diff options
| -rw-r--r-- | miasm2/expression/expression.py | 182 | ||||
| -rw-r--r-- | test/expression/expr_cmp.py | 107 | ||||
| -rwxr-xr-x | test/test_all.py | 1 |
3 files changed, 290 insertions, 0 deletions
diff --git a/miasm2/expression/expression.py b/miasm2/expression/expression.py index b7b90470..591dc024 100644 --- a/miasm2/expression/expression.py +++ b/miasm2/expression/expression.py @@ -1538,3 +1538,185 @@ def get_expr_mem(expr): ops = set() expr.visit(lambda x: visit_getmem(x, ops)) return ops + + +def _expr_compute_cf(op1, op2): + """ + Get carry flag of @op1 - @op2 + Ref: x86 cf flag + @op1: Expression + @op2: Expression + """ + res = op1 - op2 + cf = (((op1 ^ op2) ^ res) ^ ((op1 ^ res) & (op1 ^ op2))).msb() + return cf + +def _expr_compute_of(op1, op2): + """ + Get overflow flag of @op1 - @op2 + Ref: x86 of flag + @op1: Expression + @op2: Expression + """ + res = op1 - op2 + of = (((op1 ^ res) & (op1 ^ op2))).msb() + return of + +def _expr_compute_zf(op1, op2): + """ + Get zero flag of @op1 - @op2 + @op1: Expression + @op2: Expression + """ + res = op1 - op2 + zf = ExprCond(res, + ExprInt(0, 1), + ExprInt(1, 1)) + return zf + + +def _expr_compute_nf(op1, op2): + """ + Get negative (or sign) flag of @op1 - @op2 + @op1: Expression + @op2: Expression + """ + res = op1 - op2 + nf = res.msb() + return nf + + +def expr_is_equal(op1, op2): + """ + if op1 == op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + zf = _expr_compute_zf(op1, op2) + return zf + + +def expr_is_not_equal(op1, op2): + """ + if op1 != op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + zf = _expr_compute_zf(op1, op2) + return ~zf + + +def expr_is_unsigned_greater(op1, op2): + """ + UNSIGNED cmp + if op1 > op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + cf = _expr_compute_cf(op1, op2) + zf = _expr_compute_zf(op1, op2) + return ~(cf | zf) + + +def expr_is_unsigned_greater_or_equal(op1, op2): + """ + Unsigned cmp + if op1 >= op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + cf = _expr_compute_cf(op1, op2) + return ~cf + + +def expr_is_unsigned_lower(op1, op2): + """ + Unsigned cmp + if op1 < op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + cf = _expr_compute_cf(op1, op2) + return cf + + +def expr_is_unsigned_lower_or_equal(op1, op2): + """ + Unsigned cmp + if op1 <= op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + cf = _expr_compute_cf(op1, op2) + zf = _expr_compute_zf(op1, op2) + return cf | zf + + +def expr_is_signed_greater(op1, op2): + """ + Signed cmp + if op1 > op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + nf = _expr_compute_nf(op1, op2) + of = _expr_compute_of(op1, op2) + zf = _expr_compute_zf(op1, op2) + return ~(zf | (nf ^ of)) + + +def expr_is_signed_greater_or_equal(op1, op2): + """ + Signed cmp + if op1 > op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + nf = _expr_compute_nf(op1, op2) + of = _expr_compute_of(op1, op2) + return ~(nf ^ of) + + +def expr_is_signed_lower(op1, op2): + """ + Signed cmp + if op1 < op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + nf = _expr_compute_nf(op1, op2) + of = _expr_compute_of(op1, op2) + return nf ^ of + + +def expr_is_signed_lower_or_equal(op1, op2): + """ + Signed cmp + if op1 <= op2: + Return ExprInt(1, 1) + else: + Return ExprInt(0, 1) + """ + + nf = _expr_compute_nf(op1, op2) + of = _expr_compute_of(op1, op2) + zf = _expr_compute_zf(op1, op2) + return zf | (nf ^ of) diff --git a/test/expression/expr_cmp.py b/test/expression/expr_cmp.py new file mode 100644 index 00000000..b238151d --- /dev/null +++ b/test/expression/expr_cmp.py @@ -0,0 +1,107 @@ +# +# Expression comparison regression tests # +# +from pdb import pm +from miasm2.expression.expression import ExprInt, expr_is_unsigned_greater,\ + expr_is_unsigned_greater_or_equal, expr_is_unsigned_lower,\ + expr_is_unsigned_lower_or_equal, expr_is_signed_greater,\ + expr_is_signed_greater_or_equal, expr_is_signed_lower, \ + expr_is_signed_lower_or_equal, expr_is_equal, expr_is_not_equal +from miasm2.expression.simplifications import expr_simp + +int_0 = ExprInt(0, 32) +int_1 = ExprInt(1, 32) +int_m1 = ExprInt(-1, 32) +int_m2 = ExprInt(-2, 32) + +b0 = ExprInt(0, 1) +b1 = ExprInt(1, 1) + +tests = [ + # unsigned + (b1, expr_is_unsigned_greater, int_1, int_0), + (b1, expr_is_unsigned_lower, int_0, int_1), + + (b0, expr_is_unsigned_greater, int_0, int_1), + (b0, expr_is_unsigned_lower, int_1, int_0), + + (b1, expr_is_unsigned_greater_or_equal, int_1, int_0), + (b1, expr_is_unsigned_lower_or_equal, int_0, int_1), + + (b0, expr_is_unsigned_greater_or_equal, int_0, int_1), + (b0, expr_is_unsigned_lower_or_equal, int_1, int_0), + + (b1, expr_is_unsigned_greater_or_equal, int_1, int_1), + (b1, expr_is_unsigned_lower_or_equal, int_1, int_1), + + (b1, expr_is_unsigned_greater, int_m1, int_0), + (b1, expr_is_unsigned_lower, int_0, int_m1), + + (b0, expr_is_unsigned_greater, int_0, int_m1), + (b0, expr_is_unsigned_lower, int_m1, int_0), + + + # signed + (b1, expr_is_signed_greater, int_1, int_0), + (b1, expr_is_signed_lower, int_0, int_1), + + (b0, expr_is_signed_greater, int_0, int_1), + (b0, expr_is_signed_lower, int_1, int_0), + + (b1, expr_is_signed_greater_or_equal, int_1, int_0), + (b1, expr_is_signed_lower_or_equal, int_0, int_1), + + (b0, expr_is_signed_greater_or_equal, int_0, int_1), + (b0, expr_is_signed_lower_or_equal, int_1, int_0), + + (b1, expr_is_signed_greater_or_equal, int_1, int_1), + (b1, expr_is_signed_lower_or_equal, int_1, int_1), + + (b0, expr_is_signed_greater, int_m1, int_0), + (b0, expr_is_signed_lower, int_0, int_m1), + + (b1, expr_is_signed_greater, int_0, int_m1), + (b1, expr_is_signed_lower, int_m1, int_0), + + + # greater lesser, neg + (b1, expr_is_signed_greater, int_1, int_m1), + (b1, expr_is_signed_lower, int_m1, int_1), + + (b0, expr_is_signed_greater, int_m1, int_1), + (b0, expr_is_signed_lower, int_1, int_m1), + + (b1, expr_is_signed_greater_or_equal, int_1, int_m1), + (b1, expr_is_signed_lower_or_equal, int_m1, int_1), + + (b0, expr_is_signed_greater_or_equal, int_m1, int_1), + (b0, expr_is_signed_lower_or_equal, int_1, int_m1), + + (b1, expr_is_signed_greater_or_equal, int_m1, int_m1), + (b1, expr_is_signed_lower_or_equal, int_m1, int_m1), + + + (b1, expr_is_signed_greater, int_m1, int_m2), + (b1, expr_is_signed_lower, int_m2, int_m1), + + (b0, expr_is_signed_greater, int_m2, int_m1), + (b0, expr_is_signed_lower, int_m1, int_m2), + + (b1, expr_is_signed_greater_or_equal, int_m1, int_m2), + (b1, expr_is_signed_lower_or_equal, int_m2, int_m1), + + (b0, expr_is_signed_greater_or_equal, int_m2, int_m1), + (b0, expr_is_signed_lower_or_equal, int_m1, int_m2), + + # eq/neq + (b1, expr_is_equal, int_1, int_1), + (b1, expr_is_not_equal, int_0, int_1), + + (b0, expr_is_equal, int_1, int_0), + (b0, expr_is_not_equal, int_0, int_0), + + +] + +for result, func, arg1, arg2 in tests: + assert result == expr_simp(func(arg1, arg2)) diff --git a/test/test_all.py b/test/test_all.py index 17193d9f..70ad62b8 100755 --- a/test/test_all.py +++ b/test/test_all.py @@ -245,6 +245,7 @@ for script in ["modint.py", "expression_helper.py", "expr_pickle.py", "parser.py", + "expr_cmp.py", ]: testset += RegressionTest([script], base_dir="expression") |