[PATCH 2/4] The main m68k cc0 conversion

[Andreas Schwab]

On Nov 25 2019, Bernd Schmidt wrote:

> On 11/25/19 12:26 PM, Andreas Schwab wrote:
>> On Nov 24 2019, Bernd Schmidt wrote:
>> 
>>> Whew, I think I have it. One tst instruction eliminated when it
>>> shouldn't have been:
>>>
>>>         move.w %a4,%d0
>>> -       tst.b %d0
>>> -       jeq .L352
>>> +       jeq .L353
>>>
>>> And the reason - that's a movqi using move.w. The following should fix
>>> it.
>> 
>> Apparently that also fixed the testsuite regressions.
>
> I still wish I knew how you managed to reproduce those.

It's undefined behaviour, so you can get all kinds of random results.
The binary diff clearly shows the missing tstb insns.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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