Commit Graph

24 Commits

Author SHA1 Message Date
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Lang Hames 52a34a78d9 [ORC] Refactor definition-generation, add a generator for static libraries.
This patch replaces the JITDylib::DefinitionGenerator typedef with a class of
the same name, and adds support for attaching a sequence of DefinitionGeneration
objects to a JITDylib.

This patch also adds a new definition generator,
StaticLibraryDefinitionGenerator, that can be used to add symbols fom a static
library to a JITDylib. An object from the static library will be added (via
a supplied ObjectLayer reference) whenever a symbol from that object is
referenced.

To enable testing, lli is updated to add support for the --extra-archive option
when running in -jit-kind=orc-lazy mode.

llvm-svn: 368707
2019-08-13 16:05:18 +00:00
Lang Hames d4a8089f03 [ORC] Update symbol lookup to use a single callback with a required symbol state
rather than two callbacks.

The asynchronous lookup API (which the synchronous lookup API wraps for
convenience) used to take two callbacks: OnResolved (called once all requested
symbols had an address assigned) and OnReady to be called once all requested
symbols were safe to access). This patch updates the asynchronous lookup API to
take a single 'OnComplete' callback and a required state (SymbolState) to
determine when the callback should be made. This simplifies the common use case
(where the client is interested in a specific state) and will generalize neatly
as new states are introduced to track runtime initialization of symbols.

Clients who were making use of both callbacks in a single query will now need to
issue two queries (one for SymbolState::Resolved and another for
SymbolState::Ready). Synchronous lookup API clients who were explicitly passing
the WaitOnReady argument will now need neeed to pass a SymbolState instead (for
'WaitOnReady == true' use SymbolState::Ready, for 'WaitOnReady == false' use
SymbolState::Resolved). Synchronous lookup API clients who were using default
arugment values should see no change.

llvm-svn: 362832
2019-06-07 19:33:51 +00:00
Lang Hames 0dcf69eb82 [ORC] Remove some unreachable code.
Fixes http://llvm.org/PR41662.

llvm-svn: 361199
2019-05-20 21:30:33 +00:00
Lang Hames b12867230c [ORC] Allow JITDylib definition generators to return Errors.
Background: A definition generator can be attached to a JITDylib to generate
new definitions in response to queries. For example: a generator that forwards
calls to dlsym can map symbols from a dynamic library into the JIT process on
demand.

If definition generation fails then the generator should be able to return an
error. This allows the JIT API to distinguish between the case where a
generator does not provide a definition, and the case where it was not able to
determine whether it provided a definition due to an error.

The immediate motivation for this is cross-process symbol lookups: If the
remote-lookup generator is attached to a JITDylib early in the search list, and
if a generator failure is misinterpreted as "no definition in this JITDylib" then
lookup may continue and bind to a different definition in a later JITDylib, which
is a bug.

llvm-svn: 359521
2019-04-30 00:03:26 +00:00
Lang Hames 11c8dfa583 Initial implementation of JITLink - A replacement for RuntimeDyld.
Summary:

JITLink is a jit-linker that performs the same high-level task as RuntimeDyld:
it parses relocatable object files and makes their contents runnable in a target
process.

JITLink aims to improve on RuntimeDyld in several ways:

(1) A clear design intended to maximize code-sharing while minimizing coupling.

RuntimeDyld has been developed in an ad-hoc fashion for a number of years and
this had led to intermingling of code for multiple architectures (e.g. in
RuntimeDyldELF::processRelocationRef) in a way that makes the code more
difficult to read, reason about, extend. JITLink is designed to isolate
format and architecture specific code, while still sharing generic code.

(2) Support for native code models.

RuntimeDyld required the use of large code models (where calls to external
functions are made indirectly via registers) for many of platforms due to its
restrictive model for stub generation (one "stub" per symbol). JITLink allows
arbitrary mutation of the atom graph, allowing both GOT and PLT atoms to be
added naturally.

(3) Native support for asynchronous linking.

JITLink uses asynchronous calls for symbol resolution and finalization: these
callbacks are passed a continuation function that they must call to complete the
linker's work. This allows for cleaner interoperation with the new concurrent
ORC JIT APIs, while still being easily implementable in synchronous style if
asynchrony is not needed.

To maximise sharing, the design has a hierarchy of common code:

(1) Generic atom-graph data structure and algorithms (e.g. dead stripping and
 |  memory allocation) that are intended to be shared by all architectures.
 |
 + -- (2) Shared per-format code that utilizes (1), e.g. Generic MachO to
       |  atom-graph parsing.
       |
       + -- (3) Architecture specific code that uses (1) and (2). E.g.
                JITLinkerMachO_x86_64, which adds x86-64 specific relocation
                support to (2) to build and patch up the atom graph.

