cprinter.py

   1 import sys
   2
   3 from utils import pairwise, natural_sort_key
   4 from cfgutils import swap_if_branches
   5 import progdb
   6
   7 no_dead = False
   8
   9 def find_used_labels(cfg):
  10     labels = set()
  11     for addr, nxt in pairwise(cfg.iter_rev_postorder()):
  12         info = cfg[addr]
  13         bblock = info["val"]
  14         succs = cfg.sorted_succ(addr)
  15         if len(succs) > 1 and nxt == succs[0]:
  16             swap_if_branches(cfg, addr)
  17             succs = cfg.sorted_succ(addr)
  18         for succ in succs:
  19             cond = cfg.edge(addr, succ).get("cond")
  20             if not cond and nxt and succ == nxt:
  21                 continue
  22             labels.add(succ)
  23     return labels
  24
  25
  26 def print_inst(inst):
  27     if inst.op == "DEAD" and no_dead:
  28         return
  29     return str(inst)
  30
  31 def dump_c(cfg, stream=sys.stdout):
  32     labels = find_used_labels(cfg)
  33     func_start = True
  34     for addr, nxt in pairwise(cfg.iter_rev_postorder()):
  35         info = cfg[addr]
  36         bblock = info["val"]
  37         if func_start:
  38             label = cfg.props["name"]
  39             if not label:
  40                 label = cfg.parser.label_from_addr(bblock.addr)
  41             if label[0].isdigit():
  42                 label = "fun_" + label
  43             if ("estimated_params" in cfg.props):
  44                 print("// Estimated params: %s" % sorted(list(cfg.props["estimated_params"])), file=stream)
  45             if cfg.props["trailing_jumps"]:
  46                 print("// Trailing jumps not removed, not rendering CFG edges as jumps", file=stream)
  47
  48             func_props = progdb.FUNC_DB.get(label, {})
  49             params = ""
  50             if "params" in func_props:
  51                 params = sorted(func_props["params"], key=natural_sort_key)
  52                 params = ", ".join(["u32 " + str(r) + "_0" for r in params])
  53             print("void %s(%s)\n{" % (label, params), file=stream)
  54             func_start = False
  55         if addr in labels:
  56             print("\nl%s:" % addr, file=stream)
  57         bblock.dump(stream, indent=1, printer=print_inst)
  58         if not cfg.props["trailing_jumps"]:
  59           for succ in cfg.succ(addr):
  60             cond = cfg.edge(addr, succ).get("cond")
  61             if not cond and nxt and succ == nxt:
  62                 continue
  63             stream.write("  ")
  64             if cond:
  65                 stream.write("if %s " % cond)
  66             print("goto l%s;" % succ, file=stream)
  67
  68     print("}", file=stream)