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.reset_temp_limits() 318 319 self.start_module() 320 self.process_structure(node) 321 self.end_module() 322 323 def process_structure(self, node): 324 325 "Process the given 'node' or result." 326 327 # Handle processing requests on results. 328 329 if isinstance(node, Result): 330 return node 331 332 # Handle processing requests on nodes. 333 334 else: 335 l = CommonModule.process_structure(self, node) 336 337 # Return indications of return statement usage. 338 339 if l and isinstance(l[-1], ReturnRef): 340 return l[-1] 341 else: 342 return None 343 344 def process_statement_node(self, node, is_lambda=False): 345 346 "Process the given statement 'node'." 347 348 self.reset_temp_counters() 349 350 if is_lambda: 351 self.result_target_name = "__result" 352 353 return CommonModule.process_statement_node(self, node) 354 355 def process_structure_node(self, n): 356 357 "Process the individual node 'n'." 358 359 # Plain statements emit their expressions. 360 361 if isinstance(n, compiler.ast.Discard): 362 expr = self.process_structure_node(n.expr) 363 self.statement(expr) 364 365 # Module import declarations. 366 367 elif isinstance(n, compiler.ast.From): 368 self.process_from_node(n) 369 370 # Nodes using operator module functions. 371 372 elif isinstance(n, compiler.ast.Operator): 373 return self.process_operator_node(n) 374 375 elif isinstance(n, compiler.ast.AugAssign): 376 self.process_augassign_node(n) 377 378 elif isinstance(n, compiler.ast.Compare): 379 return self.process_compare_node(n) 380 381 elif isinstance(n, compiler.ast.Slice): 382 return self.process_slice_node(n) 383 384 elif isinstance(n, compiler.ast.Sliceobj): 385 return self.process_sliceobj_node(n) 386 387 elif isinstance(n, compiler.ast.Subscript): 388 return self.process_subscript_node(n) 389 390 # Classes are visited, but may be ignored if inside functions. 391 392 elif isinstance(n, compiler.ast.Class): 393 self.process_class_node(n) 394 395 # Functions within namespaces have any dynamic defaults initialised. 396 397 elif isinstance(n, compiler.ast.Function): 398 self.process_function_node(n) 399 400 # Lambdas are replaced with references to separately-generated 401 # functions. 402 403 elif isinstance(n, compiler.ast.Lambda): 404 return self.process_lambda_node(n) 405 406 # Assignments. 407 408 elif isinstance(n, compiler.ast.Assign): 409 410 # Handle each assignment node. 411 412 for node in n.nodes: 413 self.process_assignment_node(node, n.expr) 414 415 # Accesses. 416 417 elif isinstance(n, compiler.ast.Getattr): 418 return self.process_attribute_access(n) 419 420 # Names. 421 422 elif isinstance(n, compiler.ast.Name): 423 return self.process_name_node(n) 424 425 # Loops and conditionals. 426 427 elif isinstance(n, compiler.ast.For): 428 self.process_for_node(n) 429 430 elif isinstance(n, compiler.ast.While): 431 self.process_while_node(n) 432 433 elif isinstance(n, compiler.ast.If): 434 self.process_if_node(n) 435 436 elif isinstance(n, (compiler.ast.And, compiler.ast.Or)): 437 return self.process_logical_node(n) 438 439 elif isinstance(n, compiler.ast.Not): 440 return self.process_not_node(n) 441 442 # Exception control-flow tracking. 443 444 elif isinstance(n, compiler.ast.TryExcept): 445 self.process_try_node(n) 446 447 elif isinstance(n, compiler.ast.TryFinally): 448 self.process_try_finally_node(n) 449 450 # Control-flow modification statements. 451 452 elif isinstance(n, compiler.ast.Break): 453 self.writestmt("break;") 454 455 elif isinstance(n, compiler.ast.Continue): 456 self.writestmt("continue;") 457 458 elif isinstance(n, compiler.ast.Raise): 459 self.process_raise_node(n) 460 461 elif isinstance(n, compiler.ast.Return): 462 return self.process_return_node(n) 463 464 # Print statements. 465 466 elif isinstance(n, (compiler.ast.Print, compiler.ast.Printnl)): 467 self.statement(self.process_print_node(n)) 468 469 # Invocations. 470 471 elif isinstance(n, compiler.ast.CallFunc): 472 return self.process_invocation_node(n) 473 474 elif isinstance(n, compiler.ast.Keyword): 475 return self.process_structure_node(n.expr) 476 477 # Constant usage. 478 479 elif isinstance(n, compiler.ast.Const): 480 return self.get_literal_instance(n) 481 482 elif isinstance(n, compiler.ast.Dict): 483 return self.get_literal_instance(n, "dict") 484 485 elif isinstance(n, compiler.ast.List): 486 return self.get_literal_instance(n, "list") 487 488 elif isinstance(n, compiler.ast.Tuple): 489 return self.get_literal_instance(n, "tuple") 490 491 # All other nodes are processed depth-first. 492 493 else: 494 return self.process_structure(n) 495 496 def process_assignment_node(self, n, expr): 497 498 "Process the individual node 'n' to be assigned the contents of 'expr'." 499 500 # Names and attributes are assigned the entire expression. 501 502 if isinstance(n, compiler.ast.AssName): 503 name_ref = self.process_name_node(n, expr, True) 504 self.statement(name_ref) 505 506 # Employ guards after assignments if required. 507 508 if expr and name_ref.is_name(): 509 self.generate_guard(name_ref.name) 510 511 elif isinstance(n, compiler.ast.AssAttr): 512 in_assignment = self.in_assignment 513 self.result_target_name = "*__get_attr_ref(%d)" % self.attribute_ref_index 514 self.in_assignment = self.process_structure_node(expr) 515 self.statement(self.process_attribute_access(n)) 516 self.in_assignment = in_assignment 517 518 # Lists and tuples are matched against the expression and their 519 # items assigned to expression items. 520 521 elif isinstance(n, (compiler.ast.AssList, compiler.ast.AssTuple)): 522 self.process_assignment_node_items(n, expr) 523 524 # Slices and subscripts are permitted within assignment nodes. 525 526 elif isinstance(n, compiler.ast.Slice): 527 self.statement(self.process_slice_node(n, expr)) 528 529 elif isinstance(n, compiler.ast.Subscript): 530 self.statement(self.process_subscript_node(n, expr)) 531 532 def process_attribute_access(self, n): 533 534 "Process the given attribute access node 'n'." 535 536 # Obtain any completed chain and return the reference to it. 537 538 attr_expr = self.process_attribute_chain(n) 539 if self.have_access_expression(n): 540 return attr_expr 541 542 # Where the start of the chain of attributes has been reached, process 543 # the complete access. 544 545 name_ref = attr_expr and attr_expr.is_name() and attr_expr 546 name = name_ref and self.get_name_for_tracking(name_ref.name, name_ref) or None 547 548 location = self.get_access_location(name, self.attrs) 549 refs = self.get_referenced_attributes(location) 550 551 # Generate access instructions. 552 553 subs = { 554 "<expr>" : attr_expr, 555 "<name>" : attr_expr, 556 "<assexpr>" : self.in_assignment, 557 } 558 559 subs.update(self.temp_subs) 560 subs.update(self.op_subs) 561 562 output = [] 563 substituted = set() 564 565 # The context set or retrieved will be that used by any enclosing 566 # invocation. 