>> The AVX10.2 ISA (Intel/AMD) appears to include conversion instructions for
>> the quarter-precision types E5M2 and E4M3 described in the “OCP 8-bit
>> Floating Point Specification”.

> Are the mantissa and exponent counts sufficient? Or do we need to describe the
> exponent bias, whether the type has non-finite numbers, etc.?

What's in a name? That which we call a rose,
By any other word would smell as sweet.

In "Intel Advanced Vector Extensions 10.2 Architecture Specification" (document number 361050-005US), the instruction mnemonics for the two types use bf8 and hf8, respectively.

It makes sense to use the term bfloat8 for "E5M2". For example, the bit representation for 1.0 in IEEE Std. 754-2019 binary16 is:


            S -E5-- ---F10----
    Binary: 0 01111 0000000000

and 1.0 in bfloat8 is:


            S -E5-- F2
    Binary: 0 01111 00

This is analogous to the relationship between IEEE binary32 and bfloat16.

As you hinted, the "E4M3" format does not have infinities (but it does have NaN).
Details are in the OCP specification, so I won't bore everyone on this list any further.

By the way, I appreciate that Shakespeare dereferenced his pointer. He wrote, "that which we call a rose", not merely "a rose". :)