This fixes building Qt as shared libraries with clang in MinGW
mode; previously subclasses of the QObjectData class (in other
DLLs than the base DLL) failed to find the typeinfo symbols
(that neither were emitted in the base DLL nor in the DLL
containing the subclass).
If the virtual destructor in the newly added testcase wouldn't
be pure (or if there'd be another non-pure virtual method),
it'd be a key function and things would work out even before this
change. Make sure to locally emit the typeinfo for these classes
as well.
This matches what GCC does in this specific testcase.
This fixes the root issue that spawned PR35146. (The difference
to GCC that is initially described in that bug still is present
though.)
Differential Revision: https://reviews.llvm.org/D42641
llvm-svn: 324059
As discussed in the mail thread <https://groups.google.com/a/isocpp.org/forum/
#!topic/std-discussion/T64_dW3WKUk> "Calling noexcept function throug non-
noexcept pointer is undefined behavior?", such a call should not be UB.
However, Clang currently warns about it.
This change removes exception specifications from the function types recorded
for -fsanitize=function, both in the functions themselves and at the call sites.
That means that calling a non-noexcept function through a noexcept pointer will
also not be flagged as UB. In the review of this change, that was deemed
acceptable, at least for now. (See the "TODO" in compiler-rt
test/ubsan/TestCases/TypeCheck/Function/function.cpp.)
To remove exception specifications from types, the existing internal
ASTContext::getFunctionTypeWithExceptionSpec was made public, and some places
otherwise unrelated to this change have been adapted to call it, too.
This is the cfe part of a patch covering both cfe and compiler-rt.
Differential Revision: https://reviews.llvm.org/D40720
llvm-svn: 321859
Summary:
The C++ Itanium ABI says:
No cookie is required if the new operator being used is ::operator new[](size_t, void*).
We should only avoid poisoning the cookie if we're calling this
operator, not others. This is dealt with before the call to
InitializeArrayCookie.
Reviewers: rjmccall, kcc, rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D41301
llvm-svn: 321645
Under the Microsoft ABI, it is possible for an object not to have
a virtual table pointer of its own if all of its virtual functions
were introduced by virtual bases. In that case, we need to load the
vtable pointer from one of the virtual bases and perform the type
check using its type.
Differential Revision: https://reviews.llvm.org/D41036
llvm-svn: 320638
Summary:
The MS ABI convention is that the 'this' pointer on entry is the address
of the vfptr that was used to make the virtual method call. In other
words, the pointer on entry always points to the base subobject that
introduced the virtual method. Consider this hierarchy:
struct A { virtual void f() = 0; };
struct B { virtual void g() = 0; };
struct C : A, B {
void f() override;
void g() override;
};
On entry to C::g, [ER]CX will contain the address of C's B subobject,
and C::g will have to subtract sizeof(A) to recover a pointer to C.
Before this change, we applied this adjustment in the prologue and
stored the new value into the "this" local variable alloca used for
debug info. However, MSVC does not do this, presumably because it is
often profitable to fold the adjustment into later field accesses. This
creates a problem, because the debugger expects the variable to be
unadjusted. Unfortunately, CodeView doesn't have anything like DWARF
expressions for computing variables that aren't in the program anymore,
so we have to declare 'this' to be the unadjusted value if we want the
debugger to see the right value.
This has the side benefit that, in optimized builds, the 'this' pointer
will usually be available on function entry because it doesn't require
any adjustment.
Reviewers: hans
Subscribers: aprantl, cfe-commits
Differential Revision: https://reviews.llvm.org/D40109
llvm-svn: 318440
llvm-objcopy is getting to where it can be used in non-trivial ways
(such as for dwarf fission in clang). It now supports dwarf fission but
this feature hasn't been thoroughly tested yet. This change allows
people to optionally build clang to use llvm-objcopy rather than GNU
objcopy. By default GNU objcopy is still used so nothing should change.
Differential Revision: https://reviews.llvm.org/D39029
llvm-svn: 317960
This feature is not (yet) approved by the C++ committee, so this is liable to
be reverted or significantly modified based on committee feedback.
