Condense the ObjCKIND and CXXKIND options into just KIND, since the
language was already specified on a per-symbol basis and this
information was redundant. This only changes the internal
representation; naturally the libclang interface remains the same.
llvm-svn: 264423
Till now, preserve_mostcc/preserve_allcc calling convention attributes were only
available at the LLVM IR level. This patch adds attributes for
preserve_mostcc/preserve_allcc calling conventions to the C/C++ front-end.
The code was mostly written by Juergen Ributzka.
I just added support for the AArch64 target and tests.
Differential Revision: http://reviews.llvm.org/D18025
llvm-svn: 263647
Clauses with post-update expressions always have pre-init statement. So
OMPClauseWithPreInit now is the base for OMPClauseWithPostUpdate.
llvm-svn: 262696
This is a sad workaround for the lack of plugin support in libclang. Depends
on D17807, a tools-extra change that also contains the test case.
This is designed to be easy to remove again if libclang ever grows proper
plugin support.
Differential Revision: http://reviews.llvm.org/D17808
llvm-svn: 262596
Add parsing, sema analysis and serialization/deserialization for 'declare reduction' construct.
User-defined reductions are defined as
#pragma omp declare reduction( reduction-identifier : typename-list : combiner ) [initializer ( initializer-expr )]
These custom reductions may be used in 'reduction' clauses of OpenMP constructs. The combiner specifies how partial results can be combined into a single value. The
combiner can use the special variable identifiers omp_in and omp_out that are of the type of the variables being reduced with this reduction-identifier. Each of them will
denote one of the values to be combined before executing the combiner. It is assumed that the special omp_out identifier will refer to the storage that holds the resulting
combined value after executing the combiner.
As the initializer-expr value of a user-defined reduction is not known a priori the initializer-clause can be used to specify one. Then the contents of the initializer-clause
will be used as the initializer for private copies of reduction list items where the omp_priv identifier will refer to the storage to be initialized. The special identifier
omp_orig can also appear in the initializer-clause and it will refer to the storage of the original variable to be reduced.
Differential Revision: http://reviews.llvm.org/D11182
llvm-svn: 262582
This is like r262493, but for pragma detect_mismatch instead of pragma comment.
The two pragmas have similar behavior, so use the same approach for both.
llvm-svn: 262506
`#pragma comment` was handled by Sema calling a function on ASTConsumer, and
CodeGen then implementing this function and writing things to its output.
Instead, introduce a PragmaCommentDecl AST node and hang one off the
TranslationUnitDecl for every `#pragma comment` line, and then use the regular
serialization machinery. (Since PragmaCommentDecl has codegen relevance, it's
eagerly deserialized.)
http://reviews.llvm.org/D17799
llvm-svn: 262493
OpenMP 4.5 allows to privatize non-static data members of current class
in non-static member functions. Patch supports codegen for non-static
data members in 'reduction' clauses.
llvm-svn: 262460
This behavior is enabled when the new CXTranslationUnit_KeepGoing
option is passed to clang_parseTranslationUnit{,2}. It is geared
towards use by IDEs and similar consumers of the clang-c API where
fatal errors may arise when parsing incomplete code mid-edit, or
when include paths are not properly configured yet. In such situations
one still wants to get as much information as possible about a TU.
Previously, the semantic analysis would not instantiate templates
or report additional fatal errors after the first fatal error was
encountered.
Fixes PR24268.
Patch by Milian Wolff.
llvm-svn: 262318
OpenMP 4.5 allows to privatize non-static member decls in non-static
member functions. Patch captures such decls by reference in general (for
bitfields, by value) and then operates with this capture. For bitfields,
at the end of codegen for lastprivates original bitfield is updated with the value of captured copy.
llvm-svn: 261824
Expressions inside 'schedule'|'dist_schedule' clause must be captured in
combined directives to avoid possible crash during codegen. Patch
improves handling of such constructs
llvm-svn: 260954
These codepaths would generate warnings with GCC on linux even though the switch
was covered. Add llvm_unreachable markers to indicate that the switch should be
covered. NFC.
llvm-svn: 260865
OMPCapturedExprDecl allows caopturing not only of fielddecls, but also
other expressions. It also allows to simplify codegen for several
clauses.
llvm-svn: 260492
OpenMP 4.5 introduces privatization of non-static data members of current class in non-static member functions.
