* config/i386/i386.md (bswapsi_1): Rename from bswapsi2,
        remove flags clobber.
        (bswapsi2): New expander, emit code for !TARGET_BSWAP.
        (bswaphi_lowpart): New.
        (bswapdi2): Rename from bswapdi2_rex, remove flags clobber,
        remove TARGET_BSWAP test.  Delete expander of the same name.

        * optabs.c (widen_bswap, expand_doubleword_bswap): New.
        (expand_unop): Use them.

From-SVN: r121884