Re: [PATCH (7/7)] Mixed-sign multiplies using narrowest mode

[Richard Guenther <richard.guenther@gmail.com>]

On Thu, Jul 14, 2011 at 4:38 PM, Andrew Stubbs <ams@codesourcery.com> wrote:
> On 28/06/11 17:23, Andrew Stubbs wrote:
>>
>> On 23/06/11 15:43, Andrew Stubbs wrote:
>>>
>>> Patch 4 introduced support for using signed multiplies to code unsigned
>>> multiplies in a narrower mode. Patch 5 then introduced support for
>>> mis-matched input modes.
>>>
>>> These two combined mean that there is case where only the smaller of two
>>> inputs is unsigned, and yet it still tries to user a mode wider than the
>>> larger, signed input. This is bad because it means unnecessary extends
>>> and because the wider operation might not exist.
>>>
>>> This patch catches that case, and ensures that the smaller, unsigned
>>> input, is zero-extended to match the mode of the larger, signed input.
>>>
>>> Of course, both inputs may still have to be extended to fit the nearest
>>> available instruction, so it doesn't make a difference every time.
>>>
>>> OK?
>>
>> This update fixes Janis' issue with the testsuite.
>
> And this version is updated to fit the changes made earlier in the series,
> and also to use the precision, instead of the mode-size, in order to better
> optimize bitfields.
>
> OK?

Ok.

Thanks,
Richard.

> Andrew
>