ref: 25ee0a4512e705ff8017b87c8fc6ae6dc94732ce
dir: /cc1/decl.c/
#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include "../inc/sizes.h"
#include "../inc/cc.h"
#include "cc1.h"
#define ID_EXPECTED 1
#define ID_ACCEPTED 2
#define ID_FORBIDDEN 3
/* TODO: check identifiers in enum declaration */
struct dcldata {
uint8_t op;
unsigned short nelem;
void *data;
};
static struct dcldata *
queue(struct dcldata *dp, uint8_t op, short nelem, void *data)
{
if (dp->op == 255)
error("too much declarators");
dp->op = op;
dp->nelem = nelem;
dp->data = data;
return dp + 1;
}
static struct dcldata *
arydcl(struct dcldata *dp)
{
expect('[');
expect(']');
return queue(dp, ARY, 0, NULL);
}
static Symbol *parameter(void);
static struct dcldata *
fundcl(struct dcldata *dp)
{
size_t siz;
uint8_t n, i, noname;
Type *pars[NR_FUNPARAM], **tp = pars;
Symbol *syms[NR_FUNPARAM], **sp = syms, *sym;
pushctx();
expect('(');
n = noname = 0;
do {
if ((sym = parameter()) == NULL) {
if (n == 0)
break;
error("incorrect void parameter");
}
if (n++ == NR_FUNPARAM)
error("too much parameters in function definition");
*sp++ = sym;
*tp++ = sym->type;
noname |= sym->name[0] == '\0';
} while (accept(','));
expect(')');
if (n != 0) {
siz = sizeof(*tp) * n;
tp = memcpy(xmalloc(siz), pars, siz);
} else {
tp = NULL;
}
if (yytoken != '{') {
/* it is only a prototype */
popctx();
} else {
/* it is a function definition */
if (noname)
error("parameter name omitted");
sp = syms;
for (i = 0; i < n; ++i)
emitdcl(*sp++);
}
return queue(dp, FTN, n, tp);
}
static Symbol *
newiden(uint8_t ns)
{
Symbol *sym;
extern uint8_t curctx;
if (yylval.sym && yylval.sym->ctx == curctx && yylval.sym->ns == ns)
error("redeclaration of '%s'", yytext);
sym = install(yytext, ns);
next();
return sym;
}
static struct dcldata *declarator0(struct dcldata *dp, uint8_t ns);
static struct dcldata *
directdcl(struct dcldata *dp, uint8_t ns)
{
Symbol *sym;
if (accept('(')) {
dp = declarator0(dp, ns);
expect(')');
} else {
if (yytoken == IDEN || yytoken == TYPEIDEN)
sym = newiden(ns);
else
sym = install("", ns);
dp = queue(dp, IDEN, 0, sym);
}
for (;;) {
switch (yytoken) {
case '(': dp = fundcl(dp); break;
case '[': dp = arydcl(dp); break;
default: return dp;
}
}
}
static struct dcldata*
declarator0(struct dcldata *dp, uint8_t ns)
{
uint8_t n;
for (n = 0; accept('*'); ++n) {
while (accept(TQUALIFIER))
/* nothing */;
}
dp = directdcl(dp, ns);
while (n--)
dp = queue(dp, PTR, 0, NULL);
return dp;
}
static Symbol *
declarator(Type *tp, int8_t flags, uint8_t ns)
{
struct dcldata data[NR_DECLARATORS+2];
struct dcldata *bp;
Symbol *sym;
memset(data, 0, sizeof(data));
data[NR_DECLARATORS].op = 255;
for (bp = declarator0(data, ns)-1; bp >= data; --bp) {
if (bp->op != IDEN) {
tp = mktype(tp, bp->op, bp->nelem, bp->data);
} else {
sym = bp->data;
if (flags == ID_EXPECTED && *sym->name == '\0')
error("missed identifier in declaration");
if (flags == ID_FORBIDDEN && *sym->name != '\0')
error("unexpected identifier in type name");
break;
}
}
/* TODO: deal with external array declarations of [] */
if (!tp->defined && *sym->name)
error("declared variable '%s' of incomplete type", sym->name);
sym->type = tp;
return sym;
}
static Type *structdcl(void), *enumdcl(void);
static Type *
specifier(int8_t *sclass)
{
Type *tp = NULL;
int8_t qlf, sign, type, cls, size, t;
qlf = sign = type = cls = size = 0;
for (;;) {
int8_t *p;
Type *(*dcl)(void) = NULL;
switch (yytoken) {
case SCLASS: p = &cls; break;
case TQUALIFIER:
if ((qlf |= yylval.token) & RESTRICT)
goto invalid_type;
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) {
size = LONG+LONG;
break;
}
case SHORT:
p = &size; break;
}
break;
default:
goto return_type;
}
if (*p)
goto invalid_type;
*p = yylval.token;
if (dcl) {
if (size || sign)
goto invalid_type;
tp = (*dcl)();
} else {
next();
}
}
return_type:
if (sclass)
*sclass = cls;
if (!tp)
tp = ctype(type, sign, size);
return tp;
invalid_type:
error("invalid type specification");
}
/* TODO: check correctness of the initializator */
/* TODO: emit initializer */
static struct node *
initializer(Symbol *sym)
{
if (!sym->isdefined)
error("'%s' initialized and declared extern", sym->name);
if (accept('{')) {
initializer(sym);
expect('}');
} else {
do {
expr();
} while (accept(','));
}
return NULL;
}
static Symbol *
