/
dstruct.d
781 lines (723 loc) · 24.2 KB
/
dstruct.d
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// Compiler implementation of the D programming language
// Copyright (c) 1999-2015 by Digital Mars
// All Rights Reserved
// written by Walter Bright
// http://www.digitalmars.com
// Distributed under the Boost Software License, Version 1.0.
// http://www.boost.org/LICENSE_1_0.txt
module ddmd.dstruct;
import core.stdc.stdio;
import ddmd.aggregate;
import ddmd.argtypes;
import ddmd.arraytypes;
import ddmd.backend;
import ddmd.clone;
import ddmd.declaration;
import ddmd.dmodule;
import ddmd.doc;
import ddmd.dscope;
import ddmd.dsymbol;
import ddmd.dtemplate;
import ddmd.errors;
import ddmd.expression;
import ddmd.func;
import ddmd.globals;
import ddmd.hdrgen;
import ddmd.id;
import ddmd.identifier;
import ddmd.init;
import ddmd.mtype;
import ddmd.opover;
import ddmd.root.outbuffer;
import ddmd.statement;
import ddmd.tokens;
import ddmd.typinf;
import ddmd.visitor;
/***************************************
* Search toString member function for TypeInfo_Struct.
* string toString();
*/
extern (C++) FuncDeclaration search_toString(StructDeclaration sd)
{
Dsymbol s = search_function(sd, Id.tostring);
FuncDeclaration fd = s ? s.isFuncDeclaration() : null;
if (fd)
{
static __gshared TypeFunction tftostring;
if (!tftostring)
{
tftostring = new TypeFunction(null, Type.tstring, 0, LINKd);
tftostring = cast(TypeFunction)tftostring.merge();
}
fd = fd.overloadExactMatch(tftostring);
}
return fd;
}
/***************************************
* Request additonal semantic analysis for TypeInfo generation.
*/
extern (C++) void semanticTypeInfo(Scope* sc, Type t)
{
extern (C++) final class FullTypeInfoVisitor : Visitor
{
alias visit = super.visit;
public:
Scope* sc;
override void visit(Type t)
{
Type tb = t.toBasetype();
if (tb != t)
tb.accept(this);
}
override void visit(TypeNext t)
{
if (t.next)
t.next.accept(this);
}
override void visit(TypeBasic t)
{
}
override void visit(TypeVector t)
{
t.basetype.accept(this);
}
override void visit(TypeAArray t)
{
t.index.accept(this);
visit(cast(TypeNext)t);
}
override void visit(TypeFunction t)
{
visit(cast(TypeNext)t);
// Currently TypeInfo_Function doesn't store parameter types.
}
override void visit(TypeStruct t)
{
StructDeclaration sd = t.sym;
/* Step 1: create TypeInfoDeclaration
*/
if (!sc) // inline may request TypeInfo.
{
Scope scx;
scx._module = sd.getModule();
getTypeInfoType(t, &scx);
}
else
{
getTypeInfoType(t, sc);
// Bugzilla 15149, if the typeid operand type comes from a
// result of auto function, it may be yet speculative.
unSpeculative(sc, sd);
}
if (!sc || sc.minst)
sd.requestTypeInfo = true;
/* Step 2: If the TypeInfo generation requires sd.semantic3, run it later.
*/
if (!sd.members)
return; // opaque struct
if (!sd.xeq && !sd.xcmp && !sd.postblit && !sd.dtor && !sd.xhash && !search_toString(sd))
return; // none of TypeInfo-specific members
// If the struct is in a non-root module, run semantic3 to get
// correct symbols for the member function.
