1 #!/usr/bin/env python 2 3 """ 4 Translate programs. 5 6 Copyright (C) 2015, 2016, 2017, 2018, 2024 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, self.process_structure_node(expr)) 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 temps = set() 611 612 for sub in substituted: 613 if self.temp_subs.has_key(sub): 614 temps.add(self.temp_subs[sub]) 615 616 for temp in temps: 617 self.next_temp(temp) 618 619 # Get full final identity details. 620 621 if final_identity and not refs: 622 refs = set([self.importer.identify(final_identity)]) 623 624 del self.attrs[0] 625 return AttrResult(output, refs, location, 626 context_identity, context_identity_verified, 627 accessor_test, accessor_stored) 628 629 def init_substitutions(self): 630 631 """ 632 Initialise substitutions, defining temporary variable mappings, some of 633 which are also used as substitutions, together with operation mappings 634 used as substitutions in instructions defined by the optimiser. 635 """ 636 637 self.temp_subs = { 638 639 # Substitutions used by instructions. 640 641 "<private_context>" : "__tmp_private_context", 642 "<target_accessor>" : "__tmp_target_value", 643 644 # Mappings to be replaced by those given below. 645 646 "<accessor>" : "__tmp_values", 647 "<context>" : "__tmp_contexts", 648 "<test_context_revert>" : "__tmp_contexts", 649 "<test_context_static>" : "__tmp_contexts", 650 "<set_context>" : "__tmp_contexts", 651 "<set_private_context>" : "__tmp_private_context", 652 "<set_accessor>" : "__tmp_values", 653 "<set_target_accessor>" : "__tmp_target_value", 654 } 655 656 self.op_subs = { 657 "<accessor>" : "__get_accessor", 658 "<context>" : "__get_context", 659 "<test_context_revert>" : "__test_context_revert", 660 "<test_context_static>" : "__test_context_static", 661 "<set_context>" : "__set_context", 662 "<set_private_context>" : "__set_private_context", 663 "<set_accessor>" : "__set_accessor", 664 "<set_target_accessor>" : "__set_target_accessor", 665 } 666 667 def get_referenced_attributes(self, location): 668 669 """ 670 Convert 'location' to the form used by the deducer and retrieve any 671 identified attributes. 672 """ 673 674 # Determine whether any deduced references refer to the accessed 675 # attribute. 676 677 attrnames = location.attrnames 678 attrnames = attrnames and attrnames.split(".") 679 remaining = attrnames and len(attrnames) > 1 680 681 access_location = self.deducer.const_accesses.get(location) 682 683 if remaining and not access_location: 684 return set() 685 686 return self.deducer.get_references_for_access(access_location or location) 687 688 def get_referenced_attribute_invocations(self, location): 689 690 """ 691 Convert 'location' to the form used by the deducer and retrieve any 692 identified attribute invocation details. 693 """ 694 695 access_location = self.deducer.const_accesses.get(location) 696 return self.deducer.reference_invocations_unsuitable.get(access_location or location) 697 698 def get_accessor_kinds(self, location): 699 700 "Return the accessor kinds for 'location'." 701 702 return self.deducer.accessor_kinds.get(location) 703 704 def get_access_location(self, name, attrnames=None): 705 706 """ 707 Using the current namespace, the given 'name', and the 'attrnames' 708 employed in an access, return the access location. 709 """ 710 711 path = self.get_path_for_access() 712 713 # Get the location used by the deducer and optimiser and find any 714 # recorded access. 715 716 attrnames = attrnames and ".".join(self.attrs) 717 access_number = self.get_access_number(path, name, attrnames) 718 self.update_access_number(path, name, attrnames) 719 return AccessLocation(path, name, attrnames, access_number) 720 721 def get_access_number(self, path, name, attrnames): 722 access = name, attrnames 723 if self.attr_accesses.has_key(path) and self.attr_accesses[path].has_key(access): 724 return self.attr_accesses[path][access] 725 else: 726 return 0 727 728 def update_access_number(self, path, name, attrnames): 729 access = name, attrnames 730 if name: 731 init_item(self.attr_accesses, path, dict) 732 init_item(self.attr_accesses[path], access, lambda: 0) 733 self.attr_accesses[path][access] += 1 734 735 def get_accessor_location(self, name): 736 737 """ 738 Using the current namespace and the given 'name', return the accessor 739 location. 740 """ 741 742 path = self.get_path_for_access() 743 744 # Get the location used by the deducer and optimiser and find any 745 # recorded accessor. 746 747 version = self.get_accessor_number(path, name) 748 self.update_accessor_number(path, name) 749 return Location(path, name, None, version) 750 751 def get_accessor_number(self, path, name): 752 if self.attr_accessors.has_key(path) and self.attr_accessors[path].has_key(name): 753 return self.attr_accessors[path][name] 754 else: 755 return 0 756 757 def update_accessor_number(self, path, name): 758 if name: 759 init_item(self.attr_accessors, path, dict) 760 init_item(self.attr_accessors[path], name, lambda: 0) 761 self.attr_accessors[path][name] += 1 762 763 def process_class_node(self, n): 764 765 "Process the given class node 'n'." 766 767 class_name = self.get_object_path(n.name) 768 769 # Where a class is set conditionally or where the name may refer to 770 # different values, assign the name. 771 772 ref = self.importer.identify(class_name) 773 774 if not ref.static(): 775 self.process_assignment_for_object(n.name, 776 make_expression("__ATTRVALUE(&%s)" % encode_path(class_name))) 777 778 self.enter_namespace(n.name) 779 780 if self.have_object(): 781 self.write_comment("Class: %s" % class_name) 782 783 self.initialise_inherited_members(class_name) 784 785 self.process_structure(n) 786 self.write_comment("End class: %s" % class_name) 787 788 self.exit_namespace() 789 790 def initialise_inherited_members(self, class_name): 791 792 "Initialise members of 'class_name' inherited from its ancestors." 793 794 for name, path in self.importer.all_class_attrs[class_name].items(): 795 target = "%s.%s" % (class_name, name) 796 797 # Ignore attributes with definitions. 798 799 ref = self.importer.identify(target) 800 if ref: 801 continue 802 803 # Ignore special type attributes. 804 805 if is_type_attribute(name): 806 continue 807 808 # Reference inherited attributes. 