1 #!/usr/bin/env python 2 3 """ 4 Translate programs. 5 6 Copyright (C) 2015, 2016, 2017, 2018, 2023 Paul Boddie <paul@boddie.org.uk> 7 8 This program is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free Software 10 Foundation; either version 3 of the License, or (at your option) any later 11 version. 12 13 This program is distributed in the hope that it will be useful, but WITHOUT 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 15 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 16 details. 17 18 You should have received a copy of the GNU General Public License along with 19 this program. If not, see <http://www.gnu.org/licenses/>. 20 """ 21 22 from common import AccessLocation, CommonModule, CommonOutput, Location, \ 23 first, get_builtin_class, init_item, is_newer, \ 24 predefined_constants 25 from encoders import encode_access_instruction, encode_access_instruction_arg, \ 26 encode_function_pointer, encode_literal_instantiator, \ 27 encode_instantiator_pointer, encode_path, encode_symbol, \ 28 encode_type_attribute, is_type_attribute, \ 29 type_ops, typename_ops 30 from errors import InspectError, TranslateError 31 from os.path import exists, join 32 from os import makedirs 33 from referencing import Reference, combine_types 34 from results import Result 35 from transresults import TrConstantValueRef, TrInstanceRef, \ 36 TrLiteralSequenceRef, TrResolvedNameRef, \ 37 AliasResult, AttrResult, Expression, InstantiationResult, \ 38 InvocationResult, LogicalOperationResult, \ 39 LogicalResult, NegationResult, PredefinedConstantRef, \ 40 ReturnRef 41 from StringIO import StringIO 42 import compiler 43 import sys 44 45 class Translator(CommonOutput): 46 47 "A program translator." 48 49 def __init__(self, importer, deducer, optimiser, output): 50 self.importer = importer 51 self.deducer = deducer 52 self.optimiser = optimiser 53 self.output = output 54 55 def to_output(self, reset=False, debug=False, gc_sections=False): 56 57 "Write a program to the configured output directory." 58 59 # Make a directory for the final sources. 60 61 output = join(self.output, "src") 62 63 if not exists(output): 64 makedirs(output) 65 66 # Clean the output directory of irrelevant data. 67 68 self.check_output("debug=%r gc_sections=%r" % (debug, gc_sections)) 69 70 for module in self.importer.modules.values(): 71 output_filename = join(output, "%s.c" % module.name) 72 73 # Do not generate modules in the native package. They are provided 74 # by native functionality source files. 75 76 parts = module.name.split(".") 77 78 if parts[0] != "native" and \ 79 (reset or is_newer(module.filename, output_filename)): 80 81 tm = TranslatedModule(module.name, self.importer, self.deducer, self.optimiser) 82 tm.translate(module.filename, output_filename) 83 84 85 86 def make_expression(expr): 87 88 "Make a new expression from the existing 'expr'." 89 90 if isinstance(expr, Result): 91 return expr 92 else: 93 return Expression(str(expr)) 94 95 96 97 # The actual translation process itself. 98 99 class TranslatedModule(CommonModule): 100 101 "A module translator." 102 103 def __init__(self, name, importer, deducer, optimiser): 104 CommonModule.__init__(self, name, importer) 105 self.deducer = deducer 106 self.optimiser = optimiser 107 108 # Output stream. 109 110 self.out_toplevel = self.out = None 111 self.indent = 0 112 self.tabstop = " " 113 114 # Recorded namespaces. 115 116 self.namespaces = [] 117 self.in_conditional = False 118 self.in_parameter_list = False 119 120 # Exception raising adjustments. 121 122 self.in_try_finally = False 123 self.in_try_except = False 124 125 # Attribute access and accessor counting. 126 127 self.attr_accesses = {} 128 self.attr_accessors = {} 129 130 # Special variable usage. 131 132 self.temp_usage = {} 133 134 # Initialise some data used for attribute access generation. 135 136 self.init_substitutions() 137 138 def __repr__(self): 139 return "TranslatedModule(%r, %r)" % (self.name, self.importer) 140 141 def translate(self, filename, output_filename): 142 143 """ 144 Parse the file having the given 'filename', writing the translation to 145 the given 'output_filename'. 146 """ 147 148 self.parse_file(filename) 149 150 # Collect function namespaces for separate processing. 151 152 self.record_namespaces(self.astnode) 153 154 # Reset the lambda naming (in order to obtain the same names again) and 155 # translate the program. 156 157 self.reset_lambdas() 158 159 self.out_toplevel = self.out = open(output_filename, "w") 160 try: 161 self.start_output() 162 163 # Process namespaces, writing the translation. 164 165 for path, node in self.namespaces: 166 self.process_namespace(path, node) 167 168 # Process the module namespace including class namespaces. 169 170 self.process_namespace([], self.astnode) 171 172 finally: 173 self.out.close() 174 175 def have_object(self): 176 177 "Return whether a namespace is a recorded object." 178 179 return self.importer.objects.get(self.get_namespace_path()) 180 181 def get_builtin_class(self, name): 182 183 "Return a reference to the actual object providing 'name'." 184 185 return self.importer.get_object(get_builtin_class(name)) 186 187 def is_method(self, path): 188 189 "Return whether 'path' is a method." 190 191 class_name, method_name = path.rsplit(".", 1) 192 return self.importer.classes.has_key(class_name) and class_name or None 193 194 def in_method(self): 195 196 "Return whether the current namespace provides a method." 197 198 return self.in_function and self.is_method(self.get_namespace_path()) 199 200 # Namespace recording. 201 202 def record_namespaces(self, node): 203 204 "Process the program structure 'node', recording namespaces." 205 206 for n in node.getChildNodes(): 207 self.record_namespaces_in_node(n) 208 209 def record_namespaces_in_node(self, node): 210 211 "Process the program structure 'node', recording namespaces." 212 213 # Function namespaces within modules, classes and other functions. 214 # Functions appearing within conditional statements are given arbitrary 215 # names. 216 217 if isinstance(node, compiler.ast.Function): 218 self.record_function_node(node, (self.in_conditional or self.in_function) and self.get_lambda_name() or node.name) 219 220 elif isinstance(node, compiler.ast.Lambda): 221 self.record_function_node(node, self.get_lambda_name()) 222 223 # Classes are visited, but may be ignored if inside functions. 224 225 elif isinstance(node, compiler.ast.Class): 226 self.enter_namespace(node.name) 227 if self.have_object(): 228 self.record_namespaces(node) 229 self.exit_namespace() 230 231 # Conditional nodes are tracked so that function definitions may be 232 # handled. Since "for" loops are converted to "while" loops, they are 233 # included here. 234 235 elif isinstance(node, (compiler.ast.For, compiler.ast.If, compiler.ast.While)): 236 in_conditional = self.in_conditional 237 self.in_conditional = True 238 self.record_namespaces(node) 239 self.in_conditional = in_conditional 240 241 # All other nodes are processed depth-first. 242 243 else: 244 self.record_namespaces(node) 245 246 def record_function_node(self, n, name): 247 248 """ 249 Record the given function, lambda, if expression or list comprehension 250 node 'n' with the given 'name'. 251 """ 252 253 self.in_function = True 254 self.enter_namespace(name) 255 256 if self.have_object(): 257 258 # Record the namespace path and the node itself. 259 260 self.namespaces.append((self.namespace_path[:], n)) 261 self.record_namespaces_in_node(n.code) 262 263 self.exit_namespace() 264 self.in_function = False 265 266 # Constant referencing. 267 268 def get_literal_instance(self, n, name=None): 269 270 """ 271 For node 'n', return a reference for the type of the given 'name', or if 272 'name' is not specified, deduce the type from the value. 273 """ 274 275 # Handle stray None constants (Sliceobj seems to produce them). 276 277 if name is None and n.value is None: 278 return self.process_name_node(compiler.ast.Name("None")) 279 280 if name in ("dict", "list", "tuple"): 281 ref = self.get_builtin_class(name) 282 return self.process_literal_sequence_node(n, name, ref, TrLiteralSequenceRef) 283 else: 284 value, typename, encoding = self.get_constant_value(n.value, n.literals) 285 ref = self.get_builtin_class(typename) 286 value_type = ref.get_origin() 287 288 path = self.get_namespace_path() 289 290 # Obtain the local numbering of the constant and thus the 291 # locally-qualified name. 292 293 local_number = self.importer.all_constants[path][(value, value_type, encoding)] 294 constant_name = "$c%d" % local_number 295 objpath = self.get_object_path(constant_name) 296 297 # Obtain the unique identifier for the constant. 