Files
clang-p2996/mlir/lib/Dialect/Vector/Transforms/LowerVectorInterleave.cpp
Benoit Jacob a1d43c14d8 [mlir][vector] Add Vector-dialect interleave-to-shuffle pattern, enable in VectorToSPIRV (#92012)
This is the second attempt at merging #91800, which bounced due to a
linker error apparently caused by an undeclared dependency.
`MLIRVectorToSPIRV` needed to depend on `MLIRVectorTransforms`. In fact
that was a preexisting issue already flagged by the tool in
https://discourse.llvm.org/t/ninja-can-now-check-for-missing-cmake-dependencies-on-generated-files/74344.

Context: https://github.com/iree-org/iree/issues/17346.

Test IREE integrate showing it's fixing the problem it's intended to
fix, i.e. it allows IREE to drop its local revert of
https://github.com/llvm/llvm-project/pull/89131:

https://github.com/iree-org/iree/pull/17359

This is added to VectorToSPIRV because SPIRV doesn't currently handle
`vector.interleave` (see motivating context above).

This is limited to 1D, non-scalable vectors.
2024-05-13 15:36:28 -04:00

127 lines
4.5 KiB
C++

//===- LowerVectorInterleave.cpp - Lower 'vector.interleave' operation ----===//
//
// 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 target-independent rewrites and utilities to lower the
// 'vector.interleave' operation.
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/Vector/IR/VectorOps.h"
#include "mlir/Dialect/Vector/Transforms/LoweringPatterns.h"
#include "mlir/Dialect/Vector/Utils/VectorUtils.h"
#include "mlir/IR/BuiltinTypes.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/Support/LogicalResult.h"
#define DEBUG_TYPE "vector-interleave-lowering"
using namespace mlir;
using namespace mlir::vector;
namespace {
/// A one-shot unrolling of vector.interleave to the `targetRank`.
///
/// Example:
///
/// ```mlir
/// vector.interleave %a, %b : vector<1x2x3x4xi64>
/// ```
/// Would be unrolled to:
/// ```mlir
/// %result = arith.constant dense<0> : vector<1x2x3x8xi64>
/// %0 = vector.extract %a[0, 0, 0] ─┐
/// : vector<4xi64> from vector<1x2x3x4xi64> |
/// %1 = vector.extract %b[0, 0, 0] |
/// : vector<4xi64> from vector<1x2x3x4xi64> | - Repeated 6x for
/// %2 = vector.interleave %0, %1 : vector<4xi64> | all leading positions
/// %3 = vector.insert %2, %result [0, 0, 0] |
/// : vector<8xi64> into vector<1x2x3x8xi64> ┘
/// ```
///
/// Note: If any leading dimension before the `targetRank` is scalable the
/// unrolling will stop before the scalable dimension.
class UnrollInterleaveOp : public OpRewritePattern<vector::InterleaveOp> {
public:
UnrollInterleaveOp(int64_t targetRank, MLIRContext *context,
PatternBenefit benefit = 1)
: OpRewritePattern(context, benefit), targetRank(targetRank){};
LogicalResult matchAndRewrite(vector::InterleaveOp op,
PatternRewriter &rewriter) const override {
VectorType resultType = op.getResultVectorType();
auto unrollIterator = vector::createUnrollIterator(resultType, targetRank);
if (!unrollIterator)
return failure();
auto loc = op.getLoc();
Value result = rewriter.create<arith::ConstantOp>(
loc, resultType, rewriter.getZeroAttr(resultType));
for (auto position : *unrollIterator) {
Value extractLhs = rewriter.create<ExtractOp>(loc, op.getLhs(), position);
Value extractRhs = rewriter.create<ExtractOp>(loc, op.getRhs(), position);
Value interleave =
rewriter.create<InterleaveOp>(loc, extractLhs, extractRhs);
result = rewriter.create<InsertOp>(loc, interleave, result, position);
}
rewriter.replaceOp(op, result);
return success();
}
private:
int64_t targetRank = 1;
};
/// Rewrite vector.interleave op into an equivalent vector.shuffle op, when
/// applicable: `sourceType` must be 1D and non-scalable.
///
/// Example:
///
/// ```mlir
/// vector.interleave %a, %b : vector<7xi16>
/// ```
///
/// Is rewritten into:
///
/// ```mlir
/// vector.shuffle %arg0, %arg1 [0, 7, 1, 8, 2, 9, 3, 10, 4, 11, 5, 12, 6, 13]
/// : vector<7xi16>, vector<7xi16>
/// ```
class InterleaveToShuffle : public OpRewritePattern<vector::InterleaveOp> {
public:
InterleaveToShuffle(MLIRContext *context, PatternBenefit benefit = 1)
: OpRewritePattern(context, benefit) {};
LogicalResult matchAndRewrite(vector::InterleaveOp op,
PatternRewriter &rewriter) const override {
VectorType sourceType = op.getSourceVectorType();
if (sourceType.getRank() != 1 || sourceType.isScalable()) {
return failure();
}
int64_t n = sourceType.getNumElements();
auto seq = llvm::seq<int64_t>(2 * n);
auto zip = llvm::to_vector(llvm::map_range(
seq, [n](int64_t i) { return (i % 2 ? n : 0) + i / 2; }));
rewriter.replaceOpWithNewOp<ShuffleOp>(op, op.getLhs(), op.getRhs(), zip);
return success();
}
};
} // namespace
void mlir::vector::populateVectorInterleaveLoweringPatterns(
RewritePatternSet &patterns, int64_t targetRank, PatternBenefit benefit) {
patterns.add<UnrollInterleaveOp>(targetRank, patterns.getContext(), benefit);
}
void mlir::vector::populateVectorInterleaveToShufflePatterns(
RewritePatternSet &patterns, PatternBenefit benefit) {
patterns.add<InterleaveToShuffle>(patterns.getContext(), benefit);
}