/
clone.d
1182 lines (1100 loc) · 39.1 KB
/
clone.d
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/**
* Compiler implementation of the
* $(LINK2 http://www.dlang.org, D programming language).
*
* Copyright: Copyright (C) 1999-2019 by The D Language Foundation, All Rights Reserved
* Authors: $(LINK2 http://www.digitalmars.com, Walter Bright)
* License: $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
* Source: $(LINK2 https://github.com/dlang/dmd/blob/master/src/dmd/clone.d, _clone.d)
* Documentation: https://dlang.org/phobos/dmd_clone.html
* Coverage: https://codecov.io/gh/dlang/dmd/src/master/src/dmd/clone.d
*/
module dmd.clone;
import core.stdc.stdio;
import dmd.aggregate;
import dmd.arraytypes;
import dmd.dclass;
import dmd.declaration;
import dmd.dscope;
import dmd.dstruct;
import dmd.dsymbol;
import dmd.dsymbolsem;
import dmd.dtemplate;
import dmd.expression;
import dmd.expressionsem;
import dmd.func;
import dmd.globals;
import dmd.id;
import dmd.identifier;
import dmd.init;
import dmd.mtype;
import dmd.opover;
import dmd.semantic2;
import dmd.statement;
import dmd.target;
import dmd.typesem;
import dmd.tokens;
/*******************************************
* Merge function attributes pure, nothrow, @safe, @nogc, and @disable
* from f into s1.
* Params:
* s1 = storage class to merge into
* f = function
* Returns:
* merged storage class
*/
StorageClass mergeFuncAttrs(StorageClass s1, const FuncDeclaration f) pure
{
if (!f)
return s1;
StorageClass s2 = (f.storage_class & STC.disable);
TypeFunction tf = cast(TypeFunction)f.type;
if (tf.trust == TRUST.safe)
s2 |= STC.safe;
else if (tf.trust == TRUST.system)
s2 |= STC.system;
else if (tf.trust == TRUST.trusted)
s2 |= STC.trusted;
if (tf.purity != PURE.impure)
s2 |= STC.pure_;
if (tf.isnothrow)
s2 |= STC.nothrow_;
if (tf.isnogc)
s2 |= STC.nogc;
const sa = s1 & s2;
const so = s1 | s2;
StorageClass stc = (sa & (STC.pure_ | STC.nothrow_ | STC.nogc)) | (so & STC.disable);
if (so & STC.system)
stc |= STC.system;
else if (sa & STC.trusted)
stc |= STC.trusted;
else if ((so & (STC.trusted | STC.safe)) == (STC.trusted | STC.safe))
stc |= STC.trusted;
else if (sa & STC.safe)
stc |= STC.safe;
return stc;
}
/*******************************************
* Check given aggregate actually has an identity opAssign or not.
* Params:
* ad = struct or class
* sc = current scope
* Returns:
* if found, returns FuncDeclaration of opAssign, otherwise null
*/
FuncDeclaration hasIdentityOpAssign(AggregateDeclaration ad, Scope* sc)
{
Dsymbol assign = search_function(ad, Id.assign);
if (assign)
{
/* check identity opAssign exists
*/
scope er = new NullExp(ad.loc, ad.type); // dummy rvalue
scope el = new IdentifierExp(ad.loc, Id.p); // dummy lvalue
el.type = ad.type;
Expressions a;
a.setDim(1);
const errors = global.startGagging(); // Do not report errors, even if the template opAssign fbody makes it.
sc = sc.push();
sc.tinst = null;
sc.minst = null;
a[0] = er;
auto f = resolveFuncCall(ad.loc, sc, assign, null, ad.type, &a, FuncResolveFlag.quiet);
if (!f)
{
a[0] = el;
f = resolveFuncCall(ad.loc, sc, assign, null, ad.type, &a, FuncResolveFlag.quiet);
}
sc = sc.pop();
global.endGagging(errors);
if (f)
{
if (f.errors)
return null;
auto fparams = f.getParameterList();
if (fparams.length)
{
auto fparam0 = fparams[0];
if (fparam0.type.toDsymbol(null) != ad)
f = null;
}
}
// BUGS: This detection mechanism cannot find some opAssign-s like follows:
// struct S { void opAssign(ref immutable S) const; }
return f;
}
return null;
}
/*******************************************
* We need an opAssign for the struct if
* it has a destructor or a postblit.
