system. Since C99 doesn't have overloading and C++ doesn't have
_Complex, there is no specification for this. Here's what I think
makes sense.
Complex conversions come in several flavors:
- Complex promotions: a complex -> complex conversion where the
underlying real-type conversion is a floating-point promotion. GCC
seems to call this a promotion, EDG does something else. This is
given "promotion" rank for determining the best viable function.
- Complex conversions: a complex -> complex conversion that is
not a complex promotion. This is given "conversion" rank for
determining the best viable function.
- Complex-real conversions: a real -> complex or complex -> real
conversion. This is given "conversion" rank for determining the
best viable function.
These rules are the same for C99 (when using the "overloadable"
attribute) and C++. However, there is one difference in the handling
of floating-point promotions: in C99, float -> long double and double
-> long double are considered promotions (so we give them "promotion"
rank), while C++ considers these conversions ("conversion" rank).
llvm-svn: 64343
This commit adds a new attribute, "overloadable", that enables C++
function overloading in C. The attribute can only be added to function
declarations, e.g.,
int *f(int) __attribute__((overloadable));
If the "overloadable" attribute exists on a function with a given
name, *all* functions with that name (and in that scope) must have the
"overloadable" attribute. Sets of overloaded functions with the
"overloadable" attribute then follow the normal C++ rules for
overloaded functions, e.g., overloads must have different
parameter-type-lists from each other.
When calling an overloaded function in C, we follow the same
overloading rules as C++, with three extensions to the set of standard
conversions:
- A value of a given struct or union type T can be converted to the
type T. This is just the identity conversion. (In C++, this would
go through a copy constructor).
- A value of pointer type T* can be converted to a value of type U*
if T and U are compatible types. This conversion has Conversion
rank (it's considered a pointer conversion in C).
- A value of type T can be converted to a value of type U if T and U
are compatible (and are not both pointer types). This conversion
has Conversion rank (it's considered to be a new kind of
conversion unique to C, a "compatible" conversion).
Known defects (and, therefore, next steps):
1) The standard-conversion handling does not understand conversions
involving _Complex or vector extensions, so it is likely to get
these wrong. We need to add these conversions.
2) All overloadable functions with the same name will have the same
linkage name, which means we'll get a collision in the linker (if
not sooner). We'll need to mangle the names of these functions.
llvm-svn: 64336
- Made allocation of Stmt objects using vanilla new/delete a *compiler
error* by making this new/delete "protected" within class Stmt.
- Now the only way to allocate Stmt objects is by using the new
operator that takes ASTContext& as an argument. This ensures that
all Stmt nodes are allocated from the same (pool) allocator.
- Naturally, these two changes required that *all* creation sites for
AST nodes use new (ASTContext&). This is a large patch, but the
majority of the changes are just this mechanical adjustment.
- The above changes also mean that AST nodes can no longer be
deallocated using 'delete'. Instead, one most do
StmtObject->Destroy(ASTContext&) or do
ASTContextObject.Deallocate(StmtObject) (the latter not running the
'Destroy' method).
Along the way I also...
- Made CompoundStmt allocate its array of Stmt* using the allocator in
ASTContext (previously it used std::vector). There are a whole
bunch of other Stmt classes that need to be similarly changed to
ensure that all memory allocated for ASTs comes from the allocator
in ASTContext.
- Added a new smart pointer ExprOwningPtr to Sema.h. This replaces
the uses of llvm::OwningPtr within Sema, as llvm::OwningPtr used
'delete' to free memory instead of a Stmt's 'Destroy' method.
Big thanks to Doug Gregor for helping with the acrobatics of making
'new/delete' private and the new smart pointer ExprOwningPtr!
llvm-svn: 63997
unqualified-id '('
in C++. The unqualified-id might not refer to any declaration in our
current scope, but declarations by that name might be found via
argument-dependent lookup. We now do so properly.
As part of this change, CXXDependentNameExpr, which was previously
designed to express the unqualified-id in the above constructor within
templates, has become UnresolvedFunctionNameExpr, which does
effectively the same thing but will work for both templates and
non-templates.
Additionally, we cope with all unqualified-ids, since ADL also applies
in cases like
operator+(x, y)
llvm-svn: 63733
LookupName et al. Instead, use an enum and a bool to describe its
contents.
Optimized the C/Objective-C path through LookupName, eliminating any
unnecessarily C++isms. Simplify IdentifierResolver::iterator, removing
some code and arguments that are no longer used.
Eliminated LookupDeclInScope/LookupDeclInContext, moving all callers
over to LookupName, LookupQualifiedName, or LookupParsedName, as
appropriate.
All together, I'm seeing a 0.2% speedup on Cocoa.h with PTH and
-disable-free. Plus, we're down to three name-lookup routines.
llvm-svn: 63354
The previous interface was very confusing. This is much more explicit, which will be easier to understand/optimize/convert.
