llvm-6502/lib/System
2004-12-09 05:51:11 +00:00
..
AIX Dynamic Library abstraction. This makes the abstraction of a single dynamic 2004-11-18 04:33:39 +00:00
Cygwin Dynamic Library abstraction. This makes the abstraction of a single dynamic 2004-11-18 04:33:39 +00:00
Darwin Dynamic Library abstraction. This makes the abstraction of a single dynamic 2004-11-18 04:33:39 +00:00
FreeBSD Dynamic Library abstraction. This makes the abstraction of a single dynamic 2004-11-18 04:33:39 +00:00
Interix Dynamic Library abstraction. This makes the abstraction of a single dynamic 2004-11-18 04:33:39 +00:00
Linux Dynamic Library abstraction. This makes the abstraction of a single dynamic 2004-11-18 04:33:39 +00:00
SunOS Dynamic Library abstraction. This makes the abstraction of a single dynamic 2004-11-18 04:33:39 +00:00
Unix Make this work with the ICC compiler, contributed by Bjørn Wennberg 2004-12-08 16:10:52 +00:00
Win32 Fix residual Visual Studio build problems 2004-12-09 05:51:11 +00:00
DynamicLibrary.cpp Fix compilation error on Darwin. 2004-12-04 04:17:20 +00:00
LICENSE.TXT
ltdl.c Mods for compilation with llvm. 2004-11-29 12:04:27 +00:00
ltdl.h Original version of ltdl.h from libtool 1.5.10 2004-11-29 12:02:48 +00:00
Makefile
MappedFile.cpp
Memory.cpp
Path.cpp Make sure IdentifyFileType is in the sys namespace. 2004-11-14 23:26:18 +00:00
Process.cpp
Program.cpp
README.txt Consistently use llvm.cs.uiuc.edu instead of llvm.org 2004-11-07 00:58:20 +00:00
Signals.cpp
SysConfig.cpp
TimeValue.cpp Don't exceed 80 columns. 2004-11-14 22:06:18 +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.cs.uiuc.edu/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 throwing std::string *only*.
 7. Library must not throw any exceptions except std::string.
 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