No functionality change intended for existing code (a new type must be defined
in namespace std to take advantage of this feature).
llvm-svn: 315662
This is a recommit of r312781; in some build configurations
variable names are omitted, so changed the new regression
test accordingly.
llvm-svn: 312794
This adds _Float16 as a source language type, which is a 16-bit floating point
type defined in C11 extension ISO/IEC TS 18661-3.
In follow up patches documentation and more tests will be added.
Differential Revision: https://reviews.llvm.org/D33719
llvm-svn: 312781
This fixes cases where dynamic classes produced RTTI data with
external linkage, producing linker errors about duplicate symbols.
This touches code close to what was changed in SVN r244266, but
this change doesn't break the tests added in that revision.
The previous version had missed to update CodeGenCXX/virt-dtor-key.cpp,
which had a behaviour change only when running the testsuite on windows.
Differential revision: https://reviews.llvm.org/D37327
llvm-svn: 312306
This fixes cases where dynamic classes produced RTTI data with
external linkage, producing linker errors about duplicate symbols.
This touches code close to what was changed in SVN r244266, but
this change doesn't break the tests added in that revision.
Differential revision: https://reviews.llvm.org/D37206
llvm-svn: 312224
This patch adds a flag -fclang-abi-compat that can be used to request that
Clang attempts to be ABI-compatible with some older version of itself.
This is provided on a best-effort basis; right now, this can be used to undo
the ABI change in r310401, reverting Clang to its prior C++ ABI for pass/return
by value of class types affected by that change, and to undo the ABI change in
r262688, reverting Clang to using integer registers rather than SSE registers
for passing <1 x long long> vectors. The intent is that we will maintain this
backwards compatibility path as we make ABI-breaking fixes in future.
The reversion to the old behavior for r310401 is also applied to the PS4 target
since that change is not part of its platform ABI (which is essentially to do
whatever Clang 3.2 did).
llvm-svn: 311823
constructors when deciding whether classes should be passed indirectly.
This fixes ABI differences between Clang and GCC:
* Previously, Clang ignored the move constructor when making this
determination. It now takes the move constructor into account, per
https://github.com/itanium-cxx-abi/cxx-abi/pull/17 (this change may
seem recent, but the ABI change was agreed on the Itanium C++ ABI
list a long time ago).
* Previously, Clang's behavior when the copy constructor was deleted
was unstable -- depending on whether the lazy declaration of the
copy constructor had been triggered, you might get different behavior.
We now eagerly declare the copy constructor whenever its deletedness
is unclear, and ignore deleted copy/move constructors when looking for
a trivial such constructor.
This also fixes an ABI difference between Clang and MSVC:
* If the copy constructor would be implicitly deleted (but has not been
lazily declared yet), for instance because the class has an rvalue
reference member, we would pass it directly. We now pass such a class
indirectly, matching MSVC.
Based on a patch by Vassil Vassilev, which was based on a patch by Bernd
Schmidt, which was based on a patch by Reid Kleckner!
This is a re-commit of r310401, which was reverted in r310464 due to ARM
failures (which should now be fixed).
llvm-svn: 310983
constructors when deciding whether classes should be passed indirectly.
This fixes ABI differences between Clang and GCC:
* Previously, Clang ignored the move constructor when making this
determination. It now takes the move constructor into account, per
https://github.com/itanium-cxx-abi/cxx-abi/pull/17 (this change may
seem recent, but the ABI change was agreed on the Itanium C++ ABI
list a long time ago).
* Previously, Clang's behavior when the copy constructor was deleted
was unstable -- depending on whether the lazy declaration of the
copy constructor had been triggered, you might get different behavior.
We now eagerly declare the copy constructor whenever its deletedness
is unclear, and ignore deleted copy/move constructors when looking for
a trivial such constructor.