298 299 number = self.optimiser.constant_numbers[objpath] 300 return TrConstantValueRef(constant_name, ref.instance_of(), value, number) 301 302 # Namespace translation. 303 304 def process_namespace(self, path, node): 305 306 """ 307 Process the namespace for the given 'path' defined by the given 'node'. 308 """ 309 310 self.namespace_path = path 311 312 if isinstance(node, (compiler.ast.Function, compiler.ast.Lambda)): 313 self.in_function = True 314 self.process_function_body_node(node) 315 else: 316 self.in_function = False 317 self.function_target = 0 318 self.max_function_target = 0 319 self.context_index = 0 320 self.max_context_index = 0 321 self.accessor_index = 0 322 self.max_accessor_index = 0 323 self.start_module() 324 self.process_structure(node) 325 self.end_module() 326 327 def process_structure(self, node): 328 329 "Process the given 'node' or result." 330 331 # Handle processing requests on results. 332 333 if isinstance(node, Result): 334 return node 335 336 # Handle processing requests on nodes. 337 338 else: 339 l = CommonModule.process_structure(self, node) 340 341 # Return indications of return statement usage. 342 343 if l and isinstance(l[-1], ReturnRef): 344 return l[-1] 345 else: 346 return None 347 348 def process_structure_node(self, n): 349 350 "Process the individual node 'n'." 351 352 # Plain statements emit their expressions. 353 354 if isinstance(n, compiler.ast.Discard): 355 expr = self.process_structure_node(n.expr) 356 self.statement(expr) 357 358 # Module import declarations. 359 360 elif isinstance(n, compiler.ast.From): 361 self.process_from_node(n) 362 363 # Nodes using operator module functions. 364 365 elif isinstance(n, compiler.ast.Operator): 366 return self.process_operator_node(n) 367 368 elif isinstance(n, compiler.ast.AugAssign): 369 self.process_augassign_node(n) 370 371 elif isinstance(n, compiler.ast.Compare): 372 return self.process_compare_node(n) 373 374 elif isinstance(n, compiler.ast.Slice): 375 return self.process_slice_node(n) 376 377 elif isinstance(n, compiler.ast.Sliceobj): 378 return self.process_sliceobj_node(n) 379 380 elif isinstance(n, compiler.ast.Subscript): 381 return self.process_subscript_node(n) 382 383 # Classes are visited, but may be ignored if inside functions. 384 385 elif isinstance(n, compiler.ast.Class): 386 self.process_class_node(n) 387 388 # Functions within namespaces have any dynamic defaults initialised. 389 390 elif isinstance(n, compiler.ast.Function): 391 self.process_function_node(n) 392 393 # Lambdas are replaced with references to separately-generated 394 # functions. 395 396 elif isinstance(n, compiler.ast.Lambda): 397 return self.process_lambda_node(n) 398 399 # Assignments. 400 401 elif isinstance(n, compiler.ast.Assign): 402 403 # Handle each assignment node. 404 405 for node in n.nodes: 406 self.process_assignment_node(node, n.expr) 407 408 # Accesses. 409 410 elif isinstance(n, compiler.ast.Getattr): 411 return self.process_attribute_access(n) 412 413 # Names. 414 415 elif isinstance(n, compiler.ast.Name): 416 return self.process_name_node(n) 417 418 # Loops and conditionals. 419 420 elif isinstance(n, compiler.ast.For): 421 self.process_for_node(n) 422 423 elif isinstance(n, compiler.ast.While): 424 self.process_while_node(n) 425 426 elif isinstance(n, compiler.ast.If): 427 self.process_if_node(n) 428 429 elif isinstance(n, (compiler.ast.And, compiler.ast.Or)): 430 return self.process_logical_node(n) 431 432 elif isinstance(n, compiler.ast.Not): 433 return self.process_not_node(n) 434 435 # Exception control-flow tracking. 436 437 elif isinstance(n, compiler.ast.TryExcept): 438 self.process_try_node(n) 439 440 elif isinstance(n, compiler.ast.TryFinally): 441 self.process_try_finally_node(n) 442 443 # Control-flow modification statements. 444 445 elif isinstance(n, compiler.ast.Break): 446 self.writestmt("break;") 447 448 elif isinstance(n, compiler.ast.Continue): 449 self.writestmt("continue;") 450 451 elif isinstance(n, compiler.ast.Raise): 452 self.process_raise_node(n) 453 454 elif isinstance(n, compiler.ast.Return): 455 return self.process_return_node(n) 456 457 # Print statements. 458 459 elif isinstance(n, (compiler.ast.Print, compiler.ast.Printnl)): 460 self.statement(self.process_print_node(n)) 461 462 # Invocations. 463 464 elif isinstance(n, compiler.ast.CallFunc): 465 return self.process_invocation_node(n) 466 467 elif isinstance(n, compiler.ast.Keyword): 468 return self.process_structure_node(n.expr) 469 470 # Constant usage. 471 472 elif isinstance(n, compiler.ast.Const): 473 return self.get_literal_instance(n) 474 475 elif isinstance(n, compiler.ast.Dict): 476 return self.get_literal_instance(n, "dict") 477 478 elif isinstance(n, compiler.ast.List): 479 return self.get_literal_instance(n, "list") 480 481 elif isinstance(n, compiler.ast.Tuple): 482 return self.get_literal_instance(n, "tuple") 483 484 # All other nodes are processed depth-first. 485 486 else: 487 return self.process_structure(n) 488 489 def process_assignment_node(self, n, expr): 490 491 "Process the individual node 'n' to be assigned the contents of 'expr'." 492 493 # Names and attributes are assigned the entire expression. 494 495 if isinstance(n, compiler.ast.AssName): 496 name_ref = self.process_name_node(n, expr, True) 497 self.statement(name_ref) 498 499 # Employ guards after assignments if required. 500 501 if expr and name_ref.is_name(): 502 self.generate_guard(name_ref.name) 503 504 elif isinstance(n, compiler.ast.AssAttr): 505 in_assignment = self.in_assignment 506 self.in_assignment = self.process_structure_node(expr) 507 self.statement(self.process_attribute_access(n)) 508 self.in_assignment = in_assignment 509 510 # Lists and tuples are matched against the expression and their 511 # items assigned to expression items. 512 513 elif isinstance(n, (compiler.ast.AssList, compiler.ast.AssTuple)): 514 self.process_assignment_node_items(n, expr) 515 516 # Slices and subscripts are permitted within assignment nodes. 517 518 elif isinstance(n, compiler.ast.Slice): 519 self.statement(self.process_slice_node(n, expr)) 520 521 elif isinstance(n, compiler.ast.Subscript): 522 self.statement(self.process_subscript_node(n, expr)) 523 524 def process_attribute_access(self, n): 525 526 "Process the given attribute access node 'n'." 527 528 # Obtain any completed chain and return the reference to it. 529 530 attr_expr = self.process_attribute_chain(n) 531 if self.have_access_expression(n): 532 return attr_expr 533 534 # Where the start of the chain of attributes has been reached, process 535 # the complete access. 536 537 name_ref = attr_expr and attr_expr.is_name() and attr_expr 538 name = name_ref and self.get_name_for_tracking(name_ref.name, name_ref) or None 539 540 location = self.get_access_location(name, self.attrs) 541 refs = self.get_referenced_attributes(location) 542 543 # Generate access instructions. 544 545 subs = { 546 "<expr>" : attr_expr, 547 "<name>" : attr_expr, 548 "<assexpr>" : self.in_assignment, 549 } 550 551 subs.update(self.temp_subs) 552 subs.update(self.op_subs) 553 554 output = [] 555 substituted = set() 556 557 # The context set or retrieved will be that used by any enclosing 558 # invocation. 559 560 accessor_index = self.accessor_index 561 context_index = self.context_index 562 context_identity = None 563 context_identity_verified = False 564 final_identity = None 565 accessor_test = False 566 accessor_stored = False 567 568 # Obtain encoded versions of each instruction, accumulating temporary 569 # variables. 570 571 for instruction in self.deducer.access_instructions[location]: 572 573 # Intercept a special instruction identifying the context. 574 575 if instruction[0] in ("<context_identity>", "<context_identity_verified>"): 576 context_identity, _substituted = \ 577 encode_access_instruction_arg(instruction[1], subs, instruction[0], 578 accessor_index, context_index) 579 context_identity_verified = instruction[0] == "<context_identity_verified>" 580 continue 581 582 # Intercept a special instruction identifying the target. The value 583 # is not encoded since it is used internally. 584 585 elif instruction[0] == "<final_identity>": 586 final_identity = instruction[1] 587 continue 588 589 # Modify test instructions. 