ref: 3264efeca8c41b909a8fca2c57785f936fb55f80
dir: /src/cmd/cc/cc1/decl.c/
#include <assert.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <scc/cstd.h>
#include <scc/scc.h>
#include "cc1.h"
#define NOSCLASS 0
#define NOREP 0
#define REP 1
#define QUIET 1
#define NOQUIET 0
#define NR_DCL_TYP (NR_DECLARATORS+NR_FUNPARAM)
#define NR_DCL_SYM (NR_DECLARATORS+NR_FUNPARAM+1)
struct declarators {
unsigned nr;
unsigned ns;
struct decl *dcl;
unsigned nr_types;
Type **tpars;
Symbol **pars;
struct declarator {
unsigned char op;
TINT nelem;
Symbol *sym;
Type **tpars;
Symbol **pars;
} d [NR_DECLARATORS];
};
struct decl {
unsigned ns;
int sclass;
int qualifier;
Symbol *sym;
Type *type;
Type *parent;
Symbol **pars;
Symbol *bufpars[NR_DCL_SYM];
Type *buftpars[NR_DCL_TYP];
};
static void
endfundcl(Type *tp, Symbol **pars)
{
/*
* If endfundcl is called from a type built from a typedef then
* we do not have any parameters because in that case we only
* care about the type.
*/
if (pars) {
if ((tp->prop&TK_R) != 0 && *pars)
warn("parameter names (without types) in function declaration");
/* avoid non used warnings in prototypes */
while (*pars)
(*pars++)->flags |= SUSED;
popctx();
}
}
static void
push(struct declarators *dp, int op, ...)
{
va_list va;
unsigned n;
struct declarator *p;
va_start(va, op);
if ((n = dp->nr++) == NR_DECLARATORS)
error("too many declarators");
p = &dp->d[n];
p->op = op;
p->tpars = NULL;
switch (op) {
case ARY:
p->nelem = va_arg(va, TINT);
break;
case KRFTN:
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 int
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;
}
/*
* We have a type derived from a function type. We don't care
* about the parameters because they were used only in the
* process of building a final type. Prototype arguments are
* discarded in funbody() because the final type of the decl
* is an actual function.
*/
if (dcl->type->op == FTN)
endfundcl(dcl->type, dcl->pars);
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 = 0;
int ns;
ns = namespace;
namespace = NS_IDEN;
expect('[');
if (yytoken != ']') {
if ((np = constexpr()) == NULL) {
errorp("invalid storage size");
} else {
if ((n = np->sym->u.i) <= 0) {
errorp("array size is not a positive number");
n = 1;
}
freetree(np);
}
}
namespace = ns;
expect(']');
push(dp, ARY, n);
}
static int
empty(Symbol *sym, Type *tp, int param)
{
if (!sym->name) {
sym->type = tp;
switch (tp->op) {
default:
/* warn if it is not a parameter */
if (!param)
warn("empty declaration");
case STRUCT:
case UNION:
case ENUM:
return 1;
}
}
return 0;
}
static void
bad_storage(Type *tp, char *name)
{
if (tp->op != FTN)
errorp("incorrect storage class for file-scope declaration");
else
errorp("invalid storage class for function '%s'", name);
}
static Symbol *
redcl(Symbol *sym, Type *tp, int sclass)
{
int flags;
char *name = sym->name;
if (sym->type->op == FTN && tp->op == FTN) {
Type *ntp = sym->type;
if (eqtype(ntp->type, tp->type, 1)) {
if (tp->prop & TK_R)
tp = ntp;
if (sym->type->prop & TK_R)
sym->type = tp;
}
}
if (!eqtype(sym->type, tp, 1)) {
errorp("conflicting types for '%s'", name);
return sym;
}