if (sd.semanticRun >= PASSsemantic3)
{
// semantic3 is already done
}
else if (TemplateInstance ti = sd.isInstantiated())
{
if (ti.minst && !ti.minst.isRoot())
Module.addDeferredSemantic3(sd);
}
else
{
if (sd.inNonRoot())
{
//printf("deferred sem3 for TypeInfo - sd = %s, inNonRoot = %d\n", sd->toChars(), sd->inNonRoot());
Module.addDeferredSemantic3(sd);
}
}
}
override void visit(TypeClass t)
{
}
override void visit(TypeTuple t)
{
if (t.arguments)
{
for (size_t i = 0; i < t.arguments.dim; i++)
{
Type tprm = (*t.arguments)[i].type;
if (tprm)
tprm.accept(this);
}
}
}
}
if (sc)
{
if (!sc.func)
return;
if (sc.intypeof)
return;
if (sc.flags & (SCOPEctfe | SCOPEcompile))
return;
if (!sc.minst)
return; // don't have to generate TypeInfo inside speculative scope
}
scope FullTypeInfoVisitor v = new FullTypeInfoVisitor();
v.sc = sc;
t.accept(v);
}
struct StructFlags
{
alias Type = uint;
enum Enum : int
{
hasPointers = 0x1, // NB: should use noPointers as in ClassFlags
}
alias hasPointers = Enum.hasPointers;
}
enum StructPOD : int
{
ISPODno, // struct is not POD
ISPODyes, // struct is POD
ISPODfwd, // POD not yet computed
}
alias ISPODno = StructPOD.ISPODno;
alias ISPODyes = StructPOD.ISPODyes;
alias ISPODfwd = StructPOD.ISPODfwd;
/***********************************************************
*/
extern (C++) class StructDeclaration : AggregateDeclaration
{
public:
int zeroInit; // !=0 if initialize with 0 fill
bool hasIdentityAssign; // true if has identity opAssign
bool hasIdentityEquals; // true if has identity opEquals
FuncDeclarations postblits; // Array of postblit functions
FuncDeclaration postblit; // aggregate postblit
FuncDeclaration xeq; // TypeInfo_Struct.xopEquals
FuncDeclaration xcmp; // TypeInfo_Struct.xopCmp
FuncDeclaration xhash; // TypeInfo_Struct.xtoHash
extern (C++) static __gshared FuncDeclaration xerreq; // object.xopEquals
extern (C++) static __gshared FuncDeclaration xerrcmp; // object.xopCmp
structalign_t alignment; // alignment applied outside of the struct
StructPOD ispod; // if struct is POD
// For 64 bit Efl function call/return ABI
Type arg1type;
Type arg2type;
// Even if struct is defined as non-root symbol, some built-in operations
// (e.g. TypeidExp, NewExp, ArrayLiteralExp, etc) request its TypeInfo.
// For those, today TypeInfo_Struct is generated in COMDAT.
bool requestTypeInfo;
final extern (D) this(Loc loc, Identifier id)
{
super(loc, id);
zeroInit = 0; // assume false until we do semantic processing
ispod = ISPODfwd;
// For forward references
type = new TypeStruct(this);
if (id == Id.ModuleInfo && !Module.moduleinfo)
Module.moduleinfo = this;
}
override Dsymbol syntaxCopy(Dsymbol s)
{
StructDeclaration sd = s ? cast(StructDeclaration)s : new StructDeclaration(loc, ident);
return ScopeDsymbol.syntaxCopy(sd);
}
override final void semantic(Scope* sc)
{
//printf("+StructDeclaration::semantic(this=%p, %s '%s', sizeok = %d)\n", this, parent->toChars(), toChars(), sizeok);
//static int count; if (++count == 20) assert(0);
if (semanticRun >= PASSsemanticdone)
return;
uint dprogress_save = Module.dprogress;
int errors = global.errors;
Scope* scx = null;
if (_scope)
{
sc = _scope;
scx = _scope; // save so we don't make redundant copies
_scope = null;
}
if (!parent)
{
assert(sc.parent && sc.func);
parent = sc.parent;
}
assert(parent && !isAnonymous());
type = type.semantic(loc, sc);
if (type.ty == Tstruct && (cast(TypeStruct)type).sym != this)
{
TemplateInstance ti = (cast(TypeStruct)type).sym.isInstantiated();
if (ti && isError(ti))
(cast(TypeStruct)type).sym = this;
}
// Ungag errors when not speculative
Ungag ungag = ungagSpeculative();
if (semanticRun == PASSinit)
{
protection = sc.protection;
alignment = sc.structalign;
storage_class |= sc.stc;
if (storage_class & STCdeprecated)
isdeprecated = true;
if (storage_class & STCabstract)
error("structs, unions cannot be abstract");
userAttribDecl = sc.userAttribDecl;
}
else if (symtab && !scx)
{
semanticRun = PASSsemanticdone;
return;
}
semanticRun = PASSsemantic;
if (!members) // if opaque declaration
{
semanticRun = PASSsemanticdone;
return;
}
if (!symtab)
symtab = new DsymbolTable();
if (sizeok == SIZEOKnone) // if not already done the addMember step
{
for (size_t i = 0; i < members.dim; i++)
{
Dsymbol s = (*members)[i];
//printf("adding member '%s' to '%s'\n", s->toChars(), this->toChars());
s.addMember(sc, this);
}
}
Scope* sc2 = sc.push(this);
sc2.stc &= STCsafe | STCtrusted | STCsystem;
sc2.parent = this;
if (isUnionDeclaration())
sc2.inunion = 1;
sc2.protection = Prot(PROTpublic);
sc2.explicitProtection = 0;
sc2.structalign = STRUCTALIGN_DEFAULT;
sc2.userAttribDecl = null;
if (sizeok == SIZEOKdone)
goto LafterSizeok;
sizeok = SIZEOKnone;
/* Set scope so if there are forward references, we still might be able to
* resolve individual members like enums.