567 568 accessor_index = self.accessor_index 569 attribute_ref_index = self.attribute_ref_index 570 context_index = self.context_index 571 context_identity = None 572 context_identity_verified = False 573 final_identity = None 574 accessor_test = False 575 accessor_stored = False 576 attribute_ref_stored = False 577 578 # Obtain encoded versions of each instruction, accumulating temporary 579 # variables. 580 581 for instruction in self.deducer.access_instructions[location]: 582 583 # Intercept a special instruction identifying the context. 584 585 if instruction[0] in ("<context_identity>", "<context_identity_verified>"): 586 context_identity, _substituted = \ 587 encode_access_instruction_arg(instruction[1], subs, instruction[0], 588 accessor_index, context_index, 589 attribute_ref_index) 590 context_identity_verified = instruction[0] == "<context_identity_verified>" 591 continue 592 593 # Intercept a special instruction identifying the target. The value 594 # is not encoded since it is used internally. 595 596 elif instruction[0] == "<final_identity>": 597 final_identity = instruction[1] 598 continue 599 600 # Modify test instructions. 601 602 elif instruction[0] in typename_ops or instruction[0] in type_ops: 603 instruction = ("__to_error", instruction) 604 accessor_test = True 605 606 # Intercept accessor storage. 607 608 elif instruction[0] == "<set_accessor>": 609 accessor_stored = True 610 611 # Intercept attribute reference storage. 612 613 elif instruction[0] == "<set_attr_ref>": 614 attribute_ref_stored = True 615 self.next_attribute_ref() 616 617 # Collect the encoded instruction, noting any temporary variables 618 # required by it. 619 620 encoded, _substituted = encode_access_instruction(instruction, subs, 621 accessor_index, context_index, 622 attribute_ref_index) 623 output.append(encoded) 624 substituted.update(_substituted) 625 626 # Record temporary name usage. 627 628 for sub in substituted: 629 if self.temp_subs.has_key(sub): 630 self.record_temp(self.temp_subs[sub]) 631 632 # Get full final identity details. 633 634 if final_identity and not refs: 635 refs = set([self.importer.identify(final_identity)]) 636 637 del self.attrs[0] 638 return AttrResult(output, refs, location, 639 context_identity, context_identity_verified, 640 accessor_test, accessor_stored, attribute_ref_stored) 641 642 def init_substitutions(self): 643 644 """ 645 Initialise substitutions, defining temporary variable mappings, some of 646 which are also used as substitutions, together with operation mappings 647 used as substitutions in instructions defined by the optimiser. 648 """ 649 650 self.temp_subs = { 651 652 # Substitutions used by instructions. 653 654 "<private_context>" : "__tmp_private_context", 655 "<target_accessor>" : "__tmp_target_value", 656 657 # Mappings to be replaced by those given below. 658 659 "<accessor>" : "__tmp_values", 660 "<attr_ref>" : "__tmp_attr_refs", 661 "<context>" : "__tmp_contexts", 662 "<test_context_revert>" : "__tmp_contexts", 663 "<test_context_static>" : "__tmp_contexts", 664 "<set_context>" : "__tmp_contexts", 665 "<set_private_context>" : "__tmp_private_context", 666 "<set_accessor>" : "__tmp_values", 667 "<set_attr_ref>" : "__tmp_attr_refs", 668 "<set_target_accessor>" : "__tmp_target_value", 669 } 670 671 self.op_subs = { 672 "<accessor>" : "__get_accessor", 673 "<attr_ref>" : "__get_attr_ref", 674 "<context>" : "__get_context", 675 "<test_context_revert>" : "__test_context_revert", 676 "<test_context_static>" : "__test_context_static", 677 "<set_context>" : "__set_context", 678 "<set_private_context>" : "__set_private_context", 679 "<set_accessor>" : "__set_accessor", 680 "<set_attr_ref>" : "__set_attr_ref", 681 "<set_target_accessor>" : "__set_target_accessor", 682 } 683 684 def get_referenced_attributes(self, location): 685 686 """ 687 Convert 'location' to the form used by the deducer and retrieve any 688 identified attributes. 689 """ 690 691 # Determine whether any deduced references refer to the accessed 692 # attribute. 693 694 attrnames = location.attrnames 695 attrnames = attrnames and attrnames.split(".") 696 remaining = attrnames and len(attrnames) > 1 697 698 access_location = self.deducer.const_accesses.get(location) 699 700 if remaining and not access_location: 701 return set() 702 703 return self.deducer.get_references_for_access(access_location or location) 704 705 def get_referenced_attribute_invocations(self, location): 706 707 """ 708 Convert 'location' to the form used by the deducer and retrieve any 709 identified attribute invocation details. 710 """ 711 712 access_location = self.deducer.const_accesses.get(location) 713 return self.deducer.reference_invocations_unsuitable.get(access_location or location) 714 715 def get_accessor_kinds(self, location): 716 717 "Return the accessor kinds for 'location'." 718 719 return self.deducer.accessor_kinds.get(location) 720 721 def get_access_location(self, name, attrnames=None): 722 723 """ 724 Using the current namespace, the given 'name', and the 'attrnames' 725 employed in an access, return the access location. 726 """ 727 728 path = self.get_path_for_access() 729 730 # Get the location used by the deducer and optimiser and find any 731 # recorded access. 732 733 attrnames = attrnames and ".".join(self.attrs) 734 access_number = self.get_access_number(path, name, attrnames) 735 self.update_access_number(path, name, attrnames) 736 return AccessLocation(path, name, attrnames, access_number) 737 738 def get_access_number(self, path, name, attrnames): 739 access = name, attrnames 740 if self.attr_accesses.has_key(path) and self.attr_accesses[path].has_key(access): 741 return self.attr_accesses[path][access] 742 else: 743 return 0 744 745 def update_access_number(self, path, name, attrnames): 746 access = name, attrnames 747 if name: 748 init_item(self.attr_accesses, path, dict) 749 init_item(self.attr_accesses[path], access, lambda: 0) 750 self.attr_accesses[path][access] += 1 751 752 def get_accessor_location(self, name): 753 754 """ 755 Using the current namespace and the given 'name', return the accessor 756 location. 757 """ 758 759 path = self.get_path_for_access() 760 761 # Get the location used by the deducer and optimiser and find any 762 # recorded accessor. 763 764 version = self.get_accessor_number(path, name) 765 self.update_accessor_number(path, name) 766 return Location(path, name, None, version) 767 768 def get_accessor_number(self, path, name): 769 if self.attr_accessors.has_key(path) and self.attr_accessors[path].has_key(name): 770 return self.attr_accessors[path][name] 771 else: 772 return 0 773 774 def update_accessor_number(self, path, name): 775 if name: 776 init_item(self.attr_accessors, path, dict) 777 init_item(self.attr_accessors[path], name, lambda: 0) 778 self.attr_accessors[path][name] += 1 779 780 def process_class_node(self, n): 781 782 "Process the given class node 'n'." 