Commit Graph

195 Commits

Author SHA1 Message Date
Tres Popp 511dd4f438 Revert "Reorder MLIRContext location in BuiltinAttributes.h"
This reverts commit 7827753f98.
2021-02-08 09:32:42 +01:00
Tres Popp 7827753f98 Reorder MLIRContext location in BuiltinAttributes.h
Now the context is the first, rather than the last input.

This better matches the rest of the infrastructure and makes
it easier to move these types to being declaratively specified.

Differential Revision: https://reviews.llvm.org/D96111
2021-02-08 09:28:09 +01:00
River Riddle e21adfa32d [mlir] Mark LogicalResult as LLVM_NODISCARD
This makes ignoring a result explicit by the user, and helps to prevent accidental errors with dropped results. Marking LogicalResult as no discard was always the intention from the beginning, but got lost along the way.

Differential Revision: https://reviews.llvm.org/D95841
2021-02-04 15:10:10 -08:00
Nicolas Vasilache 49c9c3a59e [mlir][Standard] Extend n-D vector lowering to LLVM to [s|z]exti ops.
[s|z]exti ops do not have the same operand and result type.
As a consequence, the lowering of the n-D vector form needs to be relaxed a bit.
This revision additionally performs a few NFC renamings of variables to make them more intuitive.

Differential Revision: https://reviews.llvm.org/D95760
2021-02-02 07:45:50 +00:00
Nicolas Vasilache 7e6fe5c48a [mlir] Fix subview verifier.
The subview verifier in the rank-reduced case is plainly skipping verification
when the resulting type is a memref with empty affine map. This is generally incorrect.

Instead, form the actual expected rank-reduced MemRefType that takes into account the projections of 1's dimensions. Then, check the canonicalized expected rank-reduced type against the canonicalized candidate type.

Differential Revision: https://reviews.llvm.org/D95316
2021-01-28 13:55:39 +00:00
Nicolas Vasilache 5133673df4 [mlir] Extend semantic of OffsetSizeAndStrideOpInterface.
OffsetSizeAndStrideOpInterface now have the ability to specify only a leading subset of
offset, sizes, strides operands/attributes.
The size of that leading subset must be limited by the corresponding entry in `getArrayAttrMaxRanks` to avoid overflows.
Missing trailing dimensions are assumed to span the whole range (i.e. [0 .. dim)).
This brings more natural semantics to slice-like op on top of subview and is a simplifies to removing all uses of SliceOp in dependent projects.

Differential revision: https://reviews.llvm.org/D95441
2021-01-27 09:02:35 +00:00
Alexander Belyaev fc58bfd02f [mlir] Remove complex ops from Standard dialect.
`complex` dialect should be used instead.
https://llvm.discourse.group/t/rfc-split-the-complex-dialect-from-std/2496/2

Differential Revision: https://reviews.llvm.org/D95077
2021-01-21 10:34:26 +01:00
Alex Zinenko bd30a796fc [mlir] use built-in vector types instead of LLVM dialect types when possible
Continue the convergence between LLVM dialect and built-in types by using the
built-in vector type whenever possible, that is for fixed vectors of built-in
integers and built-in floats. LLVM dialect vector type is still in use for
pointers, less frequent floating point types that do not have a built-in
equivalent, and scalable vectors. However, the top-level `LLVMVectorType` class
has been removed in favor of free functions capable of inspecting both built-in
and LLVM dialect vector types: `LLVM::getVectorElementType`,
`LLVM::getNumVectorElements` and `LLVM::getFixedVectorType`. Additional work is
necessary to design an implemented the extensions to built-in types so as to
remove the `LLVMFixedVectorType` entirely.

Note that the default output format for the built-in vectors does not have
whitespace around the `x` separator, e.g., `vector<4xf32>` as opposed to the
LLVM dialect vector type format that does, e.g., `!llvm.vec<4 x fp128>`. This
required changing the FileCheck patterns in several tests.

Reviewed By: mehdi_amini, silvas

Differential Revision: https://reviews.llvm.org/D94405
2021-01-12 10:04:28 +01:00
Christian Sigg d59ddba777 [mlir] Fix gpu-to-llvm lowering for gpu.alloc with dynamic sizes.
Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D94402
2021-01-11 15:55:48 +01:00
Adrian Kuegel af339f89a1 Remove redundant casts.
Differential Revision: https://reviews.llvm.org/D94305
2021-01-11 08:51:47 +01:00
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
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
Alex Zinenko a7cbc32a91 [mlir] remove a use of deprecated OpState::setAttr 2021-01-07 14:20:36 +01:00
Ivan Butygin c1d58c2b00 [mlir] Add fastmath flags support to some LLVM dialect ops
Add fastmath enum, attributes to some llvm dialect ops, `FastmathFlagsInterface` op interface, and `translateModuleToLLVMIR` support.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D92485
2021-01-07 14:00:09 +01:00
Alex Zinenko c69c9e0f0f [mlir] Remove LLVMType, LLVM dialect types now derive Type directly
BEGIN_PUBLIC
[mlir] Remove LLVMType, LLVM dialect types now derive Type directly

This class has become a simple `isa` hook with no proper functionality.
Removing will allow us to eventually make the LLVM dialect type infrastructure
open, i.e., support non-LLVM types inside container types, which itself will
make the type conversion more progressive.

