ppr_reg_float :: Int -> PtrString
ppr_reg_float i = case i of
        16 -> sLit "%xmm0" ;   17 -> sLit "%xmm1"
        18 -> sLit "%xmm2" ;   19 -> sLit "%xmm3"
        20 -> sLit "%xmm4" ;   21 -> sLit "%xmm5"
        22 -> sLit "%xmm6" ;   23 -> sLit "%xmm7"
        24 -> sLit "%xmm8" ;   25 -> sLit "%xmm9"
        26 -> sLit "%xmm10";   27 -> sLit "%xmm11"
        28 -> sLit "%xmm12";   29 -> sLit "%xmm13"
        30 -> sLit "%xmm14";   31 -> sLit "%xmm15"
        _  -> sLit "very naughty x86 register"
ppr_reg_float :: Int -> PtrString
ppr_reg_float i = case i of
        16 -> sLit "%xmm0" ;   17 -> sLit "%xmm1"
        18 -> sLit "%xmm2" ;   19 -> sLit "%xmm3"
        20 -> sLit "%xmm4" ;   21 -> sLit "%xmm5"
        22 -> sLit "%xmm6" ;   23 -> sLit "%xmm7"
        24 -> sLit "%xmm8" ;   25 -> sLit "%xmm9"
        26 -> sLit "%xmm10";   27 -> sLit "%xmm11"
        28 -> sLit "%xmm12";   29 -> sLit "%xmm13"
        30 -> sLit "%xmm14";   31 -> sLit "%xmm15"
        _  -> sLit "very naughty x86 register"
ppr_reg_float i = case i of
        16 -> sLit "%xmm0" ;   17 -> sLit "%xmm1"
        18 -> sLit "%xmm2" ;   19 -> sLit "%xmm3"
        20 -> sLit "%xmm4" ;   21 -> sLit "%xmm5"
        22 -> sLit "%xmm6" ;   23 -> sLit "%xmm7"
        24 -> sLit "%xmm8" ;   25 -> sLit "%xmm9"
        26 -> sLit "%xmm10";   27 -> sLit "%xmm11"
        28 -> sLit "%xmm12";   29 -> sLit "%xmm13"
        30 -> sLit "%xmm14";   31 -> sLit "%xmm15"
        _  -> sLit "very naughty x86 register"