Commit Graph

823 Commits

Author SHA1 Message Date
Alex Lorenz 00aee43734 [Serialization] Serialize DependentSizedExtVectorType
rdar://30659700

Differential Revision: https://reviews.llvm.org/D31134

llvm-svn: 298493
2017-03-22 10:04:48 +00:00
Duncan P. N. Exon Smith 030d7d6daa Reapply "Modules: Cache PCMs in memory and avoid a use-after-free"
This reverts commit r298185, effectively reapplying r298165, after fixing the
new unit tests (PR32338).  The memory buffer generator doesn't null-terminate
the MemoryBuffer it creates; this version of the commit informs getMemBuffer
about that to avoid the assert.

Original commit message follows:

----

Clang's internal build system for implicit modules uses lock files to
ensure that after a process writes a PCM it will read the same one back
in (without contention from other -cc1 commands).  Since PCMs are read
from disk repeatedly while invalidating, building, and importing, the
lock is not released quickly.  Furthermore, the LockFileManager is not
robust in every environment.  Other -cc1 commands can stall until
timeout (after about eight minutes).

This commit changes the lock file from being necessary for correctness
to a (possibly dubious) performance hack.  The remaining benefit is to
reduce duplicate work in competing -cc1 commands which depend on the
same module.  Follow-up commits will change the internal build system to
continue after a timeout, and reduce the timeout.  Perhaps we should
reconsider blocking at all.

This also fixes a use-after-free, when one part of a compilation
validates a PCM and starts using it, and another tries to swap out the
PCM for something new.

The PCMCache is a new type called MemoryBufferCache, which saves memory
buffers based on their filename.  Its ownership is shared by the
CompilerInstance and ModuleManager.

- The ModuleManager stores PCMs there that it loads from disk, never
touching the disk if the cache is hot.

- When modules fail to validate, they're removed from the cache.

- When a CompilerInstance is spawned to build a new module, each
already-loaded PCM is assumed to be valid, and is frozen to avoid
the use-after-free.

- Any newly-built module is written directly to the cache to avoid the
round-trip to the filesystem, making lock files unnecessary for
correctness.

Original patch by Manman Ren; most testcases by Adrian Prantl!

llvm-svn: 298278
2017-03-20 17:58:26 +00:00
Renato Golin f1966cf646 Revert "Modules: Cache PCMs in memory and avoid a use-after-free"
This reverts commit r298165, as it broke the ARM builds.

llvm-svn: 298185
2017-03-18 12:31:32 +00:00
Duncan P. N. Exon Smith 079c40e886 Modules: Cache PCMs in memory and avoid a use-after-free
Clang's internal build system for implicit modules uses lock files to
ensure that after a process writes a PCM it will read the same one back
in (without contention from other -cc1 commands).  Since PCMs are read
from disk repeatedly while invalidating, building, and importing, the
lock is not released quickly.  Furthermore, the LockFileManager is not
robust in every environment.  Other -cc1 commands can stall until
timeout (after about eight minutes).

This commit changes the lock file from being necessary for correctness
to a (possibly dubious) performance hack.  The remaining benefit is to
reduce duplicate work in competing -cc1 commands which depend on the
same module.  Follow-up commits will change the internal build system to
continue after a timeout, and reduce the timeout.  Perhaps we should
reconsider blocking at all.

This also fixes a use-after-free, when one part of a compilation
validates a PCM and starts using it, and another tries to swap out the
PCM for something new.

The PCMCache is a new type called MemoryBufferCache, which saves memory
buffers based on their filename.  Its ownership is shared by the
CompilerInstance and ModuleManager.

  - The ModuleManager stores PCMs there that it loads from disk, never
    touching the disk if the cache is hot.

  - When modules fail to validate, they're removed from the cache.

  - When a CompilerInstance is spawned to build a new module, each
    already-loaded PCM is assumed to be valid, and is frozen to avoid
    the use-after-free.

  - Any newly-built module is written directly to the cache to avoid the
    round-trip to the filesystem, making lock files unnecessary for
    correctness.

Original patch by Manman Ren; most testcases by Adrian Prantl!

llvm-svn: 298165
2017-03-17 22:55:13 +00:00
Duncan P. N. Exon Smith 3cb183b121 Modules: Optimize bitcode encoding of diagnostic state
Since bitcode uses VBR encoding, large numbers are more expensive than
small ones.  Instead of emitting a UINT_MAX sentinel after each sequence
of state-change pairs, emit the size of the sequence as a prefix.

This should have no functionality change besides saving bits from the
encoding.

llvm-svn: 297770
2017-03-14 19:31:27 +00:00
Duncan P. N. Exon Smith 60fa28882e Modules: Use hash of PCM content for SIGNATURE
Change ASTFileSignature from a random 32-bit number to the hash of the
PCM content.

  - Move definition ASTFileSignature to Basic/Module.h so Module and
    ASTSourceDescriptor can use it.

  - Change the signature from uint64_t to std::array<uint32_t,5>.

  - Stop using (saving/reading) the size and modification time of PCM
    files when there is a valid SIGNATURE.

  - Add UNHASHED_CONTROL_BLOCK, and use it to store the SIGNATURE record
    and other records that shouldn't affect the hash.  Because implicit
    modules reuses the same file for multiple levels of -Werror, this
    includes DIAGNOSTIC_OPTIONS and DIAG_PRAGMA_MAPPINGS.

This helps to solve a PCH + implicit Modules dependency issue: PCH files
are handled by the external build system, whereas implicit modules are
handled by internal compiler build system.  This prevents invalidating a
PCH when the compiler overwrites a PCM file with the same content
(modulo the diagnostic differences).

Design and original patch by Manman Ren!

llvm-svn: 297655
2017-03-13 18:45:08 +00:00
Richard Smith df054d3d22 C++ DR1611, 1658, 2180: implement "potentially constructed subobject" rules for special member functions.
Essentially, as a base class constructor does not construct virtual bases, such
a constructor for an abstract class does not need the corresponding base class
construction to be valid, and likewise for destructors.

This creates an awkward situation: clang will sometimes generate references to
the complete object and deleting destructors for an abstract class (it puts
them in the construction vtable for a derived class). But we can't generate a
"correct" version of these because we can't generate references to base class
constructors any more (if they're template specializations, say, we might not
have instantiated them and can't assume any other TU will emit a copy).
Fortunately, we don't need to, since no correct program can ever invoke them,
so instead emit symbols that just trap.

