Temporarily revert r137925 to appease buildbots. Original commit message:

Teach ModuleManager::addModule() to check whether a particular module
has already been loaded before allocating a new Module structure. If
the module has already been loaded (uniquing based on file name), then
just return the existing module rather than trying to load it again.

This allows us to load a DAG of modules. Introduce a simple test case
that forms a diamond-shaped module graph, and illustrates that a
source file importing the bottom of the diamond can see declarations
in all four of the modules that make up the diamond.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@137971 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Serialization/ASTReader.h b/include/clang/Serialization/ASTReader.h
index f00e805863acf5bf4ab9ac2bba4574dfa72a8ce5..514d36db919c45462d1b660d7fd3c42361afd669 100644 (file)
--- a/include/clang/Serialization/ASTReader.h
+++ b/include/clang/Serialization/ASTReader.h
@@ -507,11 +507,8 @@ public:
   ///
   /// \param ImportedBy The module that is importing this module, or NULL if
   /// this module is imported directly by the user.
-  ///
-  /// \return A pointer to the module that corresponds to this file name,
-  /// and a boolean indicating whether the module was newly added.
-  std::pair<Module *, bool> 
-  addModule(StringRef FileName, ModuleKind Type, Module *ImportedBy);
+  Module &addModule(StringRef FileName, ModuleKind Type,
+                    Module *ImportedBy);
   
   /// \brief Add an in-memory buffer the list of known buffers
   void addInMemoryBuffer(StringRef FileName, llvm::MemoryBuffer *Buffer);

diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index b635b38c10ac5c35bdef2051ec6d2d5a29c995d5..d81e9d8a36a47a4198a8be78bc546f26bb97c981 100644 (file)
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -2831,23 +2831,7 @@ ASTReader::ASTReadResult ASTReader::ReadAST(const std::string &FileName,
 ASTReader::ASTReadResult ASTReader::ReadASTCore(StringRef FileName,
                                                 ModuleKind Type,
                                                 Module *ImportedBy) {
-  Module *M;
-  bool NewModule;
-  llvm::tie(M, NewModule) = ModuleMgr.addModule(FileName, Type, ImportedBy);
-
-  if (!M) {
-    // We couldn't load the module.
-    std::string Msg = "Unable to load module \"" + FileName.str() + "\"";
-    Error(Msg);
-    return Failure;
-  }
-
-  if (!NewModule) {
-    // We've already loaded this module.
-    return Success;
-  }
-
-  Module &F = *M;
+  Module &F = ModuleMgr.addModule(FileName, Type, ImportedBy);
 
   if (FileName != "-") {
     CurrentDir = llvm::sys::path::parent_path(FileName);
@@ -5725,34 +5709,25 @@ llvm::MemoryBuffer *ModuleManager::lookupBuffer(StringRef Name) {
   return InMemoryBuffers[Entry];
 }
 
-std::pair<Module *, bool>
-ModuleManager::addModule(StringRef FileName, ModuleKind Type, 
-                         Module *ImportedBy) {
+/// \brief Creates a new module and adds it to the list of known modules
+Module &ModuleManager::addModule(StringRef FileName, ModuleKind Type,
+                                 Module *ImportedBy) {
+  Module *Current = new Module(Type);
+  Current->FileName = FileName.str();
+  Chain.push_back(Current);
+
   const FileEntry *Entry = FileMgr.getFile(FileName);
-  if (!Entry)
-    return std::make_pair(static_cast<Module*>(0), false);
-
-  // Check whether we already loaded this module, before 
-  Module *&ModuleEntry = Modules[Entry];
-  bool NewModule = false;
-  if (!ModuleEntry) {
-    // Allocate a new module.
-    Module *New = new Module(Type);
-    New->FileName = FileName.str();
-    Chain.push_back(New);
-  
-    NewModule = true;
-    ModuleEntry = New;
-  }
+  // FIXME: Check whether we already loaded this module, before 
+  Modules[Entry] = Current;
 
   if (ImportedBy) {
-    ModuleEntry->ImportedBy.insert(ImportedBy);
-    ImportedBy->Imports.insert(ModuleEntry);
+    Current->ImportedBy.insert(ImportedBy);
+    ImportedBy->Imports.insert(Current);
   } else {
-    ModuleEntry->DirectlyImported = true;
+    Current->DirectlyImported = true;
   }
   
-  return std::make_pair(ModuleEntry, NewModule);
+  return *Current;
 }
 
 void ModuleManager::addInMemoryBuffer(StringRef FileName, 

diff --git a/test/Modules/Inputs/diamond_bottom.h b/test/Modules/Inputs/diamond_bottom.h
deleted file mode 100644 (file)
index 40afc9b..0000000
--- a/test/Modules/Inputs/diamond_bottom.h
+++ /dev/null
@@ -1 +0,0 @@
-char bottom(char *x);

diff --git a/test/Modules/Inputs/diamond_left.h b/test/Modules/Inputs/diamond_left.h
deleted file mode 100644 (file)
index dfdd803..0000000
--- a/test/Modules/Inputs/diamond_left.h
+++ /dev/null
@@ -1 +0,0 @@
-float left(float *);

diff --git a/test/Modules/Inputs/diamond_right.h b/test/Modules/Inputs/diamond_right.h
deleted file mode 100644 (file)
index bbed7ec..0000000
--- a/test/Modules/Inputs/diamond_right.h
+++ /dev/null
@@ -1 +0,0 @@
-double right(double *);

diff --git a/test/Modules/Inputs/diamond_top.h b/test/Modules/Inputs/diamond_top.h
deleted file mode 100644 (file)
index 189687a..0000000
--- a/test/Modules/Inputs/diamond_top.h
+++ /dev/null
@@ -1 +0,0 @@
-int top(int *);

diff --git a/test/Modules/diamond.c b/test/Modules/diamond.c
deleted file mode 100644 (file)
index fdec7b3..0000000
--- a/test/Modules/diamond.c
+++ /dev/null
@@ -1,14 +0,0 @@
-// in diamond-bottom.h: expected-note{{passing argument to parameter 'x' here}}
-void test_diamond(int i, float f, double d, char c) {
-  top(&i);
-  left(&f);
-  right(&d);
-  bottom(&c);
-  bottom(&d); // expected-warning{{incompatible pointer types passing 'double *' to parameter of type 'char *'}}
-}
-
-// RUN: %clang_cc1 -emit-pch -o %t_top.h.pch %S/Inputs/diamond_top.h
-// RUN: %clang_cc1 -import-module %t_top.h.pch -emit-pch -o %t_left.h.pch %S/Inputs/diamond_left.h
-// RUN: %clang_cc1 -import-module %t_top.h.pch -emit-pch -o %t_right.h.pch %S/Inputs/diamond_right.h
-// RUN: %clang_cc1 -import-module %t_left.h.pch -import-module %t_right.h.pch -emit-pch -o %t_bottom.h.pch %S/Inputs/diamond_bottom.h
-// RUN: %clang_cc1 -import-module %t_bottom.h.pch -verify %s