Windows precompiled header support in GN

tools/gn/ninja_binary_target_writer.h

Index: tools/gn/ninja_binary_target_writer.h
diff --git a/tools/gn/ninja_binary_target_writer.h b/tools/gn/ninja_binary_target_writer.h
index 977e9823fe4fd075949b2f1d9058126cc66ac541..408f76d1584dd023ad17e77b8d7551421948010a 100644
--- a/tools/gn/ninja_binary_target_writer.h
+++ b/tools/gn/ninja_binary_target_writer.h
@@ -12,6 +12,7 @@
 #include "tools/gn/unique_vector.h"
 
 struct EscapeOptions;
+class SourceFileTypeSet;
 
 // Writes a .ninja file for a binary target type (an executable, a shared
 // library, or a static library).
@@ -24,10 +25,43 @@ class NinjaBinaryTargetWriter : public NinjaTargetWriter {
 
  private:
   typedef std::set<OutputFile> OutputFileSet;
-
-  void WriteCompilerVars();
-  void WriteSources(std::vector<OutputFile>* object_files,
+  class SourceFileTypeSet;
+
+  // Writes all flags for the compiler: includes, defines, cflags, etc.
+  // Any .pch files this function generates references to will be appended to
+  // the *pch_files vector.
+  void WriteCompilerVars(const SourceFileTypeSet& used_types);
+  void WriteOneFlag(
+      SubstitutionType subst_enum,
+      const std::vector<std::string>& (ConfigValues::* getter)() const,
+      EscapeOptions flag_escape_options);
+
+  void WritePrecompiledHeaderCommands(const SourceFileTypeSet& used_types,
+                                      const OutputFile& input_dep,
+                                      std::vector<OutputFile>* object_files);
+  void WritePrecompiledHeaderCommand(SubstitutionType flag_type,
+                                     Toolchain::ToolType tool_type,
+                                     const OutputFile& input_dep,
+                                     std::vector<OutputFile>* object_files);
+
+  // extra_deps are additional dependencies to run before the rule.
+  //
+  // iorder_only_dep is the name of the stamp file that covers the dependencies
+  // that must be run before doing any compiles.
+  //
+  // The files produced by the compiler will be added to two output vectors.
+  void WriteSources(const std::vector<OutputFile>& extra_deps,
+                    const OutputFile& order_only_dep,
+                    std::vector<OutputFile>* object_files,
                     std::vector<SourceFile>* other_files);
+
+  // Writes a build line.
+  void WriteCompilerBuildLine(const SourceFile& source,
+                              const std::vector<OutputFile>& extra_deps,
+                              const OutputFile& order_only_dep,
+                              Toolchain::ToolType tool_type,
+                              const std::vector<OutputFile>& outputs);
+
   void WriteLinkerStuff(const std::vector<OutputFile>& object_files,
                         const std::vector<SourceFile>& other_files);
   void WriteLinkerFlags(const SourceFile* optional_def_file);
@@ -78,8 +112,28 @@ class NinjaBinaryTargetWriter : public NinjaTargetWriter {
                                Toolchain::ToolType* computed_tool_type,
                                std::vector<OutputFile>* outputs) const;
 
+  // Appends the object files generated by the given source set to the given
+  // output vector.
+  void AddSourceSetObjectFiles(const Target* source_set,
+                               UniqueVector<OutputFile>* obj_files) const;
+
+  // Returns the object files for the precompiled header of the given type
+  // (flag type and tool type must match). The given target is used rather than
+  // this class' target_ so any target's object files can be retrieved.
+  void GetWindowsPCHObjectFiles(const Target* target,
+                                SubstitutionType flag_type,
+                                Toolchain::ToolType tool_type,
+                                std::vector<OutputFile>* outputs) const;
+
+  // Returns the computed name of the Windows .pch file for the given
+  // flag type (C/C++/ObjC/ObjC++).
+  OutputFile GetWindowsPCHFile(SubstitutionType flag_type) const;
+
   const Tool* tool_;
 
+  // Cached version of the prefix used for rule types for this toolchain.
+  std::string rule_prefix_;
+
   DISALLOW_COPY_AND_ASSIGN(NinjaBinaryTargetWriter);
 };