To support asynchronous symbol resolution and finalization, the callbacks for
these operations take continuations as arguments:

  using JITLinkAsyncLookupContinuation =
      std::function<void(Expected<AsyncLookupResult> LR)>;

  using JITLinkAsyncLookupFunction =
      std::function<void(const DenseSet<StringRef> &Symbols,
                         JITLinkAsyncLookupContinuation LookupContinuation)>;

  using FinalizeContinuation = std::function<void(Error)>;

  virtual void finalizeAsync(FinalizeContinuation OnFinalize);

In addition to its headline features, JITLink also makes other improvements:

  - Dead stripping support: symbols that are not used (e.g. redundant ODR
    definitions) are discarded, and take up no memory in the target process
    (In contrast, RuntimeDyld supported pointer equality for weak definitions,
    but the redundant definitions stayed resident in memory).

  - Improved exception handling support. JITLink provides a much more extensive
    eh-frame parser than RuntimeDyld, and is able to correctly fix up many
    eh-frame sections that RuntimeDyld currently (silently) fails on.

  - More extensive validation and error handling throughout.

This initial patch supports linking MachO/x86-64 only. Work on support for
other architectures and formats will happen in-tree.

Differential Revision: https://reviews.llvm.org/D58704

llvm-svn: 358818
2019-04-20 17:10:34 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Matthias Braun 9fd397b423 ADT/STLExtras: Introduce llvm::empty; NFC
This is modeled after C++17 std::empty().

Differential Revision: https://reviews.llvm.org/D53909

llvm-svn: 345679
2018-10-31 00:23:23 +00:00
Lang Hames 23cb2e7f77 [ORC] Re-apply r345077 with fixes to remove ambiguity in lookup calls.
llvm-svn: 345098
2018-10-23 23:01:39 +00:00
Reid Kleckner db367e952e Revert r345077 "[ORC] Change how non-exported symbols are matched during lookup."
Doesn't build on Windows. The call to 'lookup' is ambiguous. Clang and
MSVC agree, anyway.

http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/787
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\unittests\ExecutionEngine\Orc\CoreAPIsTest.cpp(315): error C2668: 'llvm::orc::ExecutionSession::lookup': ambiguous call to overloaded function
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\include\llvm/ExecutionEngine/Orc/Core.h(823): note: could be 'llvm::Expected<llvm::JITEvaluatedSymbol> llvm::orc::ExecutionSession::lookup(llvm::ArrayRef<llvm::orc::JITDylib *>,llvm::orc::SymbolStringPtr)'
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\include\llvm/ExecutionEngine/Orc/Core.h(817): note: or       'llvm::Expected<llvm::JITEvaluatedSymbol> llvm::orc::ExecutionSession::lookup(const llvm::orc::JITDylibSearchList &,llvm::orc::SymbolStringPtr)'
C:\b\slave\clang-x64-windows-msvc\build\llvm.src\unittests\ExecutionEngine\Orc\CoreAPIsTest.cpp(315): note: while trying to match the argument list '(initializer list, llvm::orc::SymbolStringPtr)'

llvm-svn: 345078
2018-10-23 20:54:43 +00:00
Lang Hames 841796decd [ORC] Change how non-exported symbols are matched during lookup.
In the new scheme the client passes a list of (JITDylib&, bool) pairs, rather
than a list of JITDylibs. For each JITDylib the boolean indicates whether or not
to match against non-exported symbols (true means that they should be found,
false means that they should not). The MatchNonExportedInJD and MatchNonExported
parameters on lookup are removed.

The new scheme is more flexible, and easier to understand.

This patch also updates JITDylib search orders to be lists of (JITDylib&, bool)
pairs to match the new lookup scheme. Error handling is also plumbed through
the LLJIT class to allow regression tests to fail predictably when a lookup from
a lazy call-through fails.

llvm-svn: 345077
2018-10-23 20:20:22 +00:00
Lang Hames 079df9ab2c [ORC] Rename ORC layers to make the "new" ORC layers the default.
This commit adds a 'Legacy' prefix to old ORC layers and utilities, and removes
the '2' suffix from the new ORC layers. If you wish to continue using the old
ORC layers you will need to add a 'Legacy' prefix to your classes. If you were
already using the new ORC layers you will need to drop the '2' suffix.