We should stop emitting references to these symbols, but still need to emit
definitions for compatibility.

llvm-svn: 296275
2017-02-25 23:53:05 +00:00
Richard Trieu b6adf54204 Part of adding an improved ODR checker.
Reserve a spot for ODR hash in CXXRecordDecl and in its modules storage.
Default the hash value to 0 for all classes.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 295533
2017-02-18 02:09:28 +00:00
Richard Trieu dc4cb02470 Revert r295421, new ODR checker for modules, to fix build bot.
llvm-svn: 295427
2017-02-17 07:19:24 +00:00
Richard Trieu cb6b72628e Add better ODR checking for modules.
A slightly weaker form of ODR checking than previous attempts, but hopefully
won't break the modules build bot.  Future work will be needed to catch all
cases.

When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation.  Previously, only a small number of such
violations were detected.  This patch provides a stronger check based on
AST nodes.

The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream.  This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.

When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared.  Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.

The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops.  For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed.  As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.

Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 295421
2017-02-17 05:54:30 +00:00
Richard Trieu e55fb7f6f1 Revert r295284: Add better ODR checking for modules.
Fix modules build bot.

llvm-svn: 295293
2017-02-16 07:09:18 +00:00
Richard Trieu f351ac8987 Add better ODR checking for modules.
Recommit r293585 that was reverted in r293611 with new fixes.  The previous
issue was determined to be an overly aggressive AST visitor from forward
declared objects.  The visitor will now only deeply visit certain Decl's and
only do a shallow information extraction from all other Decl's.

When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation.  Previously, only a small number of such
violations were detected.  This patch provides a stronger check based on
AST nodes.

The information needed to uniquely identify an object is taken from the AST and
put into a one-dimensional byte stream.  This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.

When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared.  Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.

The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops.  For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed.  As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.

Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 295284
2017-02-16 04:53:40 +00:00
Bruno Cardoso Lopes 17da34d2bd [PCH] Fix a regression when PCH is used with -fmodules
Following up on r291465 after a regression in r276159. When we use
-fmodule-name=X while building a PCH, modular headers in X will be
textually included and the compiler knows that we are not building
module X, so don't serialize such headers in the PCH as being part of a
module, because at this point they are not.

This was causing subtle bugs and malformed AST crashes, for instance,
when using the PCH in subsequent compiler invocation with -fmodules, the
HFI for a modular header would map to the PCH, which would force a
module load of and unexistent module ID.

rdar://problem/30171164

llvm-svn: 294361
2017-02-07 21:54:57 +00:00
Richard Smith 3584515018 P0091R3: Implement basic parsing support for C++17 deduction-guides.
We model deduction-guides as functions with a new kind of name that identifies
the template whose deduction they guide; the bulk of this patch is adding the
new name kind. This gives us a clean way to attach an extensible list of guides
to a class template in a way that doesn't require any special handling in AST
files etc (and we're going to need these functions we come to performing
deduction).

llvm-svn: 294266
2017-02-07 01:37:30 +00:00
David Blaikie 4d92301075 Fix modules codegen to be compatible with modules-ts
The Module::WithCodegen flag was only being set when the module was
parsed from a ModuleMap. Instead set it late, in the ASTWriter to match
the layer where the MODULAR_CODEGEN_DECLs list is determined (the
WithCodegen flag essentially means "are this module's decls in
MODULAR_CODEGEN_DECLs").

When simultaneous emission of AST file and modular object is implemented
this may need to change - the Module::WithCodegen flag will need to be
set earlier, and ideally the MODULAR_CODEGEN_DECLs gathering will
consult this flag (that's not possible right now since Decls destined
for an AST File don't have a Module - only if they're /read/ from a
Module is that true - I expect that would need to change as well).

llvm-svn: 293692
2017-01-31 21:28:19 +00:00
Sam McCall 61e29aafa7 Revert r293585 "Add better ODR checking for modules."
We're seeing what we believe are false positives. (It's hard to tell with the
available diagnostics, and I'm not sure how to reduce them yet).
I'll send Richard reproduction details offline.

djasper/chandlerc suggested this should be a warning for now, to make rolling it
out feasible.

llvm-svn: 293611
2017-01-31 08:24:40 +00:00
Richard Trieu fa3d93a148 Add better ODR checking for modules.
When objects are imported for modules, there is a chance that a name collision
will cause an ODR violation.  Previously, only a small number of such
violations were detected.  This patch provides a stronger check based on
AST nodes.

The information needed to uniquely identify an object is taked from the AST and
put into a one-dimensional byte stream.  This stream is then hashed to give
a value to represent the object, which is stored with the other object data
in the module.

When modules are loaded, and Decl's are merged, the hash values of the two
Decl's are compared.  Only Decl's with matched hash values will be merged.
Mismatch hashes will generate a module error, and if possible, point to the
first difference between the two objects.

The transform from AST to byte stream is a modified depth first algorithm.
Due to references between some AST nodes, a pure depth first algorithm could
generate loops.  For Stmt nodes, a straight depth first processing occurs.
For Type and Decl nodes, they are replaced with an index number and only on
first visit will these nodes be processed.  As an optimization, boolean
values are saved and stored together in reverse order at the end of the
byte stream to lower the ammount of data that needs to be hashed.

Compile time impact was measured at 1.5-2.0% during module building, and
negligible during builds without module building.

Differential Revision: https://reviews.llvm.org/D21675

llvm-svn: 293585
2017-01-31 01:44:15 +00:00
David Blaikie 9ffe5a3525 Prototype of modules codegen
First pass at generating weak definitions of inline functions from module files
(& skipping (-O0) or emitting available_externally (optimizations)
definitions where those modules are used).

External functions defined in modules are emitted into the modular
object file as well (this may turn an existing ODR violation (if that
module were imported into multiple translations) into valid/linkable
code).

Internal symbols (static functions, for example) are not correctly
supported yet. The symbol will be produced, internal, in the modular
object - unreferenceable from the users.