* We need to generate one if a user-specified one does not exist.
*/
private bool needOpAssign(StructDeclaration sd)
{
//printf("StructDeclaration::needOpAssign() %s\n", sd.toChars());
static bool isNeeded()
{
//printf("\tneed\n");
return true;
}
if (sd.isUnionDeclaration())
return !isNeeded();
if (sd.hasIdentityAssign || // because has identity==elaborate opAssign
sd.dtor ||
sd.postblit)
return isNeeded();
/* If any of the fields need an opAssign, then we
* need it too.
*/
foreach (v; sd.fields)
{
if (v.storage_class & STC.ref_)
continue;
if (v.overlapped) // if field of a union
continue; // user must handle it themselves
Type tv = v.type.baseElemOf();
if (tv.ty == Tstruct)
{
TypeStruct ts = cast(TypeStruct)tv;
if (ts.sym.isUnionDeclaration())
continue;
if (needOpAssign(ts.sym))
return isNeeded();
}
}
return !isNeeded();
}
/******************************************
* Build opAssign for a `struct`.
*
* The generated `opAssign` function has the following signature:
*---
*ref S opAssign(S s) // S is the name of the `struct`
*---
*
* The opAssign function will be built for a struct `S` if the
* following constraints are met:
*
* 1. `S` does not have an identity `opAssign` defined.
*
* 2. `S` has at least one of the following members: a postblit (user-defined or
* generated for fields that have a defined postblit), a destructor
* (user-defined or generated for fields that have a defined destructor)
* or at least one field that has a defined `opAssign`.
*
* 3. `S` does not have any non-mutable fields.
*
* If `S` has a disabled destructor or at least one field that has a disabled
* `opAssign`, `S.opAssign` is going to be generated, but marked with `@disable`
*
* If `S` defines a destructor, the generated code for `opAssign` is:
*
*---
*S __swap = void;
*__swap = this; // bit copy
*this = s; // bit copy
*__swap.dtor();
*---
*
* Otherwise, if `S` defines a postblit, the generated code for `opAssign` is:
*
*---
*this = s;
*---
*
* Note that the parameter to the generated `opAssign` is passed by value, which means
* that the postblit is going to be called (if it is defined) in both of the above
* situations before entering the body of `opAssign`. The assignments in the above generated
* function bodies are blit expressions, so they can be regarded as `memcpy`s
* (`opAssign` is not called as this will result in an infinite recursion; the postblit
* is not called because it has already been called when the parameter was passed by value).
*
* If `S` does not have a postblit or a destructor, but contains at least one field that defines
* an `opAssign` function (which is not disabled), then the body will make member-wise
* assignments:
*
*---
*this.field1 = s.field1;
*this.field2 = s.field2;
*...;
*---
*
* In this situation, the assignemnts are actual assign expressions (`opAssign` is used
* if defined).
*
* References:
* https://dlang.org/spec/struct.html#assign-overload
* Params:
* sd = struct to generate opAssign for
* sc = context
* Returns:
* generated `opAssign` function
*/
FuncDeclaration buildOpAssign(StructDeclaration sd, Scope* sc)
{
if (FuncDeclaration f = hasIdentityOpAssign(sd, sc))
{
sd.hasIdentityAssign = true;
return f;
}
// Even if non-identity opAssign is defined, built-in identity opAssign
// will be defined.
if (!needOpAssign(sd))
return null;
//printf("StructDeclaration::buildOpAssign() %s\n", sd.toChars());
StorageClass stc = STC.safe | STC.nothrow_ | STC.pure_ | STC.nogc;
Loc declLoc = sd.loc;
Loc loc; // internal code should have no loc to prevent coverage
// One of our sub-field might have `@disable opAssign` so we need to
// check for it.
