FP8 ACLE specification

[momchil-velikov]

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[andrewcarlotti]

I'd prefer slightly different naming for the intrinsics and new types. Specifically:

1. Can we call the new types floatm8_t, floatm8x16_t, svfloatm8_t, etc.? This would be more consistent with existing type names while still preserving the "modal" distinction. It also makes the type name more easily distinguishable from FPMR values (which use fpm_t).

2. Can we drop the _fpm suffix from all the intrinsic names, and instead represent the modality in the type suffix (by replacing _f8 with _fm8 wherever it appears)?

Combining these, my proposal is to replace, for example,
float16x4_t vdot_lane_f16_f8_fpm(float16x4_t vd, fpm8x8_t vn, fpm8x8_t vm, __builtin_constant_p(lane), fpm_t fpm)
with
float16x4_t vdot_lane_f16_fm8(float16x4_t vd, floatm8x8_t vn, floatm8x8_t vm, __builtin_constant_p(lane), fpm_t fpm).

[momchil-velikov]

1. Can we call the new types floatm8_t, floatm8x16_t, svfloatm8_t, etc.?
2. Can we drop the _fpm suffix from all the intrinsic names, and instead represent the modality in the type suffix (by replacing _f8 with _fm8 wherever it appears)?

I am in favour of both proposals.

[rsandifo-arm]

This might have been mentioned already, but the new vector types should also be added to svset_neonq, svget_neonq and svdup_neonq.

[momchil-velikov]

1. Can we call the new types floatm8_t, floatm8x16_t, svfloatm8_t, etc.?
2. Can we drop the _fpm suffix from all the intrinsic names, and instead represent the modality in the type suffix (by replacing _f8 with _fm8 wherever it appears)?

I am in favour of both proposals.

Coming up Soon(tm).

[momchil-velikov]

This might have been mentioned already, but the new vector types should also be added to svset_neonq, svget_neonq and svdup_neonq.

My next step is to add intrinsics for the untyped SVE/SME instructions, that would include these too.

[momchil-velikov]

I'd prefer slightly different naming for the intrinsics and new types. Specifically:

1. Can we call the new types floatm8_t, floatm8x16_t, svfloatm8_t, etc.? This would be more consistent with existing type names while still preserving the "modal" distinction. It also makes the type name more easily distinguishable from FPMR values (which use fpm_t).

This part done.

[paulwalker-arm]

1. Can we call the new types floatm8_t, floatm8x16_t, svfloatm8_t, etc.? This would be more consistent with existing type names while still preserving the "modal" distinction. It also makes the type name more easily distinguishable from FPMR values (which use fpm_t).

As an amendment that follows the scheme used when going from float16 -> bfloat16 what about mfloat8_t, mfloat8x16_t, svmfloat8_t with "m" meaning "modal"?

[momchil-velikov]

Things renamed according to the above naming scheme.

[rsandifo-arm]

The new feature macros should also be listed in the “Summary of predefined macros” section.