The legacy layers will remain in-tree until the new layers reach feature
parity with them. This will involve adding support for removing code from the
new layers, and ensuring that performance is comperable.

llvm-svn: 344572
2018-10-15 22:56:10 +00:00
Lang Hames 6e66b2a6a3 [ORC] Switch to DenseMap/DenseSet for ORC symbol map/set types.
llvm-svn: 344565
2018-10-15 22:27:02 +00:00
Lang Hames a5157d6f4b [ORC] Simplify naming for JITDylib definition generators.
Renames:
  JITDylib's setFallbackDefinitionGenerator method to setGenerator.
  DynamicLibraryFallbackGenerator class to DynamicLibrarySearchGenerator.
  ReexportsFallbackDefinitionGenerator to ReexportsGenerator.

llvm-svn: 344489
2018-10-15 05:07:54 +00:00
Lang Hames 7899ccbcca [ORC] During lookup, do not match against hidden symbols in other JITDylibs.
This adds two arguments to the main ExecutionSession::lookup method:
MatchNonExportedInJD, and MatchNonExported. These control whether and where
hidden symbols should be matched when searching a list of JITDylibs.

A similar effect could have been achieved by filtering search results, but
this would have involved materializing symbol definitions (since materialization
is triggered on lookup) only to throw the results away, among other issues.

llvm-svn: 344467
2018-10-13 21:53:40 +00:00
Lang Hames bf6603e918 [ORC] Promote and rename private symbols inside the CompileOnDemand layer,
rather than require them to have been promoted before being passed in.

Dropping this precondition is better for layer composition (CompileOnDemandLayer
was the only one that placed pre-conditions on the modules that could be added).
It also means that the promoted private symbols do not show up in the target
JITDylib's symbol table. Instead, they are confined to the hidden implementation
dylib that contains the actual definitions.

For the 403.gcc testcase this cut down the public symbol table size from ~15,000
symbols to ~4000, substantially reducing symbol dependence tracking costs.

llvm-svn: 344078
2018-10-09 20:44:32 +00:00
Lang Hames 47d0a37704 [ORC] Add convenience methods for creating DynamicLibraryFallbackGenerators for
libraries on disk, and for the current process.

Avoids more boilerplate during JIT construction.

llvm-svn: 343430
2018-10-01 00:59:28 +00:00
Lang Hames d435ce4343 [ORC] Extract and tidy up JITTargetMachineBuilder, add unit test.
(1) Adds comments for the API.

(2) Removes the setArch method: This is redundant: the setArchStr method on the
    triple should be used instead.

(3) Turns EmulatedTLS on by default. This matches EngineBuilder's behavior.

llvm-svn: 343423
2018-09-30 19:12:23 +00:00
Lang Hames d5f56c5979 [ORC] Rename VSO to JITDylib.
VSO was a little close to VDSO (an acronym on Linux for Virtual Dynamic Shared
Object) for comfort. It also risks giving the impression that instances of this
class could be shared between ExecutionSessions, which they can not.

JITDylib seems moderately less confusing, while still hinting at how this
class is intended to be used, i.e. as a JIT-compiled stand-in for a dynamic
library (code that would have been a dynamic library if you had wanted to
compile it ahead of time).

llvm-svn: 340084
2018-08-17 21:18:18 +00:00
Lang Hames 2f17824463 [ORC] Don't call isa<> on a null value.
This should fix the recent builder failures in the test-global-ctors.ll testcase.

llvm-svn: 335680
2018-06-26 22:43:01 +00:00
Lang Hames 8f9dbb1d64 [ORC] Fix a missing return value.
llvm-svn: 335677
2018-06-26 22:30:42 +00:00
Lang Hames 6a94134b11 [ORC] Add LLJIT and LLLazyJIT, and replace OrcLazyJIT in LLI with LLLazyJIT.
LLJIT is a prefabricated ORC based JIT class that is meant to be the go-to
replacement for MCJIT. Unlike OrcMCJITReplacement (which will continue to be
supported) it is not API or bug-for-bug compatible, but targets the same
use cases: Simple, non-lazy compilation and execution of LLVM IR.

LLLazyJIT extends LLJIT with support for function-at-a-time lazy compilation,
similar to what was provided by LLVM's original (now long deprecated) JIT APIs.

This commit also contains some simple utility classes (CtorDtorRunner2,
LocalCXXRuntimeOverrides2, JITTargetMachineBuilder) to support LLJIT and
LLLazyJIT.

Both of these classes are works in progress. Feedback from JIT clients is very
welcome!

llvm-svn: 335670
2018-06-26 21:35:48 +00:00
Lang Hames 5721ee48a2 [ORC] Re-apply r327566 with a fix for test-global-ctors.ll.
Also clang-formats the patch, which I should have done the first time around.

llvm-svn: 327594
2018-03-15 00:30:14 +00:00
Lang Hames b1cd98a18d [Orc] Add support classes for inspecting and running C++ static ctor/dtors, and
use these to add support for C++ static ctors/dtors to the Orc-lazy JIT in LLI.

Replace the trivial_retval_1 regression test - the new 'hello' test is covering
strictly more code. 

llvm-svn: 233885
2015-04-02 04:34:45 +00:00