newtag(uint8_t tag)
{
Symbol *sym;
static uint8_t ns = NS_STRUCTS;
switch (yytoken) {
case IDEN: case TYPEIDEN:
if ((sym = lookup(yytext, NS_TAG)) == NULL)
sym = install(yytext, NS_TAG);
next();
break;
default:
sym = install("", NS_TAG);
break;
}
if (!sym->type) {
if (ns == NS_STRUCTS + NR_MAXSTRUCTS)
error("too much tags declared");
sym->type = mktype(NULL, tag, 0, NULL);
sym->type->ns = ns++;
}
if (sym->type->op != tag)
error("'%s' defined as wrong kind of tag", yytext);
return sym;
}
/* TODO: bitfields */
static Type *
structdcl(void)
{
Type *tagtype, *buff[NR_MAXSTRUCTS], **bp = &buff[0];
Symbol *tagsym, *sym;
uint8_t tag, n;
size_t siz;
tag = yylval.token;
next();
tagsym = newtag(tag);
tagtype = tagsym->type;
if (!accept('{'))
return tagtype;
if (tagtype->defined)
error("redefinition of struct/union '%s'", yytext);
tagtype->defined = 1;
emitstruct(tagsym);
while (!accept('}')) {
Type *base, *tp;
switch (yytoken) {
case SCLASS:
error("storage class '%s' in struct/union field",
yytext);
case IDEN: case TYPE: case TYPEIDEN: case TQUALIFIER:
base = specifier(NULL);
break;
case ';':
next();
continue;
default:
unexpected();
}
if (accept(';'))
error("identifier expected");
do {
sym = declarator(base, ID_EXPECTED, tagtype->ns);
sym->isfield = 1;
tp = sym->type;
if (tp->op == FTN)
error("invalid type in struct/union");
if (bp == &buff[NR_MAXSTRUCTS])
error("too much fields in struct/union");
*bp++ = sym->type;
emitdcl(sym);
} while (accept(','));
expect(';');
}
emitestruct();
if ((n = bp - buff) != 0) {
siz = sizeof(Type *) * n;
tagtype->n.elem = n;
tagtype->pars = memcpy(xmalloc(siz), buff, siz);
}
return tagtype;
}
static Type *
enumdcl(void)
{
Type *tp;
Symbol *sym;
int val = 0;
next();
tp = newtag(ENUM)->type;
if (yytoken == ';')
return tp;
expect('{');
if (tp->defined)
error("redefinition of enumeration '%s'", yytext);
tp->defined = 1;
while (yytoken != '}') {
if (yytoken != IDEN)
unexpected();
sym = newiden(NS_IDEN);
sym->type = inttype;
if (accept('='))
initializer(sym);
sym->u.i = val++;
if (!accept(','))
break;
}
expect('}');
return tp;
}
static Symbol *
parameter(void)
{
Symbol *sym;
int8_t sclass;
Type *tp;
if ((tp = specifier(&sclass)) == voidtype)
return NULL;
sym = declarator(tp, ID_ACCEPTED, NS_IDEN);
sym->isparameter = 1;
tp = sym->type;
if (tp->op == FTN)
error("incorrect function type for a function parameter");
if (tp->op == ARY)
tp = mktype(tp->type, PTR, 0, NULL);
switch (sclass) {
case REGISTER:
sym->isregister = 1;
break;
case 0:
sym->isauto = 1;
break;
default:
error("bad storage class in function parameter");
}
return sym;
}
void
decl(void)
{
Type *tp;
Symbol *sym;
int8_t sclass, isfun;
tp = specifier(&sclass);
if (accept(';'))
return;
do {
sym = declarator(tp, ID_EXPECTED, NS_IDEN);
isfun = sym->type->op == FTN;
switch (sclass) {
case TYPEDEF:
sym->token = TYPEIDEN;
continue;
case STATIC:
sym->isstatic = 1;
break;
case EXTERN:
sym->isdefined = 0;
break;
case REGISTER:
sym->isregister = 1;
if (isfun)
goto bad_function;
break;
case AUTO:
if (isfun)
goto bad_function;
/* passtrough */
default:
sym->isauto = 1;
break;
}
if (accept('='))
initializer(sym);
emitdcl(sym);
} while (accept(','));
expect(';');
return;
bad_function:
error("invalid storage class for function '%s'", sym->name);
}
Type *
typename(void)
{
int8_t sclass;
Type *tp;
Symbol *sym;
tp = specifier(&sclass);
if (sclass)
error("class storage in type name");
sym = declarator(tp, ID_FORBIDDEN, NS_IDEN);
return sym->type;
}
void
extdecl(void)
{
Type *base, *tp;
int8_t sclass;
Symbol *sym;
extern Symbol *curfun;
switch (yytoken) {
case IDEN: case TYPE: case TYPEIDEN: case SCLASS: case TQUALIFIER:
base = specifier(&sclass);
if (accept(';'))
return;
do {
sym = declarator(base, ID_EXPECTED, NS_IDEN);
tp = sym->type;
sym->isstatic = 1;
sym->isglobal= 1;
switch (sclass) {
case REGISTER: case AUTO:
error("incorrect storage class for file-scope declaration");
case STATIC:
sym->isglobal = 0;
break;
case EXTERN:
sym->isdefined = 0;
break;
case TYPEDEF:
sym->token = TYPEIDEN;
continue;
}
if (tp->op != FTN) {
if (accept('='))
initializer(sym);
emitdcl(sym);
} else if (yytoken == '{') {
curfun = sym;
emitfun(sym);
compound(NULL, NULL, NULL);
emitefun();
popctx();
return;
}
} while (accept(','));
/* PASSTHROUGH */
case ';':
expect(';');
return;
default:
unexpected();
}
}