Comparison operations in machine description (-1 vs +1)

[m]

Den 2019-11-12 kl. 19:54, skrev Jeff Law:
> On 11/12/19 11:29 AM, m wrote:
>> Hello gcc developers!
>>
>> I am working on a new back end for my MRISC32 ISA [1], and I'm still very
>> new to gcc internals. I suspect that I will have more questions further
>> down the road, but let's start with this topic...
>>
>> The MRISC32 ISA has instructions for setting a register based on the
>> outcome of a comparison. For instance:
>>
>>  Â  slt s1, s2, s3
>>
>> ...which is equal to (in C):
>>
>>  Â  int s1 = s2 < s3 ? -1 : 0;
> Look at STORE_FLAG_VALUE.  m68k for example works like this.
>
> jeff
>

Thanks! That did the trick!

/Marcus