Commit Graph

174 Commits

Author SHA1 Message Date
Aart Bik
0b1764a3d7 [mlir][sparse] sparse tensor storage implementation
This revision connects the generated sparse code with an actual
sparse storage scheme, which can be initialized from a test file.
Lacking a first-class citizen SparseTensor type (with buffer),
the storage is hidden behind an opaque pointer with some "glue"
to bring the pointer back to tensor land. Rather than generating
sparse setup code for each different annotated tensor (viz. the
"pack" methods in TACO), a single "one-size-fits-all" implementation
has been added to the runtime support library.  Many details and
abstractions need to be refined in the future, but this revision
allows full end-to-end integration testing and performance
benchmarking (with on one end, an annotated Lingalg
op and, on the other end, a JIT/AOT executable).

Reviewed By: nicolasvasilache, bixia

Differential Revision: https://reviews.llvm.org/D95847
2021-02-10 11:57:24 -08:00
Alex Zinenko
2996a8d675 [mlir] avoid exposing mutable DialectRegistry from MLIRContext
MLIRContext allows its users to access directly to the DialectRegistry it
contains. While sometimes useful for registering additional dialects on an
already existing context, this breaks the encapsulation by essentially giving
raw accesses to a part of the context's internal state. Remove this mutable
access and instead provide a method to append a given DialectRegistry to the
one already contained in the context. Also provide a shortcut mechanism to
construct a context from an already existing registry, which seems to be a
common use case in the wild. Keep read-only access to the registry contained in
the context in case it needs to be copied or used for constructing another
context.

With this change, DialectRegistry is no longer concerned with loading the
dialects and deciding whether to invoke delayed interface registration. Loading
is concentrated in the MLIRContext, and the functionality of the registry
better reflects its name.

Depends On D96137

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D96331
2021-02-10 12:07:34 +01:00
Tobias Gysi
dd719fda76 Revert "[mlir] add support for verification in integration tests"
This reverts commit 5fa893c.
Windows build bot fails due to missing header
https://reviews.llvm.org/D96326
2021-02-09 19:16:02 +01:00
Tobias Gysi
5fa893cc38 [mlir] add support for verification in integration tests
The patch extends the runner utils by verification methods that compare two memrefs. The methods compare the content of the two memrefs and print success if the data is identical up to a small numerical error. The methods are meant to simplify the development of integration tests that for example compare optimized and unoptimized code paths (cf. the updates to the linalg matmul integration tests).

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D96326
2021-02-09 17:43:11 +01:00
Mehdi Amini
d6efb6fc86 Rework ExecutionEngine::invoke() to make it more friendly to use from C++
This new invoke will pack a list of argument before calling the
`invokePacked` method. It accepts returned value as output argument
wrapped in `ExecutionEngine::Result<T>`, and delegate the packing of
arguments to a trait to allow for customization for some types.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D95961
2021-02-06 01:32:50 +00:00
Matthew Parkinson
dd2dac2fd0 Fix MLIR Async Runtime DLL on Windows
The AsyncRuntime declares prototypes for extern "C" functions inside a
namespace in the header, but not inside that namespace in the
definition. This causes Visual Studio to treat them as different
entities and thus the dllexport is ignored for the definitions.

Using the same namespace fixes this issue.

Secondly, this commit moves the dllexport to be consistent with the
JITs expectation.

This is an update to https://reviews.llvm.org/D95386 that fixes the
compile issues in old versions of Visual studio.

Differential Revision: https://reviews.llvm.org/D95933
2021-02-03 12:23:41 +00:00
Mehdi Amini
29fffff8d3 Revert "Fix namespace for MLIR Async Runtime"
This reverts commit b7d80058ff.

The mlir-windows buildbot is broken.
2021-02-02 20:54:16 +00:00
Matthew Parkinson
b7d80058ff Fix namespace for MLIR Async Runtime
The MLIR Async runtime uses different namespacing for the header file,
and the definitions of its C API. The header file places the extern "C"
functions inside namespace mlir::runtime, and the definitions are not
in a namespace. This causes issues in cl.exe. It treats the declaration
and definition as different, and thus does not apply dllexport to the
definition, which leads to the mlir_async_runtime.dll containing no
definitions, and the mlir_async_runtime.lib not being generated.

