--------------------------- He Liu add this ----------------------------------
This is the gem5 simulator source code.

This code is maintained for the reason that the source code provided in gem5.org 
is unable to obtained.

All files in master branch should be keeped clean, and further modification should
be implemented through adding branches.

------------------------ THE ORIGINAL README CONTENTS ------------------------

This is the gem5 simulator.

The main website can be found at http://www.gem5.org

A good starting point is http://www.gem5.org/about, and for
more information about building the simulator and getting started
please see http://www.gem5.org/documentation and
http://www.gem5.org/documentation/learning_gem5/introduction.

To build gem5, you will need the following software: g++ or clang,
Python (gem5 links in the Python interpreter), SCons, SWIG, zlib, m4,
and lastly protobuf if you want trace capture and playback
support. Please see http://www.gem5.org/documentation/general_docs/building
for more details concerning the minimum versions of the aforementioned tools.

Once you have all dependencies resolved, type 'scons
build/<ARCH>/gem5.opt' where ARCH is one of ARM, NULL, MIPS, POWER, SPARC,
or X86. This will build an optimized version of the gem5 binary (gem5.opt)
for the the specified architecture. See
http://www.gem5.org/documentation/general_docs/building for more details and
options.

The basic source release includes these subdirectories:
   - configs: example simulation configuration scripts
   - ext: less-common external packages needed to build gem5
   - src: source code of the gem5 simulator
   - system: source for some optional system software for simulated systems
   - tests: regression tests
   - util: useful utility programs and files

To run full-system simulations, you will need compiled system firmware
(console and PALcode for Alpha), kernel binaries and one or more disk
images.

If you have questions, please send mail to gem5-users@gem5.org

Enjoy using gem5 and please share your modifications and extensions.