// In this event, it will be reflected by having `stc` (opAssign's
// storage class) include `STC.disabled`.
foreach (v; sd.fields)
{
if (v.storage_class & STC.ref_)
continue;
if (v.overlapped)
continue;
Type tv = v.type.baseElemOf();
if (tv.ty != Tstruct)
continue;
StructDeclaration sdv = (cast(TypeStruct)tv).sym;
stc = mergeFuncAttrs(stc, hasIdentityOpAssign(sdv, sc));
}
if (sd.dtor || sd.postblit)
{
// if the type is not assignable, we cannot generate opAssign
if (!sd.type.isAssignable()) // https://issues.dlang.org/show_bug.cgi?id=13044
return null;
stc = mergeFuncAttrs(stc, sd.dtor);
if (stc & STC.safe)
stc = (stc & ~STC.safe) | STC.trusted;
}
auto fparams = new Parameters();
fparams.push(new Parameter(STC.nodtor, sd.type, Id.p, null, null));
auto tf = new TypeFunction(ParameterList(fparams), sd.handleType(), LINK.d, stc | STC.ref_);
auto fop = new FuncDeclaration(declLoc, Loc.initial, Id.assign, stc, tf);
fop.storage_class |= STC.inference;
fop.generated = true;
Expression e;
if (stc & STC.disable)
{
e = null;
}
/* Do swap this and rhs.
* __swap = this; this = s; __swap.dtor();
*/
else if (sd.dtor)
{
//printf("\tswap copy\n");
TypeFunction tdtor = cast(TypeFunction)sd.dtor.type;
assert(tdtor.ty == Tfunction);
auto idswap = Identifier.generateId("__swap");
auto swap = new VarDeclaration(loc, sd.type, idswap, new VoidInitializer(loc));
swap.storage_class |= STC.nodtor | STC.temp | STC.ctfe;
if (tdtor.isscope)
swap.storage_class |= STC.scope_;
auto e1 = new DeclarationExp(loc, swap);
auto e2 = new BlitExp(loc, new VarExp(loc, swap), new ThisExp(loc));
auto e3 = new BlitExp(loc, new ThisExp(loc), new IdentifierExp(loc, Id.p));
/* Instead of running the destructor on s, run it
* on swap. This avoids needing to copy swap back in to s.
*/
auto e4 = new CallExp(loc, new DotVarExp(loc, new VarExp(loc, swap), sd.dtor, false));
e = Expression.combine(e1, e2, e3, e4);
}
/* postblit was called when the value was passed to opAssign, we just need to blit the result */
else if (sd.postblit)
e = new BlitExp(loc, new ThisExp(loc), new IdentifierExp(loc, Id.p));
else
{
/* Do memberwise copy.
*
* If sd is a nested struct, its vthis field assignment is:
* 1. If it's nested in a class, it's a rebind of class reference.
* 2. If it's nested in a function or struct, it's an update of void*.
* In both cases, it will change the parent context.
*/
//printf("\tmemberwise copy\n");
e = null;
foreach (v; sd.fields)
{
// this.v = s.v;
auto ec = new AssignExp(loc,
new DotVarExp(loc, new ThisExp(loc), v),
new DotVarExp(loc, new IdentifierExp(loc, Id.p), v));
e = Expression.combine(e, ec);
}
}
if (e)
{
Statement s1 = new ExpStatement(loc, e);
/* Add:
* return this;
*/
auto er = new ThisExp(loc);
Statement s2 = new ReturnStatement(loc, er);
fop.fbody = new CompoundStatement(loc, s1, s2);
tf.isreturn = true;
}
sd.members.push(fop);
fop.addMember(sc, sd);
sd.hasIdentityAssign = true; // temporary mark identity assignable
const errors = global.startGagging(); // Do not report errors, even if the template opAssign fbody makes it.
Scope* sc2 = sc.push();
sc2.stc = 0;
sc2.linkage = LINK.d;
fop.dsymbolSemantic(sc2);
fop.semantic2(sc2);
// https://issues.dlang.org/show_bug.cgi?id=15044
//semantic3(fop, sc2); // isn't run here for lazy forward reference resolution.
sc2.pop();
if (global.endGagging(errors)) // if errors happened
{
// Disable generated opAssign, because some members forbid identity assignment.
fop.storage_class |= STC.disable;
fop.fbody = null; // remove fbody which contains the error
}
//printf("-StructDeclaration::buildOpAssign() %s, errors = %d\n", sd.toChars(), (fop.storage_class & STC.disable) != 0);
//printf("fop.type: %s\n", fop.type.toPrettyChars());
return fop;
}
/*******************************************
* We need an opEquals for the struct if
* any fields has an opEquals.
