llvm-svn: 121378

llvm-svn: 120688

llvm-svn: 120297

followed by an open for every source file we open, probe the file system with
'open' and then do an fstat when it succeeds.  open+fstat is faster than
stat+open because the kernel only has to perform the string->inode mapping
once.  Presumably it gets faster the deeper in your filesystem a lookup
happens.

For -Eonly on cocoa.h, this reduces system time from 0.042s to 0.039s on
my machine, a 7.7% speedup.

llvm-svn: 120066

llvm-svn: 120061

pointer that is passed down through the APIs, and make
FileSystemStatCache::get be the one that filters out
directory lookups that hit files.  This also paves the
way to have stat queries be able to return opened files.

llvm-svn: 120060

which simplifies clients and is important for future directions.
Add a FD member to FileEntry which isn't used but will be shortly.

llvm-svn: 120056

llvm-svn: 120048

method in FileSystemStatCache.

llvm-svn: 120037

MemoryBuffer::getFile, causing us to pick up a fstat for
every file.  Restore the optimization.

llvm-svn: 120032

its own header and giving it some more structure.  No 
functionality change.

llvm-svn: 120030

two copies, since they are fundamentally different
operations and the StringRef one should go away
(it shouldn't be part of FileManager at least).

Remove some dead arguments.

llvm-svn: 120013

FileSystemOpts through a ton of apis, simplifying a lot of code.
This also fixes a latent bug in ASTUnit where it would invoke
methods on FileManager without creating one in some code paths
in cindextext.

llvm-svn: 120010

to simplify a bunch of code in it.  It should ultimately get inlined
into FileManager.

llvm-svn: 120007

This patch completely defeated the "passing in a prestat'd size 
to MemoryBuffer" optimization, leading to an extra fstat call for
every buffer opened, in order to find out if the datestamp and size 
of the file on disk matches what is in the stat cache.

I fully admit that I don't completely understand what is going on here:
why punish code when a stat cache isn't in use?  what is the point of a
stat cache if you have to turn around and stat stuff to validate it?

To resolve both these issues, just drop the modtime check and check the
file size, which is the important thing anyway.  This should also resolve
PR6812, because presumably windows is stable when it comes to file sizes.
If the modtime is actually important, we should get it and keep it on the
first stat.

This eliminates 833 fstat syscalls when processing Cocoa.h, speeding up
system time on -Eonly Cocoa.h  from 0.041 to 0.038s.

llvm-svn: 120001

llvm-svn: 119997

llvm-svn: 119995

llvm-svn: 119939

llvm-svn: 119934

When -working-directory is passed in command line, file paths are resolved relative to the specified directory.
This helps both when using libclang (where we can't require the user to actually change the working directory)
and to help reproduce test cases when the reproduction work comes along.

--FileSystemOptions is introduced which controls how file system operations are performed (currently it just contains
 the working directory value if set).
--FileSystemOptions are passed around to various interfaces that perform file operations.
--Opening & reading the content of files should be done only through FileManager. This is useful in general since
 file operations will be abstracted in the future for the reproduction mechanism.

FileSystemOptions is independent of FileManager so that we can have multiple translation units sharing the same
FileManager but with different FileSystemOptions.

Addresses rdar://8583824.

llvm-svn: 118203

#pragma once wasn't working on win32 if the header file was included
using a different case.
I tracked down  the problem to the fact that clang::FileManager was
caching files using case sensitive string (UniqueFiles) on Windows.

I changed FileManager to cache filename in lower case only.
Doesn't affect UNIX because UNIX uses Inode to uniquely identify files.

unix doesn't use this codepath.

Analysis and patch by Francois Pichet!

llvm-svn: 111866

its absolute path on disk. Also, introduce a fun test for the
precompiled preamble, which almost works...

llvm-svn: 109470

llvm-svn: 108375

llvm-svn: 91684

inconsistent situations if we do, and they are not important for PCH performance
(which currently only needs the stats to construct the initial FileManager
entries).
 - No test case, sorry, the machinations are too involved.

This occurs when, for example, the build makes a PCH file and has a header map
or a -I for a directory that does not yet exist. It is possible we will cache
the negative stat on that directory, and then in the build we will never find
header files inside that dir.

For PCH we don't need these stats anyway for performance, so this also makes PCH
files smaller w/ no loss. I hope to eventually eliminate the stat cache
entirely.

llvm-svn: 91082

file. This is accomplished by introducing the notion of a "virtual"
file into the file manager, which provides a FileEntry* for a named
file whose size and modification time are known but which may not
exist on disk.

Added a cute little test that remaps both a .c file and a .h file it
includes to alternative files.

llvm-svn: 90329

only supporting a single stat cache. The immediate benefit of this
change is that we can now generate a PCH/AST file when including
another PCH file; in the future, the chain of stat caches will likely
be useful with multiple levels of PCH files.

llvm-svn: 84263

with zeros.  This avoids a GCC warning (PR5000)

llvm-svn: 82194

llvm-svn: 81346

llvm-svn: 81079

llvm-svn: 79868

llvm-svn: 79854

llvm-svn: 78824

essentially the same thing we do with pretokenized headers. stat()
caching improves performance of the Cocoa-prefixed "Hello, World" by
45%.

llvm-svn: 70223

headers. Future approaches to (de-)serializing ASTs will be based on
the PCH infrastructure.

llvm-svn: 69828

- set the 'StatSysCallCache' object using a setter method instead of
  FileManager's constructor. This allows the cache to be installed after the
  FileManager object is created.
- Add 'file mode' to FileEntry (useful for stat caching)

llvm-svn: 64351

llvm-svn: 64348

for use by FileManager. FileManager now takes a StatSysCallCache* in its
constructor (which defaults to NULL). This will be used for evaluating whether
or not caching 'stat' system calls in PTH is a performance win. This shim adds
no observable performance impact in the case where the 'StatSysCallCache*' is
null.

llvm-svn: 64345

llvm-svn: 63162

Performance impact (clang -fsyntax-only INPUTS/Cocoa_h.m):
  non-PTH: 0.4% improvement
  PTH: 0.8% improvement

llvm-svn: 63159