if (sym->token == TYPEIDEN && sclass != TYPEDEF ||
sym->token != TYPEIDEN && sclass == TYPEDEF) {
goto redeclaration;
}
if (curctx != GLOBALCTX && tp->op != FTN) {
/* is it the redeclaration of a local variable? */
if ((sym->flags & SEXTERN) && sclass == EXTERN)
return sym;
goto redeclaration;
}
flags = sym->flags;
switch (sclass) {
case REGISTER:
case AUTO:
bad_storage(tp, name);
break;
case NOSCLASS:
if ((flags & SPRIVATE) == 0) {
if (flags & SEXTERN)
flags &= ~(SEXTERN|SEMITTED);
flags |= SGLOBAL;
break;
}
errorp("non-static declaration of '%s' follows static declaration",
name);
break;
case TYPEDEF:
/* Only C11 allows multiple definitions of a typedef. */
goto redeclaration;
case EXTERN:
break;
case STATIC:
if ((flags & (SGLOBAL|SEXTERN)) == 0) {
flags |= SPRIVATE;
break;
}
errorp("static declaration of '%s' follows non-static declaration",
name);
break;
}
sym->flags = flags;
return sym;
redeclaration:
errorp("redeclaration of '%s'", name);
return sym;
}
static Symbol *
identifier(struct decl *dcl)
{
Symbol *sym = dcl->sym;
Type *tp = dcl->type;
int sclass = dcl->sclass;
char *name = sym->name;
if (empty(sym, tp, 0))
return sym;
/* TODO: Add warning about ANSI limits */
if (!(tp->prop & TDEFINED) &&
sclass != EXTERN && sclass != TYPEDEF &&
!(tp->op == ARY && yytoken == '=')) {
errorp("declared variable '%s' of incomplete type", name);
}
if (tp->op == FTN) {
if (sclass == NOSCLASS)
sclass = EXTERN;
if (!strcmp(name, "main") && tp->type != inttype) {
errorp("main shall be defined with a return type of int");
errorp("please contact __20h__ on irc.bitreich.org (#bitreich-en) via IRC");
}
}
if (sym->flags & SDECLARED) {
sym = redcl(dcl->sym, tp, sclass);
} else {
int flags = sym->flags | SDECLARED;
sym->type = tp;
switch (sclass) {
case REGISTER:
case AUTO:
if (curctx != GLOBALCTX && tp->op != FTN) {
flags |= (sclass == REGISTER) ? SREGISTER : SAUTO;
break;
}
bad_storage(tp, name);
case NOSCLASS:
if (tp->op == FTN)
flags |= SEXTERN;
else
flags |= (curctx == GLOBALCTX) ? SGLOBAL : SAUTO;
break;
case EXTERN:
flags |= SEXTERN;
break;
case STATIC:
flags |= (curctx == GLOBALCTX) ? SPRIVATE : SLOCAL;
break;
case TYPEDEF:
flags |= STYPEDEF;
sym->u.token = sym->token = TYPEIDEN;
break;
}
sym->flags = flags;
}
if (accept('='))
initializer(sym, sym->type);
if (!(sym->flags & (SGLOBAL|SEXTERN)) && tp->op != FTN)
sym->flags |= SDEFINED;
if (sym->token == IDEN && tp->op != FTN)
emit(ODECL, sym);
return sym;
}
static Symbol *
parameter(struct decl *dcl)
{
Symbol *sym = dcl->sym;
Type *funtp = dcl->parent, *tp = dcl->type;
char *name = sym->name;
int flags;
flags = 0;
switch (dcl->sclass) {
case STATIC:
case EXTERN:
case AUTO:
errorp("bad storage class in function parameter");
break;
case REGISTER:
flags |= SREGISTER;
break;
case NOSCLASS:
flags |= SAUTO;
break;
}
switch (tp->op) {
case VOID:
funtp->n.elem = 1;
if (dcl->sclass)
errorp("void as unique parameter may not be qualified");
return NULL;
case ARY:
tp = mktype(tp->type, PTR, 0, NULL);
break;
case FTN:
errorp("incorrect function type for a function parameter");
return NULL;
}
if (!empty(sym, tp, 1)) {
int isdcl = sym->flags&SDECLARED, isk_r = funtp->prop & TK_R;