809 810 ref = self.importer.identify(path) 811 if ref and not ref.static(): 812 parent, attrname = path.rsplit(".", 1) 813 814 self.writestmt("__store_via_object(&%s, %s, __load_via_object(&%s, %s));" % ( 815 encode_path(class_name), name, 816 encode_path(parent), attrname 817 )) 818 819 def process_from_node(self, n): 820 821 "Process the given node 'n', importing from another module." 822 823 path = self.get_namespace_path() 824 825 # Attempt to obtain the referenced objects. 826 827 for name, alias in n.names: 828 if name == "*": 829 raise InspectError("Only explicitly specified names can be imported from modules.", path, n) 830 831 # Obtain the path of the assigned name. 832 833 objpath = self.get_object_path(alias or name) 834 835 # Obtain the identity of the name. 836 837 ref = self.importer.identify(objpath) 838 839 # Where the name is not static, assign the value. 840 841 if ref and not ref.static() and ref.get_name(): 842 self.writestmt("%s;" % 843 TrResolvedNameRef(alias or name, Reference("<var>", None, objpath), 844 expr=TrResolvedNameRef(name, ref))) 845 846 def process_function_body_node(self, n): 847 848 """ 849 Process the given function, lambda, if expression or list comprehension 850 node 'n', generating the body. 851 """ 852 853 function_name = self.get_namespace_path() 854 self.start_function(function_name) 855 856 # Process the function body. 857 858 in_conditional = self.in_conditional 859 self.in_conditional = False 860 self.function_target = 0 861 self.max_function_target = 0 862 self.context_index = 0 863 self.max_context_index = 0 864 self.accessor_index = 0 865 self.max_accessor_index = 0 866 867 # Volatile locals for exception handling. 868 869 self.volatile_locals = set() 870 871 # Process any guards defined for the parameters. 872 873 for name in self.importer.function_parameters.get(function_name): 874 self.generate_guard(name) 875 876 # Also support self in methods, since some mix-in methods may only work 877 # with certain descendant classes. 878 879 if self.in_method(): 880 self.generate_guard("self") 881 882 # Make assignments for .name entries in the parameters, provided this is 883 # a method. 884 885 if self.in_method(): 886 for name in self.importer.function_attr_initialisers.get(function_name) or []: 887 self.process_assignment_node( 888 compiler.ast.AssAttr(compiler.ast.Name("self"), name, "OP_ASSIGN"), 889 compiler.ast.Name(name)) 890 891 # Produce the body and any additional return statement. 892 893 expr = self.process_statement_node(n.code) or \ 894 self.in_method() and \ 895 function_name.rsplit(".", 1)[-1] == "__init__" and \ 896 TrResolvedNameRef("self", self.importer.function_locals[function_name]["self"]) or \ 897 PredefinedConstantRef("None") 898 899 if not isinstance(expr, ReturnRef): 900 self.writestmt("return %s;" % expr) 901 902 self.in_conditional = in_conditional 903 904 self.end_function(function_name) 905 906 def generate_guard(self, name): 907 908 """ 909 Get the accessor details for 'name', found in the current namespace, and 910 generate any guards defined for it. 911 """ 912 913 # Obtain the location, keeping track of assignment versions. 914 915 location = self.get_accessor_location(name) 916 test = self.deducer.accessor_guard_tests.get(location) 917 918 # Generate any guard from the deduced information. 919 920 if test: 921 guard, guard_type = test 922 923 if guard == "specific": 924 ref = first(self.deducer.accessor_all_types[location]) 925 argstr = "&%s" % encode_path(ref.get_origin()) 926 elif guard == "common": 927 ref = first(self.deducer.accessor_all_general_types[location]) 928 argstr = encode_path(encode_type_attribute(ref.get_origin())) 929 else: 930 return 931 932 # Write a test that raises a TypeError upon failure. 933 934 self.writestmt("if (!__test_%s_%s(__VALUE(%s), %s)) __raise_type_error();" % ( 935 guard, guard_type, encode_path(name), argstr)) 936 937 def process_function_node(self, n): 938 939 """ 940 Process the given function, lambda, if expression or list comprehension 941 node 'n', generating any initialisation statements. 942 """ 943 944 # Where a function is declared conditionally, use a separate name for 945 # the definition, and assign the definition to the stated name. 946 947 original_name = n.name 948 949 if self.in_conditional or self.in_function: 950 name = self.get_lambda_name() 951 else: 952 name = n.name 953 954 objpath = self.get_object_path(name) 955 956 # Obtain details of the defaults. 957 958 defaults = self.process_function_defaults(n, name, objpath) 959 if defaults: 960 for default in defaults: 961 self.writeline("%s;" % default) 962 963 # Where a function is set conditionally or where the name may refer to 964 # different values, assign the name. 965 966 ref = self.importer.identify(objpath) 967 968 if self.in_conditional or self.in_function: 969 self.process_assignment_for_object(original_name, compiler.ast.Name(name)) 970 elif not ref.static(): 971 context = self.is_method(objpath) 972 973 self.process_assignment_for_object(original_name, 974 make_expression("__ATTRVALUE(&%s)" % encode_path(objpath))) 975 976 def process_function_defaults(self, n, name, objpath, instance_name=None): 977 978 """ 979 Process the given function or lambda node 'n', initialising defaults 980 that are dynamically set. The given 'name' indicates the name of the 981 function. The given 'objpath' indicates the origin of the function. 982 The given 'instance_name' indicates the name of any separate instance 983 of the function created to hold the defaults. 984 985 Return a list of operations setting defaults on a function instance. 986 """ 987 988 function_name = self.get_object_path(name) 989 function_defaults = self.importer.function_defaults.get(function_name) 990 if not function_defaults: 991 return None 992 993 # Determine whether any unidentified defaults are involved. 994 995 for argname, default in function_defaults: 996 if not default.static(): 997 break 998 else: 999 return None 1000 1001 # Handle bound methods. 1002 1003 if not instance_name: 1004 instance_name = "&%s" % encode_path(objpath) 1005 else: 1006 instance_name = "__VALUE(%s)" % instance_name 1007 1008 # Where defaults are involved but cannot be identified, obtain a new 1009 # instance of the lambda and populate the defaults. 1010 1011 defaults = [] 1012 1013 # Join the original defaults with the inspected defaults. 