590 591 elif instruction[0] in typename_ops or instruction[0] in type_ops: 592 instruction = ("__to_error", instruction) 593 accessor_test = True 594 595 # Intercept accessor storage. 596 597 elif instruction[0] == "<set_accessor>": 598 accessor_stored = True 599 600 # Collect the encoded instruction, noting any temporary variables 601 # required by it. 602 603 encoded, _substituted = encode_access_instruction(instruction, subs, 604 accessor_index, context_index) 605 output.append(encoded) 606 substituted.update(_substituted) 607 608 # Record temporary name usage. 609 610 for sub in substituted: 611 if self.temp_subs.has_key(sub): 612 self.record_temp(self.temp_subs[sub]) 613 614 # Get full final identity details. 615 616 if final_identity and not refs: 617 refs = set([self.importer.identify(final_identity)]) 618 619 del self.attrs[0] 620 return AttrResult(output, refs, location, 621 context_identity, context_identity_verified, 622 accessor_test, accessor_stored) 623 624 def init_substitutions(self): 625 626 """ 627 Initialise substitutions, defining temporary variable mappings, some of 628 which are also used as substitutions, together with operation mappings 629 used as substitutions in instructions defined by the optimiser. 630 """ 631 632 self.temp_subs = { 633 634 # Substitutions used by instructions. 635 636 "<private_context>" : "__tmp_private_context", 637 "<target_accessor>" : "__tmp_target_value", 638 639 # Mappings to be replaced by those given below. 640 641 "<accessor>" : "__tmp_values", 642 "<context>" : "__tmp_contexts", 643 "<test_context_revert>" : "__tmp_contexts", 644 "<test_context_static>" : "__tmp_contexts", 645 "<set_context>" : "__tmp_contexts", 646 "<set_private_context>" : "__tmp_private_context", 647 "<set_accessor>" : "__tmp_values", 648 "<set_target_accessor>" : "__tmp_target_value", 649 } 650 651 self.op_subs = { 652 "<accessor>" : "__get_accessor", 653 "<context>" : "__get_context", 654 "<test_context_revert>" : "__test_context_revert", 655 "<test_context_static>" : "__test_context_static", 656 "<set_context>" : "__set_context", 657 "<set_private_context>" : "__set_private_context", 658 "<set_accessor>" : "__set_accessor", 659 "<set_target_accessor>" : "__set_target_accessor", 660 } 661 662 def get_referenced_attributes(self, location): 663 664 """ 665 Convert 'location' to the form used by the deducer and retrieve any 666 identified attributes. 667 """ 668 669 # Determine whether any deduced references refer to the accessed 670 # attribute. 671 672 attrnames = location.attrnames 673 attrnames = attrnames and attrnames.split(".") 674 remaining = attrnames and len(attrnames) > 1 675 676 access_location = self.deducer.const_accesses.get(location) 677 678 if remaining and not access_location: 679 return set() 680 681 return self.deducer.get_references_for_access(access_location or location) 682 683 def get_referenced_attribute_invocations(self, location): 684 685 """ 686 Convert 'location' to the form used by the deducer and retrieve any 687 identified attribute invocation details. 688 """ 689 690 access_location = self.deducer.const_accesses.get(location) 691 return self.deducer.reference_invocations_unsuitable.get(access_location or location) 692 693 def get_accessor_kinds(self, location): 694 695 "Return the accessor kinds for 'location'." 696 697 return self.deducer.accessor_kinds.get(location) 698 699 def get_access_location(self, name, attrnames=None): 700 701 """ 702 Using the current namespace, the given 'name', and the 'attrnames' 703 employed in an access, return the access location. 704 """ 705 706 path = self.get_path_for_access() 707 708 # Get the location used by the deducer and optimiser and find any 709 # recorded access. 710 711 attrnames = attrnames and ".".join(self.attrs) 712 access_number = self.get_access_number(path, name, attrnames) 713 self.update_access_number(path, name, attrnames) 714 return AccessLocation(path, name, attrnames, access_number) 715 716 def get_access_number(self, path, name, attrnames): 717 access = name, attrnames 718 if self.attr_accesses.has_key(path) and self.attr_accesses[path].has_key(access): 719 return self.attr_accesses[path][access] 720 else: 721 return 0 722 723 def update_access_number(self, path, name, attrnames): 724 access = name, attrnames 725 if name: 726 init_item(self.attr_accesses, path, dict) 727 init_item(self.attr_accesses[path], access, lambda: 0) 728 self.attr_accesses[path][access] += 1 729 730 def get_accessor_location(self, name): 731 732 """ 733 Using the current namespace and the given 'name', return the accessor 734 location. 735 """ 736 737 path = self.get_path_for_access() 738 739 # Get the location used by the deducer and optimiser and find any 740 # recorded accessor. 741 742 version = self.get_accessor_number(path, name) 743 self.update_accessor_number(path, name) 744 return Location(path, name, None, version) 745 746 def get_accessor_number(self, path, name): 747 if self.attr_accessors.has_key(path) and self.attr_accessors[path].has_key(name): 748 return self.attr_accessors[path][name] 749 else: 750 return 0 751 752 def update_accessor_number(self, path, name): 753 if name: 754 init_item(self.attr_accessors, path, dict) 755 init_item(self.attr_accessors[path], name, lambda: 0) 756 self.attr_accessors[path][name] += 1 757 758 def process_class_node(self, n): 759 760 "Process the given class node 'n'." 761 762 class_name = self.get_object_path(n.name) 763 764 # Where a class is set conditionally or where the name may refer to 765 # different values, assign the name. 766 767 ref = self.importer.identify(class_name) 768 769 if not ref.static(): 770 self.process_assignment_for_object(n.name, 771 make_expression("__ATTRVALUE(&%s)" % encode_path(class_name))) 772 773 self.enter_namespace(n.name) 774 775 if self.have_object(): 776 self.write_comment("Class: %s" % class_name) 777 778 self.initialise_inherited_members(class_name) 779 780 self.process_structure(n) 781 self.write_comment("End class: %s" % class_name) 782 783 self.exit_namespace() 784 785 def initialise_inherited_members(self, class_name): 786 787 "Initialise members of 'class_name' inherited from its ancestors." 788 789 for name, path in self.importer.all_class_attrs[class_name].items(): 790 target = "%s.%s" % (class_name, name) 791 792 # Ignore attributes with definitions. 793 794 ref = self.importer.identify(target) 795 if ref: 796 continue 797 798 # Ignore special type attributes. 799 800 if is_type_attribute(name): 801 continue 802 803 # Reference inherited attributes. 804 805 ref = self.importer.identify(path) 806 if ref and not ref.static(): 807 parent, attrname = path.rsplit(".", 1) 808 809 self.writestmt("__store_via_object(&%s, %s, __load_via_object(&%s, %s));" % ( 810 encode_path(class_name), name, 811 encode_path(parent), attrname 812 )) 813 814 def process_from_node(self, n): 815 816 "Process the given node 'n', importing from another module." 817 818 path = self.get_namespace_path() 819 820 # Attempt to obtain the referenced objects. 821 822 for name, alias in n.names: 823 if name == "*": 824 raise InspectError("Only explicitly specified names can be imported from modules.", path, n) 825 826 # Obtain the path of the assigned name. 827 828 objpath = self.get_object_path(alias or name) 829 830 # Obtain the identity of the name. 831 832 ref = self.importer.identify(objpath) 833 834 # Where the name is not static, assign the value. 835 836 if ref and not ref.static() and ref.get_name(): 837 self.writestmt("%s;" % 838 TrResolvedNameRef(alias or name, Reference("<var>", None, objpath), 839 expr=TrResolvedNameRef(name, ref))) 840 841 def process_function_body_node(self, n): 842 843 """ 844 Process the given function, lambda, if expression or list comprehension 845 node 'n', generating the body. 846 """ 847 848 function_name = self.get_namespace_path() 849 self.start_function(function_name) 850 851 # Process the function body. 852 853 in_conditional = self.in_conditional 854 self.in_conditional = False 855 self.function_target = 0 856 self.max_function_target = 0 857 self.context_index = 0 858 self.max_context_index = 0 859 self.accessor_index = 0 860 self.max_accessor_index = 0 861 self.result_target = 0 862 self.max_result_target = 0 863 self.result_target_name = None 864 865 # Volatile locals for exception handling. 866 867 self.volatile_locals = set() 868 869 # Process any guards defined for the parameters. 870 871 for name in self.importer.function_parameters.get(function_name): 872 self.generate_guard(name) 873 874 # Also support self in methods, since some mix-in methods may only work 875 # with certain descendant classes. 