view dmd/enum.c @ 1317:4099548c80e0

Allocate objects on the stack if they (a) don't have a destructor, and (b) don't override the delete operator (on top of the regular conditions for stack allocation that also apply to arrays, structs, etc.). The "no destructor" clause is not strictly necessary, but calling them at the right time would be tricky to say the least; it would involve, among other things, "manually" inserting a try-finally block around anything that might throw exceptions not caught in the current function. Note: objects with custom new operators are automatically ignored because they don't use the regular allocation runtime call, so there's no need to pay special attention to them.
author Frits van Bommel <fvbommel wxs.nl>
date Sat, 09 May 2009 00:50:15 +0200
parents e961851fb8be
children 1b24e9c7cc26
line wrap: on
line source


// Copyright (c) 1999-2009 by Digital Mars
// All Rights Reserved
// written by Walter Bright
// http://www.digitalmars.com
// License for redistribution is by either the Artistic License
// in artistic.txt, or the GNU General Public License in gnu.txt.
// See the included readme.txt for details.

#include <stdio.h>
#include <assert.h>

#include "root.h"
#include "enum.h"
#include "mtype.h"
#include "scope.h"
#include "declaration.h"

/********************************* EnumDeclaration ****************************/

EnumDeclaration::EnumDeclaration(Loc loc, Identifier *id, Type *memtype)
    : ScopeDsymbol(id)
{
    this->loc = loc;
    type = new TypeEnum(this);
    this->memtype = memtype;
    maxval = 0;
    minval = 0;
    defaultval = 0;
#if IN_DMD
    sinit = NULL;
#endif
    isdeprecated = 0;
}

Dsymbol *EnumDeclaration::syntaxCopy(Dsymbol *s)
{
    Type *t = NULL;
    if (memtype)
	t = memtype->syntaxCopy();

    EnumDeclaration *ed;
    if (s)
    {	ed = (EnumDeclaration *)s;
	ed->memtype = t;
    }
    else
	ed = new EnumDeclaration(loc, ident, t);
    ScopeDsymbol::syntaxCopy(ed);
    return ed;
}

void EnumDeclaration::semantic(Scope *sc)
{   int i;
    uinteger_t number;
    Type *t;
    Scope *sce;

    //printf("EnumDeclaration::semantic(sd = %p, '%s')\n", sc->scopesym, sc->scopesym->toChars());
    if (symtab)			// if already done
	return;
    if (!memtype)
	memtype = Type::tint32;
    if (sc->stc & STCdeprecated)
	isdeprecated = 1;

    parent = sc->scopesym;
    memtype = memtype->semantic(loc, sc);

    /* Check to see if memtype is forward referenced
     */
    if (memtype->ty == Tenum)
    {	EnumDeclaration *sym = (EnumDeclaration *)memtype->toDsymbol(sc);
	if (!sym->memtype)
	{
	    error("base enum %s is forward referenced", sym->toChars());
	    memtype = Type::tint32;
	}
    }

    if (!memtype->isintegral())
    {	error("base type must be of integral type, not %s", memtype->toChars());
	memtype = Type::tint32;
    }

    t = isAnonymous() ? memtype : type;
    symtab = new DsymbolTable();
    sce = sc->push(this);
    sce->parent = this;
    number = 0;
    if (!members)		// enum ident;
	return;
    if (members->dim == 0)
	error("enum %s must have at least one member", toChars());
    int first = 1;
    for (i = 0; i < members->dim; i++)
    {
	EnumMember *em = ((Dsymbol *)members->data[i])->isEnumMember();
	Expression *e;

	if (!em)
	    /* The e->semantic(sce) can insert other symbols, such as
	     * template instances and function literals.
	     */
	    continue;

	//printf("Enum member '%s'\n",em->toChars());
	e = em->value;
	if (e)
	{
	    assert(e->dyncast() == DYNCAST_EXPRESSION);
	    e = e->semantic(sce);
	    e = e->optimize(WANTvalue);
	    // Need to copy it because we're going to change the type
	    e = e->copy();
	    e = e->implicitCastTo(sc, memtype);
	    e = e->optimize(WANTvalue);
	    number = e->toInteger();
	    e->type = t;
	}
	else
	{   // Default is the previous number plus 1