783 784 class_name = self.get_object_path(n.name) 785 786 # Where a class is set conditionally or where the name may refer to 787 # different values, assign the name. 788 789 ref = self.importer.identify(class_name) 790 791 if not ref.static(): 792 self.process_assignment_for_object(n.name, 793 make_expression("__ATTRVALUE(&%s)" % encode_path(class_name))) 794 795 self.enter_namespace(n.name) 796 797 if self.have_object(): 798 self.write_comment("Class: %s" % class_name) 799 800 self.initialise_inherited_members(class_name) 801 802 self.process_structure(n) 803 self.write_comment("End class: %s" % class_name) 804 805 self.exit_namespace() 806 807 def initialise_inherited_members(self, class_name): 808 809 "Initialise members of 'class_name' inherited from its ancestors." 810 811 for name, path in self.importer.all_class_attrs[class_name].items(): 812 target = "%s.%s" % (class_name, name) 813 814 # Ignore attributes with definitions. 815 816 ref = self.importer.identify(target) 817 if ref: 818 continue 819 820 # Ignore special type attributes. 821 822 if is_type_attribute(name): 823 continue 824 825 # Reference inherited attributes. 826 827 ref = self.importer.identify(path) 828 if ref and not ref.static(): 829 parent, attrname = path.rsplit(".", 1) 830 831 self.writestmt("__store_via_attr_ref(__get_object_attr_ref(&%s, %s), __load_via_object(&%s, %s));" % ( 832 encode_path(class_name), name, 833 encode_path(parent), attrname 834 )) 835 836 def process_from_node(self, n): 837 838 "Process the given node 'n', importing from another module." 839 840 path = self.get_namespace_path() 841 842 # Attempt to obtain the referenced objects. 843 844 for name, alias in n.names: 845 if name == "*": 846 raise InspectError("Only explicitly specified names can be imported from modules.", path, n) 847 848 # Obtain the path of the assigned name. 849 850 objpath = self.get_object_path(alias or name) 851 852 # Obtain the identity of the name. 853 854 ref = self.importer.identify(objpath) 855 856 # Where the name is not static, assign the value. 857 858 if ref and not ref.static() and ref.get_name(): 859 self.writestmt("%s;" % 860 TrResolvedNameRef(alias or name, Reference("<var>", None, objpath), 861 expr=TrResolvedNameRef(name, ref))) 862 863 def process_function_body_node(self, n): 864 865 """ 866 Process the given function, lambda, if expression or list comprehension 867 node 'n', generating the body. 868 """ 869 870 function_name = self.get_namespace_path() 871 self.start_function(function_name) 872 873 # Process the function body. 874 875 in_conditional = self.in_conditional 876 self.in_conditional = False 877 878 # Reset temporary storage counters and limits. 879 880 self.reset_temp_limits() 881 882 # Reset result target storage details. To be effective, storage 883 # locations are not reused between statements. 884 885 self.max_result_target = 0 886 self.result_target = 0 887 888 # Volatile locals for exception handling. 889 890 self.volatile_locals = set() 891 892 # Process any guards defined for the parameters. 893 894 for name in self.importer.function_parameters.get(function_name): 895 self.generate_guard(name) 896 897 # Also support self in methods, since some mix-in methods may only work 898 # with certain descendant classes. 899 900 if self.in_method(): 901 self.generate_guard("self") 902 903 # Make assignments for .name entries in the parameters, provided this is 904 # a method. 905 906 if self.in_method(): 907 for name in self.importer.function_attr_initialisers.get(function_name) or []: 908 909 # Treat each assignment as a separate statement. 910 911 self.reset_temp_counters() 912 913 self.process_assignment_node( 914 compiler.ast.AssAttr(compiler.ast.Name("self"), name, "OP_ASSIGN"), 915 compiler.ast.Name(name)) 916 917 # Produce the body and any additional return statement. 918 919 is_lambda = isinstance(n, compiler.ast.Lambda) 920 921 expr = self.process_statement_node(n.code, is_lambda) or \ 922 self.in_method() and \ 923 function_name.rsplit(".", 1)[-1] == "__init__" and \ 924 TrResolvedNameRef("self", self.importer.function_locals[function_name]["self"]) or \ 925 PredefinedConstantRef("None") 926 927 if not isinstance(expr, ReturnRef): 928 self.writestmt("return %s;" % expr) 929 930 self.in_conditional = in_conditional 931 932 self.end_function(function_name) 933 934 def generate_guard(self, name): 935 936 """ 937 Get the accessor details for 'name', found in the current namespace, and 938 generate any guards defined for it. 939 """ 940 941 # Obtain the location, keeping track of assignment versions. 942 943 location = self.get_accessor_location(name) 944 test = self.deducer.accessor_guard_tests.get(location) 945 946 # Generate any guard from the deduced information. 947 948 if test: 949 guard, guard_type = test 950 951 if guard == "specific": 952 ref = first(self.deducer.accessor_all_types[location]) 953 argstr = "&%s" % encode_path(ref.get_origin()) 954 elif guard == "common": 955 ref = first(self.deducer.accessor_all_general_types[location]) 956 argstr = encode_path(encode_type_attribute(ref.get_origin())) 957 else: 958 return 959 960 # Write a test that raises a TypeError upon failure. 961 962 self.writestmt("if (!__test_%s_%s(__VALUE(%s), %s)) __raise_type_error();" % ( 963 guard, guard_type, encode_path(name), argstr)) 964 965 def process_function_node(self, n): 966 967 """ 968 Process the given function, lambda, if expression or list comprehension 969 node 'n', generating any initialisation statements. 970 """ 971 972 # Where a function is declared conditionally, use a separate name for 973 # the definition, and assign the definition to the stated name. 974 975 original_name = n.name 976 977 if self.in_conditional or self.in_function: 978 name = self.get_lambda_name() 979 else: 980 name = n.name 981 982 objpath = self.get_object_path(name) 983 984 # Obtain details of the defaults. 985 986 defaults = self.process_function_defaults(n, name, objpath) 987 if defaults: 988 for default in defaults: 989 self.writeline("%s;" % default) 990 991 # Where a function is set conditionally or where the name may refer to 992 # different values, assign the name. 993 994 ref = self.importer.identify(objpath) 995 996 if self.in_conditional or self.in_function: 997 self.process_assignment_for_object(original_name, compiler.ast.Name(name)) 998 elif not ref.static(): 999 context = self.is_method(objpath) 1000 1001 self.process_assignment_for_object(original_name, 1002 make_expression("__ATTRVALUE(&%s)" % encode_path(objpath))) 1003 1004 def process_function_defaults(self, n, name, objpath, instance_name=None): 1005 1006 """ 1007 Process the given function or lambda node 'n', initialising defaults 1008 that are dynamically set. The given 'name' indicates the name of the 1009 function. The given 'objpath' indicates the origin of the function. 1010 The given 'instance_name' indicates the name of any separate instance 1011 of the function created to hold the defaults. 1012 1013 Return a list of operations setting defaults on a function instance. 1014 """ 1015 1016 function_name = self.get_object_path(name) 1017 function_defaults = self.importer.function_defaults.get(function_name) 1018 if not function_defaults: 1019 return None 1020 1021 # Determine whether any unidentified defaults are involved. 