view dmd2/traits.c @ 1117:4c20fcc4252b

Fun with parameter attributes: For several of the "synthetic" parameters added to D functions, we can apply noalias and nocapture. They are sret parameters, 'nest' pointers passed to nested functions, and _argptr: Nocapture: - Sret and nest are nocapture because they don't represent D-level variables, and thus the callee can't (validly) obtain a pointer to them, let alone keep it around after it returns. - _argptr is nocapture because although the callee has access to it as a pointer, that pointer is invalidated when it returns. All three are noalias because they're function-local variables - Sret and _argptr are noalias because they're freshly alloca'd memory only used for a single function call that's not allowed to keep an aliasing pointer to it around (since the parameter is nocapture). - 'Nest' is noalias because the callee only ever has access to one such pointer per parent function, and every parent function has a different one. This commit also ensures attributes set on sret, _arguments and _argptr are propagated to calls to such functions. It also adds one exception to the general rule that attributes on function types should propagate to calls: the type of a delegate's function pointer has a 'nest' parameter, but this can either be a true 'nest' (for delegates to nested functions) or a 'this' (for delegates to member functions). Since 'this' is neither noalias nor nocapture, and there's generally no way to tell which one it is, we remove these attributes at the call site if the callee is a delegate.
author Frits van Bommel <fvbommel wxs.nl>
date Sat, 14 Mar 2009 22:15:31 +0100
parents f04dde6e882c
children 638d16625da2
line wrap: on
line source


// Compiler implementation of the D programming language
// Copyright (c) 1999-2007 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 <stdlib.h>
#include <ctype.h>
#include <assert.h>
#include <complex.h>
#include <math.h>

#if IN_GCC
// Issues with using -include total.h (defines integer_t) and then complex.h fails...
#undef integer_t
#endif

#ifdef __APPLE__
#define integer_t dmd_integer_t
#endif

#if IN_GCC || IN_LLVM
#include "mem.h"
#elif _WIN32
#include "..\root\mem.h"
#elif linux
#include "../root/mem.h"
#endif

//#include "port.h"
#include "mtype.h"
#include "init.h"
#include "expression.h"
#include "template.h"
#include "utf.h"
#include "enum.h"
#include "scope.h"
#include "statement.h"
#include "declaration.h"
#include "aggregate.h"
#include "import.h"
#include "id.h"
#include "dsymbol.h"
#include "module.h"
#include "attrib.h"
#include "hdrgen.h"
#include "parse.h"

#define LOGSEMANTIC	0

/************************************************
 * Delegate to be passed to overloadApply() that looks
 * for virtual functions.
 */

struct Pvirtuals
{
    Expression *e1;
    Expressions *exps;
};

static int fpvirtuals(void *param, FuncDeclaration *f)
{   Pvirtuals *p = (Pvirtuals *)param;

    if (f->isVirtual())
    {	Expression *e;

	if (p->e1->op == TOKdotvar)
	{   DotVarExp *dve = (DotVarExp *)p->e1;
	    e = new DotVarExp(0, dve->e1, f);
	}
	else
	    e = new DsymbolExp(0, f);
	p->exps->push(e);
    }
    return 0;
}

/************************ TraitsExp ************************************/

Expression *TraitsExp::semantic(Scope *sc)
{
#if LOGSEMANTIC
    printf("TraitsExp::semantic() %s\n", toChars());
#endif
    if (ident != Id::compiles && ident != Id::isSame)
	TemplateInstance::semanticTiargs(loc, sc, args, 1);
    size_t dim = args ? args->dim : 0;
    Object *o;
    FuncDeclaration *f;

#define ISTYPE(cond) \
	for (size_t i = 0; i < dim; i++)	\
	{   Type *t = getType((Object *)args->data[i]);	\
	    if (!t)				\
		goto Lfalse;			\
	    if (!(cond))			\
		goto Lfalse;			\
	}					\
	if (!dim)				\
	    goto Lfalse;			\
	goto Ltrue;

