* real.c (real_hash): New.
        * real.h: Declare it.
        * cse.c (canon_hash): Use it.
        * cselib.c (hash_rtx): Likewise.
        * emit-rtl.c (const_double_htab_hash): Likewise.
        * rtl.h (CONST_DOUBLE_REAL_VALUE): New.
        * varasm.c (struct rtx_const): Reduce vector size; separate
        integer and fp vectors.
        (HASHBITS): Remove.
        (const_hash_1): Rename from const_hash.  Use real_hash.  Do not
        take modulus MAX_HASH_TABLE.
        (const_hash): New.  Do take modulus MAX_HASH_TABLE.
        (output_constant_def): Do not take modulus MAX_HASH_TABLE.
        (SYMHASH): Don't use HASHBITS.
        (decode_rtx_const): Copy only active bits from REAL_VALUE_TYPE.
        Fix CONST_VECTOR thinko wrt fp vectors.  Fix kind comparison.
        (simplify_subtraction): Fix kind comparison.
        (const_hash_rtx): Return unsigned int.  Don't use HASHBITS.
        Use a union to pun integer array.
        * config/rs6000/rs6000.c (rs6000_hash_constant): Use real_hash;
        only hash two words of integral CONST_DOUBLE.

From-SVN: r57356