This has caused build failures when enabling opaque pointers for the GPU integration tests as could be seen here:
https://lab.llvm.org/buildbot/#/builders/220/builds/16946 and here https://lab.llvm.org/buildbot/#/builders/61/builds/40822
The gist of the issue was the use of a wrong pointer base type within a GEP. There sadly was no test coverage for either the generating of that GEP, nor is LLVM Dialects GEP verifier currently capable of catching such issues, so it went unnoticed until the integration tests actually attempted to convert it to LLVM IR.
Differential Revision: https://reviews.llvm.org/D145774
Part of https://discourse.llvm.org/t/rfc-switching-the-llvm-dialect-and-dialect-lowerings-to-opaque-pointers/68179
This patch adds the new pass option `use-opaque-pointers` to the GPU to LLVM lowerings (including ROCD and NVVM) and adapts the code to support using opaque pointers in addition to typed pointers.
The required changes mostly boil down to avoiding `getElementType` and specifying base types in GEP and Alloca.
In the future opaque pointers will be the only supported model, hence tests have been ported to using opaque pointers by default. Additional regression tests for typed-pointers have been added to avoid breaking existing clients.
Note: This does not yet port the `GpuToVulkan` passes.
Differential Revision: https://reviews.llvm.org/D144448
The runtime functions `memset` and `memcpy` are lowered are declared with pointers to the default address space (0) while their ops however are compatible with memrefs taking any address space.
Such cases do not cause any issues with MLIRs LLVM Dialect due to `bitcast`s verifier being too lenient at the moment, but actual LLVM IR does not allow casting between address spaces using `bitcast`: https://godbolt.org/z/3a1z97rc9
This patch fixes the issue by inserting an address space cast before the bitcast, to first cast the pointer into the correct address space before doing the bitcast.
Differential Revision: https://reviews.llvm.org/D143866
See https://github.com/llvm/llvm-project/issues/57475 for more context.
Using auto-generated constructors and options has significant advantages:
* It forces a uniform style and expectation for consuming a pass
* It allows to very easily add, remove or change options to a pass by simply making the changes in TableGen
* Its less code
This patch in particular ports all the conversion passes which lower to LLVM to use the auto generated constructors and options. For the most part, care was taken so that auto generated constructor functions have the same name as they previously did. Only following slight breaking changes (which I consider as worth the churn) have been made:
* `mlir::cf::createConvertControlFlowToLLVMPass` has been moved to the `mlir` namespace. This is consistent with basically all conversion passes
* `createGpuToLLVMConversionPass` now takes a proper options struct array for its pass options. The pass options are now also autogenerated.
* `LowerVectorToLLVMOptions` has been replaced by the autogenerated `ConvertVectorToLLVMPassOptions` which is automatically kept up to date by TableGen
* I had to move one function in the GPU to LLVM lowering as it is used as default value for an option.
* All passes that previously returned `unique_ptr<OperationPass<...>>` now simply return `unique_ptr<Pass>`
Differential Revision: https://reviews.llvm.org/D143773
Remapping memory spaces is a function often needed in type
conversions, most often when going to LLVM or to/from SPIR-V (a future
commit), and it is possible that such remappings may become more
common in the future as dialects take advantage of the more generic
memory space infrastructure.
Currently, memory space remappings are handled by running a
special-purpose conversion pass before the main conversion that
changes the address space attributes. In this commit, this approach is
replaced by adding a notion of type attribute conversions
TypeConverter, which is then used to convert memory space attributes.
Then, we use this infrastructure throughout the *ToLLVM conversions.
This has the advantage of loosing the requirements on the inputs to
those passes from "all address spaces must be integers" to "all
memory spaces must be convertible to integer spaces", a looser
requirement that reduces the coupling between portions of MLIR.
ON top of that, this change leads to the removal of most of the calls
to getMemorySpaceAsInt(), bringing us closer to removing it.
(A rework of the SPIR-V conversions to use this new system will be in
a folowup commit.)
As a note, one long-term motivation for this change is that I would
eventually like to add an allocaMemorySpace key to MLIR data layouts
and then call getMemRefAddressSpace(allocaMemorySpace) in the
relevant *ToLLVM in order to ensure all alloca()s, whether incoming or
produces during the LLVM lowering, have the correct address space for
a given target.
I expect that the type attribute conversion system may be useful in
other contexts.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D142159
Since the recent MemRef refactoring that centralizes the lowering of
complex MemRef operations outside of the conversion framework, the
MemRefToLLVM pass doesn't directly convert these complex operations.
