src/openpower/decoder/power_fields.py

   1 from collections import OrderedDict, namedtuple
   2 from openpower.decoder.power_enums import find_wiki_file
   3
   4
   5 class BitRange(OrderedDict):
   6     """BitRange: remaps from straight indices (0,1,2..) to bit numbers
   7     """
   8
   9     def __getitem__(self, subscript):
  10         if isinstance(subscript, slice):
  11             return list(self.values())[subscript]
  12         else:
  13             return OrderedDict.__getitem__(self, subscript)
  14
  15
  16 def decode_instructions(form):
  17     res = {}
  18     accum = []
  19     for l in form:
  20         if l.strip().startswith("Formats"):
  21             l = l.strip().split(":")[-1]
  22             l = l.replace(" ", "")
  23             l = l.split(",")
  24             for fmt in l:
  25                 if fmt not in res:
  26                     res[fmt] = [accum[0]]
  27                 else:
  28                     res[fmt].append(accum[0])
  29             accum = []
  30         else:
  31             accum.append(l.strip())
  32     return res
  33
  34
  35 def decode_form_header(hdr):
  36     res = {}
  37     count = 0
  38     hdr = hdr.strip()
  39     for f in hdr.split("|"):
  40         if not f:
  41             continue
  42         if f[0].isdigit():
  43             idx = int(f.strip().split(' ')[0])
  44             res[count] = idx
  45         count += len(f) + 1
  46     return res
  47
  48
  49 def find_unique(d, key):
  50     if key not in d:
  51         return key
  52     idx = 1
  53     while "%s_%d" % (key, idx) in d:
  54         idx += 1
  55     return "%s_%d" % (key, idx)
  56
  57
  58 def decode_line(header, line):
  59     line = line.strip()
  60     res = {}
  61     count = 0
  62     prev_fieldname = None
  63     for f in line.split("|"):
  64         if not f:
  65             continue
  66         end = count + len(f) + 1
  67         fieldname = f.strip()
  68         if not fieldname or fieldname.startswith('/'):
  69             if prev_fieldname is not None:
  70                 res[prev_fieldname] = (res[prev_fieldname], header[count])
  71                 prev_fieldname = None
  72             count = end
  73             continue
  74         bitstart = header[count]
  75         if prev_fieldname is not None:
  76             res[prev_fieldname] = (res[prev_fieldname], bitstart)
  77         res[fieldname] = bitstart
  78         count = end
  79         prev_fieldname = fieldname
  80     res[prev_fieldname] = (bitstart, 32)
  81     return res
  82
  83
  84 def decode_form(form):
  85     header = decode_form_header(form[0])
  86     res = []
  87     for line in form[1:]:
  88         dec = decode_line(header, line)
  89         if dec:
  90             res.append(dec)
  91     fields = {}
  92     falternate = {}
  93     for l in res:
  94         for k, (start, end) in l.items():
  95             if k in fields:
  96                 if (start, end) == fields[k]:
  97                     continue  # already in and matching for this Form
  98                 if k in falternate:
  99                     alternate = "%s_%d" % (k, falternate[k])
 100                     if (start, end) == fields[alternate]:
 101                         continue
 102                 falternate[k] = fidx = falternate.get(k, 0) + 1
 103                 fields["%s_%d" % (k, fidx)] = (start, end)
 104             else:
 105                 fields[k] = (start, end)
 106     return fields
 107
 108
 109 class DecodeFields:
 110
 111     def __init__(self, bitkls=BitRange, bitargs=(), fname=None,
 112                  name_on_wiki=None):
 113         self.bitkls = bitkls
 114         self.bitargs = bitargs
 115         if fname is None:
 116             assert name_on_wiki is None
 117             fname = "fields.txt"
 118             name_on_wiki = "fields.text"
 119         self.fname = find_wiki_file(name_on_wiki)
 120
 121     @property
 122     def form_names(self):
 123         return self.instrs.keys()
 124
 125     def create_specs(self):
 126         self.forms, self.instrs = self.decode_fields()
 127         forms = self.form_names
 128         #print ("specs", self.forms, forms)
 129         for form in forms:
 130             fields = self.instrs[form]
 131             fk = fields.keys()
 132             Fields = namedtuple("Fields", fk)
 133             instr = Fields(**fields)
 134             setattr(self, "Form%s" % form, instr)
 135         # now add in some commonly-used fields (should be done automatically)
