This patch implements __unaligned as a type qualifier; before that, it was
modeled as an attribute. Proper mangling of __unaligned is implemented as well.
Some OpenCL code/tests are tangenially affected, as they relied on existing
number and sizes of type qualifiers.
Differential Revision: http://reviews.llvm.org/D18596
llvm-svn: 266415
This patch corresponds to review:
http://reviews.llvm.org/D15120
It adds support for the __float128 keyword, literals and a target feature to
enable it. This support is disabled by default on all targets and any target
that has support for this type is free to add it.
Based on feedback that I've received from target maintainers, this appears to
be the right thing for most targets. I have not heard from the maintainers of
X86 which I believe supports this type. I will subsequently investigate the
impact of enabling this on X86.
llvm-svn: 266186
CodeGen-level implementation. Instead of adding an attribute to clang's
FunctionDecl, add the IR attribute directly. This means a module built with
this flag is now compatible with code built without it and vice versa.
This change also results in the 'noalias' attribute no longer being added to
calls to operator new in the IR; it's now only added to the declaration. It
also fixes a bug where we failed to add the attribute to the 'nothrow' versions
(because we didn't implicitly declare them, there was no good time to inject a
fake attribute).
llvm-svn: 265728
landing pads.
Previously, lifetime.end intrinsics were inserted only on normal control
flows. This prevented StackColoring from merging stack slots for objects
that were destroyed on the exception handling control flow since it
couldn't tell their lifetime ranges were disjoint. This patch fixes
code-gen to emit the intrinsic on both control flows.
rdar://problem/22181976
Differential Revision: http://reviews.llvm.org/D18196
llvm-svn: 265197
alignment on Darwin.
Itanium C++ ABI specifies that _Unwind_Exception should be double-word
aligned (16B). To conform to the ABI, libraries implementing exception
handling declare the struct with __attribute__((aligned)), which aligns
the unwindHeader field (and the end of __cxa_exception) to the default
target alignment (which is typically 16-bytes).
struct __cxa_exception {
...
// struct is declared with __attribute__((aligned)).
_Unwind_Exception unwindHeader;
};
Based on the assumption that _Unwind_Exception is declared with
__attribute__((aligned)), ItaniumCXXABI::getAlignmentOfExnObject returns
the target default alignment for __attribute__((aligned)). It turns out
that libc++abi, which is used on Darwin, doesn't declare the struct with
the attribute and therefore doesn't guarantee that unwindHeader is
aligned to the alignment specified by the ABI, which in some cases
causes the program to crash because of unaligned memory accesses.
This commit avoids crashes due to unaligned memory accesses by having
getAlignmentOfExnObject return an 8-byte alignment on Darwin. I've only
fixed the problem for Darwin, but we should also figure out whether other
platforms using libc++abi need similar fixes.
rdar://problem/25314277
Differential revision: http://reviews.llvm.org/D18479
llvm-svn: 264998
...as that is apparently what MSVC does. This is an updated version of r263738,
which had to be reverted in r263740 due to test failures. The original version
had erroneously emitted functions that are defined in class templates, too (see
the updated "Handle friend functions" code in EmitDeferredDecls,
lib/CodeGen/ModuleBuilder.cpp). (The updated tests needed to be split out into
their own dllexport-ms-friend.cpp because of the CHECK-NOTs which would have
interfered with subsequent CHECK-DAGs in dllexport.cpp.)
Differential Revision: http://reviews.llvm.org/D18430
llvm-svn: 264841
The _GUID_ descriptors emitted by MSVC have alignment 8 for 64-bit
builds: we should do the same if the linker picks the "wrong" COMDAT.
llvm-svn: 264530
In r259975 we rauw'ed the scope of enum declarations without taking into
account that DIBuilder strips out scope references that point to the
DICompileUnit to facilitate type uniquing.
This testcase guards against making the same mistake again.
<rdar://problem/25078246>
llvm-svn: 264366
While we correctly assigned an inheritance model for the source of a
member pointer upcast, we did not do so for the destination.
This fixes PR27030.
llvm-svn: 264065
Implement lambda capture of *this by copy.
For e.g.:
struct A {
int d = 10;
auto foo() { return [*this] (auto a) mutable { d+=a; return d; }; }
};
auto L = A{}.foo(); // A{}'s lifetime is gone.
// Below is still ok, because *this was captured by value.
assert(L(10) == 20);
assert(L(100) == 120);
If the capture was implicit, or [this] (i.e. *this was captured by reference), this code would be otherwise undefined.
Implementation Strategy:
- amend the parser to accept *this in the lambda introducer
- add a new king of capture LCK_StarThis
- teach Sema::CheckCXXThisCapture to handle by copy captures of the
enclosing object (i.e. *this)
- when CheckCXXThisCapture does capture by copy, the corresponding
initializer expression for the closure's data member
direct-initializes it thus making a copy of '*this'.
- in codegen, when assigning to CXXThisValue, if *this was captured by
copy, make sure it points to the corresponding field member, and
not, unlike when captured by reference, what the field member points
to.
- mark feature as implemented in svn
Much gratitude to Richard Smith for his carefully illuminating reviews!
llvm-svn: 263921
This makes sure we don't generate a lot of code to spill/reload
CSRs when calling tls_init from the access functions.