1014 1015 original_defaults = [(argname, default) for (argname, default) in compiler.ast.get_defaults(n) if default] 1016 1017 for i, (original, inspected) in enumerate(map(None, original_defaults, function_defaults)): 1018 1019 # Obtain any reference for the default. 1020 1021 if original: 1022 argname, default = original 1023 name_ref = self.process_structure_node(default) 1024 elif inspected: 1025 argname, default = inspected 1026 name_ref = TrResolvedNameRef(argname, default) 1027 else: 1028 continue 1029 1030 # Generate default initialisers except when constants are employed. 1031 # Constants should be used when populating the function structures. 1032 1033 if name_ref and not isinstance(name_ref, TrConstantValueRef): 1034 defaults.append("__SETDEFAULT(%s, %s, %s)" % (instance_name, i, name_ref)) 1035 1036 return defaults 1037 1038 def process_if_node(self, n): 1039 1040 """ 1041 Process the given "if" node 'n'. 1042 """ 1043 1044 first = True 1045 for test, body in n.tests: 1046 test_ref = self.process_statement_node(test) 1047 self.start_if(first, test_ref) 1048 1049 in_conditional = self.in_conditional 1050 self.in_conditional = True 1051 self.process_statement_node(body) 1052 self.in_conditional = in_conditional 1053 1054 self.end_if() 1055 first = False 1056 1057 if n.else_: 1058 self.start_else() 1059 self.process_statement_node(n.else_) 1060 self.end_else() 1061 1062 print >>self.out 1063 1064 def process_invocation_node(self, n): 1065 1066 "Process the given invocation node 'n'." 1067 1068 # Process the expression. 1069 1070 expr = self.process_structure_node(n.node) 1071 1072 # Obtain details of the invocation expression. 1073 1074 objpath = expr.get_origin() 1075 location = expr.access_location() 1076 refs = expr.references() 1077 1078 # Identified target details. 1079 1080 target = None 1081 target_structure = None 1082 1083 # Specific function target information. 1084 1085 function = None 1086 1087 # Instantiation involvement. 1088 1089 instantiation = False 1090 literal_instantiation = False 1091 1092 # Invocation requirements. 1093 1094 context_required = True 1095 have_access_context = isinstance(expr, AttrResult) 1096 1097 # The context identity is merely the thing providing the context. 1098 # A verified context is one that does not need further testing for 1099 # suitability. 1100 1101 context_identity = have_access_context and expr.context() 1102 context_verified = have_access_context and expr.context_verified() 1103 1104 # The presence of any test operations in the accessor expression. 1105 # With such operations present, the expression cannot be eliminated. 1106 1107 tests_accessor = have_access_context and expr.tests_accessor() 1108 stores_accessor = have_access_context and expr.stores_accessor() 1109 1110 # Parameter details and parameter list dimensions. 1111 1112 parameters = None 1113 num_parameters = None 1114 num_defaults = None 1115 1116 # Obtain details of the callable and of its parameters. 1117 1118 # Literals may be instantiated specially. 1119 1120 if expr.is_name() and expr.name.startswith("$L") and objpath: 1121 instantiation = literal_instantiation = expr 1122 target = encode_literal_instantiator(objpath) 1123 context_required = False 1124 1125 # Identified targets employ function pointers directly. 1126 1127 elif objpath: 1128 parameters = self.importer.function_parameters.get(objpath) 1129 function_defaults = self.importer.function_defaults.get(objpath) 1130 num_parameters = parameters and len(parameters) or 0 1131 num_defaults = function_defaults and len(function_defaults) or 0 1132 1133 # Class invocation involves instantiators. 1134 1135 if expr.has_kind("<class>"): 1136 instantiation = expr 1137 target = encode_instantiator_pointer(objpath) 1138 init_ref = self.importer.all_class_attrs[objpath]["__init__"] 1139 target_structure = "&%s" % encode_path(init_ref) 1140 context_required = False 1141 1142 # Only plain functions and bound methods employ function pointers. 1143 1144 elif expr.has_kind("<function>"): 1145 function = objpath 1146 1147 # Test for functions and methods. 1148 1149 context_required = self.is_method(objpath) 1150 1151 accessor_kinds = location and self.get_accessor_kinds(location) 1152 1153 instance_accessor = accessor_kinds and \ 1154 len(accessor_kinds) == 1 and \ 1155 first(accessor_kinds) == "<instance>" 1156 1157 # Only identify certain bound methods or functions. 1158 1159 if not context_required or instance_accessor: 1160 target = encode_function_pointer(objpath) 1161 1162 # Access bound method defaults even if it is not clear whether 1163 # the accessor is appropriate. 1164 1165 target_structure = "&%s" % encode_path(objpath) 1166 1167 # Other targets are retrieved at run-time. 1168 1169 else: 1170 if location: 1171 attrnames = location.attrnames 1172 attrname = attrnames and attrnames.rsplit(".", 1)[-1] 1173 1174 # Determine common aspects of any identifiable targets. 1175 1176 if attrname or refs: 1177 all_params = set() 1178 all_defaults = set() 1179 min_params = set() 1180 max_params = set() 1181 1182 # Employ references from the expression or find all 1183 # possible attributes for the given attribute name. 1184 1185 refs = refs or self.get_attributes_for_attrname(attrname) 1186 1187 # Obtain parameters and defaults for each possible target. 1188 1189 for ref in refs: 1190 origin = ref.get_origin() 1191 params = self.importer.function_parameters.get(origin) 1192 1193 defaults = self.importer.function_defaults.get(origin) 1194 if defaults is not None: 1195 all_defaults.add(tuple(defaults)) 1196 1197 if params is not None: 1198 all_params.add(tuple(params)) 1199 min_params.add(len(params) - (defaults and len(defaults) or 0)) 1200 max_params.add(len(params)) 1201 else: 1202 refs = set() 1203 break 1204 1205 # Where the parameters and defaults are always the same, 1206 # permit populating them in advance. 1207 1208 if refs: 1209 if self.uses_keyword_arguments(n): 1210 if len(all_params) == 1 and (not all_defaults or len(all_defaults) == 1): 1211 parameters = first(all_params) 1212 function_defaults = all_defaults and first(all_defaults) or [] 1213 num_parameters = parameters and len(parameters) or 0 1214 num_defaults = function_defaults and len(function_defaults) or 0 1215 else: 1216 if len(min_params) == 1 and len(max_params) == 1: 1217 num_parameters = first(max_params) 1218 num_defaults = first(max_params) - first(min_params) 1219 1220 # Some information about the target may be available and be used to 1221 # provide warnings about argument compatibility. 