1022 1023 for argname, default in function_defaults: 1024 if not default.static(): 1025 break 1026 else: 1027 return None 1028 1029 # Handle bound methods. 1030 1031 if not instance_name: 1032 instance_name = "&%s" % encode_path(objpath) 1033 else: 1034 instance_name = "__VALUE(%s)" % instance_name 1035 1036 # Where defaults are involved but cannot be identified, obtain a new 1037 # instance of the lambda and populate the defaults. 1038 1039 defaults = [] 1040 1041 # Join the original defaults with the inspected defaults. 1042 1043 original_defaults = [(argname, default) for (argname, default) in compiler.ast.get_defaults(n) if default] 1044 1045 for i, (original, inspected) in enumerate(map(None, original_defaults, function_defaults)): 1046 1047 # Obtain any reference for the default. 1048 1049 if original: 1050 argname, default = original 1051 name_ref = self.process_structure_node(default) 1052 elif inspected: 1053 argname, default = inspected 1054 name_ref = TrResolvedNameRef(argname, default) 1055 else: 1056 continue 1057 1058 # Generate default initialisers except when constants are employed. 1059 # Constants should be used when populating the function structures. 1060 1061 if name_ref and not isinstance(name_ref, TrConstantValueRef): 1062 defaults.append("__SETDEFAULT(%s, %s, %s)" % (instance_name, i, name_ref)) 1063 1064 return defaults 1065 1066 def process_if_node(self, n): 1067 1068 """ 1069 Process the given "if" node 'n'. 1070 """ 1071 1072 first = True 1073 for test, body in n.tests: 1074 test_ref = self.process_statement_node(test) 1075 self.start_if(first, test_ref) 1076 1077 in_conditional = self.in_conditional 1078 self.in_conditional = True 1079 self.process_statement_node(body) 1080 self.in_conditional = in_conditional 1081 1082 self.end_if() 1083 first = False 1084 1085 if n.else_: 1086 self.start_else() 1087 self.process_statement_node(n.else_) 1088 self.end_else() 1089 1090 print >>self.out 1091 1092 def process_invocation_node(self, n): 1093 1094 "Process the given invocation node 'n'." 1095 1096 # Process the expression. 1097 1098 expr = self.process_structure_node(n.node) 1099 1100 # Obtain details of the invocation expression. 1101 1102 objpath = expr.get_origin() 1103 location = expr.access_location() 1104 refs = expr.references() 1105 1106 # Identified target details. 1107 1108 target = None 1109 target_structure = None 1110 1111 # Specific function target information. 1112 1113 function = None 1114 1115 # Instantiation involvement. 1116 1117 instantiation = False 1118 literal_instantiation = False 1119 1120 # Invocation requirements. 1121 1122 context_required = True 1123 have_access_context = isinstance(expr, AttrResult) 1124 1125 # The context identity is merely the thing providing the context. 1126 # A verified context is one that does not need further testing for 1127 # suitability. 1128 1129 context_identity = have_access_context and expr.context() 1130 context_verified = have_access_context and expr.context_verified() 1131 1132 # The presence of any test operations in the accessor expression. 1133 # With such operations present, the expression cannot be eliminated. 1134 1135 tests_accessor = have_access_context and expr.tests_accessor() 1136 stores_accessor = have_access_context and expr.stores_accessor() 1137 1138 # Parameter details and parameter list dimensions. 1139 1140 parameters = None 1141 num_parameters = None 1142 num_defaults = None 1143 1144 # Obtain details of the callable and of its parameters. 1145 1146 # Literals may be instantiated specially. 1147 1148 if expr.is_name() and expr.name.startswith("$L") and objpath: 1149 instantiation = literal_instantiation = objpath 1150 target = encode_literal_instantiator(objpath) 1151 context_required = False 1152 1153 # Identified targets employ function pointers directly. 1154 1155 elif objpath: 1156 parameters = self.importer.function_parameters.get(objpath) 1157 function_defaults = self.importer.function_defaults.get(objpath) 1158 num_parameters = parameters and len(parameters) or 0 1159 num_defaults = function_defaults and len(function_defaults) or 0 1160 1161 # Class invocation involves instantiators. 1162 1163 if expr.has_kind("<class>"): 1164 instantiation = objpath 1165 target = encode_instantiator_pointer(objpath) 1166 init_ref = self.importer.all_class_attrs[objpath]["__init__"] 1167 target_structure = "&%s" % encode_path(init_ref) 1168 context_required = False 1169 1170 # Only plain functions and bound methods employ function pointers. 1171 1172 elif expr.has_kind("<function>"): 1173 function = objpath 1174 1175 # Test for functions and methods. 1176 1177 context_required = self.is_method(objpath) 1178 1179 accessor_kinds = location and self.get_accessor_kinds(location) 1180 1181 instance_accessor = accessor_kinds and \ 1182 len(accessor_kinds) == 1 and \ 1183 first(accessor_kinds) == "<instance>" 1184 1185 # Only identify certain bound methods or functions. 1186 1187 if not context_required or instance_accessor: 1188 target = encode_function_pointer(objpath) 1189 1190 # Access bound method defaults even if it is not clear whether 1191 # the accessor is appropriate. 1192 1193 target_structure = "&%s" % encode_path(objpath) 1194 1195 # Other targets are retrieved at run-time. 1196 1197 else: 1198 if location: 1199 attrnames = location.attrnames 1200 attrname = attrnames and attrnames.rsplit(".", 1)[-1] 1201 1202 # Determine common aspects of any identifiable targets. 1203 1204 if attrname or refs: 1205 all_params = set() 1206 all_defaults = set() 1207 min_params = set() 1208 max_params = set() 1209 1210 # Employ references from the expression or find all 1211 # possible attributes for the given attribute name. 1212 1213 refs = refs or self.get_attributes_for_attrname(attrname) 1214 1215 # Obtain parameters and defaults for each possible target. 1216 1217 for ref in refs: 1218 origin = ref.get_origin() 1219 params = self.importer.function_parameters.get(origin) 1220 1221 defaults = self.importer.function_defaults.get(origin) 1222 if defaults is not None: 1223 all_defaults.add(tuple(defaults)) 1224 1225 if params is not None: 1226 all_params.add(tuple(params)) 1227 min_params.add(len(params) - (defaults and len(defaults) or 0)) 1228 max_params.add(len(params)) 1229 else: 1230 refs = set() 1231 break 1232 1233 # Where the parameters and defaults are always the same, 1234 # permit populating them in advance. 1235 1236 if refs: 1237 if self.uses_keyword_arguments(n): 1238 if len(all_params) == 1 and (not all_defaults or len(all_defaults) == 1): 1239 parameters = first(all_params) 1240 function_defaults = all_defaults and first(all_defaults) or [] 1241 num_parameters = parameters and len(parameters) or 0 1242 num_defaults = function_defaults and len(function_defaults) or 0 1243 else: 1244 if len(min_params) == 1 and len(max_params) == 1: 1245 num_parameters = first(max_params) 1246 num_defaults = first(max_params) - first(min_params) 1247 1248 # Some information about the target may be available and be used to 1249 # provide warnings about argument compatibility. 