avoiding removal of -ftrapv libcalls in RTL optimization

Ken Raeburn raeburn@raeburn.org
Mon Sep 17 08:44:00 GMT 2007


On Sep 17, 2007, at 02:47, Paolo Bonzini wrote:
>> I noticed init_optabv is used to set up sdivv_optab, which appears  
>> to be unused (and probably should be removed, but as a separate  
>> patch).
>
> sdivv would presumably abort on a division by zero.

That makes sense -- I suppose the divsi3 pattern isn't required to  
trap on division by 0? -- but from some test output at -O0 on x86, I  
don't think we even try to use it.  Not to mention the fact that the  
string "divv" isn't present in libgcc2.c at all. :)

Ken



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