1222 1223 if self.importer.give_warning("args"): 1224 unsuitable = self.get_referenced_attribute_invocations(location) 1225 1226 if unsuitable: 1227 for ref in unsuitable: 1228 _objpath = ref.get_origin() 1229 print >>sys.stderr, \ 1230 "In %s, at line %d, inappropriate number of " \ 1231 "arguments given. Need %d arguments to call %s." % ( 1232 self.get_namespace_path(), n.lineno, 1233 len(self.importer.function_parameters[_objpath]), 1234 _objpath) 1235 1236 # Logical statement about available parameter information. 1237 1238 known_parameters = num_parameters is not None 1239 1240 # The source of context information: target or temporary. 1241 1242 need_context_target = context_required and not have_access_context 1243 1244 need_context_stored = context_required and context_identity and \ 1245 context_identity.startswith("__get_context") 1246 1247 # Determine any readily-accessible target identity. 1248 1249 target_named = expr.is_name() and str(expr) or None 1250 target_identity = target or target_named 1251 1252 # Use of target information to populate defaults. 1253 1254 defaults_target_var = not (parameters and function_defaults is not None) and \ 1255 known_parameters and len(n.args) < num_parameters 1256 1257 # Use of a temporary target variable in these situations: 1258 # 1259 # A target provided by an expression needed for defaults. 1260 # 1261 # A target providing the context but not using a name to do so. 1262 # 1263 # A target expression involving the definition of a context which may 1264 # then be evaluated and stored to ensure that the context is available 1265 # during argument evaluation. 1266 # 1267 # An expression featuring an accessor test. 1268 1269 need_target_stored = defaults_target_var and not target_identity or \ 1270 need_context_target and not target_identity or \ 1271 need_context_stored or \ 1272 tests_accessor and not target 1273 1274 # Define stored target details. 1275 1276 target_stored = "__tmp_targets[%d]" % self.function_target 1277 target_var = need_target_stored and target_stored or target_identity 1278 1279 if need_target_stored: 1280 self.record_temp("__tmp_targets") 1281 1282 if need_context_stored: 1283 self.record_temp("__tmp_contexts") 1284 1285 if stores_accessor: 1286 self.record_temp("__tmp_values") 1287 1288 # NOTE: Special case for optimisation. 1289 1290 yields_integer = target and objpath == "native.int.is_int" 1291 1292 # Arguments are presented in a temporary frame array with any context 1293 # always being the first argument. Where it would be unused, it may be 1294 # set to null. 1295 1296 if context_required: 1297 if have_access_context: 1298 context_arg = context_identity 1299 else: 1300 context_arg = "__CONTEXT_AS_VALUE(%s)" % target_var 1301 else: 1302 context_arg = "__NULL" 1303 1304 args = [context_arg] 1305 reserved_args = 1 1306 1307 # Complete the array with null values, permitting tests for a complete 1308 # set of arguments. 1309 1310 args += [None] * (num_parameters is None and len(n.args) or num_parameters is not None and num_parameters or 0) 1311 kwcodes = [] 1312 kwargs = [] 1313 1314 # Any invocations in the arguments will store target details in a 1315 # different location. 1316 1317 function_target = self.function_target 1318 context_index = self.context_index 1319 accessor_index = self.accessor_index 1320 1321 if need_target_stored: 1322 self.next_target() 1323 1324 if need_context_stored: 1325 self.next_context() 1326 1327 if stores_accessor: 1328 self.next_accessor() 1329 1330 in_parameter_list = self.in_parameter_list 1331 self.in_parameter_list = True 1332 1333 for i, arg in enumerate(n.args): 1334 argexpr = self.process_structure_node(arg) 1335 1336 # Store a keyword argument, either in the argument list or 1337 # in a separate keyword argument list for subsequent lookup. 1338 1339 if isinstance(arg, compiler.ast.Keyword): 1340 1341 # With knowledge of the target, store the keyword 1342 # argument directly. 1343 1344 if parameters: 1345 try: 1346 argnum = parameters.index(arg.name) 1347 except ValueError: 1348 raise TranslateError("Argument %s is not recognised." % arg.name, 1349 self.get_namespace_path(), n) 1350 args[argnum + reserved_args] = str(argexpr) 1351 1352 # Otherwise, store the details in a separate collection. 1353 1354 else: 1355 kwargs.append(str(argexpr)) 1356 kwcodes.append("{%s, %s}" % ( 1357 encode_ppos(arg.name), encode_pcode(arg.name))) 1358 1359 # Store non-keyword arguments in the argument list, rejecting 1360 # superfluous arguments. 1361 1362 else: 1363 try: 1364 args[i + reserved_args] = str(argexpr) 1365 except IndexError: 1366 raise TranslateError("Too many arguments specified.", 1367 self.get_namespace_path(), n) 1368 1369 # Reference the current target again. 1370 1371 self.in_parameter_list = in_parameter_list 1372 1373 if not self.in_parameter_list: 1374 self.function_target = function_target 1375 self.context_index = context_index 1376 self.accessor_index = accessor_index 1377 1378 # Defaults are added to the frame where arguments are missing. 1379 1380 if parameters and function_defaults is not None: 1381 1382 # Visit each default and set any missing arguments. Where keyword 1383 # arguments have been used, the defaults must be inspected and, if 1384 # necessary, inserted into gaps in the argument list. 1385 1386 for i, (argname, default) in enumerate(function_defaults): 1387 argnum = parameters.index(argname) 1388 if not args[argnum + reserved_args]: 1389 args[argnum + reserved_args] = "__GETDEFAULT(%s, %d)" % (target_structure, i) 1390 1391 elif known_parameters: 1392 1393 # No specific parameter details are provided, but no keyword 1394 # arguments are used. Thus, defaults can be supplied using position 1395 # information only. 1396 1397 i = len(n.args) 1398 pos = i - (num_parameters - num_defaults) 1399 while i < num_parameters: 1400 args[i + reserved_args] = "__GETDEFAULT(%s.value, %d)" % (target_var, pos) 1401 i += 1 1402 pos += 1 1403 1404 # Test for missing arguments. 