llvm-6502/lib/Support
Rafael Espindola e08aac49ea Use mkdir instead of stat+mkdir.
This is an optimistic version of create_diretories: it tries to create the
directory first and looks at the parent only if that fails.

Running strace on "mkdir -p" shows that it is pessimistic, calling mkdir on
every element of the path. We could implement that if needed.

In any case, with both strategies there is no reason to call stat, just check
the return of mkdir.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201347 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-13 16:58:19 +00:00
..
Unix Remove dead code. 2014-02-13 13:45:45 +00:00
Windows Remove dead code. 2014-02-13 13:45:45 +00:00
Allocator.cpp [BumpPtrAllocator] Move DefaultSlabAllocator to a member of BumpPtrAllocator, instead of a static variable. 2013-08-28 01:02:21 +00:00
APFloat.cpp Fix known typos 2014-01-24 17:20:08 +00:00
APInt.cpp Fix known typos 2014-01-24 17:20:08 +00:00
APSInt.cpp
ARMBuildAttrs.cpp ARM: update build attributes for ABI r2.09 2014-01-19 08:25:35 +00:00
Atomic.cpp
BlockFrequency.cpp [block-freq] Add a right shift to BlockFrequency that saturates at 1. 2013-12-14 02:24:22 +00:00
BranchProbability.cpp
circular_raw_ostream.cpp
CMakeLists.txt [CMake] LLVMSupport should be responsible to provide system_libs. 2014-02-10 10:52:19 +00:00
CommandLine.cpp Fix an invalid check for duplicate option categories. 2014-02-07 17:42:30 +00:00
Compression.cpp Expose CRC-32 implementation from zlib 2013-08-14 16:03:29 +00:00
ConstantRange.cpp [ConstantRange] improve my previous patch per Nick suggestion 2013-10-31 19:53:53 +00:00
ConvertUTF.c
ConvertUTFWrapper.cpp [Support] Add a Unicode conversion wrapper from UTF16 to UTF8 2013-07-16 17:14:33 +00:00
COPYRIGHT.regex
CrashRecoveryContext.cpp Rename Windows.h to WindowsSupport.h to avoid ambiguity 2014-02-12 21:26:20 +00:00
DAGDeltaAlgorithm.cpp
DataExtractor.cpp
DataStream.cpp Add a wrapper for open. 2013-07-16 19:44:17 +00:00
Debug.cpp
DeltaAlgorithm.cpp
Disassembler.cpp Remove some std stream usage from Support and TableGen 2013-08-06 22:51:21 +00:00
Dwarf.cpp Dwarf: Fix a copy-paste bug. 2013-12-22 10:23:23 +00:00
DynamicLibrary.cpp Re-sort all of the includes with ./utils/sort_includes.py so that 2014-01-07 11:48:04 +00:00
Errno.cpp Fix some rather confusing indentation and control flow in the errno 2013-09-02 05:55:10 +00:00
ErrorHandling.cpp Roll back the ConstStringRef change for now 2014-01-27 05:24:39 +00:00
FileOutputBuffer.cpp Use the simpler version of sys::fs::remove when possible. 2014-01-10 21:40:29 +00:00
FileUtilities.cpp MemoryBuffer::getFile handles zero sized files, no need to duplicate the test. 2013-07-10 17:30:39 +00:00
FoldingSet.cpp
FormattedStream.cpp
GraphWriter.cpp Use the simpler version of sys::fs::remove when possible. 2014-01-10 21:40:29 +00:00
Hashing.cpp
Host.cpp Add support for krait cpu in llvm::sys::getHostCPUName() 2013-12-20 09:24:13 +00:00
IncludeFile.cpp
IntEqClasses.cpp
IntervalMap.cpp
IntrusiveRefCntPtr.cpp
IsInf.cpp
IsNAN.cpp
LineIterator.cpp Use two variables here rather than reusing (and abusing) one. This is 2013-12-27 04:44:35 +00:00
LLVMBuild.txt
Locale.cpp Move generic isPrint and columnWidth implementations to a separate header/source to allow using both generic and system-dependent versions on win32. 2013-09-04 16:00:12 +00:00
LockFileManager.cpp Use simpler version of sys::fs::exists when possible. 2014-02-13 04:00:35 +00:00
Makefile
ManagedStatic.cpp
MD5.cpp
Memory.cpp
MemoryBuffer.cpp MemoryBuffer: Increase the alignment of small file buffers to 16 2013-12-16 18:18:12 +00:00
MemoryObject.cpp
Mutex.cpp Remove unnecessary call to pthread_mutexattr_setpshared() 2014-01-29 00:20:44 +00:00
Path.cpp Use mkdir instead of stat+mkdir. 2014-02-13 16:58:19 +00:00
PluginLoader.cpp
PrettyStackTrace.cpp Re-sort all of the includes with ./utils/sort_includes.py so that 2014-01-07 11:48:04 +00:00
Process.cpp Hopefully fixing the MinGW 32 build, which was broken by r200767. Not using rand_s() since MinGW does not have an implementation for it, but instead using the underlying CryptGenRandom APIs. 2014-02-11 02:47:33 +00:00
Program.cpp Add non-blocking Wait() for launched processes 2013-10-01 14:28:18 +00:00
raw_os_ostream.cpp
raw_ostream.cpp raw_fd_ostream: Don't change STDERR to O_BINARY, or w*printf() (in assert()) would barf wide chars after llvm::errs(). 2014-01-12 16:14:24 +00:00
README.txt.system
regcclass.h
regcname.h
regcomp.c Fix known typos 2014-01-24 17:20:08 +00:00
regengine.inc
regerror.c
regex2.h
regex_impl.h
Regex.cpp Make llvm::Regex non-copyable but movable. 2014-01-02 19:04:59 +00:00
regexec.c
regfree.c
regstrlcpy.c
regutils.h
RWMutex.cpp
SearchForAddressOfSpecialSymbol.cpp
Signals.cpp
SmallPtrSet.cpp Rename the non-templated base class of SmallPtrSet to 2014-02-03 11:24:18 +00:00
SmallVector.cpp
SourceMgr.cpp SourceMgr diagnotics printing: fix a bug where printing a fixit for a source 2013-09-27 21:24:36 +00:00
Statistic.cpp
StreamableMemoryObject.cpp
StringExtras.cpp
StringMap.cpp
StringPool.cpp
StringRef.cpp Add {start,end}with_lower methods to StringRef. 2013-10-30 18:32:26 +00:00
StringRefMemoryObject.cpp
system_error.cpp
SystemUtils.cpp Move PrependMainExecutablePath next to its only user. 2013-06-14 15:12:13 +00:00
TargetRegistry.cpp Fix pr18235. 2013-12-13 16:05:32 +00:00
Threading.cpp Rename Windows.h to WindowsSupport.h to avoid ambiguity 2014-02-12 21:26:20 +00:00
ThreadLocal.cpp Silence g++ 4.9 build issue 2013-12-31 03:16:55 +00:00
Timer.cpp Add a wrapper for open. 2013-07-16 19:44:17 +00:00
TimeValue.cpp
ToolOutputFile.cpp Use the simpler version of sys::fs::remove when possible. 2014-01-10 21:40:29 +00:00
Triple.cpp [x86] Support i386-*-*-code16 triple for emitting 16-bit code 2014-01-20 12:02:25 +00:00
Twine.cpp
Unicode.cpp Move generic isPrint and columnWidth implementations to a separate header/source to allow using both generic and system-dependent versions on win32. 2013-09-04 16:00:12 +00:00
Valgrind.cpp
Watchdog.cpp
YAMLParser.cpp [weak vtables] Remove a bunch of weak vtables 2013-11-19 00:57:56 +00:00
YAMLTraits.cpp Re-sort all of the includes with ./utils/sort_includes.py so that 2014-01-07 11:48:04 +00:00