Instead, to fully convert the whole MemRef dialect space, MemRefToLLVM
needs to run after `expand-strided-metadata`.
Make this more obvious by changing the name of the pass and the option
associated with it from `convert-memref-to-llvm` to
`finalize-memref-to-llvm`.
The word "finalize" conveys that this pass needs to run after something
else and that something else is documented in its tablegen description.
This is a follow-up patch related to the conversation at:
https://discourse.llvm.org/t/psa-you-need-to-run-expand-strided-metadata-before-memref-to-llvm-now/66956/14
Differential Revision: https://reviews.llvm.org/D142463
This is a purely mechanical change that introduces an enum attribute in the GPU
dialect to represent the various memref memory spaces as opposed to the
hard-coded integer attributes that are currently used.
The following steps were taken to make the transition across the codebase:
1. Introduce a pass "gpu-lower-memory-space-attributes":
The pass updates all memref types that have a memory space attribute that is a
`gpu::AddressSpaceAttr`. These attributes are changed to `IntegerAttr`'s using a
mapping that is given by the caller. This pass is based on the
"map-memref-spirv-storage-class" pass and the common functions can probably
be refactored into a set of utilities under the MemRef dialect.
2. Update the verifiers of GPU/NVGPU dialect operations.
If a verifier currently checks the address space of an operand using
e.g.`getWorkspaceAddressSpace`, then it can continue to do so. However, the
checks are changed to only fail if the memory space is either missing or a wrong
value of type `gpu::AddressSpaceAttr`. Otherwise, it just assumes the address
space is correct because it was specifically lowered to something other than a
`gpu::AddressSpaceAttr`.
3. Update existing gpu-to-llvm conversion infrastructure.
In the existing gpu-to-X passes, we add a full conversion equivalent to
`gpu-lower-memory-space-attributes` just before doing the conversion to the
LLVMDialect. This is done because currently both the gpu-to-llvm passes
(rocdl,nvvm) run gpu-to-gpu rewrites within the pass, which introduce
`AddressSpaceAttr` memory space annotations. Therefore, I inserted the
memory space conversion between the gpu-to-gpu rewrites and the LLVM
conversion.
For more context see the below discourse discussion:
https://discourse.llvm.org/t/gpu-workgroup-shared-memory-address-space-is-hard-coded/
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D140644
When converting to nvvm lowering gpu.printf to vprintf allows us to
support printing when running on cuda.
Differential Revision: https://reviews.llvm.org/D141049
1. When converting from the GPU dialect to the ROCDL dialect, if the
function that contains a gpu.thread_id or gpu.block_id op is annotated
with gpu.known_{block,grid}_size, use that size to set a "range"
attribute on the corresponding rocdl intrinsic so that the LLVM
frontend can optimize based on that range information.
1b. When translating from the rocdl dialect to LLVM IR, use the
"range" attribute, if present, to set !range metadata on the relevant
function call.
2. Deprecate the old rocdl.max_flat_work_group_size attribute, which
was used in a tensorflow backend. Instead, use
rocdl.flat_work_group_size going forward to allow kernel generators to
specify the minimum and maximum work group sizes a kernel may be
launched with in one attribute, thus more closely matching the backend.
3. When translating from gpu.func to llvm.func within gpu-to-rocdl,
copy the known_block_size attribute as rocdl.reqd_work_group_size to
enable further translations to set the corresponding metadata on the
LLVM IR function. Also, set the rocdl.flat_work_group_size attribute
to ensure that the reqd_work_group_size metadata and the
amdgpu-flat-work-group-size metadata are consistent.
3b. Extend the ROCDL to LLVM IR translation to set the
!reqd_work_group_size metadata on LLVM functions
Also update tests and add functions to the ROCDL dialect to ensure
attribute names are used consistently.
Depends on D139865
Reviewed By: antiagainst
Differential Revision: https://reviews.llvm.org/D139866
Reland D139447, D139471 With flang actually working
- FunctionOpInterface: make get/setFunctionType interface methods
This patch removes the concept of a `function_type`-named type attribute
as a requirement for implementors of FunctionOpInterface. Instead, this
type should be provided through two interface methods, `getFunctionType`
and `setFunctionTypeAttr` (*Attr because functions may use different
concrete function types), which should be automatically implemented by
ODS for ops that define a `$function_type` attribute.
This also allows FunctionOpInterface to materialize function types if
they don't carry them in an attribute, for example.
Importantly, all the function "helper" still accept an attribute name to
use in parsing and printing functions, for example.
