[PATCH v2] ARM: Use udiv/sdiv for __aeabi_{u}idiv library functions
Nicolas Pitre
nicolas.pitre at linaro.org
Tue Nov 12 10:20:10 EST 2013
On Tue, 12 Nov 2013, Nicolas Pitre wrote:
> On Tue, 12 Nov 2013, Måns Rullgård wrote:
>
> > It might be possible to extract this information from relocation tables.
>
> True, but only for individual .o files. Once the linker puts them
> together the information is lost, and trying to infer what the linker
> has done is insane.
>
> Filtering the compiler output to annotate idiv calls before it is
> assembled would probably be a better solution.
Another solution is to patch the call site from within __aeabi_idiv at
run time using lr. That wouldn't work in the presence of tail call
optimization though.
Again this might not be worth it and patching __aeabi_idiv instead might
be a good enough compromize.
Nicolas
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