def execute_bl(s, inst):
if condition_passed(s, inst.cond()):
s.rf[LR] = trim_32(s.fetch_pc() + 4)
offset = signed(sign_extend_30(inst.imm_24()) << 2)
s.rf[PC] = trim_32(s.rf[PC] + offset)
return
s.rf[PC] = s.fetch_pc() + 4
def syscall_open(s):
filename_ptr = s.rf[a0]
flags = s.rf[a1]
mode = s.rf[a2]
# convert flags from solaris to linux (necessary?)
open_flags = 0
for newlib, linux in flag_table:
if flags & newlib:
open_flags |= linux
# get the filename
filename = get_str(s, filename_ptr)
try:
# open vs. os.open(): http://stackoverflow.com/a/15039662
fd = os.open(filename, open_flags, mode)
errno = 0
except OSError as e:
print "OSError in syscall_open: errno=%d" % e.errno
fd = -1
errno = e.errno
if fd > 0:
file_descriptors[fd] = trim_32(fd)
s.rf[v0] = trim_32(fd)
def syscall_write(s):
file_ptr = s.rf[a0]
data_ptr = s.rf[a1]
nbytes = s.rf[a2]
# INST NUMBER 914
# INST NUMBER 914
if file_ptr not in file_descriptors:
s.rf[v0] = -1 # TODO: return a bad file descriptor error (9)?
return
fd = file_descriptors[file_ptr]
data = get_str(s, data_ptr, nbytes)
try:
nbytes_written = os.write(fd, data)
errno = 0
# https://docs.python.org/2/library/os.html#os.fsync
#os.fsync( fd ) # causes 'Invalid argument' error for some reason...
except OSError as e:
print "OSError in syscall_write: errno=%d" % e.errno
nbytes_written = -1
errno = e.errno
s.rf[v0] = trim_32(nbytes_written)
def syscall_lseek(s):
fd = s.rf[a0]
pos = s.rf[a1]
how = s.rf[a2]
if s.debug.enabled("syscalls"):
print "syscall_lseek( fd=%x, pos=%x, how=%x )" % (fd, pos, how),
if check_fd(s, fd):
return
errno = 0
try:
# NOTE: rpython gives some weird errors in rtyping stage if we don't
# explicitly cast the return value of os.lseek to int
new_pos = int(os.lseek(fd, pos, how))
except OSError as e:
if s.debug.enabled("syscalls"):
print "OSError in syscall_lseek. errno=%d" % e.errno
errno = e.errno
new_pos = -1
return_from_syscall(s, trim_32(new_pos), errno)
def execute_bic(s, inst):
if condition_passed(s, inst.cond()):
a, (b, cout) = s.rf[inst.rn()], shifter_operand(s, inst)
result = a & trim_32(~b)
s.rf[inst.rd()] = trim_32(result)
if inst.S():
if inst.rd() == 15:
raise FatalError('Writing SPSR not implemented!')
s.N = (result >> 31) & 1
s.Z = trim_32(result) == 0
s.C = cout
if inst.rd() == 15:
return
s.rf[PC] = s.fetch_pc() + 4
def syscall_brk(s):
new_brk = s.rf[a0]
if new_brk != 0:
s.breakpoint = new_brk
s.rf[v0] = trim_32(s.breakpoint)
def execute_mvn(s, inst):
if condition_passed(s, inst.cond()):
a, cout = shifter_operand(s, inst)
result = trim_32(~a)
s.rf[inst.rd()] = result
if inst.S():
if inst.rd() == 15:
raise FatalError('Writing SPSR not implemented!')
s.N = (result >> 31) & 1
s.Z = trim_32(result) == 0
s.C = cout
s.V = s.V
if inst.rd() == 15:
return
s.rf[PC] = s.fetch_pc() + 4
def execute_sbc(s, inst):
if condition_passed(s, inst.cond()):
a, (b, _) = s.rf[inst.rn()], shifter_operand(s, inst)
result = a - b - (not s.C)
s.rf[inst.rd()] = trim_32(result)
if inst.S():
if inst.rd() == 15:
raise FatalError('Writing SPSR not implemented!')
s.N = (result >> 31) & 1
s.Z = trim_32(result) == 0
s.C = not borrow_from(result)
s.V = overflow_from_sub(a, b, result)
if inst.rd() == 15:
return
s.rf[PC] = s.fetch_pc() + 4
def execute_mov(s, inst):
if condition_passed(s, inst.cond()):
if inst.rd() == 15 and inst.S():
# if not CurrentModeHasSPSR(): CPSR = SPSR
# else: UNPREDICTABLE
raise FatalError('UNPREDICTABLE in user and system mode!')
result, cout = shifter_operand(s, inst)
s.rf[inst.rd()] = trim_32(result)
if inst.S():
s.N = (result >> 31) & 1
s.Z = trim_32(result) == 0
s.C = cout
s.V = s.V
if inst.rd() == 15:
return
s.rf[PC] = s.fetch_pc() + 4
def execute_blx2(s, inst):
if condition_passed(s, inst.cond()):
s.rf[LR] = trim_32(s.fetch_pc() + 4)
s.T = s.rf[inst.rm()] & 0x00000001
s.rf[PC] = s.rf[inst.rm()] & 0xFFFFFFFE
if s.T:
raise FatalError("Entering THUMB mode! Unsupported!")