This patch moves the namespace to cover the definitions, and thus
generates the dll correctly on Windows with cl.exe.

This was tested with Visual Studio C++ 19.28.29336.

Differential Revision: https://reviews.llvm.org/D95386
2021-02-02 19:17:41 +00:00
Christian Sigg
27924b1263 [mlir] Remove mlir_c_runner_utils_static.
The library is not actually static when BUILD_SHARED_LIBS is on, and tests need to explicitly load it already. Also, the shared objects it was linked to did not use any symbols from it and it was therefore never linked to it.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D95612
2021-01-29 15:04:48 +01:00
Nicolas Vasilache
9cbef8c905 [mlir] Fix integration tests 2021-01-28 16:54:50 +00:00
Eugene Zhulenev
f63f28ed54 [mlir:async] Fix deadlock in async runtime await-and-execute functions
`emplace???` functions running concurrently can set the ready flag and then pending awaiter will never be executed

Differential Revision: https://reviews.llvm.org/D95517
2021-01-27 05:08:53 -08:00
Christian Sigg
bd3a387ee7 Revert [mlir] Link mlir_runner_utils statically into cuda/rocm-runtime-wrappers (cf50f4f764)
There are cmake failures that I do not know how to fix.

Differential Revision: https://reviews.llvm.org/D95162
2021-01-21 22:38:59 +01:00
Aart Bik
5959c28f24 [mlir][sparse] add asserts on reading in tensor data
Rationale:
Since I made the argument that metadata helps with extra
verification checks, I better actually do that ;-)

Reviewed By: penpornk

Differential Revision: https://reviews.llvm.org/D95072
2021-01-20 14:30:13 -08:00
Eugene Zhulenev
a2223b09b1 [mlir:async] Fix data races in AsyncRuntime
Resumed coroutine potentially can deallocate the token/value/group and destroy the mutex before the std::unique_ptr destructor.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D95037
2021-01-20 13:23:39 -08:00
Christian Sigg
cf50f4f764 [mlir] Link mlir_runner_utils statically into cuda/rocm-runtime-wrappers.
The runtime-wrappers depend on LLVMSupport, pulling in static initialization code (e.g. command line arguments). Dynamically loading multiple such libraries results in ODR violoations.

So far this has not been an issue, but in D94421, I would like to load both the async-runtime and the cuda-runtime-wrappers as part of a cuda-runner integration test. When doing this, code that asserts that an option category is only registered once fails (note that I've only experienced this in Google's bazel where the async-runtime depends on LLVMSupport, but a similar issue would happen in cmake if more than one runtime-wrapper starts to depend on LLVMSupport).

The underlying issue is that we have a mix of static and dynamic linking. If all dependencies were loaded as shared objects (i.e. if LLVMSupport was linked dynamically to the runtime wrappers), each dependency would only get loaded once. However, linking dependencies dynamically would require special attention to paths (one could dynamically load the dependencies first given explicit paths). The simpler approach seems to be to link all dependencies statically into a single shared object.

This change basically applies the same logic that we have in the c_runner_utils: we have a shared object target that can be loaded dynamically, and we have a static library target that can be linked to other runtime-wrapper shared object targets.

Reviewed By: herhut

Differential Revision: https://reviews.llvm.org/D94399
2021-01-20 12:10:16 +01:00
Mehdi Amini
7dadcd02d6 Fix a few GCC compiler warnings (NFC) 2021-01-19 06:00:04 +00:00
Aart Bik
d8fc27301d [mlir][sparse] improved sparse runtime support library
Added the ability to read (an extended version of) the FROSTT
file format, so that we can now read in sparse tensors of arbitrary
rank. Generalized the API to deal with more than two dimensions.

Also added the ability to sort the indices of sparse tensors
lexicographically. This is an important step towards supporting
auto gen of initialization code, since sparse storage formats
are easier to initialize if the indices are sorted. Since most
external formats don't enforce such properties, it is convenient
to have this ability in our runtime support library.

Lastly, the re-entrant problem of the original implementation
is fixed by passing an opaque object around (rather than having
a single static variable, ugh!).

