src/soc/decoder/pseudo/pagereader.py

   1 # Reads OpenPOWER ISA pages from http://libre-riscv.org/openpower/isa
   2 """OpenPOWER ISA page parser
   3
   4 returns an OrderedDict of namedtuple "Ops" containing details of all
   5 instructions listed in markdown files.
   6
   7 format must be strictly as follows (no optional sections) including whitespace:
   8
   9 # Compare Logical
  10
  11 X-Form
  12
  13 * cmpl BF,L,RA,RB
  14
  15     if L = 0 then a <- [0]*32 || (RA)[32:63]
  16                   b <- [0]*32 || (RB)[32:63]
  17              else a <-  (RA)
  18                   b <-  (RB)
  19     if      a <u b then c <- 0b100
  20     else if a >u b then c <- 0b010
  21     else                c <-  0b001
  22     CR[4*BF+32:4*BF+35] <- c || XER[SO]
  23
  24 Special Registers Altered:
  25
  26     CR field BF
  27     Another field
  28
  29 this translates to:
  30
  31     # heading
  32     blank
  33     Some-Form
  34     blank
  35     * instruction registerlist
  36     * instruction registerlist
  37     blank
  38     4-space-indented pseudo-code
  39     4-space-indented pseudo-code
  40     blank
  41     Special Registers Altered:
  42     4-space-indented register description
  43     blank
  44     blank(s) (optional for convenience at end-of-page)
  45 """
  46
  47 from collections import namedtuple, OrderedDict
  48 from copy import copy
  49 import os
  50
  51 opfields = ("desc", "form", "opcode", "regs", "pcode", "sregs", "page")
  52 Ops = namedtuple("Ops", opfields)
  53
  54
  55 def get_isa_dir():
  56     fdir = os.path.abspath(os.path.dirname(__file__))
  57     fdir = os.path.split(fdir)[0]
  58     fdir = os.path.split(fdir)[0]
  59     fdir = os.path.split(fdir)[0]
  60     fdir = os.path.split(fdir)[0]
  61     return os.path.join(fdir, "libreriscv", "openpower", "isa")
  62
  63
  64 class ISA:
  65
  66     def __init__(self):
  67         self.instr = OrderedDict()
  68         self.forms = {}
  69         self.page = {}
  70         for pth in os.listdir(os.path.join(get_isa_dir())):
  71             print(get_isa_dir(), pth)
  72             assert pth.endswith(".mdwn"), "only %s in isa dir" % pth
  73             self.read_file(pth)
  74             continue
  75             # code which helped add in the keyword "Pseudo-code:" automatically
  76             rewrite = self.read_file_for_rewrite(pth)
  77             name = os.path.join("/tmp", pth)
  78             with open(name, "w") as f:
  79                 f.write('\n'.join(rewrite) + '\n')
  80
  81     def read_file_for_rewrite(self, fname):
  82         pagename = fname.split('.')[0]
  83         fname = os.path.join(get_isa_dir(), fname)
  84         with open(fname) as f:
  85             lines = f.readlines()
  86         rewrite = []
  87
  88         l = lines.pop(0).rstrip()  # get first line
  89         rewrite.append(l)
  90         while lines:
  91             print(l)
  92             # expect get heading
  93             assert l.startswith('#'), ("# not found in line %s" % l)
  94
  95             # whitespace expected
  96             l = lines.pop(0).strip()
  97             print(repr(l))
  98             assert len(l) == 0, ("blank line not found %s" % l)
  99             rewrite.append(l)
 100
 101             # Form expected
 102             l = lines.pop(0).strip()
 103             assert l.endswith('-Form'), ("line with -Form expected %s" % l)
 104             rewrite.append(l)
 105
 106             # whitespace expected
 107             l = lines.pop(0).strip()
 108             assert len(l) == 0, ("blank line not found %s" % l)
 109             rewrite.append(l)
 110
 111             # get list of opcodes
 112             while True:
 113                 l = lines.pop(0).strip()
 114                 rewrite.append(l)
 115                 if len(l) == 0:
 116                     break
 117                 assert l.startswith('*'), ("* not found in line %s" % l)
 118
 119             rewrite.append("Pseudo-code:")
 120             rewrite.append("")
 121             # get pseudocode
 122             while True:
 123                 l = lines.pop(0).rstrip()
 124                 rewrite.append(l)
 125                 if len(l) == 0:
 126                     break
 127                 assert l.startswith('    '), ("4spcs not found in line %s" % l)
 128
 129             # "Special Registers Altered" expected
 130             l = lines.pop(0).rstrip()
 131             assert l.startswith("Special"), ("special not found %s" % l)
 132             rewrite.append(l)
 133
 134             # whitespace expected
 135             l = lines.pop(0).strip()
 136             assert len(l) == 0, ("blank line not found %s" % l)
 137             rewrite.append(l)
 138
 139             # get special regs
 140             while lines:
 141                 l = lines.pop(0).rstrip()
 142                 rewrite.append(l)
 143                 if len(l) == 0:
 144                     break
 145                 assert l.startswith('    '), ("4spcs not found in line %s" % l)
 146
 147             # expect and drop whitespace
 148             while lines:
 149                 l = lines.pop(0).rstrip()
 150                 rewrite.append(l)
 151                 if len(l) != 0:
 152                     break
 153
 154         return rewrite
 155
 156     def read_file(self, fname):
 157         pagename = fname.split('.')[0]
 158         fname = os.path.join(get_isa_dir(), fname)
 159         with open(fname) as f:
 160             lines = f.readlines()
 161
 162         # set up dict with current page name
 163         d = {'page': pagename}
 164
 165         # line-by-line lexer/parser, quite straightforward: pops one
 166         # line off the list and checks it.  nothing complicated needed,
 167         # all sections are mandatory so no need for a full LALR parser.