Introduce a call `LLVM::isCompatibleType` to be used instead of
`isa<LLVMType>`. For now, this is strictly equivalent.
END_PUBLIC

Depends On D93681

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D93713
2021-01-05 17:36:54 +01:00
Alex Zinenko 7ed9cfc7b1 [mlir] Remove static constructors from LLVMType
LLVMType contains numerous static constructors that were initially introduced
for API compatibility with LLVM. Most of these merely forward to arguments to
`SpecificType::get` (MLIR defines classes for all types, unlike LLVM IR), while
some introduce subtle semantics differences due to different modeling of MLIR
types (e.g., structs are not auto-renamed in case of conflicts). Furthermore,
these constructors don't match MLIR idioms and actively prevent us from making
the LLVM dialect type system more open. Remove them and use `SpecificType::get`
instead.

Depends On D93680

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D93681
2020-12-23 13:12:47 +01:00
Christian Sigg 19a0d0a40c [mlir] Rename ConvertToLLVMPattern::isSupportedMemRefType() to isConvertibleAndHasIdentityMaps().
Reviewed By: ftynse, herhut

Differential Revision: https://reviews.llvm.org/D93752
2020-12-23 12:23:29 +01:00
Christian Sigg 8451d4872e [mlir] NFC: Remove ConvertToLLVMPattern::getDataPtr(). All call sites use getStridedElementPtr() now.
Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D93751
2020-12-23 11:35:01 +01:00
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
River Riddle fc5cf50e89 [mlir] Remove the MutableDictionaryAttr class
This class used to serve a few useful purposes:
* Allowed containing a null DictionaryAttr
* Provided some simple mutable API around a DictionaryAttr

The first of which is no longer an issue now that there is much better caching support for attributes in general, and a cache in the context for empty dictionaries. The second results in more trouble than it's worth because it mutates the internal dictionary on every action, leading to a potentially large number of dictionary copies. NamedAttrList is a much better alternative for the second use case, and should be modified as needed to better fit it's usage as a DictionaryAttrBuilder.

Differential Revision: https://reviews.llvm.org/D93442
2020-12-17 17:18:42 -08:00
Tres Popp c77ea40528 [mlir] Add std.pow lowering to LLVMIR
Differential Revision: https://reviews.llvm.org/D93311
2020-12-15 18:54:29 +01:00
Christian Sigg 1ffc1aaa09 [mlir] Use mlir::OpState::operator->() to get to methods of mlir::Operation.
This is a preparation step to remove those methods from OpState.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D93098
2020-12-13 09:58:16 +01:00
Christian Sigg 0bf4a82a5a [mlir] Use mlir::OpState::operator->() to get to methods of mlir::Operation. This is a preparation step to remove the corresponding methods from OpState.
Reviewed By: silvas, rriddle

Differential Revision: https://reviews.llvm.org/D92878
2020-12-09 12:11:32 +01:00
Christian Sigg dcec2ca5bd Remove typeConverter from ConvertToLLVMPattern and use the existing one in ConversionPattern.
ftynse

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D92564
2020-12-04 14:27:16 +01:00
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
Christian Sigg c4a0405902 Add `Operation* OpState::operator->()` to provide more convenient access to members of Operation.
Given that OpState already implicit converts to Operator*, this seems reasonable.

The alternative would be to add more functions to OpState which forward to Operation.

Reviewed By: rriddle, ftynse

Differential Revision: https://reviews.llvm.org/D92266
2020-12-02 15:46:20 +01:00
Christian Sigg acb69f3b7c [mlir] Change ConvertOpToLLVMPattern::matchAndRewrite argument to concrete operand type.
Reviewed By: herhut, ftynse

Differential Revision: https://reviews.llvm.org/D92111
2020-11-28 13:09:25 +01:00
Alex Zinenko 9bb5bff570 [mlir] Add an assertion on creating an Operation with null result types
Null types are commonly used as an error marker. Catch them in the constructor
of Operation if they are present in the result type list, as otherwise this
could lead to further surprising behavior when querying op result types.

Fix AsyncToLLVM and StandardToLLVM that were using null types when constructing
operations.

Reviewed By: rriddle

Differential Revision: https://reviews.llvm.org/D91770
2020-11-19 22:28:38 +01:00
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
Christian Sigg 8b97e17d16 [mlir] Simplify code generated by ConvertToLLVMPattern::getStridedElementPtr().
Make the interface match the one of ConvertToLLVMPattern::getDataPtr() (to be removed in a separate change).

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D91599
2020-11-18 11:52:09 +01:00
Christian Sigg bedaad4495 [mlir] Simplify std.alloc lowering to LLVM.
std.alloc only supports memrefs with identity layout, which means we can simplify the lowering to LLVM and compute strides only from (static and dynamic) sizes.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D91549
2020-11-17 18:55:34 +01:00
Christian Sigg 43ede0e2a7 [mlir] Remove unused ConvertToLLVMPattern::linearizeSubscripts().
Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D91594
2020-11-17 17:25:45 +01:00
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
Christian Sigg 04481f26fa [mlir] Require std.alloc() ops to have canonical layout during LLVM lowering.
The current code allows strided layouts, but the number of elements allocated is ambiguous. It could be either the number of elements in the shape (the current implementation), or the amount of elements required to not index out-of-bounds with the given maps (which would require evaluating the layout map).

If we require the canonical layouts, the two will be the same.

Reviewed By: nicolasvasilache, ftynse

Differential Revision: https://reviews.llvm.org/D91523
2020-11-16 17:29:36 +01:00
Rahul Joshi 5883c4b470 [MLIR] Fix standard -> LLVM conversion to fail for unsupported memref element type.
- Move isSupportedMemRefType() to ConvertToLLVMPatterns and check if the
  memref element type is supported there.

Differential Revision: https://reviews.llvm.org/D91374
2020-11-12 17:06:05 -08:00
Alexander Belyaev 9d02e0e38d [mlir][std] Add ExpandOps pass.
The pass combines patterns of ExpandAtomic, ExpandMemRefReshape,
StdExpandDivs passes. The pass is meant to legalize STD for conversion to LLVM.