Design Of lib/System
====================

The software in this directory is designed to completely shield LLVM from any
and all operating system specific functionality. It is not intended to be a
complete operating system wrapper (such as ACE), but only to provide the
functionality necessary to support LLVM.

The software located here, of necessity, has very specific and stringent design
rules. Violation of these rules means that cracks in the shield could form and
the primary goal of the library is defeated. By consistently using this library,
LLVM becomes more easily ported to new platforms since the only thing requiring
porting is this library.

Complete documentation for the library can be found in the file:
  llvm/docs/SystemLibrary.html
or at this URL:
  http://llvm.org/docs/SystemLibrary.html

While we recommend that you read the more detailed documentation, for the
impatient, here's a high level summary of the library's requirements.

 1. No system header files are to be exposed through the interface.
 2. Std C++ and Std C header files are okay to be exposed through the interface.
 3. No exposed system-specific functions.
 4. No exposed system-specific data.
 5. Data in lib/System classes must use only simple C++ intrinsic types.
 6. Errors are handled by returning "true" and setting an optional std::string
 7. Library must not throw any exceptions, period.
 8. Interface functions must not have throw() specifications.
 9. No duplicate function impementations are permitted within an operating
    system class.

To accomplish these requirements, the library has numerous design criteria that
must be satisfied. Here's a high level summary of the library's design criteria:

 1. No unused functionality (only what LLVM needs)
 2. High-Level Interfaces
 3. Use Opaque Classes
 4. Common Implementations
 5. Multiple Implementations
 6. Minimize Memory Allocation
 7. No Virtual Methods