[BUG] Tracer outputs wrong source register for `fsd` instruction

Created by: colluca

Is there an existing CVA6 bug for this?

• I have searched the existing bug issues

Bug Description

I'm executing a binary which contains the following instruction (from the disassembly):

8000067c:    fef6bc27              fsd    fa5,-8(a3)

The core trace contains the following line:

4549ns     4525 M 000000008000067c 0 fef6bc27 fsd            x0, -8(a3)            a3  :0000000080000760 VA: xxxxxxxxxxxxxxxx PA: 00000080000758

The machine instruction (fef6bc27) is the same in both places, so I would expect the instruction mnemonic and operands should be the same as well.

Instead, the source register in the trace is x0 despite it being fa5 in the disassembly. I can provide the binary if required to reproduce the error.