[VFS] vfs::directory_iterator yields path and file type instead of full Status

Summary:
Most callers I can find are using only `getName()`. Type is used by the
recursive iterator.

Now we don't have to call stat() on every listed file (on most platforms).
Exceptions are e.g. Solaris where readdir() doesn't include type information.
On those platforms we'll still stat() - see D51918.

The result is significantly faster (stat() can be slow).
My motivation: this may allow us to improve clang IO on large TUs with long
include search paths. Caching readdir() results may allow us to skip many stat()
and open() operations on nonexistent files.

Reviewers: bkramer

Subscribers: fedor.sergeev, cfe-commits

Differential Revision: https://reviews.llvm.org/D51921

llvm-svn: 342232

2 files changed, 9 insertions, 9 deletions

diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index f1a8720045e..38a09a0dac3 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -185,10 +185,10 @@ static void collectIncludePCH(CompilerInstance &CI,
     // used here since we're not interested in validating the PCH at this time,
     // but only to check whether this is a file containing an AST.
     if (!ASTReader::readASTFileControlBlock(
-            Dir->getName(), FileMgr, CI.getPCHContainerReader(),
+            Dir->path(), FileMgr, CI.getPCHContainerReader(),
             /*FindModuleFileExtensions=*/false, Validator,
             /*ValidateDiagnosticOptions=*/false))
-      MDC->addFile(Dir->getName());
+      MDC->addFile(Dir->path());
   }
 }
 
diff --git a/clang/lib/Frontend/FrontendAction.cpp b/clang/lib/Frontend/FrontendAction.cpp
index 74550c41039..ddb522ae05f 100644
--- a/clang/lib/Frontend/FrontendAction.cpp
+++ b/clang/lib/Frontend/FrontendAction.cpp
@@ -347,12 +347,12 @@ static std::error_code collectModuleHeaderIncludes(
          Dir != End && !EC; Dir.increment(EC)) {
       // Check whether this entry has an extension typically associated with
       // headers.
-      if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->getName()))
-          .Cases(".h", ".H", ".hh", ".hpp", true)
-          .Default(false))
+      if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->path()))
+               .Cases(".h", ".H", ".hh", ".hpp", true)
+               .Default(false))
         continue;
 
-      const FileEntry *Header = FileMgr.getFile(Dir->getName());
+      const FileEntry *Header = FileMgr.getFile(Dir->path());
       // FIXME: This shouldn't happen unless there is a file system race. Is
       // that worth diagnosing?
       if (!Header)
@@ -365,7 +365,7 @@ static std::error_code collectModuleHeaderIncludes(
 
       // Compute the relative path from the directory to this file.
       SmallVector<StringRef, 16> Components;
-      auto PathIt = llvm::sys::path::rbegin(Dir->getName());
+      auto PathIt = llvm::sys::path::rbegin(Dir->path());
       for (int I = 0; I != Dir.level() + 1; ++I, ++PathIt)
         Components.push_back(*PathIt);
       SmallString<128> RelativeHeader(UmbrellaDir.NameAsWritten);
@@ -696,10 +696,10 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
            Dir != DirEnd && !EC; Dir.increment(EC)) {
         // Check whether this is an acceptable AST file.
         if (ASTReader::isAcceptableASTFile(
-                Dir->getName(), FileMgr, CI.getPCHContainerReader(),
+                Dir->path(), FileMgr, CI.getPCHContainerReader(),
                 CI.getLangOpts(), CI.getTargetOpts(), CI.getPreprocessorOpts(),
                 SpecificModuleCachePath)) {
-          PPOpts.ImplicitPCHInclude = Dir->getName();
+          PPOpts.ImplicitPCHInclude = Dir->path();
           Found = true;
           break;
         }