Now the GEP constant utility functions require the type to be explicitly
passed (since eventually the pointer type will be opaque and not convey
the required type information). For now callers can still pass nullptr
(though none were needed here in Clang, which is nice) if
convenienc/necessary, but eventually that will be disallowed as well.
llvm-svn: 233937
Utilizing IMAGEREL relocations for synthetic IR constructs isn't
valuable, just clutter. While we are here, simplify HandlerType names
by making the numeric value for the 'adjective' part of the mangled name
instead of appending '.const', etc. The old scheme made for very long
global names and leads to wordy things like '.std_bad_alloc'
llvm-svn: 233503
There are no widely deployed standard libraries providing sized
deallocation functions, so we have to punt and ask the user if they want
us to use sized deallocation. In the future, when such libraries are
deployed, we can teach the driver to detect them and enable this
feature.
N3536 claimed that a weak thunk from sized to unsized deallocation could
be emitted to avoid breaking backwards compatibility with standard
libraries not providing sized deallocation. However, this approach and
other variations don't work in practice.
With the weak function approach, the thunk has to have default
visibility in order to ensure that it is overridden by other DSOs
providing sized deallocation. Weak, default visibility symbols are
particularly expensive on MachO, so John McCall was considering
disabling this feature by default on Darwin. It also changes behavior
ELF linking behavior, causing certain otherwise unreferenced object
files from an archive to be pulled into the link.
Our second approach was to use an extern_weak function declaration and
do an inline conditional branch at the deletion call site. This doesn't
work because extern_weak only works on MachO if you have some archive
providing the default value of the extern_weak symbol. Arranging to
provide such an archive has the same challenges as providing the symbol
in the standard library. Not to mention that extern_weak doesn't really
work on COFF.
Reviewers: rsmith, rjmccall
Differential Revision: http://reviews.llvm.org/D8467
llvm-svn: 232788
There will be an explicit template instantiation in another translation
unit which will provide the definition of the VF/VB-Tables.
This fixes PR22932.
llvm-svn: 232680
Codegen for threadprivate variables (and in some other cases) may cause crash of the compiler if some diagnostic is produced later. This happens because some of the autogenerated globals are not removed from InternalVars StringMap when llvm::Module is reset.
Differential Revision: http://reviews.llvm.org/D8360
llvm-svn: 232610
The HandlerMap describes, to the runtime, what sort of catches surround
the try. In principle, this structure has to be emitted by the backend
because only it knows the layout of the stack (the runtime needs to know
where on the stack the destination of a copy lives, etc.) but there is
some C++ specific information that the backend can't reason about.
Stick this information in special LLVM globals with the relevant
"const", "volatile", "reference" info mangled into the name.
llvm-svn: 232538
Qualifiers are located next to the TypeDescriptor in order to properly
ensure that a pointer type can only be caught by a more qualified catch
handler. This means that a catch handler of type 'const int *' requires
an RTTI object for 'int *'. We got this correct for 'throw' but not for
'catch'.
N.B. We don't currently have the means to store the qualifiers because
LLVM's EH strategy is tailored to the Itanium scheme. The Itanium ABI
stores qualifiers inside the type descriptor in such a way that the
manner of qualification is stored in addition to the pointee type's
descriptor. Perhaps the best way of modeling this for the MS ABI is
using an aggregate type to bundle the qualifiers with the descriptor?
This is tricky because we want to make it clear to the optimization
passes which catch handlers invalidate other handlers.
My current thoughts on a design for this is along the lines of:
{ { TypeDescriptor* TD, i32 QualifierFlags }, i32 MiscFlags }
The idea is that the inner most aggregate is all that is needed to
communicate that one catch handler might supercede another. The
'MiscFlags' field would be used to hold the bitpattern for the notion
that the 'catch' handler does not need to invoke a copy-constructor
because we are catching by reference.
llvm-svn: 232318
Classes can be defined in multiple translation units. This means that
the static constexpr data members should have identical initializers in
all translation units. Implement this by giving the reference temporary
linkonce_odr linkage.
llvm-svn: 229900
Summary:
This is especially important for targets that use multiple address spaces,
and commonly place global variables in address spaces other than zero.
Fixes PR22383
Test Plan: New test case added: llvm-used.cu
Reviewers: jingyue
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D7345
llvm-svn: 227861
Currently we emit DeferredDeclsToEmit in reverse order. This patch changes that.
The advantages of the change are that
* The output order is a bit closer to the source order. The change to
test/CodeGenCXX/pod-member-memcpys.cpp is a good example.