Differential Revision: https://reviews.llvm.org/D91082
2020-11-09 21:58:28 +01:00
Rahul Joshi e29cb0908b [MLIR] Fix GCC build failure 2020-11-09 11:57:52 -08:00
Rahul Joshi a97e357e8e [MLIR] Support `global_memref` and `get_global_memref` in standard -> LLVM conversion.
- Convert `global_memref` to LLVM::GlobalOp.
- Convert `get_global_memref` to a memref descriptor with a pointer to the first element
  of the global stashed in it.
- Extend unit test and a mlir-cpu-runner test to validate the generated LLVM IR.

Differential Revision: https://reviews.llvm.org/D90803
2020-11-09 10:54:21 -08:00
Rahul Joshi 8c2025cc61 [MLIR] Refactor memref type -> LLVM Type conversion
- Eliminate duplicated information about mapping from memref -> its descriptor fields
  by consolidating that mapping in two functions:  getMemRefDescriptorFields and
  getUnrankedMemRefDescriptorFields.
- Change convertMemRefType() and convertUnrankedMemRefType() to use these
  functions.
- Remove convertMemrefSignature and convertUnrankedMemrefSignature.

Differential Revision: https://reviews.llvm.org/D90707
2020-11-04 10:32:56 -08:00
Mehdi Amini c7994bd939 Switch from C-style comments `/* ... */` to C++ style `//` (NFC)
This is mostly a scripted update, it may not be perfect.

function replace() {
  FROM=$1
  TO=$2
  git grep "$FROM" $REPO_PATH |cut -f 1 -d : | sort -u | \
    while read file; do
      sed -i "s#$FROM#$TO#" $file ;
    done
}

replace '|\*===----------------------------------------------------------------------===\*|$' '//===----------------------------------------------------------------------===//'
replace '^/\* =' '//=='
replace '^/\*=' '//='
replace '^\\\*=' '//='
replace '^|\*' '//'
replace ' \*|$' ''
replace '=\*\\$' '=//'
replace '== \*/$' '===//'
replace '==\*/$' '==//'
replace '^/\*\*\(.*\)\*/$' '///\1'
replace '^/\*\(.*\)\*/$' '//\1'
replace '//============================================================================//' '//===----------------------------------------------------------------------===//'

Differential Revision: https://reviews.llvm.org/D90732
2020-11-04 18:11:13 +00:00
Alexander Belyaev 9925168576 [mlir] Convert `memref_reshape` to LLVM.
https://llvm.discourse.group/t/rfc-standard-memref-cast-ops/1454/15

Differential Revision: https://reviews.llvm.org/D90377
2020-11-03 11:39:08 +01:00
Alexander Belyaev 7a996027b9 [mlir] Convert memref_reshape to memref_reinterpret_cast.
Differential Revision: https://reviews.llvm.org/D90235
2020-10-28 21:15:32 +01:00
Kazuaki Ishizaki 41b09f4eff [mlir] NFC: fix trivial typos
fix typos in comments and documents

Reviewed By: jpienaar

Differential Revision: https://reviews.llvm.org/D90089
2020-10-29 04:05:22 +09:00
River Riddle 3fffffa882 [mlir][Pattern] Add a new FrozenRewritePatternList class
This class represents a rewrite pattern list that has been frozen, and thus immutable. This replaces the uses of OwningRewritePatternList in pattern driver related API, such as dialect conversion. When PDL becomes more prevalent, this API will allow for optimizing a set of patterns once without the need to do this per run of a pass.

Differential Revision: https://reviews.llvm.org/D89104
2020-10-26 18:01:06 -07:00
Alexander Belyaev d6ab0474c6 [mlir] Convert MemRefReinterpretCastOp to LLVM.
https://llvm.discourse.group/t/rfc-standard-memref-cast-ops/1454/15

Differential Revision: https://reviews.llvm.org/D90033
2020-10-26 20:13:17 +01:00
Alexander Belyaev 323fd11df7 [mlir][nfc] Add a func to compute numElements of a shape in Std -> LLVM.
For some reason the variable `cumulativeSizeInBytes` in
`getCumulativeSizeInBytes` was actually storing number of elements. I decided
to fix it and refactor the function a bit.

Differential Revision: https://reviews.llvm.org/D89336
2020-10-13 21:41:25 +02:00
Jakub Lichman e547b1e243 [mlir] Rank reducing subview conversion to LLVM
This commit adjusts SubViewOp lowering to take rank reduction into account.

Differential Revision: https://reviews.llvm.org/D88883
2020-10-08 13:47:22 +00:00
Mehdi Amini afd729edee Add definition for static constexpr member (NFC)
Fix the build for some toolchain and config.
2020-10-05 16:56:27 +00:00
Christian Sigg 665371d0b2 [mlir] Split alloc-like op LLVM lowerings into base and separate derived classes.
The previous code did the lowering to alloca, malloc, and aligned_malloc
in a single class with different code paths that are somewhat difficult to
follow.

This change moves the common code to a base class and has a separte
derived class per lowering target that contains the specifics.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D88696
2020-10-05 17:36:01 +02:00
Benjamin Kramer 6e2b267d1c Promote transpose from linalg to standard dialect
While affine maps are part of the builtin memref type, there is very
limited support for manipulating them in the standard dialect. Add
transpose to the set of ops to complement the existing view/subview ops.
This is a metadata transformation that encodes the transpose into the
strides of a memref.

I'm planning to use this when lowering operations on strided memrefs,
using the transpose to remove the stride without adding a dependency on
linalg dialect.

