//===-- CompileUnit.cpp -----------------------------------------*- 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 "lldb/Symbol/CompileUnit.h"
#include "lldb/Core/Module.h"
#include "lldb/Symbol/LineTable.h"
#include "lldb/Symbol/SymbolFile.h"
#include "lldb/Symbol/VariableList.h"
#include "lldb/Target/Language.h"
#include "lldb/Utility/Timer.h"

using namespace lldb;
using namespace lldb_private;

CompileUnit::CompileUnit(const lldb::ModuleSP &module_sp, void *user_data,
                         const char *pathname, const lldb::user_id_t cu_sym_id,
                         lldb::LanguageType language,
                         lldb_private::LazyBool is_optimized)
    : CompileUnit(module_sp, user_data, FileSpec(pathname), cu_sym_id, language,
                  is_optimized) {}

CompileUnit::CompileUnit(const lldb::ModuleSP &module_sp, void *user_data,
                         const FileSpec &fspec, const lldb::user_id_t cu_sym_id,
                         lldb::LanguageType language,
                         lldb_private::LazyBool is_optimized)
    : ModuleChild(module_sp), UserID(cu_sym_id), m_user_data(user_data),
      m_language(language), m_flags(0), m_file_spec(fspec),
      m_is_optimized(is_optimized) {
  if (language != eLanguageTypeUnknown)
    m_flags.Set(flagsParsedLanguage);
  assert(module_sp);
}

void CompileUnit::CalculateSymbolContext(SymbolContext *sc) {
  sc->comp_unit = this;
  GetModule()->CalculateSymbolContext(sc);
}

ModuleSP CompileUnit::CalculateSymbolContextModule() { return GetModule(); }

CompileUnit *CompileUnit::CalculateSymbolContextCompileUnit() { return this; }

void CompileUnit::DumpSymbolContext(Stream *s) {
  GetModule()->DumpSymbolContext(s);
  s->Printf(", CompileUnit{0x%8.8" PRIx64 "}", GetID());
}

void CompileUnit::GetDescription(Stream *s,
                                 lldb::DescriptionLevel level) const {
  const char *language = Language::GetNameForLanguageType(m_language);
  *s << "id = " << (const UserID &)*this << ", file = \""
     << this->GetPrimaryFile() << "\", language = \"" << language << '"';
}

void CompileUnit::ForeachFunction(
    llvm::function_ref<bool(const FunctionSP &)> lambda) const {
  std::vector<lldb::FunctionSP> sorted_functions;
  sorted_functions.reserve(m_functions_by_uid.size());
  for (auto &p : m_functions_by_uid)
    sorted_functions.push_back(p.second);
  llvm::sort(sorted_functions.begin(), sorted_functions.end(),
             [](const lldb::FunctionSP &a, const lldb::FunctionSP &b) {
               return a->GetID() < b->GetID();
             });

  for (auto &f : sorted_functions)
    if (lambda(f))
      return;
}

lldb::FunctionSP CompileUnit::FindFunction(
    llvm::function_ref<bool(const FunctionSP &)> matching_lambda) {
  static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
  Timer scoped_timer(func_cat, "CompileUnit::FindFunction");

  lldb::ModuleSP module = CalculateSymbolContextModule();

  if (!module)
    return {};

  SymbolFile *symbol_file = module->GetSymbolFile();

  if (!symbol_file)
    return {};

  // m_functions_by_uid is filled in lazily but we need all the entries.
  symbol_file->ParseFunctions(*this);

  for (auto &p : m_functions_by_uid) {
    if (matching_lambda(p.second))
      return p.second;
  }
  return {};
}

// Dump the current contents of this object. No functions that cause on demand
// parsing of functions, globals, statics are called, so this is a good
// function to call to get an idea of the current contents of the CompileUnit
// object.
void CompileUnit::Dump(Stream *s, bool show_context) const {
  const char *language = Language::GetNameForLanguageType(m_language);

  s->Printf("%p: ", static_cast<const void *>(this));
  s->Indent();
  *s << "CompileUnit" << static_cast<const UserID &>(*this) << ", language = \""
     << language << "\", file = '" << GetPrimaryFile() << "'\n";

  //  m_types.Dump(s);

  if (m_variables.get()) {
    s->IndentMore();
    m_variables->Dump(s, show_context);
    s->IndentLess();
  }

  if (!m_functions_by_uid.empty()) {
    s->IndentMore();
    ForeachFunction([&s, show_context](const FunctionSP &f) {
      f->Dump(s, show_context);
      return false;
    });

    s->IndentLess();
    s->EOL();
  }
}

// Add a function to this compile unit
void CompileUnit::AddFunction(FunctionSP &funcSP) {
  m_functions_by_uid[funcSP->GetID()] = funcSP;
}

