gdb/make-target-delegates.py

   1 #!/usr/bin/env python3
   2
   3 # Copyright (C) 2013-2022 Free Software Foundation, Inc.
   4 #
   5 # This file is part of GDB.
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19
  20 # Usage:
  21 #    make-target-delegates.py
  22
  23 import re
  24 import gdbcopyright
  25
  26
  27 # The line we search for in target.h that marks where we should start
  28 # looking for methods.
  29 TRIGGER = re.compile(r"^struct target_ops$")
  30 # The end of the methods part.
  31 ENDER = re.compile(r"^\s*};$")
  32
  33 # Match a C symbol.
  34 SYMBOL = "[a-zA-Z_][a-zA-Z0-9_]*"
  35 # Match the name part of a method in struct target_ops.
  36 NAME_PART = r"(?P<name>" + SYMBOL + ")\s"
  37 # Match the arguments to a method.
  38 ARGS_PART = r"(?P<args>\(.*\))"
  39 # We strip the indentation so here we only need the caret.
  40 INTRO_PART = r"^"
  41
  42 POINTER_PART = r"\s*(\*)?\s*"
  43
  44 # Match a C++ symbol, including scope operators and template
  45 # parameters.  E.g., 'std::vector<something>'.
  46 CP_SYMBOL = r"[a-zA-Z_][a-zA-Z0-9_<>:]*"
  47 # Match the return type when it is "ordinary".
  48 SIMPLE_RETURN_PART = r"((struct|class|enum|union)\s+)?" + CP_SYMBOL
  49
  50 # Match a return type.
  51 RETURN_PART = r"((const|volatile)\s+)?(" + SIMPLE_RETURN_PART + ")" + POINTER_PART
  52
  53 # Match "virtual".
  54 VIRTUAL_PART = r"virtual\s"
  55
  56 # Match the TARGET_DEFAULT_* attribute for a method.
  57 TARGET_DEFAULT_PART = r"TARGET_DEFAULT_(?P<style>[A-Z_]+)\s*\((?P<default_arg>.*)\)"
  58
  59 # Match the arguments and trailing attribute of a method definition.
  60 # Note we don't match the trailing ";".
  61 METHOD_TRAILER = r"\s*" + TARGET_DEFAULT_PART + "$"
  62
  63 # Match an entire method definition.
  64 METHOD = re.compile(
  65     INTRO_PART
  66     + VIRTUAL_PART
  67     + "(?P<return_type>"
  68     + RETURN_PART
  69     + ")"
  70     + NAME_PART
  71     + ARGS_PART
  72     + METHOD_TRAILER
  73 )
  74
  75 # Regular expression used to dissect argument types.
  76 ARGTYPES = re.compile(
  77     "^("
  78     + r"(?P<E>enum\s+"
  79     + SYMBOL
  80     + r"\s*)("
  81     + SYMBOL
  82     + ")?"
  83     + r"|(?P<T>.*(enum\s+)?"
  84     + SYMBOL
  85     + r".*(\s|\*|&))"
  86     + SYMBOL
  87     + ")$"
  88 )
  89
  90 # Match TARGET_DEBUG_PRINTER in an argument type.
  91 # This must match the whole "sub-expression" including the parens.
  92 TARGET_DEBUG_PRINTER = r"\s*TARGET_DEBUG_PRINTER\s*\((?P<arg>[^)]*)\)\s*"
  93
  94
  95 def scan_target_h():
  96     found_trigger = False
  97     all_the_text = ""
  98     with open("target.h", "r") as target_h:
  99         for line in target_h:
 100             line = line.strip()
 101             if not found_trigger:
 102                 if TRIGGER.match(line):
 103                     found_trigger = True
 104             elif "{" in line:
 105                 # Skip the open brace.
 106                 pass
 107             elif ENDER.match(line):
 108                 break
 109             else:
 110                 # Strip // comments.
 111                 line = re.split("//", line)[0]
 112                 all_the_text = all_the_text + " " + line
 113     if not found_trigger:
 114         raise "Could not find trigger line"
 115     # Now strip out the C comments.
 116     all_the_text = re.sub(r"/\*(.*?)\*/", "", all_the_text)
 117     # Replace sequences whitespace with a single space character.
