reg-stack.c: Update comment, include varray.h.

reg-stack.c: Update comment, include varray.h.

        * reg-stack.c: Update comment, include varray.h.
        (stack_regs_mentioned_data): New global variable.
        (check_stack_regs_mentioned): New function.
        (stack_regs_mentioned): New function.
        (reg_to_stack): Initialize and free stack_regs_mentioned_data,
        use stack_regs_mentioned.
        (record_asm_reg_life): Change insn type cache for changed insn.
        (record_reg_life): Do not change the insn mode.
        (emit_pop_insn): Likewise.
        (emit_swap_insn): Likewise.
        (move_for_stack_reg): Likewise.
        (stack_reg_life_analysis): Use stack_regs_mentioned.
        (emit_swap_insn): Likewise.
        (subst_stack_regs): Likewise.
        (convert_regs): Likewise.
        * jump.c (find_cross_jump): Use stack_regs_mentioned.
        * rtl.h (stack_regs_mentioned): Declare.

From-SVN: r26360