llvm-project/mlir/lib/Dialect/Linalg/Transforms/InlineScalarOperands.cpp
River Riddle 4157455425 [mlir][Pass] Deprecate FunctionPass in favor of OperationPass<FuncOp>
The only benefit of FunctionPass is that it filters out function
declarations. This isn't enough to justify carrying it around, as we can
simplify filter out declarations when necessary within the pass. We can
also explore with better scheduling primitives to filter out declarations
at the pipeline level in the future.

The definition of FunctionPass is left intact for now to allow time for downstream
users to migrate.

Differential Revision: https://reviews.llvm.org/D117182
2022-01-18 19:52:44 -08:00

115 lines
4.2 KiB
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//===- InlineScalarOperands.cpp - Pass to inline scalar operands =============//
//
// 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 patterns/pass to inline scalar operands into a generic
// operation. A scalar operand is an operand whose indexing map has a constant
// rhs.
//
//===----------------------------------------------------------------------===//
#include "PassDetail.h"
#include "mlir/Dialect/Arithmetic/IR/Arithmetic.h"
#include "mlir/Dialect/Linalg/IR/Linalg.h"
#include "mlir/Dialect/Linalg/Passes.h"
#include "mlir/Dialect/Linalg/Transforms/Transforms.h"
#include "mlir/IR/AffineExpr.h"
#include "mlir/IR/AffineMap.h"
#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
using namespace mlir;
using namespace mlir::linalg;
namespace {
struct InlineScalarOperands : public OpRewritePattern<GenericOp> {
using OpRewritePattern<GenericOp>::OpRewritePattern;
LogicalResult matchAndRewrite(GenericOp genericOp,
PatternRewriter &rewriter) const override {
if (!genericOp.hasTensorSemantics())
return failure();
SmallVector<size_t> scalarOperands;
SmallVector<AffineMap> newIndexingMaps;
SmallVector<Value> newOperands;
for (OpOperand *opOperand : genericOp.getInputOperands()) {
AffineMap map = genericOp.getTiedIndexingMap(opOperand);
if (genericOp.isInputTensor(opOperand) && map.isConstant()) {
scalarOperands.emplace_back(opOperand->getOperandNumber());
} else {
newIndexingMaps.emplace_back(map);
newOperands.emplace_back(opOperand->get());
}
}
if (scalarOperands.empty())
return failure();
for (OpOperand *opOperand : genericOp.getOutputOperands())
newIndexingMaps.emplace_back(genericOp.getTiedIndexingMap(opOperand));
Location loc = genericOp->getLoc();
SmallVector<Value> outputOperands = genericOp.getOutputOperands();
auto newOp = rewriter.create<GenericOp>(
loc, genericOp->getResultTypes(), newOperands, outputOperands,
newIndexingMaps,
llvm::to_vector<4>(
genericOp.iterator_types().template getAsValueRange<StringAttr>()));
rewriter.cloneRegionBefore(genericOp.region(), newOp.region(),
newOp.region().begin());
Block *body = newOp.getBody();
PatternRewriter::InsertionGuard guard(rewriter);
rewriter.setInsertionPointToStart(body);
for (auto idx : llvm::reverse(scalarOperands)) {
OpOperand *opOperand = genericOp.getInputOperand(idx);
AffineMap map = genericOp.getTiedIndexingMap(opOperand);
SmallVector<int64_t> indices = map.getConstantResults();
SmallVector<Value> indicesValues;
for (auto idx : indices)
indicesValues.emplace_back(
rewriter.create<arith::ConstantIndexOp>(loc, idx));
Value extractedValue = rewriter.create<tensor::ExtractOp>(
loc, opOperand->get(), indicesValues);
body->getArgument(idx).replaceAllUsesWith(extractedValue);
body->eraseArgument(idx);
}
rewriter.replaceOp(genericOp, newOp->getResults());
return success();
}
};
} // namespace
/// Patterns that are used to inline constant operands into linalg generic
/// ops.
void mlir::linalg::populateInlineConstantOperandsPatterns(
RewritePatternSet &patterns) {
auto *context = patterns.getContext();
patterns.add<InlineScalarOperands>(context);
}
namespace {
/// Pass that removes unit-extent dims within generic ops.
struct LinalgInlineScalarOperandsPass
: public LinalgInlineScalarOperandsBase<LinalgInlineScalarOperandsPass> {
void runOnOperation() override {
FuncOp funcOp = getOperation();
MLIRContext *context = funcOp.getContext();
RewritePatternSet patterns(context);
populateInlineConstantOperandsPatterns(patterns);
(void)applyPatternsAndFoldGreedily(funcOp.getBody(), std::move(patterns));
}
};
} // namespace
std::unique_ptr<OperationPass<FuncOp>>
mlir::createLinalgInlineScalarOperandsPass() {
return std::make_unique<LinalgInlineScalarOperandsPass>();
}