/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "compiler_options.h"

#include <fstream>

#include "android-base/stringprintf.h"

#include "arch/instruction_set.h"
#include "arch/instruction_set_features.h"
#include "base/runtime_debug.h"
#include "base/variant_map.h"
#include "class_linker.h"
#include "cmdline_parser.h"
#include "compiler_options_map-inl.h"
#include "dex/dex_file-inl.h"
#include "dex/verification_results.h"
#include "dex/verified_method.h"
#include "runtime.h"
#include "scoped_thread_state_change-inl.h"
#include "simple_compiler_options_map.h"

namespace art {

CompilerOptions::CompilerOptions()
    : compiler_filter_(CompilerFilter::kDefaultCompilerFilter),
      huge_method_threshold_(kDefaultHugeMethodThreshold),
      large_method_threshold_(kDefaultLargeMethodThreshold),
      small_method_threshold_(kDefaultSmallMethodThreshold),
      tiny_method_threshold_(kDefaultTinyMethodThreshold),
      num_dex_methods_threshold_(kDefaultNumDexMethodsThreshold),
      inline_max_code_units_(kUnsetInlineMaxCodeUnits),
      instruction_set_(kRuntimeISA == InstructionSet::kArm ? InstructionSet::kThumb2 : kRuntimeISA),
      instruction_set_features_(nullptr),
      no_inline_from_(),
      dex_files_for_oat_file_(),
      image_classes_(),
      verification_results_(nullptr),
      image_type_(ImageType::kNone),
      compiling_with_core_image_(false),
      baseline_(false),
      debuggable_(false),
      generate_debug_info_(kDefaultGenerateDebugInfo),
      generate_mini_debug_info_(kDefaultGenerateMiniDebugInfo),
      generate_build_id_(false),
      implicit_null_checks_(true),
      implicit_so_checks_(true),
      implicit_suspend_checks_(false),
      compile_pic_(false),
      dump_timings_(false),
      dump_pass_timings_(false),
      dump_stats_(false),
      top_k_profile_threshold_(kDefaultTopKProfileThreshold),
      profile_compilation_info_(nullptr),
      verbose_methods_(),
      abort_on_hard_verifier_failure_(false),
      abort_on_soft_verifier_failure_(false),
      init_failure_output_(nullptr),
      dump_cfg_file_name_(""),
      dump_cfg_append_(false),
      force_determinism_(false),
      deduplicate_code_(true),
      count_hotness_in_compiled_code_(false),
      resolve_startup_const_strings_(false),
      check_profiled_methods_(ProfileMethodsCheck::kNone),
      max_image_block_size_(std::numeric_limits<uint32_t>::max()),
      register_allocation_strategy_(RegisterAllocator::kRegisterAllocatorDefault),
      passes_to_run_(nullptr) {
}

CompilerOptions::~CompilerOptions() {
  // Everything done by member destructors.
  // The definitions of classes forward-declared in the header have now been #included.
}

namespace {

bool kEmitRuntimeReadBarrierChecks = kIsDebugBuild &&
    RegisterRuntimeDebugFlag(&kEmitRuntimeReadBarrierChecks);

}  // namespace

bool CompilerOptions::EmitRunTimeChecksInDebugMode() const {
  // Run-time checks (e.g. Marking Register checks) are only emitted in slow-debug mode.
  return kEmitRuntimeReadBarrierChecks;
}

bool CompilerOptions::ParseDumpInitFailures(const std::string& option, std::string* error_msg) {
  init_failure_output_.reset(new std::ofstream(option));
  if (init_failure_output_.get() == nullptr) {
    *error_msg = "Failed to construct std::ofstream";
    return false;
  } else if (init_failure_output_->fail()) {
    *error_msg = android::base::StringPrintf(
        "Failed to open %s for writing the initialization failures.", option.c_str());
    init_failure_output_.reset();
    return false;
  }
  return true;
}

bool CompilerOptions::ParseRegisterAllocationStrategy(const std::string& option,
                                                      std::string* error_msg) {
  if (option == "linear-scan") {
    register_allocation_strategy_ = RegisterAllocator::Strategy::kRegisterAllocatorLinearScan;
  } else if (option == "graph-color") {
    register_allocation_strategy_ = RegisterAllocator::Strategy::kRegisterAllocatorGraphColor;
  } else {
    *error_msg = "Unrecognized register allocation strategy. Try linear-scan, or graph-color.";
    return false;
  }
  return true;
}

bool CompilerOptions::ParseCompilerOptions(const std::vector<std::string>& options,
                                           bool ignore_unrecognized,
                                           std::string* error_msg) {
  auto parser = CreateSimpleParser(ignore_unrecognized);
  CmdlineResult parse_result = parser.Parse(options);
  if (!parse_result.IsSuccess()) {
    *error_msg = parse_result.GetMessage();
    return false;
  }

  SimpleParseArgumentMap args = parser.ReleaseArgumentsMap();
  return ReadCompilerOptions(args, this, error_msg);
}

bool CompilerOptions::IsImageClass(const char* descriptor) const {
  // Historical note: We used to hold the set indirectly and there was a distinction between an
  // empty set and a null, null meaning to include all classes. However, the distiction has been
  // removed; if we don't have a profile, we treat it as an empty set of classes. b/77340429
  return image_classes_.find(StringPiece(descriptor)) != image_classes_.end();
}

const VerificationResults* CompilerOptions::GetVerificationResults() const {
  DCHECK(Runtime::Current()->IsAotCompiler());
  return verification_results_;
}

const VerifiedMethod* CompilerOptions::GetVerifiedMethod(const DexFile* dex_file,
                                                         uint32_t method_idx) const {
  MethodReference ref(dex_file, method_idx);
  return verification_results_->GetVerifiedMethod(ref);
}

bool CompilerOptions::IsMethodVerifiedWithoutFailures(uint32_t method_idx,
                                                      uint16_t class_def_idx,
                                                      const DexFile& dex_file) const {
  const VerifiedMethod* verified_method = GetVerifiedMethod(&dex_file, method_idx);
  if (verified_method != nullptr) {
    return !verified_method->HasVerificationFailures();
  }

  // If we can't find verification metadata, check if this is a system class (we trust that system
  // classes have their methods verified). If it's not, be conservative and assume the method
  // has not been verified successfully.

  // TODO: When compiling the boot image it should be safe to assume that everything is verified,
  // even if methods are not found in the verification cache.
  const char* descriptor = dex_file.GetClassDescriptor(dex_file.GetClassDef(class_def_idx));
  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
  Thread* self = Thread::Current();
  ScopedObjectAccess soa(self);
  bool is_system_class = class_linker->FindSystemClass(self, descriptor) != nullptr;
  if (!is_system_class) {
    self->ClearException();
  }
  return is_system_class;
}

}  // namespace art