Re: [PATCH][ARM] Fix costing of vmul+vcvt combine pattern

[Kyrill Tkachov]

Ping.
https://gcc.gnu.org/ml/gcc-patches/2015-10/msg02898.html

Thanks,
Kyrill

On 27/10/15 13:55, Kyrill Tkachov wrote:

Hi all,

This patch allows us to handle the *combine_vcvtf2i pattern in rtx costs by 
properly identifying it
as a toint coversion. Before this I saw a pattern like:
(set (reg/i:SI 0 r0)
    (fix:SI (fix:SF (mult:SF (reg:SF 16 s0 [ a ])
                (const_double:SF 3.2e+1 [0x0.8p+6])))))

being assigned a cost of 40 because the costs blindly recursed into the 
operands.
With this patch for -mcpu=cortex-a57 I see it being assigned a cost of 4.

Bootstrapped and tested on arm-none-linux-gnueabihf.

Ok for trunk?

Thanks,
Kyrill

2015-10-27  Kyrylo Tkachov  <kyrylo.tkac...@arm.com>

    * config/arm/arm.c (arm_new_rtx_costs, FIX case): Handle
    combine_vcvtf2i pattern.