//===-- Logger.cpp --------------------------------------------------------===//

//

// 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 "clang/Analysis/FlowSensitive/Logger.h"

#include "clang/Analysis/FlowSensitive/ControlFlowContext.h"

#include "clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h"

#include "llvm/Support/WithColor.h"

namespace clang::dataflow {

Logger &Logger::null() {

  struct NullLogger final : Logger {};

  static auto *Instance = new NullLogger();

  return *Instance;

}

namespace {

struct TextualLogger final : Logger {

  llvm::raw_ostream &OS;

  const CFG *CurrentCFG;

  const CFGBlock *CurrentBlock;

  const CFGElement *CurrentElement;

  unsigned CurrentElementIndex;

  bool ShowColors;

  llvm::DenseMap<const CFGBlock *, unsigned> VisitCount;

  TypeErasedDataflowAnalysis *CurrentAnalysis;

  TextualLogger(llvm::raw_ostream &OS)

      : OS(OS), ShowColors(llvm::WithColor::defaultAutoDetectFunction()(OS)) {}

  virtual void beginAnalysis(const ControlFlowContext &CFG,

                             TypeErasedDataflowAnalysis &Analysis) override {

    {

      llvm::WithColor Header(OS, llvm::raw_ostream::Colors::RED, /*Bold=*/true);

      OS << "=== Beginning data flow analysis ===\n";

    }

    if (auto *D = CFG.getDecl()) {

      D->print(OS);

      OS << "\n";

      D->dump(OS);

    }

    CurrentCFG = &CFG.getCFG();

    CurrentCFG->print(OS, Analysis.getASTContext().getLangOpts(), ShowColors);

    CurrentAnalysis = &Analysis;

  }

  virtual void endAnalysis() override {

    llvm::WithColor Header(OS, llvm::raw_ostream::Colors::RED, /*Bold=*/true);

    unsigned Blocks = 0, Steps = 0;

    for (const auto &E : VisitCount) {

      ++Blocks;

      Steps += E.second;

    }

    llvm::errs() << "=== Finished analysis: " << Blocks << " blocks in "

                 << Steps << " total steps ===\n";

  }

  virtual void enterBlock(const CFGBlock &Block) override {

    unsigned Count = ++VisitCount[&Block];

    {

      llvm::WithColor Header(OS, llvm::raw_ostream::Colors::RED, /*Bold=*/true);

      OS << "=== Entering block B" << Block.getBlockID() << " (iteration "

         << Count << ") ===\n";

    }

    Block.print(OS, CurrentCFG, CurrentAnalysis->getASTContext().getLangOpts(),

                ShowColors);

    CurrentBlock = &Block;

    CurrentElement = nullptr;

    CurrentElementIndex = 0;

  }

  virtual void enterElement(const CFGElement &Element) override {

    ++CurrentElementIndex;

    CurrentElement = ∈

    {

      llvm::WithColor Subheader(OS, llvm::raw_ostream::Colors::CYAN,

                                /*Bold=*/true);

      OS << "Processing element B" << CurrentBlock->getBlockID() << "."

         << CurrentElementIndex << ": ";

      Element.dumpToStream(OS);

    }

  }

  void recordState(TypeErasedDataflowAnalysisState &State) override {

    {

      llvm::WithColor Subheader(OS, llvm::raw_ostream::Colors::CYAN,

                                /*Bold=*/true);

      OS << "Computed state for B" << CurrentBlock->getBlockID() << "."

         << CurrentElementIndex << ":\n";

    }

    // FIXME: currently the environment dump is verbose and unenlightening.

    // FIXME: dump the user-defined lattice, too.

    State.Env.dump(OS);

    OS << "\n";

  }

  void blockConverged() override {

    OS << "B" << CurrentBlock->getBlockID() << " has converged!\n";

  }

  virtual void logText(llvm::StringRef S) override { OS << S << "\n"; }

};

} // namespace

std::unique_ptr<Logger> Logger::textual(llvm::raw_ostream &OS) {

  return std::make_unique<TextualLogger>(OS);

}

} // namespace clang::dataflow