*/
for (size_t i = 0; i < members.dim; i++)
{
Dsymbol s = (*members)[i];
//printf("struct: setScope %s %s\n", s->kind(), s->toChars());
s.setScope(sc2);
}
for (size_t i = 0; i < members.dim; i++)
{
Dsymbol s = (*members)[i];
s.importAll(sc2);
}
for (size_t i = 0; i < members.dim; i++)
{
Dsymbol s = (*members)[i];
s.semantic(sc2);
}
finalizeSize(sc2);
if (sizeok == SIZEOKfwd)
{
// semantic() failed because of forward references.
// Unwind what we did, and defer it for later
for (size_t i = 0; i < fields.dim; i++)
{
VarDeclaration v = fields[i];
v.offset = 0;
}
fields.setDim(0);
structsize = 0;
alignsize = 0;
sc2.pop();
_scope = scx ? scx : sc.copy();
_scope.setNoFree();
_scope._module.addDeferredSemantic(this);
Module.dprogress = dprogress_save;
//printf("\tdeferring %s\n", toChars());
return;
}
Module.dprogress++;
//printf("-StructDeclaration::semantic(this=%p, '%s')\n", this, toChars());
LafterSizeok:
// The additions of special member functions should have its own
// sub-semantic analysis pass, and have to be deferred sometimes.
// See the case in compilable/test14838.d
for (size_t i = 0; i < fields.dim; i++)
{
VarDeclaration v = fields[i];
Type tb = v.type.baseElemOf();
if (tb.ty != Tstruct)
continue;
StructDeclaration sd = (cast(TypeStruct)tb).sym;
if (sd.semanticRun >= PASSsemanticdone)
continue;
sc2.pop();
_scope = scx ? scx : sc.copy();
_scope.setNoFree();
_scope._module.addDeferredSemantic(this);
//printf("\tdeferring %s\n", toChars());
return;
}
/* Look for special member functions.
*/
aggNew = cast(NewDeclaration)search(Loc(), Id.classNew);
aggDelete = cast(DeleteDeclaration)search(Loc(), Id.classDelete);
// this->ctor is already set in finalizeSize()
dtor = buildDtor(this, sc2);
postblit = buildPostBlit(this, sc2);
buildOpAssign(this, sc2);
buildOpEquals(this, sc2);
xeq = buildXopEquals(this, sc2);
xcmp = buildXopCmp(this, sc2);
xhash = buildXtoHash(this, sc2);
/* Even if the struct is merely imported and its semantic3 is not run,
* the TypeInfo object would be speculatively stored in each object
* files. To set correct function pointer, run semantic3 for xeq and xcmp.
*/
//if ((xeq && xeq != xerreq || xcmp && xcmp != xerrcmp) && isImportedSym(this))
// Module::addDeferredSemantic3(this);
/* Defer requesting semantic3 until TypeInfo generation is actually invoked.
* See semanticTypeInfo().
*/
inv = buildInv(this, sc2);
sc2.pop();
if (ctor)
{
Dsymbol scall = search(Loc(), Id.call);
if (scall)
{
uint xerrors = global.startGagging();
sc = sc.push();
sc.tinst = null;
sc.minst = null;
FuncDeclaration fcall = resolveFuncCall(loc, sc, scall, null, null, null, 1);
sc = sc.pop();
global.endGagging(xerrors);
if (fcall && fcall.isStatic())
{
error(fcall.loc, "static opCall is hidden by constructors and can never be called");
errorSupplemental(fcall.loc, "Please use a factory method instead, or replace all constructors with static opCall.");
}
}
}
Module.dprogress++;
semanticRun = PASSsemanticdone;
TypeTuple tup = toArgTypes(type);
size_t dim = tup.arguments.dim;
if (dim >= 1)
{
assert(dim <= 2);
arg1type = (*tup.arguments)[0].type;
if (dim == 2)
arg2type = (*tup.arguments)[1].type;
}
if (sc.func)
semantic2(sc);
if (global.errors != errors)
{
// The type is no good.
