Files
clang-p2996/mlir/lib/Dialect/Tosa/Transforms/TosaFoldConstantTranspose.cpp
Jacques Pienaar b1f2e2664e [mlir][tosa] Switch TosaFoldConstantTranspose to use ElementsAttr.
Also avoid redoing index calculation.

Differential Revision: https://reviews.llvm.org/D132274
2022-08-22 15:45:23 -07:00

91 lines
3.3 KiB
C++

//===- TosaFoldConstantTranspose.cpp --------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Fold TOSA Transpose operation on constant data
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/Tosa/IR/TosaOps.h"
#include "mlir/Dialect/Tosa/Transforms/Passes.h"
#include "mlir/IR/Matchers.h"
#include "mlir/Pass/Pass.h"
using namespace mlir;
using namespace mlir::tosa;
namespace {
struct TosaFoldConstantTranspose : public OpRewritePattern<tosa::TransposeOp> {
using OpRewritePattern::OpRewritePattern;
LogicalResult matchAndRewrite(tosa::TransposeOp op,
PatternRewriter &rewriter) const override {
auto outputType = op.getType().cast<ShapedType>();
// TOSA supports quantized types.
if (!outputType.getElementType().isIntOrIndexOrFloat())
return failure();
ElementsAttr inputValues;
if (!matchPattern(op.getInput1(), m_Constant(&inputValues)))
return failure();
// Make sure the input is a constant that has a single user.
if (!llvm::hasSingleElement(op.getInput1().getDefiningOp()->getUsers()))
return failure();
DenseIntElementsAttr permAttr;
if (!matchPattern(op.getPerms(), m_Constant(&permAttr)))
return failure();
auto permValues = llvm::to_vector<6>(llvm::map_range(
// TOSA allows both 32- and 64-bit integer tensors here.
permAttr.getValues<APInt>(),
[](const APInt &val) { return val.getZExtValue(); }));
auto inputType = op.getInput1().getType().cast<ShapedType>();
ArrayRef<int64_t> inputShape = inputType.getShape();
int64_t numElements = inputType.getNumElements();
SmallVector<Attribute, 4> outputValues;
outputValues.resize(numElements);
// Transpose the input constant. Because we don't know its rank in advance,
// we need to loop over the range [0, element count) and delinearize the
// index.
auto attrValues = inputValues.getValues<Attribute>();
ArrayRef<int64_t> outputShape = outputType.getShape();
for (const auto &it : llvm::enumerate(attrValues)) {
SmallVector<uint64_t, 6> srcIndices(inputType.getRank(), 0);
int totalCount = it.index();
for (int dim = inputType.getRank() - 1; dim >= 0; --dim) {
srcIndices[dim] = totalCount % inputShape[dim];
totalCount /= inputShape[dim];
}
SmallVector<uint64_t, 6> dstIndices(outputType.getRank(), 0);
for (int dim = outputType.getRank() - 1; dim >= 0; --dim)
dstIndices[dim] = srcIndices[permValues[dim]];
uint64_t dstLinearIndex = dstIndices.front();
for (int dim = 1; dim < outputType.getRank(); ++dim)
dstLinearIndex = dstLinearIndex * outputShape[dim] + dstIndices[dim];
outputValues[dstLinearIndex] = it.value();
}
rewriter.replaceOpWithNewOp<tosa::ConstOp>(
op, outputType, DenseElementsAttr::get(outputType, outputValues));
return success();
}
};
} // namespace
void mlir::tosa::populateTosaFoldConstantTransposePatterns(
MLIRContext *ctx, RewritePatternSet &patterns) {
patterns.add<TosaFoldConstantTranspose>(ctx);
}