This helps performance when tls_init is not inlined into the access
functions.
llvm-svn: 263854
Summary: ...as that is apparently what MSVC does
Reviewers: rnk
Patch by Stephan Bergmann
Differential Revision: http://reviews.llvm.org/D15267
llvm-svn: 263738
The relative vtable ABI will use a struct rather than an array as the type
of a vtable. LLVM only allows 32-bit integers as struct indices, so we need
to use 32-bit integers to get addresses of address points. In order to keep
the code simple, we might as well do that unconditionally.
It's probably a reasonable implementation limit to support no more than 2
billion virtual functions per class.
This change causes quite a bit of churn in the test suite, so I'm making
it separately.
Differential Revision: http://reviews.llvm.org/D18113
llvm-svn: 263469
This marks virtual function declarations, as well as runtime library functions
__cxa_pure_virtual, __cxa_deleted_virtual and _purecall, as unnamed_addr. This
will allow us to correctly form relative references to them from vtables in
the relative vtable ABI.
Differential Revision: http://reviews.llvm.org/D18071
llvm-svn: 263464
Summary:
This flag is enabled by default in the driver when NDEBUG is set. It
is forwarded on the LLVMContext to discard all value names (but
GlobalValue) for performance purpose.
This an improved version of D18024
Reviewers: echristo, chandlerc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D18127
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 263394
Really long symbols are hashed using MD5 and prefixed/suffixed with the
usual sigils. There is an additional reason beyond the usual
compatibility with MSVC, it is important to keep COFF symbols shorter
than 0xFFFF because the CodeView debugging format has a maximum
symbol/record size of 0xFFFF.
There are some quirks worth noting:
- Some mangled names reference other entities which are mangled
separately. A quick example:
int I;
template <int *> struct S {};
S<I> s;
In this case, the mangling for 's' doesn't depend directly on the
mangling for 'I'. While 's' would need an MD5 hash if 'I' also needed
one, the hash for 's' applied to the fully realized mangled name. In
other words, the mangled name for 's' will not depend on the MD5 of the
mangled name for 'I'.
- Some mangled names, like the venerable CatchableType, embed the MD5
verbatim.
- Finally, the complete object locator is handled as a special case.
A complete object locators are mangled exactly like a VFTable except for
a small deviation in the prefix sigils. However, complete object
locators for hashed vftables result in a complete object locator whose
name is identical to the vftable except for an additional suffix.
llvm-svn: 262818
Summary:
This change just adds tests for some corner cases of dllimport/dllexport,
primarily for some static methods.
We plan to enable dllimport/dllexport support for the PS4, and these
additional tests are for points we previously were testing internally.
-Warren Ristow
SN Systems - Sony Computer Entertainment Group
Reviewers: rnk
Subscribers: silvas
Differential Revision: http://reviews.llvm.org/D17775
llvm-svn: 262442
ARC ownership-convention function type modifications.
According to the Itanium ABI, vendor extended qualifiers are
supposed to be mangled in reverse-alphabetical order before
any CVR qualifiers. The ARC function type conventions are
plausibly order-significant (they are associated with the
function type), which permits us to ignore the need to correctly
inter-order them with any other vendor qualifiers on the parameter
and return types.
Implementing these rules correctly is technically an ABI break.
Apple is comfortable with the risk of incompatibility here for
the ARC features, and I believe that address-space qualification
is still uncommon enough to allow us to adopt the conforming
rule without serious risk. Still, targets which make heavy
use of address space qualification may want to revert to the
non-conforming order.
llvm-svn: 262414
Functions with an explicit exception specification have their behavior
dictated by the specification. The additional /EHc behavior only comes
into play if no exception specification is given.
llvm-svn: 262198
Relands r260194 with a fix. If we have a template that transitions from
an extern template to an explicitly instantiated dllexport template, we
would add that class to the delayed exported class list without flushing
it.
For explicit instantiations, we can just flush the list of delayed
classes immediately. We don't have to worry about the bug fixed in
r260194 in this case because explicit instantiations can only occur at
file and namespace scope.
Fixes PR26490.
llvm-svn: 262056
This patch introduces the -fwhole-program-vtables flag, which enables the
whole-program vtable optimization feature (D16795) in Clang.
Differential Revision: http://reviews.llvm.org/D16821
llvm-svn: 261767
We gave a VBTable dllimport storage class and external linkage while
also providing an initializer. An initializer is only valid if the
VBTable has available_externally linkage. Fix this by setting the
linkage to available_externally in situ while generating the
initializer.
This fixes PR26686.
llvm-svn: 261535
This reverts commit r260449.
We would supress our emission of vftable definitions if we thought
another translation unit would provide the definition because we saw an
explicit instantiation declaration. This is not the case with
dllimport, we want to synthesize a definition of the vftable regardless.
This fixes PR26569.
llvm-svn: 260548
Referencing a dllimported vtable is impossible in a constexpr
constructor. It would be friendlier to C++ programmers if we
synthesized a copy of the vftable which referenced imported virtual
functions. This would let us initialize the object in a way which
preserves both the intent to import functionality from another DLL while
also making constexpr work.
Differential Revision: http://reviews.llvm.org/D17061
llvm-svn: 260388
Summary: This isn't a FileCheck directive; it does nothing.
Reviewers: jroelofs
Subscribers: cfe-commits, majnemer
Differential Revision: http://reviews.llvm.org/D17051
llvm-svn: 260334
A dllimport'd vtable always points one past the RTTI data, this means
that the initializer will never end up referencing the data. Our
emission is a harmless waste.
llvm-svn: 260062
It is possible for enums to be created as part of their own
declcontext. We need to cache a placeholder to avoid the type being
created twice before hitting the cache.
