[PATCH v2] ARM: Use udiv/sdiv for __aeabi_{u}idiv library functions

Måns Rullgård mans at mansr.com
Sat Nov 9 13:20:38 EST 2013

Matt Sealey <neko at bakuhatsu.net> writes:

> BTW has there been any evaluation of the penalty for the extra
> branching, or the performance hit for the ARMv7-without-division
> cases?

The branches themselves probably have minimal overhead.  There will
however be code to preserve call-clobbered registers (and move the
values to/from r0/r1) that would not be needed if the div instructions
were done inline (obviously such a kernel could only run on hardware
with division support).

Måns Rullgård
mans at mansr.com

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