The plan is to eventually deprecate both of these functions. For now, I'm focused on performance.
llvm-svn: 63256
Even though Sema::LookupDecl() is deprecated, it's still used all over the place. Simplifying the interface will make it easier to understand/optimize/convert.
llvm-svn: 63210
.def file for each library. This means that adding a diagnostic
to sema doesn't require all the other libraries to be rebuilt.
Patch by Anders Johnsen!
llvm-svn: 63111
that every declaration lives inside a DeclContext.
Moved several things that don't have names but were ScopedDecls (and,
therefore, NamedDecls) to inherit from Decl rather than NamedDecl,
including ObjCImplementationDecl and LinkageSpecDecl. Now, we don't
store empty DeclarationNames for these things, nor do we try to insert
them into DeclContext's lookup structure.
The serialization tests are temporarily disabled. We'll re-enable them
once we've sorted out the remaining ownership/serialiazation issues
between DeclContexts and TranslationUnion, DeclGroups, etc.
llvm-svn: 62562
new DiagnoseIncompleteType. It provides additional information about
struct/class/union/enum types when possible, either by pointing to the
forward declaration of that type or by pointing to the definition (if
we're in the process of defining that type).
Fixes <rdar://problem/6500531>.
llvm-svn: 62521
analysis and AST-building for the cases where we have N != 1
arguments. For N == 1 arguments, we need to finish the C++
implementation of explicit type casts (C++ [expr.cast]).
llvm-svn: 62329
This change refactors and cleans up our handling of name lookup with
LookupDecl. There are several aspects to this refactoring:
- The criteria for name lookup is now encapsulated into the class
LookupCriteria, which replaces the hideous set of boolean values
that LookupDecl currently has.
- The results of name lookup are returned in a new class
LookupResult, which can lazily build OverloadedFunctionDecls for
overloaded function sets (and, eventually, eliminate the need to
allocate member for OverloadedFunctionDecls) and contains a
placeholder for handling ambiguous name lookup (for C++).
- The primary entry points for name lookup are now LookupName (for
unqualified name lookup) and LookupQualifiedName (for qualified
name lookup). There is also a convenience function
LookupParsedName that handles qualified/unqualified name lookup
when given a scope specifier. Together, these routines are meant
to gradually replace the kludgy LookupDecl, but this won't happen
until after we have base class lookup (which forces us to cope
with ambiguities).
- Documented the heck out of name lookup. Experimenting a little
with using Doxygen's member groups to make some sense of the Sema
class. Feedback welcome!
- Fixes some lingering issues with name lookup for
nested-name-specifiers, which now goes through
LookupName/LookupQualifiedName.
llvm-svn: 62245
Small cleanup in the handling of user-defined conversions.
Also, implement an optimization when constructing a call. We avoid
recomputing implicit conversion sequences and instead use those
conversion sequences that we computed as part of overload resolution.
llvm-svn: 62231
- ObjCContainerDecl's (ObjCInterfaceDecl/ObjCCategoryDecl/ObjCProtocolDecl), ObjCCategoryImpl, & ObjCImplementation are all DeclContexts.
- ObjCMethodDecl is now a ScopedDecl (so it can play nicely with DeclContext).
- ObjCContainerDecl now does iteration/lookup using DeclContext infrastructure (no more linear search:-)
- Removed ASTContext argument to DeclContext::lookup(). It wasn't being used and complicated it's use from an ObjC AST perspective.
- Added Sema::ProcessPropertyDecl() and removed Sema::diagnosePropertySetterGetterMismatch().
- Simplified Sema::ActOnAtEnd() considerably. Still more work to do.
- Fixed an incorrect casting assumption in Sema::getCurFunctionOrMethodDecl(), now that ObjCMethodDecl is a ScopedDecl.
- Removed addPropertyMethods from ObjCInterfaceDecl/ObjCCategoryDecl/ObjCProtocolDecl.
This passes all the tests on my machine. Since many of the changes are central to the way ObjC finds it's methods, I expect some fallout (and there are still a handful of FIXME's). Nevertheless, this should be a step in the right direction.
llvm-svn: 61929
Make C++ classes track the POD property (C++ [class]p4)
Track the existence of a copy assignment operator.
Implicitly declare the copy assignment operator if none is provided.
Implement most of the parsing job for the G++ type traits extension.
Fully implement the low-hanging fruit of the type traits:
__is_pod: Whether a type is a POD.
__is_class: Whether a type is a (non-union) class.
__is_union: Whether a type is a union.
__is_enum: Whether a type is an enum.
__is_polymorphic: Whether a type is polymorphic (C++ [class.virtual]p1).
llvm-svn: 61746
attached to an identifier. Instead, all overloaded functions will be
pushed into scope, and we'll synthesize an OverloadedFunctionDecl on
the fly when we need it.
llvm-svn: 61386
DeclContext. Instead, just keep the list of currently-active
declarations and only build the OverloadedFunctionDecl when we
absolutely need it.
