[clang] 853ca54 - [C++20][Modules][6/8] Record direct module imports.

[Iain Sandoe via cfe-commits]

Author: Iain Sandoe
Date: 2022-02-27T10:07:11Z
New Revision: 853ca5472314e109b98e46f0985f27f79e17d2bd

URL: https://github.com/llvm/llvm-project/commit/853ca5472314e109b98e46f0985f27f79e17d2bd
DIFF: https://github.com/llvm/llvm-project/commit/853ca5472314e109b98e46f0985f27f79e17d2bd.diff

LOG: [C++20][Modules][6/8] Record direct module imports.

This is a small cache to avoid having to check both Exports and
Imports.

Differential Revision: https://reviews.llvm.org/D118589

Added: 
    

Modified: 
    clang/include/clang/Sema/Sema.h
    clang/lib/Sema/SemaModule.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 0b872c48482db..9937846e05658 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -2219,6 +2219,9 @@ class Sema final {
   /// The global module fragment of the current translation unit.
   clang::Module *GlobalModuleFragment = nullptr;
 
+  /// The modules we imported directly.
+  llvm::SmallPtrSet<clang::Module *, 8> DirectModuleImports;
+
   /// Namespace definitions that we will export when they finish.
   llvm::SmallPtrSet<const NamespaceDecl*, 8> DeferredExportedNamespaces;
 
@@ -2246,6 +2249,10 @@ class Sema final {
     return Entity->getOwningModule();
   }
 
+  bool isModuleDirectlyImported(const Module *M) {
+    return DirectModuleImports.contains(M);
+  }
+
   /// Make a merged definition of an existing hidden definition \p ND
   /// visible at the specified location.
   void makeMergedDefinitionVisible(NamedDecl *ND);

diff  --git a/clang/lib/Sema/SemaModule.cpp b/clang/lib/Sema/SemaModule.cpp
index 0606b3a4edae8..a829693fafebc 100644
--- a/clang/lib/Sema/SemaModule.cpp
+++ b/clang/lib/Sema/SemaModule.cpp
@@ -514,6 +514,11 @@ DeclResult Sema::ActOnModuleImport(SourceLocation StartLoc,
     assert(ThisModule && "was expecting a module if building one");
   }
 
+  // In some cases we need to know if an entity was present in a directly-
+  // imported module (as opposed to a transitive import).  This avoids
+  // searching both Imports and Exports.
+  DirectModuleImports.insert(Mod);
+
   return Import;
 }