- FunctionOpInterface: arg and result attrs dispatch to interface
This patch removes the `arg_attrs` and `res_attrs` named attributes as a
requirement for FunctionOpInterface and replaces them with interface
methods for the getters, setters, and removers of the relevent
attributes. This allows operations to use their own storage for the
argument and result attributes.
Reviewed By: jpienaar
Differential Revision: https://reviews.llvm.org/D139736
and "[mlir] Fix examples build"
This reverts commit fbc253fe81da4e1d6bfa2519e01e03f21d8c40a8 and
96cf183bccd7d1c3083f169a89a6af1f263b3aae.
Which I missed in the first revert in f3379feabe38fd3711b13ffcf6de4aab03b7ccdc.
This patch removes the concept of a `function_type`-named type attribute
as a requirement for implementors of FunctionOpInterface. Instead, this
type should be provided through two interface methods, `getFunctionType`
and `setFunctionTypeAttr` (*Attr because functions may use different
concrete function types), which should be automatically implemented by
ODS for ops that define a `$function_type` attribute.
This also allows FunctionOpInterface to materialize function types if
they don't carry them in an attribute, for example.
Importantly, all the function "helper" still accept an attribute name to
use in parsing and printing functions, for example.
Reviewed By: rriddle, lattner
Differential Revision: https://reviews.llvm.org/D139447
Improve type conversion error propagation/failure during LLVM lowering.
BEFORE
```
llvm-mlir/mlir/lib/Conversion/LLVMCommon/TypeConverter.cpp:304: SmallVector<mlir::Type, 5> mlir::LLVMTypeConverter::getMemRefDescriptorFields(mlir::MemRefType, bool): Assertion `isStrided(type) && "Non-strided layout maps must have been normalized away"' failed.
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
Stack dump:
...
```
AFTER
```
<unknown>:0: error: integer overflow during size computation
<unknown>:0: error: Conversion to strided form failed either due to non-strided layout maps (which should have been normalized away) or other reasons
<unknown>:0: error: failed to legalize operation 'gpu.func' that was explicitly marked illegal
<unknown>:0: note: see current operation:
"gpu.func"() ( {
...
```
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D139072
Unroll ops that map to intrinsics when lowering to LLVM, because intrinsics don't support vector operands/results.
Reviewed By: herhut
Differential Revision: https://reviews.llvm.org/D136345
Motivation: we have lowering pipeline based on upstream gpu and spirv dialects and and we are using host shared gpu memory to transfer data between host and device.
Add `host_shared` flag to `gpu.alloc` to distinguish between shared and device-only gpu memory allocations.
Differential Revision: https://reviews.llvm.org/D133533
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure.
Reviewed By: mehdi_amini, rriddle
Differential Review: https://reviews.llvm.org/D132838
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure.
Reviewed By: mehdi_amini, rriddle
Differential Review: https://reviews.llvm.org/D132838
mlir::TypedValue is a wrapper class for mlir::Values with a known type
getType will return the known type and all assignements will be checked
Also the tablegen Operation generator was adapted to use mlir::TypedValue
when appropriate
In the ROCm runtime (and probably CUDA as well), all kernel arguments
are aligned. Therefore, enable using bare pointers for memref
arguments to kernels when these memrefs have static shape and a
trivial layout.
This is a substantial optimization to launching kernels that use
memrefs with known, static sizes, since it causes the kernel launch
packet to no longer include information already known to the kernel,
which can enable packing the kernel launch arguments into launch
packets instead of having to allocate an entire separate structure to
hold unneeded memref information.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D130716
This is the follow up on https://reviews.llvm.org/D130730 which goes through upstream code and removes creating constant values in favour of using the constant indices in GEP directly. This leads to less and more readable code and more compact IR as well.
Differential Revision: https://reviews.llvm.org/D130731
This patch adds support for Calling Convention attribute in LLVM
dialect, including enums, custom syntax and import from LLVM IR.
Additionally fix import of dso_local attribute.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D126161
This removes any potential confusion with the `getType` accessors
which correspond to SSA results of an operation, and makes it
clear what the intent is (i.e. to represent the type of the function).
Differential Revision: https://reviews.llvm.org/D121762
The current StandardToLLVM conversion patterns only really handle
the Func dialect. The pass itself adds patterns for Arithmetic/CFToLLVM, but
those should be/will be split out in a followup. This commit focuses solely
on being an NFC rename.
