[clang][modules] Infer framework modules in explicit builds

This patch enables inferring framework modules in explicit builds in all contexts. Until now, inferring framework modules only worked with `-fimplicit-module-maps` due to this block of code:

```
// HeaderSearch::loadFrameworkModule
  case LMM_InvalidModuleMap:
    // Try to infer a module map from the framework directory.
    if (HSOpts->ImplicitModuleMaps)
      ModMap.inferFrameworkModule(Dir, IsSystem, /*Parent=*/nullptr);
    break;
```

Reviewed By: Bigcheese

Differential Revision: https://reviews.llvm.org/D113880

1 files changed, 9 insertions, 0 deletions

diff --git a/clang/lib/Frontend/FrontendAction.cpp b/clang/lib/Frontend/FrontendAction.cpp
index 089f40b..c5b9e80 100644
--- a/clang/lib/Frontend/FrontendAction.cpp
+++ b/clang/lib/Frontend/FrontendAction.cpp
@@ -465,6 +465,15 @@ static bool loadModuleMapForModuleBuild(CompilerInstance &CI, bool IsSystem,
   if (SrcMgr.getBufferOrFake(ModuleMapID).getBufferSize() == Offset)
     Offset = 0;
 
+  // Infer framework module if possible.
+  if (HS.getModuleMap().canInferFrameworkModule(ModuleMap->getDir())) {
+    SmallString<128> InferredFrameworkPath = ModuleMap->getDir()->getName();
+    llvm::sys::path::append(InferredFrameworkPath,
+                            CI.getLangOpts().ModuleName + ".framework");
+    if (auto Dir = CI.getFileManager().getDirectory(InferredFrameworkPath))
+      (void)HS.getModuleMap().inferFrameworkModule(*Dir, IsSystem, nullptr);
+  }
+
   return false;
 }