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D94852
2021-01-16 12:16:10 -08:00
Eugene Zhulenev
bb0e621387 [mlir] AsyncRuntime: use LLVM ThreadPool to run async tasks
Revert https://reviews.llvm.org/D92368 after the dynamic library unloading was fixed in https://reviews.llvm.org/D94312

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D94346
2021-01-09 02:39:52 -08:00
Eugene Zhulenev
78b3bce23b [mlir] AsyncRuntime: disable mlir-runner init/disable for WIN32
Differential Revision: https://reviews.llvm.org/D94339
2021-01-08 14:03:25 -08:00
Eugene Zhulenev
1fc986427b [mlir:JitRunner] Use custom shared library init/destroy functions if available
Use custom mlir runner init/destroy functions to safely init and destroy shared libraries loaded by the JitRunner.

This mechanism is ignored for Windows builds (for now) because init/destroy functions are not exported, and library unloading relies on static destructors.

Re-submit https://reviews.llvm.org/D94270 with a temporary workaround for windows

Differential Revision: https://reviews.llvm.org/D94312
2021-01-08 13:16:08 -08:00
Alex Zinenko
dd5165a920 [mlir] replace LLVM dialect float types with built-ins
Continue the convergence between LLVM dialect and built-in types by replacing
the bfloat, half, float and double LLVM dialect types with their built-in
counterparts. At the API level, this is a direct replacement. At the syntax
level, we change the keywords to `bf16`, `f16`, `f32` and `f64`, respectively,
to be compatible with the built-in type syntax. The old keywords can still be
parsed but produce a deprecation warning and will be eventually removed.

Depends On D94178

Reviewed By: mehdi_amini, silvas, antiagainst

Differential Revision: https://reviews.llvm.org/D94179
2021-01-08 17:38:12 +01:00
Eugene Zhulenev
740950cf1c Revert "[mlir:JitRunner] Use custom shared library init/destroy functions if available"
This reverts commit 84dc9b451b.

Fix Windows breakage: http://lab.llvm.org:8011/#/builders/13/builds/3658/steps/6/logs/stdio

Differential Revision: https://reviews.llvm.org/D94309
2021-01-08 07:46:35 -08:00
Eugene Zhulenev
84dc9b451b [mlir:JitRunner] Use custom shared library init/destroy functions if available
Use custom mlir runner init/destroy functions to safely init and destroy shared libraries loaded by the JitRunner.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D94270
2021-01-08 07:14:21 -08:00
Alex Zinenko
2230bf99c7 [mlir] replace LLVMIntegerType with built-in integer type
The LLVM dialect type system has been closed until now, i.e. did not support
types from other dialects inside containers. While this has had obvious
benefits of deriving from a common base class, it has led to some simple types
being almost identical with the built-in types, namely integer and floating
point types. This in turn has led to a lot of larger-scale complexity: simple
types must still be converted, numerous operations that correspond to LLVM IR
intrinsics are replicated to produce versions operating on either LLVM dialect
or built-in types leading to quasi-duplicate dialects, lowering to the LLVM
dialect is essentially required to be one-shot because of type conversion, etc.
In this light, it is reasonable to trade off some local complexity in the
internal implementation of LLVM dialect types for removing larger-scale system
complexity. Previous commits to the LLVM dialect type system have adapted the
API to support types from other dialects.

Replace LLVMIntegerType with the built-in IntegerType plus additional checks
that such types are signless (these are isolated in a utility function that
replaced `isa<LLVMType>` and in the parser). Temporarily keep the possibility
to parse `!llvm.i32` as a synonym for `i32`, but add a deprecation notice.

Reviewed By: mehdi_amini, silvas, antiagainst

Differential Revision: https://reviews.llvm.org/D94178
2021-01-07 19:48:31 +01:00
Eugene Zhulenev
621ad468d9 [mlir] Async: lowering async.value to LLVM
1. Add new methods to Async runtime API to support yielding async values
2. Add lowering from `async.yield` with value payload to the new runtime API calls

`async.value` lowering requires that payload type is convertible to LLVM and supported by `llvm.mlir.cast` (DialectCast) operation.

