Illegal Instruction overlap difference between vfwadd_wf and vwadd_wx

riscv-software-src / riscv-isa-sim

Spike, a RISC-V ISA Simulator

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Illegal Instruction overlap difference between vfwadd_wf and vwadd_wx #1766

Open FariaaFaheem opened 4 months ago

FariaaFaheem commented 4 months ago

Why is vfwadd_wf v24, v24, ft10 illegal but vwadd_wx v24, v24, x2 legal?

aswaterman commented 4 months ago

They're both legal.

I'm guessing that you either forgot to set mstatus.FS to nonzero, or you have vtype.vsew set to a value corresponding to an unsupported floating-point format.

EDIT: I now see mstatus.FS is nonzero in your code, so I'm guessing vtype.vsew is the culprit.