Differential Revision: https://reviews.llvm.org/D88651
2020-10-05 10:58:20 +02:00
Diego Caballero a611f9a5c6 [mlir] Fix call op conversion in bare-ptr calling convention
We hit an llvm_unreachable related to unranked memrefs for call ops
with scalar types. Removing the llvm_unreachable since the conversion
should gracefully bail out in the presence of unranked memrefs. Adding
tests to verify that.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D88709
2020-10-02 08:48:21 -07:00
Diego Caballero a89fc12653 [mlir] Support return and call ops in bare-ptr calling convention
This patch adds support for the 'return' and 'call' ops to the bare-ptr
calling convention. These changes also align the bare-ptr calling
convention code with the latest changes in the default calling convention
and reduce the amount of customization code needed.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D87724
2020-09-29 12:00:47 -07:00
Rahul Joshi 08e4f07852 [MLIR][NFC] Adopt use of TypeRange in build() methods.
- Use TypeRange instead of ArrayRef<Type> where possible.
- Change some of the custom builders to also use TypeRange

Differential Revision: https://reviews.llvm.org/D87944
2020-09-23 09:07:57 -07:00
Alex Zinenko 967c7b6936 [mlir] check for failures when packing function sigunatures in std->llvm conversion
When packing function results into a structure during the standard-to-llvm
dialect conversion, do not assume the conversion was successful and propagate
nullptr as error state.

Fixes PR45184.

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D87605
2020-09-15 12:30:44 +02:00
Alex Zinenko 5cac85c931 [mlir] Check for type conversion success in std->llvm function conversion
Type converter may fail and return nullptr on unconvertible types. The function
conversion did not include a check and was attempting to use a nullptr type to
construct an LLVM function, leading to a crash. Add a check and return early.
The rest of the call stack propagates errors properly.

Fixes PR47403.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D87075
2020-09-14 13:16:42 +02:00
Christian Sigg 3a577f5446 Rename MemRefDescriptor::getElementType() to MemRefDescriptor::getElementPtrType().
Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D87284
2020-09-09 11:45:39 +02:00
Nicolas Vasilache 8d64df9f13 [mlir][Vector] Revisit VectorToSCF.
Vector to SCF conversion still had issues due to the interaction with the natural alignment derived by the LLVM data layout. One traditional workaround is to allocate aligned. However, this does not always work for vector sizes that are non-powers of 2.

This revision implements a more portable mechanism where the intermediate allocation is always a memref of elemental vector type. AllocOp is extended to use the natural LLVM DataLayout alignment for non-scalar types, when the alignment is not specified in the first place.

An integration test is added that exercises the transfer to scf.for + scalar lowering with a 5x5 transposition.

Differential Revision: https://reviews.llvm.org/D87150
2020-09-07 05:19:43 -04:00
River Riddle 431bb8b318 [mlir][ODS] Use c++ types for integer attributes of fixed width when possible.
Unsigned and Signless attributes use uintN_t and signed attributes use intN_t, where N is the fixed width. The 1-bit variants use bool.

Differential Revision: https://reviews.llvm.org/D86739
2020-09-01 13:43:32 -07:00
Mars Saxman d34df52377 Implement FPToUI and UIToFP ops in standard dialect
Add the unsigned complements to the existing FPToSI and SIToFP operations in the
standard dialect, with one-to-one lowerings to the corresponding LLVM operations.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D85557
2020-08-19 22:49:09 +02:00
Mehdi Amini f9dc2b7079 Separate the Registration from Loading dialects in the Context
This changes the behavior of constructing MLIRContext to no longer load globally
registered dialects on construction. Instead Dialects are only loaded explicitly
on demand:
- the Parser is lazily loading Dialects in the context as it encounters them
during parsing. This is the only purpose for registering dialects and not load
them in the context.
- Passes are expected to declare the dialects they will create entity from
(Operations, Attributes, or Types), and the PassManager is loading Dialects into
the Context when starting a pipeline.

This changes simplifies the configuration of the registration: a compiler only
need to load the dialect for the IR it will emit, and the optimizer is
self-contained and load the required Dialects. For example in the Toy tutorial,
the compiler only needs to load the Toy dialect in the Context, all the others
(linalg, affine, std, LLVM, ...) are automatically loaded depending on the
optimization pipeline enabled.

To adjust to this change, stop using the existing dialect registration: the
global registry will be removed soon.

1) For passes, you need to override the method:

virtual void getDependentDialects(DialectRegistry &registry) const {}

and registery on the provided registry any dialect that this pass can produce.
Passes defined in TableGen can provide this list in the dependentDialects list
field.

2) For dialects, on construction you can register dependent dialects using the
provided MLIRContext: `context.getOrLoadDialect<DialectName>()`
This is useful if a dialect may canonicalize or have interfaces involving
another dialect.

3) For loading IR, dialect that can be in the input file must be explicitly
registered with the context. `MlirOptMain()` is taking an explicit registry for
this purpose. See how the standalone-opt.cpp example is setup:

  mlir::DialectRegistry registry;
  registry.insert<mlir::standalone::StandaloneDialect>();
  registry.insert<mlir::StandardOpsDialect>();

Only operations from these two dialects can be in the input file. To include all
of the dialects in MLIR Core, you can populate the registry this way:

  mlir::registerAllDialects(registry);

4) For `mlir-translate` callback, as well as frontend, Dialects can be loaded in
the context before emitting the IR: context.getOrLoadDialect<ToyDialect>()

Differential Revision: https://reviews.llvm.org/D85622
2020-08-19 01:19:03 +00:00
Mehdi Amini e75bc5c791 Revert "Separate the Registration from Loading dialects in the Context"
This reverts commit d14cf45735.
The build is broken with GCC-5.
2020-08-19 01:19:03 +00:00
Mehdi Amini d14cf45735 Separate the Registration from Loading dialects in the Context
This changes the behavior of constructing MLIRContext to no longer load globally
registered dialects on construction. Instead Dialects are only loaded explicitly
on demand:
- the Parser is lazily loading Dialects in the context as it encounters them
during parsing. This is the only purpose for registering dialects and not load
them in the context.
- Passes are expected to declare the dialects they will create entity from
(Operations, Attributes, or Types), and the PassManager is loading Dialects into
the Context when starting a pipeline.