This also fixes an ABI difference between Clang and MSVC:
* If the copy constructor would be implicitly deleted (but has not been
lazily declared yet), for instance because the class has an rvalue
reference member, we would pass it directly. We now pass such a class
indirectly, matching MSVC.
llvm-svn: 310401
r303175 made changes to have __cxa_allocate_exception return a 16-byte
aligned pointer, so it's no longer necessary to specify a lower
alignment (8-bytes) for exception objects on Darwin.
rdar://problem/32363695
llvm-svn: 309308
The initializer for a static local variable cannot be hot, because it runs at
most once per program. That's not quite the same thing as having a low branch
probability, but under the assumption that the function is invoked many times,
modeling this as a branch probability seems reasonable.
For TLS variables, the situation is less clear, since the initialization side
of the branch can run multiple times in a program execution, but we still
expect initialization to be rare relative to non-initialization uses. It would
seem worthwhile to add a PGO counter along this path to make this estimation
more accurate in future.
For globals with guarded initialization, we don't yet apply any branch weights.
Due to our use of COMDATs, the guard will be reached exactly once per DSO, but
we have no idea how many DSOs will define the variable.
llvm-svn: 309195
Under Windows Itanium, we need to export virtual and non-virtual thunks
if the functions being thunked are exported. These thunks would
previously inherit their dllexport attribute from the declaration, but
r298330 changed declarations to not have dllexport attributes. We
therefore need to add the dllexport attribute to the definition
ourselves now. This is consistent with MinGW GCC's behavior.
This redoes r306770 but limits the logic to Itanium. MicrosoftCXXABI's
setThunkLinkage ensures that thunks aren't exported under that ABI, so
I'm handling this in ItaniumCXXABI's setThunkLinkage for symmetry.
We need to export these thunks because they can be referenced outside
the library they're defined in. For example, if a child class without a
key function inherits from a parent class with a key function, the
parent's thunks will only be defined in the library with the key
function, but the construction vtable for the parent in the child might
be emitted outside the library (since the child doesn't have a key
function), and it needs to reference the parent's thunks.
We don't need to mark these thunks as imported since any references to
them will occur in data, so the compiler can't generate the IAT load
sequence anyway. Instead, we rely on the linker generating import thunks
for the thunks.
Differential Revision: https://reviews.llvm.org/D34972
llvm-svn: 308899
In addition to the formal linkage rules, the Modules TS includes cases where
internal-linkage symbols within a module interface unit can be referenced from
outside the module via exported inline functions / templates. We give such
declarations "module-internal linkage", which is formally internal linkage, but
results in an externally-visible symbol.
llvm-svn: 307434
Summary:
If the first parameter of the function is the ImplicitParamDecl, codegen
automatically marks it as an implicit argument with `this` or `self`
pointer. Added internal kind of the ImplicitParamDecl to separate
'this', 'self', 'vtt' and other implicit parameters from other kind of
parameters.
Reviewers: rjmccall, aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D33735
llvm-svn: 305075
Summary:
We can emit vtable definition having inline function
if they are all emitted.
Reviewers: rjmccall, rsmith
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D33437
llvm-svn: 304394
Use variadic templates instead of relying on <cstdarg> + sentinel.
This enforces better type checking and makes code more readable.
Differential revision: https://reviews.llvm.org/D32550
llvm-svn: 302572
Meta: The ultimate goal is to teach ExtParameterInfo about
pass_object_size attributes. This is necessary for that, since our
ExtParameterInfo is a bit buggy in C++. I plan to actually make use of
this Prefix/Suffix info in the near future, but I like small
single-purpose changes. Especially when those changes are hard to
actually test...
At the moment, some of our C++-specific CodeGen pretends that ABIs can
only add arguments to the beginning of a function call. This isn't quite
correct: args can be appended to the end, as well. It hasn't mattered
much until now, since we seem to only use this "number of arguments
added" data when calculating the ExtParameterInfo to use when making a
CGFunctionInfo. Said ExtParameterInfo is currently only used for
ParameterABIs (Swift) and ns_consumed (ObjC).