To correctly handle such kind of privatization a new (pseudo)declaration VarDecl-based node is added. It allows to reuse an existing code for capturing variables in Lambdas/Block/Captured blocks of code for correct privatization and codegen.
llvm-svn: 260077
Summary:
This patch adds parsing + sema for the target parallel for directive along with testcases.
Reviewers: ABataev
Differential Revision: http://reviews.llvm.org/D16759
llvm-svn: 259654
Add "enum ObjCPropertyQueryKind" to a few APIs that used to only take the name
of the property: ObjCPropertyDecl::findPropertyDecl,
ObjCContainerDecl::FindPropertyDeclaration,
ObjCInterfaceDecl::FindPropertyVisibleInPrimaryClass,
ObjCImplDecl::FindPropertyImplDecl, and Sema::ActOnPropertyImplDecl.
ObjCPropertyQueryKind currently has 3 values:
OBJC_PR_query_unknown, OBJC_PR_query_instance, OBJC_PR_query_class
This extra parameter specifies that we are looking for an instance property with
the given name, or a class property with the given name, or any property with
the given name (if both exist, the instance property will be returned).
rdar://23891898
llvm-svn: 259070
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html
"This is the way [autoconf] ends
Not with a bang but a whimper."
-T.S. Eliot
Reviewers: chandlerc, grosbach, bob.wilson, echristo
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D16472
llvm-svn: 258862
Summary:
This patch adds parsing + sema for the target parallel directive and its clauses along with testcases.
Reviewers: ABataev
Differential Revision: http://reviews.llvm.org/D16553
Rebased to current trunk and updated test cases.
llvm-svn: 258832
Summary:
This patch adds parsing + sema for the defaultmap clause associated with the target directive (among others).
Reviewers: ABataev
Differential Revision: http://reviews.llvm.org/D16527
llvm-svn: 258817
Summary:
Support for OpenCL 2.0 pipe type.
This is a bug-fix version for bader's patch reviews.llvm.org/D14441
Reviewers: pekka.jaaskelainen, Anastasia
Subscribers: bader, Anastasia, cfe-commits
Differential Revision: http://reviews.llvm.org/D15603
llvm-svn: 257254
When reparsing a translation unit with preamble generation turned on,
no includes are found. This is due to the fact that all SLocs from
AST/PCH files are skipped as they are 'loaded', and inclusions from a
preamble are also 'loaded'. So, in case a file has a preamble, it first
needs to process those loaded inclusions, and then check for any local
inclusions. This latter one is for any includes that are not part of the
preamble, like includes half-way through a file.
This fixes PR24748.
Differential Revision: http://reviews.llvm.org/D14329
llvm-svn: 256939
Doing so required separating them so that the former doesn't inherit
from the latter anymore. Investigating that, it became clear that the
inheritance wasn't actually providing real value in any case.
So also:
- Remove a bunch of redundant functions (getExplicitTemplateArgs,
getOptionalExplicitTemplateArgs) on various Expr subclasses which
depended on the inheritance relationship.
- Switched external callers to use pre-existing accessors that return the
data they're actually interested in (getTemplateArgs,
getNumTemplateArgs, etc).
- Switched internal callers to use pre-existing getTemplateKWAndArgsInfo.
llvm-svn: 256359
Summary:
The current default is to create the preamble on the first reparse, aka
second parse. This is useful for clients that do not want to block when
opening a file because serializing the preamble takes a bit of time.
However, this makes the reparse much more expensive and that may be on the
critical path as it's the first interaction a user has with the source code.
YouCompleteMe currently optimizes for the first code interaction by parsing
the file twice when loaded. That's just unnecessarily slow and this flag
helps to avoid that.