Reviewers: rsmith

Differential Revision: https://reviews.llvm.org/D28845

llvm-svn: 293456
2017-01-30 05:00:26 +00:00
Duncan P. N. Exon Smith 96a06e0ec0 Modules: Return ModuleFile& from ModuleManager::begin, etc.; NFC
Hide the pointer indirection in ModuleManager::begin, ModuleManager::end,
ModuleManager::rbegin, and ModuleManager::rend.  Besides tidying up the call
sites, this is preparation for making ownership of ModuleFile explicit.

llvm-svn: 293394
2017-01-28 22:15:22 +00:00
Richard Smith 600b5261c4 PR0091R3: Implement parsing support for using templates as types.
This change adds a new type node, DeducedTemplateSpecializationType, to
represent a type template name that has been used as a type. This is modeled
around AutoType, and shares a common base class for representing a deduced
placeholder type.

We allow deduced class template types in a few more places than the standard
does: in conditions and for-range-declarators, and in new-type-ids. This is
consistent with GCC and with discussion on the core reflector. This patch
does not yet support deduced class template types being named in typename
specifiers.

llvm-svn: 293207
2017-01-26 20:40:47 +00:00
Richard Smith d230de27f8 Remove and replace DiagStatePoint tracking and lookup data structure.
Rather than storing a single flat list of SourceLocations where the diagnostic
state changes (in source order), we now store a separate list for each FileID
in which there is a diagnostic state transition. (State for other files is
built and cached lazily, on demand.) This has two consequences:

1) We can now sensibly support modules, and properly track the diagnostic state
for modular headers (this matters when, for instance, triggering instantiation
of a template defined within a module triggers diagnostics).

2) It's much faster than the old approach, since we can now just do a binary
search on the offsets within the FileID rather than needing to call
isBeforeInTranslationUnit to determine source order (which is surprisingly
slow). For some pathological (but real world) files, this reduces total
compilation time by more than 10%.

For now, the diagnostic state points for modules are loaded eagerly. It seems
feasible to defer this until diagnostic state information for one of the
module's files is needed, but that's not part of this patch.

llvm-svn: 293123
2017-01-26 01:01:01 +00:00
George Rimar c39f5491a4 [Clang] - Update code to match upcoming llvm::zlib API.
D28684 changed llvm::zlib to return Error instead of Status.
It was accepted and committed in r292214, but then reverted in r292217
because I missed that clang code also needs to be updated.

Patch do that.

D28684 recommitted again as r292226

Differential revision: https://reviews.llvm.org/D28807

llvm-svn: 292227
2017-01-17 15:45:31 +00:00
Malcolm Parsons a3220ce6a3 Tracking exception specification source locations
Summary:
We do not currently track the source locations for exception specifications such
that their source range can be queried through the AST. This leads to trying to
write more complex code to determine the source range for uses like FixItHints
(see D18575 for an example). In addition to use within tools like clang-tidy, I
think this information may become more important to track as exception
specifications become more integrated into the type system.

Patch by Don Hinton.

Reviewers: rsmith

Subscribers: malcolm.parsons, sbarzowski, alexfh, hintonda, cfe-commits

Differential Revision: https://reviews.llvm.org/D20428

llvm-svn: 291771
2017-01-12 16:11:28 +00:00
Manman Ren ffd3e9d766 PCH: fix a regression that reports a module is defined in both pch and pcm.
In r276159, we started to say that a module X is defined in a pch if we specify
-fmodule-name when building the pch. This caused a regression that reports
module X is defined in both pch and pcm if we generate the pch with
-fmodule-name=X and then in a separate clang invocation, we include the pch and
also import X.pcm.

This patch adds an option CompilingPCH similar to CompilingModule. When we use
-fmodule-name=X while building a pch, modular headers in X will be textually
included and the compiler knows that we are not building module X, so we don't
put module X in SUBMODULE_DEFINITION of the pch.

Differential Revision: http://reviews.llvm.org/D28415

llvm-svn: 291465
2017-01-09 19:20:18 +00:00
David Blaikie 95dd362c77 Simplify ASTReader ctor by using in-class initializers for many member variables
llvm-svn: 291155
2017-01-05 18:45:45 +00:00
David Blaikie 61137e1a50 Use shared_ptr instead of IntrusiveRefCntPtr for ModuleFileExtension
The intrusiveness wasn't needed here, so this simplifies/clarifies the
ownership model.

llvm-svn: 291150
2017-01-05 18:23:18 +00:00
David Blaikie b44f0bfb3a Fix for LLVM Bitcode API change (to use std::shared_ptr)
llvm-svn: 291018
2017-01-04 22:36:43 +00:00
Yaxun Liu cc2741ce85 Attempt to fix build failure and regressions due to r290056
Add llvm:: namespace to StringRef.
Make conversion between bool and uint64_t explicit.

llvm-svn: 290058
2016-12-18 06:35:06 +00:00
Yaxun Liu 5b74665a41 Recommit r289979 [OpenCL] Allow disabling types and declarations associated with extensions
Fixed undefined behavior due to cast integer to bool in initializer list.

llvm-svn: 290056
2016-12-18 05:18:55 +00:00
Yaxun Liu 35f6d66b0d Revert r289979 due to regressions
llvm-svn: 289991
2016-12-16 21:23:55 +00:00
Yaxun Liu 2e8331cab6 [OpenCL] Allow disabling types and declarations associated with extensions
Added a map to associate types and declarations with extensions.

Refactored existing diagnostic for disabled types associated with extensions and extended it to declarations for generic situation.

Fixed some bugs for types associated with extensions.

Allow users to use pragma to declare types and functions for supported extensions, e.g.

#pragma OPENCL EXTENSION the_new_extension_name : begin
// declare types and functions associated with the extension here
#pragma OPENCL EXTENSION the_new_extension_name : end

Differential Revision: https://reviews.llvm.org/D21698

llvm-svn: 289979
2016-12-16 19:22:08 +00:00
Richard Smith 30e304e2a6 Remove custom handling of array copies in lambda by-value array capture and
copy constructors of classes with array members, instead using
ArrayInitLoopExpr to represent the initialization loop.

This exposed a bug in the static analyzer where it was unable to differentiate
between zero-initialized and unknown array values, which has also been fixed
here.

llvm-svn: 289618
2016-12-14 00:03:17 +00:00
Joey Gouly e3c85de6df [OpenCL] Refactor read_only/write_only pipes.
This adds the access qualifier to the Pipe Type, rather than using a class
hierarchy. 

