ref: fdbaed739f4eb78f65514764b87fb87834b76ed3
dir: /decl.c/
#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include "sizes.h"
#include "cc.h"
#include "tokens.h"
#include "syntax.h"
#include "symbol.h"
#include "machine.h"
#define ID_EXPECTED 1
#define ID_ACCEPTED 2
int8_t forbid_eof;
struct dcldata {
uint8_t op;
union {
unsigned short nelem;
struct symbol *sym;
struct funpars *pars;
uint8_t qlf;
} u;
};
static struct dcldata
*declarator0(struct dcldata *dp, uint8_t ns, int8_t flags);
static struct dcldata *
arydcl(struct dcldata *dp)
{
expect('[');
expect(']');
if (dp->op == 255)
error("too much declarators");
dp->u.nelem = 0;
dp->op = ARY;
return dp + 1;
}
static struct dcldata *
fundcl(struct dcldata *dp)
{
expect('(');
expect(')');;
if (dp->op == 255)
error("too much declarators");
dp->op = FTN;
dp->u.pars = NULL;
return dp + 1;
}
static struct symbol *
newiden(uint8_t ns)
{
struct symbol *sym;
if ((sym = lookup(yytext, ns)) && sym->ctx == curctx)
error("redeclaration of '%s'", yytext);
sym = install(yytext, ns);
next();
return sym;
}
static struct dcldata *
directdcl(struct dcldata *dp, uint8_t ns, int8_t flags)
{
register struct symbol *sym;
char *err;
if (accept('(')) {
dp = declarator0(dp, ns, flags);
expect(')');
} else if (flags) {
if (yytoken != IDEN) {
if (flags & ID_EXPECTED)
goto expected;
sym = install(NULL, ns);
} else {
sym = newiden(ns);
}
dp->op = IDEN;
dp->u.sym = sym;
++dp;
}
for (;;) {
switch (yytoken) {
case '(': dp = fundcl(dp); break;
case '[': dp = arydcl(dp); break;
default: return dp;
}
}
expected:
error("expected '(' or identifier before of '%s'" , yytext);
}
static struct dcldata*
declarator0(struct dcldata *dp, uint8_t ns, int8_t flags)
{
uint8_t buffer[NR_DECLARATORS];
register uint8_t *bp, n, qlf;
bp = buffer;
for (n = 0; accept('*'); ++n) {
if (n == NR_DECLARATORS)
goto too_much_declarators;
qlf = 0;
if (yytoken == TQUALIFIER) {
qlf |= yylval.sym->u.c;
next();
}
*bp++ = qlf;
}
dp = directdcl(dp, ns, flags);
bp = buffer;
while (n--) {
if (dp->op == 255)
goto too_much_declarators;
dp->op = PTR;
dp->u.qlf = *bp++;
++dp;
}
return dp;
too_much_declarators:
error("too much declarators");
}
static struct symbol *
declarator(struct ctype *tp, uint8_t ns, int8_t flags)
{
struct dcldata data[NR_DECLARATORS+1];
register struct dcldata *bp;
struct symbol *sym;
data[NR_DECLARATORS].op = 255;
for (bp = declarator0(data, ns, flags); bp >= data; --bp) {
switch (bp->op) {
case PTR:
tp = qualifier(mktype(tp, PTR, NULL, 0), bp->u.qlf);
break;
case ARY:
tp = mktype(tp, ARY, NULL, bp->u.nelem);
break;
case FTN:
tp = mktype(tp, FTN, NULL, 0);
break;
case IDEN:
sym = bp->u.sym;
break;
}
}
sym->type = tp;
return sym;
}
static struct ctype *structdcl(uint8_t tag), *enumdcl(uint8_t tag);
static struct ctype *
specifier(int8_t *sclass)
{
struct ctype *tp = NULL;
int8_t qlf, sign, type, cls, cplex, size, t;
qlf = sign = type = cls = size = cplex = 0;
for (;;) {
register uint8_t *p;
struct symbol *sym = yylval.sym;
switch (yytoken) {
case SCLASS: p = &cls; break;
case TQUALIFIER:
if ((qlf |= sym->u.c) & RESTRICT)
goto invalid_type;
goto next_token;
case TYPE:
switch (t = sym->u.c) {
case ENUM: case STRUCT: case UNION:
next();
tp = (t == ENUM) ? enumdcl(t) : structdcl(t);
p = &type;
goto check_spec;
case TYPENAME:
tp = yylval.sym->type;
case VOID: case BOOL: case CHAR:
case INT: case FLOAT: case DOUBLE:
p = &type; goto next_token;
case SIGNED: case UNSIGNED:
p = &sign; break;
case LONG:
if (size == LONG) {
size = LONG+LONG;
goto next_token;
}
case SHORT:
p = &size; goto next_token;
case COMPLEX: case IMAGINARY:
p = &cplex; goto next_token;
}
break;
default:
goto check_types;
}
next_token: next();
check_spec: if (*p)
goto invalid_type;
*p = sym->u.c;
}
check_types:
if (!type) {
if (!sign && !size) {
warn(options.implicit,
"type defaults to 'int' in declaration");
}
type = INT;
}
if (sign && type != INT && type != CHAR ||
cplex && type != FLOAT && type != DOUBLE ||
size == SHORT && type != INT ||
size == LONG && type != INT && type != DOUBLE ||
size == LONG+LONG && type != INT) {
goto invalid_type;
}
if (sclass)
*sclass = cls;
if (!tp)
tp = ctype(type, sign, size, cplex);
return (qlf) ? qualifier(tp, qlf) : tp;
invalid_type:
error("invalid type specification");