if (isdcl && !isk_r) {
errorp("redefinition of parameter '%s'", name);
return NULL;
}
if (!isdcl && isk_r) {
errorp("declaration for parameter '%s' but no such parameter",
sym->name);
return NULL;
}
sym->flags |= SDECLARED;
}
sym->type = tp;
sym->flags &= ~(SAUTO|SREGISTER);
sym->flags |= flags;
return sym;
}
static Symbol *dodcl(int rep,
Symbol *(*fun)(struct decl *),
unsigned ns,
Type *type);
static int
krpars(struct declarators *dp)
{
Symbol *sym;
int toomany = 0;
unsigned npars = 0;
do {
sym = yylval.sym;
expect(IDEN);
sym->flags |= SAUTO;
if ((sym = install(NS_IDEN, sym)) == NULL) {
errorp("redefinition of parameter '%s'",
yylval.sym->name);
continue;
}
if (npars < NR_FUNPARAM) {
++npars;
*dp->pars++ = sym;
continue;
}
if (!toomany)
toomany = 1;
} while (accept(','));
return toomany;
}
static unsigned
krfun(struct declarators *dp)
{
int toomany = 0;
if (yytoken != ')')
toomany = krpars(dp);
if (dp->nr_types == NR_DCL_TYP) {
toomany = 1;
} else {
++dp->nr_types;
*dp->tpars++ = ellipsistype;
}
if (toomany)
errorp("too many parameters in function definition");
return 1;
}
static unsigned
ansifun(struct declarators *dp)
{
Symbol *sym;
unsigned npars, ntype, toomany, distoomany, voidpar;
Type type, *tp;
type.n.elem = 0;
type.prop = 0;
npars = ntype = toomany = distoomany = voidpar = 0;
do {
if (accept(ELLIPSIS)) {
if (ntype < 1)
errorp("a named argument is requiered before '...'");
if (yytoken != ')')
errorp("... must be the last parameter");
sym = NULL;
tp = ellipsistype;
} else if ((sym = dodcl(NOREP, parameter, NS_IDEN, &type)) == NULL) {
if (type.n.elem == 1 && ntype > 1)
voidpar = 1;
sym = NULL;
tp = NULL;
} else {
tp = sym->type;
}
if (sym) {
if (npars == NR_FUNPARAM) {
toomany = 1;
} else {
npars++;
*dp->pars++ = sym;
}
}
if (tp) {
if (dp->nr_types == NR_DCL_TYP) {
toomany = 1;
} else {
ntype++;
dp->nr_types++;
*dp->tpars++ = tp;
}
}
} while (accept(','));
if (toomany == 1)
errorp("too many parameters in function definition");
if (voidpar && ntype > 1)
errorp("'void' must be the only parameter");
return ntype;
}
static int
funbody(Symbol *sym, Symbol *pars[])
{
Type *tp;
Symbol **bp, *p;
if (!sym)
return 0;
tp = sym->type;
if (tp->op != FTN)
return 0;
switch (yytoken) {
case '{':
case TYPE:
case SCLASS:
case TYPEIDEN:
if (curctx < PARAMCTX) {
assert(!pars);
errorp("typedef'ed function type cannot be instantiated");
curctx = PARAMCTX;
pars = (Symbol *[]) {NULL};
}
if (curctx != PARAMCTX)
errorp("nested function declaration");
if (sym && sym->ns == NS_IDEN)
break;
default:
emit(ODECL, sym);
endfundcl(tp, pars);
return 0;
}
tp->prop |= TFUNDEF;
curfun = sym;
if (sym->type->prop & TK_R) {
while (yytoken != '{') {
dodcl(REP, parameter, NS_IDEN, sym->type);
expect(';');
}
for (bp = pars; p = *bp; ++bp) {
if (p->type == NULL) {
warn("type of '%s' defaults to int", p->name);
p->type = inttype;
}
}
}
if (sym->flags & STYPEDEF)
errorp("function definition declared 'typedef'");
if (sym->flags & SDEFINED)
errorp("redefinition of '%s'", sym->name);
if (sym->flags & SEXTERN) {
sym->flags &= ~SEXTERN;
sym->flags |= SGLOBAL;
}
sym->flags |= SDEFINED;
