diff options
Diffstat (limited to 'miasm2/analysis/data_flow.py')
| -rw-r--r-- | miasm2/analysis/data_flow.py | 62 |
1 files changed, 31 insertions, 31 deletions
diff --git a/miasm2/analysis/data_flow.py b/miasm2/analysis/data_flow.py index d9f61c56..9e5203a6 100644 --- a/miasm2/analysis/data_flow.py +++ b/miasm2/analysis/data_flow.py @@ -29,16 +29,16 @@ class ReachingDefinitions(dict): { (block, index): { lvalue: set((block, index)) } } """ - ir_a = None + ircfg = None - def __init__(self, ir_a): + def __init__(self, ircfg): super(ReachingDefinitions, self).__init__() - self.ir_a = ir_a + self.ircfg = ircfg self.compute() def get_definitions(self, block_lbl, assignblk_index): """Returns the dict { lvalue: set((def_block_lbl, def_index)) } - associated with self.ir_a.@block.assignblks[@assignblk_index] + associated with self.ircfg.@block.assignblks[@assignblk_index] or {} if it is not yet computed """ return self.get((block_lbl, assignblk_index), {}) @@ -48,7 +48,7 @@ class ReachingDefinitions(dict): modified = True while modified: modified = False - for block in self.ir_a.blocks.itervalues(): + for block in self.ircfg.blocks.itervalues(): modified |= self.process_block(block) def process_block(self, block): @@ -57,15 +57,15 @@ class ReachingDefinitions(dict): the assignblk in block @block. """ predecessor_state = {} - for pred_lbl in self.ir_a.graph.predecessors(block.label): - pred = self.ir_a.blocks[pred_lbl] + for pred_lbl in self.ircfg.predecessors(block.loc_key): + pred = self.ircfg.blocks[pred_lbl] for lval, definitions in self.get_definitions(pred_lbl, len(pred)).iteritems(): predecessor_state.setdefault(lval, set()).update(definitions) - modified = self.get((block.label, 0)) != predecessor_state + modified = self.get((block.loc_key, 0)) != predecessor_state if not modified: return False - self[(block.label, 0)] = predecessor_state + self[(block.loc_key, 0)] = predecessor_state for index in xrange(len(block)): modified |= self.process_assignblock(block, index) @@ -80,13 +80,13 @@ class ReachingDefinitions(dict): """ assignblk = block[assignblk_index] - defs = self.get_definitions(block.label, assignblk_index).copy() + defs = self.get_definitions(block.loc_key, assignblk_index).copy() for lval in assignblk: - defs.update({lval: set([(block.label, assignblk_index)])}) + defs.update({lval: set([(block.loc_key, assignblk_index)])}) - modified = self.get((block.label, assignblk_index + 1)) != defs + modified = self.get((block.loc_key, assignblk_index + 1)) != defs if modified: - self[(block.label, assignblk_index + 1)] = defs + self[(block.loc_key, assignblk_index + 1)] = defs return modified @@ -126,7 +126,7 @@ class DiGraphDefUse(DiGraph): # For dot display self._filter_node = None self._dot_offset = None - self._blocks = reaching_defs.ir_a.blocks + self._blocks = reaching_defs.ircfg.blocks super(DiGraphDefUse, self).