This changes simplifies the configuration of the registration: a compiler only
need to load the dialect for the IR it will emit, and the optimizer is
self-contained and load the required Dialects. For example in the Toy tutorial,
the compiler only needs to load the Toy dialect in the Context, all the others
(linalg, affine, std, LLVM, ...) are automatically loaded depending on the
optimization pipeline enabled.

To adjust to this change, stop using the existing dialect registration: the
global registry will be removed soon.

1) For passes, you need to override the method:

virtual void getDependentDialects(DialectRegistry &registry) const {}

and registery on the provided registry any dialect that this pass can produce.
Passes defined in TableGen can provide this list in the dependentDialects list
field.

2) For dialects, on construction you can register dependent dialects using the
provided MLIRContext: `context.getOrLoadDialect<DialectName>()`
This is useful if a dialect may canonicalize or have interfaces involving
another dialect.

3) For loading IR, dialect that can be in the input file must be explicitly
registered with the context. `MlirOptMain()` is taking an explicit registry for
this purpose. See how the standalone-opt.cpp example is setup:

  mlir::DialectRegistry registry;
  registry.insert<mlir::standalone::StandaloneDialect>();
  registry.insert<mlir::StandardOpsDialect>();

Only operations from these two dialects can be in the input file. To include all
of the dialects in MLIR Core, you can populate the registry this way:

  mlir::registerAllDialects(registry);

4) For `mlir-translate` callback, as well as frontend, Dialects can be loaded in
the context before emitting the IR: context.getOrLoadDialect<ToyDialect>()

Differential Revision: https://reviews.llvm.org/D85622
2020-08-18 23:23:56 +00:00
Mehdi Amini d84fe55e0d Revert "Separate the Registration from Loading dialects in the Context"
This reverts commit e1de2b7550.
Broke a build bot.
2020-08-18 22:16:34 +00:00
Mehdi Amini e1de2b7550 Separate the Registration from Loading dialects in the Context
This changes the behavior of constructing MLIRContext to no longer load globally
registered dialects on construction. Instead Dialects are only loaded explicitly
on demand:
- the Parser is lazily loading Dialects in the context as it encounters them
during parsing. This is the only purpose for registering dialects and not load
them in the context.
- Passes are expected to declare the dialects they will create entity from
(Operations, Attributes, or Types), and the PassManager is loading Dialects into
the Context when starting a pipeline.

This changes simplifies the configuration of the registration: a compiler only
need to load the dialect for the IR it will emit, and the optimizer is
self-contained and load the required Dialects. For example in the Toy tutorial,
the compiler only needs to load the Toy dialect in the Context, all the others
(linalg, affine, std, LLVM, ...) are automatically loaded depending on the
optimization pipeline enabled.

To adjust to this change, stop using the existing dialect registration: the
global registry will be removed soon.

1) For passes, you need to override the method:

virtual void getDependentDialects(DialectRegistry &registry) const {}

and registery on the provided registry any dialect that this pass can produce.
Passes defined in TableGen can provide this list in the dependentDialects list
field.

2) For dialects, on construction you can register dependent dialects using the
provided MLIRContext: `context.getOrLoadDialect<DialectName>()`
This is useful if a dialect may canonicalize or have interfaces involving
another dialect.

3) For loading IR, dialect that can be in the input file must be explicitly
registered with the context. `MlirOptMain()` is taking an explicit registry for
this purpose. See how the standalone-opt.cpp example is setup:

  mlir::DialectRegistry registry;
  mlir::registerDialect<mlir::standalone::StandaloneDialect>();
  mlir::registerDialect<mlir::StandardOpsDialect>();

Only operations from these two dialects can be in the input file. To include all
of the dialects in MLIR Core, you can populate the registry this way:

  mlir::registerAllDialects(registry);

4) For `mlir-translate` callback, as well as frontend, Dialects can be loaded in
the context before emitting the IR: context.getOrLoadDialect<ToyDialect>()
2020-08-18 21:14:39 +00:00
Rob Suderman 5556575230 Added std.floor operation to match std.ceil
There should be an equivalent std.floor op to std.ceil. This includes
matching lowerings for SPIRV, NVVM, ROCDL, and LLVM.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D85940
2020-08-18 10:25:32 -07:00
Alex Zinenko 168213f91c [mlir] Move data layout from LLVMDialect to module Op attributes
Legacy implementation of the LLVM dialect in MLIR contained an instance of
llvm::Module as it was required to parse LLVM IR types. The access to the data
layout of this module was exposed to the users for convenience, but in practice
this layout has always been the default one obtained by parsing an empty layout
description string. Current implementation of the dialect no longer relies on
wrapping LLVM IR types, but it kept an instance of DataLayout for
compatibility. This effectively forces a single data layout to be used across
all modules in a given MLIR context, which is not desirable. Remove DataLayout
from the LLVM dialect and attach it as a module attribute instead. Since MLIR
does not yet have support for data layouts, use the LLVM DataLayout in string
form with verification inside MLIR. Introduce the layout when converting a
module to the LLVM dialect and keep the default "" description for
compatibility.