Reviewers: doug.gregor, klimek
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D15490
llvm-svn: 255635
These attributes were previously unexposed. Expose them through the libclang
interfaces. Add tests that cover both the MSVC spelling and the GNU spelling.
llvm-svn: 255273
The complete dtor is only emitted when there is a virtual destructor. The test
itself was incorrect, so the issue in the code was not noticed.
llvm-svn: 255225
OpenMP 4.5 adds directives 'taskloop' and 'taskloop simd'. These directives support clause 'num_tasks'. Patch adds parsing/semantic analysis for this clause.
llvm-svn: 255008
OpenMP 4.5 adds 'taksloop' and 'taskloop simd' directives, which have 'grainsize' clause. Patch adds parsing/sema analysis of this clause.
llvm-svn: 254903
OpenMP 4.5 adds 'taskloop' and 'taskloop simd' directives. These directives have new 'nogroup' clause. Patch adds basic parsing/sema support for this clause.
llvm-svn: 254899
OpenMP 4.5 defines new clause 'priority' for 'task', 'taskloop' and 'taskloop simd' directives. Added parsing and sema analysis for 'priority' clause in 'task' and 'taskloop' directives.
llvm-svn: 254398
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
to allow them to explicitly opt into data recursion despite having overridden
Traverse*Stmt or Traverse*Expr. Use this to reintroduce data recursion to the
one place that lost it when DataRecursiveASTVisitor was removed.
llvm-svn: 254041
Right now clang_Cursor_getMangling will attempt to mangle any
declaration, even if the declaration isn't mangled (extern C). This
results in a partially mangled name which isn't useful for much. This
patch makes clang_Cursor_getMangling return an empty string if the
declaration isn't mangled.
Patch by Michael Wu <mwu@mozilla.com>.
llvm-svn: 253909
This provides both a more uniform interface and makes libclang behave like
clang tooling wrt relative paths against argv[0]. This is necessary for
finding paths to a c++ standard library relative to a clang binary given
in a compilation database. It can also be used to find paths relative to
libclang.so if the full path to it is passed in.
Differential Revision: http://reviews.llvm.org/D14695
llvm-svn: 253466
This function permits the mangling of a C++ 'structor. Depending on the ABI and
the declaration, the declaration may contain more than one associated symbol for
a given declaration. This allows the consumer to retrieve all of the associated
symbols for the declaration the cursor points to.
llvm-svn: 252853
This allows the return of a set of CXStrings from libclang. This is setup work
for an upcoming change to permit returning multiple mangled symbols.
llvm-svn: 252852
This new builtin template allows for incredibly fast instantiations of
templates like std::integer_sequence.
Performance numbers follow:
My work station has 64 GB of ram + 20 Xeon Cores at 2.8 GHz.
__make_integer_seq<std::integer_sequence, int, 90000> takes 0.25
seconds.
std::make_integer_sequence<int, 90000> takes unbound time, it is still
running. Clang is consuming gigabytes of memory.
Differential Revision: http://reviews.llvm.org/D13786
llvm-svn: 252036
Summary: It breaks the build for the ASTMatchers
Subscribers: klimek, cfe-commits
Differential Revision: http://reviews.llvm.org/D13893
llvm-svn: 250827
LLVM_SUBMIT_VERSION and LLVM_SUBMIT_SUBVERSION are commonly used variable names in the autoconf build system. They seem to have leeched into clang's CMake in a few places, and should just be replaced by the LLVM_VERSION_* variables where appropriate.
llvm-svn: 250246
Right now clang_Cursor_getMangling will attempt to mangle any
declaration, even if the declaration isn't mangled (extern C). This
results in a partially mangled name which isn't useful for much. This
patch makes clang_Cursor_getMangling return an empty string if the
declaration isn't mangled.
Patch by Michael Wu <mwu@mozilla.com>.
llvm-svn: 249639
Right now clang_Cursor_getMangling will attempt to mangle any
declaration, even if the declaration isn't mangled (extern "C"). This
results in a partially mangled name which isn't useful for much. This
patch makes clang_Cursor_getMangling return an empty string if the
declaration isn't mangled.
Patch by Michael Wu <mwu@mozilla.com>.
llvm-svn: 249437
- Remove virtual SC_OpenCLWorkGroupLocal storage type specifier
as it conflicts with static local variables now and prevents
diagnosing static local address space variables correctly.
- Allow static local and global variables (OpenCL2.0 s6.8 and s6.5.1).