It also fixes mergeTypes for Pipes, by disallowing merges. Only identical
pipe types can be merged. The test case in invalid-pipes-cl2.0.cl is added
to check that.

llvm-svn: 288332
2016-12-01 11:30:49 +00:00
Joey Gouly 5788b783ac [OpenCL] Introduce ReadPipeType and WritePipeType.
This allows Sema to diagnose passing a read_only pipe to a
write_only pipe argument.

llvm-svn: 287343
2016-11-18 14:10:54 +00:00
Peter Collingbourne d3a6c70b2d Bitcode: Simplify BitstreamWriter::EnterBlockInfoBlock() interface.
No block info block should need to define local abbreviations, so we can
always use a code width of 2.

Also change all block info block writers to use EnterBlockInfoBlock.

Differential Revision: https://reviews.llvm.org/D26168

llvm-svn: 285660
2016-11-01 01:18:57 +00:00
Mehdi Amini 004b9c7aae Store FileEntry::Filename as a StringRef instead of raw pointer (NFC)
llvm-svn: 283815
2016-10-10 22:52:47 +00:00
Justin Lebar 28f09c50e2 [Sema] Use unique_ptr instead of raw pointers in the late-parsed templates map.
Summary:
This is possible now that MapVector supports move-only values.

Depends on D25404.

Reviewers: timshen

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D25405

llvm-svn: 283766
2016-10-10 16:26:08 +00:00
Justin Lebar 67a78a6cc0 [CUDA] Add #pragma clang force_cuda_host_device_{begin,end} pragmas.
Summary:
These cause us to consider all functions in-between to be __host__
__device__.

You can nest these pragmas; you just can't have more 'end's than
'begin's.

Reviewers: rsmith

Subscribers: tra, jhen, cfe-commits

Differential Revision: https://reviews.llvm.org/D24975

llvm-svn: 283677
2016-10-08 22:15:58 +00:00
Richard Smith c26d97401c [modules] Be sure to emit local specializations of imported templates, even if
the resulting specialization is not referenced by the rest of the AST. This
both avoids performing unnecessary reinstantiations in downstream users of the
AST file and fixes a bug (breaking modules self-host right now) where we would
sometimes fail to emit a definition of a class template specialization if we
imported just a declaration of it from elsewhere (see new testcase for reduced
example).

llvm-svn: 283489
2016-10-06 20:30:51 +00:00
Mehdi Amini 99d1b29503 Use StringRef for MemoryBuffer identifier API (NFC)
llvm-svn: 283043
2016-10-01 16:38:28 +00:00
Richard Smith 96269c59ea P0035R4: add std::align_val_t overloads of operator new/delete in C++17 mode.
llvm-svn: 282800
2016-09-29 22:49:46 +00:00
Manman Ren e6be26c8d4 ObjectiveC generics: Add ObjCTypeParamType in the type system.
We also need to add ObjCTypeParamTypeLoc. ObjCTypeParamType supports the
representation of "T <protocol>" where T is a type parameter. Before this,
we use TypedefType to represent the type parameter for ObjC.

ObjCTypeParamType has "ObjCTypeParamDecl *OTPDecl" and it extends from
ObjCProtocolQualifiers. It is a non-canonical type and is canonicalized
to the underlying type with the protocol qualifiers.

rdar://24619481
rdar://25060179

Differential Revision: http://reviews.llvm.org/D23079

llvm-svn: 281355
2016-09-13 17:25:08 +00:00
Eugene Zelenko e95e7d5d64 Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes.
Differential revision: https://reviews.llvm.org/D24115

llvm-svn: 280870
2016-09-07 21:53:17 +00:00
Richard Smith 0bae624934 Lazily load the ContextDecl for a lambda's DefinitionData, to fix a
deserialization cycle caused by the ContextDecl recursively importing members
of the lambda's closure type.

llvm-svn: 279694
2016-08-25 00:34:00 +00:00
Richard Smith 4b054b2665 PR29097: add an update record when we instantiate the default member
initializer of an imported field.

llvm-svn: 279667
2016-08-24 21:25:37 +00:00
Hubert Tong e4a0c0ec78 Reapply r276069 with workaround for MSVC 2013
llvm-svn: 277286
2016-07-30 22:33:34 +00:00
Vassil Vassilev 19765fb68c [modules] Teach the ASTWriter to ignore mutations coming from the ASTReader.
Processing update records (and loading a module, in general) might trigger
unexpected calls to the ASTWriter (being a mutation listener). Now we have a
mechanism to suppress those calls to the ASTWriter but notify other possible
mutation listeners.

Fixes https://llvm.org/bugs/show_bug.cgi?id=28332

Patch by Cristina Cristescu and me.

Reviewed by Richard Smith (D21800).

llvm-svn: 276473
2016-07-22 21:08:24 +00:00
Richard Smith dc1f042171 [modules] Don't emit initializers for VarDecls within a module eagerly whenever
we first touch any part of that module. Instead, defer them until the first
time that module is (transitively) imported. The initializer step for a module
then recursively initializes modules that its own headers imported.

For example, this avoids running the <iostream> global initializer in programs
that don't actually use iostreams, but do use other parts of the standard
library.

llvm-svn: 276159
2016-07-20 19:10:16 +00:00
Hubert Tong 286547a337 Revert r276069: MSVC bots not happy
llvm-svn: 276074
2016-07-20 01:05:31 +00:00
Hubert Tong 24ee98e4a5 Concepts: Create space for requires-clause in TemplateParameterList; NFC
Summary:
Space for storing the //constraint-expression// of the
//requires-clause// associated with a `TemplateParameterList` is
arranged by taking a bit out of the `NumParams` field for the purpose
of determining whether there is a //requires-clause// or not, and by
adding to the trailing objects tied to the `TemplateParameterList`. An
accessor is provided.

An appropriate argument is supplied to `TemplateParameterList::Create`
at the various call sites.

Serialization changes will addressed as the Concepts implementation
becomes more solid.

Drive-by fix:
This change also replaces the custom
`FixedSizeTemplateParameterListStorage` implementation with one that
follows the interface provided by `llvm::TrailingObjects`.

