", name);
if (sym->token == TYPEIDEN && sclass != TYPEDEF ||
sym->token != TYPEIDEN && sclass == TYPEDEF)
goto redeclaration;
if (curctx != GLOBALCTX && tp->op != FTN) {
if (!(sym->flags & ISEXTERN) || sclass != EXTERN)
goto redeclaration;
} else {
sym->u.pars = dcl->pars;
flags = sym->flags;
switch (sclass) {
case REGISTER:
case AUTO:
bad_storage(tp, name);
break;
case NOSCLASS:
if ((flags & ISPRIVATE) == 0) {
flags &= ~ISEXTERN;
flags |= ISGLOBAL;
break;
}
errorp("non-static declaration of '%s' follows static declaration",
name);
break;
case TYPEDEF:
case EXTERN:
break;
case STATIC:
if ((flags & (ISGLOBAL|ISEXTERN)) == 0) {
flags |= ISPRIVATE;
break;
}
errorp("static declaration of '%s' follows non-static declaration",
name);
break;
}
}
sym->flags = flags;
} else {
sym->type = tp;
sym->u.pars = dcl->pars;
flags = sym->flags;
switch (sclass) {
case REGISTER:
case AUTO:
if (curctx == GLOBALCTX || tp->op == FTN) {
bad_storage(tp, name);
break;
}
flags |= (sclass == REGISTER) ? ISREGISTER : ISAUTO;
break;
case NOSCLASS:
flags |= (curctx == GLOBALCTX) ? ISGLOBAL : ISAUTO;
break;
case EXTERN:
flags |= ISEXTERN;
break;
case STATIC:
flags |= (curctx == GLOBALCTX) ? ISPRIVATE : ISLOCAL;
break;
case TYPEDEF:
sym->token = TYPEIDEN;
break;
}
sym->flags = flags;
}
if (accept('='))
initializer(sym);
/* TODO: disallow initializators in functions */
/* TODO: check if typedef has initializer */
/* TODO: check if the variable is extern and has initializer */
if (sym->token == IDEN && sym->type->op != FTN)
emit(ODECL, sym);
return sym;
redeclaration:
errorp("redeclaration of '%s'", name);
return sym;
}
static Symbol *
dodcl(int rep, Symbol *(*fun)(struct decl *), unsigned ns, Type *parent)
{
Symbol *sym;
Type *base;
struct decl dcl;
struct declarators stack;
dcl.ns = ns;
dcl.parent = parent;
base = specifier(&dcl.sclass);
do {
stack.nr = 0;
dcl.pars = NULL;
dcl.type = base;
declarator(&stack, ns);
while (pop(&stack, &dcl))
/* nothing */;
sym = (*fun)(&dcl);
} while (rep && accept(','));
return sym;
}
void
decl(void)
{
Symbol *sym;
if (accept(';'))
return;
sym = dodcl(1, identifier, NS_IDEN, NULL);
/*
* Functions only can appear at global context,
* but due to parameter context, we have to check
* against GLOBALCTX+1
*/
if (sym->type->op == FTN) {
if (curctx != GLOBALCTX+1)
goto prototype;
switch (yytoken) {
case '{':
case TYPEIDEN:
case TYPE:
case TQUALIFIER:
case SCLASS:
if (sym->token == TYPEIDEN)
error("function definition declared 'typedef'");
if (sym->flags & ISDEFINED)
error("redefinition of '%s'", sym->name);
if (sym->flags & ISEXTERN) {
sym->flags &= ~ISEXTERN;
sym->flags |= ISGLOBAL;
}
sym->flags |= ISDEFINED;
sym->flags &= ~ISEMITTED;
curfun = sym;
emit(OFUN, sym);
free(sym->u.pars);
compound(NULL, NULL, NULL);
emit(OEFUN, NULL);
curfun = NULL;
return;
default:
prototype:
emit(ODECL, sym);
free(sym->u.pars);
sym->u.pars = NULL;
popctx();
}
}
expect(';');
}
static void
fieldlist(Type *tp)
{
if (yytoken != ';')
dodcl(1, field, tp->ns, tp);
expect(';');
}
Type *
typename(void)
{
return dodcl(0, type, 0, NULL)->type;
}