Re: [PATCH 3/8] rs6000: Convert <x> built-in constraints to <x,y> form

[Bill Schmidt <wschmidt@linux.ibm.com>]

On 1/28/22 5:24 PM, Segher Boessenkool wrote:
> On Fri, Jan 28, 2022 at 11:50:21AM -0600, Bill Schmidt wrote:
>> When introducing the new built-in support, I tried to match as many
>> existing error messages as possible.  One common form was "argument X must
>> be a Y-bit unsigned literal".  Another was "argument X must be a literal
>> between X' and  Y', inclusive".  During reviews, Segher requested that I
>> eventually convert all messages of the first form into the second form for
>> consistency.  That's what this patch does, replacing all <x>-form
>> constraints (first form) with <x,y>-form constraints (second form).
> Well, I asked for the error messages to be clearer and more consistent
> like that.  I don't think changing our source code like this is an
> improvement (*we* know what a 5-bit signed number is).  Do you think
> after your patch it is clearer and we will make fewer errors?

No, I don't think the patch is a particular improvement.  It sounds like
I may have misinterpreted what you were looking for here.  Please let me
know what I might do differently.

For example, if we leave the <x> format in place in the source, I could
change the error messages that we produce to calculate the minimum and
maximum allowed values.  Then we'd still have the changes to the test
cases, but fewer changes to the source.  Thoughts?

Thanks,
Bill

>
> Segher