# Release notes for Linux Kernel VFP support code

Date: 20 May 2004

Author: Russell King

This is the first release of the Linux Kernel VFP support code. It provides support for the exceptions bounced from VFP hardware found on ARM926EJ-S.

This release has been validated against the SoftFloat-2b library by John R. Hauser using the TestFloat-2a test suite. Details of this library and test suite can be found at:

> http://www.jhauser.us/arithmetic/SoftFloat.html

The operations which have been tested with this package are:

> - fdiv
> - fsub
> - fadd
> - fmul
> - fcmp
> - fcmpe
> - fcvtd
> - fcvts
> - fsito
> - ftosi
> - fsqrt

All the above pass softfloat tests with the following exceptions:

- fadd/fsub shows some differences in the handling of +0 / -0 results when input operands differ in signs.
- the handling of underflow exceptions is slightly different. If a result underflows before rounding, but becomes a normalised number after rounding, we do not signal an underflow exception.

Other operations which have been tested by basic assembly-only tests are:

> - fcpy
> - fabs
> - fneg
> - ftoui
> - ftosiz
> - ftouiz

The combination operations have not been tested:

> - fmac
> - fnmac
> - fmsc
> - fnmsc
> - fnmul