FunctionSP CompileUnit::FindFunctionByUID(lldb::user_id_t func_uid) {
  auto it = m_functions_by_uid.find(func_uid);
  if (it == m_functions_by_uid.end())
    return FunctionSP();
  return it->second;
}

lldb::LanguageType CompileUnit::GetLanguage() {
  if (m_language == eLanguageTypeUnknown) {
    if (m_flags.IsClear(flagsParsedLanguage)) {
      m_flags.Set(flagsParsedLanguage);
      if (SymbolFile *symfile = GetModule()->GetSymbolFile())
        m_language = symfile->ParseLanguage(*this);
    }
  }
  return m_language;
}

LineTable *CompileUnit::GetLineTable() {
  if (m_line_table_up == nullptr) {
    if (m_flags.IsClear(flagsParsedLineTable)) {
      m_flags.Set(flagsParsedLineTable);
      if (SymbolFile *symfile = GetModule()->GetSymbolFile())
        symfile->ParseLineTable(*this);
    }
  }
  return m_line_table_up.get();
}

void CompileUnit::SetLineTable(LineTable *line_table) {
  if (line_table == nullptr)
    m_flags.Clear(flagsParsedLineTable);
  else
    m_flags.Set(flagsParsedLineTable);
  m_line_table_up.reset(line_table);
}

void CompileUnit::SetSupportFiles(const FileSpecList &support_files) {
  m_support_files = support_files;
}

DebugMacros *CompileUnit::GetDebugMacros() {
  if (m_debug_macros_sp.get() == nullptr) {
    if (m_flags.IsClear(flagsParsedDebugMacros)) {
      m_flags.Set(flagsParsedDebugMacros);
      if (SymbolFile *symfile = GetModule()->GetSymbolFile())
        symfile->ParseDebugMacros(*this);
    }
  }

  return m_debug_macros_sp.get();
}

void CompileUnit::SetDebugMacros(const DebugMacrosSP &debug_macros_sp) {
  if (debug_macros_sp.get() == nullptr)
    m_flags.Clear(flagsParsedDebugMacros);
  else
    m_flags.Set(flagsParsedDebugMacros);
  m_debug_macros_sp = debug_macros_sp;
}

VariableListSP CompileUnit::GetVariableList(bool can_create) {
  if (m_variables.get() == nullptr && can_create) {
    SymbolContext sc;
    CalculateSymbolContext(&sc);
    assert(sc.module_sp);
    sc.module_sp->GetSymbolFile()->ParseVariablesForContext(sc);
  }

  return m_variables;
}

uint32_t CompileUnit::FindLineEntry(uint32_t start_idx, uint32_t line,
                                    const FileSpec *file_spec_ptr, bool exact,
                                    LineEntry *line_entry_ptr) {
  uint32_t file_idx = 0;

  if (file_spec_ptr) {
    file_idx = GetSupportFiles().FindFileIndex(1, *file_spec_ptr, true);
    if (file_idx == UINT32_MAX)
      return UINT32_MAX;
  } else {
    // All the line table entries actually point to the version of the Compile
    // Unit that is in the support files (the one at 0 was artificially added.)
    // So prefer the one further on in the support files if it exists...
    const FileSpecList &support_files = GetSupportFiles();
    const bool full = true;
    file_idx = support_files.FindFileIndex(
        1, support_files.GetFileSpecAtIndex(0), full);
    if (file_idx == UINT32_MAX)
      file_idx = 0;
  }
  LineTable *line_table = GetLineTable();
  if (line_table)
    return line_table->FindLineEntryIndexByFileIndex(start_idx, file_idx, line,
                                                     exact, line_entry_ptr);
  return UINT32_MAX;
}

void CompileUnit::ResolveSymbolContext(const FileSpec &file_spec,
                                       uint32_t line, bool check_inlines,
                                       bool exact,
                                       SymbolContextItem resolve_scope,
                                       SymbolContextList &sc_list) {
  // First find all of the file indexes that match our "file_spec". If
  // "file_spec" has an empty directory, then only compare the basenames when
  // finding file indexes
  std::vector<uint32_t> file_indexes;
  const bool full_match = (bool)file_spec.GetDirectory();
  bool file_spec_matches_cu_file_spec =
      FileSpec::Equal(file_spec, this->GetPrimaryFile(), full_match);

