[modules-ts] Fold together -x c++ and -x c++-module at -cc1 level.

The driver needs to know whether it's building a module interface or
implementation unit because it affects which outputs it produces and how it
builds the command pipeline. But the frontend doesn't need to know and should
not care: all it needs to know is what action it is being asked to perform on
the input.

(This is in preparation for permitting -emit-obj to be used on a module
interface unit to produce object code without going via a "full" PCM file.)

llvm-svn: 300611

3 files changed, 19 insertions, 5 deletions

diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 4259b629728..b6887b87584 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -649,8 +649,24 @@ static void addDashXForInput(const ArgList &Args, const InputInfo &Input,
   CmdArgs.push_back("-x");
   if (Args.hasArg(options::OPT_rewrite_objc))
     CmdArgs.push_back(types::getTypeName(types::TY_PP_ObjCXX));
-  else
-    CmdArgs.push_back(types::getTypeName(Input.getType()));
+  else {
+    // Map the driver type to the frontend type. This is mostly an identity
+    // mapping, except that the distinction between module interface units
+    // and other source files does not exist at the frontend layer.
+    const char *ClangType;
+    switch (Input.getType()) {
+    case types::TY_CXXModule:
+      ClangType = "c++";
+      break;
+    case types::TY_PP_CXXModule:
+      ClangType = "c++-cpp-output";
+      break;
+    default:
+      ClangType = types::getTypeName(Input.getType());
+      break;
+    }
+    CmdArgs.push_back(ClangType);
+  }
 }
 
 static void appendUserToPath(SmallVectorImpl<char> &Result) {
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index ab9f20304c9..05db4577ab9 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1353,13 +1353,11 @@ static InputKind ParseFrontendArgs(FrontendOptions &Opts, ArgList &Args,
       .Case("cl", IK_OpenCL)
       .Case("cuda", IK_CUDA)
       .Case("c++", IK_CXX)
-      .Case("c++-module", IK_CXX)
       .Case("objective-c", IK_ObjC)
       .Case("objective-c++", IK_ObjCXX)
       .Case("cpp-output", IK_PreprocessedC)
       .Case("assembler-with-cpp", IK_Asm)
       .Case("c++-cpp-output", IK_PreprocessedCXX)
-      .Case("c++-module-cpp-output", IK_PreprocessedCXX)
       .Case("cuda-cpp-output", IK_PreprocessedCuda)
       .Case("objective-c-cpp-output", IK_PreprocessedObjC)
       .Case("objc-cpp-output", IK_PreprocessedObjC)
diff --git a/clang/test/Driver/modules-ts.cpp b/clang/test/Driver/modules-ts.cpp
index 0fdc61b6f9c..fd3391479ee 100644
--- a/clang/test/Driver/modules-ts.cpp
+++ b/clang/test/Driver/modules-ts.cpp
@@ -4,7 +4,7 @@
 //
 // CHECK-PRECOMPILE: -cc1 {{.*}} -emit-module-interface
 // CHECK-PRECOMPILE-SAME: -o {{.*}}.pcm
-// CHECK-PRECOMPILE-SAME: -x c++-module
+// CHECK-PRECOMPILE-SAME: -x c++
 // CHECK-PRECOMPILE-SAME: modules-ts.cpp
 
 // Check compiling a .pcm file to a .o file.