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Ping: [PATCH]Remove duplicate check on BRANCH_COST in fold-const.c


Ping.

> -----Original Message-----
> From: Richard Earnshaw
> Sent: Thursday, July 26, 2012 9:19 PM
> To: Andrew Pinski
> Cc: Bin Cheng; gcc-patches@gcc.gnu.org
> Subject: Re: [PATCH]Remove duplicate check on BRANCH_COST in fold-const.c
> 
> On 26/07/12 11:27, Andrew Pinski wrote:
> > On Thu, Jul 26, 2012 at 3:20 AM, Bin Cheng <bin.cheng@arm.com> wrote:
> >> Hi,
> >> This patch removes the duplicate check on BRANCH_COST in
fold_truth_andor.
> >> The BRANCH_COST condition removed is a duplicate of the default
> >> definition of LOGICAL_OP_NON_SHORT_CIRCUIT.
> >> All current targets (mips and rs6000) that provide non-default
> >> definitions of LOGICAL_OP_SHORT_CIRCUIT set it to 0, so this patch is
> >> therefore just a code cleanup and does not change behaviour in the
compiler.
> >>
> >> I built mipsel-elf cross compiler and compared newlib/libstdc++
> >> compiled by the patched/original compilers.
> >>
> >> Is it OK?
> >
> > Just some history here on this.  The BRANCH COST check was there
> > before LOGICAL_OP_NON_SHORT_CIRCUIT was added.  I will be submitting a
> > patch which changes the MIPS definition soon but it will not be based
> > on the branch cost but rather than another option.  So in the end it
> > might not be redundant as it is currently.
> >
> > Thanks,
> > Andrew
> >
> 
> You can always factor BRANCH_COST into LOGICAL_OP_NON_SHORT_CIRCUIT (as
the
> default currently does), so there's no loss of functionality from removing
> this currently redundant check.  However, the current definition is broken
in
> that it makes it impossible to force the compiler to use this optimization
> when the branch cost is low.
> 

Is it OK?

Thanks




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