def get_mem_overlapping(self, e, eval_cache=None):
if eval_cache is None:
eval_cache = {}
if not isinstance(e, m2_expr.ExprMem):
raise ValueError('mem overlap bad arg')
ov = []
# suppose max mem size is 64 bytes, compute all reachable addresses
to_test = []
base_ptr = self.expr_simp(e.arg)
for i in xrange(-7, e.size / 8):
ex = self.expr_simp(
self.eval_expr(base_ptr + m2_expr.ExprInt_from(e.arg, i),
eval_cache))
to_test.append((i, ex))
for i, x in to_test:
if not x in self.symbols.symbols_mem:
continue
ex = self.expr_simp(self.eval_expr(e.arg - x, eval_cache))
if not isinstance(ex, m2_expr.ExprInt):
raise ValueError('ex is not ExprInt')
ptr_diff = int32(ex.arg)
if ptr_diff >= self.symbols.symbols_mem[x][1].size / 8:
# print "too long!"
continue
ov.append((i, self.symbols.symbols_mem[x][0]))
return ov
def get_mem_overlapping(self, e, eval_cache=None):
if eval_cache is None:
eval_cache = {}
if not isinstance(e, m2_expr.ExprMem):
raise ValueError('mem overlap bad arg')
ov = []
# suppose max mem size is 64 bytes, compute all reachable addresses
to_test = []
base_ptr = self.expr_simp(e.arg)
for i in xrange(-7, e.size / 8):
ex = self.expr_simp(
self.eval_expr(base_ptr + m2_expr.ExprInt_from(e.arg, i),
eval_cache))
to_test.append((i, ex))
for i, x in to_test:
if not x in self.symbols.symbols_mem:
continue
ex = self.expr_simp(self.eval_expr(e.arg - x, eval_cache))
if not isinstance(ex, m2_expr.ExprInt):
raise ValueError('ex is not ExprInt')
ptr_diff = int32(ex.arg)
if ptr_diff >= self.symbols.symbols_mem[x][1].size / 8:
# print "too long!"
continue
ov.append((i, self.symbols.symbols_mem[x][0]))
return ov
def substract_mems(self, a, b):
ex = b.arg - a.arg
ex = self.expr_simp(self.eval_expr(ex, {}))
if not isinstance(ex, m2_expr.ExprInt):
return None
ptr_diff = int(int32(ex.arg))
out = []
if ptr_diff < 0:
# [a ]
#[b ]XXX
sub_size = b.size + ptr_diff * 8
if sub_size >= a.size:
pass
else:
ex = m2_expr.ExprOp('+', a.arg,
m2_expr.ExprInt_from(a.arg, sub_size / 8))
ex = self.expr_simp(self.eval_expr(ex, {}))
rest_ptr = ex
rest_size = a.size - sub_size
val = self.symbols[a][sub_size:a.size]
out = [(m2_expr.ExprMem(rest_ptr, rest_size), val)]
else:
#[a ]
# XXXX[b ]YY
#[a ]
# XXXX[b ]
out = []
# part X
if ptr_diff > 0:
val = self.symbols[a][0:ptr_diff * 8]
out.append((m2_expr.ExprMem(a.arg, ptr_diff * 8), val))
# part Y
if ptr_diff * 8 + b.size < a.size:
ex = m2_expr.ExprOp('+', b.arg,
m2_expr.ExprInt_from(b.arg, b.size / 8))
ex = self.expr_simp(self.eval_expr(ex, {}))
rest_ptr = ex
rest_size = a.size - (ptr_diff * 8 + b.size)
val = self.symbols[a][ptr_diff * 8 + b.size:a.size]
out.append((m2_expr.ExprMem(ex, val.size), val))
return out
def substract_mems(self, a, b):
ex = b.arg - a.arg
ex = self.expr_simp(self.eval_expr(ex, {}))
if not isinstance(ex, m2_expr.ExprInt):
return None
ptr_diff = int(int32(ex.arg))
out = []
if ptr_diff < 0:
# [a ]
#[b ]XXX
sub_size = b.size + ptr_diff * 8
if sub_size >= a.size:
pass
else:
ex = m2_expr.ExprOp('+', a.arg,
m2_expr.ExprInt_from(a.arg, sub_size / 8))
ex = self.expr_simp(self.eval_expr(ex, {}))
rest_ptr = ex
rest_size = a.size - sub_size
val = self.symbols[a][sub_size:a.size]
out = [(m2_expr.ExprMem(rest_ptr, rest_size), val)]
else:
#[a ]
# XXXX[b ]YY
#[a ]
# XXXX[b ]
out = []
# part X
if ptr_diff > 0:
val = self.symbols[a][0:ptr_diff * 8]
out.append((m2_expr.ExprMem(a.arg, ptr_diff * 8), val))
# part Y
if ptr_diff * 8 + b.size < a.size:
ex = m2_expr.ExprOp('+', b.arg,
m2_expr.ExprInt_from(b.arg, b.size / 8))
ex = self.expr_simp(self.eval_expr(ex, {}))
rest_ptr = ex
rest_size = a.size - (ptr_diff * 8 + b.size)
val = self.symbols[a][ptr_diff * 8 + b.size:a.size]
out.append((m2_expr.ExprMem(ex, val.size), val))
return out
def substract_mems(self, arg1, arg2):
"""
Return the remaining memory areas of @arg1 - @arg2
@arg1, @arg2: ExprMem
"""
ptr_diff = self.expr_simp(arg2.arg - arg1.arg)
ptr_diff = int(int32(ptr_diff.arg))
zone1 = interval([(0, arg1.size/8-1)])
zone2 = interval([(ptr_diff, ptr_diff + arg2.size/8-1)])
zones = zone1 - zone2
out = []
for start, stop in zones:
ptr = arg1.arg + m2_expr.ExprInt(start, arg1.arg.size)
ptr = self.expr_simp(ptr)
value = self.expr_simp(self.symbols[arg1][start*8:(stop+1)*8])
mem = m2_expr.ExprMem(ptr, (stop - start + 1)*8)
assert mem.size == value.size
out.append((mem, value))
return out
