[cfe-dev] Performance alloca + memcpy vs alloca + inline

[Hal Finkel]

----- Original Message -----
> From: "Stefan de Konink" <stefan at konink.de>
> To: cfe-dev at cs.uiuc.edu
> Sent: Saturday, February 1, 2014 3:34:10 PM
> Subject: [cfe-dev] Performance alloca + memcpy vs alloca + inline
> 
> Hi,
> 
> While I was looking for vectorisation solutions I stumbled of a
> strange
> performance difference between clang and gcc.
> 
> The attached code can be compile with:
> 
> clang -DSINGLE -std=c99 -O3 expanding-inline-generic.c
> (poor performance > ~)

Approximately what (At least in my mail client, I see no number here)?

> 
> vs
> 
> clang -DINLINE -std=c99 -O3 expanding-inline-generic.c
> (performs fast < 1s)
> 
> 
> Using GCC 4.7/4.8 both examples have no noticible differences.

Please file a bug report (http://llvm.org/bugs/) and we'll look at it.

Thanks,
Hal

> 
> Stefan
> _______________________________________________
> cfe-dev mailing list
> cfe-dev at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev
> 

-- 
Hal Finkel
Assistant Computational Scientist
Leadership Computing Facility
Argonne National Laboratory