 118     # We need the space because the method may have been split
 119     # between multiple lines, like e.g.:
 120     #
 121     #  virtual std::vector<long_type_name>
 122     #    my_long_method_name ()
 123     #    TARGET_DEFAULT_IGNORE ();
 124     #
 125     # If we didn't preserve the space, then we'd end up with:
 126     #
 127     #  virtual std::vector<long_type_name>my_long_method_name ()TARGET_DEFAULT_IGNORE ()
 128     #
 129     # ... which wouldn't later be parsed correctly.
 130     all_the_text = re.sub(r"\s+", " ", all_the_text)
 131     return all_the_text.split(";")
 132
 133
 134 # Parse arguments into a list.
 135 def parse_argtypes(typestr):
 136     # Remove the outer parens.
 137     typestr = re.sub(r"^\((.*)\)$", r"\1", typestr)
 138     result = []
 139     for item in re.split(r",\s*", typestr):
 140         if item == "void" or item == "":
 141             continue
 142         m = ARGTYPES.match(item)
 143         if m:
 144             if m.group("E"):
 145                 onetype = m.group("E")
 146             else:
 147                 onetype = m.group("T")
 148         else:
 149             onetype = item
 150         result.append(onetype.strip())
 151     return result
 152
 153
 154 # Write function header given name, return type, and argtypes.
 155 # Returns a list of actual argument names.
 156 def write_function_header(f, decl, name, return_type, argtypes):
 157     print(return_type, file=f, end="")
 158     if decl:
 159         if not return_type.endswith("*"):
 160             print(" ", file=f, end="")
 161     else:
 162         print("", file=f)
 163     print(name + " (", file=f, end="")
 164     argdecls = []
 165     actuals = []
 166     for i in range(len(argtypes)):
 167         val = re.sub(TARGET_DEBUG_PRINTER, "", argtypes[i])
 168         if not val.endswith("*") and not val.endswith("&"):
 169             val = val + " "
 170         vname = "arg" + str(i)
 171         val = val + vname
 172         argdecls.append(val)
 173         actuals.append(vname)
 174     print(", ".join(argdecls) + ")", file=f, end="")
 175     if decl:
 176         print(" override;", file=f)
 177     else:
 178         print("\n{", file=f)
 179     return actuals
 180
 181
 182 # Write out a declaration.
 183 def write_declaration(f, name, return_type, argtypes):
 184     write_function_header(f, True, name, return_type, argtypes)
 185
 186
 187 # Write out a delegation function.
 188 def write_delegator(f, name, return_type, argtypes):
 189     names = write_function_header(
 190         f, False, "target_ops::" + name, return_type, argtypes
 191     )
 192     print("  ", file=f, end="")
 193     if return_type != "void":
 194         print("return ", file=f, end="")
 195     print("this->beneath ()->" + name + " (", file=f, end="")
 196     print(", ".join(names), file=f, end="")
 197     print(");", file=f)
 198     print("}\n", file=f)
 199
 200
 201 # Write out a default function.
 202 def write_tdefault(f, content, style, name, return_type, argtypes):
 203     name = "dummy_target::" + name
 204     names = write_function_header(f, False, name, return_type, argtypes)
 205     if style == "FUNC":
 206         print("  ", file=f, end="")
 207         if return_type != "void":
 208             print("return ", file=f, end="")
 209         print(content + " (", file=f, end="")
 210         names.insert(0, "this")
 211         print(", ".join(names) + ");", file=f)
 212     elif style == "RETURN":
 213         print("  return " + content + ";", file=f)
 214     elif style == "NORETURN":
 215         print("  " + content + ";", file=f)
 216     elif style == "IGNORE":
 217         # Nothing.
 218         pass
 219     else:
 220         raise "unrecognized style: " + style
 221     print("}\n", file=f)
 222
 223
 224 def munge_type(typename):
 225     m = re.search(TARGET_DEBUG_PRINTER, typename)
 226     if m:
 227         return m.group("arg")
 228     typename = typename.rstrip()
 229     typename = re.sub("[ ()<>:]", "_", typename)
 230     typename = re.sub("[*]", "p", typename)
 231     typename = re.sub("&", "r", typename)
 232     # Identifers with double underscores are reserved to the C++
 233     # implementation.
