PTO-ARCH-DATA-TYPES-FORMAT-E8M0

1// PTO-UNIT: {"id":"PTO-ARCH-DATA-TYPES-FORMAT-E8M0","surface":"arch","classification":["data-types","formats","e8m0"],"depends_on":["PTO-ARCH-DATA-TYPES-FORMAT-DESCRIPTOR"]}2// DOC-BEGIN: operation3// PTO-REQ-HARDWARE-NUMERIC-001: exact E8M0 power-of-two scale.4
5pure func E8M0NumericFormatDescriptor() => NumericFormatDescriptor6begin7    return NumericFormatDescriptor {8        available = TRUE, kind = NumericFormatKind_E8M0,9        carrier_bits = 8, lane_bits = 8, lanes_per_carrier = 1,10        sign_bits = 0, sign_bit = 0,11        exponent_bits_min = 8, exponent_bits_max = 8,12        fraction_bits_min = 0, fraction_bits_max = 0,13        exponent_bias_available = TRUE, exponent_bias = 127,14        required_low_zero_bits = 0, required_high_zero_bits = 0,15        has_zero = FALSE, has_signed_zero = FALSE, has_subnormal = FALSE,16        has_infinity = FALSE, has_quiet_nan = TRUE,17        has_signaling_nan = FALSE18    };19end;20
21pure func E8M0FiniteDecomposition(value: bits(8))22    => (boolean, boolean, Word, integer {-1074..1023})23begin24    if value == Ones{8} then25        return (FALSE, FALSE, Zeros{PTO_XLEN}, 0);26    else return (TRUE, FALSE, Zeros{PTO_XLEN} + 1,27                 (UInt(value) - 127) as integer {-1074..1023});28    end;29end;30
31pure func HardwareNumericScaleBlockElements() => integer {32}32begin33    return 32;34end;35pure func ClassifyE8M0(value: bits(8)) => NumericValueClass36begin37    if value == Ones{8} then return NumericValue_QuietNaN;38    else return NumericValue_PositiveNormal;39    end;40end;41
42pure func E8M0CanonicalNaN() => Word43begin44    return Zeros{PTO_XLEN} + 0xff;45end;46// DOC-END: operation47