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Diffstat (limited to 'miasm/expression/simplifications.py')
| -rw-r--r-- | miasm/expression/simplifications.py | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/miasm/expression/simplifications.py b/miasm/expression/simplifications.py deleted file mode 100644 index 88e59983..00000000 --- a/miasm/expression/simplifications.py +++ /dev/null @@ -1,201 +0,0 @@ -# # -# Simplification methods library # -# # - -import logging - -from future.utils import viewitems - -from miasm.expression import simplifications_common -from miasm.expression import simplifications_cond -from miasm.expression import simplifications_explicit -from miasm.expression.expression_helper import fast_unify -import miasm.expression.expression as m2_expr -from miasm.expression.expression import ExprVisitorCallbackBottomToTop - -# Expression Simplifier -# --------------------- - -log_exprsimp = logging.getLogger("exprsimp") -console_handler = logging.StreamHandler() -console_handler.setFormatter(logging.Formatter("[%(levelname)-8s]: %(message)s")) -log_exprsimp.addHandler(console_handler) -log_exprsimp.setLevel(logging.WARNING) - - -class ExpressionSimplifier(ExprVisitorCallbackBottomToTop): - - """Wrapper on expression simplification passes. - - Instance handle passes lists. - - Available passes lists are: - - commons: common passes such as constant folding - - heavy : rare passes (for instance, in case of obfuscation) - """ - - # Common passes - PASS_COMMONS = { - m2_expr.ExprOp: [ - simplifications_common.simp_cst_propagation, - simplifications_common.simp_cond_op_int, - simplifications_common.simp_cond_factor, - simplifications_common.simp_add_multiple, - # CC op - simplifications_common.simp_cc_conds, - simplifications_common.simp_subwc_cf, - simplifications_common.simp_subwc_of, - simplifications_common.simp_sign_subwc_cf, - simplifications_common.simp_double_zeroext, - simplifications_common.simp_double_signext, - simplifications_common.simp_zeroext_eq_cst, - simplifications_common.simp_ext_eq_ext, - simplifications_common.simp_ext_cond_int, - simplifications_common.simp_sub_cf_zero, - - simplifications_common.simp_cmp_int, - simplifications_common.simp_cmp_bijective_op, - simplifications_common.simp_sign_inf_zeroext, - simplifications_common.simp_cmp_int_int, - simplifications_common.simp_ext_cst, - simplifications_common.simp_zeroext_and_cst_eq_cst, - simplifications_common.simp_test_signext_inf, - simplifications_common.simp_test_zeroext_inf, - simplifications_common.simp_cond_inf_eq_unsigned_zero, - simplifications_common.simp_compose_and_mask, - simplifications_common.simp_bcdadd_cf, - simplifications_common.simp_bcdadd, - simplifications_common.simp_smod_sext, - simplifications_common.simp_flag_cst, - ], - - m2_expr.ExprSlice: [ - simplifications_common.simp_slice, - simplifications_common.simp_slice_of_ext, - simplifications_common.simp_slice_of_sext, - simplifications_common.simp_slice_of_op_ext, - ], - m2_expr.ExprCompose: [simplifications_common.simp_compose], - m2_expr.ExprCond: [ - simplifications_common.simp_cond, - simplifications_common.simp_cond_zeroext, - simplifications_common.simp_cond_add, - # CC op - simplifications_common.simp_cond_flag, - simplifications_common.simp_cmp_int_arg, - - simplifications_common.simp_cond_eq_zero, - simplifications_common.simp_x_and_cst_eq_cst, - simplifications_common.simp_cond_logic_ext, - simplifications_common.simp_cond_sign_bit, - simplifications_common.simp_cond_eq_1_0, - simplifications_common.simp_cond_cc_flag, - simplifications_common.simp_cond_sub_cf, - ], - m2_expr.ExprMem: [simplifications_common.simp_mem], - - } - - - # Heavy passes - PASS_HEAVY = {} - - # Cond passes - PASS_COND = { - m2_expr.ExprSlice: [ - simplifications_cond.expr_simp_inf_signed, - simplifications_cond.expr_simp_inf_unsigned_inversed - ], - m2_expr.ExprOp: [ - simplifications_cond.expr_simp_inverse, - ], - m2_expr.ExprCond: [ - simplifications_cond.expr_simp_equal - ] - } - - - # Available passes lists are: - # - highlevel: transform high level operators to explicit computations - PASS_HIGH_TO_EXPLICIT = { - m2_expr.ExprOp: [ - simplifications_explicit.simp_flags, - simplifications_explicit.simp_ext, - ], - } - - - def __init__(self): - super(ExpressionSimplifier, self).__init__(self.expr_simp_inner) - self.expr_simp_cb = {} - - def enable_passes(self, passes): - """Add passes from @passes - @passes: dict(Expr class : list(callback)) - - Callback signature: Expr callback(ExpressionSimplifier, Expr) - """ - - # Clear cache of simplifiied expressions when adding a new pass - self.cache.clear() - - for k, v in viewitems(passes): - self.expr_simp_cb[k] = fast_unify(self.expr_simp_cb.get(k, []) + v) - - def apply_simp(self, expression): - """Apply enabled simplifications on expression - @expression: Expr instance - Return an Expr instance""" - - cls = expression.__class__ - debug_level = log_exprsimp.level >= logging.DEBUG - for simp_func in self.expr_simp_cb.get(cls, []): - # Apply simplifications - before = expression - expression = simp_func(self, expression) - after = expression - - if debug_level and before != after: - log_exprsimp.debug("[%s] %s => %s", simp_func, before, after) - - # If class changes, stop to prevent wrong simplifications - if expression.__class__ is not cls: - break - - return expression - - def expr_simp_inner(self, expression): - """Apply enabled simplifications on expression and find a stable state - @expression: Expr instance - Return an Expr instance""" - - # Find a stable state - while True: - # Canonize and simplify - new_expr = self.apply_simp(expression.canonize()) - if new_expr == expression: - return new_expr - # Run recursively simplification on fresh new expression - new_expr = self.visit(new_expr) - expression = new_expr - return new_expr - - def expr_simp(self, expression): - "Call simplification recursively" - return self.visit(expression) - - def __call__(self, expression): - "Call simplification recursively" - return self.visit(expression) - - -# Public ExprSimplificationPass instance with commons passes -expr_simp = ExpressionSimplifier() -expr_simp.enable_passes(ExpressionSimplifier.PASS_COMMONS) - -expr_simp_high_to_explicit = ExpressionSimplifier() -expr_simp_high_to_explicit.enable_passes(ExpressionSimplifier.PASS_HIGH_TO_EXPLICIT) - -expr_simp_explicit = ExpressionSimplifier() -expr_simp_explicit.enable_passes(ExpressionSimplifier.PASS_COMMONS) -expr_simp_explicit.enable_passes(ExpressionSimplifier.PASS_HIGH_TO_EXPLICIT) |