https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95267
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |RESOLVED
Resolution|--- |INVALID
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The internals documentation documents this even, read:
https://gcc.gnu.org/onlinedocs/gccint/RTL-Template.html#index-match_005fdup
>From that:
Note that match_dup should not be used to tell the compiler that a particular
register is being used for two operands (example: add that adds one register to
another; the second register is both an input operand and the output operand).
Use a matching constraint (see Simple Constraints) for those.
