VFP code to store the old context, with lazy loading of the new context
when needed.
FPU_KERN_NOCTX is missing as this is unused in the crypto code this has
been tested with, and I am unsure on the requirements of the UEFI
Runtime Services.
Reviewed by: kib
Obtained from: ABT Systeems Ltd
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D8276
The flag specifies that the block which uses FPU must be executed in
critical section, i.e. take no context switches, and does not need an
FPU save area during the execution.
It is intended to be applied around fast and short code pathes where
save area allocation is impossible or undesirable, due to context or
due to the relative cost of calculation vs. allocation.
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Many thanks to jmg for reviewing the (previous version) of the text
and providing grammar and content fixes.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