1405 1406 if None in args: 1407 raise TranslateError("Not all arguments supplied.", 1408 self.get_namespace_path(), n) 1409 1410 # Encode the arguments. 1411 1412 # Where literal instantiation is occurring, add an argument indicating 1413 # the number of values. The context is excluded. 1414 1415 if literal_instantiation: 1416 final_args = args[reserved_args:] 1417 argstr = "%d, %s" % (len(final_args), ", ".join(final_args)) 1418 else: 1419 # NOTE: Special case for optimisation. 1420 1421 if yields_integer: 1422 final_args = args[reserved_args:] 1423 else: 1424 final_args = args 1425 1426 argstr = ", ".join(final_args) 1427 1428 kwargstr = kwargs and ("__ARGS(%s)" % ", ".join(kwargs)) or "0" 1429 kwcodestr = kwcodes and ("__KWARGS(%s)" % ", ".join(kwcodes)) or "0" 1430 1431 # First, the invocation expression is presented. 1432 1433 stages = [] 1434 emit = stages.append 1435 1436 # Assign and yield any stored target. 1437 # The context may be set in the expression. 1438 1439 if need_target_stored: 1440 emit("%s = %s" % (target_var, expr)) 1441 target_expr = target_var 1442 1443 # Otherwise, retain the expression for later use. 1444 1445 else: 1446 target_expr = str(expr) 1447 1448 # Any specific callable is then obtained for invocation. 1449 1450 if target: 1451 1452 # An expression involving a test of the accessor providing the target. 1453 # This must be emitted in order to perform the test. 1454 1455 if tests_accessor: 1456 emit(str(expr)) 1457 1458 emit(target) 1459 1460 # Methods accessed via unidentified accessors are obtained for 1461 # invocation. 1462 1463 elif function: 1464 if context_required: 1465 1466 # Avoid further context testing if appropriate. 1467 1468 if have_access_context and context_verified: 1469 emit("__get_function_member(%s)" % target_expr) 1470 1471 # Otherwise, test the context for the function/method. 1472 1473 else: 1474 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1475 else: 1476 emit("_get_function_member(%s)" % target_expr) 1477 1478 # With known parameters, the target can be tested. 1479 1480 elif known_parameters: 1481 if self.always_callable(refs): 1482 if context_verified: 1483 emit("__get_function_member(%s)" % target_expr) 1484 else: 1485 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1486 else: 1487 emit("__check_and_get_function(%s, %s)" % (context_arg, target_expr)) 1488 1489 # With a known target, the function is obtained directly and called. 1490 # By putting the invocation at the end of the final element in the 1491 # instruction sequence (the stages), the result becomes the result of 1492 # the sequence. Moreover, the parameters become part of the sequence 1493 # and thereby participate in a guaranteed evaluation order. 1494 1495 if target or function or known_parameters: 1496 stages[-1] += "(%s)" % argstr 1497 if instantiation: 1498 return InstantiationResult(instantiation, stages) 1499 else: 1500 # Provide the parameter details for possible optimisation when 1501 # translating the result. 1502 1503 return InvocationResult(stages, 1504 yields_integer and final_args or None) 1505 1506 # With unknown targets, the generic invocation function is applied to 1507 # the callable and argument collections. 1508 1509 else: 1510 emit("__invoke(\n%s,\n%d, %d, %s, %s,\n%d, %s\n)" % ( 1511 target_expr, 1512 self.always_callable(refs) and 1 or 0, 1513 len(kwargs), kwcodestr, kwargstr, 1514 len(args), "__ARGS(%s)" % argstr)) 1515 return InvocationResult(stages) 1516 1517 def next_temp(self, name): 1518 1519 "Allocate the next temporary storage element for 'name'." 1520 1521 if name == "__tmp_targets": 1522 self.next_target() 1523 elif name == "__tmp_contexts": 1524 self.next_context() 1525 elif name == "__tmp_values": 1526 self.next_accessor() 1527 elif name in ("__tmp_private_context", "__tmp_target_value", "__tmp_result"): 1528 pass 1529 else: 1530 raise TranslateError("Temporary storage %s is not recognised." % name, 1531 self.get_namespace_path()) 1532 1533 self.record_temp(name) 1534 1535 def next_target(self): 1536 1537 "Allocate the next function target storage." 1538 1539 self.function_target += 1 1540 self.max_function_target = max(self.function_target, self.max_function_target) 1541 1542 def next_context(self): 1543 1544 "Allocate the next context value storage." 1545 1546 self.context_index += 1 1547 self.max_context_index = max(self.context_index, self.max_context_index) 1548 1549 def next_accessor(self): 1550 1551 "Allocate the next accessor value storage." 1552 1553 self.accessor_index += 1 1554 self.max_accessor_index = max(self.accessor_index, self.max_accessor_index) 1555 1556 def always_callable(self, refs): 1557 1558 "Determine whether all 'refs' are callable." 1559 1560 if not refs: 1561 return False 1562 1563 for ref in refs: 1564 if not ref.has_kind("<function>") and not self.importer.get_attributes(ref, "__fn__"): 1565 return False 1566 1567 return True 1568 1569 def need_default_arguments(self, objpath, nargs): 1570 1571 """ 1572 Return whether any default arguments are needed when invoking the object 1573 given by 'objpath'. 1574 """ 1575 1576 parameters = self.importer.function_parameters.get(objpath) 1577 return nargs < len(parameters) 1578 1579 def uses_keyword_arguments(self, n): 1580 1581 "Return whether invocation node 'n' uses keyword arguments." 1582 1583 for arg in enumerate(n.args): 1584 if isinstance(arg, compiler.ast.Keyword): 1585 return True 1586 1587 return False 1588 1589 def get_attributes_for_attrname(self, attrname): 1590 1591 "Return a set of all attributes exposed by 'attrname'." 1592 1593 usage = [(attrname, True, False)] 1594 class_types = self.deducer.get_class_types_for_usage(usage) 1595 instance_types = self.deducer.get_instance_types_for_usage(usage) 1596 module_types = self.deducer.get_module_types_for_usage(usage) 1597 attrs = set() 1598 1599 for ref in combine_types(class_types, instance_types, module_types): 1600 attrs.update(self.importer.get_attributes(ref, attrname)) 1601 1602 return attrs 1603 1604 def process_lambda_node(self, n): 1605 1606 "Process the given lambda node 'n'." 1607 1608 name = self.get_lambda_name() 1609 function_name = self.get_object_path(name) 1610 instance_name = "__get_accessor(%d)" % self.accessor_index 1611 1612 defaults = self.process_function_defaults(n, name, function_name, instance_name) 1613 1614 # Without defaults, produce an attribute referring to the function. 