Empty structs in C differ from those in C++.
- C++ requires that empty types have size 1; alignment requirements may
increase the size of the struct.
- The C implementation doesn't let empty structs have a size under 4
bytes. Again, alignment requirements may increase the struct's size.
Add a test to stress these differences.
llvm-svn: 218963
This test includes stdint.h (via stdatomic.h), which might include system
headers (and that might not work, depending on the system configuration).
Attempting to fix llvm-clang-lld-x86_64-debian-fast.
llvm-svn: 218960
This test includes stdint.h, which might include system headers (and that might
not work, depending on the system configuration). Attempting to fix
llvm-clang-lld-x86_64-debian-fast.
llvm-svn: 218959
Adds a Clang-specific implementation of C11's stdatomic.h header. On systems,
such as FreeBSD, where a stdatomic.h header is already provided, we defer to
that header instead (using our __has_include_next technology). Otherwise, we
provide an implementation in terms of our __c11_atomic_* intrinsics (that were
created for this purpose).
C11 7.1.4p1 requires function declarations for atomic_thread_fence,
atomic_signal_fence, atomic_flag_test_and_set,
atomic_flag_test_and_set_explicit, and atomic_flag_clear, and requires that
they have external linkage. Accordingly, we provide these declarations, but if
a user elides the shadowing macros and uses them, then they must have a libc
(or similar) that actually provides definitions.
atomic_flag is implemented using _Bool as the underlying type. This is
consistent with the implementation provided by FreeBSD and also GCC 4.9 (at
least when __GCC_ATOMIC_TEST_AND_SET_TRUEVAL == 1).
Patch by Richard Smith (rebased and slightly edited by me -- Richard said I
should drive at this point).
llvm-svn: 218957
When building with modules enabled, we were defining max_align_t as a typedef
for a different anonymous struct type each time it was included, resulting in
an error if <stddef.h> is not covered by a module map and is included more than
once in the same modules-enabled compilation of C11 or C++11 code.
llvm-svn: 218931
for an overriding method if class has at least one
'override' specified on one of its methods.
Reviewed by Doug Gregor. rdar://18295240
(I have already checked in all llvm files with missing 'override'
methods and Bob Wilson has fixed a TableGen of FastISel so
no warnings are expected from build of llvm after this patch.
I have already verified this).
llvm-svn: 218925
Update debug info testcases for an LLVM metadata schema change to fold
metadata constant operands into a single `MDString`.
Part of PR17891.
llvm-svn: 218913
This adds support for the align_value attribute. This attribute is supported by
Intel's compiler (versions 14.0+), and several of my HPC users have requested
support in Clang. It specifies an alignment assumption on the values to which a
pointer points, and is used by numerical libraries to encourage efficient
generation of vector code.
Of course, we already have an aligned attribute that can specify enhanced
alignment for a type, so why is this additional attribute important? The
problem is that if you want to specify that an input array of T is, say,
64-byte aligned, you could try this:
typedef double aligned_double attribute((aligned(64)));
void foo(aligned_double *P) {
double x = P[0]; // This is fine.
double y = P[1]; // What alignment did those doubles have again?
}
the access here to P[1] causes problems. P was specified as a pointer to type
aligned_double, and any object of type aligned_double must be 64-byte aligned.
But if P[0] is 64-byte aligned, then P[1] cannot be, and this access causes
undefined behavior. Getting round this problem requires a lot of awkward
casting and hand-unrolling of loops, all of which is bad.
With the align_value attribute, we can accomplish what we'd like in a well
defined way:
typedef double *aligned_double_ptr attribute((align_value(64)));
void foo(aligned_double_ptr P) {
double x = P[0]; // This is fine.
double y = P[1]; // This is fine too.
}
This attribute does not create a new type (and so it not part of the type
system), and so will only "propagate" through templates, auto, etc. by
optimizer deduction after inlining. This seems consistent with Intel's
implementation (thanks to Alexey for confirming the various Intel-compiler
behaviors).