This approach should be replaced with a proper MLIR-based data layout when it
becomes available, but provides an immediate solution to compiling modules with
different layouts, e.g. for GPUs.

This removes the need for LLVMDialectImpl, which is also removed.

Depends On D85650

Reviewed By: aartbik

Differential Revision: https://reviews.llvm.org/D85652
2020-08-17 15:12:36 +02:00
Mehdi Amini 25ee851746 Revert "Separate the Registration from Loading dialects in the Context"
This reverts commit 2056393387.

Build is broken on a few bots
2020-08-15 09:21:47 +00:00
Mehdi Amini 2056393387 Separate the Registration from Loading dialects in the Context
This changes the behavior of constructing MLIRContext to no longer load globally registered dialects on construction. Instead Dialects are only loaded explicitly on demand:
- the Parser is lazily loading Dialects in the context as it encounters them during parsing. This is the only purpose for registering dialects and not load them in the context.
- Passes are expected to declare the dialects they will create entity from (Operations, Attributes, or Types), and the PassManager is loading Dialects into the Context when starting a pipeline.

This changes simplifies the configuration of the registration: a compiler only need to load the dialect for the IR it will emit, and the optimizer is self-contained and load the required Dialects. For example in the Toy tutorial, the compiler only needs to load the Toy dialect in the Context, all the others (linalg, affine, std, LLVM, ...) are automatically loaded depending on the optimization pipeline enabled.

Differential Revision: https://reviews.llvm.org/D85622
2020-08-15 08:07:31 +00:00
Mehdi Amini ba92dadf05 Revert "Separate the Registration from Loading dialects in the Context"
This was landed by accident, will reland with the right comments
addressed from the reviews.
Also revert dependent build fixes.
2020-08-15 07:35:10 +00:00
Mehdi Amini ebf521e784 Separate the Registration from Loading dialects in the Context
This changes the behavior of constructing MLIRContext to no longer load globally registered dialects on construction. Instead Dialects are only loaded explicitly on demand:
- the Parser is lazily loading Dialects in the context as it encounters them during parsing. This is the only purpose for registering dialects and not load them in the context.
- Passes are expected to declare the dialects they will create entity from (Operations, Attributes, or Types), and the PassManager is loading Dialects into the Context when starting a pipeline.

This changes simplifies the configuration of the registration: a compiler only need to load the dialect for the IR it will emit, and the optimizer is self-contained and load the required Dialects. For example in the Toy tutorial, the compiler only needs to load the Toy dialect in the Context, all the others (linalg, affine, std, LLVM, ...) are automatically loaded depending on the optimization pipeline enabled.
2020-08-14 09:40:27 +00:00
Alex Zinenko 339eba0805 [mlir] do not emit bitcasts between structs in StandardToLLVM
The convresion of memref cast operaitons from the Standard dialect to the LLVM
dialect has been emitting bitcasts from a struct type to itself. Beyond being
useless, such casts are invalid as bitcast does not operate on aggregate types.
This kept working by accident because LLVM IR bitcast construction API skips
the construction if types are equal before it verifies that the types are
acceptable in a bitcast. Do not emit such bitcasts, the memref cast that only
adds/erases size information is in fact a noop on the current descriptor as it
always contains dynamic values for all sizes.

Reviewed By: pifon2a

Differential Revision: https://reviews.llvm.org/D85899
2020-08-14 11:33:10 +02:00
River Riddle 65277126bf [mlir][Type] Remove the remaining usages of Type::getKind in preparation for its removal
This revision removes all of the lingering usages of Type::getKind. A consequence of this is that FloatType is now split into 4 derived types that represent each of the possible float types(BFloat16Type, Float16Type, Float32Type, and Float64Type). Other than this split, this revision is NFC.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D85566
2020-08-12 19:33:58 -07:00
Christian Sigg 2c48e3629c [MLIR] Adding gpu.host_register op and lower it to a runtime call.
Reviewed By: herhut

Differential Revision: https://reviews.llvm.org/D85631
2020-08-10 22:46:17 +02:00
Alex Zinenko 87a89e0f77 [mlir] Remove llvm::LLVMContext and llvm::Module from mlir::LLVMDialectImpl
Original modeling of LLVM IR types in the MLIR LLVM dialect had been wrapping
LLVM IR types and therefore required the LLVMContext in which they were created
to outlive them, which was solved by placing the LLVMContext inside the dialect
and thus having the lifetime of MLIRContext. This has led to numerous issues
caused by the lack of thread-safety of LLVMContext and the need to re-create
LLVM IR modules, obtained by translating from MLIR, in different LLVM contexts
to enable parallel compilation. Similarly, llvm::Module had been introduced to
keep track of identified structure types that could not be modeled properly.

A recent series of commits changed the modeling of LLVM IR types in the MLIR
LLVM dialect so that it no longer wraps LLVM IR types and has no dependence on
LLVMContext and changed the ownership model of the translated LLVM IR modules.
Remove LLVMContext and LLVM modules from the implementation of MLIR LLVM
dialect and clean up the remaining uses.

The only part of LLVM IR that remains necessary for the LLVM dialect is the
data layout. It should be moved from the dialect level to the module level and
replaced with an MLIR-based representation to remove the dependency of the
LLVMDialect on LLVM IR library.