This is a half-step toward eliminating the need to explicitly build
OverloadedFunctionDecls that store sets of overloaded
functions. This was suggested by Argiris a while back, and it's a good
thing for several reasons: first, it eliminates the messy logic that
currently tries to keep the OverloadedFunctionDecl in sync with the
declarations that are being added. Second, it will (eventually)
eliminate the need to allocate memory for overload sets, which could
help performance. Finally, it helps set us up for when name lookup can
return multiple (possibly ambiguous) results, as can happen with
lookup of class members in C++.
Next steps: make the IdentifierResolver store overloads as separate
entries in its list rather than replacing them with an
OverloadedFunctionDecl now, then see how far we can go toward
eliminating OverloadedFunctionDecl entirely.
llvm-svn: 61357
and separates lexical name lookup from qualified name lookup. In
particular:
* Make DeclContext the central data structure for storing and
looking up declarations within existing declarations, e.g., members
of structs/unions/classes, enumerators in C++0x enums, members of
C++ namespaces, and (later) members of Objective-C
interfaces/implementations. DeclContext uses a lazily-constructed
data structure optimized for fast lookup (array for small contexts,
hash table for larger contexts).
* Implement C++ qualified name lookup in terms of lookup into
DeclContext.
* Implement C++ unqualified name lookup in terms of
qualified+unqualified name lookup (since unqualified lookup is not
purely lexical in C++!)
* Limit the use of the chains of declarations stored in
IdentifierInfo to those names declared lexically.
* Eliminate CXXFieldDecl, collapsing its behavior into
FieldDecl. (FieldDecl is now a ScopedDecl).
* Make RecordDecl into a DeclContext and eliminates its
Members/NumMembers fields (since one can just iterate through the
DeclContext to get the fields).
llvm-svn: 60878
"else" clause, e.g.,
if (int X = foo()) {
} else {
if (X) { // warning: X is always zero in this context
}
}
Fixes rdar://6425550 and lets me think about something other than
DeclContext.
llvm-svn: 60858
expressions, and value-dependent expressions. This permits us to parse
some template definitions.
This is not a complete solution; we're missing type- and
value-dependent computations for most of the expression types, and
we're missing checks for dependent types and type-dependent
expressions throughout Sema.
llvm-svn: 60615
instead of converting them to strings first. This also fixes a
bunch of minor inconsistencies in the diagnostics emitted by clang
and adds a bunch of FIXME's to DiagnosticKinds.def.
llvm-svn: 59948
uses of getName() with uses of getDeclName(). This upgrades a bunch of
diags to take DeclNames instead of std::strings.
This also tweaks a couple of diagnostics to be cleaner and changes
CheckInitializerTypes/PerformInitializationByConstructor to pass
around DeclarationNames instead of std::strings.
llvm-svn: 59947
of doing the lookup_decl, the hash lookup is cheap. Also,
typeid doesn't happen enough in real world code to worry about
it.
I'd like to eventually get rid of KnownFunctionIDs from Sema
also, but today is not that day.
llvm-svn: 59711
DeclRefExprs and BlockDeclRefExprs into a single function
Sema::ActOnDeclarationNameExpr, eliminating a bunch of duplicate
lookup-name-and-check-the-result code.
Note that we still have the three parser entry points for identifiers,
operator-function-ids, and conversion-function-ids, since the parser
doesn't (and shouldn't) know about DeclarationNames. This is a Good
Thing (TM), and there will be more entrypoints coming (e.g., for C++
pseudo-destructor expressions).
llvm-svn: 59527
operator+, directly, using the same mechanism as all other special
names.
Removed the "special" identifiers for the overloaded operators from
the identifier table and IdentifierInfo data structure. IdentifierInfo
is back to representing only real identifiers.
Added a new Action, ActOnOperatorFunctionIdExpr, that builds an
expression from an parsed operator-function-id (e.g., "operator
+"). ActOnIdentifierExpr used to do this job, but
operator-function-ids are no longer represented by IdentifierInfo's.
Extended Declarator to store overloaded operator names.
Sema::GetNameForDeclarator now knows how to turn the operator
name into a DeclarationName for the overloaded operator.
Except for (perhaps) consolidating the functionality of
ActOnIdentifier, ActOnOperatorFunctionIdExpr, and
ActOnConversionFunctionExpr into a common routine that builds an
appropriate DeclRefExpr by looking up a DeclarationName, all of the
work on normalizing declaration names should be complete with this
commit.
llvm-svn: 59526
C++ constructors, destructors, and conversion functions now have a
FETokenInfo field that IdentifierResolver can access, so that these
special names are handled just like ordinary identifiers. A few other
Sema routines now use DeclarationNames instead of IdentifierInfo*'s.
To validate this design, this code also implements parsing and
semantic analysis for id-expressions that name conversion functions,
e.g.,
return operator bool();
The new parser action ActOnConversionFunctionExpr takes the result of
parsing "operator type-id" and turning it into an expression, using
the IdentifierResolver with the DeclarationName of the conversion
function. ActOnDeclarator pushes those conversion function names into
scope so that the IdentifierResolver can find them, of course.
llvm-svn: 59462
Douglas Gregor