<rdar://problem/24493203>
llvm-svn: 259975
Because the Decl is explicitly passed as nullptr further up the call chain, it
is possible to invoke isa on a nullptr, which will assert. Guard against the
nullptr.
Take the opportunity to reuse the helper method rather than re-implementing this
logic.
llvm-svn: 259874
Avoid crashing when printing diagnostics for vtable-related CFI
errors. In diagnostic mode, the frontend does an additional check of
the vtable pointer against the set of all known vtable addresses and
lets the runtime handler know if it is safe to inspect the vtable.
http://reviews.llvm.org/D16823
llvm-svn: 259716
C++ ABI library for the same set of types for which we expect the C++ ABI
library to provide the RTTI.
Specifically:
1) __int128 and unsigned __int128 are now emitted into the ABI library. We
always expected them to be there but never actually made sure to emit them.
2) Do not expect OpenCL builtin types to have type info in the C++ ABI library.
Neither libc++abi nor libstdc++ puts them there when built with either GCC
or Clang.
This matches GCC's behavior.
llvm-svn: 259616
Allow "mode" attribute for enum types, except for vector modes, for compatibility with GCC.
Support "mode" attribute with dependent types.
Differential Revision: http://reviews.llvm.org/D16219
llvm-svn: 259497
Clang's CodeGen has several paths which end up invoking or calling a
function. The one that we used for calls to __RTtypeid did not
appropriately annotate the call with a funclet bundle.
This fixes PR26329.
llvm-svn: 258877
Member pointers in the MS ABI are tricky for a variety of reasons.
The size of a member pointer is indeterminate until the program reaches
a point where the representation is required to be known. However,
*pointers* to member pointers may exist without knowing the pointee
type's representation. In these cases, we synthesize an opaque LLVM
type for the pointee type.
However, we can be in a situation where the underlying member pointer's
representation became known mid-way through the program. To account for
this, we attempted to manicure CodeGen's type-cache so that we can
replace the opaque member pointer type with the real deal while leaving
the pointer types unperturbed. This, unfortunately, is a problematic
approach to take as we will violate CodeGen's invariants.
These violations are mostly harmless but let's do the right thing
instead: invalidate the type-cache if a member pointer's LLVM
representation changes.
This fixes PR26313.
llvm-svn: 258839
__GetExceptionInfo triggered Sema::LazilyCreateBuiltin which tries to
create a non-templated function decl. This is unnecessary and
ill-advised, there is no need for us to create a declaration for such a
builtin.
This fixes PR26298.
llvm-svn: 258762
* Runtime diagnostic data for cfi-icall changed to match the rest of
cfi checks
* Layout of all CFI diagnostic data changed to put Kind at the
beginning. There is no ABI stability promise yet.
* Call cfi_slowpath_diag instead of cfi_slowpath when needed.
* Emit __cfi_check_fail function, which dispatches a CFI check
faliure according to trap/recover settings of the current module.
* A tiny driver change to match the way the new handlers are done in
compiler-rt.
llvm-svn: 258745
Previous it was allowed to capture VLAs/types with arrays of runtime bounds only inside the first lambda/capture statement in stack. Patch allows to capture these typedefs implicitly in chains of lambdas/captured statements.
llvm-svn: 258669
In the Itanium ABI, vtable may be emitted speculatively as an
available_externally global. Such vtable may not be present at the
link time and should not have a corresponding CFI bit set entry.
llvm-svn: 258596
We might get into bad situations where we try to embed the signature of
an inner lambda into an outer lambda which cannot work: the inner lambda
wants to embed the name of the outer lambda!
Instead, omit the return type for lambdas.
This fixes PR26105.
N.B. While we are here, make lambdas nested within functions use an
artificial scope so that they can get demangled.
llvm-svn: 258003
This is part of a new statistics gathering feature for the sanitizers.
See clang/docs/SanitizerStats.rst for further info and docs.
Differential Revision: http://reviews.llvm.org/D16175
llvm-svn: 257971
This attribute may be attached to a function definition and instructs the backend to generate appropriate function entry/exit code so that
it can be used directly as an interrupt handler.
The IRET instruction, instead of the RET instruction, is used to return from interrupt or exception handlers. All registers, except for the EFLAGS register which is restored by the IRET instruction, are preserved by the compiler.
Any interruptible-without-stack-switch code must be compiled with -mno-red-zone since interrupt handlers can and will, because of the hardware design, touch
the red zone.
interrupt handler must be declared with a mandatory pointer argument:
struct interrupt_frame;
__attribute__ ((interrupt))
void f (struct interrupt_frame *frame) {
...
}
and user must properly define the structure the pointer pointing to.
exception handler:
The exception handler is very similar to the interrupt handler with a different mandatory function signature:
#ifdef __x86_64__
typedef unsigned long long int uword_t;
#else
typedef unsigned int uword_t;
#endif
struct interrupt_frame;
__attribute__ ((interrupt))
void f (struct interrupt_frame *frame, uword_t error_code) {
...
}
and compiler pops the error code off stack before the IRET instruction.
The exception handler should only be used for exceptions which push an error code and all other exceptions must use the interrupt handler.
The system will crash if the wrong handler is used.
