[llvm-branch-commits] [clang] 81aaf55 - [Driver] Fix use of classic Flang as preprocessor

[Bryan Chan via llvm-branch-commits]

Author: Bryan Chan
Date: 2020-06-24T10:23:23-04:00
New Revision: 81aaf55790cfee9af273fcb820403eaa224ebe7f

URL: https://github.com/llvm/llvm-project/commit/81aaf55790cfee9af273fcb820403eaa224ebe7f
DIFF: https://github.com/llvm/llvm-project/commit/81aaf55790cfee9af273fcb820403eaa224ebe7f.diff

LOG: [Driver] Fix use of classic Flang as preprocessor

Added: 
    

Modified: 
    clang/include/clang/Driver/Types.def
    clang/lib/Driver/Driver.cpp
    clang/lib/Driver/Types.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/Driver/Types.def b/clang/include/clang/Driver/Types.def
index 382175dabcce..ec4d2983fca4 100644
--- a/clang/include/clang/Driver/Types.def
+++ b/clang/include/clang/Driver/Types.def
@@ -72,10 +72,10 @@ TYPE("ada",                      Ada,          INVALID,         nullptr,  phases
 TYPE("assembler",                PP_Asm,       INVALID,         "s",      phases::Assemble, phases::Link)
 TYPE("assembler-with-cpp",       Asm,          PP_Asm,          "S",      phases::Preprocess, phases::Assemble, phases::Link)
 #ifdef USE_CLASSIC_FLANG
-TYPE("f77",                      PP_F_FixedForm, INVALID,       "f",      phases::Compile, phases::Backend, phases::Assemble, phases::Link)
-TYPE("f77-cpp-input",            F_FixedForm,  PP_F_FixedForm,  "F",      phases::Preprocess, phases::Compile, phases::Backend, phases::Assemble, phases::Link)
-TYPE("f95",                      PP_F_FreeForm, INVALID,        "f95",    phases::Compile, phases::Backend, phases::Assemble, phases::Link)
-TYPE("f95-cpp-input",            F_FreeForm,   PP_F_FreeForm,   "F95",    phases::Preprocess, phases::Compile, phases::Backend, phases::Assemble, phases::Link)
+TYPE("f77",                      PP_F_FixedForm, INVALID,       "f",      phases::FortranFrontend, phases::Backend, phases::Assemble, phases::Link)
+TYPE("f77-cpp-input",            F_FixedForm,  PP_F_FixedForm,  "F",      phases::FortranFrontend, phases::Backend, phases::Assemble, phases::Link)
+TYPE("f95",                      PP_F_FreeForm, INVALID,        "f95",    phases::FortranFrontend, phases::Backend, phases::Assemble, phases::Link)
+TYPE("f95-cpp-input",            F_FreeForm,   PP_F_FreeForm,   "F95",    phases::FortranFrontend, phases::Backend, phases::Assemble, phases::Link)
 #else
 TYPE("f95",                      PP_Fortran,   INVALID,         nullptr,  phases::Compile, phases::Backend, phases::Assemble, phases::Link)
 TYPE("f95-cpp-input",            Fortran,      PP_Fortran,      nullptr,  phases::Preprocess, phases::Compile, phases::Backend, phases::Assemble, phases::Link)

diff  --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 5b5053f3bb73..41ff7f50af43 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -3306,6 +3306,11 @@ void Driver::handleArguments(Compilation &C, DerivedArgList &Args,
       if (InputArg->isClaimed())
         continue;
 
+      // Fortran input is preprocessed using the frontend.
+      if (InitialPhase == phases::FortranFrontend &&
+          FinalPhase == phases::Preprocess)
+        continue;
+
       // Claim here to avoid the more general unused warning.
       InputArg->claim();
 

diff  --git a/clang/lib/Driver/Types.cpp b/clang/lib/Driver/Types.cpp
index 2f2d46cfde66..fb136a7f625e 100755
--- a/clang/lib/Driver/Types.cpp
+++ b/clang/lib/Driver/Types.cpp
@@ -46,9 +46,11 @@ const char *types::getTypeName(ID Id) {
 
 types::ID types::getPreprocessedType(ID Id) {
   ID PPT = getInfo(Id).PreprocessedType;
+#ifndef USE_CLASSIC_FLANG
   assert((llvm::is_contained(getInfo(Id).Phases, phases::Preprocess) !=
           (PPT == TY_INVALID)) &&
          "Unexpected Preprocess Type.");
+#endif
   return PPT;
 }
 
@@ -354,14 +356,24 @@ void types::getCompilationPhases(const clang::driver::Driver &Driver,
   types::getCompilationPhases(Id, PhaseList);
 
   // Filter to compiler mode. When the compiler is run as a preprocessor then
-  // compilation is not an option.
+  // compilation is not an option, except when the input is Fortran, for which
+  // preprocessing may be delegated to the classic Flang frontend.
   // -S runs the compiler in Assembly listing mode.
   if (Driver.CCCIsCPP() || DAL.getLastArg(options::OPT_E) ||
       DAL.getLastArg(options::OPT__SLASH_EP) ||
       DAL.getLastArg(options::OPT_M, options::OPT_MM) ||
       DAL.getLastArg(options::OPT__SLASH_P))
+#ifdef USE_CLASSIC_FLANG
+    llvm::copy_if(PhaseList, std::back_inserter(P),
+                  [&](phases::ID Phase) {
+                    return (Phase <= phases::Preprocess ||
+                            (Phase == phases::FortranFrontend &&
+                             Driver.IsFlangMode()));
+                  });
+#else
     llvm::copy_if(PhaseList, std::back_inserter(P),
                   [](phases::ID Phase) { return Phase <= phases::Preprocess; });
+#endif
 
   // --precompile only runs up to precompilation.
   // This is a clang extension and is not compatible with GCC.