def expr_simp_equal(expr_simp, e):
"""(x - y)?(0:1) == (x == y)"""
to_match = m2_expr.ExprCond(jok1 + jok2, m2_expr.ExprInt1(0),
m2_expr.ExprInt1(1))
r = __MatchExprWrap(e, to_match, [jok1, jok2])
if r is False:
return e
return ExprOp_equal(r[jok1], expr_simp(-r[jok2]))
def bgtz(ir, instr, a, b):
"""Branches on @b if the register @a is greater than zero"""
e = []
n = m2_expr.ExprId(ir.get_next_break_label(instr))
cond = m2_expr.ExprCond(a, m2_expr.ExprInt1(1),
m2_expr.ExprInt1(0)) | a.msb()
dst_o = m2_expr.ExprCond(cond, n, b)
e = [m2_expr.ExprAff(PC, dst_o),
m2_expr.ExprAff(ir.IRDst, dst_o)
]
return e, []
def exec_equal(expr_simp, e):
"Compute x == y"
if e.op != m2_expr.TOK_EQUAL:
return e
arg1, arg2 = e.args
if isinstance(arg1, m2_expr.ExprInt) and isinstance(arg2, m2_expr.ExprInt):
return m2_expr.ExprInt1(1) if (arg1.arg
== arg2.arg) else m2_expr.ExprInt1(0)
else:
return e
def exec_inf_unsigned(expr_simp, e):
"Compute x <u y"
if e.op != m2_expr.TOK_INF_UNSIGNED:
return e
arg1, arg2 = e.args
if isinstance(arg1, m2_expr.ExprInt) and isinstance(arg2, m2_expr.ExprInt):
return m2_expr.ExprInt1(1) if (
arg1.arg < arg2.arg) else m2_expr.ExprInt1(0)
else:
return e
def __comp_signed(arg1, arg2):
"""Return ExprInt1(1) if arg1 <s arg2 else ExprInt1(0)
@arg1, @arg2: ExprInt"""
val1 = arg1.arg
if val1 >> (arg1.size - 1) == 1:
val1 = -(arg1.mask.arg ^ val1 + 1)
val2 = arg2.arg
if val2 >> (arg2.size - 1) == 1:
val2 = -(arg2.mask.arg ^ val2 + 1)
return m2_expr.ExprInt1(1) if (val1 < val2) else m2_expr.ExprInt1(0)
def __comp_signed(arg1, arg2):
"""Return ExprInt1(1) if arg1 <s arg2 else ExprInt1(0)
@arg1, @arg2: ExprInt"""
val1 = int(arg1)
if val1 >> (arg1.size - 1) == 1:
val1 = -((int(arg1.mask) ^ val1) + 1)
val2 = int(arg2)
if val2 >> (arg2.size - 1) == 1:
val2 = -((int(arg2.mask) ^ val2) + 1)
return m2_expr.ExprInt1(1) if (val1 < val2) else m2_expr.ExprInt1(0)
def update_flag_sub_cf(op1, op2, res):
"Compote CF in @res = @op1 - @op2"
return m2_expr.ExprAff(cf, ((((op1 ^ op2) ^ res) ^ ((op1 ^ res) &
(op1 ^ op2))).msb())
^ m2_expr.ExprInt1(1))
def update_flag_zf(a):
return [
m2_expr.ExprAff(
zf, m2_expr.ExprCond(a, m2_expr.ExprInt1(0), m2_expr.ExprInt1(1)))
]
return e
# z = x-y (+cf?)
def update_flag_sub(x, y, z):
e = []
e.append(update_flag_sub_cf(x, y, z))
e.append(update_flag_sub_of(x, y, z))
return e
cond2expr = {
'EQ': zf,
'NE': zf ^ m2_expr.ExprInt1(1),
'CS': cf,
'CC': cf ^ m2_expr.ExprInt1(1),
'MI': nf,
'PL': nf ^ m2_expr.ExprInt1(1),
'VS': of,
'VC': of ^ m2_expr.ExprInt1(1),
'HI': cf & (zf ^ m2_expr.ExprInt1(1)),
'LS': (cf ^ m2_expr.ExprInt1(1)) | zf,
'GE': nf ^ of ^ m2_expr.ExprInt1(1),
'LT': nf ^ of,
'GT': ((zf ^ m2_expr.ExprInt1(1)) & (nf ^ of ^ m2_expr.ExprInt1(1))),
'LE': zf | (nf ^ of),
'AL': m2_expr.ExprInt1(1),
'NV': m2_expr.ExprInt1(0)
}
def to_constraint(self):
cst1, cst2 = m2_expr.ExprInt1(0), m2_expr.ExprInt1(1)
return m2_expr.ExprAff(cst1, m2_expr.ExprCond(self.expr, cst1, cst2))