So, this patch allows ABIs to indicate whether args they added were at
the beginning or end of an argument list. We can use this information to
emit ExtParameterInfos more correctly, though like said, that bit is
coming soon.
No tests since this is theoretically a nop.
llvm-svn: 295870
Removed ndrange_t as Clang builtin type and added
as a struct type in the OpenCL header.
Use type name to do the Sema checking in enqueue_kernel
and modify IR generation accordingly.
Review: D28058
Patch by Dmitry Borisenkov!
llvm-svn: 295311
This change adds a new type node, DeducedTemplateSpecializationType, to
represent a type template name that has been used as a type. This is modeled
around AutoType, and shares a common base class for representing a deduced
placeholder type.
We allow deduced class template types in a few more places than the standard
does: in conditions and for-range-declarators, and in new-type-ids. This is
consistent with GCC and with discussion on the core reflector. This patch
does not yet support deduced class template types being named in typename
specifiers.
llvm-svn: 293207
* Do not initialize these variables when initializing the rest of the
thread_locals in the TU; they have unordered initialization so they can be
initialized by themselves.
This fixes a rejects-valid bug: we would make the per-variable initializer
function internal, but put it in a comdat keyed off the variable, resulting
in link errors when the comdat is selected from a different TU (as the per
TU TLS init function tries to call an init function that does not exist).
* On Darwin, when we decide that we're not going to emit a thread wrapper
function at all, demote its linkage to External. Fixes a verifier failure
on explicit instantiation of a thread_local variable on Darwin.
llvm-svn: 291865
Properly attribute DLL storage to runtime functions. When generating the
runtime function, scan for an existing declaration which may provide an explicit
declaration (local storage) or a DLL import or export storage from the user.
Honour that if available. Otherwise, if building with a local visibility of the
public or standard namespaces (-flto-visibility-public-std), give the symbols
local storage (it indicates a /MT[d] link, so static runtime). Otherwise,
assume that the link is dynamic, and give the runtime function dllimport
storage.
This allows for implementations to get the correct storage as long as they are
properly declared, the user to override the import storage, and in case no
explicit storage is given, use of the import storage.
llvm-svn: 289776
This annotation allows the optimizer to split vtable groups, as permitted by
a change to the Itanium ABI [1] that prevents compilers from adjusting virtual
table pointers between virtual tables.
[1] https://github.com/MentorEmbedded/cxx-abi/pull/7
Differential Revision: https://reviews.llvm.org/D24431
llvm-svn: 289585
In a future change, this representation will allow us to use the new inrange
annotation on getelementptr to allow the optimizer to split vtable groups.
Differential Revision: https://reviews.llvm.org/D22296
llvm-svn: 289584
When emitting RTTI for EH only, we would mark the locally defined (LinkOnceODR)
RTTI definition as dllimport, which is incorrect. Ensure that if we are
generating the type information for EH only, it is marked as LinkOnceODR and we
do not make it dllimport.
llvm-svn: 288721
When a C++ record is marked with dllexport mark both the typeinfo and the
typeinfo name as being exported. Handle dllimport as the inverse. This applies
to the itanium environment and not the MinGW environment.
llvm-svn: 288546
on cxx-abi-dev (thread starting 2016-10-11). This is currently hidden behind a
cc1-only -m flag, pending discussion of how best to deal with language changes
that require use of new symbols from the ABI library.
llvm-svn: 285664
Summary:
This patch was introduced one year ago, but because my google account
was disabled, I didn't get email with failing buildbot and I missed
revert of this commit. There was small but in test regex.
I am back.
Reviewers: rsmith, rengolin
Subscribers: nlewycky, rjmccall, cfe-commits
Differential Revision: https://reviews.llvm.org/D26117
llvm-svn: 285497
abstract information about the callee. NFC.
The goal here is to make it easier to recognize indirect calls and
trigger additional logic in certain cases. That logic will come in
a later patch; in the meantime, I felt that this was a significant
improvement to the code.
llvm-svn: 285258
Martin Storsjo