# no pc + 4 on success
else:
s.rf[PC] = s.fetch_pc() + 4
def execute_umull(s, inst):
if condition_passed(s, inst.cond()):
if inst.rd() == 15: raise FatalError('UNPREDICTABLE')
if inst.rm() == 15: raise FatalError('UNPREDICTABLE')
if inst.rs() == 15: raise FatalError('UNPREDICTABLE')
if inst.rn() == 15: raise FatalError('UNPREDICTABLE')
RdHi, RdLo = inst.rn(), inst.rd()
Rm, Rs = s.rf[inst.rm()], s.rf[inst.rs()]
result = Rm * Rs
if RdHi == RdLo: raise FatalError('UNPREDICTABLE')
s.rf[RdHi] = trim_32(result >> 32)
s.rf[RdLo] = trim_32(result)
if inst.S():
s.N = (result >> 63) & 1
s.Z = (s.rf[RdHi] == s.rf[RdLo] == 0)
s.rf[PC] = s.fetch_pc() + 4
def execute_tst(s, inst):
if condition_passed(s, inst.cond()):
a, (b, cout) = s.rf[inst.rn()], shifter_operand(s, inst)
result = trim_32(a & b)
if inst.S():
s.N = (result >> 31) & 1
s.Z = result == 0
s.C = cout
if inst.rd() == 15:
return
s.rf[PC] = s.fetch_pc() + 4
def execute_cmp(s, inst):
if condition_passed(s, inst.cond()):
a, (b, _) = s.rf[inst.rn()], shifter_operand(s, inst)
result = a - b
s.N = (result >> 31) & 1
s.Z = trim_32(result) == 0
s.C = not borrow_from(result)
s.V = overflow_from_sub(a, b, result)
if inst.rd() == 15:
return
s.rf[PC] = s.fetch_pc() + 4
def execute_mul(s, inst):
if condition_passed(s, inst.cond()):
Rm, Rs = s.rf[inst.rm()], s.rf[inst.rs()]
result = trim_32(Rm * Rs)
s.rf[inst.rn()] = result
if inst.S():
if inst.rn() == 15: raise FatalError('UNPREDICTABLE')
if inst.rm() == 15: raise FatalError('UNPREDICTABLE')
if inst.rs() == 15: raise FatalError('UNPREDICTABLE')
s.N = (result >> 31) & 1
s.Z = result == 0
if inst.rd() == 15:
return
s.rf[PC] = s.fetch_pc() + 4
def syscall_unlink(s):
path_ptr = s.rf[a0]
#if s.debug.enabled( "syscalls" ):
# print "syscall_unlink( path=%x )" % path_ptr,
path = get_str(s, path_ptr)
errno = 0
try:
os.unlink(path)
except OSError as e:
if s.debug.enabled("syscalls"):
print "OSError in syscall_unlink. errno=%d" % e.errno
errno = e.errno
s.rf[v0] = 0 if errno == 0 else trim_32(-1)
def syscall_close(s):
file_ptr = s.rf[a0]
if file_ptr not in file_descriptors:
s.rf[v0] = -1 # TODO: return a bad file descriptor error (9)?
return
# TODO: hacky don't close the file for 0, 1, 2.
# gem5 does this, but is there a better way?
if file_ptr <= 2:
s.rf[v0] = 0
return
try:
os.close(file_descriptors[file_ptr])
del file_descriptors[file_ptr]
errno = 0
except OSError as e:
print "OSError in syscall_close: errno=%d" % e.errno
errno = e.errno
s.rf[v0] = 0 if errno == 0 else trim_32(-1)
def syscall_link(s):
src_ptr = s.rf[a0]
link_ptr = s.rf[a1]
#if s.debug.enabled( "syscalls" ):
# print "syscall_link( src=%x, link=%x )" % \
# ( src_ptr, link_ptr ),
src = get_str(s, src_ptr)
link_name = get_str(s, link_ptr)
errno = 0
try:
os.link(src, link_name)
except OSError as e:
if s.debug.enabled("syscalls"):
print "OSError in syscall_link. errno=%d" % e.errno
errno = e.errno
s.rf[v0] = 0 if errno == 0 else trim_32(-1)
def syscall_read(s):
file_ptr = s.rf[a0]
data_ptr = s.rf[a1]
nbytes = s.rf[a2]
if file_ptr not in file_descriptors:
s.rf[v0] = -1 # TODO: return a bad file descriptor error (9)?
return
fd = file_descriptors[file_ptr]
try:
data = os.read(fd, nbytes)
nbytes_read = len(data)
errno = 0
put_str(s, data_ptr, data)
except OSError as e:
print "OSError in syscall_read: errno=%d" % e.errno
nbytes_read = -1
errno = e.errno
s.rf[v0] = trim_32(nbytes_read)
def syscall_ioctl(s):
fd = s.rf[a0]
req = s.rf[a1]
result = -errno.ENOTTY if fd >= 0 else -errno.EBADF
s.rf[v0] = trim_32(result)
def return_from_syscall(s, retval, errno):
s.rf[v0] = trim_32(retval)