Reviewed By: rriddle

Differential Revision: https://reviews.llvm.org/D85445
2020-08-07 14:30:31 +02:00
Alexander Belyaev 3effc35015 [mlir] Lower DimOp to LLVM for unranked memrefs.
Differential Revision: https://reviews.llvm.org/D85361
2020-08-06 11:46:11 +02:00
Alex Zinenko 5446ec8507 [mlir] take MLIRContext instead of LLVMDialect in getters of LLVMType's
Historical modeling of the LLVM dialect types had been wrapping LLVM IR types
and therefore needed access to the instance of LLVMContext stored in the
LLVMDialect. The new modeling does not rely on that and only needs the
MLIRContext that is used for uniquing, similarly to other MLIR types. Change
LLVMType::get<Kind>Ty functions to take `MLIRContext *` instead of
`LLVMDialect *` as first argument. This brings the code base closer to
completely removing the dependence on LLVMContext from the LLVMDialect,
together with additional support for thread-safety of its use.

Depends On D85371

Reviewed By: rriddle

Differential Revision: https://reviews.llvm.org/D85372
2020-08-06 11:05:40 +02:00
Alex Zinenko d3a9807674 [mlir] Remove most uses of LLVMDialect::getModule
This prepares for the removal of llvm::Module and LLVMContext from the
mlir::LLVMDialect.

Reviewed By: rriddle

Differential Revision: https://reviews.llvm.org/D85371
2020-08-06 10:54:30 +02:00
Alexander Belyaev 9fdd0df949 [mlir][nfc] Rename `promoteMemRefDescriptors` to `promoteOperands`.
`promoteMemRefDescriptors` also converts types of every operand, not only
memref-typed ones. I think `promoteMemRefDescriptors` name does not imply that.

Differential Revision: https://reviews.llvm.org/D85325
2020-08-05 20:24:48 +02:00
Uday Bondhugula 1d75f004ab [MLIR][NFC] Fix clang-tidy warnings in std to llvm conversion
Fix clang-tidy warnings in std to llvm conversion.
2020-08-05 22:12:05 +05:30
Alexander Belyaev bc7456fd8a [mlir] Fix rank bitwidth in UnrankedMemRefType conversion.
Differential Revision: https://reviews.llvm.org/D85300
2020-08-05 18:35:23 +02:00
Arpith C. Jacob fab4b59961 [mlir] Conversion of ViewOp with memory space to LLVM.
Handle the case where the ViewOp takes in a memref that has
an memory space.

Reviewed By: ftynse, bondhugula, nicolasvasilache

Differential Revision: https://reviews.llvm.org/D85048
2020-08-05 12:19:52 +02:00
Alexander Belyaev a3d427d30c [mlir] Lower RankOp to LLVM for unranked memrefs.
Differential Revision: https://reviews.llvm.org/D85273
2020-08-05 12:13:43 +02:00
Alexander Belyaev 8979a9cdf2 [mlir] Fix adding wrong operand value in `promoteMemRefDescriptors`.
The bug was not noticed because we didn't have a lot of custom type conversions
directly to LLVM dialect.

Differential Revision: https://reviews.llvm.org/D85192
2020-08-04 13:39:56 +02:00
Alexander Belyaev 6b8c641d8e [mlir] NFC: Expose `getElementPtrType` and `getSizes` methods of AllocOpLowering.
Differential Revision: https://reviews.llvm.org/D84917
2020-07-30 20:18:29 +02:00
Christian Sigg 13a3d88666 [MLIR] Don't pass separate LowerToLLVMOptions when we already pass a LLVMTypeConverter which contains those options already.
This also prevents passing inconsistent options.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D84915
2020-07-30 14:55:23 +02:00
Alex Zinenko aec38c619d [mlir] LLVMType: make getUnderlyingType private
The current modeling of LLVM IR types in MLIR is based on the LLVMType class
that wraps a raw `llvm::Type *` and delegates uniquing, printing and parsing to
LLVM itself. This is model makes thread-safe type manipulation hard and is
being progressively replaced with a cleaner MLIR model that replicates the type
system. In the new model, LLVMType will no longer have an underlying LLVM IR
type. Restrict access to this type in the current model in preparation for the
change.

Reviewed By: nicolasvasilache

Differential Revision: https://reviews.llvm.org/D84389
2020-07-29 13:43:38 +02:00
Frederik Gossen fb1e571687 [MLIR][Standard] Add default lowering for `assert`
The default lowering of `assert` calls `abort` in case the assertion is
violated. The failure message is ignored but should be used by custom lowerings
that can assume more about their environment.

Differential Revision: https://reviews.llvm.org/D83886
2020-07-24 08:31:12 +00:00
River Riddle 4589dd924d [mlir][DialectConversion] Enable deeper integration of type conversions
This revision adds support for much deeper type conversion integration into the conversion process, and enables auto-generating cast operations when necessary. Type conversions are now largely automatically managed by the conversion infra when using a ConversionPattern with a provided TypeConverter. This removes the need for patterns to do type cast wrapping themselves and moves the burden to the infra. This makes it much easier to perform partial lowerings when type conversions are involved, as any lingering type conversions will be automatically resolved/legalized by the conversion infra.

To support this new integration, a few changes have been made to the type materialization API on TypeConverter. Materialization has been split into three separate categories:
* Argument Materialization: This type of materialization is used when converting the type of block arguments when calling `convertRegionTypes`. This is useful for contextually inserting additional conversion operations when converting a block argument type, such as when converting the types of a function signature.
* Source Materialization: This type of materialization is used to convert a legal type of the converter into a non-legal type, generally a source type. This may be called when uses of a non-legal type persist after the conversion process has finished.
* Target Materialization: This type of materialization is used to convert a non-legal, or source, type into a legal, or target, type. This type of materialization is used when applying a pattern on an operation, but the types of the operands have not yet been converted.