As a final note, I would have chosen to call this aligned_value, not
align_value, for better naming consistency with the aligned attribute, but I
think it would be more useful to users to adopt Intel's name.
llvm-svn: 218910
Prior to GCC 4.4, __sync_fetch_and_nand was implemented as:
{ tmp = *ptr; *ptr = ~tmp & value; return tmp; }
but this was changed in GCC 4.4 to be:
{ tmp = *ptr; *ptr = ~(tmp & value); return tmp; }
in response to this change, support for sync_fetch_and_nand (and
sync_nand_and_fetch) was removed in r99522 in order to avoid miscompiling code
depending on the old semantics. However, at this point:
1. Many years have passed, and the amount of code relying on the old
semantics is likely smaller.
2. Through the work of many contributors, all LLVM backends have been updated
such that "atomicrmw nand" provides the newer GCC 4.4+ semantics (this process
was complete July of 2014 (added to the release notes in r212635).
3. The lack of this intrinsic is now a needless impediment to porting codes
from GCC to Clang (I've now seen several examples of this).
It is true, however, that we still set GNUC_MINOR to 2 (corresponding to GCC
4.2). To compensate for this, and to address the original concern regarding
code relying on the old semantics, I've added a warning that specifically
details the fact that the semantics have changed and that we provide the newer
semantics.
Fixes PR8842.
llvm-svn: 218905
Summary:
Currently, with struct my_struct { int x; method_ptr y; };
a call to foo(my_struct s) may end up dropping the last 4 bytes
of the method pointer for x86_64 NaCl and x32.
When checking Has64BitPointers, also check if the method pointer
straddles an eightbyte boundary and classify Hi as well as Lo if needed.
Test Plan: test/CodeGenCXX/x86_64-arguments-nacl-x32.cpp
Reviewers: dschuff, pavel.v.chupin
Subscribers: jfb
Differential Revision: http://reviews.llvm.org/D5555
llvm-svn: 218889
Summary: Commit r218863 broke this test case. This patch fixes it
by updating the expected output line. Should've been updated with
the original patch but for some reason it didn't fail during my
local make check.
Change-Id: I89ed28b37f67c34d1a5d28a3e47ae33d9a82a98f
llvm-svn: 218864
I couldn't get something /really/ obvious, and I imagine Richard Smith
might be able to provide some text explaining the sequence of steps
that's demonstrated by these files - but at least it's a bit simpler
now.
llvm-svn: 218840
Complex address expressions are no longer part of DIVariable, but
rather an extra argument to the debug intrinsics.
http://reviews.llvm.org/D4919
rdar://problem/17994491
llvm-svn: 218788
Complex address expressions are no longer part of DIVariable, but
rather an extra argument to the debug intrinsics.
http://reviews.llvm.org/D4919
rdar://problem/17994491
llvm-svn: 218777
The Cortex-M7 has 3 options for its FPU: none, FPv5-SP-D16 and
FPv5-DP-D16. FPv5 has the same instructions as FP-ARMv8, so it can be
modeled using the same target feature, and all double-precision
operations are already disabled by the fp-only-sp target features.
llvm-svn: 218748
This patch implements collapsing of the loops (in particular, in
presense of clause 'collapse'). It calculates number of iterations N
and expressions nesessary to calculate the nested loops counters
values based on new iteration variable (that goes from 0 to N-1)
in Sema. It also adds Codegen for 'omp simd', which uses
(and tests) this feature.
Differential Revision: http://reviews.llvm.org/D5184
llvm-svn: 218743
When generating coverage regions, we were doing a linear search
through the existing regions in order to try to merge related ones.
Most of the time this would find what it was looking for in a small
number of steps and it wasn't a big deal, but in cases with many
regions and few mergeable ones this leads to an absurd compile time
regression.
This changes the coverage mapping logic to do a single sort and then
merge as we go, which is a bit simpler and about 100 times faster.
I've also added FIXMEs on a couple of behaviours that seem a little
suspect, while keeping them behaving as they were - I'll look into
these soon.
The test changes here are mostly tedious reorganization, because the
ordering of regions we output has become slightly (but not completely)
more consistent from the almost completely arbitrary ordering we got
before.
llvm-svn: 218738
being on by default. -fno-cxx-modules can still be used to enable C modules but
not C++ modules, but C++ modules is not significantly less stable than C
modules any more.
