[PATCH] powerpc: strstr optimization

Carlos O'Donell carlos@redhat.com
Thu May 21 16:07:00 GMT 2015


On 05/11/2015 04:19 PM, Joseph Myers wrote:
> On Mon, 11 May 2015, Steven Munroe wrote:
> 
>> I think we should move on with (commit) Raji's patch as is. 
> 
> Does the patch avoid quadratic worst case?  Quadratic performance in 
> strstr is an unambiguous regression, allowing for denial-of-service, that 
> should not be introduced on any platform (cf bug 12100).  Indeed, gnulib 
> has a configure test for quadratic strstr, so if you introduce quadratic 
> worst case then the effect will be that all applications using gnulib 
> automatically configure themselves to use gnulib's strstr and not glibc's 
> at all.
> 

We should add gnulib's test to the microbenchmarks.

c.



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