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

From: Nicolas Pitre
Date: Tue Nov 12 2013 - 09:32:14 EST


On Tue, 12 Nov 2013, Ben Dooks wrote:

> Given these are single instructoins for ARM, is it possible we could
> make a table of all the callers and fix them up when we initialise
> as we do for the SMP/UP case and for page-offset?

Not really. Calls to those functions are generated by the compiler
implicitly when a divisor operand is used and therefore we cannot
annotate those calls. We'd have to use special accessors everywhere to
replace the standard division operand (like we do for 64 by 32 bit
divisions) but I doubt that people would accept that.

You cannot just scan the binary for the appropriate branch opcode either
as you may turn up false positives in literal pools.


Nicolas
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