llvm/mlir/lib/Analysis/AliasAnalysis/LocalAliasAnalysis.cpp

//===- LocalAliasAnalysis.cpp - Local stateless alias Analysis for MLIR ---===//
//
// 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
//
//===----------------------------------------------------------------------===//

#include "mlir/Analysis/AliasAnalysis/LocalAliasAnalysis.h"

#include "mlir/Analysis/AliasAnalysis.h"
#include "mlir/IR/Attributes.h"
#include "mlir/IR/Block.h"
#include "mlir/IR/Matchers.h"
#include "mlir/IR/OpDefinition.h"
#include "mlir/IR/Operation.h"
#include "mlir/IR/Region.h"
#include "mlir/IR/Value.h"
#include "mlir/IR/ValueRange.h"
#include "mlir/Interfaces/ControlFlowInterfaces.h"
#include "mlir/Interfaces/FunctionInterfaces.h"
#include "mlir/Interfaces/SideEffectInterfaces.h"
#include "mlir/Interfaces/ViewLikeInterface.h"
#include "mlir/Support/LLVM.h"
#include "llvm/Support/Casting.h"
#include <cassert>
#include <optional>
#include <utility>

usingnamespacemlir;

//===----------------------------------------------------------------------===//
// Underlying Address Computation
//===----------------------------------------------------------------------===//

/// The maximum depth that will be searched when trying to find an underlying
/// value.
static constexpr unsigned maxUnderlyingValueSearchDepth = …;

/// Given a value, collect all of the underlying values being addressed.
static void collectUnderlyingAddressValues(Value value, unsigned maxDepth,
                                           DenseSet<Value> &visited,
                                           SmallVectorImpl<Value> &output);

/// Given a successor (`region`) of a RegionBranchOpInterface, collect all of
/// the underlying values being addressed by one of the successor inputs. If the
/// provided `region` is null, as per `RegionBranchOpInterface` this represents
/// the parent operation.
static void collectUnderlyingAddressValues(RegionBranchOpInterface branch,
                                           Region *region, Value inputValue,
                                           unsigned inputIndex,
                                           unsigned maxDepth,
                                           DenseSet<Value> &visited,
                                           SmallVectorImpl<Value> &output) { … }

/// Given a result, collect all of the underlying values being addressed.
static void collectUnderlyingAddressValues(OpResult result, unsigned maxDepth,
                                           DenseSet<Value> &visited,
                                           SmallVectorImpl<Value> &output) { … }

/// Given a block argument, collect all of the underlying values being
/// addressed.
static void collectUnderlyingAddressValues(BlockArgument arg, unsigned maxDepth,
                                           DenseSet<Value> &visited,
                                           SmallVectorImpl<Value> &output) { … }

/// Given a value, collect all of the underlying values being addressed.
static void collectUnderlyingAddressValues(Value value, unsigned maxDepth,
                                           DenseSet<Value> &visited,
                                           SmallVectorImpl<Value> &output) { … }

/// Given a value, collect all of the underlying values being addressed.
static void collectUnderlyingAddressValues(Value value,
                                           SmallVectorImpl<Value> &output) { … }

//===----------------------------------------------------------------------===//
// LocalAliasAnalysis: alias
//===----------------------------------------------------------------------===//

/// Given a value, try to get an allocation effect attached to it. If
/// successful, `allocEffect` is populated with the effect. If an effect was
/// found, `allocScopeOp` is also specified if a parent operation of `value`
/// could be identified that bounds the scope of the allocated value; i.e. if
/// non-null it specifies the parent operation that the allocation does not
/// escape. If no scope is found, `allocScopeOp` is set to nullptr.
static LogicalResult
getAllocEffectFor(Value value,
                  std::optional<MemoryEffects::EffectInstance> &effect,
                  Operation *&allocScopeOp) { … }

/// Given the two values, return their aliasing behavior.
AliasResult LocalAliasAnalysis::aliasImpl(Value lhs, Value rhs) { … }

/// Given the two values, return their aliasing behavior.
AliasResult LocalAliasAnalysis::alias(Value lhs, Value rhs) { … }

//===----------------------------------------------------------------------===//
// LocalAliasAnalysis: getModRef
//===----------------------------------------------------------------------===//

ModRefResult LocalAliasAnalysis::getModRef(Operation *op, Value location) { … }