#define ISDSYMBOL(cond) \
	for (size_t i = 0; i < dim; i++)	\
	{   Dsymbol *s = getDsymbol((Object *)args->data[i]);	\
	    if (!s)				\
		goto Lfalse;			\
	    if (!(cond))			\
		goto Lfalse;			\
	}					\
	if (!dim)				\
	    goto Lfalse;			\
	goto Ltrue;



    if (ident == Id::isArithmetic)
    {
	ISTYPE(t->isintegral() || t->isfloating())
    }
    else if (ident == Id::isFloating)
    {
	ISTYPE(t->isfloating())
    }
    else if (ident == Id::isIntegral)
    {
	ISTYPE(t->isintegral())
    }
    else if (ident == Id::isScalar)
    {
	ISTYPE(t->isscalar())
    }
    else if (ident == Id::isUnsigned)
    {
	ISTYPE(t->isunsigned())
    }
    else if (ident == Id::isAssociativeArray)
    {
	ISTYPE(t->toBasetype()->ty == Taarray)
    }
    else if (ident == Id::isStaticArray)
    {
	ISTYPE(t->toBasetype()->ty == Tsarray)
    }
    else if (ident == Id::isAbstractClass)
    {
	ISTYPE(t->toBasetype()->ty == Tclass && ((TypeClass *)t->toBasetype())->sym->isAbstract())
    }
    else if (ident == Id::isFinalClass)
    {
	ISTYPE(t->toBasetype()->ty == Tclass && ((TypeClass *)t->toBasetype())->sym->storage_class & STCfinal)
    }
    else if (ident == Id::isAbstractFunction)
    {
	ISDSYMBOL((f = s->isFuncDeclaration()) != NULL && f->isAbstract())
    }
    else if (ident == Id::isVirtualFunction)
    {
	ISDSYMBOL((f = s->isFuncDeclaration()) != NULL && f->isVirtual())
    }
    else if (ident == Id::isFinalFunction)
    {
	ISDSYMBOL((f = s->isFuncDeclaration()) != NULL && f->isFinal())
    }
    else if (ident == Id::hasMember ||
	     ident == Id::getMember ||
	     ident == Id::getVirtualFunctions)
    {
	if (dim != 2)
	    goto Ldimerror;
	Object *o = (Object *)args->data[0];
	Expression *e = isExpression((Object *)args->data[1]);
	if (!e)
	{   error("expression expected as second argument of __traits %s", ident->toChars());
	    goto Lfalse;
	}
	e = e->optimize(WANTvalue | WANTinterpret);
	if (e->op != TOKstring)
	{   error("string expected as second argument of __traits %s instead of %s", ident->toChars(), e->toChars());
	    goto Lfalse;
	}
	StringExp *se = (StringExp *)e;
	se = se->toUTF8(sc);
	if (se->sz != 1)
	{   error("string must be chars");
	    goto Lfalse;
	}
	Identifier *id = Lexer::idPool((char *)se->string);

	Type *t = isType(o);
	e = isExpression(o);
	Dsymbol *s = isDsymbol(o);
	if (t)
	    e = new TypeDotIdExp(loc, t, id);
	else if (e)
	    e = new DotIdExp(loc, e, id);
	else if (s)
	{   e = new DsymbolExp(loc, s);
	    e = new DotIdExp(loc, e, id);
	}
	else
	{   error("invalid first argument");
	    goto Lfalse;
	}

	if (ident == Id::hasMember)
	{   /* Take any errors as meaning it wasn't found
	     */
	    unsigned errors = global.errors;
	    global.gag++;
	    e = e->semantic(sc);
	    global.gag--;
	    if (errors != global.errors)
	    {	if (global.gag == 0)
		    global.errors = errors;
		goto Lfalse;
	    }
	    else
		goto Ltrue;
	}
	else if (ident == Id::getMember)
	{
	    e = e->semantic(sc);
	    return e;
	}
	else if (ident == Id::getVirtualFunctions)
	{
	    unsigned errors = global.errors;
	    Expression *ex = e;
	    e = e->semantic(sc);
	    if (errors < global.errors)
		error("%s cannot be resolved", ex->toChars());

	    /* Create tuple of virtual function overloads of e
	     */
	    //e->dump(0);
	    Expressions *exps = new Expressions();
	    FuncDeclaration *f;
	    if (e->op == TOKvar)
	    {	VarExp *ve = (VarExp *)e;
		f = ve->var->isFuncDeclaration();
	    }
	    else if (e->op == TOKdotvar)
	    {	DotVarExp *dve = (DotVarExp *)e;
		f = dve->var->isFuncDeclaration();
	    }
	    else
		f = NULL;
	    Pvirtuals p;
	    p.exps = exps;
	    p.e1 = e;
	    overloadApply(f, fpvirtuals, &p);

