llvm/lib/Support
Matthias Braun 869a1fcb64 Statistic: Bring back printing on exit by default
Turns out several external projects relied on llvm printing statistics
on exit. Let's go back to this behaviour by default and have an optional
parameter to disable it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282532 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-27 19:38:55 +00:00
..
Unix Add an c++ itanium demangler to llvm. 2016-09-06 19:16:48 +00:00
Windows Use the range variant of find/find_if instead of unpacking begin/end 2016-08-12 03:55:06 +00:00
Allocator.cpp
APFloat.cpp
APInt.cpp Missing includes. 2016-09-14 08:55:18 +00:00
APSInt.cpp
ARMBuildAttrs.cpp
ARMWinEH.cpp
Atomic.cpp
BlockFrequency.cpp
BranchProbability.cpp
CachePruning.cpp Missing includes. 2016-09-14 08:55:18 +00:00
circular_raw_ostream.cpp
CMakeLists.txt Add xxhash to llvm. 2016-09-27 15:45:57 +00:00
COM.cpp
CommandLine.cpp Revert "[Support][CommandLine] Add cl::getRegisteredSubcommands()" 2016-09-13 04:11:57 +00:00
Compression.cpp Define a dummy zlib::uncompress when zlib is not available. 2016-09-12 13:00:51 +00:00
ConvertUTF.c
ConvertUTFWrapper.cpp
COPYRIGHT.regex
CrashRecoveryContext.cpp
DAGDeltaAlgorithm.cpp
DataExtractor.cpp
DataStream.cpp
Debug.cpp
DeltaAlgorithm.cpp Missing includes. 2016-09-14 08:55:18 +00:00
Dwarf.cpp Support the DW_AT_noreturn DWARF flag. 2016-08-17 16:02:43 +00:00
DynamicLibrary.cpp
Errno.cpp
Error.cpp Missing includes. 2016-09-14 08:55:18 +00:00
ErrorHandling.cpp
FileOutputBuffer.cpp Fix a real temp file leak in FileOutputBuffer 2016-09-02 01:10:53 +00:00
FileUtilities.cpp Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes. 2016-08-23 17:14:32 +00:00
FoldingSet.cpp Replace a few more "fall through" comments with LLVM_FALLTHROUGH 2016-08-17 20:30:52 +00:00
FormattedStream.cpp
GraphWriter.cpp
Hashing.cpp
Host.cpp Properly ifdef the use of cpuid. 2016-07-20 18:54:26 +00:00
IntEqClasses.cpp
IntervalMap.cpp
IntrusiveRefCntPtr.cpp
JamCRC.cpp
LEB128.cpp
LineIterator.cpp
LLVMBuild.txt Add an c++ itanium demangler to llvm. 2016-09-06 19:16:48 +00:00
Locale.cpp
LockFileManager.cpp Missing includes. 2016-09-14 08:55:18 +00:00
ManagedStatic.cpp [ManagedStatic] Reimplement double-checked locking with std::atomic. 2016-06-29 15:04:07 +00:00
MathExtras.cpp
MD5.cpp
Memory.cpp
MemoryBuffer.cpp
MemoryObject.cpp
Mutex.cpp
Options.cpp
Path.cpp Add support for Darwin’s 64-bit universal files with 64-bit offsets and sizes for the objects. 2016-06-20 22:16:18 +00:00
PluginLoader.cpp
PrettyStackTrace.cpp
Process.cpp
Program.cpp
RandomNumberGenerator.cpp Implement getRandomBytes() function 2016-08-26 08:14:54 +00:00
raw_os_ostream.cpp
raw_ostream.cpp Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes. 2016-08-23 17:14:32 +00:00
README.txt.system
regcclass.h
regcname.h
regcomp.c
regengine.inc
regerror.c
regex2.h
regex_impl.h
Regex.cpp [Support] - Fix possible crash in match() of llvm::Regex. 2016-09-02 08:44:46 +00:00
regexec.c
regfree.c
regstrlcpy.c
regutils.h
RWMutex.cpp
ScaledNumber.cpp
ScopedPrinter.cpp
SearchForAddressOfSpecialSymbol.cpp
SHA1.cpp
Signals.cpp
SmallPtrSet.cpp Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes. 2016-08-23 17:14:32 +00:00
SmallVector.cpp
SourceMgr.cpp Remove excessive padding from LineNoCacheTy 2016-08-16 19:20:10 +00:00
SpecialCaseList.cpp
Statistic.cpp Statistic: Bring back printing on exit by default 2016-09-27 19:38:55 +00:00
StreamingMemoryObject.cpp
StringExtras.cpp
StringMap.cpp Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes. 2016-08-23 17:14:32 +00:00
StringPool.cpp
StringRef.cpp Speculative fix for build failures due to consumeInteger. 2016-09-22 15:55:05 +00:00
StringSaver.cpp
SystemUtils.cpp
TargetParser.cpp Add unittests to {ARM | AArch64}TargetParser. 2016-07-28 06:11:18 +00:00
TargetRegistry.cpp Use the range variant of find_if instead of unpacking begin/end 2016-08-12 00:18:03 +00:00
Threading.cpp
ThreadLocal.cpp
ThreadPool.cpp Removing whitespace from test commit rL273447 2016-06-22 18:01:11 +00:00
Timer.cpp
TimeValue.cpp
ToolOutputFile.cpp
Triple.cpp Triple: Add opencl environment type 2016-09-23 00:42:56 +00:00
Twine.cpp
Unicode.cpp
Valgrind.cpp
Watchdog.cpp
xxhash.cpp Add xxhash to llvm. 2016-09-27 15:45:57 +00:00
YAMLParser.cpp ADT: Add AllocatorList, and use it for yaml::Token 2016-09-11 22:40:40 +00:00
YAMLTraits.cpp [YAML] Fix YAML tags appearing before the start of sequence elements 2016-06-28 21:10:26 +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