Visible to Intel only — GUID: eis1411548450464
Ixiasoft
Visible to Intel only — GUID: eis1411548450464
Ixiasoft
4.7. ALTFP_DIV Parameters
Parameter Name | Type | Required | Description |
---|---|---|---|
WIDTH_EXP | Integer | Yes | Specifies the precision of the exponent. If this parameter is not specified, the default is 8. The bias of the exponent is always set to (2 ^ (WIDTH_EXP - 1)) - 1, that is, 127 for single precision and 1023 for double precision. The value of WIDTH_EXP must be 8 for single precision, 11 for double precision, and a minimum of 11 for single extended precision. The value of WIDTH_EXP must be less than the value of WIDTH_MAN, and the sum of WIDTH_EXP and WIDTH_MAN must be less than 64. |
WIDTH_MAN | Integer | Yes | Specifies the precision of the mantissa. If this parameter is not specified, the default is 23. When WIDTH_EXP is 8 and the floating-point format is the single-precision format, the WIDTH_MAN value must be 23. Otherwise, the value of WIDTH_MAN must be a minimum of 31. The value of WIDTH_MAN must be greater than the value of WIDTH_EXP, and the sum of WIDTH_EXP and WIDTH_MAN must be less than 64. |
ROUNDING | String | Yes | Specifies the rounding mode. The default value is TO_NEAREST. The floating-point divider does not support other rounding modes. |
OPTIMIZE | String | No | Specifies whether to optimize for area or for speed. Values are AREA and SPEED. A value of AREA optimizes the design using less total logic utilization or resources. A value of SPEED optimizes the design for better performance. If this parameter is not specified, the default value is SPEED. |
PIPELINE | Integer | No | Specifies the number of clock cycles needed to produce the result. For the single-precision format, the latency options are 33, 14 or 6. For the double-precision format, the latency options are 61, 24 or 10. For the single-extended precision format, the value ranges from a minimum of 41 to a maximum of 61. For the low-latency option, the latency is determined from the mantissa width. For a mantissa width of 31 to 40 bits, the value is 8 or 18. For a mantissa width of 41 bits or more, the value is 10 or 24. |