-frewrite-imports: Add support for wildcard rules in umbrella modules with

This trips over a few other limitations, but in the interests of incremental development I'm starting here & I'll look at the issues with -verify and filesystem checks (the fact that the behavior depends on the existence of a 'foo' directory even though it shouldn't need it), etc.

Reviewers: rsmith

Differential Revision: https://reviews.llvm.org/D61656

llvm-svn: 360195

2 files changed, 18 insertions, 4 deletions

diff --git a/clang/lib/Basic/Module.cpp b/clang/lib/Basic/Module.cpp
index b405ab621d3..f394f26e550 100644
--- a/clang/lib/Basic/Module.cpp
+++ b/clang/lib/Basic/Module.cpp
@@ -321,6 +321,21 @@ Module *Module::findSubmodule(StringRef Name) const {
   return SubModules[Pos->getValue()];
 }
 
+Module *Module::findOrInferSubmodule(StringRef Name) {
+  llvm::StringMap<unsigned>::const_iterator Pos = SubModuleIndex.find(Name);
+  if (Pos != SubModuleIndex.end())
+    return SubModules[Pos->getValue()];
+  if (!InferSubmodules)
+    return nullptr;
+  Module *Result = new Module(Name, SourceLocation(), this, false, InferExplicitSubmodules, 0);
+  Result->InferExplicitSubmodules = InferExplicitSubmodules;
+  Result->InferSubmodules = InferSubmodules;
+  Result->InferExportWildcard = InferExportWildcard;
+  if (Result->InferExportWildcard)
+    Result->Exports.push_back(Module::ExportDecl(nullptr, true));
+  return Result;
+}
+
 void Module::getExportedModules(SmallVectorImpl<Module *> &Exported) const {
   // All non-explicit submodules are exported.
   for (std::vector<Module *>::const_iterator I = SubModules.begin(),
diff --git a/clang/lib/Lex/Pragma.cpp b/clang/lib/Lex/Pragma.cpp
index ba1b73e7f4b..8aff163d798 100644
--- a/clang/lib/Lex/Pragma.cpp
+++ b/clang/lib/Lex/Pragma.cpp
@@ -1584,16 +1584,15 @@ struct PragmaModuleBeginHandler : public PragmaHandler {
 
     // Find the module we're entering. We require that a module map for it
     // be loaded or implicitly loadable.
-    // FIXME: We could create the submodule here. We'd need to know whether
-    // it's supposed to be explicit, but not much else.
-    Module *M = PP.getHeaderSearchInfo().lookupModule(Current);
+    auto &HSI = PP.getHeaderSearchInfo();
+    Module *M = HSI.lookupModule(Current);
     if (!M) {
       PP.Diag(ModuleName.front().second,
               diag::err_pp_module_begin_no_module_map) << Current;
       return;
     }
     for (unsigned I = 1; I != ModuleName.size(); ++I) {
-      auto *NewM = M->findSubmodule(ModuleName[I].first->getName());
+      auto *NewM = M->findOrInferSubmodule(ModuleName[I].first->getName());
       if (!NewM) {
         PP.Diag(ModuleName[I].second, diag::err_pp_module_begin_no_submodule)
           << M->getFullModuleName() << ModuleName[I].first;