[Bug target/65117] xtensa: With -Os, invalid parameter c1 for reg_class_subset_p() to cause segment fault.

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65117

Jeffrey A. Law <law at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2015-02-23
                 CC|                            |law at redhat dot com
     Ever confirmed|0                           |1

--- Comment #3 from Jeffrey A. Law <law at redhat dot com> ---
The problem here is the zero_cost_loop_start, zero_cost_loop_end, and loop_end
patterns in the xtensa backend are wrong.  operand 0 has a match constraint of
"2".  That's not allowed (the number in the constraint must be lower then the
operand number in which it appears).

This might be fixable by copying the constraints from operand2 to operand0,
then using "0" as the constraint for operand 2.