[Modules] Resolve top-headers of modules lazily.

This allows resolving top-header filenames of modules to FileEntries when
we need them, not eagerly.

Note that that this breaks ABI for libclang functions
clang_Module_getTopLevelHeader / clang_Module_getNumTopLevelHeaders
but this is fine because they are experimental and not widely used yet.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176975 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 15 insertions, 9 deletions

diff --git a/tools/c-index-test/c-index-test.c b/tools/c-index-test/c-index-test.c
index 46d61e995c..88b49edaaf 100644
--- a/tools/c-index-test/c-index-test.c
+++ b/tools/c-index-test/c-index-test.c
@@ -1996,12 +1996,12 @@ static int inspect_cursor_at(int argc, const char **argv) {
           unsigned i, numHeaders;
           if (mod) {
             name = clang_Module_getFullName(mod);
-            numHeaders = clang_Module_getNumTopLevelHeaders(mod);
+            numHeaders = clang_Module_getNumTopLevelHeaders(TU, mod);
             printf(" ModuleName=%s Headers(%d):",
                    clang_getCString(name), numHeaders);
             clang_disposeString(name);
             for (i = 0; i < numHeaders; ++i) {
-              CXFile file = clang_Module_getTopLevelHeader(mod, i);
+              CXFile file = clang_Module_getTopLevelHeader(TU, mod, i);
               CXString filename = clang_getFileName(file);
               printf("\n%s", clang_getCString(filename));
               clang_disposeString(filename);
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index a2449bdc3f..d63f4def29 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -5984,20 +5984,26 @@ CXString clang_Module_getFullName(CXModule CXMod) {
   return cxstring::createDup(Mod->getFullModuleName());
 }
 
-unsigned clang_Module_getNumTopLevelHeaders(CXModule CXMod) {
-  if (!CXMod)
+unsigned clang_Module_getNumTopLevelHeaders(CXTranslationUnit TU,
+                                            CXModule CXMod) {
+  if (!TU || !CXMod)
     return 0;
   Module *Mod = static_cast<Module*>(CXMod);
-  return Mod->TopHeaders.size();
+  FileManager &FileMgr = cxtu::getASTUnit(TU)->getFileManager();
+  ArrayRef<const FileEntry *> TopHeaders = Mod->getTopHeaders(FileMgr);
+  return TopHeaders.size();
 }
 
-CXFile clang_Module_getTopLevelHeader(CXModule CXMod, unsigned Index) {
-  if (!CXMod)
+CXFile clang_Module_getTopLevelHeader(CXTranslationUnit TU,
+                                      CXModule CXMod, unsigned Index) {
+  if (!TU || !CXMod)
     return 0;
   Module *Mod = static_cast<Module*>(CXMod);
+  FileManager &FileMgr = cxtu::getASTUnit(TU)->getFileManager();
 
-  if (Index < Mod->TopHeaders.size())
-    return const_cast<FileEntry *>(Mod->TopHeaders[Index]);
+  ArrayRef<const FileEntry *> TopHeaders = Mod->getTopHeaders(FileMgr);
+  if (Index < TopHeaders.size())
+    return const_cast<FileEntry *>(TopHeaders[Index]);
 
   return 0;
 }