Default atomic ordering information is processed in the OpenMP dialect
to LLVM IR lowering stage at every spot where an operation can be
affected by it. The rest of clauses are stored globally in the
OpenMPIRBuilderConfig object before starting that lowering stage, so
that the OMPIRBuilder can conditionally modify code generation
depending on these. At the end of the process, the omp.requires
attribute is itself lowered into a global constructor that passes these
clauses as flags to the OpenMP runtime.
Depends on D147217, D147218 and D158278.
Differential Revision: https://reviews.llvm.org/D147219
The OpenACC standard specifies an `atomic` construct in section 2.12 (of
3.3 spec), used to ensure that a specific location is accessed or
updated atomically. Four different clauses are allowed: `read`, `write`,
`update`, or `capture`. If no clause appears, it is as if `update` is
used.
The OpenMP specification defines the same clauses for `omp atomic`. The
types of expression and the clauses in the OpenACC spec match the OpenMP
spec exactly. The main difference is that the OpenMP specification is a
superset - it includes clauses for `hint` and `memory order`. It also
allows conditional expression statements. But otherwise, the expression
definition matches.
Thus, for OpenACC, we refactor and reuse the OpenMP implementation as
follows:
* The atomic operations are duplicated in OpenACC dialect. This is
preferable so that each language's semantics are precisely represented
even if specs have divergence.
* However, since semantics overlap, a common interface between the
atomic operations is being added. The semantics for the interfaces are
not generic enough to be used outside of OpenACC and OpenMP, and thus
new folders were added to hold common pieces of the two dialects.
* The atomic interfaces define common accessors (such as getting `x` or
`v`) which match the OpenMP and OpenACC specs. It also adds common
verifiers intended to be called by each dialect's operation verifier.
* The OpenMP write operation was updated to use `x` and `expr` to be
consistent with its other operations (that use naming based on spec).
The frontend lowering necessary to generate the dialect can also be
reused. This will be done in a follow up change.
This patch fixes a compiler crash that would happen during translation to LLVM
IR if the optional `map` argument of the `omp.target` operation was not
present. A unit test is added to ensure this has been fixed.
Differential Revision: https://reviews.llvm.org/D158722
This patch extends the existing WsLoop reduction IR generation to parallel blocks.
Reviewed By: kiranchandramohan
Differential Revision: https://reviews.llvm.org/D155157
This patch adds code emission in emitTargetCall to call the OpenMP runtime to
launch an kernel, and to call the fallback host implementation if the launch
fails.
Reviewed By: TIFitis, kiranchandramohan, jdoerfert
Differential Revision: https://reviews.llvm.org/D155633
This patch improves the implementation of a recent function filtering
workaround to address problems uncovered by D154247.
In particular, the problem was related to the removal of functions called from
within target regions. Since target regions have to remain until LLVM IR is
generated, removing these functions from MLIR results in undefined references
any time there are calls to them in a target region. This patch modifies the
MLIR function filtering pass to make these functions "external" rather than
removing them. This way, the processing and lowering of MLIR functions that
will eventually be discarded is still prevented, but no calls to undefined
functions remain either.
Additionally, the approach of just filtering host-only functions during device
compilation, and not filtering device-only functions during host compilation,
is maintained. This is because code generation for device-only functions is
required for host fallback to work.
Depends on D156988
Differential Revision: https://reviews.llvm.org/D155827
Added MLIR support for translating use_device_ptr and use_device_addr clauses for LLVMIR lowering.
- use_device_ptr: The mapped variables marked with use_device_ptr are accessed through a copy of the base pointer mappers. The mapper is copied onto a new temporary pointer variable.
- use_device_addr: The mapped variables marked with use_device_addr are accessed directly through the base pointer mappers.
- If mapping information is not provided explicitly then default map_type of alloc/release is assumed and the map_size is set to 0.
Depends on D152554
Reviewed By: kiranchandramohan, raghavendhra
Differential Revision: https://reviews.llvm.org/D146648
This patch permits map operands to be not specified for the target
data operation. Also emit an error if none of the map, use_device_addr,
or use_device_ptr operands are specified.
Reviewed By: TIFitis
Differential Revision: https://reviews.llvm.org/D156170
This patch adds support for selecting which functions are lowered to LLVM IR
from MLIR depending on declare target information and whether host or device
code is being generated.