1250 1251 if self.importer.give_warning("args"): 1252 unsuitable = self.get_referenced_attribute_invocations(location) 1253 1254 if unsuitable: 1255 for ref in unsuitable: 1256 _objpath = ref.get_origin() 1257 print >>sys.stderr, \ 1258 "In %s, at line %d, inappropriate number of " \ 1259 "arguments given. Need %d arguments to call %s." % ( 1260 self.get_namespace_path(), n.lineno, 1261 len(self.importer.function_parameters[_objpath]), 1262 _objpath) 1263 1264 # Logical statement about available parameter information. 1265 1266 known_parameters = num_parameters is not None 1267 1268 # The source of context information: target or temporary. 1269 1270 need_context_target = context_required and not have_access_context 1271 1272 need_context_stored = context_required and context_identity and \ 1273 context_identity.startswith("__get_context") 1274 1275 # Determine any readily-accessible target identity. 1276 1277 target_named = expr.is_name() and str(expr) or None 1278 target_identity = target or target_named 1279 1280 # Use of target information to populate defaults. 1281 1282 defaults_target_var = not (parameters and function_defaults is not None) and \ 1283 known_parameters and len(n.args) < num_parameters 1284 1285 # Use of a temporary target variable in these situations: 1286 # 1287 # A target provided by an expression needed for defaults. 1288 # 1289 # A target providing the context but not using a name to do so. 1290 # 1291 # A target expression involving the definition of a context which may 1292 # then be evaluated and stored to ensure that the context is available 1293 # during argument evaluation. 1294 # 1295 # An expression featuring an accessor test. 1296 1297 need_target_stored = defaults_target_var and not target_identity or \ 1298 need_context_target and not target_identity or \ 1299 need_context_stored or \ 1300 tests_accessor and not target 1301 1302 # Define stored target details. 1303 1304 target_stored = "__tmp_targets[%d]" % self.function_target 1305 target_var = need_target_stored and target_stored or target_identity 1306 1307 if need_target_stored: 1308 self.record_temp("__tmp_targets") 1309 1310 if need_context_stored: 1311 self.record_temp("__tmp_contexts") 1312 1313 if stores_accessor: 1314 self.record_temp("__tmp_values") 1315 1316 # Employ result targets only in functions. 1317 1318 if self.in_function: 1319 if self.result_target_name: 1320 result_target = self.result_target_name 1321 self.result_target_name = None 1322 else: 1323 result_target = "__tmp_results[%d]" % self.result_target 1324 self.record_temp("__tmp_results") 1325 self.next_result() 1326 else: 1327 result_target = None 1328 1329 # Arguments are presented in a temporary frame array with any context 1330 # always being the first argument. Where it would be unused, it may be 1331 # set to null. 1332 1333 if context_required: 1334 if have_access_context: 1335 context_arg = context_identity 1336 else: 1337 context_arg = "__CONTEXT_AS_VALUE(%s)" % target_var 1338 else: 1339 context_arg = "__NULL" 1340 1341 # Start with result target and context arguments for each invocation. 1342 1343 args = [result_target or "__NULL", context_arg] 1344 reserved_args = 2 1345 1346 # Complete the array with null values, permitting tests for a complete 1347 # set of arguments. 1348 1349 args += [None] * (num_parameters is None and len(n.args) or num_parameters is not None and num_parameters or 0) 1350 kwcodes = [] 1351 kwargs = [] 1352 1353 # Any invocations in the arguments will store target details in a 1354 # different location. 1355 1356 function_target = self.function_target 1357 context_index = self.context_index 1358 accessor_index = self.accessor_index 1359 1360 if need_target_stored: 1361 self.next_target() 1362 1363 if need_context_stored: 1364 self.next_context() 1365 1366 if stores_accessor: 1367 self.next_accessor() 1368 1369 in_parameter_list = self.in_parameter_list 1370 self.in_parameter_list = True 1371 1372 for i, arg in enumerate(n.args): 1373 argexpr = self.process_structure_node(arg) 1374 1375 # Convert any attributes indicating value replacement. 1376 1377 if isinstance(argexpr, InvocationResult) and argexpr.result_target: 1378 argexprstr = "__set_attr(&%s, %s)" % (argexpr.result_target, argexpr) 1379 else: 1380 argexprstr = str(argexpr) 1381 1382 # Store a keyword argument, either in the argument list or 1383 # in a separate keyword argument list for subsequent lookup. 1384 1385 if isinstance(arg, compiler.ast.Keyword): 1386 1387 # With knowledge of the target, store the keyword 1388 # argument directly. 1389 1390 if parameters: 1391 try: 1392 argnum = parameters.index(arg.name) 1393 except ValueError: 1394 raise TranslateError("Argument %s is not recognised." % arg.name, 1395 self.get_namespace_path(), n) 1396 args[argnum + reserved_args] = argexprstr 1397 1398 # Otherwise, store the details in a separate collection. 1399 1400 else: 1401 kwargs.append(argexprstr) 1402 kwcodes.append("{%s, %s}" % ( 1403 encode_ppos(arg.name), encode_pcode(arg.name))) 1404 1405 # Store non-keyword arguments in the argument list, rejecting 1406 # superfluous arguments. 1407 1408 else: 1409 try: 1410 args[i + reserved_args] = argexprstr 1411 except IndexError: 1412 raise TranslateError("Too many arguments specified.", 1413 self.get_namespace_path(), n) 1414 1415 # Reference the current target again. 1416 1417 self.in_parameter_list = in_parameter_list 1418 1419 if not self.in_parameter_list: 1420 self.function_target = function_target 1421 self.context_index = context_index 1422 self.accessor_index = accessor_index 1423 1424 # Defaults are added to the frame where arguments are missing. 1425 1426 if parameters and function_defaults is not None: 1427 1428 # Visit each default and set any missing arguments. Where keyword 1429 # arguments have been used, the defaults must be inspected and, if 1430 # necessary, inserted into gaps in the argument list. 1431 1432 for i, (argname, default) in enumerate(function_defaults): 1433 argnum = parameters.index(argname) 1434 if not args[argnum + reserved_args]: 1435 args[argnum + reserved_args] = "__GETDEFAULT(%s, %d)" % (target_structure, i) 1436 1437 elif known_parameters: 1438 1439 # No specific parameter details are provided, but no keyword 1440 # arguments are used. Thus, defaults can be supplied using position 1441 # information only. 1442 1443 i = len(n.args) 1444 pos = i - (num_parameters - num_defaults) 1445 while i < num_parameters: 1446 args[i + reserved_args] = "__GETDEFAULT(%s.value, %d)" % (target_var, pos) 1447 i += 1 1448 pos += 1 1449 1450 # Test for missing arguments. 1451 1452 if None in args: 1453 raise TranslateError("Not all arguments supplied.", 1454 self.get_namespace_path(), n) 1455 1456 # Encode the arguments. 1457 1458 # Where literal instantiation is occurring, add an argument indicating 1459 # the number of values. The result target and context are excluded. 