Files
clang-p2996/mlir/test/lib/Transforms/TestBufferPlacement.cpp
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

259 lines
11 KiB
C++

//===- TestBufferPlacement.cpp - Test for buffer placement ------*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This file implements logic for testing buffer placement including its
// utility converters.
//
//===----------------------------------------------------------------------===//
#include "TestDialect.h"
#include "mlir/Conversion/StandardToLLVM/ConvertStandardToLLVM.h"
#include "mlir/Dialect/Linalg/IR/LinalgOps.h"
#include "mlir/IR/Function.h"
#include "mlir/IR/Operation.h"
#include "mlir/Pass/Pass.h"
#include "mlir/Pass/PassManager.h"
#include "mlir/Transforms/Bufferize.h"
using namespace mlir;
namespace {
/// This pass tests the computeAllocPosition helper method and bufferize
/// operation converters. Furthermore, this pass converts linalg operations on
/// tensors to linalg operations on buffers to prepare them for the
/// BufferPlacement pass that can be applied afterwards.
/// `allowMemrefFunctionResults` informs the buffer placement to allow functions
/// that have memref typed results. Buffer assignment operation converters will
/// be adapted respectively. It will also allow memref typed results to escape
/// from the deallocation.
template <bool allowMemrefFunctionResults>
struct TestBufferPlacementPreparationPass
: mlir::PassWrapper<
TestBufferPlacementPreparationPass<allowMemrefFunctionResults>,
OperationPass<ModuleOp>> {
/// Converts tensor-type generic linalg operations to memref ones using
/// bufferize.
/// TODO: Avoid the copy-pasta by exposing the pattern from BufferPlacement.h
/// This is limited by not wanting BufferPlacement to depend on Linalg. Fixing
/// this probably requires an OpConversionPattern over generic Operation*. For
/// now only RewritePattern but not ConversionPattern allow this.
class GenericOpConverter
: public BufferizeOpConversionPattern<linalg::GenericOp> {
public:
using BufferizeOpConversionPattern<
linalg::GenericOp>::BufferizeOpConversionPattern;
LogicalResult
matchAndRewrite(linalg::GenericOp op, ArrayRef<Value> operands,
ConversionPatternRewriter &rewriter) const final {
linalg::GenericOpAdaptor adaptor(operands,
op.getOperation()->getAttrDictionary());
// All inputs need to be turned into buffers first. Until then, bail out.
if (llvm::any_of(adaptor.inputs(), [](Value in) {
return !in.getType().isa<MemRefType>();
}))
return failure();
// All init_tensors need to be turned into buffers first. Until then, bail
// out.
if (llvm::any_of(adaptor.init_tensors(), [](Value in) {
return !in.getType().isa<MemRefType>();
}))
return failure();
Location loc = op.getLoc();
SmallVector<Value, 2> newOutputBuffers;
newOutputBuffers.reserve(op.getNumOutputs());
newOutputBuffers.append(adaptor.output_buffers().begin(),
adaptor.output_buffers().end());
// Update all types to memref types.
// Assume the init tensors fold onto the first results.
// TODO: update this assumption because the reality is more complex under
// linalg on tensor based transformations.
for (auto en : llvm::enumerate(op.getResultTypes())) {
auto type = en.value().cast<ShapedType>();
if (!type.hasStaticShape())
return rewriter.notifyMatchFailure(
op, "dynamic shapes not currently supported");
auto memrefType =
MemRefType::get(type.getShape(), type.getElementType());
bool foldedInitTensor = en.index() < op.getNumInitTensors();
if (foldedInitTensor) {
// Dealing with an init tensor requires distinguishing between 1-use
// and many-use cases which would create aliasing and WAR hazards.
Value initTensor = op.getInitTensor(en.index());
Value initBuffer = adaptor.init_tensors()[en.index()];
if (initTensor.hasOneUse()) {
newOutputBuffers.push_back(initBuffer);
continue;
}
auto alloc = rewriter.create<AllocOp>(loc, memrefType);
rewriter.create<linalg::CopyOp>(loc, initBuffer, alloc);
newOutputBuffers.push_back(alloc);
} else {
auto alloc = rewriter.create<AllocOp>(loc, memrefType);
newOutputBuffers.push_back(alloc);
}
}
// Generate a new linalg operation that works on buffers.
auto linalgOp = rewriter.create<linalg::GenericOp>(
loc,
/*resultTensorTypes=*/ArrayRef<Type>{},
/*inputs=*/adaptor.inputs(),
/*outputBuffers=*/newOutputBuffers,
/*initTensors=*/ValueRange{}, op.indexing_maps(), op.iterator_types(),
op.docAttr(), op.library_callAttr(), op.symbol_sourceAttr());
// Create a new block in the region of the new Generic Op.
Block &oldBlock = op.getRegion().front();
Region &newRegion = linalgOp.region();
Block *newBlock = rewriter.createBlock(&newRegion, newRegion.begin(),
oldBlock.getArgumentTypes());
// Add the result arguments that do not come from init_tensors to the new
// block.