	    // Check for overflow
	    if (!first)
	    {
		switch (t->toBasetype()->ty)
		{
		    case Tbool:
			if (number == 2)	goto Loverflow;
			break;

		    case Tint8:
			if (number == 128) goto Loverflow;
			break;

		    case Tchar:
		    case Tuns8:
			if (number == 256) goto Loverflow;
			break;

		    case Tint16:
			if (number == 0x8000) goto Loverflow;
			break;

		    case Twchar:
		    case Tuns16:
			if (number == 0x10000) goto Loverflow;
			break;

		    case Tint32:
			if (number == 0x80000000) goto Loverflow;
			break;

		    case Tdchar:
		    case Tuns32:
			if (number == 0x100000000LL) goto Loverflow;
			break;

		    case Tint64:
			if (number == 0x8000000000000000LL) goto Loverflow;
			break;

		    case Tuns64:
			if (number == 0) goto Loverflow;
			break;

		    Loverflow:
			error("overflow of enum value");
			break;

		    default:
			assert(0);
		}
	    }
	    e = new IntegerExp(em->loc, number, t);
	}
	em->value = e;

	// Add to symbol table only after evaluating 'value'
	if (isAnonymous())
	{
	    //sce->enclosing->insert(em);
	    for (Scope *scx = sce->enclosing; scx; scx = scx->enclosing)
	    {
		if (scx->scopesym)
		{
		    if (!scx->scopesym->symtab)
			scx->scopesym->symtab = new DsymbolTable();
		    em->addMember(sce, scx->scopesym, 1);
		    break;
		}
	    }
	}
	else
	    em->addMember(sc, this, 1);

	if (first)
	{   first = 0;
	    defaultval = number;
	    minval = number;
	    maxval = number;
	}
	else if (memtype->isunsigned())
	{
	    if (number < minval)
		minval = number;
	    if (number > maxval)
		maxval = number;
	}
	else
	{
	    if ((sinteger_t)number < (sinteger_t)minval)
		minval = number;
	    if ((sinteger_t)number > (sinteger_t)maxval)
		maxval = number;
	}

	number++;
    }
    //printf("defaultval = %lld\n", defaultval);

    sce->pop();
    //members->print();
}

int EnumDeclaration::oneMember(Dsymbol **ps)
{
    if (isAnonymous())
	return Dsymbol::oneMembers(members, ps);
    return Dsymbol::oneMember(ps);
}

void EnumDeclaration::toCBuffer(OutBuffer *buf, HdrGenState *hgs)
{   int i;

    buf->writestring("enum ");
    if (ident)
    {	buf->writestring(ident->toChars());
	buf->writeByte(' ');
    }
    if (memtype)
    {
	buf->writestring(": ");
	memtype->toCBuffer(buf, NULL, hgs);
    }
    if (!members)
    {
	buf->writeByte(';');
	buf->writenl();
	return;
    }
    buf->writenl();
    buf->writeByte('{');
    buf->writenl();
    for (i = 0; i < members->dim; i++)
    {
	EnumMember *em = ((Dsymbol *)members->data[i])->isEnumMember();
	if (!em)
	    continue;
	//buf->writestring("    ");
	em->toCBuffer(buf, hgs);
	buf->writeByte(',');
	buf->writenl();
    }
    buf->writeByte('}');
    buf->writenl();
}

Type *EnumDeclaration::getType()
{
    return type;
}

const char *EnumDeclaration::kind()
{
    return "enum";
}

int EnumDeclaration::isDeprecated()
{
    return isdeprecated;
}

/********************************* EnumMember ****************************/

EnumMember::EnumMember(Loc loc, Identifier *id, Expression *value)
    : Dsymbol(id)
{
    this->value = value;
    this->loc = loc;
}

Dsymbol *EnumMember::syntaxCopy(Dsymbol *s)
{
    Expression *e = NULL;
    if (value)
	e = value->syntaxCopy();

    EnumMember *em;
    if (s)
    {	em = (EnumMember *)s;
	em->loc = loc;
	em->value = e;
    }
    else
	em = new EnumMember(loc, ident, e);
    return em;
}

void EnumMember::toCBuffer(OutBuffer *buf, HdrGenState *hgs)
{
    buf->writestring(ident->toChars());
    if (value)
    {
	buf->writestring(" = ");
	value->toCBuffer(buf, hgs);
    }
}

const char *EnumMember::kind()
{
    return "enum member";
}