Also remove some of the scare words from the modules documentation. We're
certainly not going to remove modules support (though we might change the
interface), and it works well enough to bootstrap and build lots of
non-trivial code.
Note that this does not represent a commitment to the current interface nor
implementation, and we still intend to follow whatever direction the C and C++
committees take regarding modules support.
llvm-svn: 218717
In code-completion, don't assume there is a MacroInfo for everything,
since we aren't serializing the def corresponding to a later #undef in
the same module. Also setup the HadMacro bit correctly for undefs to
avoid an assertion failure.
rdar://18416901
llvm-svn: 218694
r218624 implemented target inference for implicit special members. However,
other entities can be implicit - for example intrinsics. These can not have
inference running on them, so they should be marked host device as before. This
is the safest and most flexible setting, since by construction these functions
don't invoke anything, and we'd like them to be invokable from both host and
device code. LLVM's intrinsics definitions (where these intrinsics come from in
the case of CUDA/NVPTX) have no notion of target, so both host and device
intrinsics can be supported this way.
llvm-svn: 218688
Empty records do not always have size equivalent to their alignment.
They only do so when their alignment is at least as large as the minimum
empty struct size: 1 byte in C++ and 4 bytes in C.
llvm-svn: 218661
Clang warns (treated as error by default, but still ignored in system headers)
when passing non-POD arguments to variadic functions, and generates a trap
instruction to crash the program if that code is ever run.
Unfortunately, MSVC happily generates code for such calls without a warning,
and there is code in system headers that use it.
This makes Clang not insert the trap instruction when in -fms-compatibility
mode, while still generating the warning/error message.
Differential Revision: http://reviews.llvm.org/D5492
llvm-svn: 218640
As PR20495 demonstrates, Clang currenlty infers the CUDA target (host/device,
etc) for implicit members (constructors, etc.) incorrectly. This causes errors
and even assertions in Clang when compiling code (assertions in C++11 mode where
implicit move constructors are added into the mix).
Fix the problem by inferring the target from the methods the implicit member
should call (depending on its base classes and fields).
llvm-svn: 218624
Fixes incorrect codegen when devirtualization is aborted due to covariant return types.
Differential Revision: http://reviews.llvm.org/D5321
llvm-svn: 218602
Clang uses two types to talk about a C++ class, the
NonVirtualBaseLLVMType and the LLVMType. Previously, we would allow one
of these to be packed and the other not.
This is problematic. If both don't agree on a common subset of fields,
then routines like getLLVMFieldNo will point to the wrong field. Solve
this by copying the 'packed'-ness of the complete type to the
non-virtual subobject. For this to work, we need to take into account
the non-virtual subobject's size and alignment when we are computing the
layout of the complete object.
This fixes PR21089.
llvm-svn: 218577
It makes no sense to link in sanitizer runtimes in this case: the user
probably doesn't want to see any system/toolchain libs in his link if he
provides these flags, and the link will most likely fail anyway - as sanitizer
runtimes depend on libpthread, libdl, libc etc.
Also, see discussion in https://code.google.com/p/address-sanitizer/issues/detail?id=344
llvm-svn: 218541
If a base class declares a destructor, we will add the implicit
destructor for the subclass in
ActOnFields -> AddImplicitlyDeclaredMembersToClass
But in Objective C++, we did not compute whether we have a trivial
destructor until after that in
CXXRecordDecl::completeDefinition()
This was leading to a mismatch between the class, which thought it had
no trivial destructor, and the CXXDestructorDecl, which considered
itself trivial. It turns out the reason we delayed setting this until
completeDefinition() was for a warning that has since been removed as
part of -Warc-abi, so we just do it eagerly now.
llvm-svn: 218520
(clang crashed in CodeGen in llvm::Module::getNamedValue on
thread_local std::unique_ptr<int>).
