[arm-gnu] Regarding Double Data Type Support on Cortex M4

[Carlos O'Donell]

On 6/1/2012 6:10 PM, Freddie Chopin wrote:
> W dniu 2012-06-01 21:11, Carlos O'Donell pisze:
>> Sourcery CodeBench Lite for ARM EABI does support compiling application code for the Cortex-M4F.
>>
>> The FPU on the Cortex-M4F is not a full VFP so you need to pass:
>>
>> `-mfpu=fpv4-sp-d16 -mfloat-abi=softfp`
> 
> CodeSourcery supports generating code for this chip, but it does not support the FPU... With linaro you can use:
> 
> -mfloat-abi=hard -mfpu=fpv4-sp-d16 -ffast-math
> 
> Guess which is faster (;

The best benchmark is your own application. Please don't guess :-)

Please also ensure that -ffast-math is exactly what you need since it deviates from IEEE 754.

Cheers,
Carlos.
-- 
Carlos O'Donell
Mentor Graphics / CodeSourcery
carlos_odonell at mentor.com
carlos at codesourcery.com
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