Mercurial > projects > ldc
view dmd2/enum.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
// Copyright (c) 1999-2008 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 "id.h" #include "expression.h" #include "module.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 = NULL; minval = NULL; defaultval = NULL; sinit = NULL; scope = NULL; 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) { Type *t; Scope *sce; //printf("EnumDeclaration::semantic(sd = %p, '%s') %s\n", sc->scopesym, sc->scopesym->toChars(), toChars()); //printf("EnumDeclaration::semantic() %s\n", toChars()); if (!members) // enum ident; return; if (!memtype && !isAnonymous()) { // Set memtype if we can to reduce fwd reference errors memtype = Type::tint32; // case 1) enum ident { ... } } if (symtab) // if already done { if (!scope) return; // semantic() already completed } else symtab = new DsymbolTable(); Scope *scx = NULL; if (scope) { sc = scope; scx = scope; // save so we don't make redundant copies scope = NULL; } if (sc->stc & STCdeprecated) isdeprecated = 1; parent = sc->parent; /* The separate, and distinct, cases are: * 1. enum { ... } * 2. enum : memtype { ... } * 3. enum ident { ... } * 4. enum ident : memtype { ... } */ if (memtype) { 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 || !sym->members || !sym->symtab || sym->scope) { // memtype is forward referenced, so try again later scope = scx ? scx : new Scope(*sc); scope->setNoFree(); scope->module->addDeferredSemantic(this); printf("\tdeferring %s\n", toChars()); return; } } #if 0 // Decided to abandon this restriction for D 2.0 if (!memtype->isintegral()) { error("base type must be of integral type, not %s", memtype->toChars()); memtype = Type::tint32; } #endif } type = type->semantic(loc, sc); if (isAnonymous()) sce = sc; else { sce = sc->push(this); sce->parent = this; } if (members->dim == 0) error("enum %s must have at least one member", toChars()); int first = 1; Expression *elast = NULL; for (int 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()); if (em->type) em->type = em->type->semantic(em->loc, sce); e = em->value; if (e) { assert(e->dyncast() == DYNCAST_EXPRESSION); e = e->semantic(sce); e = e->optimize(WANTvalue | WANTinterpret); if (memtype) { e = e->implicitCastTo(sce, memtype); e = e->optimize(WANTvalue | WANTinterpret); if (!isAnonymous()) e = e->castTo(sce, type); t = memtype; } else if (em->type) { e = e->implicitCastTo(sce, em->type); e = e->optimize(WANTvalue | WANTinterpret); assert(isAnonymous()); t = e->type; } else t = e->type; } else if (first) { if (memtype) t = memtype; else if (em->type) t = em->type; else t = Type::tint32; e = new IntegerExp(em->loc, 0, Type::tint32); e = e->implicitCastTo(sce, t); e = e->optimize(WANTvalue | WANTinterpret); if (!isAnonymous()) e = e->castTo(sce, type); } else { // Set value to (elast + 1). // But first check that (elast != t.max) assert(elast); e = new EqualExp(TOKequal, em->loc, elast, t->getProperty(0, Id::max)); e = e->semantic(sce); e = e->optimize(WANTvalue | WANTinterpret); if (e->toInteger()) error("overflow of enum value %s", elast->toChars()); // Now set e to (elast + 1) e = new AddExp(em->loc, elast, new IntegerExp(em->loc, 1, Type::tint32)); e = e->semantic(sce); e = e->castTo(sce, elast->type); e = e->optimize(WANTvalue | WANTinterpret); } elast = e; em->value = e; // Add to symbol table only after evaluating 'value' if (isAnonymous()) { /* Anonymous enum members get added to enclosing scope. */ for (Scope *scx = sce; 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); /* Compute .min, .max and .default values. * If enum doesn't have a name, we can never identify the enum type, * so there is no purpose for a .min, .max or .default */ if (!isAnonymous()) { if (first) { defaultval = e; minval = e; maxval = e; } else { Expression *ec; /* In order to work successfully with UDTs, * build expressions to do the comparisons, * and let the semantic analyzer and constant * folder give us the result. */ // Compute if(e < minval) ec = new CmpExp(TOKlt, em->loc, e, minval); ec = ec->semantic(sce); ec = ec->optimize(WANTvalue | WANTinterpret); if (ec->toInteger()) minval = e; ec = new CmpExp(TOKgt, em->loc, e, maxval); ec = ec->semantic(sce); ec = ec->optimize(WANTvalue | WANTinterpret); if (ec->toInteger()) maxval = e; } } first = 0; } //printf("defaultval = %lld\n", defaultval); //if (defaultval) printf("defaultval: %s %s\n", defaultval->toChars(), defaultval->type->toChars()); if (sc != sce) 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; } Dsymbol *EnumDeclaration::search(Loc loc, Identifier *ident, int flags) { //printf("%s.EnumDeclaration::search('%s')\n", toChars(), ident->toChars()); if (scope) // Try one last time to resolve this enum semantic(scope); if (!members || !symtab || scope) { error("is forward referenced when looking for '%s'", ident->toChars()); //*(char*)0=0; return NULL; } Dsymbol *s = ScopeDsymbol::search(loc, ident, flags); return s; } /********************************* EnumMember ****************************/ EnumMember::EnumMember(Loc loc, Identifier *id, Expression *value, Type *type) : Dsymbol(id) { this->value = value; this->type = type; this->loc = loc; } Dsymbol *EnumMember::syntaxCopy(Dsymbol *s) { Expression *e = NULL; if (value) e = value->syntaxCopy(); Type *t = NULL; if (type) t = type->syntaxCopy(); EnumMember *em; if (s) { em = (EnumMember *)s; em->loc = loc; em->value = e; em->type = t; } else em = new EnumMember(loc, ident, e, t); return em; } void EnumMember::toCBuffer(OutBuffer *buf, HdrGenState *hgs) { if (type) type->toCBuffer(buf, ident, hgs); else buf->writestring(ident->toChars()); if (value) { buf->writestring(" = "); value->toCBuffer(buf, hgs); } } const char *EnumMember::kind() { return "enum member"; }