- Improve diagnostics of allowed ASes for variables in different scopes:
(i) Global or static local variables have to be in global
or constant ASes (OpenCL1.2 s6.5, OpenCL2.0 s6.5.1);
(ii) Non-kernel function variables can't be declared in local
or constant ASes (OpenCL1.1 s6.5.2 and s6.5.3).
http://reviews.llvm.org/D13105
llvm-svn: 248906
Parsing and sema analysis for 'simd' clause in 'ordered' directive.
Description
If the simd clause is specified, the ordered regions encountered by any thread will use only a single SIMD lane to execute the ordered
regions in the order of the loop iterations.
Restrictions
An ordered construct with the simd clause is the only OpenMP construct that can appear in the simd region
llvm-svn: 248696
OpenMP 4.1 extends format of '#pragma omp ordered'. It adds 3 additional clauses: 'threads', 'simd' and 'depend'.
If no clause is specified, the ordered construct behaves as if the threads clause had been specified. If the threads clause is specified, the threads in the team executing the loop region execute ordered regions sequentially in the order of the loop iterations.
The loop region to which an ordered region without any clause or with a threads clause binds must have an ordered clause without the parameter specified on the corresponding loop directive.
llvm-svn: 248569
It used to work, but was accidentally broken by r179769.
The issue with decayed types was fixed by r190796.
So this patch partially reverts r179769, and adds more tests.
This also fixes PR 18669.
Patch by Sergey Kalinichev.
llvm-svn: 246778
to enable the use of external type references in the debug info
(a.k.a. module debugging).
The driver expands -gmodules to "-g -fmodule-format=obj -dwarf-ext-refs"
and passes that to cc1. All this does at the moment is set a flag
codegenopts.
http://reviews.llvm.org/D11958
llvm-svn: 246192
Adds parsing/sema analysis/serialization/deserialization for array sections in OpenMP constructs (introduced in OpenMP 4.0).
Currently it is allowed to use array sections only in OpenMP clauses that accepts list of expressions.
Differential Revision: http://reviews.llvm.org/D10732
llvm-svn: 245937
Add parsing/sema analysis for 'simdlen' clause in simd directives. Also add check that if both 'safelen' and 'simdlen' clauses are specified, the value of 'simdlen' parameter is less than the value of 'safelen' parameter.
llvm-svn: 245692
OpenMP 4.1 allows to use variables with reference types in all private clauses (private, firstprivate, lastprivate, linear etc.). Patch allows to use such variables and fixes codegen for linear variables with reference types.
llvm-svn: 245268
After r244870 flush() will only compare two null pointers and return,
doing nothing but wasting run time. The call is not required any more
as the stream and its SmallString are always in sync.
Thanks to David Blaikie for reviewing.
llvm-svn: 244928
In llvm commit r243581, a reverse range adapter was added which allows
us to change code such as
for (auto I = Fields.rbegin(), E = Fields.rend(); I != E; ++I) {
in to
for (const FieldDecl *I : llvm::reverse(Fields))
This commit changes a few of the places in clang which are eligible to use
this new adapter.
llvm-svn: 243663
OpenMP 4.1 introduces optional argument '(n)' for 'ordered' clause, where 'n' is a number of loops that immediately follow the directive.
'n' must be constant positive integer expressions and it must be less or equal than the number of the loops in the resulting loop nest.
Patch adds parsing and semantic analysis for this optional argument.
llvm-svn: 243635
This boilerplate code was necessary to move arguments between threads in
C++98, lambdas make this much easier. No functionality change intended.
llvm-svn: 243227
- introduces a new cc1 option -fmodule-format=[raw,obj]
with 'raw' being the default
- supports arbitrary module container formats that libclang is agnostic to
- adds the format to the module hash to avoid collisions
- splits the old PCHContainerOperations into PCHContainerWriter and
a PCHContainerReader.
Thanks to Richard Smith for reviewing this patch!
llvm-svn: 242499
NOTE: reverts r242077 to reinstate r242058, r242065, 242067
and includes fix for OS X test failures.
- Changed driver pipeline to compile host and device side of CUDA
files and incorporate results of device-side compilation into host
object file.
