gdb/make-target-delegates.py

   1 #!/usr/bin/env python3
   2
   3 # Copyright (C) 2013-2023 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 from typing import Dict, List, TextIO
  25
  26 import gdbcopyright
  27
  28 # The line we search for in target.h that marks where we should start
  29 # looking for methods.
  30 TRIGGER = re.compile(r"^struct target_ops$")
  31 # The end of the methods part.
  32 ENDER = re.compile(r"^\s*};$")
  33
  34 # Match a C symbol.
  35 SYMBOL = "[a-zA-Z_][a-zA-Z0-9_]*"
  36 # Match the name part of a method in struct target_ops.
  37 NAME_PART = r"(?P<name>" + SYMBOL + r")\s"
  38 # Match the arguments to a method.
  39 ARGS_PART = r"(?P<args>\(.*\))"
  40 # We strip the indentation so here we only need the caret.
  41 INTRO_PART = r"^"
  42
  43 POINTER_PART = r"\s*(\*|\&)?\s*"
  44
  45 # Match a C++ symbol, including scope operators and template
  46 # parameters.  E.g., 'std::vector<something>'.
  47 CP_SYMBOL = r"[a-zA-Z_][a-zA-Z0-9_<>:]*"
  48 # Match the return type when it is "ordinary".
  49 SIMPLE_RETURN_PART = r"((struct|class|enum|union)\s+)?" + CP_SYMBOL
  50
  51 # Match a return type.
  52 RETURN_PART = r"((const|volatile)\s+)?(" + SIMPLE_RETURN_PART + ")" + POINTER_PART
  53
  54 # Match "virtual".
  55 VIRTUAL_PART = r"virtual\s"
  56
  57 # Match the TARGET_DEFAULT_* attribute for a method.
  58 TARGET_DEFAULT_PART = r"TARGET_DEFAULT_(?P<style>[A-Z_]+)\s*\((?P<default_arg>.*)\)"
  59
  60 # Match the arguments and trailing attribute of a method definition.
  61 # Note we don't match the trailing ";".
  62 METHOD_TRAILER = r"\s*" + TARGET_DEFAULT_PART + "$"
  63
  64 # Match an entire method definition.
  65 METHOD = re.compile(
  66     INTRO_PART
  67     + VIRTUAL_PART
  68     + "(?P<return_type>"
  69     + RETURN_PART
  70     + ")"
  71     + NAME_PART
  72     + ARGS_PART
  73     + METHOD_TRAILER
  74 )
  75
  76 # Regular expression used to dissect argument types.
  77 ARGTYPES = re.compile(
  78     "^("
  79     + r"(?P<E>enum\s+"
  80     + SYMBOL
  81     + r"\s*)("
  82     + SYMBOL
  83     + ")?"
  84     + r"|(?P<T>.*(enum\s+)?"
  85     + SYMBOL
  86     + r".*(\s|\*|&))"
  87     + SYMBOL
  88     + ")$"
  89 )
  90
  91 # Match TARGET_DEBUG_PRINTER in an argument type.
  92 # This must match the whole "sub-expression" including the parens.
  93 TARGET_DEBUG_PRINTER = r"\s*TARGET_DEBUG_PRINTER\s*\((?P<arg>[^)]*)\)\s*"
  94
  95
  96 class Entry:
  97     def __init__(
  98         self, argtypes: List[str], return_type: str, style: str, default_arg: str
  99     ):
 100         self.argtypes = argtypes
 101         self.return_type = return_type
 102         self.style = style
 103         self.default_arg = default_arg
 104
 105
 106 def scan_target_h():
 107     found_trigger = False
 108     all_the_text = ""
 109     with open("target.h", "r") as target_h:
 110         for line in target_h:
 111             line = line.strip()
 112             if not found_trigger:
 113                 if TRIGGER.match(line):
 114                     found_trigger = True
 115             elif "{" in line:
 116                 # Skip the open brace.
 117                 pass
 118             elif ENDER.match(line):
 119                 break
 120             else:
 121                 # Strip // comments.
 122                 line = re.split("//", line)[0]
 123                 all_the_text = all_the_text + " " + line
 124     if not found_trigger:
 125         raise RuntimeError("Could not find trigger line")
 126     # Now strip out the C comments.
 127     all_the_text = re.sub(r"/\*(.*?)\*/", "", all_the_text)
 128     # Replace sequences whitespace with a single space character.