Reviewers: aaron.ballman, faisalv, rsmith

Subscribers: cfe-commits, nwilson

Differential Revision: https://reviews.llvm.org/D19322

llvm-svn: 276069
2016-07-20 00:30:15 +00:00
Mehdi Amini 9670f847b8 [NFC] Header cleanup
Summary: Removed unused headers, replaced some headers with forward class declarations

Patch by: Eugene <claprix@yandex.ru>

Differential Revision: https://reviews.llvm.org/D20100

llvm-svn: 275882
2016-07-18 19:02:11 +00:00
Argyrios Kyrtzidis d798c05526 [AST] Keep track of the left brace source location of a tag decl.
This is useful for source modification tools. There will be a follow-up commit using it.

llvm-svn: 275590
2016-07-15 18:11:33 +00:00
Eric Fiselier 6ad68551c3 [Feature] Add a builtin for indexing into parameter packs. Patch by Louis Dionne.
This patch adds a __nth_element builtin that allows fetching the n-th type of a
parameter pack with very little compile-time overhead. The patch was inspired by
r252036 and r252115 by David Majnemer, which add a similar __make_integer_seq
builtin for efficiently creating a std::integer_sequence.

Reviewed as D15421. http://reviews.llvm.org/D15421

llvm-svn: 274316
2016-07-01 01:24:09 +00:00
Richard Smith 5179eb7821 P0136R1, DR1573, DR1645, DR1715, DR1736, DR1903, DR1941, DR1959, DR1991:
Replace inheriting constructors implementation with new approach, voted into
C++ last year as a DR against C++11.

Instead of synthesizing a set of derived class constructors for each inherited
base class constructor, we make the constructors of the base class visible to
constructor lookup in the derived class, using the normal rules for
using-declarations.

For constructors, UsingShadowDecl now has a ConstructorUsingShadowDecl derived
class that tracks the requisite additional information. We create shadow
constructors (not found by name lookup) in the derived class to model the
actual initialization, and have a new expression node,
CXXInheritedCtorInitExpr, to model the initialization of a base class from such
a constructor. (This initialization is special because it performs real perfect
forwarding of arguments.)

In cases where argument forwarding is not possible (for inalloca calls,
variadic calls, and calls with callee parameter cleanup), the shadow inheriting
constructor is not emitted and instead we directly emit the initialization code
into the caller of the inherited constructor.

Note that this new model is not perfectly compatible with the old model in some
corner cases. In particular:
 * if B inherits a private constructor from A, and C uses that constructor to
   construct a B, then we previously required that A befriends B and B
   befriends C, but the new rules require A to befriend C directly, and
 * if a derived class has its own constructors (and so its implicit default
   constructor is suppressed), it may still inherit a default constructor from
   a base class

llvm-svn: 274049
2016-06-28 19:03:57 +00:00
Vassil Vassilev cc218abe34 [modules] Allow emission of update records for predefined __va_list_tag.
Handles the cases where old __va_list_tag is coming from a module and the new
is not, needing an update record.

Fixes https://llvm.org/bugs/show_bug.cgi?id=27890

Patch by Cristina Cristescu, Richard Smith and me.

llvm-svn: 273159
2016-06-20 15:10:40 +00:00
Manman Ren 33d8029589 PCH + module: make sure we write out macros associated with builtin identifiers.
When we import a module that defines a builtin identifier from prefix header and
precompile the prefix header, the macro information related to the identifier
is lost.

If we don't precompile the prefix header, the source file can still see the
macro information. The reason is that we write out the identifier in the pch
but not the macro information since the macro is not defined locally.

This is related to r251565. In that commit, if we read a builtin identifier from
a module that wasn't "interesting" to that module, we will still write it out to
a PCH that imports that module.

The fix is to write exported module macros for PCH as well.

rdar://24666630

Differential Revision: http://reviews.llvm.org/D20383

llvm-svn: 271310
2016-05-31 18:19:32 +00:00
Richard Smith 12e7931d0b Add support for derived class special members hiding functions brought in from
a base class via a using-declaration. If a class has a using-declaration
declaring either a constructor or an assignment operator, eagerly declare its
special members in case they need to displace a shadow declaration from a
using-declaration.

llvm-svn: 269398
2016-05-13 06:47:56 +00:00
Dmitry Polukhin d69b505e3c [OpenMP] Parse+Sema for '#pragma omp declare target' syntax version 4.5
Support OpenMP version 4.5 syntax for #pragma omp declare target.

Syntax:
  #pragma omp declare target (extended-list) new-line
or
  #pragma omp declare target clause[ [,] clause ... ] new-line

Where clause is one of the following:
  to(extended-list)
  link(list)

Differential Revision: http://reviews.llvm.org/D20011

llvm-svn: 268925
2016-05-09 14:59:13 +00:00
Manman Ren a0f31a01f3 Method Pool in modules: we make sure that if a module contains an entry for
a selector, the entry should be complete, containing everything introduced by
that module and all modules it imports.

Before writing out the method pool of a module, we sync up the out of date
selectors by pulling in methods for the selectors, from all modules it imports.

In ReadMethodPool, after pulling in the method pool entry for module A, this
lets us skip the modules that module A imports.

rdar://problem/25900131

llvm-svn: 268091
2016-04-29 19:04:05 +00:00
Vassil Vassilev 928c8254a9 Reland r267691 fixing PR27535.
llvm-svn: 267882
2016-04-28 14:13:28 +00:00
Nico Weber 3a94763101 Revert r267691, it caused PR27535.
llvm-svn: 267744
2016-04-27 17:26:08 +00:00
Vassil Vassilev a4d7d783d0 [modules] Fix Decl's Used invariant.
The Decl::isUsed has a value for every decl. In non-module builds it is very
difficult (but possible) to break this invariant but when we walk up the redecl
chain we find the neccessary information.

When deserializing the decls from a module it is much more difficult to update
correctly this invariant. The patch centralizes the information whether a decl
is used in the canonical decl marking the entire entity as being used.

Fixes https://llvm.org/bugs/show_bug.cgi?id=27401

Patch by Cristina Cristescu and me.

Thanks to Richard Smith who helped to debug and understand the issue!

