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
After some discussion, it was decided to use the Itanium ABI for thread_local on
Darwin OS X platforms. This involved a couple of changes. First, we use
"_tlv_atexit" instead of "__cxa_thread_atexit". Secondly, the global variables
are marked with 'internal' linkage, because we want all access to be calls to
the Itanium-specific entry point, which has normal linkage.
<rdar://problem/13733006>
llvm-svn: 180941
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
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
calls and declarations.
LLVM has a default CC determined by the target triple. This is
not always the actual default CC for the ABI we've been asked to
target, and so we sometimes find ourselves annotating all user
functions with an explicit calling convention. Since these
calling conventions usually agree for the simple set of argument
types passed to most runtime functions, using the LLVM-default CC
in principle has no effect. However, the LLVM optimizer goes
into histrionics if it sees this kind of formal CC mismatch,
since it has no concept of CC compatibility. Therefore, if this
module happens to define the "runtime" function, or got LTO'ed
with such a definition, we can miscompile; so it's quite
important to get this right.
Defining runtime functions locally is quite common in embedded
applications.
llvm-svn: 176286
In cooperation with the LLVM patch, this should implement all scalar front-end
parts of the C and C++ ABIs for AArch64.
This patch excludes the NEON support also reviewed due to an outbreak of
batshit insanity in our legal department. That will be committed soon bringing
the changes to precisely what has been approved.
Further reviews would be gratefully received.
llvm-svn: 174055
Several places were still treating the Attribute object as respresenting
multiple attributes. Those places now use the AttributeSet to represent
multiple attributes.
llvm-svn: 174004
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
Convert the uses of the Attributes class over to the new format. The
Attributes::get method call now takes an LLVM context so that the attributes
object can be uniquified and stored.
llvm-svn: 165918
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
the function body, but do so in a way that doesn't make any assumptions
about the static local actually having a proper, unique mangling,
since apparently we don't do that correctly at all.
llvm-svn: 153776
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
the case that the variable already exists. Partly this is just
protection against people making crazy declarations with custom
asm labels or extern "C" names that intentionally collide with
the manglings of such variables, but the main reason is that we
can actually emit a static local variable twice with the
requirement that it match up. There may be other cases with
(e.g.) the various nested functions, but the main exemplar is
with constructor variants, where we can be forced into
double-emitting the function body under certain circumstances
like (currently) the presence of virtual bases.
llvm-svn: 153723
optional argument passed through the variadic ellipsis)
potentially affects how we need to lower it. Propagate
this information down to the various getFunctionInfo(...)
overloads on CodeGenTypes. Furthermore, rename those
overloads to clarify their distinct purposes, and make
sure we're calling the right one in the right place.
This has a nice side-effect of making it easier to construct
a function type, since the 'variadic' bit is no longer
separable.
This shouldn't really change anything for our existing
platforms, with one minor exception --- we should now call
variadic ObjC methods with the ... in the "right place"
(see the test case), which I guess matters for anyone
running GNUStep on MIPS. Mostly it's just a substantial
clean-up.
llvm-svn: 150788
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
Stephen Lin