Reviewed By: csigg

Differential Revision: https://reviews.llvm.org/D93592
2020-12-25 02:23:48 -08:00
Alex Zinenko
8de43b926f [mlir] Remove instance methods from LLVMType
LLVMType contains multiple instance methods that were introduced initially for
compatibility with LLVM API. These methods boil down to `cast` followed by
type-specific call. Arguably, they are mostly used in an LLVM cast-follows-isa
anti-pattern. This doesn't connect nicely to the rest of the MLIR
infrastructure and actively prevents it from making the LLVM dialect type
system more open, e.g., reusing built-in types when appropriate. Remove such
instance methods and replaces their uses with apporpriate casts and methods on
derived classes. In some cases, the result may look slightly more verbose, but
most cases should actually use a stricter subtype of LLVMType anyway and avoid
the isa/cast.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D93680
2020-12-22 23:34:54 +01:00
Eugene Zhulenev
11f1027b4d [mlir] AsyncRuntime: mode runtime declarations to mlir::runtime namespace
Define Async runtime related typedefs in the `mlir::runtime` namespace.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D93391
2020-12-16 11:05:21 -08:00
River Riddle
09f7a55fad [mlir][Types][NFC] Move all of the builtin Type classes to BuiltinTypes.h
This is part of a larger refactoring the better congregates the builtin structures under the BuiltinDialect. This also removes the problematic "standard" naming that clashes with the "standard" dialect, which is not defined within IR/. A temporary forward is placed in StandardTypes.h to allow time for downstream users to replaced references.

Differential Revision: https://reviews.llvm.org/D92435
2020-12-03 18:02:10 -08:00
Eugene Zhulenev
9edcedf7f2 [mlir] AsyncRuntime: disable threading until test flakiness is fixed
ExecutionEngine/LLJIT do not run globals destructors in loaded dynamic libraries when destroyed, and threads managed by ThreadPool can race with program termination, and it leads to segfaults.

TODO: Re-enable threading after fixing a problem with destructors, or removing static globals from dynamic library.

Differential Revision: https://reviews.llvm.org/D92368
2020-12-01 01:12:16 -08:00
Eugene Zhulenev
3d95d1b477 [mlir] AsyncRuntime: fix concurrency bugs + fix exports in methods definitions
1. Move ThreadPool ownership to the runtime, and wait for the async tasks completion in the destructor.
2. Remove MLIR_ASYNCRUNTIME_EXPORT from method definitions because they are unnecessary in .cpp files, as only function declarations need to be exported, not their definitions.
3. Fix concurrency bugs in group emplace and potential use-after-free in token emplace.

Tested internally 10k runs in `async.mlir` and `async-group.mlir`.

Fixed: https://bugs.llvm.org/show_bug.cgi?id=48267

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D91988
2020-11-24 03:53:13 -08:00
Alexander Belyaev
c6b2c17e9c [mlir] Add a print function for memref<*xi64>.
Differential Revision: https://reviews.llvm.org/D91070
2020-11-23 16:17:41 +01:00
Ella Ma
1756d67934 [llvm][clang][mlir] Add checks for the return values from Target::createXXX to prevent protential null deref
All these potential null pointer dereferences are reported by my static analyzer for null smart pointer dereferences, which has a different implementation from `alpha.cplusplus.SmartPtr`.

The checked pointers in this patch are initialized by Target::createXXX functions. When the creator function pointer is not correctly set, a null pointer will be returned, or the creator function may originally return a null pointer.

Some of them may not make sense as they may be checked before entering the function, but I fixed them all in this patch. I submit this fix because 1) similar checks are found in some other places in the LLVM codebase for the same return value of the function; and, 2) some of the pointers are dereferenced before they are checked, which may definitely trigger a null pointer dereference if the return value is nullptr.

Reviewed By: tejohnson, MaskRay, jpienaar

Differential Revision: https://reviews.llvm.org/D91410
2020-11-21 21:04:12 -08:00
Eugene Zhulenev
d4f1a3c6e2 [mlir] Add microbenchmark for linalg+async-parallel-for
Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D91896
2020-11-21 03:47:14 -08:00
Eugene Zhulenev
a86a9b5ef7 [mlir] Automatic reference counting for Async values + runtime support for ref counted objects
Depends On D89963

**Automatic reference counting algorithm outline:**

1. `ReturnLike` operations forward the reference counted values without
    modifying the reference count.
2. Use liveness analysis to find blocks in the CFG where the lifetime of
   reference counted values ends, and insert `drop_ref` operations after
   the last use of the value.
3. Insert `add_ref` before the `async.execute` operation capturing the
   value, and pairing `drop_ref` before the async body region terminator,
   to release the captured reference counted value when execution
   completes.
4. If the reference counted value is passed only to some of the block
   successors, insert `drop_ref` operations in the beginning of the blocks
   that do not have reference coutned value uses.