 234     typename = re.sub("_+", "_", typename)
 235     # Avoid ending the function name with underscore, for
 236     # cosmetics.  Trailing underscores appear after munging types
 237     # with template parameters, like e.g. "foo<int>".
 238     typename = re.sub("_+$", "", typename)
 239     return "target_debug_print_" + typename
 240
 241
 242 # Write out a debug method.
 243 def write_debugmethod(f, content, name, return_type, argtypes):
 244     debugname = "debug_target::" + name
 245     names = write_function_header(f, False, debugname, return_type, argtypes)
 246     if return_type != "void":
 247         print("  " + return_type + " result;", file=f)
 248     print(
 249         '  gdb_printf (gdb_stdlog, "-> %s->'
 250         + name
 251         + ' (...)\\n", this->beneath ()->shortname ());',
 252         file=f,
 253     )
 254
 255     # Delegate to the beneath target.
 256     print("  ", file=f, end="")
 257     if return_type != "void":
 258         print("result = ", file=f, end="")
 259     print("this->beneath ()->" + name + " (", file=f, end="")
 260     print(", ".join(names), file=f, end="")
 261     print(");", file=f)
 262
 263     # Now print the arguments.
 264     print(
 265         '  gdb_printf (gdb_stdlog, "<- %s->'
 266         + name
 267         + ' (", this->beneath ()->shortname ());',
 268         file=f,
 269     )
 270     for i in range(len(argtypes)):
 271         if i > 0:
 272             print('  gdb_puts (", ", gdb_stdlog);', file=f)
 273         printer = munge_type(argtypes[i])
 274         print("  " + printer + " (" + names[i] + ");", file=f)
 275     if return_type != "void":
 276         print('  gdb_puts (") = ", gdb_stdlog);', file=f)
 277         printer = munge_type(return_type)
 278         print("  " + printer + " (result);", file=f)
 279         print('  gdb_puts ("\\n", gdb_stdlog);', file=f)
 280     else:
 281         print('  gdb_puts (")\\n", gdb_stdlog);', file=f)
 282
 283     if return_type != "void":
 284         print("  return result;", file=f)
 285
 286     print("}\n", file=f)
 287
 288
 289 def print_class(f, class_name, delegators, entries):
 290     print("struct " + class_name + " : public target_ops", file=f)
 291     print("{", file=f)
 292     print("  const target_info &info () const override;", file=f)
 293     print("", file=f)
 294     print("  strata stratum () const override;", file=f)
 295     print("", file=f)
 296
 297     for name in delegators:
 298         return_type = entries[name]["return_type"]
 299         argtypes = entries[name]["argtypes"]
 300         print("  ", file=f, end="")
 301         write_declaration(f, name, return_type, argtypes)
 302
 303     print("};\n", file=f)
 304
 305
 306 delegators = []
 307 entries = {}
 308 for current_line in scan_target_h():
 309     # See comments in scan_target_h.  Here we strip away the leading
 310     # and trailing whitespace.
 311     current_line = current_line.strip()
 312     m = METHOD.match(current_line)
 313     if not m:
 314         continue
 315     data = m.groupdict()
 316     data["argtypes"] = parse_argtypes(data["args"])
 317     data["return_type"] = data["return_type"].strip()
 318     entries[data["name"]] = data
 319
 320     delegators.append(data["name"])
 321
 322 with open("target-delegates.c", "w") as f:
 323     print(
 324         gdbcopyright.copyright(
 325             "make-target-delegates.py", "Boilerplate target methods for GDB"
 326         ),
 327         file=f,
 328     )
 329     print_class(f, "dummy_target", delegators, entries)
 330     print_class(f, "debug_target", delegators, entries)
 331
 332     for name in delegators:
 333         tdefault = entries[name]["default_arg"]
 334         return_type = entries[name]["return_type"]
 335         style = entries[name]["style"]
 336         argtypes = entries[name]["argtypes"]
 337
 338         write_delegator(f, name, return_type, argtypes)
 339         write_tdefault(f, tdefault, style, name, return_type, argtypes)
 340         write_debugmethod(f, tdefault, name, return_type, argtypes)