The approach proposed by this patch is to perform the filtering in two stages:
- An MLIR transformation pass, which is added to the Flang translation flow
after the `OMPEarlyOutliningPass`. The functions that are kept are those
that match the OpenMP processor (host or device) the compiler invocation
is targeting, according to the presence of the `-fopenmp-is-target-device`
compiler option and declare target information. All functions contaning an
`omp.target` are also kept, regardless of the declare target information of
the function, due to the need for keeping target regions visible for both
host and device compilation.
- A filtering step during translation to LLVM IR, which is peformed for those
functions that were kept because of the presence of a target region inside.
If the targeted OpenMP processor does not match the declare target
information of the function, then it is removed from the LLVM IR after its
contents have been processed and translated. Since they should only contain
an omp.target operation which, in turn, should have been outlined into
another LLVM IR function, the wrapper can be deleted at that point.
Depends on D150328 and D150329.
Differential Revision: https://reviews.llvm.org/D147641
This patch implements an early outlining transform of omp.target operations in
flang. The pass is needed because optimizations may cross target op region
boundaries, but with the outlining the resulting functions only contain a
single omp.target op plus a func.return, so there should not be any opportunity
to optimize across region boundaries.
The patch also adds an interface to be able to store and retrieve the parent
function name of the original target operation. This is needed to be able to
create correct kernel function names when lowering to LLVM-IR.
Reviewed By: kiranchandramohan, domada
Differential Revision: https://reviews.llvm.org/D154879
Key changes:
- Refactor the createTargetData function to make use of the emitOffloadingArrays and emitOffloadingArraysArgument functions to generate code.
- Added a new emitIfClause helper function to allow handling if clauses in a similar fashion to Clang.
- Updated the MLIR side of code to account for changes to createTargetData.
Depends on D149872
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D146557
MLIR version attribute should be lowered to LLVM IR module metadata.
The lowering is done by OpenMPIRBuilder.
Differential Revision: https://reviews.llvm.org/D150574
Reviewed By: kiranchandramohan
This patch adds support in the `OpenMPIRBuilder` for generating working
device code for OpenMP target regions. It generates and handles the
result of a call to `__kmpc_target_init()` at the beginning of the
function resulting from outlining each target region, and it also
generates the matching `__kmpc_target_deinit()` call before returning.
It relies on the implementation of target region outlining for host
codegen to handle the production of the new function and the lowering of
its body based on the contents of the associated target region.
Depends on D147172
Differential Revision: https://reviews.llvm.org/D147940
The MLIR classes Type/Attribute/Operation/Op/Value support
cast/dyn_cast/isa/dyn_cast_or_null functionality through llvm's doCast
functionality in addition to defining methods with the same name.
This change begins the migration of uses of the method to the
corresponding function call as has been decided as more consistent.
Note that there still exist classes that only define methods directly,
such as AffineExpr, and this does not include work currently to support
a functional cast/isa call.
Caveats include:
- This clang-tidy script probably has more problems.
- This only touches C++ code, so nothing that is being generated.
Context:
- https://mlir.llvm.org/deprecation/ at "Use the free function variants
for dyn_cast/cast/isa/…"
- Original discussion at https://discourse.llvm.org/t/preferred-casting-style-going-forward/68443
Implementation:
This first patch was created with the following steps. The intention is
to only do automated changes at first, so I waste less time if it's
reverted, and so the first mass change is more clear as an example to
other teams that will need to follow similar steps.
Steps are described per line, as comments are removed by git:
0. Retrieve the change from the following to build clang-tidy with an
additional check:
https://github.com/llvm/llvm-project/compare/main...tpopp:llvm-project:tidy-cast-check
1. Build clang-tidy
2. Run clang-tidy over your entire codebase while disabling all checks
and enabling the one relevant one. Run on all header files also.
3. Delete .inc files that were also modified, so the next build rebuilds
them to a pure state.
4. Some changes have been deleted for the following reasons:
- Some files had a variable also named cast
- Some files had not included a header file that defines the cast
functions
- Some files are definitions of the classes that have the casting
methods, so the code still refers to the method instead of the
function without adding a prefix or removing the method declaration
at the same time.
