diff options
Diffstat (limited to 'miasm2/expression/simplifications_common.py')
| -rw-r--r-- | miasm2/expression/simplifications_common.py | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/miasm2/expression/simplifications_common.py b/miasm2/expression/simplifications_common.py index ccb97cb3..a1301cba 100644 --- a/miasm2/expression/simplifications_common.py +++ b/miasm2/expression/simplifications_common.py @@ -40,13 +40,26 @@ def simp_cst_propagation(e_s, expr): elif op_name == '|': out = int1.arg | int2.arg elif op_name == '>>': - out = int1.arg >> int2.arg + if int(int2) > int1.size: + out = 0 + else: + out = int1.arg >> int2.arg elif op_name == '<<': - out = int1.arg << int2.arg + if int(int2) > int1.size: + out = 0 + else: + out = int1.arg << int2.arg elif op_name == 'a>>': tmp1 = mod_size2int[int1.arg.size](int1.arg) tmp2 = mod_size2uint[int2.arg.size](int2.arg) - out = mod_size2uint[int1.arg.size](tmp1 >> tmp2) + if tmp2 > int1.size: + is_signed = int(int1) & (1 << (int1.size - 1)) + if is_signed: + out = -1 + else: + out = 0 + else: + out = mod_size2uint[int1.arg.size](tmp1 >> tmp2) elif op_name == '>>>': shifter = int2.arg % int2.size out = (int1.arg >> shifter) | (int1.arg << (int2.size - shifter)) @@ -539,7 +552,7 @@ def simp_compose(e_s, expr): nxt = args[i + 1] if arg.is_mem() and nxt.is_mem(): gap = e_s(nxt.arg - arg.arg) - if gap.is_int() and int(gap) == arg.size / 8: + if gap.is_int() and arg.size % 8 == 0 and int(gap) == arg.size / 8: args = args[:i] + [ExprMem(arg.arg, arg.size + nxt.size)] + args[i + 2:] return ExprCompose(*args) |