- Added a test for cuda pipeline creation in clang driver.
New clang options:
--cuda-host-only - Do host-side compilation only.
--cuda-device-only - Do device-side compilation only.
--cuda-gpu-arch=<ARCH> - specify GPU architecture for device-side
compilation. E.g. sm_35, sm_30. Default is sm_20. May be used more
than once in which case one device-compilation will be done per
unique specified GPU architecture.
Differential Revision: http://reviews.llvm.org/D9509
llvm-svn: 242085
The tests were failing on OS X.
Revert "[cuda] Driver changes to compile and stitch together host and device-side CUDA code."
Revert "Fixed regex to properly match '64' in the test case."
Revert "clang/test/Driver/cuda-options.cu REQUIRES clang-driver, at least."
llvm-svn: 242077
- Changed driver pipeline to compile host and device side of CUDA
files and incorporate results of device-side compilation into host
object file.
- Added a test for cuda pipeline creation in clang driver.
New clang options:
--cuda-host-only - Do host-side compilation only.
--cuda-device-only - Do device-side compilation only.
--cuda-gpu-arch=<ARCH> - specify GPU architecture for device-side
compilation. E.g. sm_35, sm_30. Default is sm_20. May be used more
than once in which case one device-compilation will be done per
unique specified GPU architecture.
Differential Revision: http://reviews.llvm.org/D9509
llvm-svn: 242058
One of the problems libclang tests has running under Windows is memory
allocated in libclang.dll but being freed in the test executable, possibly
by a different memory manager. This patch exposes a new export function,
clang_free(), used to free any allocated memory with the same libclang.dll
memory manager that allocated the memory.
http://reviews.llvm.org/D10949
Reviewed by Reid Kleckner, Douglas Gregor.
llvm-svn: 241789
This patch adds ObjectFilePCHContainerOperations uses the LLVM backend
to put the contents of a PCH into a __clangast section inside a COFF, ELF,
or Mach-O object file container.
This is done to facilitate module debugging by makeing it possible to
store the debug info for the types defined by a module alongside the AST.
rdar://problem/20091852
llvm-svn: 241620
Teach C++'s tentative parsing to handle specializations of Objective-C
class types (e.g., NSArray<NSString *>) as well as Objective-C
protocol qualifiers (id<NSCopying>) by extending type-annotation
tokens to handle this case. As part of this, remove Objective-C
protocol qualifiers from the declaration specifiers, which never
really made sense: instead, provide Sema entry points to make them
part of the type annotation token. Among other things, this properly
diagnoses bogus types such as "<NSCopying> id" which should have been
written as "id <NSCopying>".
Implements template instantiation support for, e.g., NSArray<T>*
in C++. Note that parameterized classes are not templates in the C++
sense, so that cannot (for example) be used as a template argument for
a template template parameter. Part of rdar://problem/6294649.
llvm-svn: 241545
Objective-C type arguments can be provided in angle brackets following
an Objective-C interface type. Syntactically, this is the same
position as one would provide protocol qualifiers (e.g.,
id<NSCopying>), so parse both together and let Sema sort out the
ambiguous cases. This applies both when parsing types and when parsing
the superclass of an Objective-C class, which can now be a specialized
type (e.g., NSMutableArray<T> inherits from NSArray<T>).
Check Objective-C type arguments against the type parameters of the
corresponding class. Verify the length of the type argument list and
that each type argument satisfies the corresponding bound.
Specializations of parameterized Objective-C classes are represented
in the type system as distinct types. Both specialized types (e.g.,
NSArray<NSString *> *) and unspecialized types (NSArray *) are
represented, separately.
llvm-svn: 241542
Produce type parameter declarations for Objective-C type parameters,
and attach lists of type parameters to Objective-C classes,
categories, forward declarations, and extensions as
appropriate. Perform semantic analysis of type bounds for type
parameters, both in isolation and across classes/categories/extensions
to ensure consistency.
Also handle (de-)serialization of Objective-C type parameter lists,
along with sundry other things one must do to add a new declaration to
Clang.
Note that Objective-C type parameters are typedef name declarations,
like typedefs and C++11 type aliases, in support of type erasure.
