|author||Roland Levillain <email@example.com>||Tue May 17 12:44:25 2016 +0000|
|committer||Roland Levillain <firstname.lastname@example.org>||Tue May 17 12:44:25 2016 +0000|
Revert "Revert "Revert "VIXL Release 1.13""" This CL is breaking one of our builds (art-read-barrier, but I'm not sure it's because of the read barrier configuration). This reverts commit 04abd6397a6d78802ac005478a6fc4ad0fb2da36. Change-Id: I5034c40f9f2cab14e18d91931564970ffdb3cd36
VIXL contains three components.
The VIXL git repository can be found on GitHub.
Changes from previous versions of VIXL can be found in the Changelog.
This software is covered by the licence described in the LICENCE file.
To build VIXL the following software is required:
A 64-bit host machine is required, implementing an LP64 data model. VIXL has been tested using GCC on AArch64 Debian, GCC and Clang on amd64 Ubuntu systems.
To run the linter stage of the tests, the following software is also required:
Refer to the ‘Usage’ section for details.
The VIXL simulator supports only those instructions that the VIXL assembler can generate. The
doc directory contains a list of supported instructions.
The VIXL simulator was developed to run on 64-bit amd64 platforms. Whilst it builds and mostly works for 32-bit x86 platforms, there are a number of floating-point operations which do not work correctly, and a number of tests fail as a result.
Your project's build system must define
-DVIXL_DEBUG) when using a VIXL library that has been built with debug enabled.
Some classes defined in VIXL header files contain fields that are only present in debug builds, so if
VIXL_DEBUG is defined when the library is built, but not defined for the header files included in your project, you will see runtime failures.
All exclusive-access instructions are supported, but the simulator cannot accurately simulate their behaviour as described in the ARMv8 Architecture Reference Manual.
__sync_synchronize()is used for this purpose.
The simulator tries to be strict, and implements the following restrictions that the ARMv8 ARM allows:
Instructions affected by these limitations:
The helper script
tools/test.py will build and run every test that is provided with VIXL, in both release and debug mode. It is a useful script for verifying that all of VIXL's dependencies are in place and that VIXL is working as it should.
By default, the
tools/test.py script runs a linter to check that the source code conforms with the code style guide, and to detect several common errors that the compiler may not warn about. This is most useful for VIXL developers. The linter has the following dependencies:
cpplint.py, as provided by Google, must be available (and executable) on the
It is possible to tell
tools/test.py to skip the linter stage by passing
--nolint. This removes the dependency on
cpplint.py and Git. The
--nolint option is implied if the VIXL project is a snapshot (with no
There are three very basic benchmarks provided with VIXL:
Build these benchmarks using
scons bench-branch and
scons bench-branch-link. This will produce binaries called
bench-branch-link_sim. Run these with an iteration count argument, for example
./bench-dataop_sim 10000000. The benchmarks do not report a result; time them using the UNIX
Build the benchmarks natively for execution on an AArch64 target using
scons <benchmark name> simulator=off. This will produce binaries called
bench-branch-link. Run and time these in the same way as the simulator versions.
A short introduction to using VIXL can be found here. Example source code is provided in the examples directory. You can build all the examples with
scons examples from the root directory, or use
scons --help to get a detailed list of available build targets.