8 Commits

Author SHA1 Message Date
River Riddle
8d67d187ba [mlir][DialectConversion] Refactor how block argument types get converted
This revision removes the TypeConverter parameter passed to the apply* methods, and instead moves the responsibility of region type conversion to patterns. The types of a region can be converted using the 'convertRegionTypes' method, which acts similarly to the existing 'applySignatureConversion'. This method ensures that all blocks within, and including those moved into, a region will have the block argument types converted using the provided converter.

This has the benefit of making more of the legalization logic controlled by patterns, instead of being handled explicitly by the driver. It also opens up the possibility to support multiple type conversions at some point in the future.

This revision also adds a new utility class `FailureOr<T>` that provides a LogicalResult friendly facility for returning a failure or a valid result value.

Differential Revision: https://reviews.llvm.org/D81681
2020-06-18 15:59:22 -07:00
River Riddle
552ef9fc09 [mlir][DialectConversion] Add overload of addDynamicallyLegalDialect to support lambdas
This allows for passing a lambda to addDynamicallyLegalDialect without needing to explicit wrap with Optional<DynamicLegalityCallbackFn>.

Differential Revision: https://reviews.llvm.org/D81680
2020-06-15 15:57:44 -07:00
River Riddle
0e360744f3 [mlir][DialectConversion] Cache type conversions and add a few useful helpers
It is quite common for the same type to be converted many types throughout the conversion process, and there isn't any good reason why we aren't caching that result. Especially given that we currently use identity conversion to signify legality. This revision also adds a few additional helpers to TypeConverter.

Differential Revision: https://reviews.llvm.org/D81679
2020-06-15 15:57:43 -07:00
Ehsan Toosi
4214031d43 [mlir] Introduce allowMemrefFunctionResults for the helper operation converters of buffer placement
This parameter gives the developers the freedom to choose their desired function
signature conversion for preparing their functions for buffer placement. It is
introduced for BufferAssignmentFuncOpConverter, and also for
BufferAssignmentReturnOpConverter, and BufferAssignmentCallOpConverter to adapt
the return and call operations with the selected function signature conversion.
If the parameter is set, buffer placement won't also deallocate the returned
buffers.

Differential Revision: https://reviews.llvm.org/D81137
2020-06-08 09:25:41 +02:00
Ehsan Toosi
3f6a35e3ff [mlir] Introduce CallOp converter for buffer placement
Add BufferAssignmentCallOpConverter as a pattern rewriter for Buffer
Placement. It matches the signature of the caller operation with the callee
after rewriting the callee with FunctionAndBlockSignatureConverter.

Differential Revision: https://reviews.llvm.org/D80785
2020-06-02 11:35:24 +02:00
Ehsan Toosi
7a3a253585 [MLIR][BufferPlacement] Support functions that return Memref typed results
Buffer placement can now operates on functions that return buffers. These
buffers escape from the deallocation phase of buffer placement.

Differential Revision: https://reviews.llvm.org/D80696
2020-05-29 11:03:22 +02:00
Ehsan Toosi
3468300511 [MLIR] Update the FunctionAndBlockSignatureConverter and NonVoidToVoidReturnOpConverter of Buffer Assignment
Making these two converters more generic. FunctionAndBlockSignatureConverter now
moves only memref results (after type conversion) to the function argument and
keeps other legal function results unchanged. NonVoidToVoidReturnOpConverter is
renamed to NoBufferOperandsReturnOpConverter. It removes only the buffer
operands from the operands of the converted ReturnOp and inserts CopyOps to copy
each buffer to the target function argument.

Differential Revision: https://reviews.llvm.org/D79329
2020-05-19 17:04:59 +02:00
Ehsan Toosi
5c352e69e7 Providing buffer assignment for MLIR
We have provided a generic buffer assignment transformation ported from
TensorFlow. This generic transformation pass automatically analyzes the values
and their aliases (also in other blocks) and returns the valid positions for
Alloc and Dealloc operations. To find these positions, the algorithm uses the
block Dominator and Post-Dominator analyses. In our proposed algorithm, we have
considered aliasing, liveness, nested regions, branches, conditional branches,
critical edges, and independency to custom block terminators. This
implementation doesn't support block loops. However, we have considered this in
our design. For this purpose, it is only required to have a loop analysis to
insert Alloc and Dealloc operations outside of these loops in some special
cases.

Differential Revision: https://reviews.llvm.org/D78484
2020-04-28 10:17:59 +02:00