1615 1616 if not defaults: 1617 return make_expression("__ATTRVALUE(&%s)" % encode_path(function_name)) 1618 1619 # With defaults, copy the function structure and set the defaults on the 1620 # copy. 1621 1622 else: 1623 self.record_temp("__tmp_values") 1624 accessor_index = self.accessor_index 1625 self.next_accessor() 1626 return make_expression("""\ 1627 (__set_accessor(%d, __ATTRVALUE(__COPY(&%s, sizeof(%s)))), 1628 %s, 1629 __get_accessor(%d))""" % ( 1630 accessor_index, 1631 encode_path(function_name), 1632 encode_symbol("obj", function_name), 1633 ", ".join(defaults), 1634 accessor_index)) 1635 1636 def process_logical_node(self, n): 1637 1638 "Process the given operator node 'n'." 1639 1640 self.record_temp("__tmp_result") 1641 1642 conjunction = isinstance(n, compiler.ast.And) 1643 results = [] 1644 1645 for node in n.nodes: 1646 results.append(self.process_structure_node(node)) 1647 1648 return LogicalOperationResult(results, conjunction) 1649 1650 def process_name_node(self, n, expr=None): 1651 1652 "Process the given name node 'n' with the optional assignment 'expr'." 1653 1654 # Determine whether the name refers to a static external entity. 1655 1656 if n.name in predefined_constants: 1657 return PredefinedConstantRef(n.name, expr) 1658 1659 # Convert literal references, operator function names, and print 1660 # function names to references. 1661 1662 elif n.name.startswith("$L") or n.name.startswith("$op") or \ 1663 n.name.startswith("$seq") or n.name.startswith("$print"): 1664 1665 ref, paths = self.importer.get_module(self.name).special[n.name] 1666 return TrResolvedNameRef(n.name, ref) 1667 1668 # Get the appropriate name for the name reference, using the same method 1669 # as in the inspector. 1670 1671 path = self.get_namespace_path() 1672 objpath = self.get_object_path(n.name) 1673 1674 # Determine any assigned globals. 1675 1676 globals = self.importer.get_module(self.name).scope_globals.get(path) 1677 1678 # Explicitly declared globals. 1679 1680 if globals and n.name in globals: 1681 objpath = self.get_global_path(n.name) 1682 is_global = True 1683 1684 # Implicitly referenced globals in functions. 1685 1686 elif self.in_function: 1687 is_global = n.name not in self.importer.function_locals[path] 1688 1689 # Implicitly referenced globals elsewhere. 1690 1691 else: 1692 namespace = self.importer.identify(path) 1693 is_global = not self.importer.get_attributes(namespace, n.name) 1694 1695 # Get the static identity of the name. 1696 1697 ref = self.importer.identify(objpath) 1698 if ref and not ref.get_name(): 1699 ref = ref.alias(objpath) 1700 1701 # Obtain any resolved names for non-assignment names. 1702 1703 if not expr and not ref and self.in_function: 1704 locals = self.importer.function_locals.get(path) 1705 ref = locals and locals.get(n.name) 1706 1707 # Find any invocation or alias details. 1708 1709 name = self.get_name_for_tracking(n.name, is_global=is_global) 1710 location = not expr and self.get_access_location(name) or None 1711 1712 # Mark any local assignments as volatile in exception blocks. 1713 1714 if expr and self.in_function and not is_global and self.in_try_except: 1715 self.make_volatile(n.name) 1716 1717 # Qualified names are used for resolved static references or for 1718 # static namespace members. The reference should be configured to return 1719 # such names. 1720 1721 name_ref = TrResolvedNameRef(n.name, ref, expr=expr, is_global=is_global, 1722 location=location) 1723 return not expr and self.get_aliases(name_ref) or name_ref 1724 1725 def get_aliases(self, name_ref): 1726 1727 "Return alias references for the given 'name_ref'." 1728 1729 location = name_ref.access_location() 1730 accessor_locations = self.deducer.access_index.get(location) 1731 1732 if not accessor_locations: 1733 return None 1734 1735 refs = set() 1736 1737 for accessor_location in accessor_locations: 1738 alias_refs = self.deducer.referenced_objects.get(accessor_location) 1739 if alias_refs: 1740 refs.update(alias_refs) 1741 1742 if refs: 1743 return AliasResult(name_ref, refs, location) 1744 else: 1745 return None 1746 1747 def make_volatile(self, name): 1748 1749 "Record 'name' as volatile in the current namespace." 1750 1751 self.volatile_locals.add(name) 1752 1753 def process_not_node(self, n): 1754 1755 "Process the given operator node 'n'." 1756 1757 return self.make_negation(self.process_structure_node(n.expr)) 1758 1759 def process_raise_node(self, n): 1760 1761 "Process the given raise node 'n'." 1762 1763 # NOTE: Determine which raise statement variants should be permitted. 1764 1765 if n.expr1: 1766 1767 # Names with accompanying arguments are treated like invocations. 1768 1769 if n.expr2: 1770 call = compiler.ast.CallFunc(n.expr1, [n.expr2]) 1771 exc = self.process_structure_node(call) 1772 self.writestmt("__Raise(%s);" % exc) 1773 1774 # Raise instances, testing the kind at run-time if necessary and 1775 # instantiating any non-instance. 1776 1777 else: 1778 exc = self.process_structure_node(n.expr1) 1779 1780 if isinstance(exc, TrInstanceRef) or exc.is_well_defined_instance(): 1781 self.writestmt("__Raise(%s);" % exc) 1782 else: 1783 self.writestmt("__Raise(__ensure_instance(%s));" % exc) 1784 else: 1785 self.writestmt("__Throw(__tmp_exc);") 1786 1787 def process_return_node(self, n): 1788 1789 "Process the given return node 'n'." 1790 1791 expr = self.process_structure_node(n.value) or PredefinedConstantRef("None") 1792 if self.in_try_finally or self.in_try_except: 1793 self.writestmt("__Return(%s);" % expr) 1794 else: 1795 self.writestmt("return %s;" % expr) 1796 1797 return ReturnRef() 1798 1799 def process_try_node(self, n): 1800 1801 """ 1802 Process the given "try...except" node 'n'. 1803 """ 1804 1805 in_try_except = self.in_try_except 1806 self.in_try_except = True 1807 1808 # Use macros to implement exception handling. 1809 1810 self.writestmt("__Try") 1811 self.writeline("{") 1812 self.indent += 1 1813 self.process_statement_node(n.body) 1814 1815 # Put the else statement in another try block that handles any raised 1816 # exceptions and converts them to exceptions that will not be handled by 1817 # the main handling block. 