tree 4700cb2a70cbba307c29cd9c52c5e45abd93c0d2
parent 3adf023d2a05a89f4851bd49fd6a3be78bb7f77f
author Luis R. Rodriguez <mcgrof@kernel.org> 1467137992 -0700
committer Luis R. Rodriguez <mcgrof@kernel.org> 1467246545 -0700

synth: add partially static shift right demo

This demos the use of "partially static" variables, they like
consts, however we modify them early in boot time and provide
functions that do the handy work for us. The handy work of
processing them is accomplished through kernel's alternatives.
To this end we add an example simple alternatives processing
mechanism, its architecture is rather simple given it simply relies
on the linker table with structural data, and updates it as needed.

We demo a partially static function which shifts a variable to
the right by certain amount of times, the amount of times we
shift is determined through a function passed early in boot,
and as such can be dynamic.

Without alternatives processed you'd get:

Synthetics: ps_shr(0XDEADBEEF) returns: 0xDEADBEEF

After alternatives is processed you get:

Synthetics: ps_shr(0XDEADBEEF) returns: 0x0000DEAD

Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>