Reviewed By: silvas

Differential Revision: https://reviews.llvm.org/D90716
2020-11-20 03:08:44 -08:00
River Riddle
65fcddff24 [mlir][BuiltinDialect] Resolve comments from D91571
* Move ops to a BuiltinOps.h
* Add file comments
2020-11-19 11:12:49 -08:00
River Riddle
73ca690df8 [mlir][NFC] Remove references to Module.h and Function.h
These includes have been deprecated in favor of BuiltinDialect.h, which contains the definitions of ModuleOp and FuncOp.

Differential Revision: https://reviews.llvm.org/D91572
2020-11-17 00:55:47 -08:00
Eugene Zhulenev
c30ab6c2a3 [mlir] Transform scf.parallel to scf.for + async.execute
Depends On D89958

1. Adds `async.group`/`async.awaitall` to group together multiple async tokens/values
2. Rewrite scf.parallel operation into multiple concurrent async.execute operations over non overlapping subranges of the original loop.

Example:

```
   scf.for (%i, %j) = (%lbi, %lbj) to (%ubi, %ubj) step (%si, %sj) {
     "do_some_compute"(%i, %j): () -> ()
   }
```

Converted to:

```
   %c0 = constant 0 : index
   %c1 = constant 1 : index

   // Compute blocks sizes for each induction variable.
   %num_blocks_i = ... : index
   %num_blocks_j = ... : index
   %block_size_i = ... : index
   %block_size_j = ... : index

   // Create an async group to track async execute ops.
   %group = async.create_group

   scf.for %bi = %c0 to %num_blocks_i step %c1 {
     %block_start_i = ... : index
     %block_end_i   = ... : index

     scf.for %bj = %c0 t0 %num_blocks_j step %c1 {
       %block_start_j = ... : index
       %block_end_j   = ... : index

       // Execute the body of original parallel operation for the current
       // block.
       %token = async.execute {
         scf.for %i = %block_start_i to %block_end_i step %si {
           scf.for %j = %block_start_j to %block_end_j step %sj {
             "do_some_compute"(%i, %j): () -> ()
           }
         }
       }

       // Add produced async token to the group.
       async.add_to_group %token, %group
     }
   }

   // Await completion of all async.execute operations.
   async.await_all %group
```
In this example outer loop launches inner block level loops as separate async
execute operations which will be executed concurrently.

At the end it waits for the completiom of all async execute operations.

Reviewed By: ftynse, mehdi_amini

Differential Revision: https://reviews.llvm.org/D89963
2020-11-13 04:02:56 -08:00
Aart Bik
0846659648 [mlir][sparse] export sparse tensor runtime support through header file
Exposing the C versions of the methods of the sparse runtime support lib
through header files will enable using the same methods in an MLIR program
as well as a C++ program, which will simplify future benchmarking comparisons
(e.g. comparing MLIR generated code with eigen for Matrix Market sparse matrices).

Reviewed By: penpornk

Differential Revision: https://reviews.llvm.org/D91316
2020-11-11 21:03:39 -08:00
Paul Lietar
6fd9e59e1b [mlir] Fix exports in mlir_async_runtime
The MLIR_ASYNCRUNTIME_EXPORT macro was being defined to be either
__declspec(dllexport) or __declspec(dllimport), depending on whether
mlir_c_runner_utils_EXPORTS is defined. The latter was a copy/paste
error and should have been mlir_async_runtime_EXPORTS.

Additionally, the uses of that macro in the .cpp file were unnecessary,
as only function declarations need to be exported, not their definitions.

Differential Revision: https://reviews.llvm.org/D91196
2020-11-11 14:11:16 +00:00
Eugene Zhulenev
f6c9f6eccd [mlir] JitRunner: add a config option to register symbols with ExecutionEngine at runtime
Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D90264
2020-10-27 15:57:34 -07:00
George Mitenkov
89808ce734 [MLIR][mlir-spirv-cpu-runner] A SPIR-V cpu runner prototype
This patch introduces a SPIR-V runner. The aim is to run a gpu
kernel on a CPU via GPU -> SPIRV -> LLVM conversions. This is a first
prototype, so more features will be added in due time.

