built-in operator candidates. Test overloading of '&' and ','.
In C++, a comma expression is an lvalue if its right-hand
subexpression is an lvalue. Update Expr::isLvalue accordingly.
llvm-svn: 59643
post-decrement, including support for generating all of the built-in
operator candidates for these operators.
C++ and C have different rules for the arguments to the builtin unary
'+' and '-'. Implemented both variants in Sema::ActOnUnaryOp.
In C++, pre-increment and pre-decrement return lvalues. Update
Expr::isLvalue accordingly.
llvm-svn: 59638
__builtin_prefetch code to only emit one diagnostic per builtin_prefetch.
While this has nothing to do with the rest of the patch, the code seemed
like overkill when I was updating it.
llvm-svn: 59588
not "int".
Fix a typo in the promotion of enumeration types that was causing some
integral promotions to look like integral conversions (leading to
extra ambiguities in overload resolution).
Check for "acceptable" overloaded operators based on the types of the
arguments. This is a somewhat odd check that is specified by the
standard, but I can't see why it actually matters: the overload
candidates it suppresses don't seem like they would ever be picked as
the best candidates.
llvm-svn: 59583
to support operators defined as member functions, e.g.,
struct X {
bool operator==(X&);
};
Overloading with non-member operators is supported, and the special
rules for the implicit object parameter (e.g., the ability for a
non-const *this to bind to an rvalue) are implemented.
This change also refactors and generalizes the code for adding
overload candidates for overloaded operator calls (C++ [over.match.expr]),
both to match the rules more exactly (name lookup of non-member
operators actually ignores member operators) and to make this routine
more reusable for the other overloaded operators.
Testing for the initialization of the implicit object parameter is
very light. More tests will come when we get support for calling
member functions directly (e.g., o.m(a1, a2)).
llvm-svn: 59564
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
function call created in response to the use of operator syntax that
resolves to an overloaded operator in C++, e.g., "str1 +
str2" that resolves to std::operator+(str1, str2)". We now build a
CXXOperatorCallExpr in C++ when we pick an overloaded operator. (But
only for binary operators, where we actually implement overloading)
I decided *not* to refactor the current CallExpr to make it abstract
(with FunctionCallExpr and CXXOperatorCallExpr as derived
classes). Doing so would allow us to make CXXOperatorCallExpr a little
bit smaller, at the cost of making the argument and callee accessors
virtual. We won't know if this is going to be a win until we can parse
lots of C++ code to determine how much memory we'll save by making
this change vs. the performance penalty due to the extra virtual
calls.
llvm-svn: 59306
functions for built-in operators, e.g., the builtin
bool operator==(int const*, int const*)
can be used for the expression "x1 == x2" given:
struct X {
operator int const*();
} x1, x2;
The scheme for handling these built-in operators is relatively simple:
for each candidate required by the standard, create a special kind of
candidate function for the built-in. If overload resolution picks the
built-in operator, we perform the appropriate conversions on the
arguments and then let the normal built-in operator take care of it.
There may be some optimization opportunity left: if we can reduce the
number of built-in operator overloads we generate, overload resolution
for these cases will go faster. However, one must be careful when
doing this: GCC generates too few operator overloads in our little
test program, and fails to compile it because none of the overloads it
generates match.
Note that we only support operator overload for non-member binary
operators at the moment. The other operators will follow.
As part of this change, ImplicitCastExpr can now be an lvalue.
llvm-svn: 59148
operators. For example, one can now write "x + y" where x or y is a
class or enumeration type, and Clang will perform overload resolution
for "+" based on the overloaded operators it finds.
The other kinds of overloadable operators in C++ will follow this same
approach.
Three major issues remain:
1) We don't find member operators
2) Since we don't have user-defined conversion operators, we can't
call any of the built-in overloaded operators in C++ [over.built].
3) Once we've done the semantic checks, we drop the overloaded
operator on the floor; it doesn't get into the AST at all.
llvm-svn: 58821
duplication in the handling of copy-initialization by constructor,
which occurs both for initialization of a declaration and for
overloading. The initialization code is due for some refactoring.
llvm-svn: 58756
ImplicitConversionSequence and, when doing so, following the specific
rules of [over.best.ics].
The computation of the implicit conversion sequences implements C++
[over.ics.ref], but we do not (yet) have ranking for implicit
conversion sequences that use reference binding.
llvm-svn: 58357
of copy initialization. Other pieces of the puzzle:
- Try/Perform-ImplicitConversion now handles implicit conversions
that don't involve references.
- Try/Perform-CopyInitialization uses
CheckSingleAssignmentConstraints for C. PerformCopyInitialization
is now used for all argument passing and returning values from a
function.
- Diagnose errors with declaring references and const values without
an initializer. (Uses a new Action callback, ActOnUninitializedDecl).
We do not yet have implicit conversion sequences for reference
binding, which means that we don't have any overloading support for
reference parameters yet.
llvm-svn: 58353
- Do not allow expressions to ever have reference type
- Extend Expr::isLvalue to handle more cases where having written a
reference into the source implies that the expression is an lvalue
(e.g., function calls, C++ casts).
- Make GRExprEngine::VisitCall treat the call arguments as lvalues when
they are being bound to a reference parameter.
llvm-svn: 58306
- CastExpr is the root of all casts
- ImplicitCastExpr is (still) used for all explicit casts
- ExplicitCastExpr is now the root of all *explicit* casts
- ExplicitCCastExpr (new name needed!?) is a C-style cast in C or C++
- CXXFunctionalCastExpr inherits from ExplicitCastExpr
- CXXNamedCastExpr inherits from ExplicitCastExpr and is the root of all
of the C++ named cast expression types (static_cast, dynamic_cast, etc.)
- Added classes CXXStaticCastExpr, CXXDynamicCastExpr,
CXXReinterpretCastExpr, and CXXConstCastExpr to
Also, fixed returned-stack-addr.cpp, which broke once when we fixed
reinterpret_cast to diagnose double->int* conversions and again when
we eliminated implicit conversions to reference types. The fix is in
both testcase and SemaChecking.cpp.
Most of this patch is simply support for the renaming. There's very
little actual change in semantics.
llvm-svn: 58264
There is still a bug here (as the FIXME in the test case indicates). Prior to this patch, the bug would generate an error. Now, we simply do nothing (which is less harmful until we can get it right). The complete bug fix will require changing ASTContext::mergeTypes(), which I'd like to defer for now.
llvm-svn: 58241
conversions.
Added PerformImplicitConversion, which follows an implicit conversion sequence
computed by TryCopyInitialization and actually performs the implicit
conversions, including the extra check for ambiguity mentioned above.
llvm-svn: 58071
Changes:
- Sema::IsQualificationConversion determines whether we have a qualification
conversion.
- Sema::CheckSingleAssignment constraints now follows the C++ rules in C++,
performing an implicit conversion from the right-hand side to the type of
the left-hand side rather than checking based on the C notion of
"compatibility". We now rely on the implicit-conversion code to
determine whether the conversion can happen or
not. Sema::TryCopyInitialization has an ugly reference-related
hack to cope with the initialization of references, for now.
- When building DeclRefExprs, strip away the reference type, since
there are no expressions whose type is a reference. We'll need to
do this throughout Sema.
- Expr::isLvalue now permits functions to be lvalues in C++ (but not
in C).
llvm-svn: 57935