 168
 169         l = lines.pop(0).rstrip()  # get first line
 170         while lines:
 171             print(l)
 172             # expect get heading
 173             assert l.startswith('#'), ("# not found in line %s" % l)
 174             d['desc'] = l[1:].strip()
 175
 176             # whitespace expected
 177             l = lines.pop(0).strip()
 178             print(repr(l))
 179             assert len(l) == 0, ("blank line not found %s" % l)
 180
 181             # Form expected
 182             l = lines.pop(0).strip()
 183             assert l.endswith('-Form'), ("line with -Form expected %s" % l)
 184             d['form'] = l.split('-')[0]
 185
 186             # whitespace expected
 187             l = lines.pop(0).strip()
 188             assert len(l) == 0, ("blank line not found %s" % l)
 189
 190             # get list of opcodes
 191             li = []
 192             while True:
 193                 l = lines.pop(0).strip()
 194                 if len(l) == 0:
 195                     break
 196                 assert l.startswith('*'), ("* not found in line %s" % l)
 197                 l = l[1:].split(' ')  # lose star
 198                 l = filter(lambda x: len(x) != 0, l)  # strip blanks
 199                 li.append(list(l))
 200             opcodes = li
 201
 202             # "Pseudocode" expected
 203             l = lines.pop(0).rstrip()
 204             assert l.startswith("Pseudo-code:"), ("pseudocode found %s" % l)
 205
 206             # whitespace expected
 207             l = lines.pop(0).strip()
 208             print(repr(l))
 209             assert len(l) == 0, ("blank line not found %s" % l)
 210
 211             # get pseudocode
 212             li = []
 213             while True:
 214                 l = lines.pop(0).rstrip()
 215                 if len(l) == 0:
 216                     break
 217                 assert l.startswith('    '), ("4spcs not found in line %s" % l)
 218                 l = l[4:]  # lose 4 spaces
 219                 li.append(l)
 220             d['pcode'] = li
 221
 222             # "Special Registers Altered" expected
 223             l = lines.pop(0).rstrip()
 224             assert l.startswith("Special"), ("special not found %s" % l)
 225
 226             # whitespace expected
 227             l = lines.pop(0).strip()
 228             assert len(l) == 0, ("blank line not found %s" % l)
 229
 230             # get special regs
 231             li = []
 232             while lines:
 233                 l = lines.pop(0).rstrip()
 234                 if len(l) == 0:
 235                     break
 236                 assert l.startswith('    '), ("4spcs not found in line %s" % l)
 237                 l = l[4:]  # lose 4 spaces
 238                 li.append(l)
 239             d['sregs'] = li
 240
 241             # add in opcode
 242             for o in opcodes:
 243                 self.add_op(o, d)
 244
 245             # expect and drop whitespace
 246             while lines:
 247                 l = lines.pop(0).rstrip()
 248                 if len(l) != 0:
 249                     break
 250
 251     def add_op(self, o, d):
 252         opcode, regs = o[0], o[1:]
 253         op = copy(d)
 254         op['regs'] = regs
 255         regs[0] = regs[0].split(",")
 256         op['opcode'] = opcode
 257         self.instr[opcode] = Ops(**op)
 258
 259         # create list of instructions by form
 260         form = op['form']
 261         fl = self.forms.get(form, [])
 262         self.forms[form] = fl + [opcode]
 263
 264         # create list of instructions by page
 265         page = op['page']
 266         pl = self.page.get(page, [])
 267         self.page[page] = pl + [opcode]
 268
 269     def pprint_ops(self):
 270         for k, v in self.instr.items():
 271             print("# %s %s" % (v.opcode, v.desc))
 272             print("Form: %s Regs: %s" % (v.form, v.regs))
 273             print('\n'.join(map(lambda x: "    %s" % x, v.pcode)))
 274             print("Specials")
 275             print('\n'.join(map(lambda x: "    %s" % x, v.sregs)))
 276             print()
 277         for k, v in isa.forms.items():
 278             print(k, v)
 279
 280
 281 if __name__ == '__main__':
 282     isa = ISA()
 283     isa.pprint_ops()