	    TupleExp *tup = new TupleExp(loc, exps);
	    return tup->semantic(sc);
	}
	else
	    assert(0);
    }
    else if (ident == Id::classInstanceSize)
    {
	if (dim != 1)
	    goto Ldimerror;
	Object *o = (Object *)args->data[0];
	Dsymbol *s = getDsymbol(o);
	ClassDeclaration *cd;
	if (!s || (cd = s->isClassDeclaration()) == NULL)
	{
	    error("first argument is not a class");
	    goto Lfalse;
	}
	return new IntegerExp(loc, cd->structsize, Type::tsize_t);
    }
    else if (ident == Id::allMembers || ident == Id::derivedMembers)
    {
	if (dim != 1)
	    goto Ldimerror;
	Object *o = (Object *)args->data[0];
	Dsymbol *s = getDsymbol(o);
	ScopeDsymbol *sd;
	if (!s)
	{
	    error("argument has no members");
	    goto Lfalse;
	}
	if ((sd = s->isScopeDsymbol()) == NULL)
	{
	    error("%s %s has no members", s->kind(), s->toChars());
	    goto Lfalse;
	}
	Expressions *exps = new Expressions;
	while (1)
	{   size_t dim = ScopeDsymbol::dim(sd->members);
	    for (size_t i = 0; i < dim; i++)
	    {
		Dsymbol *sm = ScopeDsymbol::getNth(sd->members, i);
		//printf("\t[%i] %s %s\n", i, sm->kind(), sm->toChars());
		if (sm->ident)
		{
		    //printf("\t%s\n", sm->ident->toChars());
		    char *str = sm->ident->toChars();

		    /* Skip if already present in exps[]
		     */
		    for (size_t j = 0; j < exps->dim; j++)
		    {   StringExp *se2 = (StringExp *)exps->data[j];
			if (strcmp(str, (char *)se2->string) == 0)
			    goto Lnext;
		    }

		    StringExp *se = new StringExp(loc, str);
		    exps->push(se);
		}
	    Lnext:
		;
	    }
	    ClassDeclaration *cd = sd->isClassDeclaration();
	    if (cd && cd->baseClass && ident == Id::allMembers)
		sd = cd->baseClass;	// do again with base class
	    else
		break;
	}
	Expression *e = new ArrayLiteralExp(loc, exps);
	e = e->semantic(sc);
	return e;
    }
    else if (ident == Id::compiles)
    {
	/* Determine if all the objects - types, expressions, or symbols -
	 * compile without error
	 */
	if (!dim)
	    goto Lfalse;

	for (size_t i = 0; i < dim; i++)
	{   Object *o = (Object *)args->data[i];
	    Type *t;
	    Expression *e;
	    Dsymbol *s;

	    unsigned errors = global.errors;
	    global.gag++;

	    t = isType(o);
	    if (t)
	    {	t->resolve(loc, sc, &e, &t, &s);
		if (t)
		    t->semantic(loc, sc);
		else if (e)
		    e->semantic(sc);
	    }
	    else
	    {	e = isExpression(o);
		if (e)
		    e->semantic(sc);
	    }

	    global.gag--;
	    if (errors != global.errors)
	    {   if (global.gag == 0)
		    global.errors = errors;
		goto Lfalse;
	    }
	}
	goto Ltrue;
    }
    else if (ident == Id::isSame)
    {	/* Determine if two symbols are the same
	 */
	if (dim != 2)
	    goto Ldimerror;
	TemplateInstance::semanticTiargs(loc, sc, args, 0);
	Object *o1 = (Object *)args->data[0];
	Object *o2 = (Object *)args->data[1];
	Dsymbol *s1 = getDsymbol(o1);
	Dsymbol *s2 = getDsymbol(o2);

#if 0
	printf("o1: %p\n", o1);
	printf("o2: %p\n", o2);
	if (!s1)
	{   Expression *ea = isExpression(o1);
	    if (ea)
		printf("%s\n", ea->toChars());
	    Type *ta = isType(o1);
	    if (ta)
		printf("%s\n", ta->toChars());
	    goto Lfalse;
	}
	else
	    printf("%s %s\n", s1->kind(), s1->toChars());
#endif
	if (!s1 && !s2)
	{   Expression *ea1 = isExpression(o1);
	    Expression *ea2 = isExpression(o2);
	    if (ea1 && ea2 && ea1->equals(ea2))
		goto Ltrue;
	}

	if (!s1 || !s2)
	    goto Lfalse;

	s1 = s1->toAlias();
	s2 = s2->toAlias();

	if (s1 == s2)
	    goto Ltrue;
	else
	    goto Lfalse;
    }
    else
    {	error("unrecognized trait %s", ident->toChars());
	goto Lfalse;
    }

    return NULL;

Lnottype:
    error("%s is not a type", o->toChars());
    goto Lfalse;

Ldimerror:
    error("wrong number of arguments %d", dim);
    goto Lfalse;


Lfalse:
    return new IntegerExp(loc, 0, Type::tbool);

Ltrue:
    return new IntegerExp(loc, 1, Type::tbool);
}