876 877 if self.in_method(): 878 self.generate_guard("self") 879 880 # Make assignments for .name entries in the parameters, provided this is 881 # a method. 882 883 if self.in_method(): 884 for name in self.importer.function_attr_initialisers.get(function_name) or []: 885 self.process_assignment_node( 886 compiler.ast.AssAttr(compiler.ast.Name("self"), name, "OP_ASSIGN"), 887 compiler.ast.Name(name)) 888 889 # Produce the body and any additional return statement. 890 891 expr = self.process_structure_node(n.code) or \ 892 self.in_method() and \ 893 function_name.rsplit(".", 1)[-1] == "__init__" and \ 894 TrResolvedNameRef("self", self.importer.function_locals[function_name]["self"]) or \ 895 PredefinedConstantRef("None") 896 897 if not isinstance(expr, ReturnRef): 898 self.writestmt("return %s;" % expr) 899 900 self.in_conditional = in_conditional 901 902 self.end_function(function_name) 903 904 def generate_guard(self, name): 905 906 """ 907 Get the accessor details for 'name', found in the current namespace, and 908 generate any guards defined for it. 909 """ 910 911 # Obtain the location, keeping track of assignment versions. 912 913 location = self.get_accessor_location(name) 914 test = self.deducer.accessor_guard_tests.get(location) 915 916 # Generate any guard from the deduced information. 917 918 if test: 919 guard, guard_type = test 920 921 if guard == "specific": 922 ref = first(self.deducer.accessor_all_types[location]) 923 argstr = "&%s" % encode_path(ref.get_origin()) 924 elif guard == "common": 925 ref = first(self.deducer.accessor_all_general_types[location]) 926 argstr = encode_path(encode_type_attribute(ref.get_origin())) 927 else: 928 return 929 930 # Write a test that raises a TypeError upon failure. 931 932 self.writestmt("if (!__test_%s_%s(__VALUE(%s), %s)) __raise_type_error();" % ( 933 guard, guard_type, encode_path(name), argstr)) 934 935 def process_function_node(self, n): 936 937 """ 938 Process the given function, lambda, if expression or list comprehension 939 node 'n', generating any initialisation statements. 940 """ 941 942 # Where a function is declared conditionally, use a separate name for 943 # the definition, and assign the definition to the stated name. 944 945 original_name = n.name 946 947 if self.in_conditional or self.in_function: 948 name = self.get_lambda_name() 949 else: 950 name = n.name 951 952 objpath = self.get_object_path(name) 953 954 # Obtain details of the defaults. 955 956 defaults = self.process_function_defaults(n, name, objpath) 957 if defaults: 958 for default in defaults: 959 self.writeline("%s;" % default) 960 961 # Where a function is set conditionally or where the name may refer to 962 # different values, assign the name. 963 964 ref = self.importer.identify(objpath) 965 966 if self.in_conditional or self.in_function: 967 self.process_assignment_for_object(original_name, compiler.ast.Name(name)) 968 elif not ref.static(): 969 context = self.is_method(objpath) 970 971 self.process_assignment_for_object(original_name, 972 make_expression("__ATTRVALUE(&%s)" % encode_path(objpath))) 973 974 def process_function_defaults(self, n, name, objpath, instance_name=None): 975 976 """ 977 Process the given function or lambda node 'n', initialising defaults 978 that are dynamically set. The given 'name' indicates the name of the 979 function. The given 'objpath' indicates the origin of the function. 980 The given 'instance_name' indicates the name of any separate instance 981 of the function created to hold the defaults. 982 983 Return a list of operations setting defaults on a function instance. 984 """ 985 986 function_name = self.get_object_path(name) 987 function_defaults = self.importer.function_defaults.get(function_name) 988 if not function_defaults: 989 return None 990 991 # Determine whether any unidentified defaults are involved. 992 993 for argname, default in function_defaults: 994 if not default.static(): 995 break 996 else: 997 return None 998 999 # Handle bound methods. 1000 1001 if not instance_name: 1002 instance_name = "&%s" % encode_path(objpath) 1003 else: 1004 instance_name = "__VALUE(%s)" % instance_name 1005 1006 # Where defaults are involved but cannot be identified, obtain a new 1007 # instance of the lambda and populate the defaults. 1008 1009 defaults = [] 1010 1011 # Join the original defaults with the inspected defaults. 1012 1013 original_defaults = [(argname, default) for (argname, default) in compiler.ast.get_defaults(n) if default] 1014 1015 for i, (original, inspected) in enumerate(map(None, original_defaults, function_defaults)): 1016 1017 # Obtain any reference for the default. 1018 1019 if original: 1020 argname, default = original 1021 name_ref = self.process_structure_node(default) 1022 elif inspected: 1023 argname, default = inspected 1024 name_ref = TrResolvedNameRef(argname, default) 1025 else: 1026 continue 1027 1028 # Generate default initialisers except when constants are employed. 1029 # Constants should be used when populating the function structures. 1030 1031 if name_ref and not isinstance(name_ref, TrConstantValueRef): 1032 defaults.append("__SETDEFAULT(%s, %s, %s)" % (instance_name, i, name_ref)) 1033 1034 return defaults 1035 1036 def process_if_node(self, n): 1037 1038 """ 1039 Process the given "if" node 'n'. 1040 """ 1041 1042 first = True 1043 for test, body in n.tests: 1044 test_ref = self.process_structure_node(test) 1045 self.start_if(first, test_ref) 1046 1047 in_conditional = self.in_conditional 1048 self.in_conditional = True 1049 self.process_structure_node(body) 1050 self.in_conditional = in_conditional 1051 1052 self.end_if() 1053 first = False 1054 1055 if n.else_: 1056 self.start_else() 1057 self.process_structure_node(n.else_) 1058 self.end_else() 1059 1060 print >>self.out 1061 1062 def process_invocation_node(self, n): 1063 1064 "Process the given invocation node 'n'." 1065 1066 # Process the expression. 1067 1068 expr = self.process_structure_node(n.node) 1069 1070 # Obtain details of the invocation expression. 1071 1072 objpath = expr.get_origin() 1073 location = expr.access_location() 1074 refs = expr.references() 1075 1076 # Identified target details. 1077 1078 target = None 1079 target_structure = None 1080 1081 # Specific function target information. 1082 1083 function = None 1084 1085 # Instantiation involvement. 1086 1087 instantiation = False 1088 literal_instantiation = False 1089 1090 # Invocation requirements. 1091 1092 context_required = True 1093 have_access_context = isinstance(expr, AttrResult) 1094 1095 # The context identity is merely the thing providing the context. 1096 # A verified context is one that does not need further testing for 1097 # suitability. 1098 1099 context_identity = have_access_context and expr.context() 1100 context_verified = have_access_context and expr.context_verified() 1101 1102 # The presence of any test operations in the accessor expression. 1103 # With such operations present, the expression cannot be eliminated. 1104 1105 tests_accessor = have_access_context and expr.tests_accessor() 1106 stores_accessor = have_access_context and expr.stores_accessor() 1107 1108 # Parameter details and parameter list dimensions. 1109 1110 parameters = None 1111 num_parameters = None 1112 num_defaults = None 1113 1114 # Obtain details of the callable and of its parameters. 1115 1116 # Literals may be instantiated specially. 1117 1118 if expr.is_name() and expr.name.startswith("$L") and objpath: 1119 instantiation = literal_instantiation = objpath 1120 target = encode_literal_instantiator(objpath) 1121 context_required = False 1122 1123 # Identified targets employ function pointers directly. 1124 1125 elif objpath: 1126 parameters = self.importer.function_parameters.get(objpath) 1127 function_defaults = self.importer.function_defaults.get(objpath) 1128 num_parameters = parameters and len(parameters) or 0 1129 num_defaults = function_defaults and len(function_defaults) or 0 1130 1131 # Class invocation involves instantiators. 1132 1133 if expr.has_kind("<class>"): 1134 instantiation = objpath 1135 target = encode_instantiator_pointer(objpath) 1136 init_ref = self.importer.all_class_attrs[objpath]["__init__"] 1137 target_structure = "&%s" % encode_path(init_ref) 1138 context_required = False 1139 1140 # Only plain functions and bound methods employ function pointers. 1141 1142 elif expr.has_kind("<function>"): 1143 function = objpath 1144 1145 # Test for functions and methods. 