[modules] Add -cc1 flag -fmodules-embed-all-files.

This flag causes all files that were read by the compilation to be embedded
into a produced module file. This is useful for distributed build systems that
use an include scanning system to determine which files are "needed" by a
compilation, and only provide those files to remote compilation workers. Since
using a module can require any file that is part of that module (or anything it
transitively includes), files that are not found by an include scanner can be
required in a regular build using explicit modules. With this flag, only files
that are actually referenced by transitively-#included files are required to be
present on the build machine.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@253950 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 17 insertions, 1 deletions

diff --git a/include/clang/Basic/SourceManager.h b/include/clang/Basic/SourceManager.h
index ae5f2bde37..5006b00929 100644
--- a/include/clang/Basic/SourceManager.h
+++ b/include/clang/Basic/SourceManager.h
@@ -566,6 +566,11 @@ class SourceManager : public RefCountedBase<SourceManager> {
   /// (likely to change while trying to use them). Defaults to false.
   bool UserFilesAreVolatile;
 
+  /// \brief True if all files read during this compilation should be treated
+  /// as transient (may not be present in later compilations using a module
+  /// file created from this compilation). Defaults to false.
+  bool FilesAreTransient;
+
   struct OverriddenFilesInfoTy {
     /// \brief Files that have been overridden with the contents from another
     /// file.
@@ -864,6 +869,12 @@ public:
   /// the module is used).
   void embedFileContentsInModule(const FileEntry *SourceFile);
 
+  /// \brief Request that all files that are read during this compilation be
+  /// written to any created module file.
+  void setEmbedAllFileContentsInModule(bool Embed) {
+    FilesAreTransient = Embed;
+  }
+
   //===--------------------------------------------------------------------===//
   // FileID manipulation methods.
   //===--------------------------------------------------------------------===//
diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index 56caea85b1..d510e19ea9 100644
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -381,6 +381,9 @@ def fmodules_embed_file_EQ : Joined<["-"], "fmodules-embed-file=">,
   MetaVarName<"<file>">,
   HelpText<"Embed the contents of the specified file into the module file "
            "being compiled.">;
+def fmodules_embed_all_files : Joined<["-"], "fmodules-embed-all-files">,
+  HelpText<"Embed the contents of all files read by this compilation into "
+           "the produced module file.">;
 def fmodules_local_submodule_visibility :
   Flag<["-"], "fmodules-local-submodule-visibility">,
   HelpText<"Enforce name visibility rules across submodules of the same "
diff --git a/include/clang/Frontend/FrontendOptions.h b/include/clang/Frontend/FrontendOptions.h
index 186e8cf3e7..c800a5148e 100644
--- a/include/clang/Frontend/FrontendOptions.h
+++ b/include/clang/Frontend/FrontendOptions.h
@@ -150,6 +150,8 @@ public:
                                            ///< dumps in AST dumps.
   unsigned BuildingImplicitModule : 1;     ///< Whether we are performing an
                                            ///< implicit module build.
+  unsigned ModulesEmbedAllFiles : 1;       ///< Whether we should embed all used
+                                           ///< files into the PCM file.
 
   CodeCompleteOptions CodeCompleteOpts;
 
@@ -272,7 +274,7 @@ public:
     FixToTemporaries(false), ARCMTMigrateEmitARCErrors(false),
     SkipFunctionBodies(false), UseGlobalModuleIndex(true),
     GenerateGlobalModuleIndex(true), ASTDumpDecls(false), ASTDumpLookups(false),
-    BuildingImplicitModule(false),
+    BuildingImplicitModule(false), ModulesEmbedAllFiles(false),
     ARCMTAction(ARCMT_None), ObjCMTAction(ObjCMT_None),
     ProgramAction(frontend::ParseSyntaxOnly)
   {}