This takes some trickery since CastExpr has subclasses (and indeed,
is abstract).
Also, smoosh the CastKind into the bitfield from Expr.
Drops two words of storage from Expr in the common case of expressions
which don't need inheritance paths. Avoids a separate allocation and
another word of overhead in cases needing inheritance paths. Also has
the advantage of not leaking memory, since destructors for AST nodes are
never run.
llvm-svn: 110507
size" error for code like
new (int [size])
to a warning, add a Fix-It to remove the parentheses, and make this
diagnostic work properly when it occurs in a template
instantiation. <rdar://problem/8018245>.
llvm-svn: 108242
Before this commit, sub-stmts were stored as encountered and when they were placed in the Stmts stack we had to know what index
each stmt operand has. This complicated supporting variable sub-stmts and sub-stmts that were contained in TypeSourceInfos, e.g.
x = sizeof(int[1]);
would crash PCH.
Now, sub-stmts are stored in reverse order, from last to first, so that when reading them, in order to get the next sub-stmt we just
need to pop the last stmt from the stack. This greatly simplified the way stmts are written and read (just use PCHWriter::AddStmt and
PCHReader::ReadStmt accordingly) and allowed variable stmt operands and TypeSourceInfo exprs.
llvm-svn: 107087
if/while/switch/for statements to ensure that walking the children of
these statements actually works. Previously, we stored the condition
variable as a VarDecl. However, StmtIterator isn't able to walk from a
VarDecl to a set of statements, and would (in some circumstances) walk
beyond the end of the list of statements, cause Bad Behavior.
In this change, we've gone back to representing the condition
variables as DeclStmts. While not as memory-efficient as VarDecls, it
greatly simplifies iteration over the children.
Fixes the remainder of <rdar://problem/8104754>.
llvm-svn: 106504
return value optimization. Sema marks return statements with their
NRVO candidates (which may or may not end up using the NRVO), then, at
the end of a function body, computes and marks those variables that
can be allocated into the return slot.
I've checked this locally with some debugging statements (not
committed), but there won't be any tests until CodeGen comes along.
llvm-svn: 103865
"return" statement and mark the corresponding CXXConstructExpr as
elidable. Teach CodeGen that eliding a temporary is different from
eliding an object construction.
This is just a baby step toward NRVO.
llvm-svn: 103849
classes, since we only warn (not error) on offsetof() for non-POD
types. We store the base path within the OffsetOfExpr itself, then
evaluate the offsets within the constant evaluator.
llvm-svn: 102571
Amadini.
This change introduces a new expression node type, OffsetOfExpr, that
describes __builtin_offsetof. Previously, __builtin_offsetof was
implemented using a unary operator whose subexpression involved
various synthesized array-subscript and member-reference expressions,
which was ugly and made it very hard to instantiate as a
template. OffsetOfExpr represents the AST more faithfully, with proper
type source information and a more compact representation.
OffsetOfExpr also has support for dependent __builtin_offsetof
expressions; it can be value-dependent, but will never be
type-dependent (like sizeof or alignof). This commit introduces
template instantiation for __builtin_offsetof as well.
There are two major caveats to this patch:
1) CodeGen cannot handle the case where __builtin_offsetof is not a
constant expression, so it produces an error. So, to avoid
regressing in C, we retain the old UnaryOperator-based
__builtin_offsetof implementation in C while using the shiny new
OffsetOfExpr implementation in C++. The old implementation can go
away once we have proper CodeGen support for this case, which we
expect won't cause much trouble in C++.
2) __builtin_offsetof doesn't work well with non-POD class types,
particularly when the designated field is found within a base
class. I will address this in a subsequent patch.
Fixes PR5880 and a bunch of assertions when building Boost.Python
tests.
llvm-svn: 102542
statements. Instead of the @try having a single @catch, where all of
the @catch's were chained (using an O(n^2) algorithm nonetheless),
@try just holds an array of its @catch blocks. The resulting AST is
slightly more compact (not important) and better represents the actual
language semantics (good).
llvm-svn: 102221
expressions, to improve source-location information, clarify the
actual receiver of the message, and pave the way for proper C++
support. The ObjCMessageExpr node represents four different kinds of
message sends in a single AST node:
1) Send to a object instance described by an expression (e.g., [x method:5])
2) Send to a class described by the class name (e.g., [NSString method:5])
3) Send to a superclass class (e.g, [super method:5] in class method)
4) Send to a superclass instance (e.g., [super method:5] in instance method)
Previously these four cases where tangled together. Now, they have
more distinct representations. Specific changes:
1) Unchanged; the object instance is represented by an Expr*.
2) Previously stored the ObjCInterfaceDecl* referring to the class
receiving the message. Now stores a TypeSourceInfo* so that we know
how the class was spelled. This both maintains typedef information
and opens the door for more complicated C++ types (e.g., dependent
types). There was an alternative, unused representation of these
sends by naming the class via an IdentifierInfo *. In practice, we
either had an ObjCInterfaceDecl *, from which we would get the
IdentifierInfo *, or we fell into the case below...
3) Previously represented by a class message whose IdentifierInfo *
referred to "super". Sema and CodeGen would use isStr("super") to
determine if they had a send to super. Now represented as a
"class super" send, where we have both the location of the "super"
keyword and the ObjCInterfaceDecl* of the superclass we're
targetting (statically).
4) Previously represented by an instance message whose receiver is a
an ObjCSuperExpr, which Sema and CodeGen would check for via
isa<ObjCSuperExpr>(). Now represented as an "instance super" send,
where we have both the location of the "super" keyword and the
ObjCInterfaceDecl* of the superclass we're targetting
(statically). Note that ObjCSuperExpr only has one remaining use in
the AST, which is for "super.prop" references.
The new representation of ObjCMessageExpr is 2 pointers smaller than
the old one, since it combines more storage. It also eliminates a leak
when we loaded message-send expressions from a precompiled header. The
representation also feels much cleaner to me; comments welcome!
This patch attempts to maintain the same semantics we previously had
with Objective-C message sends. In several places, there are massive
changes that boil down to simply replacing a nested-if structure such
as:
if (message has a receiver expression) {
// instance message
if (isa<ObjCSuperExpr>(...)) {
// send to super
} else {
// send to an object
}
} else {
// class message
if (name->isStr("super")) {
// class send to super
} else {
// send to class
}
}
with a switch
switch (E->getReceiverKind()) {
case ObjCMessageExpr::SuperInstance: ...
case ObjCMessageExpr::Instance: ...
case ObjCMessageExpr::SuperClass: ...
case ObjCMessageExpr::Class:...
}
There are quite a few places (particularly in the checkers) where
send-to-super is effectively ignored. I've placed FIXMEs in most of
them, and attempted to address send-to-super in a reasonable way. This
could use some review.
llvm-svn: 101972