Differential Revision: https://reviews.llvm.org/D82831
2020-07-23 19:40:31 -07:00
River Riddle 9db53a1827 [mlir][NFC] Remove usernames and google bug numbers from TODO comments.
These were largely leftover from when MLIR was a google project, and don't really follow LLVM guidelines.
2020-07-07 01:40:52 -07:00
Alex Zinenko 4ab4398045 [mlir] minor tweaks in standard-to-llvm lowering
Fix a typo in the documentation and simplify the condition to drop
braces. Addresses post-commit review of https://reviews.llvm.org/D82647.
2020-06-30 21:19:19 +02:00
Rahul Joshi ee394e6842 [MLIR] Add variadic isa<> for Type, Value, and Attribute
- Also adopt variadic llvm::isa<> in more places.
- Fixes https://bugs.llvm.org/show_bug.cgi?id=46445

Differential Revision: https://reviews.llvm.org/D82769
2020-06-29 15:04:48 -07:00
Christopher Tetreault 5cba1c6336 [SVE] Remove calls to VectorType::getNumElements from mlir
Reviewers: efriedma, ftynse, rriddle

Reviewed By: ftynse, rriddle

Subscribers: tschuett, rkruppe, psnobl, mehdi_amini, rriddle, jpienaar, shauheen, antiagainst, nicolasvasilache, arpith-jacob, mgester, lucyrfox, aartbik, liufengdb, stephenneuendorffer, Joonsoo, grosul1, Kayjukh, jurahul, msifontes

Tags: #mlir

Differential Revision: https://reviews.llvm.org/D82583
2020-06-29 10:29:39 -07:00
Tobias Gysi 10643c9ad8 [mlir] make the bitwidth of device side index computations configurable (reland)
Summary:
The patch makes the index type lowering of the GPU to NVVM/ROCDL conversion configurable. It introduces a pass option that controls the bitwidth used when lowering index computations and uses the LowerToLLVMOptions structure to control the Standard to LLVM lowering.

This commit fixes a use-after-free bug introduced by the reverted commit d10b1a3. It implements the following changes:
- Added a getDefaultOptions method to the LowerToLLVMOptions struct that returns a reference to statically allocated default options.
- Use the getDefaultOptions method to provide default LowerToLLVMOptions (instead of an initializer list).
- Added comments to clarify the required lifetime of the LowerToLLVMOptions

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D82475
2020-06-29 12:22:39 +02:00
Alex Zinenko cba733edf5 [mlir] LLVM dialect: use addressof instead of constant to create function pointers
`llvm.mlir.constant` was originally introduced as an LLVM dialect counterpart
to `std.constant`. As such, it was supporting "function pointer" constants
derived from the symbol name. This is different from `std.constant` that allows
for creation of a "function" constant since MLIR, unlike LLVM IR, supports
this. Later, `llvm.mlir.addressof` was introduced as an Op that obtains a
constant pointer to a global in the LLVM dialect. It naturally extends to
functions (in LLVM IR, functions are globals) and should be used for defining
"function pointer" values instead.

Fixes PR46344.

Differential Revision: https://reviews.llvm.org/D82667
2020-06-29 12:21:33 +02:00
Alex Zinenko 8304ab5799 [mlir] Avoid creating local OpBuilders in Standard-to-LLVM conversion
Conversions of allocation-related operations in Standard-to-LLVM need
declarations of "malloc" and "free" (or equivalents). They use locally created
OpBuilders pointed at the module level to declare these functions if necessary.
This is poorly compatible with the pattern infrastructure that is unaware of
new operations being created. Update the insertion point of the main rewriter
instead.

Differential Revision: https://reviews.llvm.org/D82649
2020-06-26 15:38:00 +02:00
Alex Zinenko 6323065fd6 [mlir] support returning unranked memrefs
Initially, unranked memref descriptors in the LLVM dialect were designed only
to be passed into functions. An assertion was guarding against returning
unranked memrefs from functions in the standard-to-LLVM conversion. This is
insufficient for functions that wish to return an unranked memref such that the
caller does not know the rank in advance, and hence cannot allocate the
descriptor and pass it in as an argument.

Introduce a calling convention for returning unranked memref descriptors as
follows. An unranked memref descriptor always points to a ranked memref
descriptor stored on stack of the current function. When an unranked memref
descriptor is returned from a function, the ranked memref descriptor it points
to is copied to dynamically allocated memory, the ownership of which is
transferred to the caller. The caller is responsible for deallocating the
dynamically allocated memory and for copying the pointed-to ranked memref
descriptor onto its stack.

Provide default lowerings for std.return, std.call and std.indirect_call that
maintain the conversion defined above.

This convention is additionally exercised by a runtime test to guard against
memory errors.

Differential Revision: https://reviews.llvm.org/D82647
2020-06-26 15:37:37 +02:00
Tobias Gysi 2ff6fad700 Revert "[mlir] make the bitwidth of device side index computations configurable"
This reverts commit d10b1a38a7.
2020-06-23 19:21:36 +02:00
Tobias Gysi d10b1a38a7 [mlir] make the bitwidth of device side index computations configurable
The patch makes the index type lowering of the GPU to NVVM/ROCDL
conversion configurable. It introduces a pass option that controls the
bitwidth used when lowering index computations.

Differential Revision: https://reviews.llvm.org/D80285
2020-06-22 11:43:37 +02:00
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
Frederik Gossen 0990f1a3ad [MLIR][Standard] Lower `std.dim` with dynamic dimension operand to LLVM
Implement the missing lowering from `std.dim` to the LLVM dialect in case of a
dynamic dimension.

Differential Revision: https://reviews.llvm.org/D81834
2020-06-16 20:57:42 +00:00