1460 1461 if literal_instantiation: 1462 argstr = "%d, %s" % (len(args) - reserved_args, ", ".join(args[reserved_args:])) 1463 else: 1464 argstr = ", ".join(args) 1465 1466 kwargstr = kwargs and ("__ARGS(%s)" % ", ".join(kwargs)) or "0" 1467 kwcodestr = kwcodes and ("__KWARGS(%s)" % ", ".join(kwcodes)) or "0" 1468 1469 # First, the invocation expression is presented. 1470 1471 stages = [] 1472 emit = stages.append 1473 1474 # Assign and yield any stored target. 1475 # The context may be set in the expression. 1476 1477 if need_target_stored: 1478 emit("%s = %s" % (target_var, expr)) 1479 target_expr = target_var 1480 1481 # Otherwise, retain the expression for later use. 1482 1483 else: 1484 target_expr = str(expr) 1485 1486 # Any specific callable is then obtained for invocation. 1487 1488 if target: 1489 1490 # An expression involving a test of the accessor providing the target. 1491 # This must be emitted in order to perform the test. 1492 1493 if tests_accessor: 1494 emit(str(expr)) 1495 1496 emit(target) 1497 1498 # Methods accessed via unidentified accessors are obtained for 1499 # invocation. 1500 1501 elif function: 1502 if context_required: 1503 1504 # Avoid further context testing if appropriate. 1505 1506 if have_access_context and context_verified: 1507 emit("__get_function_member(%s)" % target_expr) 1508 1509 # Otherwise, test the context for the function/method. 1510 1511 else: 1512 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1513 else: 1514 emit("_get_function_member(%s)" % target_expr) 1515 1516 # With known parameters, the target can be tested. 1517 1518 elif known_parameters: 1519 if self.always_callable(refs): 1520 if context_verified: 1521 emit("__get_function_member(%s)" % target_expr) 1522 else: 1523 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1524 else: 1525 emit("__check_and_get_function(%s, %s)" % (context_arg, target_expr)) 1526 1527 # With a known target, the function is obtained directly and called. 1528 # By putting the invocation at the end of the final element in the 1529 # instruction sequence (the stages), the result becomes the result of 1530 # the sequence. Moreover, the parameters become part of the sequence 1531 # and thereby participate in a guaranteed evaluation order. 1532 1533 if target or function or known_parameters: 1534 stages[-1] += "(%s)" % argstr 1535 if instantiation: 1536 return InstantiationResult(instantiation, stages) 1537 else: 1538 return InvocationResult(result_target, stages) 1539 1540 # With unknown targets, the generic invocation function is applied to 1541 # the callable and argument collections. 1542 1543 else: 1544 emit("__invoke(\n%s,\n%d, %d, %s, %s,\n%d, %s\n)" % ( 1545 target_expr, 1546 self.always_callable(refs) and 1 or 0, 1547 len(kwargs), kwcodestr, kwargstr, 1548 len(args), "__ARGS(%s)" % argstr)) 1549 return InvocationResult(result_target, stages) 1550 1551 def reset_temp_counters(self): 1552 1553 "Reset the target counters." 1554 1555 self.function_target = 0 1556 self.context_index = 0 1557 self.accessor_index = 0 1558 self.attribute_ref_index = 0 1559 self.result_target_name = None 1560 1561 def reset_temp_limits(self): 1562 1563 "Reset the target counter limits." 1564 1565 self.max_function_target = 0 1566 self.max_context_index = 0 1567 self.max_accessor_index = 0 1568 self.max_attribute_ref_index = 0 1569 1570 def next_result(self): 1571 1572 "Allocate the next result target storage." 1573 1574 self.result_target += 1 1575 self.max_result_target = max(self.result_target, self.max_result_target) 1576 1577 def next_target(self): 1578 1579 "Allocate the next function target storage." 1580 1581 self.function_target += 1 1582 self.max_function_target = max(self.function_target, self.max_function_target) 1583 1584 def next_context(self): 1585 1586 "Allocate the next context value storage." 1587 1588 self.context_index += 1 1589 self.max_context_index = max(self.context_index, self.max_context_index) 1590 1591 def next_accessor(self): 1592 1593 "Allocate the next accessor value storage." 1594 1595 self.accessor_index += 1 1596 self.max_accessor_index = max(self.accessor_index, self.max_accessor_index) 1597 1598 def next_attribute_ref(self): 1599 1600 "Allocate the next attribute reference value storage." 1601 1602 self.attribute_ref_index += 1 1603 self.max_attribute_ref_index = max(self.attribute_ref_index, self.max_attribute_ref_index) 1604 1605 def always_callable(self, refs): 1606 1607 "Determine whether all 'refs' are callable." 1608 1609 if not refs: 1610 return False 1611 1612 for ref in refs: 1613 if not ref.has_kind("<function>") and not self.importer.get_attributes(ref, "__fn__"): 1614 return False 1615 1616 return True 1617 1618 def need_default_arguments(self, objpath, nargs): 1619 1620 """ 1621 Return whether any default arguments are needed when invoking the object 1622 given by 'objpath'. 1623 """ 1624 1625 parameters = self.importer.function_parameters.get(objpath) 1626 return nargs < len(parameters) 1627 1628 def uses_keyword_arguments(self, n): 1629 1630 "Return whether invocation node 'n' uses keyword arguments." 1631 1632 for arg in enumerate(n.args): 1633 if isinstance(arg, compiler.ast.Keyword): 1634 return True 1635 1636 return False 1637 1638 def get_attributes_for_attrname(self, attrname): 1639 1640 "Return a set of all attributes exposed by 'attrname'." 1641 1642 usage = [(attrname, True, False)] 1643 class_types = self.deducer.get_class_types_for_usage(usage) 1644 instance_types = self.deducer.get_instance_types_for_usage(usage) 1645 module_types = self.deducer.get_module_types_for_usage(usage) 1646 attrs = set() 1647 1648 for ref in combine_types(class_types, instance_types, module_types): 1649 attrs.update(self.importer.get_attributes(ref, attrname)) 1650 1651 return attrs 1652 1653 def process_lambda_node(self, n): 1654 1655 "Process the given lambda node 'n'." 1656 1657 name = self.get_lambda_name() 1658 function_name = self.get_object_path(name) 1659 instance_name = "__get_accessor(%d)" % self.accessor_index 1660 1661 defaults = self.process_function_defaults(n, name, function_name, instance_name) 1662 1663 # Without defaults, produce an attribute referring to the function. 1664 1665 if not defaults: 1666 return make_expression("__ATTRVALUE(&%s)" % encode_path(function_name)) 1667 1668 # With defaults, copy the function structure and set the defaults on the 1669 # copy. 1670 1671 else: 1672 self.record_temp("__tmp_values") 1673 return make_expression("""\ 1674 (__set_accessor(%d, __ATTRVALUE(__COPY(&%s, sizeof(%s)))), 1675 %s, 1676 __get_accessor(%d))""" % ( 1677 self.accessor_index, 1678 encode_path(function_name), 1679 encode_symbol("obj", function_name), 1680 ", ".join(defaults), 1681 self.accessor_index)) 1682 1683 def process_logical_node(self, n): 1684 1685 "Process the given operator node 'n'." 