* Generate one if a user-specified one does not exist.
*/
bool needOpEquals(StructDeclaration sd)
{
//printf("StructDeclaration::needOpEquals() %s\n", sd.toChars());
if (sd.isUnionDeclaration())
goto Ldontneed;
if (sd.hasIdentityEquals)
goto Lneed;
/* If any of the fields has an opEquals, then we
* need it too.
*/
for (size_t i = 0; i < sd.fields.dim; i++)
{
VarDeclaration v = sd.fields[i];
if (v.storage_class & STC.ref_)
continue;
if (v.overlapped)
continue;
Type tv = v.type.toBasetype();
auto tvbase = tv.baseElemOf();
if (tvbase.ty == Tstruct)
{
TypeStruct ts = cast(TypeStruct)tvbase;
if (ts.sym.isUnionDeclaration())
continue;
if (needOpEquals(ts.sym))
goto Lneed;
if (ts.sym.aliasthis) // https://issues.dlang.org/show_bug.cgi?id=14806
goto Lneed;
}
if (tv.isfloating())
{
// This is necessray for:
// 1. comparison of +0.0 and -0.0 should be true.
// 2. comparison of NANs should be false always.
goto Lneed;
}
if (tv.ty == Tarray)
goto Lneed;
if (tv.ty == Taarray)
goto Lneed;
if (tv.ty == Tclass)
goto Lneed;
}
Ldontneed:
//printf("\tdontneed\n");
return false;
Lneed:
//printf("\tneed\n");
return true;
}
/*******************************************
* Check given aggregate actually has an identity opEquals or not.
*/
private FuncDeclaration hasIdentityOpEquals(AggregateDeclaration ad, Scope* sc)
{
Dsymbol eq = search_function(ad, Id.eq);
if (eq)
{
/* check identity opEquals exists
*/
scope er = new NullExp(ad.loc, null); // dummy rvalue
scope el = new IdentifierExp(ad.loc, Id.p); // dummy lvalue
Expressions a;
a.setDim(1);
foreach (i; 0 .. 5)
{
Type tthis = null; // dead-store to prevent spurious warning
final switch (i)
{
case 0: tthis = ad.type; break;
case 1: tthis = ad.type.constOf(); break;
case 2: tthis = ad.type.immutableOf(); break;
case 3: tthis = ad.type.sharedOf(); break;
case 4: tthis = ad.type.sharedConstOf(); break;
}
FuncDeclaration f = null;
const errors = global.startGagging(); // Do not report errors, even if the template opAssign fbody makes it.
sc = sc.push();
sc.tinst = null;
sc.minst = null;
foreach (j; 0 .. 2)
{
a[0] = (j == 0 ? er : el);
a[0].type = tthis;
f = resolveFuncCall(ad.loc, sc, eq, null, tthis, &a, FuncResolveFlag.quiet);
if (f)
break;
}
sc = sc.pop();
global.endGagging(errors);
if (f)
{
if (f.errors)
return null;
return f;
}
}
}
return null;
}
/******************************************
* Build opEquals for struct.
* const bool opEquals(const S s) { ... }
*
* By fixing https://issues.dlang.org/show_bug.cgi?id=3789
* opEquals is changed to be never implicitly generated.
* Now, struct objects comparison s1 == s2 is translated to:
* s1.tupleof == s2.tupleof
* to calculate structural equality. See EqualExp.op_overload.
*/
FuncDeclaration buildOpEquals(StructDeclaration sd, Scope* sc)
{
if (hasIdentityOpEquals(sd, sc))
{
sd.hasIdentityEquals = true;
}
return null;
}
/******************************************
* Build __xopEquals for TypeInfo_Struct
* static bool __xopEquals(ref const S p, ref const S q)
* {
* return p == q;
* }
*
* This is called by TypeInfo.equals(p1, p2). If the struct does not support
* const objects comparison, it will throw "not implemented" Error in runtime.