1146 1147 context_required = self.is_method(objpath) 1148 1149 accessor_kinds = location and self.get_accessor_kinds(location) 1150 1151 instance_accessor = accessor_kinds and \ 1152 len(accessor_kinds) == 1 and \ 1153 first(accessor_kinds) == "<instance>" 1154 1155 # Only identify certain bound methods or functions. 1156 1157 if not context_required or instance_accessor: 1158 target = encode_function_pointer(objpath) 1159 1160 # Access bound method defaults even if it is not clear whether 1161 # the accessor is appropriate. 1162 1163 target_structure = "&%s" % encode_path(objpath) 1164 1165 # Other targets are retrieved at run-time. 1166 1167 else: 1168 if location: 1169 attrnames = location.attrnames 1170 attrname = attrnames and attrnames.rsplit(".", 1)[-1] 1171 1172 # Determine common aspects of any identifiable targets. 1173 1174 if attrname or refs: 1175 all_params = set() 1176 all_defaults = set() 1177 min_params = set() 1178 max_params = set() 1179 1180 # Employ references from the expression or find all 1181 # possible attributes for the given attribute name. 1182 1183 refs = refs or self.get_attributes_for_attrname(attrname) 1184 1185 # Obtain parameters and defaults for each possible target. 1186 1187 for ref in refs: 1188 origin = ref.get_origin() 1189 params = self.importer.function_parameters.get(origin) 1190 1191 defaults = self.importer.function_defaults.get(origin) 1192 if defaults is not None: 1193 all_defaults.add(tuple(defaults)) 1194 1195 if params is not None: 1196 all_params.add(tuple(params)) 1197 min_params.add(len(params) - (defaults and len(defaults) or 0)) 1198 max_params.add(len(params)) 1199 else: 1200 refs = set() 1201 break 1202 1203 # Where the parameters and defaults are always the same, 1204 # permit populating them in advance. 1205 1206 if refs: 1207 if self.uses_keyword_arguments(n): 1208 if len(all_params) == 1 and (not all_defaults or len(all_defaults) == 1): 1209 parameters = first(all_params) 1210 function_defaults = all_defaults and first(all_defaults) or [] 1211 num_parameters = parameters and len(parameters) or 0 1212 num_defaults = function_defaults and len(function_defaults) or 0 1213 else: 1214 if len(min_params) == 1 and len(max_params) == 1: 1215 num_parameters = first(max_params) 1216 num_defaults = first(max_params) - first(min_params) 1217 1218 # Some information about the target may be available and be used to 1219 # provide warnings about argument compatibility. 1220 1221 if self.importer.give_warning("args"): 1222 unsuitable = self.get_referenced_attribute_invocations(location) 1223 1224 if unsuitable: 1225 for ref in unsuitable: 1226 _objpath = ref.get_origin() 1227 print >>sys.stderr, \ 1228 "In %s, at line %d, inappropriate number of " \ 1229 "arguments given. Need %d arguments to call %s." % ( 1230 self.get_namespace_path(), n.lineno, 1231 len(self.importer.function_parameters[_objpath]), 1232 _objpath) 1233 1234 # Logical statement about available parameter information. 1235 1236 known_parameters = num_parameters is not None 1237 1238 # The source of context information: target or temporary. 1239 1240 need_context_target = context_required and not have_access_context 1241 1242 need_context_stored = context_required and context_identity and \ 1243 context_identity.startswith("__get_context") 1244 1245 # Determine any readily-accessible target identity. 1246 1247 target_named = expr.is_name() and str(expr) or None 1248 target_identity = target or target_named 1249 1250 # Use of target information to populate defaults. 1251 1252 defaults_target_var = not (parameters and function_defaults is not None) and \ 1253 known_parameters and len(n.args) < num_parameters 1254 1255 # Use of a temporary target variable in these situations: 1256 # 1257 # A target provided by an expression needed for defaults. 1258 # 1259 # A target providing the context but not using a name to do so. 1260 # 1261 # A target expression involving the definition of a context which may 1262 # then be evaluated and stored to ensure that the context is available 1263 # during argument evaluation. 1264 # 1265 # An expression featuring an accessor test. 1266 1267 need_target_stored = defaults_target_var and not target_identity or \ 1268 need_context_target and not target_identity or \ 1269 need_context_stored or \ 1270 tests_accessor and not target 1271 1272 # Define stored target details. 1273 1274 target_stored = "__tmp_targets[%d]" % self.function_target 1275 target_var = need_target_stored and target_stored or target_identity 1276 1277 if need_target_stored: 1278 self.record_temp("__tmp_targets") 1279 1280 if need_context_stored: 1281 self.record_temp("__tmp_contexts") 1282 1283 if stores_accessor: 1284 self.record_temp("__tmp_values") 1285 1286 # Employ result targets only in functions. 1287 1288 if self.in_function: 1289 if self.result_target_name: 1290 result_target = self.result_target_name 1291 self.result_target_name = None 1292 else: 1293 result_target = "__tmp_results[%d]" % self.result_target 1294 self.record_temp("__tmp_results") 1295 self.next_result() 1296 else: 1297 result_target = "__NULL" 1298 1299 # Arguments are presented in a temporary frame array with any context 1300 # always being the first argument. Where it would be unused, it may be 1301 # set to null. 1302 1303 if context_required: 1304 if have_access_context: 1305 context_arg = context_identity 1306 else: 1307 context_arg = "__CONTEXT_AS_VALUE(%s)" % target_var 1308 else: 1309 context_arg = "__NULL" 1310 1311 # Start with result target and context arguments for each invocation. 1312 1313 args = [result_target, context_arg] 1314 argstart = 2 1315 1316 # Complete the array with null values, permitting tests for a complete 1317 # set of arguments. 1318 1319 args += [None] * (num_parameters is None and len(n.args) or num_parameters is not None and num_parameters or 0) 1320 kwcodes = [] 1321 kwargs = [] 1322 1323 # Any invocations in the arguments will store target details in a 1324 # different location. 1325 1326 function_target = self.function_target 1327 context_index = self.context_index 1328 accessor_index = self.accessor_index 1329 1330 if need_target_stored: 1331 self.next_target() 1332 1333 if need_context_stored: 1334 self.next_context() 1335 1336 if stores_accessor: 1337 self.next_accessor() 1338 1339 in_parameter_list = self.in_parameter_list 1340 self.in_parameter_list = True 1341 1342 for i, arg in enumerate(n.args): 1343 argexpr = self.process_structure_node(arg) 1344 1345 # Convert any attributes indicating value replacement. 1346 1347 if isinstance(argexpr, InvocationResult): 1348 argexprstr = "__to_arg(%s)" % argexpr 1349 else: 1350 argexprstr = str(argexpr) 1351 1352 # Store a keyword argument, either in the argument list or 1353 # in a separate keyword argument list for subsequent lookup. 1354 1355 if isinstance(arg, compiler.ast.Keyword): 1356 1357 # With knowledge of the target, store the keyword 1358 # argument directly. 1359 1360 if parameters: 1361 try: 1362 argnum = parameters.index(arg.name) 1363 except ValueError: 1364 raise TranslateError("Argument %s is not recognised." % arg.name, 1365 self.get_namespace_path(), n) 1366 args[argnum+argstart] = argexprstr 1367 1368 # Otherwise, store the details in a separate collection. 1369 1370 else: 1371 kwargs.append(argexprstr) 1372 kwcodes.append("{%s, %s}" % ( 1373 encode_ppos(arg.name), encode_pcode(arg.name))) 1374 1375 # Store non-keyword arguments in the argument list, rejecting 1376 # superfluous arguments. 1377 1378 else: 1379 try: 1380 args[i+argstart] = argexprstr 1381 except IndexError: 1382 raise TranslateError("Too many arguments specified.", 1383 self.get_namespace_path(), n) 1384 1385 # Reference the current target again. 1386 1387 self.in_parameter_list = in_parameter_list 1388 1389 if not self.in_parameter_list: 1390 self.function_target = function_target 1391 self.context_index = context_index 1392 self.accessor_index = accessor_index 1393 1394 # Defaults are added to the frame where arguments are missing. 1395 1396 if parameters and function_defaults is not None: 1397 1398 # Visit each default and set any missing arguments. Where keyword 1399 # arguments have been used, the defaults must be inspected and, if 1400 # necessary, inserted into gaps in the argument list. 1401 1402 for i, (argname, default) in enumerate(function_defaults): 1403 argnum = parameters.index(argname) 1404 if not args[argnum+argstart]: 1405 args[argnum+argstart] = "__GETDEFAULT(%s, %d)" % (target_structure, i) 1406 1407 elif known_parameters: 1408 1409 # No specific parameter details are provided, but no keyword 1410 # arguments are used. Thus, defaults can be supplied using position 1411 # information only. 1412 1413 i = len(n.args) 1414 pos = i - (num_parameters - num_defaults) 1415 while i < num_parameters: 1416 args[i+argstart] = "__GETDEFAULT(%s.value, %d)" % (target_var, pos) 1417 i += 1 1418 pos += 1 1419 1420 # Test for missing arguments. 