Differential Revision: http://reviews.llvm.org/D15709
llvm-svn: 257867
This commit is a follow-up to r251734, r251476, and r249735, which fixes
a bug where function attributes were not attached to thread local
wrapper functions.
rdar://problem/20828324
llvm-svn: 257865
Proper diagnostic and resolution of mangled names' conflicts in variables.
When there is a declaration and a definition using the same name but different
types, we emit what is in the definition. When there are two conflicting
definitions, we issue an error.
Differential Revision: http://reviews.llvm.org/D15686
llvm-svn: 257754
In {CG,}ExprConstant.cpp, we weren't treating vector splats properly.
This patch makes us treat splats more properly.
Additionally, this patch adds a new cast kind which allows a bool->int
cast to result in -1 or 0, instead of 1 or 0 (for true and false,
respectively), so we can sanely model OpenCL bool->int casts in the AST.
Differential Revision: http://reviews.llvm.org/D14877
llvm-svn: 257559
Clang got itself into the situation where we mangled the same
constructor twice with two different constructor types. After one of
the constructors were utilized, the tag used for one of the types
changed from class to struct because a class template became complete.
This resulted in one of the constructor types varying from the other
constructor.
Instead, force "base" constructor types to "complete" if the ABI doesn't
have constructor variants. This will ensure that GlobalDecls for both
variants will get the same mangled name.
This fixes PR26029.
llvm-svn: 257205
Given an expression like `(&Foo)();`, we perform overload resolution as
if we are calling `Foo` directly. This causes problems if `Foo` is a
function that can't have its address taken. This patch teaches overload
resolution to ignore functions that can't have their address taken in
such cases.
Differential Revision: http://reviews.llvm.org/D15590
llvm-svn: 257016
Only function template specializations are exempt from being added to
the NameBackReferences. Redundant variable template specializations
should be appropriately substituted.
llvm-svn: 256623
We didn't add the artificial pass_object_size arguments to the
backreference map which bloated the size of manglings which involved
pass_object_size with duplicate types.
This lets us go from:
?qux@PassObjectSize@@YAHQAHW4__pass_object_size1@__clang@@0W4__pass_object_size1@3@@Z
to:
?qux@PassObjectSize@@YAHQAHW4__pass_object_size1@__clang@@01@Z
llvm-svn: 256622
MSVC doesn't implement a mangling for C99's _Complex so we must invent
our own.
For now, treating it like a class type called _Complex in the __clang
namespace.
This means that 'void f(__Complex int))'
will demangle as: 'void f(struct __clang::_Complex<int>)'
llvm-svn: 256583
MSVC doesn't implement a mangling for C11's _Atomic so we must invent
our own.
For now, treating it like a class type called _Atomic in the __clang
namespace.
This means that 'void f(__Atomic(int))'
will demangle as: 'void f(struct __clang::_Atomic<int>)'
llvm-svn: 256557
We used to produce a type which demangled to:
union __clang_vec8_F
That 'F' is the mangling for 'short' but it is present in the mangled
name in an inappropriate place, leading to it not getting demangled.
Instead, create a synthetic class type in a synthetic namespace called
__clang. With this, it now demangles to:
union __clang::__vector<short,8>
llvm-svn: 256556
is complete (with an error produced if not) and a function that merely queries
whether the type is complete. Either way we'll trigger instantiation if
necessary, but only the former will diagnose and recover from missing module
imports.
The intent of this change is to prevent a class of bugs where code would call
RequireCompleteType(..., 0) and then ignore the result. With modules, we must
check the return value and use it to determine whether the definition of the
type is visible.
This also fixes a debug info quality issue: calls to isCompleteType do not
trigger the emission of debug information for a type in limited-debug-info
mode. This allows us to avoid emitting debug information for type definitions
in more cases where we believe it is safe to do so.
llvm-svn: 256049
Clang-side cross-DSO CFI.
* Adds a command line flag -f[no-]sanitize-cfi-cross-dso.
* Links a runtime library when enabled.
* Emits __cfi_slowpath calls is bitset test fails.
* Emits extra hash-based bitsets for external CFI checks.
* Sets a module flag to enable __cfi_check generation during LTO.
This mode does not yet support diagnostics.
llvm-svn: 255694
We'd like to remove support for terminatepad from LLVM. To do this, we
need to move Clang off of it first. The intent behind terminatepad was
to carefully model exception specifications for the MSVC personality.
However, we don't support exception specifications for the MSVC
personality and neither does MSVC. Instead, MSVC supports
all-or-nothing exception specifications. We can model this limited
usage using cleanuppads which call std::terminate.
Differential Revision: http://reviews.llvm.org/D15478
llvm-svn: 255521
For PS4, generate explicit import for anonymous namespaces and mark it by DW_AT_artificial attribute.
Differential Revision: http://reviews.llvm.org/D12624
llvm-svn: 255281
All problems described in http://llvm.org/PR25636 are implemented except for return value of the 'put' property. This patch fixes this problem with the indexed properties
Differential Revision: http://reviews.llvm.org/D15174
llvm-svn: 255218
These additions were meant to go in as a part of r254554; while it's
certainly nice to have new functionality, it's nicer if we have tests to
go with it. :)
llvm-svn: 254632
`pass_object_size` is our way of enabling `__builtin_object_size` to
produce high quality results without requiring inlining to happen
everywhere.
A link to the design doc for this attribute is available at the
Differential review link below.
