1 files changed, 39 insertions, 19 deletions

diff --git a/contrib/llvm-project/clang/lib/Lex/HeaderSearch.cpp b/contrib/llvm-project/clang/lib/Lex/HeaderSearch.cpp
index 1df28cc07209..99c92e91aad5 100644
--- a/contrib/llvm-project/clang/lib/Lex/HeaderSearch.cpp
+++ b/contrib/llvm-project/clang/lib/Lex/HeaderSearch.cpp
@@ -164,14 +164,39 @@ std::string HeaderSearch::getPrebuiltModuleFileName(StringRef ModuleName,
   return {};
 }
 
+std::string HeaderSearch::getPrebuiltImplicitModuleFileName(Module *Module) {
+  const FileEntry *ModuleMap =
+      getModuleMap().getModuleMapFileForUniquing(Module);
+  StringRef ModuleName = Module->Name;
+  StringRef ModuleMapPath = ModuleMap->getName();
+  StringRef ModuleCacheHash = HSOpts->DisableModuleHash ? "" : getModuleHash();
+  for (const std::string &Dir : HSOpts->PrebuiltModulePaths) {
+    SmallString<256> CachePath(Dir);
+    llvm::sys::fs::make_absolute(CachePath);
+    llvm::sys::path::append(CachePath, ModuleCacheHash);
+    std::string FileName =
+        getCachedModuleFileNameImpl(ModuleName, ModuleMapPath, CachePath);
+    if (!FileName.empty() && getFileMgr().getFile(FileName))
+      return FileName;
+  }
+  return {};
+}
+
 std::string HeaderSearch::getCachedModuleFileName(StringRef ModuleName,
                                                   StringRef ModuleMapPath) {
+  return getCachedModuleFileNameImpl(ModuleName, ModuleMapPath,
+                                     getModuleCachePath());
+}
+
+std::string HeaderSearch::getCachedModuleFileNameImpl(StringRef ModuleName,
+                                                      StringRef ModuleMapPath,
+                                                      StringRef CachePath) {
   // If we don't have a module cache path or aren't supposed to use one, we
   // can't do anything.
-  if (getModuleCachePath().empty())
+  if (CachePath.empty())
     return {};
 
-  SmallString<256> Result(getModuleCachePath());
+  SmallString<256> Result(CachePath);
   llvm::sys::fs::make_absolute(Result);
 
   if (HSOpts->DisableModuleHash) {
@@ -765,8 +790,7 @@ Optional<FileEntryRef> HeaderSearch::LookupFile(
 
   // This is the header that MSVC's header search would have found.
   ModuleMap::KnownHeader MSSuggestedModule;
-  const FileEntry *MSFE_FE = nullptr;
-  StringRef MSFE_Name;
+  Optional<FileEntryRef> MSFE;
 
   // Unless disabled, check to see if the file is in the #includer's
   // directory.  This cannot be based on CurDir, because each includer could be
@@ -841,8 +865,7 @@ Optional<FileEntryRef> HeaderSearch::LookupFile(
         if (Diags.isIgnored(diag::ext_pp_include_search_ms, IncludeLoc)) {
           return FE;
         } else {
-          MSFE_FE = &FE->getFileEntry();
-          MSFE_Name = FE->getName();
+          MSFE = FE;
           if (SuggestedModule) {
             MSSuggestedModule = *SuggestedModule;
             *SuggestedModule = ModuleMap::KnownHeader();
@@ -854,9 +877,6 @@ Optional<FileEntryRef> HeaderSearch::LookupFile(
     }
   }
 
-  Optional<FileEntryRef> MSFE(MSFE_FE ? FileEntryRef(MSFE_Name, *MSFE_FE)
-                                      : Optional<FileEntryRef>());
-
   CurDir = nullptr;
 
   // If this is a system #include, ignore the user #include locs.
@@ -1167,12 +1187,12 @@ HeaderFileInfo &HeaderSearch::getFileInfo(const FileEntry *FE) {
   HeaderFileInfo *HFI = &FileInfo[FE->getUID()];
   // FIXME: Use a generation count to check whether this is really up to date.
   if (ExternalSource && !HFI->Resolved) {
-    HFI->Resolved = true;
     auto ExternalHFI = ExternalSource->GetHeaderFileInfo(FE);
-
-    HFI = &FileInfo[FE->getUID()];
-    if (ExternalHFI.External)
-      mergeHeaderFileInfo(*HFI, ExternalHFI);
+    if (ExternalHFI.IsValid) {
+      HFI->Resolved = true;
+      if (ExternalHFI.External)
+        mergeHeaderFileInfo(*HFI, ExternalHFI);
+    }
   }
 
   HFI->IsValid = true;
@@ -1199,12 +1219,12 @@ HeaderSearch::getExistingFileInfo(const FileEntry *FE,
     if (!WantExternal && (!HFI->IsValid || HFI->External))
       return nullptr;
     if (!HFI->Resolved) {
-      HFI->Resolved = true;
       auto ExternalHFI = ExternalSource->GetHeaderFileInfo(FE);
-
-      HFI = &FileInfo[FE->getUID()];
-      if (ExternalHFI.External)
-        mergeHeaderFileInfo(*HFI, ExternalHFI);
+      if (ExternalHFI.IsValid) {
+        HFI->Resolved = true;
+        if (ExternalHFI.External)
+          mergeHeaderFileInfo(*HFI, ExternalHFI);
+      }
     }
   } else if (FE->getUID() >= FileInfo.size()) {
     return nullptr;