type = Type.terror;
this.errors = true;
if (deferred)
deferred.errors = true;
}
if (deferred && !global.gag)
{
deferred.semantic2(sc);
deferred.semantic3(sc);
}
version (none)
{
if (type.ty == Tstruct && (cast(TypeStruct)type).sym != this)
{
printf("this = %p %s\n", this, this.toChars());
printf("type = %d sym = %p\n", type.ty, (cast(TypeStruct)type).sym);
}
}
assert(type.ty != Tstruct || (cast(TypeStruct)type).sym == this);
}
final void semanticTypeInfoMembers()
{
if (xeq && xeq._scope && xeq.semanticRun < PASSsemantic3done)
{
uint errors = global.startGagging();
xeq.semantic3(xeq._scope);
if (global.endGagging(errors))
xeq = xerreq;
}
if (xcmp && xcmp._scope && xcmp.semanticRun < PASSsemantic3done)
{
uint errors = global.startGagging();
xcmp.semantic3(xcmp._scope);
if (global.endGagging(errors))
xcmp = xerrcmp;
}
FuncDeclaration ftostr = search_toString(this);
if (ftostr && ftostr._scope && ftostr.semanticRun < PASSsemantic3done)
{
ftostr.semantic3(ftostr._scope);
}
if (xhash && xhash._scope && xhash.semanticRun < PASSsemantic3done)
{
xhash.semantic3(xhash._scope);
}
if (postblit && postblit._scope && postblit.semanticRun < PASSsemantic3done)
{
postblit.semantic3(postblit._scope);
}
if (dtor && dtor._scope && dtor.semanticRun < PASSsemantic3done)
{
dtor.semantic3(dtor._scope);
}
}
override final Dsymbol search(Loc loc, Identifier ident, int flags = IgnoreNone)
{
//printf("%s.StructDeclaration::search('%s')\n", toChars(), ident->toChars());
if (_scope && !symtab)
semantic(_scope);
if (!members || !symtab) // opaque or semantic() is not yet called
{
error("is forward referenced when looking for '%s'", ident.toChars());
return null;
}
return ScopeDsymbol.search(loc, ident, flags);
}
override const(char)* kind()
{
return "struct";
}
override final void finalizeSize(Scope* sc)
{
//printf("StructDeclaration::finalizeSize() %s\n", toChars());
if (sizeok != SIZEOKnone)
return;
// Set the offsets of the fields and determine the size of the struct
uint offset = 0;
bool isunion = isUnionDeclaration() !is null;
for (size_t i = 0; i < members.dim; i++)
{
Dsymbol s = (*members)[i];
s.setFieldOffset(this, &offset, isunion);
}
if (sizeok == SIZEOKfwd)
return;
// 0 sized struct's are set to 1 byte
if (structsize == 0)
{
structsize = 1;
alignsize = 1;
}
// Round struct size up to next alignsize boundary.
// This will ensure that arrays of structs will get their internals
// aligned properly.
if (alignment == STRUCTALIGN_DEFAULT)
structsize = (structsize + alignsize - 1) & ~(alignsize - 1);
else
structsize = (structsize + alignment - 1) & ~(alignment - 1);
sizeok = SIZEOKdone;
// Calculate fields[i].overlapped
checkOverlappedFields();
// Determine if struct is all zeros or not
zeroInit = 1;
for (size_t i = 0; i < fields.dim; i++)
{
VarDeclaration vd = fields[i];
if (!vd.isDataseg())
{
if (vd._init)
{
// Should examine init to see if it is really all 0's
zeroInit = 0;
break;
}
else
{
if (!vd.type.isZeroInit(loc))
{
zeroInit = 0;
break;
}
}
}
}
// Look for the constructor, for the struct literal/constructor call expression
ctor = searchCtor();
if (ctor)
{
// Finish all constructors semantics to determine this->noDefaultCtor.
struct SearchCtor
{
extern (C++) static int fp(Dsymbol s, void* ctxt)
{
CtorDeclaration f = s.isCtorDeclaration();
if (f && f.semanticRun == PASSinit)
f.semantic(null);
return 0;
}
}
for (size_t i = 0; i < members.dim; i++)
{
Dsymbol s = (*members)[i];
s.apply(&SearchCtor.fp, null);
}
}
}
/***************************************
* Fit elements[] to the corresponding type of field[].