Reviewed by Richard Smith.

llvm-svn: 267691
2016-04-27 10:46:06 +00:00
Richard Smith d49941b726 PR27513: When determining which declaration to put into an exported lookup
table for a module / PCH, never map from a normal declaration of a class to an
injected-class-name declaration (or vice versa). Those declarations live in
distinct lookup tables and should not be confused.

We really shouldn't be using a CXXRecordDecl to represent an
injected-class-name in the first place; I've filed PR27532 so we don't forget.

llvm-svn: 267632
2016-04-26 23:40:43 +00:00
Richard Smith e64e7459aa [modules] Remove some more unnecessary forwarding functions.
llvm-svn: 266687
2016-04-18 21:54:58 +00:00
Richard Smith 72e50fe4ac [modules] Store the location of the lexical update record in a decl update as
an offset from the current record rather than as an absolute bit number. This
gives a minor .pcm file size reduction.

llvm-svn: 266269
2016-04-14 00:50:18 +00:00
Richard Smith 645d2cfd9c [modules] Remove CXX_BASE_SPECIFIERS_OFFSETS table. Instead of storing an ID of
a table entry in the corresponding decl, store an offset from the current
record to the relevant CXX_BASE_SPECIFIERS record. This results in fewer
indirections and a minor .pcm file size reduction.

llvm-svn: 266266
2016-04-14 00:29:55 +00:00
Richard Smith aa165cf759 [modules] Remove CXX_CTOR_INITIALIZERS_OFFSETS table. Instead of storing an ID
of a table entry in the corresponding decl, store an offset from the current
record to the relevant CXX_CTOR_INITIALIZERS record. This results in fewer
indirections and a minor .pcm file size reduction.

llvm-svn: 266254
2016-04-13 21:57:08 +00:00
Richard Smith efc884a466 [modules] Add some missing blockinfo records. No functionality change except to llvm-bcanalyzer output.
llvm-svn: 266176
2016-04-13 07:41:35 +00:00
Richard Smith f1c23dc4c7 [modules] Refactor handling of cases where we write an offset to a prior record into the bitstream and simplify a little, in preparation for doing this in more cases.
llvm-svn: 266160
2016-04-13 02:12:03 +00:00
Richard Smith f144b54a91 Remove unused functions from ASTWriter interface.
llvm-svn: 265857
2016-04-08 21:54:32 +00:00
Vassil Vassilev 71eafded89 [modules] Don't try to add lookup results to non-lookup contexts.
Fixes https://llvm.org/bugs/show_bug.cgi?id=27186

Patch reviewed by Richard Smith.

llvm-svn: 265597
2016-04-06 20:56:03 +00:00
Richard Smith 290d801916 Re-commit r265518 ("[modules] Continue factoring encoding of AST records out of
ASTWriter."), reverted in r265526, with a fix for an iterator invalidation bug
(thanks, MSan!).

llvm-svn: 265564
2016-04-06 17:06:00 +00:00
Dmitry Polukhin 0b0da296e6 [OPENMP] Parsing and Sema support for 'omp declare target' directive
Add parsing, sema analysis for 'declare target' construct for OpenMP 4.0
(4.5 support will be added in separate patch).

The declare target directive specifies that variables, functions (C, C++
and Fortran), and subroutines (Fortran) are mapped to a device. The declare
target directive is a declarative directive. In Clang declare target is
implemented as implicit attribute for the declaration.

The syntax of the declare target directive is as follows:

 #pragma omp declare target
 declarations-definition-seq
 #pragma omp end declare target

Based on patch from Michael Wong http://reviews.llvm.org/D15321

llvm-svn: 265530
2016-04-06 11:38:59 +00:00
Dmitry Polukhin 790b540099 Revert "[modules] Continue factoring encoding of AST records out of ASTWriter."
This reverts commit r265518.

llvm-svn: 265526
2016-04-06 10:01:46 +00:00
Richard Smith 5811c40bb3 [modules] Continue factoring encoding of AST records out of ASTWriter.
llvm-svn: 265518
2016-04-06 06:26:08 +00:00
Richard Smith 69c82bfae7 [modules] Start moving the code for encoding AST records out of ASTWriter into
a separate class. The goal is for this class to have a separate lifetime from
the AST writer so that it can meaningfully track pending statement nodes and
context for more compact encoding of various types.

llvm-svn: 265195
2016-04-01 22:52:03 +00:00
Vassil Vassilev 262f41e91c [modules] Write out identifiers if the ID is local, too.
In some cases a slot for an identifier is requested but it gets written to
another module, causing an assertion.

At the point when we start serializing Rtypes, we have no imported IdentifierID
for float_round_style. We start serializing stuff and allocate an ID for it.
Then, during the serialization process, we pull in the identifier info for it
from TSchemaHelper. Finally, WriteIdentifierTable decides that the identifier
has not changed since it was deserialized, so doesn't emit it.

Fixes https://llvm.org/bugs/show_bug.cgi?id=27041

Discussed on IRC with Richard Smith. Agreed on post commit review if needed.

llvm-svn: 264913
2016-03-30 20:16:03 +00:00
Richard Smith b22a1d186f [modules] When encoding SourceLocations in bitcode, rotate the 'is macro' flag
bit from the top bit to the bottom bit, so that we don't need 6 VBR6 hunks for
each macro location. Reduces libstdc++ module size by about 1%.

llvm-svn: 264540
2016-03-27 20:13:24 +00:00
Richard Smith 34da751484 Remove unused support for replacing declarations from chained AST files.
llvm-svn: 264533
2016-03-27 05:52:25 +00:00
Faisal Vali dc6b596ebb [Cxx1z] Implement Lambda Capture of *this by Value as [=,*this] (P0018R3)
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
2016-03-21 09:25:37 +00:00
Vassil Vassilev 632eac3428 [modules] Fix adding a templated friend functions to a namespace from another module.
When clang adds argument dependent lookup candidates, it can perform template
instantiation. For example, it can instantiate a templated friend function and
register it in the enclosing namespace's lookup table.

Fixes https://llvm.org/bugs/show_bug.cgi?id=24954

Reviewed by Richard Smith.

llvm-svn: 263634
2016-03-16 11:17:04 +00:00
Nico Weber 4293231e50 Serialize `pragma pointers_to_members` state.
Like r262539, but for pointers_to_members.

llvm-svn: 262552
2016-03-03 00:17:35 +00:00
Nico Weber 779355f96b Serialize `pragma ms_struct` state.
pragma ms_struct has an effect on struct decls, and the effect is serialized
correctly already.  But the "is ms_struct currently on" state wasn't before
this change.

