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comparison python/ppci/core/bitreader.py @ 104:ed230e947dc6

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Added hexviewer
author windel
date Sun, 30 Dec 2012 22:31:55 +0100
parents 4a37d6992bd3
children 6a303f835c6d
comparison
equal deleted inserted replaced
103:28a35161ef23 104:ed230e947dc6
24 b = self.stream.read(1) 24 b = self.stream.read(1)
25 print(b) 25 print(b)
26 return int(b[0]) 26 return int(b[0])
27 return 2 27 return 2
28 28
29 class BitstreamWriter:
30 def __init__(self, f):
31 self.f = f
32 self.u32 = 0
33 self.curpos = 0
34 def Emit1(self, val):
35 self.Emit(val, 1)
36 def Emit(self, val, numbits):
37 """ Emits value using numbits bits """
38 if numbits == 1:
39 if val != 0:
40 self.u32 |= (0x1 << self.curpos)
41 self.curpos += 1
42 if self.curpos == 32:
43 self.writeWord()
44 elif numbits > 1:
45 for i in range(numbits):
46 if val & (1 << i) != 0:
47 self.Emit1(1)
48 else:
49 self.Emit1(0)
50 def writeWord(self):
51 bts = struct.pack('<I', self.u32)
52 self.f.write(bts)
53 self.u32 = 0
54 self.curpos = 0
55 def flush(self):
56 if self.curpos != 0:
57 self.writeWord()
58
59 class BitcodeWriter:
60 def __init__(self):
61 pass
62 def WriteModule(self, module):
63 pass
64 def WriteModuleToFile(self, module, f):
65 s = BitstreamWriter(f)
66 s.Emit(ord('B'), 8)
67 s.Emit(ord('C'), 8)
68 s.Emit(0x0, 4)
69 s.Emit(0xC, 4)
70 s.Emit(0xE, 4)
71 s.Emit(0xD, 4)
72 self.WriteModule(module)
73 s.flush()
74