__init__(*args, **kwargs) self._compute_def_use(reaching_defs, @@ -149,9 +149,9 @@ class DiGraphDefUse(DiGraph): def _compute_def_use_block(self, block, reaching_defs, deref_mem=False): for index, assignblk in enumerate(block): - assignblk_reaching_defs = reaching_defs.get_definitions(block.label, index) + assignblk_reaching_defs = reaching_defs.get_definitions(block.loc_key, index) for lval, expr in assignblk.iteritems(): - self.add_node(AssignblkNode(block.label, index, lval)) + self.add_node(AssignblkNode(block.loc_key, index, lval)) read_vars = expr.get_r(mem_read=deref_mem) if deref_mem and lval.is_mem(): @@ -159,7 +159,7 @@ class DiGraphDefUse(DiGraph): for read_var in read_vars: for reach in assignblk_reaching_defs.get(read_var, set()): self.add_data_edge(AssignblkNode(reach[0], reach[1], read_var), - AssignblkNode(block.label, index, lval)) + AssignblkNode(block.loc_key, index, lval)) def del_edge(self, src, dst): super(DiGraphDefUse, self).del_edge(src, dst) @@ -189,7 +189,7 @@ class DiGraphDefUse(DiGraph): yield self.DotCellDescription(text="", attr={}) -def dead_simp_useful_assignblks(defuse, reaching_defs): +def dead_simp_useful_assignblks(irarch, defuse, reaching_defs): """Mark useful statements using previous reach analysis and defuse Source : Kennedy, K. (1979). A survey of data flow analysis techniques. @@ -200,13 +200,13 @@ def dead_simp_useful_assignblks(defuse, reaching_defs): PRE: compute_reach(self) """ - ir_a = reaching_defs.ir_a + ircfg = reaching_defs.ircfg useful = set() - for block_lbl, block in ir_a.blocks.iteritems(): - successors = ir_a.graph.successors(block_lbl) + for block_lbl, block in ircfg.blocks.iteritems(): + successors = ircfg.successors(block_lbl) for successor in successors: - if successor not in ir_a.blocks: + if successor not in ircfg.blocks: keep_all_definitions = True break else: @@ -217,7 +217,7 @@ def dead_simp_useful_assignblks(defuse, reaching_defs): valid_definitions = reaching_defs.get_definitions(block_lbl, len(block)) for lval, definitions in valid_definitions.iteritems(): - if (lval in ir_a.get_out_regs(block) + if (lval in irarch.get_out_regs(block) or keep_all_definitions): for definition in definitions: useful.add(AssignblkNode(definition[0], definition[1], lval)) @@ -226,7 +226,7 @@ def dead_simp_useful_assignblks(defuse, reaching_defs): for index, assignblk in enumerate(block): for lval, rval in assignblk.iteritems(): if (lval.is_mem() - or ir_a.IRDst == lval + or irarch.IRDst == lval or rval.is_function_call()): useful.add(AssignblkNode(block_lbl, index, lval)) @@ -235,7 +235,7 @@ def dead_simp_useful_assignblks(defuse, reaching_defs): for parent in defuse.reachable_parents(node): yield parent -def dead_simp(ir_a): +def dead_simp(irarch, ircfg): """ Remove useless affectations. @@ -245,21 +245,21 @@ def dead_simp(ir_a): Source : Kennedy, K. (1979). A survey of data flow analysis techniques. IBM Thomas J. Watson Research Division, page 43 - @ir_a: IntermediateRepresentation instance + @ircfg: IntermediateRepresentation instance """ modified = False - reaching_defs = ReachingDefinitions(ir_a) + reaching_defs = ReachingDefinitions(ircfg) defuse = DiGraphDefUse(reaching_defs, deref_mem=True) - useful = set(dead_simp_useful_assignblks(defuse, reaching_defs)) - for block in ir_a.blocks.itervalues(): + useful = set(dead_simp_useful_assignblks(irarch, defuse, reaching_defs)) + for block in ircfg.blocks.itervalues(): irs = [] for idx, assignblk in enumerate(block): new_assignblk = dict(assignblk) for lval in assignblk: - if AssignblkNode(block.label, idx, lval) not in useful: + if AssignblkNode(block.loc_key, idx, lval) not in useful: del new_assignblk[lval] modified = True irs.append(AssignBlock(new_assignblk, assignblk.instr)) - ir_a.blocks[block.label] = IRBlock(block.label, irs) + ircfg.blocks[block.loc_key] = IRBlock(block.loc_key, irs) return modified |