This uses the same approach as `pragma clang optimize`: When writing a module,
the state isn't serialized, only when writing a pch file.

llvm-svn: 262539
2016-03-02 23:22:00 +00:00
John McCall 18afab762a Generalize the consumed-parameter array on FunctionProtoType
to allow arbitrary data to be associated with a parameter.

Also, fix a bug where we apparently haven't been serializing
this information for the last N years.

llvm-svn: 262278
2016-03-01 00:49:02 +00:00
Nico Weber 72c57f49c4 Fix rejects-valid caused by r261297.
r261297 called hasUserProvidedDefaultConstructor() to check if defining a
const object is ok.  This is incorrect for this example:

  struct X { template<typename ...T> X(T...); int n; };
  const X x; // formerly OK, now bogus error

Instead, track if a class has a defaulted default constructor, and disallow
a const object for classes that either have defaulted default constructors or
if they need an implicit constructor.

Bug report and fix approach by Richard Smith, thanks!

llvm-svn: 261770
2016-02-24 20:58:14 +00:00
Nico Weber 6a6376b17c Implement the likely resolution of core issue 253.
C++11 requires const objects to have a user-provided constructor, even for
classes without any fields. DR 253 relaxes this to say "If the implicit default
constructor initializes all subobjects, no initializer should be required."

clang is currently the only compiler that implements this C++11 rule, and e.g.
libstdc++ relies on something like DR 253 to compile in newer versions.  This
change  makes it possible to build code that says `const vector<int> v;' again
when using libstdc++5.2 and _GLIBCXX_DEBUG
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60284).

Fixes PR23381.

http://reviews.llvm.org/D16552

llvm-svn: 261297
2016-02-19 01:52:46 +00:00
Richard Smith aada85c5f7 [modules] Compress files embedded into a .pcm file, to reduce the disk usage of -fembed-all-files mode.
llvm-svn: 259976
2016-02-06 02:06:43 +00:00
Richard Smith d79514e24b [modules] Separately track whether an identifier's preprocessor information and
name lookup information have changed since deserialization. For a C++ modules
build, we do not need to re-emit the identifier into the serialized identifier
table if only the name lookup information has changed (and in all cases, we
don't need to re-emit the macro information if only the name lookup information
has changed).

llvm-svn: 259901
2016-02-05 19:03:40 +00:00
Ben Langmuir f5416740fc Fix predefine for __NSConstantString struct type
Per review feedback the name was wrong and it can be used outside
Objective-C.

Unfortunately, making the internal struct visible broke some ASTMatchers
tests that assumed that the first record decl would be from user code,
rather than a builtin type.  I'm worried that this will also affect
users' code.  So this patch adds a typedef to wrap the internal struct
and only makes the typedef visible to namelookup.  This is sufficient to
allow the ASTReader to merge the decls we need without making the struct
itself visible.

rdar://problem/24425801

llvm-svn: 259734
2016-02-04 00:55:24 +00:00
Quentin Colombet 043406b87f Reapply r259624, it is likely not the commit causing the bot failures.
Original message:
Make CF constant string decl visible to name lookup to fix module errors

The return type of the __builtin___*StringMakeConstantString functions
is a pointer to a struct, so we need that struct to be visible to name
lookup so that we will correctly merge multiple declarations of that
type if they come from different modules.

Incidentally, to make this visible to name lookup we need to rename the
type to __NSConstantString, since the real NSConstantString is an
Objective-C interface type.  This shouldn't affect anyone outside the
compiler since users of the constant string builtins cast the result
immediately to CFStringRef.

Since this struct type is otherwise implicitly created by the AST
context and cannot access namelookup, we make this a predefined type
and initialize it in Sema.

Note: this issue of builtins that refer to types not visible to name
lookup technically also affects other builtins (e.g. objc_msgSendSuper),
but in all other cases the builtin is a library builtin and the issue
goes away if you include the library that defines the types it uses,
unlike for these constant string builtins.

rdar://problem/24425801

llvm-svn: 259721
2016-02-03 22:41:00 +00:00
Quentin Colombet 0cdb86bd38 Revert r259624 - Make CF constant string decl visible to name lookup to fix module errors.
This breaks some internal bots in stage2: clang seg fault.
Looking with Ben to see what is going on.

llvm-svn: 259715
2016-02-03 22:14:53 +00:00
Ben Langmuir 6a34e10514 Make CF constant string decl visible to name lookup to fix module errors
The return type of the __builtin___*StringMakeConstantString functions
is a pointer to a struct, so we need that struct to be visible to name
lookup so that we will correctly merge multiple declarations of that
type if they come from different modules.

Incidentally, to make this visible to name lookup we need to rename the
type to __NSConstantString, since the real NSConstantString is an
Objective-C interface type.  This shouldn't affect anyone outside the
compiler since users of the constant string builtins cast the result
immediately to CFStringRef.

Since this struct type is otherwise implicitly created by the AST
context and cannot access namelookup, we make this a predefined type
and initialize it in Sema.

Note: this issue of builtins that refer to types not visible to name
lookup technically also affects other builtins (e.g. objc_msgSendSuper),
but in all other cases the builtin is a library builtin and the issue
goes away if you include the library that defines the types it uses,
unlike for these constant string builtins.

rdar://problem/24425801

llvm-svn: 259624
2016-02-03 03:26:19 +00:00
Xiuli Pan 9c14e28211 [OpenCL] Pipe type support
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
2016-01-09 12:53:17 +00:00
John McCall 32791cc3e1 Only instantiate a default argument once.
By storing the instantiated expression back in the ParmVarDecl,
we remove the last need for separately storing the sub-expression
of a CXXDefaultArgExpr.  This makes PCH/Modules merging quite
simple: CXXDefaultArgExpr records are serialized as references
to the ParmVarDecl, and we ignore redundant attempts to overwrite
the instantiated expression.