// TODO: update this assumption because the reality is more complex under
// linalg on tensor based transformations.
for (Value v : ValueRange(newOutputBuffers)
.drop_front(adaptor.init_tensors().size()))
newBlock->addArgument(v.getType().cast<MemRefType>().getElementType());
// Clone the body of the old block to the new block.
BlockAndValueMapping mapping;
for (unsigned i = 0; i < oldBlock.getNumArguments(); i++)
mapping.map(oldBlock.getArgument(i), newBlock->getArgument(i));
OpBuilder::InsertionGuard guard(rewriter);
rewriter.setInsertionPointToEnd(newBlock);
for (auto &op : oldBlock.getOperations()) {
Operation *clonedOp = rewriter.clone(op, mapping);
mapping.map(op.getResults(), clonedOp->getResults());
}
// Replace the results of the old op with the new output buffers.
rewriter.replaceOp(op, newOutputBuffers);
return success();
}
};
void populateTensorLinalgToBufferLinalgConversionPattern(
MLIRContext *context, BufferizeTypeConverter &converter,
OwningRewritePatternList &patterns) {
populateWithBufferizeOpConversionPatterns<mlir::ReturnOp, mlir::ReturnOp,
linalg::CopyOp>(
context, converter, patterns);
patterns.insert<GenericOpConverter>(context, converter);
}
void getDependentDialects(DialectRegistry &registry) const override {
registry.insert<TestDialect>();
registry.insert<linalg::LinalgDialect>();
}
void runOnOperation() override {
MLIRContext &context = this->getContext();
ConversionTarget target(context);
BufferizeTypeConverter converter;
// Mark all Standard operations legal.
target.addLegalDialect<StandardOpsDialect>();
target.addLegalOp<MakeTupleOp>();
target.addLegalOp<GetTupleElementOp>();
target.addLegalOp<ModuleOp>();
target.addLegalOp<ModuleTerminatorOp>();
// Mark all Linalg operations illegal as long as they work on tensors.
auto isLegalOperation = [&](Operation *op) {
return converter.isLegal(op);
};
target.addDynamicallyLegalDialect<linalg::LinalgDialect>(isLegalOperation);
// Mark Standard Return operations illegal as long as one operand is tensor.
target.addDynamicallyLegalOp<mlir::ReturnOp>([&](mlir::ReturnOp returnOp) {
return converter.isLegal(returnOp.getOperandTypes());
});
// Mark Standard Call Operation illegal as long as it operates on tensor.
target.addDynamicallyLegalOp<mlir::CallOp>(
[&](mlir::CallOp callOp) { return converter.isLegal(callOp); });
// Mark the function whose arguments are in tensor-type illegal.
target.addDynamicallyLegalOp<FuncOp>([&](FuncOp funcOp) {
return converter.isSignatureLegal(funcOp.getType()) &&
converter.isLegal(&funcOp.getBody());
});
auto kind = allowMemrefFunctionResults
? BufferizeTypeConverter::KeepAsFunctionResult
: BufferizeTypeConverter::AppendToArgumentsList;
converter.setResultConversionKind<RankedTensorType, MemRefType>(kind);
converter.setResultConversionKind<UnrankedTensorType, UnrankedMemRefType>(
kind);
converter.addDecomposeTypeConversion(
[](TupleType tupleType, SmallVectorImpl<Type> &types) {
tupleType.getFlattenedTypes(types);
return success();
});
converter.addArgumentMaterialization(
[](OpBuilder &builder, TupleType resultType, ValueRange inputs,
Location loc) -> Optional<Value> {
if (inputs.size() == 1)
return llvm::None;
TypeRange TypeRange = inputs.getTypes();
SmallVector<Type, 2> types(TypeRange.begin(), TypeRange.end());
TupleType tuple = TupleType::get(types, builder.getContext());
mlir::Value value = builder.create<MakeTupleOp>(loc, tuple, inputs);
return value;
});
converter.addDecomposeValueConversion([](OpBuilder &builder, Location loc,
TupleType resultType, Value value,
SmallVectorImpl<Value> &values) {
for (unsigned i = 0, e = resultType.size(); i < e; ++i) {
Value res = builder.create<GetTupleElementOp>(
loc, resultType.getType(i), value, builder.getI32IntegerAttr(i));
values.push_back(res);
}
return success();
});
OwningRewritePatternList patterns;
populateTensorLinalgToBufferLinalgConversionPattern(&context, converter,
patterns);
if (failed(applyFullConversion(this->getOperation(), target,
std::move(patterns))))
this->signalPassFailure();
};
};
} // end anonymous namespace
namespace mlir {
void registerTestBufferPlacementPreparationPass() {
PassRegistration<
TestBufferPlacementPreparationPass</*allowMemrefFunctionResults=*/false>>(
"test-buffer-placement-preparation",
"Tests buffer placement helper methods including its "
"operation-conversion patterns");
}
void registerTestPreparationPassWithAllowedMemrefResults() {
PassRegistration<
TestBufferPlacementPreparationPass</*allowMemrefFunctionResults=*/true>>(
"test-buffer-placement-preparation-with-allowed-memref-results",
"Tests the helper operation converters of buffer placement for allowing "
"functions to have memref typed results.");
}
} // end namespace mlir