* If we decide to deffer more, it will not cause as large changes in the
estcases as it would without this patch.
llvm-svn: 226751
This produces comdats for vtables, typeinfo, typeinfo names, and vtts.
When combined with llvm not producing implicit comdats, not doing this would
cause code bloat on ELF and link errors on COFF.
llvm-svn: 226227
Sorry for the noise, I managed to miss a bunch of recent regressions of
include orderings here. This should actually sort all the includes for
Clang. Again, no functionality changed, this is just a mechanical
cleanup that I try to run periodically to keep the #include lines as
regular as possible across the project.
llvm-svn: 225979
The llvm IR until recently had no support for comdats. This was a problem when
targeting C++ on ELF/COFF as just using weak linkage would cause quite a bit of
dead bits to remain on the executable (unless -ffunction-sections,
-fdata-sections and --gc-sections were used).
To fix the problem, llvm's codegen will just assume that any weak or linkonce
that is not in an explicit comdat should be output in one with the same name as
the global.
This unfortunately breaks cases like pr19848 where a weak symbol is not
xpected to be part of any comdat.
Now that we have explicit comdats in the IR, we can finally get both cases
right.
This first patch just makes clang give explicit comdats to GlobalValues where
t is allowed to.
A followup patch to llvm will then stop implicitly producing comdats.
llvm-svn: 225705
Their linkage can change if they are later explicitly instantiated. We would
previously emit such functions eagerly (as opposed to lazily on first use) if
they have a 'dllexport' or 'used' attribute, and fail an assert when hitting the
explicit instantiation.
This is achieved by replacing the old CodeGenModule::MayDeferGeneration() method
with two new ones: MustBeEmitted() and MayBeEmittedEagerly().
Differential Revision: http://reviews.llvm.org/D6674
llvm-svn: 225570
having OptimizeNone remove them again, just don't add them in the
first place if the function already has OptimizeNone.
Note that MinSize can still appear due to attributes on different
declarations; a future patch will address that.
llvm-svn: 224047
The logic for lowering profiling counters has been moved to an LLVM
pass. Emit the intrinsics rather than duplicating the whole pass in
clang.
llvm-svn: 223683
ARM ABI specifies that all the libcalls use soft FP ABI
(even hard FP binaries). These days clang emits _mulsc3 / _muldc3
calls with default (C) calling convention which would be translated
into AAPCS_VFP LLVM calling and thus the result of complex
multiplication will be bogus.
Introduce a way for a target to specify explicitly calling
convention for libcalls. Right now this is temporary correctness
fix. Ultimately, we'll end with intrinsic for complex
multiplication and all calling convention decisions for libcalls
will be put into backend.
llvm-svn: 223123
Richard rejected my Sema change to interpret an integer literal zero in
a varargs context as a null pointer, so -Wsentinel sees an integer
literal zero and fires off a warning. Only CodeGen currently knows that
it promotes integer literal zeroes in this context to pointer size on
Windows. I didn't want to teach -Wsentinel about that compatibility
hack. Therefore, I'm migrating to C++11 nullptr.
llvm-svn: 223079
Summary:
This distinguishes between -fpic and -fPIC now, with the additions in LLVM for
PIC level support.
Test Plan: No regressions
Reviewers: echristo, rafael
Reviewed By: rafael
Subscribers: rnk, emaste, llvm-commits
Differential Revision: http://reviews.llvm.org/D5400
llvm-svn: 222227
For all threadprivate variables which have constructor/destructor emit call to void __kmpc_threadprivate_register(ident_t * <Current Location>, void *<Original Global Addr>, kmpc_ctor <Constructor>, kmpc_cctor NULL, kmpc_dtor <Destructor>);
In expressions all references to such variables are replaced by calls to void *__kmpc_threadprivate_cached(ident_t *<Current Location>, kmp_int32 <Current Thread Id>, void *<Original Global Addr>, size_t <Size of Data>, void ***<Pointer to autogenerated cache – array of private copies of threadprivate variable>);
Test test/OpenMP/threadprivate_codegen.cpp checks that codegen is correct. Also it checks that codegen is correct after serialization/deserialization and one of passes verifies debug info.
Differential Revision: http://reviews.llvm.org/D4002
llvm-svn: 221663
Use the bitmask to store the set of enabled sanitizers instead of a
bitfield. On the negative side, it makes syntax for querying the
set of enabled sanitizers a bit more clunky. On the positive side, we
will be able to use SanitizerKind to eventually implement the
new semantics for -fsanitize-recover= flag, that would allow us
to make some sanitizers recoverable, and some non-recoverable.
No functionality change.
llvm-svn: 221558
