DRI Compilation Guide : CPU Architectures
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5. CPU Architectures

In general, nothing special has to be done to use the DRI on different CPU architectures. There are, however, a few optimizations that are CPU-dependent. Mesa will determine at runtime which CPU-dependent optimizations should be used and enable them where appropriate.

5.1. Intel Pentium III Features

The Pentium III SSE (Katmai) instructions are used in optimized vertex transformation functions in the Mesa-based DRI drivers. On Linux, SSE requires a recent kernel (such as 2.4.0-test11 or later) both at compile time and runtime.

5.2. AMD 3DNow! Features

AMD's 3DNow! instructions are used in optimized vertex transformation functions in the Mesa-based DRI drivers. 3DNow! is supported in most versions of Linux.

5.3. Alpha Features

On newer Alpha processors a significant performance increase can be seen with the addition of the -mcpu= option to GCC. This option is dependent on the architecture of the processor. For example, -mcpu=ev6 will build specifically for the EV6 based AXP's, giving both byte and word alignment access to the DRI/Mesa drivers.

To enable this optimization edit your xc/config/host.def file and add the line:

#define DefaultGcc2AxpOpt -O2 -mcpu=ev6

Additional speed improvements to 3D rendering can be achieved by installing Compaq's Math Libraries (CPML) which can be obtained from http://www.support.compaq.com/alpha-tools/software/index.html

Once installed, you can add this line to your host.def to build with the CPML libraries:

#define UseCompaqMathLibrary YES

The host.def file is explained below.


DRI Compilation Guide : CPU Architectures
Previous: Linux Kernel Preparation
Next: Downloading the XFree86/DRI CVS Sources