```
ninja -C $BUILD_DIR clang-tidy
run-clang-tidy -clang-tidy-binary=$BUILD_DIR/bin/clang-tidy -checks='-*,misc-cast-functions'\
-header-filter=mlir/ mlir/* -fix
rm -rf $BUILD_DIR/tools/mlir/**/*.inc
git restore mlir/lib/IR mlir/lib/Dialect/DLTI/DLTI.cpp\
mlir/lib/Dialect/Complex/IR/ComplexDialect.cpp\
mlir/lib/**/IR/\
mlir/lib/Dialect/SparseTensor/Transforms/SparseVectorization.cpp\
mlir/lib/Dialect/Vector/Transforms/LowerVectorMultiReduction.cpp\
mlir/test/lib/Dialect/Test/TestTypes.cpp\
mlir/test/lib/Dialect/Transform/TestTransformDialectExtension.cpp\
mlir/test/lib/Dialect/Test/TestAttributes.cpp\
mlir/unittests/TableGen/EnumsGenTest.cpp\
mlir/test/python/lib/PythonTestCAPI.cpp\
mlir/include/mlir/IR/
```
Differential Revision: https://reviews.llvm.org/D150123
This patch adds lowering of TargetOps for the host. The lowering outlines the
target region function and uses the OpenMPIRBuilder support functions to emit
the function and call. Code generation for offloading will be done in later
patches.
Reviewed By: kiranchandramohan, jdoerfert, agozillon
Differential Revision: https://reviews.llvm.org/D147172
The omp::FlagsAttr contains OpenMP RTL flags
given by a user to the compiler and a frontend
(flang currently) then populates the omp::FlagsAttr
which will then lower these to LLVM globals
which are utilised by the OpenMP runtime.
Reviewers: jdoerfert
Differential Revision: https://reviews.llvm.org/D147344
This patch adds OpenMP IRBuilder support for the Target Data directives to allow lowering to LLVM IR.
The mlir::Translation is responsible for generating supporting code for processing the map_operands through the processMapOperand function, and also generate code for the r>
The OMPIRBuilder is responsible for generating the begin and end mapper function calls.
Limitations:
- use_device_ptr and use_device_addr clauses are NOT supported for Target Data operation.
- nowait clauses are NOT supported for Target Enter and Exit Data operations.
- Only LLVMPointerType is supported for map_operands.
Differential Revision: https://reviews.llvm.org/D142914
This patch adds support for the OpenMP 4.0 depend clause (in, out,
inout) of the task construct to the definition of the OpenMP MLIR
dialect and translation from MLIR to LLVM IR using OMPIRBuilder.
Reviewed By: kiranchandramohan
Differential Revision: https://reviews.llvm.org/D142730
The current OpenMP implementation assumes the use of typed pointers (or rather typed pointer like types). Given the support for typed pointers in LLVM is now pending removal, the OpenMP Dialect should be able to support opaque pointers as well, given that any users of it must lower OpenMP through the LLVM Dialect.
This patch fixes the above and adds support for using LLVM opaque pointers with the OpenMP dialect. This is implemented by making all related code not make use of the element type of pointer arguments. The few (one) op requiring a pointer element type now use an explicit `TypeAttr` for representing the element type.
More concretely, the list of changes are:
* `omp.atomic.read` now has an extra `TypeAttr` (also in syntax) which is the element type of the values read and stored from the operands
* `omp.reduction` now has an type argument in the syntax for both the accmulator and operand since the operand type can no longer be inferred from the accumulator
* `OpenMPToLLVMIRTranslation.cpp` was rewritten to never query element types of pointers
* Adjusted the verifier to be able to handle pointers without element types
Differential Revision: https://reviews.llvm.org/D143582
The patch adds operations to `BlockAndValueMapping` and renames it to `IRMapping`. When operations are cloned, old operations are mapped to the cloned operations. This allows mapping from an operation to a cloned operation. Example:
```
Operation *opWithRegion = ...
Operation *opInsideRegion = &opWithRegion->front().front();
IRMapping map
Operation *newOpWithRegion = opWithRegion->clone(map);
Operation *newOpInsideRegion = map.lookupOrNull(opInsideRegion);
```
Migration instructions:
All includes to `mlir/IR/BlockAndValueMapping.h` should be replaced with `mlir/IR/IRMapping.h`. All uses of `BlockAndValueMapping` need to be renamed to `IRMapping`.