1686 1687 self.record_temp("__tmp_result") 1688 1689 conjunction = isinstance(n, compiler.ast.And) 1690 results = [] 1691 1692 for node in n.nodes: 1693 results.append(self.process_structure_node(node)) 1694 1695 return LogicalOperationResult(results, conjunction) 1696 1697 def process_name_node(self, n, expr=None, process_expr=False): 1698 1699 "Process the given name node 'n' with the optional assignment 'expr'." 1700 1701 # Determine whether the name refers to a static external entity. 1702 1703 if n.name in predefined_constants: 1704 return PredefinedConstantRef(n.name, expr) 1705 1706 # Convert literal references, operator function names, and print 1707 # function names to references. 1708 1709 elif n.name.startswith("$L") or n.name.startswith("$op") or \ 1710 n.name.startswith("$seq") or n.name.startswith("$print"): 1711 1712 ref, paths = self.importer.get_module(self.name).special[n.name] 1713 return TrResolvedNameRef(n.name, ref) 1714 1715 # Get the appropriate name for the name reference, using the same method 1716 # as in the inspector. 1717 1718 path = self.get_namespace_path() 1719 objpath = self.get_object_path(n.name) 1720 1721 # Determine any assigned globals. 1722 1723 globals = self.importer.get_module(self.name).scope_globals.get(path) 1724 1725 # Explicitly declared globals. 1726 1727 if globals and n.name in globals: 1728 objpath = self.get_global_path(n.name) 1729 is_global = True 1730 1731 # Implicitly referenced globals in functions. 1732 1733 elif self.in_function: 1734 is_global = n.name not in self.importer.function_locals[path] 1735 1736 # Implicitly referenced globals elsewhere. 1737 1738 else: 1739 namespace = self.importer.identify(path) 1740 is_global = not self.importer.get_attributes(namespace, n.name) 1741 1742 # Get the static identity of the name. 1743 1744 ref = self.importer.identify(objpath) 1745 if ref and not ref.get_name(): 1746 ref = ref.alias(objpath) 1747 1748 # Obtain any resolved names for non-assignment names. 1749 1750 if not expr and not ref and self.in_function: 1751 locals = self.importer.function_locals.get(path) 1752 ref = locals and locals.get(n.name) 1753 1754 # Find any invocation or alias details. 1755 1756 name = self.get_name_for_tracking(n.name, is_global=is_global) 1757 location = not expr and self.get_access_location(name) or None 1758 1759 # Mark any local assignments as volatile in exception blocks. 1760 1761 if expr and self.in_function and not is_global and self.in_try_except: 1762 self.make_volatile(n.name) 1763 1764 # Set the replacement target. Note that this will not apply to all 1765 # objects, with only floats supporting replaceable values. 1766 1767 if expr: 1768 # Prevent parameters from becoming result targets. Otherwise, they 1769 # may inadvertently cause the modification of the supplied object. 1770 1771 parameters = self.importer.function_parameters.get(path) 1772 1773 if not parameters or n.name not in parameters: 1774 target_ref = TrResolvedNameRef(n.name, ref, is_global=is_global, 1775 location=location) 1776 self.result_target_name = str(target_ref) 1777 else: 1778 self.result_target_name = None 1779 1780 # Expression processing is deferred until after any result target has 1781 # been set. 1782 1783 if process_expr: 1784 expr = self.process_structure_node(expr) 1785 1786 # Qualified names are used for resolved static references or for 1787 # static namespace members. The reference should be configured to return 1788 # such names. 1789 1790 name_ref = TrResolvedNameRef(n.name, ref, expr=expr, is_global=is_global, 1791 location=location) 1792 1793 return not expr and self.get_aliases(name_ref) or name_ref 1794 1795 def get_aliases(self, name_ref): 1796 1797 "Return alias references for the given 'name_ref'." 1798 1799 location = name_ref.access_location() 1800 accessor_locations = self.deducer.access_index.get(location) 1801 1802 if not accessor_locations: 1803 return None 1804 1805 refs = set() 1806 1807 for accessor_location in accessor_locations: 1808 alias_refs = self.deducer.referenced_objects.get(accessor_location) 1809 if alias_refs: 1810 refs.update(alias_refs) 1811 1812 if refs: 1813 return AliasResult(name_ref, refs, location) 1814 else: 1815 return None 1816 1817 def make_volatile(self, name): 1818 1819 "Record 'name' as volatile in the current namespace." 1820 1821 self.volatile_locals.add(name) 1822 1823 def process_not_node(self, n): 1824 1825 "Process the given operator node 'n'." 1826 1827 return self.make_negation(self.process_structure_node(n.expr)) 1828 1829 def process_raise_node(self, n): 1830 1831 "Process the given raise node 'n'." 1832 1833 # NOTE: Determine which raise statement variants should be permitted. 1834 1835 if n.expr1: 1836 1837 # Names with accompanying arguments are treated like invocations. 1838 1839 if n.expr2: 1840 call = compiler.ast.CallFunc(n.expr1, [n.expr2]) 1841 exc = self.process_structure_node(call) 1842 self.writestmt("__Raise(%s);" % exc) 1843 1844 # Raise instances, testing the kind at run-time if necessary and 1845 # instantiating any non-instance. 1846 1847 else: 1848 exc = self.process_structure_node(n.expr1) 1849 1850 if isinstance(exc, TrInstanceRef) or exc.is_well_defined_instance(): 1851 self.writestmt("__Raise(%s);" % exc) 1852 else: 1853 self.writestmt("__Raise(__ensure_instance(%s));" % exc) 1854 else: 1855 self.writestmt("__Throw(__tmp_exc);") 1856 1857 def process_return_node(self, n): 1858 1859 "Process the given return node 'n'." 1860 1861 if self.in_function: 1862 self.result_target_name = "__result" 1863 1864 expr = self.process_structure_node(n.value) or PredefinedConstantRef("None") 1865 1866 if self.in_try_finally or self.in_try_except: 1867 self.writestmt("__Return(%s);" % expr) 1868 else: 1869 self.writestmt("return %s;" % expr) 1870 1871 return ReturnRef() 1872 1873 def process_try_node(self, n): 1874 1875 """ 1876 Process the given "try...except" node 'n'. 1877 """ 1878 1879 in_try_except = self.in_try_except 1880 self.in_try_except = True 1881 1882 # Use macros to implement exception handling. 1883 1884 self.writestmt("__Try") 1885 self.writeline("{") 1886 self.indent += 1 1887 self.process_statement_node(n.body) 1888 1889 # Put the else statement in another try block that handles any raised 1890 # exceptions and converts them to exceptions that will not be handled by 1891 # the main handling block. 1892 1893 if n.else_: 1894 self.writestmt("__Try") 1895 self.writeline("{") 1896 self.indent += 1 1897 self.process_statement_node(n.else_) 1898 self.indent -= 1 1899 self.writeline("}") 1900 self.writeline("__Catch (__tmp_exc)") 1901 self.writeline("{") 1902 self.indent += 1 1903 self.writeline("if (__tmp_exc.raising) __RaiseElse(__tmp_exc.arg);") 1904 self.writeline("else if (__tmp_exc.completing) __Throw(__tmp_exc);") 1905 self.indent -= 1 1906 self.writeline("}") 1907 1908 # Complete the try block and enter the finally block, if appropriate. 1909 1910 if self.in_try_finally: 1911 self.writestmt("__Complete;") 1912 1913 self.indent -= 1 1914 self.writeline("}") 1915 1916 self.in_try_except = in_try_except 1917 1918 # Handlers are tests within a common handler block. 