This has some extremely marginal impact on user-facing semantics.
However, the major effect is that it avoids IRGen errors about
conflicting definitions due to lambdas in the argument being
instantiated multiple times while sharing the same mangling.
It should also slightly improve memory usage and module file size.

rdar://23810407

llvm-svn: 256983
2016-01-06 22:34:54 +00:00
Samuel Antao ee8fb302f5 [OpenMP] Reapply rL256842: [OpenMP] Offloading descriptor registration and device codegen.
This patch attempts to fix the regressions identified when the patch was committed initially. 

Thanks to Michael Liao for identifying the fix in the offloading metadata generation 
related with side effects in evaluation of function arguments. 
 

llvm-svn: 256933
2016-01-06 13:42:12 +00:00
Samuel Antao 7d5de9a1ee [OpenMP] Revert rL256842: [OpenMP] Offloading descriptor registration and device codegen.
It was causing two regression, so I'm reverting until the cause is found.

llvm-svn: 256858
2016-01-05 19:16:13 +00:00
Samuel Antao 4d5f0bbea1 [OpenMP] Offloading descriptor registration and device codegen.
Summary:
In order to offloading work properly two things need to be in place:
- a descriptor with all the offloading information (device entry functions, and global variable) has to be created by the host and registered in the OpenMP offloading runtime library.
- all the device functions need to be emitted for the device and a convention has to be in place so that the runtime library can easily map the host ID of an entry point with the actual function in the device.

This patch adds support for these two things. However, only entry functions are being registered given that 'declare target' directive is not yet implemented.

About offloading descriptor:

The details of the descriptor are explained with more detail in http://goo.gl/L1rnKJ. Basically the descriptor will have fields that specify the number of devices, the pointers to where the device images begin and end (that will be defined by the linker), and also pointers to a the begin and end of table whose entries contain information about a specific entry point. Each entry has the type:
```
struct __tgt_offload_entry{
 void *addr;
 char *name;
 int64_t size;
};
```  
and will be implemented in a pre determined (ELF) section `.omp_offloading.entries` with 1-byte alignment, so that when all the objects are linked, the table is in that section with no padding in between entries (will be like a C array). The code generation ensures that all `__tgt_offload_entry` entries are emitted in the same order for both host and device so that the runtime can have the corresponding entries in both host and device in same index of the table, and efficiently implement the mapping.

The resulting descriptor is registered/unregistered with the runtime library using the calls `__tgt_register_lib` and `__tgt_unregister_lib`. The registration is implemented in a high priority global initializer so that the registration happens always before any initializer (that can potentially include target regions) is run.

The driver flag -omptargets= was created to specify a comma separated list of devices the user wants to support so that the new functionality can be exercised. Each device is specified with its triple.


About target codegen:

The target codegen is pretty much straightforward as it reuses completely the logic of the host version for the same target region. The tricky part is to identify the meaningful target regions in the device side. Unlike other programming models, like CUDA, there are no already outlined functions with attributes that mark what should be emitted or not. So, the information on what to emit is passed in the form of metadata in host bc file. This requires a new option to pass the host bc to the device frontend. Then everything is similar to what happens in CUDA: the global declarations emission is intercepted to check to see if it is an "interesting" declaration. The difference is that instead of checking an attribute, the metadata information in checked. Right now, there is only a form of metadata to pass information about the device entry points (target regions). A class `OffloadEntriesInfoManagerTy` was created to manage all the information and queries related with the metadata. The metadata looks like this:
```
!omp_offload.info = !{!0, !1, !2, !3, !4, !5, !6}

!0 = !{i32 0, i32 52, i32 77426347, !"_ZN2S12r1Ei", i32 479, i32 13, i32 4}
!1 = !{i32 0, i32 52, i32 77426347, !"_ZL7fstatici", i32 461, i32 11, i32 5}
!2 = !{i32 0, i32 52, i32 77426347, !"_Z9ftemplateIiET_i", i32 444, i32 11, i32 6}
!3 = !{i32 0, i32 52, i32 77426347, !"_Z3fooi", i32 99, i32 11, i32 0}
!4 = !{i32 0, i32 52, i32 77426347, !"_Z3fooi", i32 272, i32 11, i32 3}
!5 = !{i32 0, i32 52, i32 77426347, !"_Z3fooi", i32 127, i32 11, i32 1}
!6 = !{i32 0, i32 52, i32 77426347, !"_Z3fooi", i32 159, i32 11, i32 2}
```
The fields in each metadata entry are (in sequence):
Entry 1) an ID of the type of metadata - right now only zero is used meaning "OpenMP target region".
Entry 2) a unique ID of the device where the input source file that contain the target region lives. 
Entry 3) a unique ID of the file where the input source file that contain the target region lives. 
Entry 4) a mangled name of the function that encloses the target region.
Entries 5) and 6) line and column number where the target region was found.
Entry 7) is the order the entry was emitted.

Entry 2) and 3) are required to distinguish files that have the same function name.
Entry 4) is required to distinguish different instances of the same declaration (usually templated ones)
Entries 5) and 6) are required to distinguish the particular target region in body of the function (it is possible that a given target region is not an entry point - if clause can evaluate always to zero - and therefore we need to identify the "interesting" target regions. )

This patch replaces http://reviews.llvm.org/D12306.

Reviewers: ABataev, hfinkel, tra, rjmccall, sfantao

Subscribers: FBrygidyn, piotr.rak, Hahnfeld, cfe-commits

Differential Revision: http://reviews.llvm.org/D12614

llvm-svn: 256842
2016-01-05 16:23:04 +00:00
Douglas Gregor 8f64ca1529 Module file extensions: pass a Sema through to the extension writer.
Module file extensions are likely to need access to
Sema/Preprocessor/ASTContext, and cannot get it through other
sources.

llvm-svn: 255065
2015-12-08 22:43:32 +00:00
Eugene Zelenko ddaa4b4990 Use range loops and autos in lib/Serialization/ASTWriter.cpp.
Differential revision: http://reviews.llvm.org/D15311

llvm-svn: 255033
2015-12-08 18:00:11 +00:00
Richard Smith a8cfffa351 [modules] Refactor handling of -fmodules-embed-*. Track this properly rather
than reusing the "overridden buffer" mechanism. This will allow us to make
embedded files and overridden files behave differently in future.

llvm-svn: 254121
2015-11-26 02:04:16 +00:00