Differential Revision: http://reviews.llvm.org/D13263
llvm-svn: 254554
MSVC supports 'property' attribute and allows to apply it to the declaration of an empty array in a class or structure definition.
For example:
```
__declspec(property(get=GetX, put=PutX)) int x[];
```
The above statement indicates that x[] can be used with one or more array indices. In this case, i=p->x[a][b] will be turned into i=p->GetX(a, b), and p->x[a][b] = i will be turned into p->PutX(a, b, i);
Differential Revision: http://reviews.llvm.org/D13336
llvm-svn: 254067
This patch changes the generation of CGFunctionInfo to contain
the FunctionProtoType if it is available. This enables the code
generation for call instructions to look into this type for
exception information and therefore generate better quality
IR - it will not create invoke instructions for functions that
are know not to throw.
llvm-svn: 253926
The pointer returned by __RTDynamicCast must be bitcasted. However, it
was not expected that __RTDynamicCast would be invoked, resulting in the
bitcast occuring in a different BasicBlock than the invoke. This caused
a down-stream PHI to get confused about which BasicBlock the incomming
value was from.
This fixes PR25606.
llvm-svn: 253843
In the Microsoft ABI, the vftable is laid out in the order in the
declaration order of the entities defined within it.
Obviously, only virtual methods end up in the vftable but they will be
placed into the table at the same position as the first entity with the
same name.
llvm-svn: 253523
This is a follow on from a similar LLVM commit: r253511.
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
These intrinsics currently have an explicit alignment argument which is
required to be a constant integer. It represents the alignment of the
source and dest, and so must be the minimum of those.
This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments. The alignment
argument itself is removed.
The only code change to clang is hidden in CGBuilder.h which now passes
both dest and source alignment to IRBuilder, instead of taking the minimum of
dest and source alignments.
Reviewed by Hal Finkel.
llvm-svn: 253512
In r253186, I changed the DIBuilder API to now take size and align
for reference types as well. This was done in preparation for upcoming
changes to the Verifier that will validate that sizes match between
DI types and IR values that are declared as having those types.
This updates clang to actually pass the information through.
llvm-svn: 253190
Several of these tests (the two deleted, and the one removal edit) were
relying on the optimizer to collapse things to test some frontend
feature. The tests were really old and features seemed amply covered by
other parts of the test suite, so I just removed them.
If anyone thinks they're valuable enough to keep/fix, we can play around
with that, for sure.
(inspired by r252872)
llvm-svn: 253114
It has been reported that this test currently fails on some Power buildbots due to them adding a "signext" function attribute.
As that's not what we're checking here, slacken off the test a bit.
llvm-svn: 253055
The ``disable_tail_calls`` attribute instructs the backend to not
perform tail call optimization inside the marked function.
For example,
int callee(int);
int foo(int a) __attribute__((disable_tail_calls)) {
return callee(a); // This call is not tail-call optimized.
}
Note that this attribute is different from 'not_tail_called', which
prevents tail-call optimization to the marked function.
rdar://problem/8973573
Differential Revision: http://reviews.llvm.org/D12547
llvm-svn: 252986
The C++ spec (3.6.1.3) says "The function `main` shall not be used within a program". This implies that it cannot recurse, so add the norecurse attribute to help the midend out a bit.
llvm-svn: 252902
This is about how we handle static member of a template. Before this commit,
we use internal linkage for the IR thread-local variable, which is inefficient.
With this commit, we will start to follow Itanium C++ ABI.
rdar://problem/23415206
Reviewed by John McCall.
llvm-svn: 252814
We used to emit the store prior to branch in the entry block. To make it more
efficient, this commit moves it to the init block. We still mark as initialized
before initializing anything else.
llvm-svn: 252777
This comes up when a derived class destructor is equivalent to a base
class destructor defined in the same TU, and we try to alias them.
A COFF weak alias cannot satisfy a normal undefined symbol reference
from another TU. The other TU must also mark the referenced symbol as
weak, and we can't rely on that.
Clang already has a special case here for dllexport, but we failed to
realize that the problem also applies to other non-discardable symbols
such as those from explicit template instantiations.
Fixes PR25477.
llvm-svn: 252659
The attrubite is applicable to functions and variables and changes
the linkage of the subject to internal.
This is the same functionality as C-style "static", but applicable to
class methods; and the same as anonymouns namespaces, but can apply
to individual methods of a class.
Following the proposal in
http://lists.llvm.org/pipermail/cfe-dev/2015-October/045580.html
llvm-svn: 252648
This attribute is used to prevent tail-call optimizations to the marked
function. For example, in the following piece of code, foo1 will not be
tail-call optimized:
int __attribute__((not_tail_called)) foo1(int);
int foo2(int a) {
return foo1(a); // Tail-call optimization is not performed.
}
The attribute has effect only on statically bound calls. It has no
effect on indirect calls. Also, virtual functions and objective-c
methods cannot be marked as 'not_tail_called'.
rdar://problem/22667622
Differential Revision: http://reviews.llvm.org/D12922
llvm-svn: 252369
Certain CXXConstructExpr nodes require zero-initialization before a
constructor is called. We had a bug in the case where the constructor
is called on a virtual base: we zero-initialized the base's vbptr field.
A complementary bug is present in MSVC where no zero-initialization
occurs for the subobject at all.
This fixes PR25370.
llvm-svn: 251783
attributes to internal functions.
