llvm-project/mlir/lib/Dialect/Bufferization/TransformOps/BufferizationTransformOps.cpp
Martin Erhart 6a91dfedeb [mlir][bufferization] Remove allow-return-allocs and create-deallocs pass options, remove bufferization.escape attribute
This is the first commit in a series with the goal to rework the
BufferDeallocation pass. Currently, this pass heavily relies on copies
to perform correct deallocations, which leads to very slow code and
potentially high memory usage. Additionally, there are unsupported cases
such as returning memrefs which this series of commits aims to add
support for as well.

This first commit removes the deallocation capabilities of
one-shot-bufferization.One-shot-bufferization should never deallocate any
memrefs as this should be entirely handled by the buffer-deallocation pass
going forward. This means the allow-return-allocs pass option will
default to true now, create-deallocs defaults to false and they, as well
as the escape attribute indicating whether a memref escapes the current region,
will be removed.

The documentation should w.r.t. these pass option changes should also be
updated in this commit.

Reviewed By: springerm

Differential Revision: https://reviews.llvm.org/D156662
2023-09-13 09:30:22 +00:00

178 lines
7.1 KiB
C++

//===- BufferizationTransformOps.h - Bufferization transform ops ----------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/Bufferization/TransformOps/BufferizationTransformOps.h"
#include "mlir/Dialect/Bufferization/IR/Bufferization.h"
#include "mlir/Dialect/Bufferization/Transforms/OneShotAnalysis.h"
#include "mlir/Dialect/Bufferization/Transforms/OneShotModuleBufferize.h"
#include "mlir/Dialect/Bufferization/Transforms/Passes.h"
#include "mlir/Dialect/Bufferization/Transforms/Transforms.h"
#include "mlir/Dialect/Linalg/IR/Linalg.h"
#include "mlir/Dialect/MemRef/IR/MemRef.h"
#include "mlir/Dialect/Tensor/IR/Tensor.h"
#include "mlir/Dialect/Transform/IR/TransformDialect.h"
#include "mlir/Interfaces/FunctionInterfaces.h"
using namespace mlir;
using namespace mlir::bufferization;
using namespace mlir::transform;
//===----------------------------------------------------------------------===//
// BufferLoopHoistingOp
//===----------------------------------------------------------------------===//
DiagnosedSilenceableFailure transform::BufferLoopHoistingOp::applyToOne(
TransformRewriter &rewriter, Operation *target,
ApplyToEachResultList &results, TransformState &state) {
bufferization::hoistBuffersFromLoops(target);
return DiagnosedSilenceableFailure::success();
}
void transform::BufferLoopHoistingOp::getEffects(
SmallVectorImpl<MemoryEffects::EffectInstance> &effects) {
onlyReadsHandle(getTarget(), effects);
modifiesPayload(effects);
}
//===----------------------------------------------------------------------===//
// OneShotBufferizeOp
//===----------------------------------------------------------------------===//
LogicalResult transform::OneShotBufferizeOp::verify() {
if (getMemcpyOp() != "memref.copy" && getMemcpyOp() != "linalg.copy")
return emitOpError() << "unsupported memcpy op";
return success();
}
DiagnosedSilenceableFailure
transform::OneShotBufferizeOp::apply(transform::TransformRewriter &rewriter,
TransformResults &transformResults,
TransformState &state) {
OneShotBufferizationOptions options;
options.allowUnknownOps = getAllowUnknownOps();
options.bufferizeFunctionBoundaries = getBufferizeFunctionBoundaries();
options.testAnalysisOnly = getTestAnalysisOnly();
options.printConflicts = getPrintConflicts();
if (getFunctionBoundaryTypeConversion().has_value())
options.setFunctionBoundaryTypeConversion(
*getFunctionBoundaryTypeConversion());
if (getMemcpyOp() == "memref.copy") {
options.memCpyFn = [](OpBuilder &b, Location loc, Value from, Value to) {
b.create<memref::CopyOp>(loc, from, to);
return success();
};
} else if (getMemcpyOp() == "linalg.copy") {