Part of rdar://problem/6294649.
llvm-svn: 241541
Parsing and sema analysis (without support for array sections in arguments) for 'depend' clause (used in 'task' directive, OpenMP 4.0).
llvm-svn: 240409
The patch is generated using this command:
$ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
work/llvm/tools/clang
To reduce churn, not touching namespaces spanning less than 10 lines.
llvm-svn: 240270
A PCHContainerOperations abstract interface provides operations for
creating and unwrapping containers for serialized ASTs (precompiled
headers and clang modules). The default implementation is
RawPCHContainerOperations, which uses a flat file for the output.
The main application for this interface will be an
ObjectFilePCHContainerOperations implementation that uses LLVM to
wrap the module in an ELF/Mach-O/COFF container to store debug info
alongside the AST.
rdar://problem/20091852
llvm-svn: 240225
Added parsing, sema analysis and codegen for '#pragma omp taskgroup' directive (OpenMP 4.0).
The code for directive is generated the following way:
#pragma omp taskgroup
<body>
void __kmpc_taskgroup(<loc>, thread_id);
<body>
void __kmpc_end_taskgroup(<loc>, thread_id);
llvm-svn: 240011
Based on previous discussion on the mailing list, clang currently lacks support
for C99 partial re-initialization behavior:
Reference: http://lists.cs.uiuc.edu/pipermail/cfe-dev/2013-April/029188.html
Reference: http://www.open-std.org/jtc1/sc22/wg14/www/docs/dr_253.htm
This patch attempts to fix this problem.
Given the following code snippet,
struct P1 { char x[6]; };
struct LP1 { struct P1 p1; };
struct LP1 l = { .p1 = { "foo" }, .p1.x[2] = 'x' };
// this example is adapted from the example for "struct fred x[]" in DR-253;
// currently clang produces in l: { "\0\0x" },
// whereas gcc 4.8 produces { "fox" };
// with this fix, clang will also produce: { "fox" };
Differential Review: http://reviews.llvm.org/D5789
llvm-svn: 239446
'schedule' clause for combined directives requires additional processing. Special helper variable is generated, that is captured in the outlined parallel region for 'parallel for' region. This captured variable is used to store chunk expression from the 'schedule' clause in this 'parallel for' region.
llvm-svn: 237100
clang::MacroDefinition now models the currently-defined value of a macro. The
previous MacroDefinition type, which represented a record of a macro definition
directive for a detailed preprocessing record, is now called MacroDefinitionRecord.
llvm-svn: 236400
Modules builds fundamentally have a non-linear macro history. In the interest
of better source fidelity, represent the macro definition information
faithfully: we have a linear macro directive history within each module, and at
any point we have a unique "latest" local macro directive and a collection of
visible imported directives. This also removes the attendent complexity of
attempting to create a correct MacroDirective history (which we got wrong
in the general case).
No functionality change intended.
llvm-svn: 236176
Emits the following code for the clause at the beginning of the outlined function for implicit threads:
if (<not a master thread>) {
...
<thread local copy of var> = <master thread local copy of var>;
...
}
<sync point>;
Checking for a non-master thread is performed by comparing of the address of the thread local variable with the address of the master's variable. Master thread always uses original variables, so you always know the address of the variable in the master thread.
Differential Revision: http://reviews.llvm.org/D9026
llvm-svn: 235075
#pragma omp for lastprivate(<var>)
for (i = a; i < b; ++b)
<BODY>;
This construct is translated into something like:
<last_iter> = alloca i32
<lastprivate_var> = alloca <type>
<last_iter> = 0
; No initializer for simple variables or a default constructor is called for objects.
; For arrays perform element by element initialization by the call of the default constructor.
...
OMP_FOR_START(...,<last_iter>, ..); sets <last_iter> to 1 if this is the last iteration.
<BODY>
...
OMP_FOR_END
if (<last_iter> != 0) {
<var> = <lastprivate_var> ; Update original variable with the lastprivate value.
}
call __kmpc_cancel_barrier() ; an implicit barrier to avoid possible data race.
Differential Revision: http://reviews.llvm.org/D8658
llvm-svn: 235074