Differential Revision: http://reviews.llvm.org/D5353
llvm-svn: 218503
In addition to __builtin_assume_aligned, GCC also supports an assume_aligned
attribute which specifies the alignment (and optional offset) of a function's
return value. Here we implement support for the assume_aligned attribute by making
use of the @llvm.assume intrinsic.
llvm-svn: 218500
AFAICT the semantics of frem match libm's fmod.
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
Reviewed-by: Tom Stellard <tom@stellard.net>
llvm-svn: 218488
we were failing to find that bit-field when performing integer promotions. This
brings us closer to following the standard, and closer to GCC.
In C, this change is technically a regression: we get bit-field promotions
completely wrong in C, promoting cases that are categorically not bit-field
designators. This change makes us do so slightly more consistently, though.
llvm-svn: 218428
Use the same environment when invoking llvm-config from lit.cfg as
will be used when running tests, so that ASAN_OPTIONS, INCLUDE, etc.
are present.
llvm-svn: 218404
Fixes PR21027. The MIDL compiler produces code that does this.
If we wanted to improve the warning, I think we could do this:
void __stdcall f(); // Don't warn without -Wstrict-prototypes.
void g() {
f(); // Might warn, the user probably meant for f to take no args.
f(1, 2, 3); // Warn, we have no idea what args f takes.
f(1); // Error, this is insane, one of these calls is broken.
}
Reviewers: thakis
Differential Revision: http://reviews.llvm.org/D5481
llvm-svn: 218394
A record which contains a flexible array member is itself a flexible
array member. A struct which contains such a record should also
consider itself to be a flexible array member.
llvm-svn: 218378
r218292 reverted r197496 because it broke things. In addition to breaking
things, r197496 also made all traits starting with __is_ revertible.
Reinstantiate that part of r197496 because code out there (e.g. libc++) depends
on this behavior. Fixes PR21045.
llvm-svn: 218365
Usually, overriding a virtual function defined in a virtual base
required emission of a vtordisp slot in the record. However no vtordisp
is needed if the overriding function is pure; it should be impossible to
observe the pure virtual method.
This fixes PR21046.
llvm-svn: 218340
lists. Since the fields are inititalized one at a time, using a field with
lower index to initialize a higher indexed field should not be warned on.
llvm-svn: 218339
lexer, add the token buffer underneath the caching lexer where possible and
push the tokens directly into the caching lexer otherwise. We previously
put the lexer into a corrupted state where we could not guarantee to provide
the tokens in the right order and would sometimes assert.
llvm-svn: 218333
that function, and apart from being slow, this is unnecessary: ADL can trigger
instantiations that are not permitted here. The standard isn't *completely*
clear here, but this seems like the intent, and in any case this approach is
permitted by [temp.inst]p7.
llvm-svn: 218330
On further investigation, COMDATs should work with .ctors, and the issue
I was hitting probably reproduces with .init_array.
This reverts commit r218287.
llvm-svn: 218313
Don't mangle all casts in expressions as "cv", use the appropriate
encoding which corresponds to a specific cast.
This fixes PR21034.
Differential Revision: http://reviews.llvm.org/D5453
llvm-svn: 218293
In particular, pre-.init_array ELF uses the .ctors section mechanism.
MinGW COFF also uses .ctors, now that I think about it. Therefore,
restrict this optimization to the two platforms that are currently known
to work: ELF with .init_array and COFF with .CRT$XCU.
llvm-svn: 218287
We need to walk the class hierarchy twice: once in depth-first base
specifier order for mangling and again in depth-first layout order for
vftable layout.
Vftable layout seems to depend on the full path from the most derived
class to the base containing the vfptr.
Fixes PR21031.
llvm-svn: 218285
Summary:
Vectors are normally 16-byte aligned, however the O32 ABI enforces a
maximum alignment of 8-bytes since the base of the stack is 8-byte aligned.
Previously, this was enforced on the caller side, but not on the callee side.
This fixes the output of OpenCL's printf when given vectors.
Reviewers: atanasyan
Reviewed By: atanasyan
Subscribers: llvm-commits, pekka.jaaskelainen
Differential Revision: http://reviews.llvm.org/D5433
llvm-svn: 218248
This patch adds codegen for constructs:
#pragma omp critical [name]
<body>
It generates global variable ".gomp_critical_user_[name].var" of type int32[8]. Then it generates library call "kmpc_critical(loc, gtid, .gomp_critical_user_[name].var)", code for <body> statement and final call "kmpc_end_critical(loc, gtid, .gomp_critical_user_[name].var)".
