This allows clang to use the backend parameter attribute 'returned' when generating 'this'-returning constructors and destructors in ARM and MSVC C++ ABIs.
llvm-svn: 185291
This function only makes sense there. Eventually it should no longer
be part of the CGCXXABI interface, as it is an Itanium-specific detail.
Differential Revision: http://llvm-reviews.chandlerc.com/D821
llvm-svn: 185213
1) Removed useless return value of CGCXXABI::EmitConstructorCall and CGCXXABI::EmitVirtualDestructorCall and implementations
2) Corrected last portion of CodeGenCXX/constructor-destructor-return-this to correctly test for non-'this'-return of virtual destructor calls
llvm-svn: 184330
In Itanium, dynamic classes have one vtable with several different
address points for dynamic base classes that can't share vtables.
In the MS C++ ABI, each vbtable that can't be shared gets its own
symbol, similar to how ctor vtables work in Itanium. However, instead
of mangling the subobject offset into the symbol, the unique portions of
the inheritance path are mangled into the symbol to make it unique.
This patch implements the MSVC 2012 scheme for forming unique vbtable
symbol names. MSVC 2010 use the same mangling with a different subset
of the path. Implementing that mangling and possibly others is TODO.
Each vbtable is an array of i32 offsets from the vbptr that points to it
to another virtual base subobject. The first entry of a vbtable always
points to the base of the current subobject, implying that it is the
same no matter which parent class contains it.
Reviewers: rjmccall
Differential Revision: http://llvm-reviews.chandlerc.com/D636
llvm-svn: 184309
The backend will now use the generic 'returned' attribute to form tail calls where possible, as well as avoid save-restores of 'this' in some cases (specifically the cases that matter for the ARM C++ ABI).
This patch also reverts a prior front-end only partial implementation of these optimizations, since it's no longer required.
llvm-svn: 184205
While we can't yet emit vbtables, this allows us to find virtual bases
of objects constructed in other TUs.
This make iostream hello world work, since basic_ostream virtually
inherits from basic_ios.
Differential Revision: http://llvm-reviews.chandlerc.com/D795
llvm-svn: 182870
Summary:
This only supports converting along non-virtual inheritance paths by
changing the field offset or the non-virtual base adjustment.
This implements three kinds of conversions:
- codegen for Value conversions
- Constant emission for APValue
- Constant folding for CastExprs
In almost all constant initialization settings
EmitMemberPointer(APValue) is called, except when the expression
contains a reinterpret cast.
reinterpret casts end up being a big corner case because the null value
changes between different kinds of member pointers.
Reviewers: rsmith
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D741
llvm-svn: 181543
Also,
- abstract out the indirect/in memory/in registers decisions into the CGCXXABI
- fix handling of empty struct arguments for '-cxx-abi microsoft'
- add/fix tests
llvm-svn: 179681
non-constant constructors or non-trivial destructors. Plus bugfixes for
thread_local references bound to temporaries (the temporaries themselves are
lifetime-extended to become thread_local), and the corresponding case for
std::initializer_list.
llvm-svn: 179496
Summary:
For non-dynamic classes (no virtual bases), member data pointers are
simple offsets from the base of the record. Dynamic classes use an
aggregate for member data pointers and are therefore currently
unsupported.
Unlike Itanium, the ms ABI uses 0 to represent null for polymorphic
classes. Non-polymorphic classes use -1 like Itanium, since 0 is a
valid field offset.
Reviewers: rjmccall
CC: timurrrr, cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D558
llvm-svn: 177753
For constructors/desctructors that return 'this', if there exists a callsite
that returns 'this' and is immediately before the return instruction, make
sure we are using the return value from the callsite.
We don't need to keep 'this' alive through the callsite. It also enables
optimizations in the backend, such as tail call optimization.
Updated from r177211.
rdar://12818789
llvm-svn: 177541
For constructors/desctructors that return 'this', if there exists a callsite
that returns 'this' and is immediately before the return instruction, make
sure we are using the return value from the callsite.
We don't need to keep 'this' alive through the callsite. It also enables
optimizations in the backend, such as tail call optimization.
rdar://12818789
llvm-svn: 177211
never key functions. We did not implement that rule for the
iOS ABI, which was driven by what was implemented in gcc-4.2.
However, implement it now for other ARM-based platforms.
llvm-svn: 173515
uncovered.
This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.
I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.
llvm-svn: 169237
This is consistent/interoperable with GCC 4.7 (& __cxa_deleted_function isn't
present in 4.4 - not sure when it got added, but you'll need something with
that function available for this to work).
llvm-svn: 166069
be sure to delete the complete object pointer, not the original
pointer. This is necessary if the base being deleted is at a
non-zero offset in the complete object. This is only required
for objects with virtual destructors because deleting an object
via a base-class subobject when the base does not have a virtual
destructor is undefined behavior.