- Overview
The runner follows similar flow as the other runners in-tree. However,
having converted the kernel to SPIR-V, we encode the bind attributes of
global variables that represent kernel arguments. Then SPIR-V module is
converted to LLVM. On the host side, we emulate passing the data to device
by creating in main module globals with the same symbolic name as in kernel
module. These global variables are later linked with ones from the nested
module. We copy data from kernel arguments to globals, call the kernel
function from nested module and then copy the data back.

- Current state
At the moment, the runner is capable of running 2 modules, nested one in
another. The kernel module must contain exactly one kernel function. Also,
the runner supports rank 1 integer memref types as arguments (to be scaled).

- Enhancement of JitRunner and ExecutionEngine
To translate nested modules to LLVM IR, JitRunner and ExecutionEngine were
altered to take an optional (default to `nullptr`) function reference that
is a custom LLVM IR module builder. This allows to customize LLVM IR module
creation from MLIR modules.

Reviewed By: ftynse, mravishankar

Differential Revision: https://reviews.llvm.org/D86108
2020-10-26 09:09:29 -04:00
Mehdi Amini
4bde9aa964 Add CMake dependency from MLIRJitRunner on all dialects
This dependency was already existing indirectly, but is now more direct
since the registration relies on a inline function. This fixes the
link of the tools with BFD.
2020-10-24 01:24:05 +00:00
Mehdi Amini
e7021232e6 Remove global dialect registration
This has been deprecated for >1month now and removal was announced in:

https://llvm.discourse.group/t/rfc-revamp-dialect-registration/1559/11

Differential Revision: https://reviews.llvm.org/D86356
2020-10-24 00:35:55 +00:00
Mehdi Amini
6a72635881 Revert "Remove global dialect registration"
This reverts commit b22e2e4c6e.

Investigating broken builds
2020-10-23 21:26:48 +00:00
Mehdi Amini
b22e2e4c6e Remove global dialect registration
This has been deprecated for >1month now and removal was announced in:

https://llvm.discourse.group/t/rfc-revamp-dialect-registration/1559/11

Differential Revision: https://reviews.llvm.org/D86356
2020-10-23 20:41:44 +00:00
Eugene Zhulenev
b16f6324db [mlir] Link with pthreads in AsyncRuntime
AsyncRuntime must be explicitly linked with LLVM pthreads

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D89983
2020-10-23 12:52:51 -07:00
Lei Zhang
36ce915ac5 Revert "Revert "[mlir] Convert from Async dialect to LLVM coroutines""
This reverts commit 4986d5eaff with
proper patches to CMakeLists.txt:

- Add MLIRAsync as a dependency to MLIRAsyncToLLVM
- Add Coroutines as a dependency to MLIRExecutionEngine
2020-10-22 15:23:11 -04:00
Mehdi Amini
4986d5eaff Revert "[mlir] Convert from Async dialect to LLVM coroutines"
This reverts commit a8b0ae3bdd
and commit f8fcff5a9d.

The build with SHARED_LIBRARY=ON is broken.
2020-10-22 19:12:19 +00:00
Eugene Zhulenev
a8b0ae3bdd [mlir] Do not start threads in AsyncRuntime
pthreads is not enabled for all builds by default

Reviewed By: jpienaar

Differential Revision: https://reviews.llvm.org/D89967
2020-10-22 08:31:30 -07:00
Eugene Zhulenev
f8fcff5a9d [mlir] Convert from Async dialect to LLVM coroutines
Lower from Async dialect to LLVM by converting async regions attached to `async.execute` operations into LLVM coroutines (https://llvm.org/docs/Coroutines.html):
1. Outline all async regions to functions
2. Add LLVM coro intrinsics to mark coroutine begin/end
3. Use MLIR conversion framework to convert all remaining async types and ops to LLVM + Async runtime function calls

All `async.await` operations inside async regions converted to coroutine suspension points. Await operation outside of a coroutine converted to the blocking wait operations.

Implement simple runtime to support concurrent execution of coroutines.

Reviewed By: herhut

Differential Revision: https://reviews.llvm.org/D89292
2020-10-22 06:30:46 -07:00