*/
FuncDeclaration buildXopEquals(StructDeclaration sd, Scope* sc)
{
if (!needOpEquals(sd))
return null; // bitwise comparison would work
//printf("StructDeclaration::buildXopEquals() %s\n", sd.toChars());
if (Dsymbol eq = search_function(sd, Id.eq))
{
if (FuncDeclaration fd = eq.isFuncDeclaration())
{
TypeFunction tfeqptr;
{
Scope scx;
/* const bool opEquals(ref const S s);
*/
auto parameters = new Parameters();
parameters.push(new Parameter(STC.ref_ | STC.const_, sd.type, null, null, null));
tfeqptr = new TypeFunction(ParameterList(parameters), Type.tbool, LINK.d);
tfeqptr.mod = MODFlags.const_;
tfeqptr = cast(TypeFunction)tfeqptr.typeSemantic(Loc.initial, &scx);
}
fd = fd.overloadExactMatch(tfeqptr);
if (fd)
return fd;
}
}
if (!sd.xerreq)
{
// object._xopEquals
Identifier id = Identifier.idPool("_xopEquals");
Expression e = new IdentifierExp(sd.loc, Id.empty);
e = new DotIdExp(sd.loc, e, Id.object);
e = new DotIdExp(sd.loc, e, id);
e = e.expressionSemantic(sc);
Dsymbol s = getDsymbol(e);
assert(s);
sd.xerreq = s.isFuncDeclaration();
}
Loc declLoc; // loc is unnecessary so __xopEquals is never called directly
Loc loc; // loc is unnecessary so errors are gagged
auto parameters = new Parameters();
parameters.push(new Parameter(STC.ref_ | STC.const_, sd.type, Id.p, null, null))
.push(new Parameter(STC.ref_ | STC.const_, sd.type, Id.q, null, null));
auto tf = new TypeFunction(ParameterList(parameters), Type.tbool, LINK.d);
Identifier id = Id.xopEquals;
auto fop = new FuncDeclaration(declLoc, Loc.initial, id, STC.static_, tf);
fop.generated = true;
Expression e1 = new IdentifierExp(loc, Id.p);
Expression e2 = new IdentifierExp(loc, Id.q);
Expression e = new EqualExp(TOK.equal, loc, e1, e2);
fop.fbody = new ReturnStatement(loc, e);
uint errors = global.startGagging(); // Do not report errors
Scope* sc2 = sc.push();
sc2.stc = 0;
sc2.linkage = LINK.d;
fop.dsymbolSemantic(sc2);
fop.semantic2(sc2);
sc2.pop();
if (global.endGagging(errors)) // if errors happened
fop = sd.xerreq;
return fop;
}
/******************************************
* Build __xopCmp for TypeInfo_Struct
* static bool __xopCmp(ref const S p, ref const S q)
* {
* return p.opCmp(q);
* }
*
* This is called by TypeInfo.compare(p1, p2). If the struct does not support
* const objects comparison, it will throw "not implemented" Error in runtime.
*/
FuncDeclaration buildXopCmp(StructDeclaration sd, Scope* sc)
{
//printf("StructDeclaration::buildXopCmp() %s\n", toChars());
if (Dsymbol cmp = search_function(sd, Id.cmp))
{
if (FuncDeclaration fd = cmp.isFuncDeclaration())
{
TypeFunction tfcmpptr;
{
Scope scx;
/* const int opCmp(ref const S s);
*/
auto parameters = new Parameters();
parameters.push(new Parameter(STC.ref_ | STC.const_, sd.type, null, null, null));
tfcmpptr = new TypeFunction(ParameterList(parameters), Type.tint32, LINK.d);
tfcmpptr.mod = MODFlags.const_;
tfcmpptr = cast(TypeFunction)tfcmpptr.typeSemantic(Loc.initial, &scx);
}
fd = fd.overloadExactMatch(tfcmpptr);
if (fd)
return fd;
}
}
else
{
version (none) // FIXME: doesn't work for recursive alias this
{
/* Check opCmp member exists.
* Consider 'alias this', but except opDispatch.