This patch fixes CodeGenModule::CreateGlobalInitOrDestructFunction to
use SetInternalFunctionAttributes instead of SetLLVMFunctionAttributes
to attach function attributes to internal functions.
Also, make sure the correct CGFunctionInfo is passed instead of always
passing what arrangeNullaryFunction returns.
rdar://problem/20828324
Differential Revision: http://reviews.llvm.org/D13610
llvm-svn: 251734
This works around PR25162. The MSVC tables make it very difficult to
correctly inline a C++ destructor that contains try / catch. We've
attempted to address PR25162 in LLVM's backend, but it feels pretty
infeasible. MSVC and ICC both appear to avoid inlining such complex
destructors.
Long term, we want to fix this by making the inliner smart enough to
know when it is inlining into a cleanup, so it can inline simple
destructors (~unique_ptr and ~vector) while avoiding destructors
containing try / catch.
llvm-svn: 251576
We believed that internal linkage variables at global scope which are
not variable template specializations did not have to be mangled.
However, static anonymous unions have no identifier and therefore must
be mangled.
This fixes PR18204.
llvm-svn: 250997
The ELF symbol visibilities are:
- internal: Not visibile across DSOs, cannot pass address across DSOs
- hidden: Not visibile across DSOs, can be called indirectly
- default: Usually visible across DSOs, possibly interposable
- protected: Visible across DSOs, not interposable
LLVM only supports the latter 3 visibilities. Internal visibility is in
theory useful, as it allows you to assume that the caller is maintaining
a PIC register for you in %ebx, or in some other pre-arranged location.
As far as LLVM is concerned, this isn't worth the trouble. Using hidden
visibility is always correct, so we can just do that.
Resolves PR9183.
llvm-svn: 250954
Currently debug info for types used in explicit cast only is not emitted. It happened after a patch for better alignment handling. This patch fixes this bug.
Differential Revision: http://reviews.llvm.org/D13582
llvm-svn: 250795
Out-of-line definitions of static data members which have an inline
initializer must get GVA_DiscardableODR linkage instead of
GVA_StrongExternal linkage.
MSVC 2013's behavior is different with respect to this and would cause
link errors if one TU provided a definition while another did not.
MSVC 2015 fixed this bug, making this OK. Note that the 2015 behavior
is always compatible with 2013: it never produces a strong definition.
This essentially reverts r237787.
llvm-svn: 250757
Previously, our logic when taking the address of an overloaded function
would not consider enable_if attributes, so long as all of the enable_if
conditions on a given candidate were true. So, two functions with
identical signatures (one with enable_if attributes, the other without),
would be considered equally good overloads. If we were calling the
function instead of taking its address, then the function with enable_if
attributes would be preferred.
This patch makes us prefer the candidate with enable_if regardless of if
we're calling or taking the address of an overloaded function.
Differential Revision: http://reviews.llvm.org/D13795
llvm-svn: 250486
These test updates almost exclusively around the change in behavior
around enum: enums without a definition are considered incomplete except
when targeting MSVC ABIs. Since these tests are interested in the
'incomplete-enum' behavior, restrict them to %itanium_abi_triple.
llvm-svn: 249660
No ABI for C++ currently makes it possible to implement the standard
100% perfectly. We wrongly hid some of our compatible behavior behind
-fms-compatibility instead of tying it to the compiler ABI.
llvm-svn: 249656
With this change, most 'g' options are rejected by CompilerInvocation.
They remain only as Driver options. The new way to request debug info
from cc1 is with "-debug-info-kind={line-tables-only|limited|standalone}"
and "-dwarf-version={2|3|4}". In the absence of a command-line option
to specify Dwarf version, the Toolchain decides it, rather than placing
Toolchain-specific logic in CompilerInvocation.
Also fix a bug in the Windows compatibility argument parsing
in which the "rightmost argument wins" principle failed.
Differential Revision: http://reviews.llvm.org/D13221
llvm-svn: 249655
The backend restores the stack pointer after recovering from an
exception. This is similar to r245879, but it doesn't try to use the
normal cleanup mechanism, so hopefully it won't cause the same breakage.
llvm-svn: 249640
We don't have a good place to put them. Our previous spot was causing us
to optimize loads from the exception object to undef, because it was
after the catchpad instruction that models the write to the catch
object.
llvm-svn: 249616
Currently codegen crashes trying to emit casting to bool &. It happens because bool type is converted to i1 and later then lvalue for reference is converted to i1*. But when codegen tries to load this lvalue it crashes trying to load value from this i1*.
Differential Revision: http://reviews.llvm.org/D13325
llvm-svn: 249534
Ensure that the vptr store in the most-derived constructor is not behind
an invariant group barrier. Previously, the base-most vptr store would
be the one behind no barrier, and that could result in the creator of
the object thinking it had the base-most vtable.
This bug caused clang call pure virtual functions when called from
constructor body.
http://reviews.llvm.org/D13373
llvm-svn: 249197
This reverts commit r248982 as it was breaking the ARM buildbots and the fix didn't work.
This reverts commit r248984, the fix that didn't work.
llvm-svn: 249005
someone thought all the bits would be value bits in this case.
Also fix the wording of the warning -- it claimed that the width of 'bool' is
8, which is not correct; the width is 1 bit, whereas the size is 8 bits in our
implementation.
llvm-svn: 248435
This doesn't quite get alias template equivalence right yet, but handles the
egregious cases where we would silently give the wrong answers.
llvm-svn: 248431
This avoids building a fake LLVM IR global variable just to ferry an i32
down into LLVM codegen. It also puts a nail in the coffin of using MS
ABI C++ EH with landingpads, since now we'll assert in the lpad code
when flags are present.
llvm-svn: 247843
ptr in dtor.