1421 1422 if None in args: 1423 raise TranslateError("Not all arguments supplied.", 1424 self.get_namespace_path(), n) 1425 1426 # Encode the arguments. 1427 1428 # Where literal instantiation is occurring, add an argument indicating 1429 # the number of values. The result target and context are excluded. 1430 1431 if literal_instantiation: 1432 argstr = "%d, %s" % (len(args) - 2, ", ".join(args[2:])) 1433 else: 1434 argstr = ", ".join(args) 1435 1436 kwargstr = kwargs and ("__ARGS(%s)" % ", ".join(kwargs)) or "0" 1437 kwcodestr = kwcodes and ("__KWARGS(%s)" % ", ".join(kwcodes)) or "0" 1438 1439 # First, the invocation expression is presented. 1440 1441 stages = [] 1442 emit = stages.append 1443 1444 # Assign and yield any stored target. 1445 # The context may be set in the expression. 1446 1447 if need_target_stored: 1448 emit("%s = %s" % (target_var, expr)) 1449 target_expr = target_var 1450 1451 # Otherwise, retain the expression for later use. 1452 1453 else: 1454 target_expr = str(expr) 1455 1456 # Any specific callable is then obtained for invocation. 1457 1458 if target: 1459 1460 # An expression involving a test of the accessor providing the target. 1461 # This must be emitted in order to perform the test. 1462 1463 if tests_accessor: 1464 emit(str(expr)) 1465 1466 emit(target) 1467 1468 # Methods accessed via unidentified accessors are obtained for 1469 # invocation. 1470 1471 elif function: 1472 if context_required: 1473 1474 # Avoid further context testing if appropriate. 1475 1476 if have_access_context and context_verified: 1477 emit("__get_function_member(%s)" % target_expr) 1478 1479 # Otherwise, test the context for the function/method. 1480 1481 else: 1482 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1483 else: 1484 emit("_get_function_member(%s)" % target_expr) 1485 1486 # With known parameters, the target can be tested. 1487 1488 elif known_parameters: 1489 if self.always_callable(refs): 1490 if context_verified: 1491 emit("__get_function_member(%s)" % target_expr) 1492 else: 1493 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1494 else: 1495 emit("__check_and_get_function(%s, %s)" % (context_arg, target_expr)) 1496 1497 # With a known target, the function is obtained directly and called. 1498 # By putting the invocation at the end of the final element in the 1499 # instruction sequence (the stages), the result becomes the result of 1500 # the sequence. Moreover, the parameters become part of the sequence 1501 # and thereby participate in a guaranteed evaluation order. 1502 1503 if target or function or known_parameters: 1504 stages[-1] += "(%s)" % argstr 1505 if instantiation: 1506 return InstantiationResult(instantiation, stages) 1507 else: 1508 return InvocationResult(stages) 1509 1510 # With unknown targets, the generic invocation function is applied to 1511 # the callable and argument collections. 1512 1513 else: 1514 emit("__invoke(\n%s,\n%d, %d, %s, %s,\n%d, %s\n)" % ( 1515 target_expr, 1516 self.always_callable(refs) and 1 or 0, 1517 len(kwargs), kwcodestr, kwargstr, 1518 len(args), "__ARGS(%s)" % argstr)) 1519 return InvocationResult(stages) 1520 1521 def next_result(self): 1522 1523 "Allocate the next result target storage." 1524 1525 self.result_target += 1 1526 self.max_result_target = max(self.result_target, self.max_result_target) 1527 1528 def next_target(self): 1529 1530 "Allocate the next function target storage." 1531 1532 self.function_target += 1 1533 self.max_function_target = max(self.function_target, self.max_function_target) 1534 1535 def next_context(self): 1536 1537 "Allocate the next context value storage." 1538 1539 self.context_index += 1 1540 self.max_context_index = max(self.context_index, self.max_context_index) 1541 1542 def next_accessor(self): 1543 1544 "Allocate the next accessor value storage." 1545 1546 self.accessor_index += 1 1547 self.max_accessor_index = max(self.accessor_index, self.max_accessor_index) 1548 1549 def always_callable(self, refs): 1550 1551 "Determine whether all 'refs' are callable." 1552 1553 if not refs: 1554 return False 1555 1556 for ref in refs: 1557 if not ref.has_kind("<function>") and not self.importer.get_attributes(ref, "__fn__"): 1558 return False 1559 1560 return True 1561 1562 def need_default_arguments(self, objpath, nargs): 1563 1564 """ 1565 Return whether any default arguments are needed when invoking the object 1566 given by 'objpath'. 1567 """ 1568 1569 parameters = self.importer.function_parameters.get(objpath) 1570 return nargs < len(parameters) 1571 1572 def uses_keyword_arguments(self, n): 1573 1574 "Return whether invocation node 'n' uses keyword arguments." 1575 1576 for arg in enumerate(n.args): 1577 if isinstance(arg, compiler.ast.Keyword): 1578 return True 1579 1580 return False 1581 1582 def get_attributes_for_attrname(self, attrname): 1583 1584 "Return a set of all attributes exposed by 'attrname'." 1585 1586 usage = [(attrname, True, False)] 1587 class_types = self.deducer.get_class_types_for_usage(usage) 1588 instance_types = self.deducer.get_instance_types_for_usage(usage) 1589 module_types = self.deducer.get_module_types_for_usage(usage) 1590 attrs = set() 1591 1592 for ref in combine_types(class_types, instance_types, module_types): 1593 attrs.update(self.importer.get_attributes(ref, attrname)) 1594 1595 return attrs 1596 1597 def process_lambda_node(self, n): 1598 1599 "Process the given lambda node 'n'." 1600 1601 name = self.get_lambda_name() 1602 function_name = self.get_object_path(name) 1603 instance_name = "__get_accessor(%d)" % self.accessor_index 1604 1605 defaults = self.process_function_defaults(n, name, function_name, instance_name) 1606 1607 # Without defaults, produce an attribute referring to the function. 1608 1609 if not defaults: 1610 return make_expression("__ATTRVALUE(&%s)" % encode_path(function_name)) 1611 1612 # With defaults, copy the function structure and set the defaults on the 1613 # copy. 1614 1615 else: 1616 self.record_temp("__tmp_values") 1617 return make_expression("""\ 1618 (__set_accessor(%d, __ATTRVALUE(__COPY(&%s, sizeof(%s)))), 1619 %s, 1620 __get_accessor(%d))""" % ( 1621 self.accessor_index, 1622 encode_path(function_name), 1623 encode_symbol("obj", function_name), 1624 ", ".join(defaults), 1625 self.accessor_index)) 1626 1627 def process_logical_node(self, n): 1628 1629 "Process the given operator node 'n'." 1630 1631 self.record_temp("__tmp_result") 1632 1633 conjunction = isinstance(n, compiler.ast.And) 1634 results = [] 1635 1636 for node in n.nodes: 1637 results.append(self.process_structure_node(node)) 1638 1639 return LogicalOperationResult(results, conjunction) 1640 1641 def process_name_node(self, n, expr=None, process_expr=False): 1642 1643 "Process the given name node 'n' with the optional assignment 'expr'." 1644 1645 # Determine whether the name refers to a static external entity. 1646 1647 if n.name in predefined_constants: 1648 return PredefinedConstantRef(n.name, expr) 1649 1650 # Convert literal references, operator function names, and print 1651 # function names to references. 1652 1653 elif n.name.startswith("$L") or n.name.startswith("$op") or \ 1654 n.name.startswith("$seq") or n.name.startswith("$print"): 1655 1656 ref, paths = self.importer.get_module(self.name).special[n.name] 1657 return TrResolvedNameRef(n.name, ref) 1658 1659 # Get the appropriate name for the name reference, using the same method 1660 # as in the inspector. 1661 1662 path = self.get_namespace_path() 1663 objpath = self.get_object_path(n.name) 1664 1665 # Determine any assigned globals. 1666 1667 globals = self.importer.get_module(self.name).scope_globals.get(path) 1668 1669 # Explicitly declared globals. 1670 1671 if globals and n.name in globals: 1672 objpath = self.get_global_path(n.name) 1673 is_global = True 1674 1675 # Implicitly referenced globals in functions. 1676 1677 elif self.in_function: 1678 is_global = n.name not in self.importer.function_locals[path] 1679 1680 # Implicitly referenced globals elsewhere. 