llvm/llvm/lib/Transforms/Utils/AssumeBundleBuilder.cpp

//===- AssumeBundleBuilder.cpp - tools to preserve informations -*- C++ -*-===//
//
// 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 "llvm/Transforms/Utils/AssumeBundleBuilder.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AssumeBundleQueries.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/DebugCounter.h"
#include "llvm/Transforms/Utils/Local.h"

usingnamespacellvm;

namespace llvm {
cl::opt<bool> ShouldPreserveAllAttributes(
    "assume-preserve-all", cl::init(false), cl::Hidden,
    cl::desc("enable preservation of all attrbitues. even those that are "
             "unlikely to be usefull"));

cl::opt<bool> EnableKnowledgeRetention(
    "enable-knowledge-retention", cl::init(false), cl::Hidden,
    cl::desc(
        "enable preservation of attributes throughout code transformation"));
} // namespace llvm

#define DEBUG_TYPE …

STATISTIC(NumAssumeBuilt, "Number of assume built by the assume builder");
STATISTIC(NumBundlesInAssumes, "Total number of Bundles in the assume built");
STATISTIC(NumAssumesMerged,
          "Number of assume merged by the assume simplify pass");
STATISTIC(NumAssumesRemoved,
          "Number of assume removed by the assume simplify pass");

DEBUG_COUNTER(BuildAssumeCounter, "assume-builder-counter",
              "Controls which assumes gets created");

namespace {

bool isUsefullToPreserve(Attribute::AttrKind Kind) { … }

/// This function will try to transform the given knowledge into a more
/// canonical one. the canonical knowledge maybe the given one.
RetainedKnowledge canonicalizedKnowledge(RetainedKnowledge RK,
                                         const DataLayout &DL) { … }

/// This class contain all knowledge that have been gather while building an
/// llvm.assume and the function to manipulate it.
struct AssumeBuilderState { … };

} // namespace

AssumeInst *llvm::buildAssumeFromInst(Instruction *I) { … }

bool llvm::salvageKnowledge(Instruction *I, AssumptionCache *AC,
                            DominatorTree *DT) { … }

AssumeInst *
llvm::buildAssumeFromKnowledge(ArrayRef<RetainedKnowledge> Knowledge,
                               Instruction *CtxI, AssumptionCache *AC,
                               DominatorTree *DT) { … }

RetainedKnowledge llvm::simplifyRetainedKnowledge(AssumeInst *Assume,
                                                  RetainedKnowledge RK,
                                                  AssumptionCache *AC,
                                                  DominatorTree *DT) { … }

namespace {

struct AssumeSimplify { … };

bool simplifyAssumes(Function &F, AssumptionCache *AC, DominatorTree *DT) { … }

} // namespace

PreservedAnalyses AssumeSimplifyPass::run(Function &F,
                                          FunctionAnalysisManager &AM) { … }

PreservedAnalyses AssumeBuilderPass::run(Function &F,
                                         FunctionAnalysisManager &AM) { … }