Summary:
After destruction, invocation of virtual functions prevented
by poisoning vtable pointer.
Reviewers: eugenis, kcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D12712
Fixed testing callback emission order to account for vptr.
Poison vtable in either complete or base dtor, depending on
if virtual bases exist. If virtual bases exist, poison in
complete dtor. Otherwise, poison in base.
Remove commented-out block.
llvm-svn: 247762
It is dangerous to do LTO on code with strict-vtable-pointers, because
one module has invariant.group.barriers, and the other one not.
In the future I want to just strip all invariant.group metadata from
vptrs loads/stores and get rid of invariant.group.barrier calls.
http://reviews.llvm.org/D12580
llvm-svn: 247724
MS compiler ignores calling convention modifiers for structors. This patch makes
clang do the same (for MS ABI). This fixes PR24595 and makes vswriter.h header
(from Windows SDK 8.1) compilable.
Differential Revision: http://reviews.llvm.org/D12402
llvm-svn: 247619
Current implementation may end up emitting an undefined reference for
an "inline __attribute__((always_inline))" function by generating an
"available_externally alwaysinline" IR function for it and then failing to
inline all the calls. This happens when a call to such function is in dead
code. As the inliner is an SCC pass, it does not process dead code.
Libc++ relies on the compiler never emitting such undefined reference.
With this patch, we emit a pair of
1. internal alwaysinline definition (called F.alwaysinline)
2a. A stub F() { musttail call F.alwaysinline }
-- or, depending on the linkage --
2b. A declaration of F.
The frontend ensures that F.inlinefunction is only used for direct
calls, and the stub is used for everything else (taking the address of
the function, really). Declaration (2b) is emitted in the case when
"inline" is meant for inlining only (like __gnu_inline__ and some
other cases).
This approach, among other nice properties, ensures that alwaysinline
functions are always internal, making it impossible for a direct call
to such function to produce an undefined symbol reference.
This patch is based on ideas by Chandler Carruth and Richard Smith.
llvm-svn: 247494
Current implementation may end up emitting an undefined reference for
an "inline __attribute__((always_inline))" function by generating an
"available_externally alwaysinline" IR function for it and then failing to
inline all the calls. This happens when a call to such function is in dead
code. As the inliner is an SCC pass, it does not process dead code.
Libc++ relies on the compiler never emitting such undefined reference.
With this patch, we emit a pair of
1. internal alwaysinline definition (called F.alwaysinline)
2a. A stub F() { musttail call F.alwaysinline }
-- or, depending on the linkage --
2b. A declaration of F.
The frontend ensures that F.inlinefunction is only used for direct
calls, and the stub is used for everything else (taking the address of
the function, really). Declaration (2b) is emitted in the case when
"inline" is meant for inlining only (like __gnu_inline__ and some
other cases).
This approach, among other nice properties, ensures that alwaysinline
functions are always internal, making it impossible for a direct call
to such function to produce an undefined symbol reference.
This patch is based on ideas by Chandler Carruth and Richard Smith.
llvm-svn: 247465
We used to only select an inheritance model if the pointer to member was
nullptr. Instead, select a model regardless of the member pointer's
value.
N.B. This bug was exposed by making member pointers report true for
isIncompleteType but has been latent since the member pointer scheme's
inception.
llvm-svn: 247464
It seems that there is small bug, and we can't generate assume loads
when some virtual functions have internal visibiliy
This reverts commit 982bb7d966947812d216489b3c519c9825cacbf2.
llvm-svn: 247332
Given a reference to a pointer to member whose class's inheritance model
is unspecified, make sure we come up with an inheritance model in
plausible places. One place we were missing involved LValue to RValue
conversion, another involved unary type traits.
llvm-svn: 247248
This flag causes the compiler to emit bit set entries for functions as well
as runtime bitset checks at indirect call sites. Depends on the new function
bitset mechanism.
Differential Revision: http://reviews.llvm.org/D11857
llvm-svn: 247238
Generating call assume(icmp %vtable, %global_vtable) after constructor
call for devirtualization purposes.
For more info go to:
http://lists.llvm.org/pipermail/cfe-dev/2015-July/044227.html
Edit:
Fixed version because of PR24479.
After this patch got reverted because of ScalarEvolution bug (D12719)
Merged after John McCall big patch (Added Address).
http://reviews.llvm.org/D11859
llvm-svn: 247199
We know that a reference can always be dereferenced. However, we don't
always know the number of bytes if the reference's pointee type is
incomplete. This case was correctly handled but we didn't consider the
case where the type is complete but we cannot calculate its size for ABI
specific reasons. In this specific case, a member pointer's size is
available only under certain conditions.
This fixes PR24703.
llvm-svn: 247188
Summary:
If class or struct has not declared a destructor,
no destructor is emitted, and members are not poisoned
after destruction. This case highlights bug in current
implementation of use-after-dtor poisoning (detailed
in https://github.com/google/sanitizers/issues/596).
Reviewers: eugenis, kcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D12616
Only check simplest object for existence of sanitizing callback.
