sparc: Convert to atomic_compare_and_swap.

sparc: Convert to atomic_compare_and_swap.

        * config/sparc/constraints.md ("w"): New.
        * config/sparc/predicates.md (mem_noofs_operand): New.
        * config/sparc/sparc.c (sparc_expand_compare_and_swap_12): Make static.
        Generate the boolean result of the atomic_compare_exchange.
        (sparc_expand_compare_and_swap): New.
        * config/sparc/sync.md (atomic_compare_and_swap<I>): New.
        (atomic_compare_and_swap<I48MODE>_1): Rename from
        *sync_compare_and_swap<I48MODE>, use mem_noofs_operand.
        (*atomic_compare_and_swapdi_v8plus): Rename from
        *sync_compare_and_swapdi_v8plus, use mem_noofs_operand.
        (sync_compare_and_swap<I12MODE>): Remove.
        (sync_compare_and_swap<I48MODE>): Remove.

From-SVN: r181851