* Input:
* loc
* sc
* elements The explicit arguments that given to construct object.
* stype The constructed object type.
* Returns false if any errors occur.
* Otherwise, returns true and elements[] are rewritten for the output.
*/
final bool fit(Loc loc, Scope* sc, Expressions* elements, Type stype)
{
if (!elements)
return true;
size_t nfields = fields.dim - isNested();
size_t offset = 0;
for (size_t i = 0; i < elements.dim; i++)
{
Expression e = (*elements)[i];
if (!e)
continue;
e = resolveProperties(sc, e);
if (i >= nfields)
{
if (i == fields.dim - 1 && isNested() && e.op == TOKnull)
{
// CTFE sometimes creates null as hidden pointer; we'll allow this.
continue;
}
.error(loc, "more initializers than fields (%d) of %s", nfields, toChars());
return false;
}
VarDeclaration v = fields[i];
if (v.offset < offset)
{
.error(loc, "overlapping initialization for %s", v.toChars());
return false;
}
offset = cast(uint)(v.offset + v.type.size());
Type t = v.type;
if (stype)
t = t.addMod(stype.mod);
Type origType = t;
Type tb = t.toBasetype();
/* Look for case of initializing a static array with a too-short
* string literal, such as:
* char[5] foo = "abc";
* Allow this by doing an explicit cast, which will lengthen the string
* literal.
*/
if (e.op == TOKstring && tb.ty == Tsarray)
{
StringExp se = cast(StringExp)e;
Type typeb = se.type.toBasetype();
TY tynto = tb.nextOf().ty;
if (!se.committed && (typeb.ty == Tarray || typeb.ty == Tsarray) && (tynto == Tchar || tynto == Twchar || tynto == Tdchar) && se.length(cast(int)tb.nextOf().size()) < (cast(TypeSArray)tb).dim.toInteger())
{
e = se.castTo(sc, t);
goto L1;
}
}
while (!e.implicitConvTo(t) && tb.ty == Tsarray)
{
/* Static array initialization, as in:
* T[3][5] = e;
*/
t = tb.nextOf();
tb = t.toBasetype();
}
if (!e.implicitConvTo(t))
t = origType; // restore type for better diagnostic
e = e.implicitCastTo(sc, t);
L1:
if (e.op == TOKerror)
return false;
(*elements)[i] = e.isLvalue() ? callCpCtor(sc, e) : valueNoDtor(e);
}
return true;
}
/***************************************
* Return true if struct is POD (Plain Old Data).
* This is defined as:
* not nested
* no postblits, destructors, or assignment operators
* no 'ref' fields or fields that are themselves non-POD
* The idea being these are compatible with C structs.
*/
final bool isPOD()
{
// If we've already determined whether this struct is POD.
if (ispod != ISPODfwd)
return (ispod == ISPODyes);
ispod = ISPODyes;
if (enclosing || postblit || dtor)
ispod = ISPODno;
// Recursively check all fields are POD.
for (size_t i = 0; i < fields.dim; i++)
{
VarDeclaration v = fields[i];
if (v.storage_class & STCref)
{
ispod = ISPODno;
break;
}
Type tv = v.type.baseElemOf();
if (tv.ty == Tstruct)
{
TypeStruct ts = cast(TypeStruct)tv;
StructDeclaration sd = ts.sym;
if (!sd.isPOD())
{
ispod = ISPODno;
break;
}
}
}
return (ispod == ISPODyes);
}
override final StructDeclaration isStructDeclaration()
{
return this;
}
override void accept(Visitor v)
{
v.visit(this);
}
}
/***********************************************************
*/
extern (C++) final class UnionDeclaration : StructDeclaration
{
public:
extern (D) this(Loc loc, Identifier id)
{
super(loc, id);
}
override Dsymbol syntaxCopy(Dsymbol s)
{
assert(!s);
auto ud = new UnionDeclaration(loc, ident);
return StructDeclaration.syntaxCopy(ud);
}
override const(char)* kind()
{
return "union";
}
override UnionDeclaration isUnionDeclaration()
{
return this;
}
override void accept(Visitor v)
{
v.visit(this);
}
}