*/
Expression e = new DsymbolExp(sd.loc, sd);
e = new DotIdExp(sd.loc, e, Id.cmp);
Scope* sc2 = sc.push();
e = e.trySemantic(sc2);
sc2.pop();
if (e)
{
Dsymbol s = null;
switch (e.op)
{
case TOK.overloadSet:
s = (cast(OverExp)e).vars;
break;
case TOK.scope_:
s = (cast(ScopeExp)e).sds;
break;
case TOK.variable:
s = (cast(VarExp)e).var;
break;
default:
break;
}
if (!s || s.ident != Id.cmp)
e = null; // there's no valid member 'opCmp'
}
if (!e)
return null; // bitwise comparison would work
/* Essentially, a struct which does not define opCmp is not comparable.
* At this time, typeid(S).compare might be correct that throwing "not implement" Error.
* But implementing it would break existing code, such as:
*
* struct S { int value; } // no opCmp
* int[S] aa; // Currently AA key uses bitwise comparison
* // (It's default behavior of TypeInfo_Strust.compare).
*
* Not sure we should fix this inconsistency, so just keep current behavior.
*/
}
else
{
return null;
}
}
if (!sd.xerrcmp)
{
// object._xopCmp
Identifier id = Identifier.idPool("_xopCmp");
Expression e = new IdentifierExp(sd.loc, Id.empty);
e = new DotIdExp(sd.loc, e, Id.object);
e = new DotIdExp(sd.loc, e, id);
e = e.expressionSemantic(sc);
Dsymbol s = getDsymbol(e);
assert(s);
sd.xerrcmp = s.isFuncDeclaration();
}
Loc declLoc; // loc is unnecessary so __xopCmp is never called directly
Loc loc; // loc is unnecessary so errors are gagged
auto parameters = new Parameters();
parameters.push(new Parameter(STC.ref_ | STC.const_, sd.type, Id.p, null, null));
parameters.push(new Parameter(STC.ref_ | STC.const_, sd.type, Id.q, null, null));
auto tf = new TypeFunction(ParameterList(parameters), Type.tint32, LINK.d);
Identifier id = Id.xopCmp;
auto fop = new FuncDeclaration(declLoc, Loc.initial, id, STC.static_, tf);
fop.generated = true;
Expression e1 = new IdentifierExp(loc, Id.p);
Expression e2 = new IdentifierExp(loc, Id.q);
Expression e = new CallExp(loc, new DotIdExp(loc, e2, Id.cmp), e1);
fop.fbody = new ReturnStatement(loc, e);
uint errors = global.startGagging(); // Do not report errors
Scope* sc2 = sc.push();
sc2.stc = 0;
sc2.linkage = LINK.d;
fop.dsymbolSemantic(sc2);
fop.semantic2(sc2);
sc2.pop();
if (global.endGagging(errors)) // if errors happened
fop = sd.xerrcmp;
return fop;
}
/*******************************************
* We need a toHash for the struct if
* any fields has a toHash.
* Generate one if a user-specified one does not exist.
*/
private bool needToHash(StructDeclaration sd)
{
//printf("StructDeclaration::needToHash() %s\n", sd.toChars());
if (sd.isUnionDeclaration())
goto Ldontneed;
if (sd.xhash)
goto Lneed;
/* If any of the fields has an opEquals, then we
* need it too.
*/
for (size_t i = 0; i < sd.fields.dim; i++)
{
VarDeclaration v = sd.fields[i];
if (v.storage_class & STC.ref_)
continue;
if (v.overlapped)
continue;
Type tv = v.type.toBasetype();
auto tvbase = tv.baseElemOf();
if (tvbase.ty == Tstruct)
{
TypeStruct ts = cast(TypeStruct)tvbase;
if (ts.sym.isUnionDeclaration())
continue;
if (needToHash(ts.sym))
goto Lneed;
if (ts.sym.aliasthis) // https://issues.dlang.org/show_bug.cgi?id=14948
goto Lneed;
}
if (tv.isfloating())
{
/* This is necessary because comparison of +0.0 and -0.0 should be true,
* i.e. not a bit compare.
