[PATCH] Add extended mnemonics for bctar. Fix setting of 'at' branch hints.

[Peter Bergner]

On 4/4/19 7:49 AM, Alan Modra wrote:
> On Wed, Apr 03, 2019 at 03:54:56PM -0500, Peter Bergner wrote:
>> Anton complained that the bctar instruction was missing extended mnemonics
>> to make reading disassembly more readable.  In the process of adding that
>> support, I noticed that we were not correctly setting 'at' branch hints
>> for many branches.  Instead, we were incorrectly setting the 1-bit 'y'
>> branch hint, which wasn't correct on anything POWER4 and later.
>>
>> The patch below adds the missing bctar extended mnemonics as well as
>> now correctly setting and extracting 'at' branch hints.  The patch
>> flagged some illegal tests within the a2.[ds] tests, so I fixed those
>> to use legal operand values.
>>
>> This passed testing with no errors.  I plan on committing this tomorrow.
> 
> So I wrote another testcase to check all the possible BO bits with
> bc, bcctr, bclr and bctar, and noticed we have some problems remaining
> with disassembly of insns using 'y' hints.  I'll commit the testcase
> and fixes after your patch goes in.

Ok, I committed my patch.  I'll be interested in seeing the other
issues you've discovered.

Peter