Differential Revision: http://reviews.llvm.org/D5202
llvm-svn: 218239
Summary:
This fixes PR20023. In order to implement this scoping rule, we piggy
back on the existing LabelDecl machinery, by creating LabelDecl's that
will carry the "internal" name of the inline assembly label, which we
will rewrite the asm label to.
Reviewers: rnk
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D4589
llvm-svn: 218230
This commit makes two changes:
- Remove the push and pop instructions that were saving and restoring %ebx
before and after cpuid in 32-bit pic mode. We were doing this to ensure we
don't lose the GOT address in pic register %ebx, but this isn't necessary
because the GOT address is kept in a virtual register.
- In 64-bit mode, preserve base register %rbx around cpuid.
This fixes PR20311 and rdar://problem/17686779.
llvm-svn: 218173
According to lore, we used to verifier-fail on:
void __thiscall f();
int main() { f(1); }
So that's fixed now. System headers use prototype-less __stdcall functions,
so make that a warning that's DefaultError -- then it fires on regular code
but is suppressed in system headers.
Since it's used in system headers, we have codegen tests for this; massage
them slightly so that they still compile.
llvm-svn: 218166
This patch makes sure that the dllexport attribute is transferred to the alias when such alias is created. It only affects the Itanium ABI because for the MSVC ABI a workaround is in place to not generate aliases of dllexport ctors/dtors.
A new CodeGenModule function is provided, CodeGenModule::setAliasAttributes, to factor the code for transferring attributes to aliases.
llvm-svn: 218159
Clang can already handle
-------------------------------------------
struct S {
static const int x;
};
template<typename T> struct U {
static const int k;
};
template<typename T> const int U<T>::k = T::x;
const int S::x = 42;
extern const int *f();
const int *g() { return &U<S>::k; }
int main() {
return *f() + U<S>::k;
}
const int *f() { return &U<S>::k; }
-------------------------------------------
since r217264 which puts the .inint_array section in the same COMDAT
as the variable.
This patch allows the linker to more easily delete some dead code and data by
putting the guard variable and init function in the same COMDAT.
This is a fixed version of r218089.
llvm-svn: 218141
They are added to adxintrin.h but outside __ADX__ block.
These intrinics generates adc and sbb correspondingly that were available before ADX
llvm-svn: 218118
The field is defined as:
If the third field is present, non-null, and points to a global variable or function, the initializer function will only run if the associated data from the current module is not discarded.
And without COMDATs we can't implement that.
llvm-svn: 218097
Clang can already handle
-------------------------------------------
struct S {
static const int x;
};
template<typename T> struct U {
static const int k;
};
template<typename T> const int U<T>::k = T::x;
const int S::x = 42;
extern const int *f();
const int *g() { return &U<S>::k; }
int main() {
return *f() + U<S>::k;
}
const int *f() { return &U<S>::k; }
-------------------------------------------
since r217264 which puts the .inint_array section in the same COMDAT
as the variable.
This patch allows the linker to more easily delete some dead code and data by
putting the guard variable and init function in the same COMDAT.
llvm-svn: 218089
warns when a guarded variable is passed by reference as a function argument.
This is released as a separate warning flag, because it could potentially
break existing code that uses thread safety analysis.
llvm-svn: 218087
CodeGen would try to come up with an LLVM IR type for a pointer to
member type on the way to forming an LLVM IR type for a pointer to
pointer to member type.
However, if the pointer to member representation has not been locked in yet,
we would not be able to come up with a pointer to member IR type.
In these cases, make the pointer to member type an incomplete type.
This will make the pointer to pointer to member type a pointer to an
incomplete type. If the class eventually obtains an inheritance model,
we will make the pointer to member type represent the actual inheritance
model.
Differential Revision: http://reviews.llvm.org/D5373
llvm-svn: 218084
David Majnemer