Reviewed By: rriddle, mehdi_amini
Differential Revision: https://reviews.llvm.org/D139665
This is part of an effort to migrate from llvm::Optional to
std::optional. This patch changes the way mlir-tblgen generates .inc
files, and modifies tests and documentation appropriately. It is a "no
compromises" patch, and doesn't leave the user with an unpleasant mix of
llvm::Optional and std::optional.
A non-trivial change has been made to ControlFlowInterfaces to split one
constructor into two, relating to a build failure on Windows.
See also: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
Signed-off-by: Ramkumar Ramachandra <r@artagnon.com>
Differential Revision: https://reviews.llvm.org/D138934
Currently generation of align assumptions for OpenMP simd construct is done
outside OMPIRBuilder for C code and it is not supported for Fortran.
According to OpenMP 5.0 standard (2.9.3) only pointers and arrays can be
aligned for C code.
If given aligned variable is pointer, then Clang generates the following set
of the LLVM IR isntructions to support simd align clause:
; memory allocation for pointer address:
%A.addr = alloca ptr, align 8
; some LLVM IR code
; Alignment instructions (alignment is equal to 32):
%0 = load ptr, ptr %A.addr, align 8
call void @llvm.assume(i1 true) [ "align"(ptr %0, i64 32) ]
If given aligned variable is array, then Clang generates the following set
of the LLVM IR isntructions to support simd align clause:
; memory allocation for array:
%B = alloca [10 x i32], align 16
; some LLVM IR code
; Alignment instructions (alignment is equal to 32):
%arraydecay = getelementptr inbounds [10 x i32], ptr %B, i64 0, i64 0
call void @llvm.assume(i1 true) [ "align"(ptr %arraydecay, i64 32) ]
OMPIRBuilder was modified to generate aligned assumptions. It generates only
llvm.assume calls. Frontend is responsible for generation of aligned pointer
and getting the default alignment value if user does not specify it in aligned
clause.
Unit and regression tests were added to check if aligned clause was handled correctly.
Differential Revision: https://reviews.llvm.org/D133578
Reviewed By: jdoerfert
If 'order(concurrent)' clause is specified, then the iterations of SIMD loop
can be executed concurrently.
This patch adds support for LLVM IR codegen via OMPIRBuilder for SIMD loop
with 'order(concurrent)' clause. The functionality added to OMPIRBuilder is
similar to the functionality implemented in 'CodeGenFunction::EmitOMPSimdInit'.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D134046
Signed-off-by: Dominik Adamski <dominik.adamski@amd.com>
This patch adds translation from OpenMP Dialect to LLVM IR for
omp.taskgroup. This patch also adds missing tests for the clauses in
omp.taskgroup operation.
Reviewed By: peixin
Differential Revision: https://reviews.llvm.org/D130157
This supports translation from MLIR to LLVM IR using OMPIRBuilder for
OpenMP safelen clause in SIMD construct.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D132245
This patch adds OMPIRBuilder support for the safelen clause for the
simd directive.
Reviewed By: shraiysh, Meinersbur
Differential Revision: https://reviews.llvm.org/D131526
Scope of changes:
1) Added new function to generate loop versioning
2) Added support for if clause to applySimd function
2) Added tests which confirm that lowering is successful
If ifCond is specified, then collapsed loop is duplicated and if branch
is added. Duplicated loop is executed if simd ifCond is evaluated to false.
Reviewed By: Meinersbur
Differential Revision: https://reviews.llvm.org/D129368
Signed-off-by: Dominik Adamski <dominik.adamski@amd.com>
This supports lowering from parse-tree to MLIR and translation from
MLIR to LLVM IR using OMPIRBuilder for OpenMP simdlen clause in SIMD
construct.
Reviewed By: shraiysh, peixin, arnamoy10
Differential Revision: https://reviews.llvm.org/D130195
This patch adds OMPIRBuilder support for the simdlen clause for the
simd directive. It uses the simdlen support in OpenMPIRBuilder when
it is enabled in Clang. Simdlen is lowered by OpenMPIRBuilder by
generating the loop.vectorize.width metadata.
Reviewed By: jdoerfert, Meinersbur
Differential Revision: https://reviews.llvm.org/D129149
