diff options
Diffstat (limited to 'miasm2/arch/arm/sem.py')
| -rw-r--r-- | miasm2/arch/arm/sem.py | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/miasm2/arch/arm/sem.py b/miasm2/arch/arm/sem.py index d4efba84..9e4da3f6 100644 --- a/miasm2/arch/arm/sem.py +++ b/miasm2/arch/arm/sem.py @@ -1222,6 +1222,7 @@ cond_dct = { # COND_NV: "NV", } +cond_dct_inv = dict((name, num) for num, name in cond_dct.iteritems()) tab_cond = {COND_EQ: zf, COND_NE: ExprCond(zf, ExprInt(0, 1), ExprInt(1, 1)), @@ -1512,6 +1513,118 @@ class ir_arml(IntermediateRepresentation): self.mod_pc(instr, instr_ir, extra_ir) return instr_ir, extra_ir + def parse_itt(self, instr): + name = instr.name + assert name.startswith('IT') + name = name[1:] + out = [] + for hint in name: + if hint == 'T': + out.append(0) + elif hint == "E": + out.append(1) + else: + raise ValueError("IT name invalid %s" % instr) + return out, instr.args[0] + + def do_it_block(self, label, index, block, assignments, gen_pc_updt): + instr = block.lines[index] + it_hints, it_cond = self.parse_itt(instr) + cond_num = cond_dct_inv[it_cond.name] + cond_eq = tab_cond[cond_num] + + if not index + len(it_hints) <= len(block.lines): + raise NotImplementedError("Splitted IT block non supported yet") + + ir_blocks_all = [] + + # Gen dummy irblock for IT instr + label_next = self.get_next_label(instr) + dst = ExprAff(self.IRDst, ExprId(label_next, 32)) + dst_blk = AssignBlock([dst], instr) + assignments.append(dst_blk) + irblock = IRBlock(label, assignments) + ir_blocks_all.append([irblock]) + + label = label_next + assignments = [] + for hint in it_hints: + irblocks = [] + index += 1 + instr = block.lines[index] + + # Add conditionnal jump to current irblock + label_do = self.symbol_pool.gen_label() + label_next = self.get_next_label(instr) + + if hint: + local_cond = ~cond_eq + else: + local_cond = cond_eq + dst = ExprAff(self.IRDst, ExprCond(local_cond, ExprId(label_do, 32), ExprId(label_next, 32))) + dst_blk = AssignBlock([dst], instr) + assignments.append(dst_blk) + irblock = IRBlock(label, assignments) + + irblocks.append(irblock) + + assignments = [] + label = label_do + split = self.add_instr_to_irblock(block, instr, assignments, + irblocks, gen_pc_updt) + if split: + raise NotImplementedError("Unsupported instr in IT block (%s)" % instr) + + dst = ExprAff(self.IRDst, ExprId(label_next, 32)) + dst_blk = AssignBlock([dst], instr) + assignments.append(dst_blk) + irblock = IRBlock(label, assignments) + irblocks.append(irblock) + label = label_next + assignments = [] + ir_blocks_all.append(irblocks) + return index, ir_blocks_all + + def add_block(self, block, gen_pc_updt=False): + """ + Add a native block to the current IR + @block: native assembly block + @gen_pc_updt: insert PC update effects between instructions + """ + + it_hints = None + it_cond = None + label = None + ir_blocks_all = [] + index = -1 + while index + 1 < len(block.lines): + index += 1 + instr = block.lines[index] + if label is None: + assignments = [] + label = self.get_instr_label(instr) + if instr.name.startswith("IT"): + index, irblocks_it = self.do_it_block(label, index, block, assignments, gen_pc_updt) + for irblocks in irblocks_it: + ir_blocks_all += irblocks + label = None + continue + + split = self.add_instr_to_irblock(block, instr, assignments, + ir_blocks_all, gen_pc_updt) + if split: + ir_blocks_all.append(IRBlock(label, assignments)) + label = None + assignments = [] + if label is not None: + ir_blocks_all.append(IRBlock(label, assignments)) + + new_ir_blocks_all = self.post_add_block(block, ir_blocks_all) + for irblock in new_ir_blocks_all: + self.blocks[irblock.label] = irblock + return new_ir_blocks_all + + class ir_armb(ir_arml): def __init__(self, symbol_pool=None): |