Question on movsi and movdi

[Henri Cloetens]

Hello All,

I have a question on move si and move di.

I have a target, which is essentially a 32-bit processor, but it has a 
64-bit load and store instruction.

Now, there is a
define_insn movsi,
and that's all nice and fancy and working, but I also need a define_insn 
movdi.
Simplified, it looks as follows:

(define_insn "movdi"
 Â  [(set (match_operand:DI 0 "blueproc_nonimmediate_operand" "=r,r,m")
 Â Â Â Â Â Â Â  (match_operand:DI 1 "input_operand" "r,m,r"))]

- The options 2 (m to r) and 3 (r to m), that is clear.
- The option 1 (r to r), the processor has no instruction for it. It 
needs to be translated to
 Â Â  2x the movsi instruction. Now, I would prefer to avoid duplicating 
the code written under the
 Â Â  'movsi', and call the movsi definition.
 Â Â  Q. Is this possible ?.
 Â Â Â Â  I mean, I found it can be done with define_split, but then the 
compiler gets confused, splits the
 Â Â Â Â  instruction, and cannot do the rename any more to avoid the copying.
 Â Â Â Â  (There are cases where it should rename, and cases where it should 
copy.) So, it should be done
 Â Â Â Â  in the define_insn, but I find no way to do it.

Best Regards,

Henri.