 129     # We need the space because the method may have been split
 130     # between multiple lines, like e.g.:
 131     #
 132     #  virtual std::vector<long_type_name>
 133     #    my_long_method_name ()
 134     #    TARGET_DEFAULT_IGNORE ();
 135     #
 136     # If we didn't preserve the space, then we'd end up with:
 137     #
 138     #  virtual std::vector<long_type_name>my_long_method_name ()TARGET_DEFAULT_IGNORE ()
 139     #
 140     # ... which wouldn't later be parsed correctly.
 141     all_the_text = re.sub(r"\s+", " ", all_the_text)
 142     return all_the_text.split(";")
 143
 144
 145 # Parse arguments into a list.
 146 def parse_argtypes(typestr: str):
 147     # Remove the outer parens.
 148     typestr = re.sub(r"^\((.*)\)$", r"\1", typestr)
 149     result: list[str] = []
 150     for item in re.split(r",\s*", typestr):
 151         if item == "void" or item == "":
 152             continue
 153         m = ARGTYPES.match(item)
 154         if m:
 155             if m.group("E"):
 156                 onetype = m.group("E")
 157             else:
 158                 onetype = m.group("T")
 159         else:
 160             onetype = item
 161         result.append(onetype.strip())
 162     return result
 163
 164
 165 # Write function header given name, return type, and argtypes.
 166 # Returns a list of actual argument names.
 167 def write_function_header(
 168     f: TextIO, decl: bool, name: str, return_type: str, argtypes: List[str]
 169 ):
 170     print(return_type, file=f, end="")
 171     if decl:
 172         if not return_type.endswith("*"):
 173             print(" ", file=f, end="")
 174     else:
 175         print("", file=f)
 176     print(name + " (", file=f, end="")
 177     argdecls: list[str] = []
 178     actuals: list[str] = []
 179     for i in range(len(argtypes)):
 180         val = re.sub(TARGET_DEBUG_PRINTER, "", argtypes[i])
 181         if not val.endswith("*") and not val.endswith("&"):
 182             val = val + " "
 183         vname = "arg" + str(i)
 184         val = val + vname
 185         argdecls.append(val)
 186         actuals.append(vname)
 187     print(", ".join(argdecls) + ")", file=f, end="")
 188     if decl:
 189         print(" override;", file=f)
 190     else:
 191         print("\n{", file=f)
 192     return actuals
 193
 194
 195 # Write out a declaration.
 196 def write_declaration(f: TextIO, name: str, return_type: str, argtypes: List[str]):
 197     write_function_header(f, True, name, return_type, argtypes)
 198
 199
 200 # Write out a delegation function.
 201 def write_delegator(f: TextIO, name: str, return_type: str, argtypes: List[str]):
 202     print("", file=f)
 203     names = write_function_header(
 204         f, False, "target_ops::" + name, return_type, argtypes
 205     )
 206     print("  ", file=f, end="")
 207     if return_type != "void":
 208         print("return ", file=f, end="")
 209     print("this->beneath ()->" + name + " (", file=f, end="")
 210     print(", ".join(names), file=f, end="")
 211     print(");", file=f)
 212     print("}", file=f)
 213
 214
 215 # Write out a default function.
 216 def write_tdefault(
 217     f: TextIO,
 218     content: str,
 219     style: str,
 220     name: str,
 221     return_type: str,
 222     argtypes: List[str],
 223 ):
 224     print("", file=f)
 225     name = "dummy_target::" + name
 226     names = write_function_header(f, False, name, return_type, argtypes)
 227     if style == "FUNC":
 228         print("  ", file=f, end="")
 229         if return_type != "void":
 230             print("return ", file=f, end="")
 231         print(content + " (", file=f, end="")
 232         names.insert(0, "this")
 233         print(", ".join(names) + ");", file=f)
 234     elif style == "RETURN":
 235         print("  return " + content + ";", file=f)
 236     elif style == "NORETURN":
 237         print("  " + content + ";", file=f)
 238     elif style == "IGNORE":
 239         # Nothing.
 240         pass
 241     else:
 242         raise RuntimeError("unrecognized style: " + style)
 243     print("}", file=f)
 244
 245
 246 def munge_type(typename: str):
 247     m = re.search(TARGET_DEBUG_PRINTER, typename)
 248     if m:
 249         return m.group("arg")
 250     typename = typename.rstrip()
 251     # There's no reason to have these keywords in the name, and their
 252     # presence makes it harder to change styles.
 253     typename = re.sub("\\b(struct|enum|class|union) ", "", typename)
 254     typename = re.sub("[ ()<>:]", "_", typename)
 255     typename = re.sub("[*]", "p", typename)
 256     typename = re.sub("&", "r", typename)
 257     # Identifiers with double underscores are reserved to the C++
 258     # implementation.
