llvm-mirror/lib/System
Mikhail Glushenkov 3b1f94a1fc Get rid of GetProcessId in Win32/Program.inc.
GetProcessId was introduced only in XP. As a bonus, this change makes Program
objects copyable, since Program is now basically a PID.

llvm-svn: 81826
2009-09-15 03:39:45 +00:00
..
Unix Get rid of GetProcessId in Win32/Program.inc. 2009-09-15 03:39:45 +00:00
Win32 Get rid of GetProcessId in Win32/Program.inc. 2009-09-15 03:39:45 +00:00
Alarm.cpp
Atomic.cpp Add atomic multiply and divide operations, built on top of CompareAndSwap. 2009-06-23 21:19:04 +00:00
CMakeLists.txt CMake: make sure that the *.inc files for libSystem show up in the resulting 2009-07-27 17:55:55 +00:00
Disassembler.cpp This void is implicit in C++. 2009-08-12 22:10:57 +00:00
DynamicLibrary.cpp Fix ExplicitSymbols leak. 2009-08-31 16:12:29 +00:00
Errno.cpp Oops, I #included errno.h from inside the llvm::sys namespace. 2009-07-06 16:50:27 +00:00
Host.cpp
IncludeFile.cpp
Makefile
Memory.cpp Experimental fix for PR4960. 2009-09-12 23:29:02 +00:00
Mutex.cpp Tweak code into an equivalent form for which icc 2009-09-06 10:53:22 +00:00
Path.cpp Prune #includes from llvm/Linker.h and llvm/System/Path.h, 2009-08-23 22:45:37 +00:00
Process.cpp
Program.cpp Remove duplication in Program::Execute{And,No}Wait. 2009-07-18 21:43:12 +00:00
README.txt
RWMutex.cpp Tweak code into an equivalent form for which icc 2009-09-06 10:53:22 +00:00
Signals.cpp
Threading.cpp No need to double-include config.h 2009-07-06 21:24:37 +00:00
ThreadLocal.cpp Try again at making this work on OpenBSD. 2009-07-01 16:19:23 +00:00
TimeValue.cpp

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</a></li>
 5. Multiple Implementations</a></li>
 6. Minimize Memory Allocation</a></li>
 7. No Virtual Methods