Hi，Thanks for supporting FP8 extension. After reviewing this series of patches, I saw you define "altfmt" attribute according to "UNSPEC" enum. (define_int_attr altfmt [(UNSPEC_F8E4M3 "f8e4m3") - (UNSPEC_F8E5M2 "f8e5m2")]) + (UNSPEC_F8E5M2 "f8e5m2") + (UNSPEC_F8E4M3_SAT "f8e4m3_sat") + (UNSPEC_F8E5M2_SAT "f8e5m2_sat")])
Is it possible to add an operand to FP8 machine description pattern to specify the "altfmt" like "ta"/"ma" attribute ? By default, all other non-FP8 vector instructions have "altfmt" attribute as "INVALID_ATTRIBUTE", then, specify "altfmt" for FP8 instruction according to operand value like : 0: f8e4m3 1: f8e5m2 2: f8e5m2 ...etc. Then we can avoid creating multiple "UNPSEC" patterns which helps us save machine description patterns.
