* h8300/h8300.c (h8300_adjust_insn_length): Adjust the cost of
        shifts by small constant values.
        * h8300/h8300.md: Refine comments.  Remove names from many
        patterns which don't need them.
        (compare insns): Don't underestimate lengths.
        (andqi3 expander): Remove constrains.
        (andhi3): Don't underestimate length.
        (andsi3): Don't underestimate length.  Improve code when upper
        or lower half of destination is being cleared.
        (indirect_jump_h8300, indirect_jump_h8300h): Simplify.
        (shift insns): Remove useless "I" constraint.

From-SVN: r11912