1818 1819 if n.else_: 1820 self.writestmt("__Try") 1821 self.writeline("{") 1822 self.indent += 1 1823 self.process_statement_node(n.else_) 1824 self.indent -= 1 1825 self.writeline("}") 1826 self.writeline("__Catch (__tmp_exc)") 1827 self.writeline("{") 1828 self.indent += 1 1829 self.writeline("if (__tmp_exc.raising) __RaiseElse(__tmp_exc.arg);") 1830 self.writeline("else if (__tmp_exc.completing) __Throw(__tmp_exc);") 1831 self.indent -= 1 1832 self.writeline("}") 1833 1834 # Complete the try block and enter the finally block, if appropriate. 1835 1836 if self.in_try_finally: 1837 self.writestmt("__Complete;") 1838 1839 self.indent -= 1 1840 self.writeline("}") 1841 1842 self.in_try_except = in_try_except 1843 1844 # Handlers are tests within a common handler block. 1845 1846 self.writeline("__Catch (__tmp_exc)") 1847 self.writeline("{") 1848 self.indent += 1 1849 1850 # Introduce an if statement to handle the completion of a try block. 1851 1852 self.process_try_completion() 1853 1854 # Handle exceptions in else blocks converted to __RaiseElse, converting 1855 # them back to normal exceptions. 1856 1857 if n.else_: 1858 self.writeline("else if (__tmp_exc.raising_else) __Raise(__tmp_exc.arg);") 1859 1860 # Exception handling. 1861 1862 for name, var, handler in n.handlers: 1863 1864 # Test for specific exceptions. 1865 1866 if name is not None: 1867 name_ref = self.process_statement_node(name) 1868 self.writeline("else if (__ISINSTANCE(__tmp_exc.arg, %s))" % name_ref) 1869 else: 1870 self.writeline("else if (1)") 1871 1872 self.writeline("{") 1873 self.indent += 1 1874 1875 # Establish the local for the handler. 1876 1877 if var is not None: 1878 self.writestmt("%s;" % self.process_name_node(var, make_expression("__tmp_exc.arg"))) 1879 1880 if handler is not None: 1881 self.process_statement_node(handler) 1882 1883 self.indent -= 1 1884 self.writeline("}") 1885 1886 # Re-raise unhandled exceptions. 1887 1888 self.writeline("else __Throw(__tmp_exc);") 1889 1890 # End the handler block. 1891 1892 self.indent -= 1 1893 self.writeline("}") 1894 print >>self.out 1895 1896 def process_try_finally_node(self, n): 1897 1898 """ 1899 Process the given "try...finally" node 'n'. 1900 """ 1901 1902 in_try_finally = self.in_try_finally 1903 self.in_try_finally = True 1904 1905 # Use macros to implement exception handling. 1906 1907 self.writestmt("__Try") 1908 self.writeline("{") 1909 self.indent += 1 1910 self.process_statement_node(n.body) 1911 self.indent -= 1 1912 self.writeline("}") 1913 1914 self.in_try_finally = in_try_finally 1915 1916 # Finally clauses handle special exceptions. 1917 1918 self.writeline("__Catch (__tmp_exc)") 1919 self.writeline("{") 1920 self.indent += 1 1921 self.process_statement_node(n.final) 1922 1923 # Introduce an if statement to handle the completion of a try block. 1924 1925 self.process_try_completion() 1926 self.writeline("else __Throw(__tmp_exc);") 1927 1928 self.indent -= 1 1929 self.writeline("}") 1930 print >>self.out 1931 1932 def process_try_completion(self): 1933 1934 "Generate a test for the completion of a try block." 1935 1936 self.writestmt("if (__tmp_exc.completing)") 1937 self.writeline("{") 1938 self.indent += 1 1939 1940 # Do not return anything at the module level. 1941 1942 if self.get_namespace_path() != self.name: 1943 1944 # Only use the normal return statement if no surrounding try blocks 1945 # apply. 1946 1947 if not self.in_try_finally and not self.in_try_except: 1948 self.writeline("if (!__ISNULL(__tmp_exc.arg)) return __tmp_exc.arg;") 1949 else: 1950 self.writeline("if (!__ISNULL(__tmp_exc.arg)) __Throw(__tmp_exc);") 1951 1952 self.indent -= 1 1953 self.writeline("}") 1954 1955 def process_while_node(self, n): 1956 1957 "Process the given while node 'n'." 1958 1959 self.writeline("while (1)") 1960 self.writeline("{") 1961 self.indent += 1 1962 test = self.process_statement_node(n.test) 1963 1964 # Emit the loop termination condition unless "while <true value>" is 1965 # indicated. 1966 1967 if not (isinstance(test, PredefinedConstantRef) and test.value): 1968 1969 # Emit a negated test of the continuation condition. 1970 1971 self.start_if(True, self.make_negation(test)) 1972 if n.else_: 1973 self.process_statement_node(n.else_) 1974 self.writestmt("break;") 1975 self.end_if() 1976 1977 in_conditional = self.in_conditional 1978 self.in_conditional = True 1979 self.process_statement_node(n.body) 1980 self.in_conditional = in_conditional 1981 1982 self.indent -= 1 1983 self.writeline("}") 1984 print >>self.out 1985 1986 # Special variable usage. 1987 1988 def get_temp_path(self): 1989 1990 """ 1991 Return the appropriate namespace path for temporary names in the current 1992 namespace. 1993 """ 1994 1995 if self.in_function: 1996 return self.get_namespace_path() 1997 else: 1998 return self.name 1999 2000 def record_temp(self, name): 2001 2002 """ 2003 Record the use of the temporary 'name' in the current namespace. At the 2004 class or module level, the temporary name is associated with the module, 2005 since the variable will then be allocated in the module's own main 2006 program. 2007 """ 2008 2009 path = self.get_temp_path() 2010 2011 init_item(self.temp_usage, path, list) 2012 self.temp_usage[path].append(name) 2013 2014 def remove_temps(self, names): 2015 2016 """ 2017 Remove 'names' from temporary storage allocations, each instance 2018 removing each request for storage. 2019 """ 2020 2021 path = self.get_temp_path() 2022 2023 for name in names: 2024 if self.uses_temp(path, name): 2025 self.temp_usage[path].remove(name) 2026 2027 def uses_temp(self, path, name): 2028 2029 """ 2030 Return whether the given namespace 'path' employs a temporary variable 2031 with the given 'name'. Note that 'path' should only be a module or a 2032 function or method, not a class. 2033 """ 2034 2035 return self.temp_usage.has_key(path) and name in self.temp_usage[path] 2036 2037 def make_negation(self, expr): 2038 2039 "Return a negated form of 'expr'." 2040 2041 result = NegationResult(expr) 2042 2043 # Negation discards the temporary results of its operand. 2044 2045 temps = expr.discards_temporary() 2046 if temps: 2047 self.remove_temps(temps) 2048 2049 return result 2050 2051 # Output generation. 