llvm-project/mlir/lib/Transforms/LoopInvariantCodeMotion.cpp
Kazu Hirata b5cd49eff0
[mlir] Remove unused includes (NFC) (#146278)
These are identified by misc-include-cleaner.  I've filtered out those
that break builds.  Also, I'm staying away from llvm-config.h,
config.h, and Compiler.h, which likely cause platform- or
compiler-specific build failures.
2025-06-29 12:13:12 -07:00

66 lines
2.3 KiB
C++

//===- LoopInvariantCodeMotion.cpp - Code to perform loop fusion-----------===//
//
// 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 loop invariant code motion.
//
//===----------------------------------------------------------------------===//
#include "mlir/Transforms/Passes.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/Interfaces/LoopLikeInterface.h"
#include "mlir/Transforms/LoopInvariantCodeMotionUtils.h"
namespace mlir {
#define GEN_PASS_DEF_LOOPINVARIANTCODEMOTION
#define GEN_PASS_DEF_LOOPINVARIANTSUBSETHOISTING
#include "mlir/Transforms/Passes.h.inc"
} // namespace mlir
using namespace mlir;
namespace {
/// Loop invariant code motion (LICM) pass.
struct LoopInvariantCodeMotion
: public impl::LoopInvariantCodeMotionBase<LoopInvariantCodeMotion> {
void runOnOperation() override;
};
struct LoopInvariantSubsetHoisting
: public impl::LoopInvariantSubsetHoistingBase<
LoopInvariantSubsetHoisting> {
void runOnOperation() override;
};
} // namespace
void LoopInvariantCodeMotion::runOnOperation() {
// Walk through all loops in a function in innermost-loop-first order. This
// way, we first LICM from the inner loop, and place the ops in
// the outer loop, which in turn can be further LICM'ed.
getOperation()->walk(
[&](LoopLikeOpInterface loopLike) { moveLoopInvariantCode(loopLike); });
}
void LoopInvariantSubsetHoisting::runOnOperation() {
IRRewriter rewriter(getOperation()->getContext());
// Walk through all loops in a function in innermost-loop-first order. This
// way, we first hoist from the inner loop, and place the ops in the outer
// loop, which in turn can be further hoisted from.
getOperation()->walk([&](LoopLikeOpInterface loopLike) {
(void)hoistLoopInvariantSubsets(rewriter, loopLike);
});
}
std::unique_ptr<Pass> mlir::createLoopInvariantCodeMotionPass() {
return std::make_unique<LoopInvariantCodeMotion>();
}
std::unique_ptr<Pass> mlir::createLoopInvariantSubsetHoistingPass() {
return std::make_unique<LoopInvariantSubsetHoisting>();
}