Noticed while reviewing the last four years of cxx-abi-dev
activity.
llvm-svn: 164597
and only consider using __cxa_atexit in the Itanium logic. The
default logic is to use atexit().
Emit "guarded" initializers in Microsoft mode unconditionally.
This is definitely not correct, but it's closer to correct than
just not emitting the initializer.
Based on a patch by Timur Iskhodzhanov!
llvm-svn: 155894
what I'm going to treat as basically universal properties of
array-cookie code. Implement MS array cookies on top of that.
Based on a patch by Timur Iskhodzhanov!
llvm-svn: 155886
These patches cause us to miscompile and/or reject code with static
function-local variables in an extern-C context. Previously, we were
papering over this as long as the variables are within the same
translation unit, and had not seen any failures in the wild. We still
need a proper fix, which involves mangling static locals inside of an
extern-C block (as GCC already does), but this patch causes pretty
widespread regressions. Firefox, and many other applications no longer
build.
Lots of test cases have been posted to the list in response to this
commit, so there should be no problem reproducing the issues.
llvm-svn: 153768
is general goodness because representations of member pointers are
not always equivalent across member pointer types on all ABIs
(even though this isn't really standard-endorsed).
Take advantage of the new information to teach IR-generation how
to do these reinterprets in constant initializers. Make sure this
works when intermingled with hierarchy conversions (although
this is not part of our motivating use case). Doing this in the
constant-evaluator would probably have been better, but that would
require a *lot* of extra structure in the representation of
constant member pointers: you'd really have to track an arbitrary
chain of hierarchy conversions and reinterpretations in order to
get this right. Ultimately, this seems less complex. I also
wasn't quite sure how to extend the constant evaluator to handle
foldings that we don't actually want to treat as extended
constant expressions.
llvm-svn: 150551
constructor, and that constructor is used to initialize an object of static
storage duration such that all members and bases are initialized by constant
expressions, constant initialization is performed. In this case, the object
can still have a non-trivial destructor, and if it does, we must emit a dynamic
initializer which performs no initialization and instead simply registers that
destructor.
llvm-svn: 150419
APValue::Array and APValue::MemberPointer. All APValue values can now be emitted
as constants.
Add new CGCXXABI entry point for emitting an APValue MemberPointer. The other
entrypoints dealing with constant member pointers are no longer necessary and
will be removed in a later change.
Switch codegen from using EvaluateAsRValue/EvaluateAsLValue to
VarDecl::evaluateValue. This performs caching and deals with the nasty cases in
C++11 where a non-const object's initializer can refer indirectly to
previously-initialized fields within the same object.
Building the intermediate APValue object incurs a measurable performance hit on
pathological testcases with huge initializer lists, so we continue to build IR
directly from the Expr nodes for array and record types outside of C++11.
llvm-svn: 148178
for __unknown_anytype resolution to destructively modify the AST. So that's
what it does now, which significantly simplifies some of the implementation.
Normal member calls work pretty cleanly now, and I added support for
propagating unknown-ness through &.
llvm-svn: 129331
right for anonymous struct/union members led to me discovering some
seemingly broken code in that area of Sema, which I fixed, partly by
changing the representation of member pointer constants so that
IndirectFieldDecls aren't expanded. This led to assorted cleanups with
member pointers in CodeGen, and while I was doing that I saw some random
other things to clean up.
llvm-svn: 124785
deallocation function has a two-argument form. Store the result of this
check in new[] and delete[] nodes.
Fixes rdar://problem/8913519
llvm-svn: 124373
process, perform a number of refactorings:
- Move MiscNameMangler member functions to MangleContext
- Remove GlobalDecl dependency from MangleContext
- Make MangleContext abstract and move Itanium/Microsoft functionality
to their own classes/files
- Implement ASTContext::createMangleContext and have CodeGen use it
No (intended) functionality change.
llvm-svn: 123386
data members by delaying the emission of the initializer until after
linkage and visibility have been set on the global. Also, don't
emit a guard unless the variable actually ends up with vague linkage,
and don't use thread-safe statics in any case.
llvm-svn: 118336
implement ARM array cookies. Also fix a few unfortunate bugs:
- throwing dtors in deletes prevented the allocation from being deleted
- adding the cookie to the new[] size was not being considered for
overflow (and, more seriously, was screwing up the earlier checks)
- deleting an array via a pointer to array of class type was not
causing any destructors to be run and was passing the unadjusted
pointer to the deallocator
- lots of address-space problems, in case anyone wants to support
free store in a variant address space :)
llvm-svn: 112814
Stephen Lin