def make_F3(cond, c, invert=False, v=False):
# v = True -> PC to be stored in register R15
assert 0 <= cond < 0x111, repr(cond)
assert 0 <= c < 0x10, repr(c)
assert bool(invert) == invert, repr(invert)
assert bool(v) == v, repr(v)
return bint(
(0b11 << 30) + # set p, q
(v << 28) +
(invert << 27) +
(cond << 24) +
c
)
def make_F0(u, op, a, b, c):
assert bool(u) == u, repr(u)
assert ops['Mov'] <= op <= ops['Div'], repr(op)
assert 0 <= a < 0x10, repr(a)
assert 0 <= b < 0x10, repr(b)
assert 0 <= c < 0x10, repr(c)
return bint(
(u << 29) +
(a << 24) +
(b << 20) +
(op << 16) +
c
)
def make_F2(u, v, a, b, offset):
assert bool(u) == u, repr(u)
assert bool(v) == v, repr(v)
assert 0 <= a < 0x10, repr(a)
assert 0 <= b < 0x10, repr(b)
assert 0 <= abs(offset) < 2**20, repr(offset)
return bint(
(1 << 31) +
(u << 29) +
(v << 28) +
(a << 24) +
(b << 20) +
signed(offset, 20)
)
def make_F1(u, v, op, a, b, K):
assert bool(u) == u, repr(u)
assert bool(v) == v, repr(v)
assert ops['Mov'] <= op <= ops['Div'], repr(op)
assert 0 <= a < 0x10, repr(a)
assert 0 <= b < 0x10, repr(b)
assert 0 <= abs(K) < 2**16, repr(K)
return bint(
(1 << 30) + # set q
(u << 29) +
(v << 28) +
(a << 24) +
(b << 20) +
(op << 16) +
signed(K)
)
def dis(n):
'''
Take an integer and return a human-readable string description of the
assembly instruction.
'''
IR = bint(n)[32:0]
p, q = IR[31], IR[30]
if not p:
if not q:
return dis_F0(IR)
return dis_F1(IR)
if not q:
return dis_F2(IR)
if not IR[29]:
return dis_F3(IR)
return dis_F3imm(IR)