Expected Behavior of rv64mi-p-illegal ISA Test

[kathlenehurt-sifive]

I am not sure what the expected behavior should be for this section of the rv64mi-p-illegal ISA test:

riscv-tests/isa/rv64mi/illegal.S

Lines 48 to 61 in d4eaa5b

	# Delegate supervisor software interrupts so WFI won't stall.
	csrwi mideleg, MIP_SSIP
	# Enter supervisor mode.
	la t0, 1f
	csrw mepc, t0
	li t0, MSTATUS_MPP
	csrc mstatus, t0
	li t1, (MSTATUS_MPP & -MSTATUS_MPP) * PRV_S
	csrs mstatus, t1
	mret
	1:
	# Make sure WFI doesn't trap when TW=0.
	wfi

I believe that a supervisor software interrupt should be fired, but the test fails if that happens. Should the interrupt be fired? If not, how do lines 49-56 prevent the interrupt from firing?