Emit JIT code for instructions in trace buffer on loop termination. Simplify handling of program counter.
Emit JIT code for instructions in trace buffer on loop termination. Simplify handling of program counter.

$ rv-jit build/riscv64-unknown-elf/bin/test-loop --trace

rv-jit-0.0.0-prealpha-0

trace-begin pc=0x00000000000100d4
	0x00000000000100d4	add         a0, a3, a4
		mov r8 r11
		add r8 r12
	0x00000000000100d8	ld          a0, 0(a0)
		mov r8 qword ptr [r8 + 0]
	0x00000000000100dc	addi        a4, a4, 8
		add r12 8
	0x00000000000100e0	add         a1, a1, a0
		add r9 r8
	0x00000000000100e4	bne         a4, a2, pc - 16
		cmp r12 r10
		je 1f
		mov [rbp + 0] 0x00000000000100d4
		jmp term
		1:
	0x00000000000100e8	addi        a5, a5, -1
		add r13 -1
	0x00000000000100ec	bne         a5, zero, pc - 28
		cmp r13 $0
		jne 1f
		mov [rbp + 0] 0x00000000000100f0
		jmp term
		1:
	0x00000000000100d4	addi        a4, zero, 0
		mov r12 0
		mov [rbp + 0] 0x00000000000100d4
		term:
trace-end   pc=0x00000000000100d4

total=30000000

real	0m0.025s
user	0m0.022s
sys	0m0.002s

rv8-io/rv8,rv8-io/rv8,rv8-io/rv8