Possible RISC-V Vector Instructions missing
Hi Vector Team,
I’m new to RISC-V and the Vector extensions, so forgive me if I’ve missed something.
I have searched the specs, emails and git hub issues, but not found anything on this:
While writing some vector code using the vector intrinsics, I noticed some instructions missing that I expected to see:
I noticed there is no saturated reverse subtract version of vssub_vx, e.g. vsrsub_vx (or should it be vrssub_vx ?) and so no vsneg_v pseudo instructions
But there are the following integer/float reverse subtract instructions:
and their pseudo instruction counterparts:
For orthogonality there should be saturated versions of the above, but maybe there is not enough encoding space?
Or possibly remove vrsub_vx & vfrsub_vf to gain encoding space ??
Note: I wanted to use vsrsub_vx (to do vsneg_v), but instead achieved it by loading a vector with zero and performing vssub_vv.
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