Rename test.
llvm-svn: 247025
Introduce an Address type to bundle a pointer value with an
alignment. Introduce APIs on CGBuilderTy to work with Address
values. Change core APIs on CGF/CGM to traffic in Address where
appropriate. Require alignments to be non-zero. Update a ton
of code to compute and propagate alignment information.
As part of this, I've promoted CGBuiltin's EmitPointerWithAlignment
helper function to CGF and made use of it in a number of places in
the expression emitter.
The end result is that we should now be significantly more correct
when performing operations on objects that are locally known to
be under-aligned. Since alignment is not reliably tracked in the
type system, there are inherent limits to this, but at least we
are no longer confused by standard operations like derived-to-base
conversions and array-to-pointer decay. I've also fixed a large
number of bugs where we were applying the complete-object alignment
to a pointer instead of the non-virtual alignment, although most of
these were hidden by the very conservative approach we took with
member alignment.
Also, because IRGen now reliably asserts on zero alignments, we
should no longer be subject to an absurd but frustrating recurring
bug where an incomplete type would report a zero alignment and then
we'd naively do a alignmentAtOffset on it and emit code using an
alignment equal to the largest power-of-two factor of the offset.
We should also now be emitting much more aggressive alignment
attributes in the presence of over-alignment. In particular,
field access now uses alignmentAtOffset instead of min.
Several times in this patch, I had to change the existing
code-generation pattern in order to more effectively use
the Address APIs. For the most part, this seems to be a strict
improvement, like doing pointer arithmetic with GEPs instead of
ptrtoint. That said, I've tried very hard to not change semantics,
but it is likely that I've failed in a few places, for which I
apologize.
ABIArgInfo now always carries the assumed alignment of indirect and
indirect byval arguments. In order to cut down on what was already
a dauntingly large patch, I changed the code to never set align
attributes in the IR on non-byval indirect arguments. That is,
we still generate code which assumes that indirect arguments have
the given alignment, but we don't express this information to the
backend except where it's semantically required (i.e. on byvals).
This is likely a minor regression for those targets that did provide
this information, but it'll be trivial to add it back in a later
patch.
I partially punted on applying this work to CGBuiltin. Please
do not add more uses of the CreateDefaultAligned{Load,Store}
APIs; they will be going away eventually.
llvm-svn: 246985
This fixes an issue raised in D12412, where we generated invalid IR.
Thanks to Vedant Kumar for coming up with the initial work around.
Differential Revision: http://reviews.llvm.org/D12412
llvm-svn: 246880
Summary:
Dtor sanitization handled amidst other dtor cleanups,
between cleaning bases and fields. Sanitizer call pushed onto
stack of cleanup operations.
Reviewers: eugenis, kcc
Differential Revision: http://reviews.llvm.org/D12022
Refactoring dtor sanitizing emission order.
- Support multiple inheritance by poisoning after
member destructors are invoked, and before base
class destructors are invoked.
- Poison for virtual destructor and virtual bases.
- Repress dtor aliasing when sanitizing in dtor.
- CFE test for dtor aliasing, and repression of aliasing in dtor
code generation.
- Poison members on field-by-field basis, with collective poisoning
of trivial members when possible.
- Check msan flags and existence of fields, before dtor sanitizing,
and when determining if aliasing is allowed.
- Testing sanitizing bit fields.
llvm-svn: 246815
This implements basic support for compiling (though not yet assembling
or linking) for a WebAssembly target. Note that ABI details are not yet
finalized, and may change.
Differential Revision: http://reviews.llvm.org/D12002
llvm-svn: 246814
TagDecls (structs, enums, etc.) may have the same name for linkage
purposes of one another; to disambiguate, we add a number to the mangled
named. However, we didn't do this if the TagDecl has a pseudo-name for
linkage purposes (it was defined alongside a DeclaratorDecl or a
TypeNameDecl).
This fixes PR24651.
llvm-svn: 246659
A class without a name for linkage purposes gets a name along the lines
of <unnamed-type-foo> where foo is either the name of a declarator which
defined it (like a variable or field) or a
typedef-name (like a typedef or alias-declaration).
We handled the declarator case correctly but it would fall down during
template instantiation if the declarator didn't share the tag's type.
We failed to handle the typedef-name case at all.
Instead, keep track of the association between the two and keep it up to
date in the face of template instantiation.
llvm-svn: 246469
Proper diagnostic and resolution of mangled names conflicts between C++ methods
and C functions. This patch implements support for functions/methods only;
support for variables is coming separately.
Differential Revision: http://reviews.llvm.org/D11297
llvm-svn: 246438
This patch does two things:
1) Don't error about dllimport/export on thread-local static local variables.
We put those attributes on static locals in dllimport/export functions
implicitly in case the function gets inlined. Now, for TLS variables this
is a problem because we can't import such variables, but it's a benign
problem becase:
2) Make sure we never inline a dllimport function TLS static locals. In fact,
never inline a dllimport function that references a non-imported function
or variable (because these are not defined in the importing library). This
seems to match MSVC's behaviour.
Differential Revision: http://reviews.llvm.org/D12422
llvm-svn: 246338
There was linker problem, and it turns out that it is not always safe
to refer to vtable. If the vtable is used, then we can refer to it
without any problem, but because we don't know when it will be used or
not, we can only check if vtable is external or it is safe to to emit it
speculativly (when class it doesn't have any inline virtual functions).
It should be fixed in the future.
http://reviews.llvm.org/D12385
llvm-svn: 246214
Nico Weber