options.memCpyFn = [](OpBuilder &b, Location loc, Value from, Value to) {
b.create<linalg::CopyOp>(loc, from, to);
return success();
};
} else {
llvm_unreachable("invalid copy op");
}
auto payloadOps = state.getPayloadOps(getTarget());
for (Operation *target : payloadOps) {
if (!isa<ModuleOp, FunctionOpInterface>(target))
return emitSilenceableError() << "expected module or function target";
auto moduleOp = dyn_cast<ModuleOp>(target);
if (options.bufferizeFunctionBoundaries) {
if (!moduleOp)
return emitSilenceableError() << "expected module target";
if (failed(bufferization::runOneShotModuleBufferize(moduleOp, options)))
return emitSilenceableError() << "bufferization failed";
} else {
if (failed(bufferization::runOneShotBufferize(target, options)))
return emitSilenceableError() << "bufferization failed";
}
}
// This transform op is currently restricted to ModuleOps and function ops.
// Such ops are modified in-place.
transformResults.set(cast<OpResult>(getTransformed()), payloadOps);
return DiagnosedSilenceableFailure::success();
}
//===----------------------------------------------------------------------===//
// EliminateEmptyTensorsOp
//===----------------------------------------------------------------------===//
void transform::EliminateEmptyTensorsOp::getEffects(
SmallVectorImpl<MemoryEffects::EffectInstance> &effects) {
onlyReadsHandle(getTarget(), effects);
modifiesPayload(effects);
}
DiagnosedSilenceableFailure transform::EliminateEmptyTensorsOp::apply(
transform::TransformRewriter &rewriter, TransformResults &transformResults,
TransformState &state) {
OneShotBufferizationOptions options;
for (Operation *target : state.getPayloadOps(getTarget())) {
OneShotAnalysisState state(target, options);
if (failed(analyzeOp(target, state)))
return mlir::emitSilenceableFailure(target->getLoc())
<< "failed to analyze op";
if (failed(bufferization::insertSliceAnchoredEmptyTensorEliminationStep(
rewriter, target, state)))
return mlir::emitSilenceableFailure(target->getLoc())
<< "failed to eliminate insert_slice anchored tensor.empty ops";
}
return DiagnosedSilenceableFailure::success();
}
//===----------------------------------------------------------------------===//
// EmptyTensorToAllocTensorOp
//===----------------------------------------------------------------------===//
DiagnosedSilenceableFailure EmptyTensorToAllocTensorOp::applyToOne(
transform::TransformRewriter &rewriter, tensor::EmptyOp target,
ApplyToEachResultList &results, transform::TransformState &state) {
rewriter.setInsertionPoint(target);
auto alloc = rewriter.replaceOpWithNewOp<bufferization::AllocTensorOp>(
target, target.getType(), target.getDynamicSizes());
results.push_back(alloc);
return DiagnosedSilenceableFailure::success();
}
//===----------------------------------------------------------------------===//
// Transform op registration
//===----------------------------------------------------------------------===//
namespace {
/// Registers new ops and declares PDL as dependent dialect since the additional
/// ops are using PDL types for operands and results.
class BufferizationTransformDialectExtension
: public transform::TransformDialectExtension<
BufferizationTransformDialectExtension> {
public:
using Base::Base;
void init() {
declareGeneratedDialect<bufferization::BufferizationDialect>();
declareGeneratedDialect<memref::MemRefDialect>();
registerTransformOps<
#define GET_OP_LIST
#include "mlir/Dialect/Bufferization/TransformOps/BufferizationTransformOps.cpp.inc"
>();
}
};
} // namespace
#define GET_OP_CLASSES
#include "mlir/Dialect/Bufferization/TransformOps/BufferizationTransformOps.cpp.inc"
#include "mlir/Dialect/Bufferization/IR/BufferizationEnums.cpp.inc"
void mlir::bufferization::registerTransformDialectExtension(
DialectRegistry &registry) {
registry.addExtensions<BufferizationTransformDialectExtension>();
bufferization::registerAllocationOpInterfaceExternalModels(registry);
}