alpha.md: Add names for all unnamed insns; use define_insn_and_split in some obvious...

alpha.md: Add names for all unnamed insns; use define_insn_and_split in some obvious places.

        * config/alpha/alpha.md: Add names for all unnamed insns; use
        define_insn_and_split in some obvious places.
        (lda): Remove.
        (zero_extendqihi2): Use an expander w/ nonimmediate_operand for BWX.
        (zero_extendqisi2, zero_extendqidi2): Likewise.
        (zero_extendhisi2, zero_extendhidi2): Likewise.
        (abs splitters): Fix match_scratch operand number.
        (bcc_reverse): Swap pc & label instead of non-canonical compare.

From-SVN: r37028