sym->flags &= ~SEMITTED;
sym->u.pars = pars;
emit(OFUN, sym);
compound(NULL, NULL, NULL);
emit(OEFUN, NULL);
popctx();
flushtypes();
curfun = NULL;
return 1;
}
static void
fundcl(struct declarators *dp)
{
Type **types = dp->tpars;
unsigned ntypes, typefun;
Symbol **pars = dp->pars;
unsigned (*fun)(struct declarators *);
pushctx();
expect('(');
if (yytoken == ')' || yytoken == IDEN) {
typefun = KRFTN;
fun = krfun;
} else {
typefun = FTN;
fun = ansifun;
}
ntypes = (*fun)(dp);
*dp->pars++= NULL;
expect(')');
push(dp, typefun, ntypes, types, pars);
}
static void declarator(struct declarators *dp);
static void
directdcl(struct declarators *dp)
{
Symbol *p, *sym;
static int nested;
if (accept('(')) {
if (nested == NR_SUBTYPE)
error("too many declarators nested by parentheses");
++nested;
declarator(dp);
--nested;
expect(')');
} else {
if (yytoken == IDEN || yytoken == TYPEIDEN) {
sym = yylval.sym;
if (p = install(dp->ns, sym)) {
sym = p;
sym->flags &= ~SDECLARED;
}
next();
} else {
sym = newsym(dp->ns, NULL);
}
push(dp, IDEN, sym);
}
for (;;) {
switch (yytoken) {
case '(': fundcl(dp); break;
case '[': arydcl(dp); break;
default: return;
}
}
}
static void
declarator(struct declarators *dp)
{
unsigned n;
for (n = 0; accept('*'); ++n) {
while (accept(TQUALIFIER))
;
}
directdcl(dp);
while (n--)
push(dp, PTR);
}
static Type *structdcl(void), *enumdcl(void);
static Type *
specifier(int *sclass, int *qualifier)
{
Type *tp = NULL;
unsigned spec, qlf, sign, type, cls, size;
spec = qlf = sign = type = cls = size = 0;
for (;;) {
unsigned *p = NULL;
Type *(*dcl)(void) = NULL;
switch (yytoken) {
case SCLASS:
p = &cls;
break;
case TQUALIFIER:
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 VA_LIST:
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;
}
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:
*sclass = cls;
*qualifier = qlf;
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;
}
static Symbol *
newtag(void)
{
Symbol *sym;
int ns, op, tag = yylval.token;
static unsigned tpns = NS_STRUCTS;
ns = namespace;
namespace = NS_TAG;
next();
namespace = ns;
switch (yytoken) {
case IDEN:
case TYPEIDEN:
sym = yylval.sym;
if ((sym->flags & SDECLARED) == 0)
install(NS_TAG, yylval.sym);
next();
break;
default:
sym = newsym(NS_TAG, NULL);
break;
}
if (!sym->type) {
Type *tp;
if (tpns == NS_STRUCTS + NR_MAXSTRUCTS)
error("too many tags declared");
tp = mktype(NULL, tag, 0, NULL);
tp->ns = tpns++;
sym->type = tp;
tp->tag = sym;
DBG("DECL: declared tag '%s' with ns = %d\n",
(sym->name) ? sym->name : "anonymous", tp->ns);
}
if ((op = sym->type->op) != tag && op != INT)
error("'%s' defined as wrong kind of tag", sym->name);
return sym;
}
static void fieldlist(Type *tp);
static Type *
structdcl(void)
{
Symbol *sym;
Type *tp;
static int nested;
int ns;
sym = newtag();
tp = sym->type;
if (!accept('{'))
return tp;
ns = namespace;
namespace = tp->ns;
if (tp->prop & TDEFINED && sym->ctx == curctx)
error("redefinition of struct/union '%s'", sym->name);
if (nested == NR_STRUCT_LEVEL)
error("too many levels of nested structure or union definitions");
++nested;
while (yytoken != '}')
fieldlist(tp);