2052 2053 def start_output(self): 2054 2055 "Write the declarations at the top of each source file." 2056 2057 print >>self.out, """\ 2058 #include "types.h" 2059 #include "exceptions.h" 2060 #include "ops.h" 2061 #include "progconsts.h" 2062 #include "progops.h" 2063 #include "progtypes.h" 2064 #include "main.h" 2065 """ 2066 2067 def start_unit(self): 2068 2069 "Record output within a generated function for later use." 2070 2071 self.out = StringIO() 2072 2073 def end_unit(self): 2074 2075 "Restore the output stream." 2076 2077 out = self.out 2078 self.out = self.out_toplevel 2079 return out 2080 2081 def flush_unit(self, name, out): 2082 2083 "Add declarations and generated code." 2084 2085 self.write_temporaries(name) 2086 print >>self.out 2087 out.seek(0) 2088 self.out.write(out.read()) 2089 2090 def start_module(self): 2091 2092 "Write the start of each module's main function." 2093 2094 print >>self.out, "void __main_%s()" % encode_path(self.name) 2095 print >>self.out, "{" 2096 self.indent += 1 2097 2098 # Define temporary variables, excluded from the module structure itself. 2099 2100 tempnames = [] 2101 2102 for n in self.importer.all_module_attrs[self.name]: 2103 if n.startswith("$t"): 2104 tempnames.append(encode_path(n)) 2105 2106 if tempnames: 2107 tempnames.sort() 2108 self.writeline("__attr %s;" % ", ".join(tempnames)) 2109 2110 self.start_unit() 2111 2112 def end_module(self): 2113 2114 "End each module by closing its main function." 2115 2116 out = self.end_unit() 2117 self.flush_unit(self.name, out) 2118 2119 self.indent -= 1 2120 print >>self.out, "}" 2121 2122 def start_function(self, name): 2123 2124 "Start the function having the given 'name'." 2125 2126 self.indent += 1 2127 2128 self.start_unit() 2129 2130 def end_function(self, name): 2131 2132 "End the function having the given 'name'." 2133 2134 out = self.end_unit() 2135 2136 # Write the signature at the top indentation level. 2137 2138 self.indent -= 1 2139 self.write_parameters(name) 2140 print >>self.out, "{" 2141 2142 # Obtain local names from parameters. 2143 2144 parameters = self.importer.function_parameters[name] 2145 locals = self.importer.function_locals[name].keys() 2146 names = [] 2147 volatile_names = [] 2148 2149 for n in locals: 2150 2151 # Filter out special names and parameters. Note that self is a local 2152 # regardless of whether it originally appeared in the parameters or 2153 # not. 2154 2155 if n.startswith("$l") or n in parameters or n == "self": 2156 continue 2157 if n in self.volatile_locals: 2158 volatile_names.append(encode_path(n)) 2159 else: 2160 names.append(encode_path(n)) 2161 2162 # Emit required local names at the function indentation level. 2163 2164 self.indent += 1 2165 2166 if names: 2167 names.sort() 2168 self.writeline("__attr %s;" % ", ".join(names)) 2169 2170 if volatile_names: 2171 volatile_names.sort() 2172 self.writeline("volatile __attr %s;" % ", ".join(volatile_names)) 2173 2174 self.flush_unit(name, out) 2175 2176 self.indent -= 1 2177 print >>self.out, "}" 2178 print >>self.out 2179 2180 def write_parameters(self, name): 2181 2182 """ 2183 For the function having the given 'name', write definitions of 2184 parameters found in the arguments array. 2185 """ 2186 2187 # Generate any self reference. 2188 2189 l = [] 2190 2191 if self.is_method(name): 2192 l.append("__attr self") 2193 else: 2194 l.append("__attr __self") 2195 2196 # Generate aliases for the parameters. 2197 2198 for parameter in self.importer.function_parameters[name]: 2199 l.append("%s__attr %s" % ( 2200 parameter in self.volatile_locals and "volatile " or "", 2201 encode_path(parameter))) 2202 2203 self.writeline("__attr %s(%s)" % ( 2204 encode_function_pointer(name), ", ".join(l))) 2205 2206 def write_temporaries(self, name): 2207 2208 "Write temporary storage employed by 'name'." 2209 2210 # Provide space for the recorded number of temporary variables. 2211 2212 if self.uses_temp(name, "__tmp_targets") and self.max_function_target: 2213 self.writeline("__attr __tmp_targets[%d];" % self.max_function_target) 2214 2215 if self.uses_temp(name, "__tmp_contexts") and self.max_context_index: 2216 self.writeline("__attr __tmp_contexts[%d];" % self.max_context_index) 2217 2218 if self.uses_temp(name, "__tmp_values") and self.max_accessor_index: 2219 self.writeline("__attr __tmp_values[%d];" % self.max_accessor_index) 2220 2221 # Add temporary variable usage details. 2222 2223 if self.uses_temp(name, "__tmp_private_context"): 2224 self.writeline("__attr __tmp_private_context;") 2225 if self.uses_temp(name, "__tmp_target_value"): 2226 self.writeline("__attr __tmp_target_value;") 2227 if self.uses_temp(name, "__tmp_result"): 2228 self.writeline("__attr __tmp_result;") 2229 2230 module = self.importer.get_module(self.name) 2231 2232 if name in module.exception_namespaces: 2233 self.writeline("__exc __tmp_exc;") 2234 2235 def start_if(self, first, test_ref): 2236 statement = "%sif" % (not first and "else " or "") 2237 2238 # Consume logical results directly. 2239 2240 if isinstance(test_ref, LogicalResult): 2241 self.writeline("%s %s" % (statement, test_ref.apply_test())) 2242 temps = test_ref.discards_temporary() 2243 if temps: 2244 self.remove_temps(temps) 2245 else: 2246 self.writeline("%s (%s)" % (statement, test_ref.apply_test())) 2247 2248 self.writeline("{") 2249 self.indent += 1 2250 2251 def end_if(self): 2252 self.indent -= 1 2253 self.writeline("}") 2254 2255 def start_else(self): 2256 self.writeline("else") 2257 self.writeline("{") 2258 self.indent += 1 2259 2260 def end_else(self): 2261 self.indent -= 1 2262 self.writeline("}") 2263 2264 def statement(self, expr): 2265 s = str(expr) 2266 if s: 2267 self.writestmt("%s;" % s) 2268 2269 def statements(self, results): 2270 for result in results: 2271 self.statement(result) 2272 2273 def writeline(self, s): 2274 print >>self.out, "%s%s" % (self.pad(), self.indenttext(s, self.indent + 1)) 2275 2276 def writestmt(self, s): 2277 self.writeline(s) 2278 2279 def write_comment(self, s): 2280 self.writestmt("/* %s */" % s) 2281 2282 def pad(self, extra=0): 2283 return (self.indent + extra) * self.tabstop 2284 2285 def indenttext(self, s, levels): 2286 lines = s.split("\n") 2287 out = [lines[0]] 2288 for line in lines[1:]: 2289 out.append(levels * self.tabstop + line) 2290 if line.endswith("("): 2291 levels += 1 2292 elif line.startswith(")"): 2293 levels -= 1 2294 return "\n".join(out) 2295 2296 # vim: tabstop=4 expandtab shiftwidth=4