*/
goto Lneed;
}
if (tv.ty == Tarray)
goto Lneed;
if (tv.ty == Taarray)
goto Lneed;
if (tv.ty == Tclass)
goto Lneed;
}
Ldontneed:
//printf("\tdontneed\n");
return false;
Lneed:
//printf("\tneed\n");
return true;
}
/******************************************
* Build __xtoHash for non-bitwise hashing
* static hash_t xtoHash(ref const S p) nothrow @trusted;
*/
FuncDeclaration buildXtoHash(StructDeclaration sd, Scope* sc)
{
if (Dsymbol s = search_function(sd, Id.tohash))
{
__gshared TypeFunction tftohash;
if (!tftohash)
{
tftohash = new TypeFunction(ParameterList(), Type.thash_t, LINK.d);
tftohash.mod = MODFlags.const_;
tftohash = cast(TypeFunction)tftohash.merge();
}
if (FuncDeclaration fd = s.isFuncDeclaration())
{
fd = fd.overloadExactMatch(tftohash);
if (fd)
return fd;
}
}
if (!needToHash(sd))
return null;
//printf("StructDeclaration::buildXtoHash() %s\n", sd.toPrettyChars());
Loc declLoc; // loc is unnecessary so __xtoHash is never called directly
Loc loc; // internal code should have no loc to prevent coverage
auto parameters = new Parameters();
parameters.push(new Parameter(STC.ref_ | STC.const_, sd.type, Id.p, null, null));
auto tf = new TypeFunction(ParameterList(parameters), Type.thash_t, LINK.d, STC.nothrow_ | STC.trusted);
Identifier id = Id.xtoHash;
auto fop = new FuncDeclaration(declLoc, Loc.initial, id, STC.static_, tf);
fop.generated = true;
/* Do memberwise hashing.
*
* If sd is a nested struct, and if it's nested in a class, the calculated
* hash value will also contain the result of parent class's toHash().
*/
const(char)* code =
"size_t h = 0;" ~
"foreach (i, T; typeof(p.tupleof))" ~
// workaround https://issues.dlang.org/show_bug.cgi?id=17968
" static if(is(T* : const(.object.Object)*)) " ~
" h = h * 33 + typeid(const(.object.Object)).getHash(cast(const void*)&p.tupleof[i]);" ~
" else " ~
" h = h * 33 + typeid(T).getHash(cast(const void*)&p.tupleof[i]);" ~
"return h;";
fop.fbody = new CompileStatement(loc, new StringExp(loc, cast(char*)code));
Scope* sc2 = sc.push();
sc2.stc = 0;
sc2.linkage = LINK.d;
fop.dsymbolSemantic(sc2);
fop.semantic2(sc2);
sc2.pop();
//printf("%s fop = %s %s\n", sd.toChars(), fop.toChars(), fop.type.toChars());
return fop;
}
/*****************************************
* Create inclusive destructor for struct/class by aggregating
* all the destructors in dtors[] with the destructors for
* all the members.
* Params:
* ad = struct or class to build destructor for
* sc = context
* Returns:
* generated function, null if none needed
* Note:
* Close similarity with StructDeclaration::buildPostBlit(),
* and the ordering changes (runs backward instead of forwards).
*/
DtorDeclaration buildDtor(AggregateDeclaration ad, Scope* sc)
{
//printf("AggregateDeclaration::buildDtor() %s\n", ad.toChars());
if (ad.isUnionDeclaration())
return null; // unions don't have destructors
StorageClass stc = STC.safe | STC.nothrow_ | STC.pure_ | STC.nogc;
Loc declLoc = ad.dtors.dim ? ad.dtors[0].loc : ad.loc;
Loc loc; // internal code should have no loc to prevent coverage
// if the dtor is an extern(C++) prototype, then we expect it performs a full-destruction; we don't need to build a full-dtor
const bool dtorIsCppPrototype = ad.dtors.dim == 1 && ad.dtors[0].linkage == LINK.cpp && !ad.dtors[0].fbody;
if (!dtorIsCppPrototype)
{
Expression e = null;
for (size_t i = 0; i < ad.fields.dim; i++)
{
auto v = ad.fields[i];
if (v.storage_class & STC.ref_)
continue;
if (v.overlapped)
continue;
auto tv = v.type.baseElemOf();
if (tv.ty != Tstruct)
continue;
auto sdv = (cast(TypeStruct)tv).sym;
if (!sdv.dtor)
continue;
sdv.dtor.functionSemantic();
stc = mergeFuncAttrs(stc, sdv.dtor);
if (stc & STC.disable)
{
e = null;
break;
}
Expression ex;
tv = v.type.toBasetype();
if (tv.ty == Tstruct)
{
// this.v.__xdtor()
ex = new ThisExp(loc);
ex = new DotVarExp(loc, ex, v);
// This is a hack so we can call destructors on const/immutable objects.
