GCC internals - Instruction Patterns

[Jeff Law]

On 10/05/2015 10:15 PM, htio2 wrote:
> Ok, so you mean this non standard patterns is not use by compiler ?
If they start with a "*" the patterns can not be referenced by the 
compiler directly, but if code which matches the structure of those 
patterns is created, then those patterns will be used.  Examples would 
be all the *movXX_internal patterns in the v850 machine description.

A non-standard name which does not start with a "*" can be referenced by 
the target to generate code.  Since you seem to be looking at the v850 
backend, an example would be the "save_interrupt" pattern which the v850 
backend can reference via gen_save_interrupt.

All this is explained in detail in the GCC internals manual.  I 
recommend you read it carefully.

jeff