[RISC-V] pc is not increased after execute ecall

[cla7aye15I4nd]

I am trying to simulate a simple riscv helloworld example and hook the syscall, but it seems like the uc2 do not increase the pc after executing ecall.

Here is my uc code:

import lief

from capstone import Cs, CS_ARCH_RISCV, CS_MODE_RISCV64

from unicorn.riscv_const import *
from unicorn import Uc, UC_ARCH_RISCV, UC_MODE_RISCV64, UC_HOOK_INTR

uc = Uc(UC_ARCH_RISCV, UC_MODE_RISCV64)
cs = Cs(CS_ARCH_RISCV, CS_MODE_RISCV64)

elf = lief.parse('hello')
code = bytearray(elf.get_section('.text').content)

uc.mem_map(0, 0x100000)
uc.mem_write(elf.entrypoint, bytes(code) + b'hello world\n!')

def hook_intr(uc, intno, user_data):
    print(f'Interrupt number: {intno} (pc = {hex(uc.reg_read(UC_RISCV_REG_PC))})')

for i in cs.disasm(code, elf.entrypoint):
    print("0x%x:\t%s\t%s" %(i.address, i.mnemonic, i.op_str))
    
uc.hook_add(UC_HOOK_INTR, hook_intr)
uc.emu_start(elf.entrypoint, 0, count=10)

and this is my riscv code:

.global _start

_start: addi  a0, x0, 1
        la    a1, helloworld
        addi  a2, x0, 13    
        addi  a7, x0, 64    
        ecall
        addi    a0, x0, 0
        addi    a7, x0, 93
        ecall

.data
helloworld:      .ascii "Hello RISCV!\n"

The output of the simulation is:

0x100b0:	addi	a0, zero, 1
0x100b4:	auipc	a1, 1
0x100b8:	addi	a1, a1, 0x20
0x100bc:	addi	a2, zero, 0xd
0x100c0:	addi	a7, zero, 0x40
0x100c4:	ecall	
0x100c8:	mv	a0, zero
0x100cc:	addi	a7, zero, 0x5d
0x100d0:	ecall	
Interrupt number: 8 (pc = 0x100c4)
Interrupt number: 8 (pc = 0x100c4)
Interrupt number: 8 (pc = 0x100c4)
Interrupt number: 8 (pc = 0x100c4)
Interrupt number: 8 (pc = 0x100c4)

We can find that the ecall has been executed, but the pc has not increased.

[wtdcode]

FIxed in 67e2386