// Do it as a type 'paint'.
ex = new CastExp(loc, ex, v.type.mutableOf());
if (stc & STC.safe)
stc = (stc & ~STC.safe) | STC.trusted;
ex = new DotVarExp(loc, ex, sdv.dtor, false);
ex = new CallExp(loc, ex);
}
else
{
// __ArrayDtor((cast(S*)this.v.ptr)[0 .. n])
const n = tv.numberOfElems(loc);
if (n == 0)
continue;
ex = new ThisExp(loc);
ex = new DotVarExp(loc, ex, v);
// This is a hack so we can call destructors on const/immutable objects.
ex = new DotIdExp(loc, ex, Id.ptr);
ex = new CastExp(loc, ex, sdv.type.pointerTo());
if (stc & STC.safe)
stc = (stc & ~STC.safe) | STC.trusted;
ex = new SliceExp(loc, ex, new IntegerExp(loc, 0, Type.tsize_t),
new IntegerExp(loc, n, Type.tsize_t));
// Prevent redundant bounds check
(cast(SliceExp)ex).upperIsInBounds = true;
(cast(SliceExp)ex).lowerIsLessThanUpper = true;
ex = new CallExp(loc, new IdentifierExp(loc, Id.__ArrayDtor), ex);
}
e = Expression.combine(ex, e); // combine in reverse order
}
/* extern(C++) destructors call into super to destruct the full hierarchy
*/
ClassDeclaration cldec = ad.isClassDeclaration();
if (cldec && cldec.classKind == ClassKind.cpp && cldec.baseClass && cldec.baseClass.primaryDtor)
{
// WAIT BUT: do I need to run `cldec.baseClass.dtor` semantic? would it have been run before?
cldec.baseClass.dtor.functionSemantic();
stc = mergeFuncAttrs(stc, cldec.baseClass.primaryDtor);
if (!(stc & STC.disable))
{
// super.__xdtor()
Expression ex = new SuperExp(loc);
// This is a hack so we can call destructors on const/immutable objects.
// Do it as a type 'paint'.
ex = new CastExp(loc, ex, cldec.baseClass.type.mutableOf());
if (stc & STC.safe)
stc = (stc & ~STC.safe) | STC.trusted;
ex = new DotVarExp(loc, ex, cldec.baseClass.primaryDtor, false);
ex = new CallExp(loc, ex);
e = Expression.combine(e, ex); // super dtor last
}
}
/* Build our own "destructor" which executes e
*/
if (e || (stc & STC.disable))
{
//printf("Building __fieldDtor(), %s\n", e.toChars());
auto dd = new DtorDeclaration(declLoc, Loc.initial, stc, Id.__fieldDtor);
dd.generated = true;
dd.storage_class |= STC.inference;
dd.fbody = new ExpStatement(loc, e);
ad.dtors.shift(dd);
ad.members.push(dd);
dd.dsymbolSemantic(sc);
ad.fieldDtor = dd;
}
}
DtorDeclaration xdtor = null;
switch (ad.dtors.dim)
{
case 0:
break;
case 1:
xdtor = ad.dtors[0];
break;
default:
assert(!dtorIsCppPrototype);
Expression e = null;
e = null;
stc = STC.safe | STC.nothrow_ | STC.pure_ | STC.nogc;
for (size_t i = 0; i < ad.dtors.dim; i++)
{
FuncDeclaration fd = ad.dtors[i];
stc = mergeFuncAttrs(stc, fd);
if (stc & STC.disable)
{
e = null;
break;
}
Expression ex = new ThisExp(loc);
ex = new DotVarExp(loc, ex, fd, false);
ex = new CallExp(loc, ex);
e = Expression.combine(ex, e);
}
auto dd = new DtorDeclaration(declLoc, Loc.initial, stc, Id.__aggrDtor);
dd.generated = true;
dd.storage_class |= STC.inference;