1681 1682 else: 1683 namespace = self.importer.identify(path) 1684 is_global = not self.importer.get_attributes(namespace, n.name) 1685 1686 # Get the static identity of the name. 1687 1688 ref = self.importer.identify(objpath) 1689 if ref and not ref.get_name(): 1690 ref = ref.alias(objpath) 1691 1692 # Obtain any resolved names for non-assignment names. 1693 1694 if not expr and not ref and self.in_function: 1695 locals = self.importer.function_locals.get(path) 1696 ref = locals and locals.get(n.name) 1697 1698 # Find any invocation or alias details. 1699 1700 name = self.get_name_for_tracking(n.name, is_global=is_global) 1701 location = not expr and self.get_access_location(name) or None 1702 1703 # Mark any local assignments as volatile in exception blocks. 1704 1705 if expr and self.in_function and not is_global and self.in_try_except: 1706 self.make_volatile(n.name) 1707 1708 # Set the replacement target for local objects. 1709 # Note that this will not apply to all local objects, with only floats 1710 # supporting replaceable values. 1711 1712 if expr and self.in_function and not is_global: 1713 self.result_target_name = encode_path(n.name) 1714 1715 # Expression processing is deferred until after any result target has 1716 # been set. 1717 1718 if process_expr: 1719 expr = self.process_structure_node(expr) 1720 1721 # Qualified names are used for resolved static references or for 1722 # static namespace members. The reference should be configured to return 1723 # such names. 1724 1725 name_ref = TrResolvedNameRef(n.name, ref, expr=expr, is_global=is_global, 1726 location=location) 1727 return not expr and self.get_aliases(name_ref) or name_ref 1728 1729 def get_aliases(self, name_ref): 1730 1731 "Return alias references for the given 'name_ref'." 1732 1733 location = name_ref.access_location() 1734 accessor_locations = self.deducer.access_index.get(location) 1735 1736 if not accessor_locations: 1737 return None 1738 1739 refs = set() 1740 1741 for accessor_location in accessor_locations: 1742 alias_refs = self.deducer.referenced_objects.get(accessor_location) 1743 if alias_refs: 1744 refs.update(alias_refs) 1745 1746 if refs: 1747 return AliasResult(name_ref, refs, location) 1748 else: 1749 return None 1750 1751 def make_volatile(self, name): 1752 1753 "Record 'name' as volatile in the current namespace." 1754 1755 self.volatile_locals.add(name) 1756 1757 def process_not_node(self, n): 1758 1759 "Process the given operator node 'n'." 1760 1761 return self.make_negation(self.process_structure_node(n.expr)) 1762 1763 def process_raise_node(self, n): 1764 1765 "Process the given raise node 'n'." 1766 1767 # NOTE: Determine which raise statement variants should be permitted. 1768 1769 if n.expr1: 1770 1771 # Names with accompanying arguments are treated like invocations. 1772 1773 if n.expr2: 1774 call = compiler.ast.CallFunc(n.expr1, [n.expr2]) 1775 exc = self.process_structure_node(call) 1776 self.writestmt("__Raise(%s);" % exc) 1777 1778 # Raise instances, testing the kind at run-time if necessary and 1779 # instantiating any non-instance. 1780 1781 else: 1782 exc = self.process_structure_node(n.expr1) 1783 1784 if isinstance(exc, TrInstanceRef): 1785 self.writestmt("__Raise(%s);" % exc) 1786 else: 1787 self.writestmt("__Raise(__ensure_instance(%s));" % exc) 1788 else: 1789 self.writestmt("__Throw(__tmp_exc);") 1790 1791 def process_return_node(self, n): 1792 1793 "Process the given return node 'n'." 1794 1795 if self.in_function: 1796 self.result_target_name = "__result" 1797 1798 expr = self.process_structure_node(n.value) or PredefinedConstantRef("None") 1799 1800 if self.in_try_finally or self.in_try_except: 1801 self.writestmt("__Return(%s);" % expr) 1802 else: 1803 self.writestmt("return %s;" % expr) 1804 1805 return ReturnRef() 1806 1807 def process_try_node(self, n): 1808 1809 """ 1810 Process the given "try...except" node 'n'. 1811 """ 1812 1813 in_try_except = self.in_try_except 1814 self.in_try_except = True 1815 1816 # Use macros to implement exception handling. 1817 1818 self.writestmt("__Try") 1819 self.writeline("{") 1820 self.indent += 1 1821 self.process_structure_node(n.body) 1822 1823 # Put the else statement in another try block that handles any raised 1824 # exceptions and converts them to exceptions that will not be handled by 1825 # the main handling block. 1826 1827 if n.else_: 1828 self.writestmt("__Try") 1829 self.writeline("{") 1830 self.indent += 1 1831 self.process_structure_node(n.else_) 1832 self.indent -= 1 1833 self.writeline("}") 1834 self.writeline("__Catch (__tmp_exc)") 1835 self.writeline("{") 1836 self.indent += 1 1837 self.writeline("if (__tmp_exc.raising) __RaiseElse(__tmp_exc.arg);") 1838 self.writeline("else if (__tmp_exc.completing) __Throw(__tmp_exc);") 1839 self.indent -= 1 1840 self.writeline("}") 1841 1842 # Complete the try block and enter the finally block, if appropriate. 1843 1844 if self.in_try_finally: 1845 self.writestmt("__Complete;") 1846 1847 self.indent -= 1 1848 self.writeline("}") 1849 1850 self.in_try_except = in_try_except 1851 1852 # Handlers are tests within a common handler block. 1853 1854 self.writeline("__Catch (__tmp_exc)") 1855 self.writeline("{") 1856 self.indent += 1 1857 1858 # Introduce an if statement to handle the completion of a try block. 1859 1860 self.process_try_completion() 1861 1862 # Handle exceptions in else blocks converted to __RaiseElse, converting 1863 # them back to normal exceptions. 1864 1865 if n.else_: 1866 self.writeline("else if (__tmp_exc.raising_else) __Raise(__tmp_exc.arg);") 1867 1868 # Exception handling. 1869 1870 for name, var, handler in n.handlers: 1871 1872 # Test for specific exceptions. 1873 1874 if name is not None: 1875 name_ref = self.process_structure_node(name) 1876 self.writeline("else if (__ISINSTANCE(__tmp_exc.arg, %s))" % name_ref) 1877 else: 1878 self.writeline("else if (1)") 1879 1880 self.writeline("{") 1881 self.indent += 1 1882 1883 # Establish the local for the handler. 1884 1885 if var is not None: 1886 self.writestmt("%s;" % self.process_name_node(var, make_expression("__tmp_exc.arg"))) 1887 1888 if handler is not None: 1889 self.process_structure_node(handler) 1890 1891 self.indent -= 1 1892 self.writeline("}") 1893 1894 # Re-raise unhandled exceptions. 1895 1896 self.writeline("else __Throw(__tmp_exc);") 1897 1898 # End the handler block. 1899 1900 self.indent -= 1 1901 self.writeline("}") 1902 print >>self.out 1903 1904 def process_try_finally_node(self, n): 1905 1906 """ 1907 Process the given "try...finally" node 'n'. 1908 """ 1909 1910 in_try_finally = self.in_try_finally 1911 self.in_try_finally = True 1912 1913 # Use macros to implement exception handling. 1914 1915 self.writestmt("__Try") 1916 self.writeline("{") 1917 self.indent += 1 1918 self.process_structure_node(n.body) 1919 self.indent -= 1 1920 self.writeline("}") 1921 1922 self.in_try_finally = in_try_finally 1923 1924 # Finally clauses handle special exceptions. 1925 1926 self.writeline("__Catch (__tmp_exc)") 1927 self.writeline("{") 1928 self.indent += 1 1929 self.process_structure_node(n.final) 1930 1931 # Introduce an if statement to handle the completion of a try block. 1932 1933 self.process_try_completion() 1934 self.writeline("else __Throw(__tmp_exc);") 1935 1936 self.indent -= 1 1937 self.writeline("}") 1938 print >>self.out 1939 1940 def process_try_completion(self): 1941 1942 "Generate a test for the completion of a try block." 1943 1944 self.writestmt("if (__tmp_exc.completing)") 1945 self.writeline("{") 1946 self.indent += 1 1947 1948 # Do not return anything at the module level. 1949 1950 if self.get_namespace_path() != self.name: 1951 1952 # Only use the normal return statement if no surrounding try blocks 1953 # apply. 1954 1955 if not self.in_try_finally and not self.in_try_except: 1956 self.writeline("if (!__ISNULL(__tmp_exc.arg)) return __tmp_exc.arg;") 1957 else: 1958 self.writeline("if (!__ISNULL(__tmp_exc.arg)) __Throw(__tmp_exc);") 1959 1960 self.indent -= 1 1961 self.writeline("}") 1962 1963 def process_while_node(self, n): 1964 1965 "Process the given while node 'n'." 1966 1967 self.writeline("while (1)") 1968 self.writeline("{") 1969 self.indent += 1 1970 test = self.process_structure_node(n.test) 1971 1972 # Emit the loop termination condition unless "while <true value>" is 1973 # indicated. 1974 1975 if not (isinstance(test, PredefinedConstantRef) and test.value): 1976 1977 # Emit a negated test of the continuation condition. 