Wean LookupSubframeworkHeader off std::strings, use the new SmallString

class instead.  SmallString allows to code to avoid hitting malloc in
the normal case (or will, when some other stuff is converted over).

llvm-svn: 39084

clang/Basic/FileManager.cpp

@@ -33,11 +33,10 @@ using namespace clang;
 /// getDirectory - Lookup, cache, and verify the specified directory.  This
 /// returns null if the directory doesn't exist.
 /// 
-const DirectoryEntry *FileManager::getDirectory(const std::string &Filename) {
+const DirectoryEntry *FileManager::getDirectory(const char *FileStart,
+                                                const char *FileEnd) {
   ++NumDirLookups;
-  
-  DirectoryEntry *&NamedDirEnt =
-    DirEntries.GetOrCreateValue(&Filename[0], &Filename[0] + Filename.size());
+  DirectoryEntry *&NamedDirEnt =DirEntries.GetOrCreateValue(FileStart, FileEnd);
   
   // See if there is already an entry in the map.
   if (NamedDirEnt)
@@ -48,10 +47,14 @@ const DirectoryEntry *FileManager::getDirectory(const std::string &Filename) {
   // By default, initialize it to invalid.
   NamedDirEnt = NON_EXISTANT_DIR;
   
+  // Get the null-terminated directory name as stored as the key of the
+  // DirEntries map.
+  const char *InterndDirName = DirEntries.GetKeyForValueInMap(NamedDirEnt);
+  
   // Check to see if the directory exists.
   struct stat StatBuf;
-  if (stat(Filename.c_str(), &StatBuf) ||   // Error stat'ing.
-      !S_ISDIR(StatBuf.st_mode))            // Not a directory?
+  if (stat(InterndDirName, &StatBuf) ||   // Error stat'ing.
+      !S_ISDIR(StatBuf.st_mode))          // Not a directory?
     return 0;
   
   // It exists.  See if we have already opened a directory with the same inode.
@@ -64,7 +67,7 @@ const DirectoryEntry *FileManager::getDirectory(const std::string &Filename) {
   
   // Otherwise, we don't have this directory yet, add it.  We use the string
   // key from the DirEntries map as the string.
-  UDE.Name  = DirEntries.GetKeyForValueInMap(NamedDirEnt);
+  UDE.Name  = InterndDirName;
   return NamedDirEnt = &UDE;
 }
 

clang/Lex/HeaderSearch.cpp

@@ -15,6 +15,7 @@
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/IdentifierTable.h"
 #include "llvm/System/Path.h"
+#include "llvm/ADT/SmallString.h"
 #include <iostream>
 using namespace llvm;
 using namespace clang;
@@ -197,18 +198,19 @@ LookupSubframeworkHeader(const std::string &Filename,
   if (FrameworkPos == 0)
     return 0;
   
-  std::string FrameworkName(ContextName, FrameworkPos+strlen(".framework/"));
+  SmallString<1024> FrameworkName(ContextName, 
+                                  FrameworkPos+strlen(".framework/"));
 
   // Append Frameworks/HIToolbox.framework/
   FrameworkName += "Frameworks/";
-  FrameworkName += std::string(Filename.begin(), Filename.begin()+SlashPos);
+  FrameworkName.append(Filename.begin(), Filename.begin()+SlashPos);
   FrameworkName += ".framework/";
 
   const DirectoryEntry *&CacheLookup =
     FrameworkMap[std::string(Filename.begin(), Filename.begin()+SlashPos)];
   
   // Some other location?
-  if (CacheLookup && CacheLookup->getName() != FrameworkName)
+  if (CacheLookup && strcmp(CacheLookup->getName(), FrameworkName.c_str()) != 0)
     return 0;
   
   // Cache subframework.
@@ -216,7 +218,8 @@ LookupSubframeworkHeader(const std::string &Filename,
     ++NumSubFrameworkLookups;
     
     // If the framework dir doesn't exist, we fail.
-    const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName);
+    const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName.begin(),
+                                                     FrameworkName.end());
     if (Dir == 0) return 0;
     
     // Otherwise, if it does, remember that this is the right direntry for this
@@ -227,14 +230,17 @@ LookupSubframeworkHeader(const std::string &Filename,
   const FileEntry *FE = 0;
 
   // Check ".../Frameworks/HIToolbox.framework/Headers/HIToolbox.h"
-  std::string HeadersFilename = FrameworkName + "Headers/" +
-    std::string(Filename.begin()+SlashPos+1, Filename.end());
-  if (!(FE = FileMgr.getFile(HeadersFilename))) {
+  SmallString<1024> HeadersFilename(FrameworkName);
+  HeadersFilename += "Headers/";
+  HeadersFilename.append(Filename.begin()+SlashPos+1, Filename.end());
+  if (!(FE = FileMgr.getFile(HeadersFilename.begin(),
+                             HeadersFilename.end()))) {
     
     // Check ".../Frameworks/HIToolbox.framework/PrivateHeaders/HIToolbox.h"
-    std::string PrivateHeadersFilename = FrameworkName + "PrivateHeaders/" +
-      std::string(Filename.begin()+SlashPos+1, Filename.end());
-    if (!(FE = FileMgr.getFile(PrivateHeadersFilename)))
+    HeadersFilename = FrameworkName;
+    HeadersFilename += "PrivateHeaders/";
+    HeadersFilename.append(Filename.begin()+SlashPos+1, Filename.end());
+    if (!(FE = FileMgr.getFile(HeadersFilename.begin(), HeadersFilename.end())))
       return 0;
   }
   

clang/include/clang/Basic/FileManager.h

@@ -90,12 +90,19 @@ public:
   /// getDirectory - Lookup, cache, and verify the specified directory.  This
   /// returns null if the directory doesn't exist.
   /// 
-  const DirectoryEntry *getDirectory(const std::string &Filename);
+  const DirectoryEntry *getDirectory(const std::string &Filename) {
+    return getDirectory(&Filename[0], &Filename[0] + Filename.size());
+  }
+  const DirectoryEntry *getDirectory(const char *FileStart,const char *FileEnd);
   
   /// getFile - Lookup, cache, and verify the specified file.  This returns null
   /// if the file doesn't exist.
   /// 
   const FileEntry *getFile(const std::string &Filename);
+  const FileEntry *getFile(const char *FilenameStart,
+                           const char *FilenameEnd) {
+    return getFile(std::string(FilenameStart, FilenameEnd));
+  }
   
   void PrintStats() const;
 };