Aside from the directory change, the pattern and pass creation API have been renamed:
* populateStdToLLVMFuncOpConversionPattern -> populateFuncToLLVMFuncOpConversionPattern
* populateStdToLLVMConversionPatterns -> populateFuncToLLVMConversionPatterns
* createLowerToLLVMPass -> createConvertFuncToLLVMPass
Differential Revision: https://reviews.llvm.org/D120778
The Func has a large number of legacy dependencies carried over from the old
Standard dialect, which was pervasive and contained a large number of varied
operations. With the split of the standard dialect and its demise, a lot of lingering
dead dependencies have survived to the Func dialect. This commit removes a
large majority of then, greatly reducing the dependence surface area of the
Func dialect.
The last remaining operations in the standard dialect all revolve around
FuncOp/function related constructs. This patch simply handles the initial
renaming (which by itself is already huge), but there are a large number
of cleanups unlocked/necessary afterwards:
* Removing a bunch of unnecessary dependencies on Func
* Cleaning up the From/ToStandard conversion passes
* Preparing for the move of FuncOp to the Func dialect
See the discussion at https://discourse.llvm.org/t/standard-dialect-the-final-chapter/6061
Differential Revision: https://reviews.llvm.org/D120624
This op is added to allow MLIR code running on multi-GPU systems to
select the GPU they want to execute operations on when no GPU is
otherwise specified.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D119883
OwningRewritePatternList has been deprecated for ~10 months now, we can remove
the leftover using directives at this point.
Differential Revision: https://reviews.llvm.org/D118287
This commit refactors the FunctionLike trait into an interface (FunctionOpInterface).
FunctionLike as it is today is already a pseudo-interface, with many users checking the
presence of the trait and then manually into functionality implemented in the
function_like_impl namespace. By transitioning to an interface, these accesses are much
cleaner (ideally with no direct calls to the impl namespace outside of the implementation
of the derived function operations, e.g. for parsing/printing utilities).
I've tried to maintain as much compatability with the current state as possible, while
also trying to clean up as much of the cruft as possible. The general migration plan for
current users of FunctionLike is as follows:
* function_like_impl -> function_interface_impl
Realistically most user calls should remove references to functions within this namespace
outside of a vary narrow set (e.g. parsing/printing utilities). Calls to the attribute name
accessors should be migrated to the `FunctionOpInterface::` equivalent, most everything
else should be updated to be driven through an instance of the interface.
* OpTrait::FunctionLike -> FunctionOpInterface
`hasTrait` checks will need to be moved to isa, along with the other various Trait vs
Interface API differences.
* populateFunctionLikeTypeConversionPattern -> populateFunctionOpInterfaceTypeConversionPattern
Fixes#52917
Differential Revision: https://reviews.llvm.org/D117272
In LLVM IR, the GEP indices that correspond to structures are required to be
i32 constants. MLIR models constants as just values defined by special
operations, and there is no verification that it is the case for structure
indices in GEP. Furthermore, some common transformations such as control flow
simplification may lead to the operands becoming non-constant. Make it possible
to directly supply constant values to LLVM GEPOp to guarantee they remain
constant until the translation to LLVM IR. This is not yet a requirement and
the verifier is not modified, this will be introduced separately.
Reviewed By: wsmoses
Differential Revision: https://reviews.llvm.org/D116757
Each attribute has two accessor: one suffixed with `Attr` which returns the attribute itself
and one without the suffix which unwrap the attribute.
For example for a StringAttr attribute with a field named `kind`, we'll generate:
StringAttr getKindAttr();
StringRef getKind();
Differential Revision: https://reviews.llvm.org/D116466
- Define a gpu.printf op, which can be lowered to any GPU printf() support (which is present in CUDA, HIP, and OpenCL). This op only supports constant format strings and scalar arguments
- Define the lowering of gpu.pirntf to a call to printf() (which is what is required for AMD GPUs when using OpenCL) as well as to the hostcall interface present in the AMD Open Compute device library, which is the interface present when kernels are running under HIP.
- Add a "runtime" enum that allows specifying which of the possible runtimes a ROCDL kernel will be executed under or that the runtime is unknown. This enum controls how gpu.printf is lowered
This change does not enable lowering for Nvidia GPUs, but such a lowering should be possible in principle.
And:
[MLIR][AMDGPU] Always set amdgpu-implicitarg-num-bytes=56 on kernels
This is something that Clang always sets on both OpenCL and HIP kernels, and failing to include it causes mysterious crashes with printf() support.
In addition, revert the max-flat-work-group-size to (1, 256) to avoid triggering bugs in the AMDGPU backend.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D110448
NamedAttribute is currently represented as an std::pair, but this
creates an extremely clunky .first/.second API. This commit
converts it to a class, with better accessors (getName/getValue)
and also opens the door for more convenient API in the future.
Differential Revision: https://reviews.llvm.org/D113956