1978 1979 self.start_if(True, self.make_negation(test)) 1980 if n.else_: 1981 self.process_structure_node(n.else_) 1982 self.writestmt("break;") 1983 self.end_if() 1984 1985 in_conditional = self.in_conditional 1986 self.in_conditional = True 1987 self.process_structure_node(n.body) 1988 self.in_conditional = in_conditional 1989 1990 self.indent -= 1 1991 self.writeline("}") 1992 print >>self.out 1993 1994 # Special variable usage. 1995 1996 def get_temp_path(self): 1997 1998 """ 1999 Return the appropriate namespace path for temporary names in the current 2000 namespace. 2001 """ 2002 2003 if self.in_function: 2004 return self.get_namespace_path() 2005 else: 2006 return self.name 2007 2008 def record_temp(self, name): 2009 2010 """ 2011 Record the use of the temporary 'name' in the current namespace. At the 2012 class or module level, the temporary name is associated with the module, 2013 since the variable will then be allocated in the module's own main 2014 program. 2015 """ 2016 2017 path = self.get_temp_path() 2018 2019 init_item(self.temp_usage, path, list) 2020 self.temp_usage[path].append(name) 2021 2022 def remove_temps(self, names): 2023 2024 """ 2025 Remove 'names' from temporary storage allocations, each instance 2026 removing each request for storage. 2027 """ 2028 2029 path = self.get_temp_path() 2030 2031 for name in names: 2032 if self.uses_temp(path, name): 2033 self.temp_usage[path].remove(name) 2034 2035 def uses_temp(self, path, name): 2036 2037 """ 2038 Return whether the given namespace 'path' employs a temporary variable 2039 with the given 'name'. Note that 'path' should only be a module or a 2040 function or method, not a class. 2041 """ 2042 2043 return self.temp_usage.has_key(path) and name in self.temp_usage[path] 2044 2045 def make_negation(self, expr): 2046 2047 "Return a negated form of 'expr'." 2048 2049 result = NegationResult(expr) 2050 2051 # Negation discards the temporary results of its operand. 2052 2053 temps = expr.discards_temporary() 2054 if temps: 2055 self.remove_temps(temps) 2056 2057 return result 2058 2059 # Output generation. 2060 2061 def start_output(self): 2062 2063 "Write the declarations at the top of each source file." 2064 2065 print >>self.out, """\ 2066 #include "types.h" 2067 #include "exceptions.h" 2068 #include "ops.h" 2069 #include "progconsts.h" 2070 #include "progops.h" 2071 #include "progtypes.h" 2072 #include "main.h" 2073 """ 2074 2075 def start_unit(self): 2076 2077 "Record output within a generated function for later use." 2078 2079 self.out = StringIO() 2080 2081 def end_unit(self): 2082 2083 "Restore the output stream." 2084 2085 out = self.out 2086 self.out = self.out_toplevel 2087 return out 2088 2089 def flush_unit(self, name, out): 2090 2091 "Add declarations and generated code." 2092 2093 self.write_temporaries(name) 2094 print >>self.out 2095 out.seek(0) 2096 self.out.write(out.read()) 2097 2098 def start_module(self): 2099 2100 "Write the start of each module's main function." 2101 2102 print >>self.out, "void __main_%s()" % encode_path(self.name) 2103 print >>self.out, "{" 2104 self.indent += 1 2105 2106 # Define temporary variables, excluded from the module structure itself. 2107 2108 tempnames = [] 2109 2110 for n in self.importer.all_module_attrs[self.name]: 2111 if n.startswith("$t"): 2112 tempnames.append(encode_path(n)) 2113 2114 if tempnames: 2115 tempnames.sort() 2116 self.writeline("__attr %s;" % ", ".join(tempnames)) 2117 2118 self.start_unit() 2119 2120 def end_module(self): 2121 2122 "End each module by closing its main function." 2123 2124 out = self.end_unit() 2125 self.flush_unit(self.name, out) 2126 2127 self.indent -= 1 2128 print >>self.out, "}" 2129 2130 def start_function(self, name): 2131 2132 "Start the function having the given 'name'." 2133 2134 self.indent += 1 2135 2136 self.start_unit() 2137 2138 def end_function(self, name): 2139 2140 "End the function having the given 'name'." 2141 2142 out = self.end_unit() 2143 2144 # Write the signature at the top indentation level. 2145 2146 self.indent -= 1 2147 self.write_parameters(name) 2148 print >>self.out, "{" 2149 2150 # Obtain local names from parameters. 2151 2152 parameters = self.importer.function_parameters[name] 2153 locals = self.importer.function_locals[name].keys() 2154 names = [] 2155 volatile_names = [] 2156 2157 for n in locals: 2158 2159 # Filter out special names and parameters. Note that self is a local 2160 # regardless of whether it originally appeared in the parameters or 2161 # not. 2162 2163 if n.startswith("$l") or n in parameters or n == "self": 2164 continue 2165 if n in self.volatile_locals: 2166 volatile_names.append(encode_path(n)) 2167 else: 2168 names.append(encode_path(n)) 2169 2170 # Emit required local names at the function indentation level. 2171 2172 self.indent += 1 2173 2174 if names: 2175 names.sort() 2176 self.writeline("__attr %s;" % ", ".join(names)) 2177 2178 if volatile_names: 2179 volatile_names.sort() 2180 self.writeline("volatile __attr %s;" % ", ".join(volatile_names)) 2181 2182 self.flush_unit(name, out) 2183 2184 self.indent -= 1 2185 print >>self.out, "}" 2186 print >>self.out 2187 2188 def write_parameters(self, name): 2189 2190 """ 2191 For the function having the given 'name', write definitions of 2192 parameters found in the arguments array. 2193 """ 2194 2195 # Generate any self reference. 2196 2197 l = [] 2198 l.append("__attr __result") 2199 2200 if self.is_method(name): 2201 l.append("__attr self") 2202 else: 2203 l.append("__attr __self") 2204 2205 # Generate aliases for the parameters. 2206 2207 for parameter in self.importer.function_parameters[name]: 2208 l.append("%s__attr %s" % ( 2209 parameter in self.volatile_locals and "volatile " or "", 2210 encode_path(parameter))) 2211 2212 self.writeline("__attr %s(%s)" % ( 2213 encode_function_pointer(name), ", ".join(l))) 2214 2215 def write_temporaries(self, name): 2216 2217 "Write temporary storage employed by 'name'." 2218 2219 # Provide space for the recorded number of temporary variables. 2220 2221 if self.uses_temp(name, "__tmp_targets"): 2222 self.writeline("__attr __tmp_targets[%d];" % self.max_function_target) 2223 2224 if self.uses_temp(name, "__tmp_contexts"): 2225 self.writeline("__attr __tmp_contexts[%d];" % self.max_context_index) 2226 2227 if self.uses_temp(name, "__tmp_values"): 2228 self.writeline("__attr __tmp_values[%d];" % self.max_accessor_index) 2229 2230 # Add temporary variable usage details. 2231 2232 if self.uses_temp(name, "__tmp_results"): 2233 self.writeline("__attr __tmp_results[%d] = {0};" % self.max_result_target) 2234 2235 if self.uses_temp(name, "__tmp_private_context"): 2236 self.writeline("__attr __tmp_private_context;") 2237 if self.uses_temp(name, "__tmp_target_value"): 2238 self.writeline("__attr __tmp_target_value;") 2239 if self.uses_temp(name, "__tmp_result"): 2240 self.writeline("__attr __tmp_result;") 2241 2242 module = self.importer.get_module(self.name) 2243 2244 if name in module.exception_namespaces: 2245 self.writeline("__exc __tmp_exc;") 2246 2247 def start_if(self, first, test_ref): 2248 statement = "%sif" % (not first and "else " or "") 2249 2250 # Consume logical results directly. 2251 2252 if isinstance(test_ref, LogicalResult): 2253 self.writeline("%s %s" % (statement, test_ref.apply_test())) 2254 temps = test_ref.discards_temporary() 2255 if temps: 2256 self.remove_temps(temps) 2257 else: 2258 self.writeline("%s (__BOOL(%s))" % (statement, test_ref)) 2259 2260 self.writeline("{") 2261 self.indent += 1 2262 2263 def end_if(self): 2264 self.indent -= 1 2265 self.writeline("}") 2266 2267 def start_else(self): 2268 self.writeline("else") 2269 self.writeline("{") 2270 self.indent += 1 2271 2272 def end_else(self): 2273 self.indent -= 1 2274 self.writeline("}") 2275 2276 def statement(self, expr): 2277 s = str(expr) 2278 if s: 2279 self.writestmt("%s;" % s) 2280 2281 def statements(self, results): 2282 for result in results: 2283 self.statement(result) 2284 2285 def writeline(self, s): 2286 print >>self.out, "%s%s" % (self.pad(), self.indenttext(s, self.indent + 1)) 2287 2288 def writestmt(self, s): 2289 self.writeline(s) 2290 2291 def write_comment(self, s): 2292 self.writestmt("/* %s */" % s) 2293 2294 def pad(self, extra=0): 2295 return (self.indent + extra) * self.tabstop 2296 2297 def indenttext(self, s, levels): 2298 lines = s.split("\n") 2299 out = [lines[0]] 2300 for line in lines[1:]: 2301 out.append(levels * self.tabstop + line) 2302 if line.endswith("("): 2303 levels += 1 2304 elif line.startswith(")"): 2305 levels -= 1 2306 return "\n".join(out) 2307 2308 # vim: tabstop=4 expandtab shiftwidth=4