}
static struct node *
initializer(register struct ctype *tp)
{
if (accept('{')) {
initializer(tp);
expect('}');
} else {
do {
expr();
} while (accept(','));
}
}
/* TODO: bitfields */
static void
newfield(struct ctype *tp, struct symbol *sym)
{
register struct field *p, *q;
register char *s, *t;
static short size, offset;
static uint8_t op;
static char *err;
s = sym->name;
op = tp->op;
for (q = p = tp->u.fields; p; q = p, p = p->next) {
t = p->sym->name;
if (*s == *t && !strcmp(s, t))
goto duplicated_name;
if (op == ENUM && sym->u.i == p->sym->u.i)
goto duplicated_value;
}
p = xmalloc(sizeof(*p));
p->next = NULL;
p->sym = sym;
size = sym->type->size;
if (!q) {
tp->u.fields = p;
if (op != ENUM) {
tp->size = size;
sym->u.offset = 0;
}
} else {
q->next = p;
if (tp->op == STRUCT) {
offset = ALIGN(size, tp->size);
sym->u.offset = offset;
tp->size = offset + size;
} else if (op == UNION) {
sym->u.offset = 0;
if (tp->size < size)
tp->size = size;
}
}
return;
duplicated_name:
err = "duplicated fields '%s' and '%s'";
goto error;
duplicated_value:
err = "duplicated enumeration fields '%s' and '%s'";
error: error(err, s, t);
}
static void
fielddcl(struct ctype *base, uint8_t ns)
{
struct ctype *tp;
struct symbol *sym;
switch (yytoken) {
case SCLASS:
error("storage class '%s' in struct/union field", yytext);
case IDEN: case TYPE: case TQUALIFIER:
tp = specifier(NULL);
break;
case ';':
break;
default:
error("declaration expected");
}
if (yytoken != ';') {
do {
sym = declarator(tp, ns, ID_EXPECTED);
newfield(tp, sym);
} while (accept(','));
}
expect(';');
}
static struct ctype *
newtag(uint8_t tag)
{
register struct symbol *sym;
struct ctype *tp;
extern uint8_t namespace;
if (yytoken == IDEN) {
sym = lookup(yytext, NS_TAG);
if (sym) {
if (sym->type->op != tag)
goto bad_tag;
} else {
sym = install(yytext, NS_TAG);
}
next();
} else {
sym = install(NULL, NS_TAG);
}
tp = sym->type = mktype(NULL, tag, NULL, 0);
sym->u.ns = ++namespace;
tp->sym = sym;
return tp;
bad_tag:
error("'%s' defined as wrong kind of tag", yytext);
}
static struct ctype *
structdcl(uint8_t tag)
{
struct ctype *tp;
uint8_t ns;
tp = newtag(tag);
tp->u.fields = NULL;
ns = tp->sym->u.ns;
if (yytoken != ';') {
expect('{');
if (tp->defined)
goto redefined;
tp->defined = 1;
while (!accept('}'))
fielddcl(tp, ns);
}
return tp;
redefined:
error("redefinition of struct/union '%s'", yytext);
}
static struct ctype *
enumdcl(uint8_t token)
{
register struct ctype *tp;
struct symbol *sym;
int val = 0;
char *err;
tp = newtag(ENUM);
if (yytoken != ';') {
expect('{');
if (tp->defined)
goto redefined;
tp->defined = 1;
while (yytoken != '}') {
if (yytoken != IDEN)
goto iden_expected;
sym = newiden(NS_IDEN);
sym->type = inttype;
if (accept('='))
initializer(inttype);
sym->u.i = val++;
newfield(tp, sym);
if (!accept(','))
break;
}
expect('}');
}
return tp;
redefined:
err = "redefinition of enumeration '%s'";
goto error;
iden_expected:
err = "identifier expected";
error: error(err, yytext);
}
struct node *
decl(void)
{
struct ctype *tp;
struct symbol *sym;
int8_t sclass;
tp = specifier(&sclass);
if (yytoken != ';') {
do {
sym = declarator(tp, NS_IDEN, ID_EXPECTED);
/* assign storage class */
if (accept('='))
initializer(sym->type);
} while (accept(','));
}
expect(';');
return NULL;
}
struct node *
typename(void)
{
declarator(specifier(NULL), NS_IDEN, 0);
return NULL;
}
struct node *
extdecl(void)
{
struct ctype *tp;
int8_t sclass;
struct symbol *sym;
extern struct symbol *curfun;
char *err;
forbid_eof = 1;
switch (yytoken) {
case IDEN: TYPE: case SCLASS: case TQUALIFIER:
tp = specifier(&sclass);
if (sclass == REGISTER || sclass == AUTO)
goto bad_storage;
case ';':
break;
default:
goto dcl_expected;
}
if (yytoken != ';') {
do {
extern void printtype(struct ctype *tp);
sym = declarator(tp, NS_IDEN, ID_EXPECTED);
printtype(sym->type);
/* assign storage class */
if (isfun(sym)) {
if (yytoken == '{') {
curfun = sym;
context(function);
freesyms(NS_LABEL);
}
} else if (accept('=')) {
initializer(sym->type);
}
} while (accept(','));
}
forbid_eof = 0;
expect(';');
return NULL;
bad_storage:
err = "incorrect storage class for file-scope declaration";
goto error;
dcl_expected:
err = "declaration expected";
error: error(err);
}