  // If we are not looking for inlined functions and our file spec doesn't
  // match then we are done...
  if (!file_spec_matches_cu_file_spec && !check_inlines)
    return;

  uint32_t file_idx =
      GetSupportFiles().FindFileIndex(1, file_spec, true);
  while (file_idx != UINT32_MAX) {
    file_indexes.push_back(file_idx);
    file_idx = GetSupportFiles().FindFileIndex(file_idx + 1, file_spec, true);
  }

  const size_t num_file_indexes = file_indexes.size();
  if (num_file_indexes == 0)
    return;

  SymbolContext sc(GetModule());
  sc.comp_unit = this;

  if (line == 0) {
    if (file_spec_matches_cu_file_spec && !check_inlines) {
      // only append the context if we aren't looking for inline call sites by
      // file and line and if the file spec matches that of the compile unit
      sc_list.Append(sc);
    }
    return;
  }

  LineTable *line_table = sc.comp_unit->GetLineTable();

  if (line_table == nullptr)
    return;

  uint32_t line_idx;
  LineEntry line_entry;

  if (num_file_indexes == 1) {
    // We only have a single support file that matches, so use the line
    // table function that searches for a line entries that match a single
    // support file index
    line_idx = line_table->FindLineEntryIndexByFileIndex(
        0, file_indexes.front(), line, exact, &line_entry);
  } else {
    // We found multiple support files that match "file_spec" so use the
    // line table function that searches for a line entries that match a
    // multiple support file indexes.
    line_idx = line_table->FindLineEntryIndexByFileIndex(0, file_indexes, line,
                                                         exact, &line_entry);
  }
  
  // If "exact == true", then "found_line" will be the same as "line". If
  // "exact == false", the "found_line" will be the closest line entry
  // with a line number greater than "line" and we will use this for our
  // subsequent line exact matches below.
  uint32_t found_line = line_entry.line;
  
  while (line_idx != UINT32_MAX) {
    // If they only asked for the line entry, then we're done, we can
    // just copy that over. But if they wanted more than just the line
    // number, fill it in.
    if (resolve_scope == eSymbolContextLineEntry) {
      sc.line_entry = line_entry;
    } else {
      line_entry.range.GetBaseAddress().CalculateSymbolContext(&sc,
                                                               resolve_scope);
    }

    sc_list.Append(sc);
    if (num_file_indexes == 1)
      line_idx = line_table->FindLineEntryIndexByFileIndex(
          line_idx + 1, file_indexes.front(), found_line, true, &line_entry);
    else
      line_idx = line_table->FindLineEntryIndexByFileIndex(
          line_idx + 1, file_indexes, found_line, true, &line_entry);
  }
}

bool CompileUnit::GetIsOptimized() {
  if (m_is_optimized == eLazyBoolCalculate) {
    m_is_optimized = eLazyBoolNo;
    if (SymbolFile *symfile = GetModule()->GetSymbolFile()) {
      if (symfile->ParseIsOptimized(*this))
        m_is_optimized = eLazyBoolYes;
    }
  }
  return m_is_optimized;
}

void CompileUnit::SetVariableList(VariableListSP &variables) {
  m_variables = variables;
}

const std::vector<SourceModule> &CompileUnit::GetImportedModules() {
  if (m_imported_modules.empty() &&
      m_flags.IsClear(flagsParsedImportedModules)) {
    m_flags.Set(flagsParsedImportedModules);
    if (SymbolFile *symfile = GetModule()->GetSymbolFile()) {
      SymbolContext sc;
      CalculateSymbolContext(&sc);
      symfile->ParseImportedModules(sc, m_imported_modules);
    }
  }
  return m_imported_modules;
}

bool CompileUnit::ForEachExternalModule(
    llvm::DenseSet<SymbolFile *> &visited_symbol_files,
    llvm::function_ref<bool(Module &)> lambda) {
  if (SymbolFile *symfile = GetModule()->GetSymbolFile())
    return symfile->ForEachExternalModule(*this, visited_symbol_files, lambda);
  return false;
}

const FileSpecList &CompileUnit::GetSupportFiles() {
  if (m_support_files.GetSize() == 0) {
    if (m_flags.IsClear(flagsParsedSupportFiles)) {
      m_flags.Set(flagsParsedSupportFiles);
      if (SymbolFile *symfile = GetModule()->GetSymbolFile())
        symfile->ParseSupportFiles(*this, m_support_files);
    }
  }
  return m_support_files;
}

void *CompileUnit::GetUserData() const { return m_user_data; }
