[ARC] Add SJLI support.

[ARC] Add SJLI support.

gcc/
2018-01-26  Claudiu Zissulescu  <claziss@synopsys.com>

        * config/arc/arc-protos.h: Add arc_is_secure_call_p proto.
        * config/arc/arc.c (arc_handle_secure_attribute): New function.
        (arc_attribute_table): Add 'secure_call' attribute.
        (arc_print_operand): Print secure call operand.
        (arc_function_ok_for_sibcall): Don't optimize tail calls when
        secure.
        (arc_is_secure_call_p): New function.
        * config/arc/arc.md (call_i): Add support for sjli instruction.
        (call_value_i): Likewise.
        * config/arc/constraints.md (Csc): New constraint.

From-SVN: r257082