 136         # note that these should only be ones which are the same on all Forms
 137         # note: these are from microwatt insn_helpers.vhdl
 138         self.common_fields = {
 139             "PO": self.Formall.PO,
 140             "RS": self.FormX.RS,
 141             "RT": self.FormX.RT,
 142             "RA": self.FormX.RA,
 143             "RB": self.FormX.RB,
 144             "SI": self.FormD.SI,
 145             "UI": self.FormD.UI,
 146             "L": self.FormD.L,
 147             "SH32": self.FormM.SH,
 148             "sh": self.FormMD.sh,
 149             "MB32": self.FormM.MB,
 150             "ME32": self.FormM.ME,
 151             "LI": self.FormI.LI,
 152             "LK": self.FormI.LK,
 153             "AA": self.FormB.AA,
 154             "Rc": self.FormX.Rc,
 155             "OE": self.FormXO.OE,
 156             "BD": self.FormB.BD,
 157             "BF": self.FormX.BF,
 158             "CR": self.FormXL.XO,
 159             "BB": self.FormXL.BB,
 160             "BA": self.FormXL.BA,
 161             "BT": self.FormXL.BT,
 162             "FXM": self.FormXFX.FXM,
 163             "BO": self.FormXL.BO,
 164             "BI": self.FormXL.BI,
 165             "BH": self.FormXL.BH,
 166             "D": self.FormD.D,
 167             "DS": self.FormDS.DS,
 168             "TO": self.FormX.TO,
 169             "BC": self.FormA.BC,
 170             "SH": self.FormX.SH,
 171             "ME": self.FormM.ME,
 172             "MB": self.FormM.MB,
 173             "SPR": self.FormXFX.SPR}
 174         for k, v in self.common_fields.items():
 175             setattr(self, k, v)
 176
 177     def decode_fields(self):
 178         with open(self.fname) as f:
 179             txt = f.readlines()
 180         #print ("decode", txt)
 181         forms = {}
 182         reading_data = False
 183         for l in txt:
 184             l = l.strip()
 185             if len(l) == 0:
 186                 continue
 187             if reading_data:
 188                 if l[0] == '#':
 189                     reading_data = False
 190                 else:
 191                     forms[heading].append(l)
 192             if not reading_data:
 193                 assert l[0] == '#'
 194                 heading = l[1:].strip()
 195                 # if heading.startswith('1.6.28'): # skip instr fields for now
 196                 #     break
 197                 heading = heading.split(' ')[-1]
 198                 reading_data = True
 199                 forms[heading] = []
 200
 201         res = {}
 202         inst = {}
 203
 204         for hdr, form in forms.items():
 205             if heading == 'Fields':
 206                 i = decode_instructions(form)
 207                 for form, field in i.items():
 208                     inst[form] = self.decode_instruction_fields(field)
 209             # else:
 210             #     res[hdr] = decode_form(form)
 211         return res, inst
 212
 213     def decode_instruction_fields(self, fields):
 214         res = {}
 215         for field in fields:
 216             f, spec = field.strip().split(" ")
 217             ss = spec[1:-1].split(",")
 218             fs = f.split(",")
 219             if len(fs) > 1:
 220                 individualfields = []
 221                 for f0, s0 in zip(fs, ss):
 222                     txt = "%s (%s)" % (f0, s0)
 223                     individualfields.append(txt)
 224                 if len(fs) > 1:
 225                     res.update(self.decode_instruction_fields(
 226                         individualfields))
 227             d = self.bitkls(*self.bitargs)
 228             idx = 0
 229             for s in ss:
 230                 s = s.split(':')
 231                 if len(s) == 1:
 232                     d[idx] = int(s[0])
 233                     idx += 1
 234                 else:
 235                     start = int(s[0])
 236                     end = int(s[1])
 237                     while start <= end:
 238                         d[idx] = start
 239                         idx += 1
 240                         start += 1
 241             f = f.replace(",", "_")
 242             unique = find_unique(res, f)
 243             res[unique] = d
 244
 245         return res
 246
 247
 248 if __name__ == '__main__':
 249     dec = DecodeFields()
 250     dec.create_specs()
 251     forms, instrs = dec.forms, dec.instrs
 252     for form, fields in instrs.items():
 253         print("Form", form)
 254         for field, bits in fields.items():
 255             print("\tfield", field, bits)