llvm/mlir/lib/Transforms/CSE.cpp

//===- CSE.cpp - Common Sub-expression Elimination ------------------------===//
//
// 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 transformation pass performs a simple common sub-expression elimination
// algorithm on operations within a region.
//
//===----------------------------------------------------------------------===//

#include "mlir/Transforms/CSE.h"

#include "mlir/IR/Dominance.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/Interfaces/SideEffectInterfaces.h"
#include "mlir/Pass/Pass.h"
#include "mlir/Transforms/Passes.h"
#include "llvm/ADT/DenseMapInfo.h"
#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/ScopedHashTable.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/RecyclingAllocator.h"
#include <deque>

namespace mlir {
#define GEN_PASS_DEF_CSE
#include "mlir/Transforms/Passes.h.inc"
} // namespace mlir

usingnamespacemlir;

namespace {
struct SimpleOperationInfo : public llvm::DenseMapInfo<Operation *> { … };
} // namespace

namespace {
/// Simple common sub-expression elimination.
class CSEDriver { … };
} // namespace

void CSEDriver::replaceUsesAndDelete(ScopedMapTy &knownValues, Operation *op,
                                     Operation *existing,
                                     bool hasSSADominance) { … }

bool CSEDriver::hasOtherSideEffectingOpInBetween(Operation *fromOp,
                                                 Operation *toOp) { … }

/// Attempt to eliminate a redundant operation.
LogicalResult CSEDriver::simplifyOperation(ScopedMapTy &knownValues,
                                           Operation *op,
                                           bool hasSSADominance) { … }

void CSEDriver::simplifyBlock(ScopedMapTy &knownValues, Block *bb,
                              bool hasSSADominance) { … }

void CSEDriver::simplifyRegion(ScopedMapTy &knownValues, Region &region) { … }

void CSEDriver::simplify(Operation *op, bool *changed) { … }

void mlir::eliminateCommonSubExpressions(RewriterBase &rewriter,
                                         DominanceInfo &domInfo, Operation *op,
                                         bool *changed) { … }

namespace {
/// CSE pass.
struct CSE : public impl::CSEBase<CSE> { … };
} // namespace

void CSE::runOnOperation() { … }

std::unique_ptr<Pass> mlir::createCSEPass() { … }