 259     typename = re.sub("_+", "_", typename)
 260     # Avoid ending the function name with underscore, for
 261     # cosmetics.  Trailing underscores appear after munging types
 262     # with template parameters, like e.g. "foo<int>".
 263     typename = re.sub("_+$", "", typename)
 264     return "target_debug_print_" + typename
 265
 266
 267 # Write out a debug method.
 268 def write_debugmethod(
 269     f: TextIO, content: str, name: str, return_type: str, argtypes: List[str]
 270 ):
 271     print("", file=f)
 272     debugname = "debug_target::" + name
 273     names = write_function_header(f, False, debugname, return_type, argtypes)
 274     print(
 275         '  gdb_printf (gdb_stdlog, "-> %s->'
 276         + name
 277         + ' (...)\\n", this->beneath ()->shortname ());',
 278         file=f,
 279     )
 280
 281     # Delegate to the beneath target.
 282     if return_type != "void":
 283         print("  " + return_type + " result", file=f)
 284         print("    = ", file=f, end="")
 285     else:
 286         print("  ", file=f, end="")
 287     print("this->beneath ()->" + name + " (", file=f, end="")
 288     print(", ".join(names), file=f, end="")
 289     print(");", file=f)
 290
 291     # Now print the arguments.
 292     print(
 293         '  gdb_printf (gdb_stdlog, "<- %s->'
 294         + name
 295         + ' (", this->beneath ()->shortname ());',
 296         file=f,
 297     )
 298     for i in range(len(argtypes)):
 299         if i > 0:
 300             print('  gdb_puts (", ", gdb_stdlog);', file=f)
 301         printer = munge_type(argtypes[i])
 302         print("  " + printer + " (" + names[i] + ");", file=f)
 303     if return_type != "void":
 304         print('  gdb_puts (") = ", gdb_stdlog);', file=f)
 305         printer = munge_type(return_type)
 306         print("  " + printer + " (result);", file=f)
 307         print('  gdb_puts ("\\n", gdb_stdlog);', file=f)
 308     else:
 309         print('  gdb_puts (")\\n", gdb_stdlog);', file=f)
 310
 311     if return_type != "void":
 312         print("  return result;", file=f)
 313
 314     print("}", file=f)
 315
 316
 317 def print_class(
 318     f: TextIO,
 319     class_name: str,
 320     delegators: List[str],
 321     entries: Dict[str, Entry],
 322 ):
 323     print("", file=f)
 324     print("struct " + class_name + " : public target_ops", file=f)
 325     print("{", file=f)
 326     print("  const target_info &info () const override;", file=f)
 327     print("", file=f)
 328     print("  strata stratum () const override;", file=f)
 329     print("", file=f)
 330
 331     for name in delegators:
 332         print("  ", file=f, end="")
 333         entry = entries[name]
 334         write_declaration(f, name, entry.return_type, entry.argtypes)
 335
 336     print("};", file=f)
 337
 338
 339 delegators: List[str] = []
 340 entries: Dict[str, Entry] = {}
 341
 342 for current_line in scan_target_h():
 343     # See comments in scan_target_h.  Here we strip away the leading
 344     # and trailing whitespace.
 345     current_line = current_line.strip()
 346     m = METHOD.match(current_line)
 347     if not m:
 348         continue
 349     data = m.groupdict()
 350     name = data["name"]
 351     argtypes = parse_argtypes(data["args"])
 352     return_type = data["return_type"].strip()
 353     style = data["style"]
 354     default_arg = data["default_arg"]
 355     entries[name] = Entry(argtypes, return_type, style, default_arg)
 356
 357     delegators.append(name)
 358
 359 with open("target-delegates.c", "w") as f:
 360     print(
 361         gdbcopyright.copyright(
 362             "make-target-delegates.py", "Boilerplate target methods for GDB"
 363         ),
 364         file=f,
 365     )
 366     print_class(f, "dummy_target", delegators, entries)
 367     print_class(f, "debug_target", delegators, entries)
 368
 369     for name in delegators:
 370         entry = entries[name]
 371
 372         write_delegator(f, name, entry.return_type, entry.argtypes)
 373         write_tdefault(
 374             f,
 375             entry.default_arg,
 376             entry.style,
 377             name,
 378             entry.return_type,
 379             entry.argtypes,
 380         )
 381         write_debugmethod(
 382             f,
 383             entry.default_arg,
 384             name,
 385             entry.return_type,
 386             entry.argtypes,
 387         )