--nested;
deftype(tp);
namespace = ns;
expect('}');
return tp;
}
static Type *
enumdcl(void)
{
Type *tp;
Symbol *sym, *tagsym;
int ns, val, toomany;
unsigned nctes;
ns = namespace;
tagsym = newtag();
tp = tagsym->type;
namespace = NS_IDEN;
if (!accept('{'))
goto restore_name;
if (tp->prop & TDEFINED)
errorp("redefinition of enumeration '%s'", tagsym->name);
deftype(tp);
/* TODO: check incorrect values in val */
for (nctes = val = 0; yytoken != '}'; ++nctes, ++val) {
if (yytoken != IDEN)
unexpected();
sym = yylval.sym;
next();
if (nctes == NR_ENUM_CTES && !toomany) {
errorp("too many enum constants in a single enum");
toomany = 1;
}
if (accept('=')) {
Node *np = constexpr();
if (np == NULL)
errorp("invalid enumeration value");
else
val = np->sym->u.i;
freetree(np);
}
if ((sym = install(NS_IDEN, sym)) == NULL) {
errorp("'%s' redeclared as different kind of symbol",
yytext);
} else {
sym->u.i = val;
sym->flags |= SCONSTANT;
sym->type = inttype;
}
if (!accept(','))
break;
}
expect('}');
restore_name:
namespace = ns;
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)
{
static char *anon = "<anonymous>";
Symbol *sym = dcl->sym;
char *name = (sym->name) ? sym->name : anon;
Type *structp = dcl->parent, *tp = dcl->type;
TINT n = structp->n.elem;
if (accept(':')) {
Node *np;
TINT n;
if ((np = constexpr()) == NULL) {
unexpected();
n = 0;
} else {
n = np->sym->u.i;
freetree(np);
}
if (n == 0 && name != anon)
errorp("zero width for bit-field '%s'", name);
if (tp != booltype && tp != inttype && tp != uinttype)
errorp("bit-field '%s' has invalid type", name);
if (n < 0)
errorp("negative width in bit-field '%s'", name);
else if (n > tp->size*8)
errorp("width of '%s' exceeds its type", name);
} else if (empty(sym, tp, 0)) {
return sym;
}
if (sym->flags & SDECLARED) {
errorp("duplicated member '%s'", name);
return sym;
}
if ((tp->prop & TDEFINED) == 0) {
errorp("field '%s' has incomplete type", name);
tp = inttype;
}
if (tp->op == FTN) {
errorp("field '%s' declared as a function", name);
tp = inttype;
}
if (dcl->sclass)
errorp("storage class in struct/union field '%s'", name);
sym->type = tp;
sym->flags |= SFIELD|SDECLARED;
if (n == NR_FIELDS) {
errorp("too many fields in struct/union");
return sym;
}
DBG("DECL: New field '%s' in namespace %d\n", name, structp->ns);
structp->p.fields = xrealloc(structp->p.fields, ++n * sizeof(*sym));
structp->p.fields[n-1] = sym;
structp->n.elem = n;
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, &dcl.qualifier);
do {
dcl.type = base;
dcl.pars = NULL;
stack.nr_types = stack.nr = 0;
stack.tpars = dcl.buftpars;
stack.pars = dcl.bufpars;
stack.dcl = &dcl;
stack.ns = ns;
declarator(&stack);
while (pop(&stack, &dcl))
;
sym = (*fun)(&dcl);
if (funbody(sym, dcl.pars))
return sym;
} while (rep && accept(','));
return sym;
}
void
decl(void)
{
Symbol *sym;
if (accept(';'))
return;
sym = dodcl(REP, identifier, NS_IDEN, NULL);
if (sym->type->prop & TFUNDEF)
return;
expect(';');
}
static void
fieldlist(Type *tp)
{
if (yytoken != ';')
dodcl(REP, field, tp->ns, tp);
expect(';');
}
Type *
typename(void)
{
return dodcl(NOREP, type, NS_DUMMY, NULL)->type;
}