1919 1920 self.writeline("__Catch (__tmp_exc)") 1921 self.writeline("{") 1922 self.indent += 1 1923 1924 # Introduce an if statement to handle the completion of a try block. 1925 1926 self.process_try_completion() 1927 1928 # Handle exceptions in else blocks converted to __RaiseElse, converting 1929 # them back to normal exceptions. 1930 1931 if n.else_: 1932 self.writeline("else if (__tmp_exc.raising_else) __Raise(__tmp_exc.arg);") 1933 1934 # Exception handling. 1935 1936 for name, var, handler in n.handlers: 1937 1938 # Test for specific exceptions. 1939 1940 if name is not None: 1941 name_ref = self.process_statement_node(name) 1942 self.writeline("else if (__ISINSTANCE(__tmp_exc.arg, %s))" % name_ref) 1943 else: 1944 self.writeline("else if (1)") 1945 1946 self.writeline("{") 1947 self.indent += 1 1948 1949 # Establish the local for the handler. 1950 1951 if var is not None: 1952 self.writestmt("%s;" % self.process_name_node(var, make_expression("__tmp_exc.arg"))) 1953 1954 if handler is not None: 1955 self.process_statement_node(handler) 1956 1957 self.indent -= 1 1958 self.writeline("}") 1959 1960 # Re-raise unhandled exceptions. 1961 1962 self.writeline("else __Throw(__tmp_exc);") 1963 1964 # End the handler block. 1965 1966 self.indent -= 1 1967 self.writeline("}") 1968 print >>self.out 1969 1970 def process_try_finally_node(self, n): 1971 1972 """ 1973 Process the given "try...finally" node 'n'. 1974 """ 1975 1976 in_try_finally = self.in_try_finally 1977 self.in_try_finally = True 1978 1979 # Use macros to implement exception handling. 1980 1981 self.writestmt("__Try") 1982 self.writeline("{") 1983 self.indent += 1 1984 self.process_statement_node(n.body) 1985 self.indent -= 1 1986 self.writeline("}") 1987 1988 self.in_try_finally = in_try_finally 1989 1990 # Finally clauses handle special exceptions. 1991 1992 self.writeline("__Catch (__tmp_exc)") 1993 self.writeline("{") 1994 self.indent += 1 1995 self.process_statement_node(n.final) 1996 1997 # Introduce an if statement to handle the completion of a try block. 1998 1999 self.process_try_completion() 2000 self.writeline("else __Throw(__tmp_exc);") 2001 2002 self.indent -= 1 2003 self.writeline("}") 2004 print >>self.out 2005 2006 def process_try_completion(self): 2007 2008 "Generate a test for the completion of a try block." 2009 2010 self.writestmt("if (__tmp_exc.completing)") 2011 self.writeline("{") 2012 self.indent += 1 2013 2014 # Do not return anything at the module level. 2015 2016 if self.get_namespace_path() != self.name: 2017 2018 # Only use the normal return statement if no surrounding try blocks 2019 # apply. 2020 2021 if not self.in_try_finally and not self.in_try_except: 2022 self.writeline("if (!__ISNULL(__tmp_exc.arg)) return __tmp_exc.arg;") 2023 else: 2024 self.writeline("if (!__ISNULL(__tmp_exc.arg)) __Throw(__tmp_exc);") 2025 2026 self.indent -= 1 2027 self.writeline("}") 2028 2029 def process_while_node(self, n): 2030 2031 "Process the given while node 'n'." 2032 2033 self.writeline("while (1)") 2034 self.writeline("{") 2035 self.indent += 1 2036 test = self.process_statement_node(n.test) 2037 2038 # Emit the loop termination condition unless "while <true value>" is 2039 # indicated. 2040 2041 if not (isinstance(test, PredefinedConstantRef) and test.value): 2042 2043 # Emit a negated test of the continuation condition. 2044 2045 self.start_if(True, self.make_negation(test)) 2046 if n.else_: 2047 self.process_statement_node(n.else_) 2048 self.writestmt("break;") 2049 self.end_if() 2050 2051 in_conditional = self.in_conditional 2052 self.in_conditional = True 2053 self.process_statement_node(n.body) 2054 self.in_conditional = in_conditional 2055 2056 self.indent -= 1 2057 self.writeline("}") 2058 print >>self.out 2059 2060 # Special variable usage. 2061 2062 def get_temp_path(self): 2063 2064 """ 2065 Return the appropriate namespace path for temporary names in the current 2066 namespace. 2067 """ 2068 2069 if self.in_function: 2070 return self.get_namespace_path() 2071 else: 2072 return self.name 2073 2074 def record_temp(self, name): 2075 2076 """ 2077 Record the use of the temporary 'name' in the current namespace. At the 2078 class or module level, the temporary name is associated with the module, 2079 since the variable will then be allocated in the module's own main 2080 program. 2081 """ 2082 2083 path = self.get_temp_path() 2084 2085 init_item(self.temp_usage, path, list) 2086 self.temp_usage[path].append(name) 2087 2088 def remove_temps(self, names): 2089 2090 """ 2091 Remove 'names' from temporary storage allocations, each instance 2092 removing each request for storage. 2093 """ 2094 2095 path = self.get_temp_path() 2096 2097 for name in names: 2098 if self.uses_temp(path, name): 2099 self.temp_usage[path].remove(name) 2100 2101 def uses_temp(self, path, name): 2102 2103 """ 2104 Return whether the given namespace 'path' employs a temporary variable 2105 with the given 'name'. Note that 'path' should only be a module or a 2106 function or method, not a class. 2107 """ 2108 2109 return self.temp_usage.has_key(path) and name in self.temp_usage[path] 2110 2111 def make_negation(self, expr): 2112 2113 "Return a negated form of 'expr'." 2114 2115 result = NegationResult(expr) 2116 2117 # Negation discards the temporary results of its operand. 2118 2119 temps = expr.discards_temporary() 2120 if temps: 2121 self.remove_temps(temps) 2122 2123 return result 2124 2125 # Output generation. 2126 2127 def start_output(self): 2128 2129 "Write the declarations at the top of each source file." 2130 2131 print >>self.out, """\ 2132 #include "types.h" 2133 #include "exceptions.h" 2134 #include "ops.h" 2135 #include "progconsts.h" 2136 #include "progops.h" 2137 #include "progtypes.h" 2138 #include "main.h" 2139 """ 2140 2141 def start_unit(self): 2142 2143 "Record output within a generated function for later use." 2144 2145 self.out = StringIO() 2146 2147 def end_unit(self): 2148 2149 "Restore the output stream." 2150 2151 out = self.out 2152 self.out = self.out_toplevel 2153 return out 2154 2155 def flush_unit(self, name, out): 2156 2157 "Add declarations and generated code." 2158 2159 self.write_temporaries(name) 2160 print >>self.out 2161 out.seek(0) 2162 self.out.write(out.read()) 2163 2164 def start_module(self): 2165 2166 "Write the start of each module's main function." 2167 2168 print >>self.out, "void __main_%s()" % encode_path(self.name) 2169 print >>self.out, "{" 2170 self.indent += 1 2171 2172 # Define temporary variables, excluded from the module structure itself. 2173 2174 tempnames = [] 2175 2176 for n in self.importer.all_module_attrs[self.name]: 2177 if n.startswith("$t"): 2178 tempnames.append(encode_path(n)) 2179 2180 if tempnames: 2181 tempnames.sort() 2182 self.writeline("__attr %s;" % ", ".join(tempnames)) 2183 2184 self.start_unit() 2185 2186 def end_module(self): 2187 2188 "End each module by closing its main function." 2189 2190 out = self.end_unit() 2191 self.flush_unit(self.name, out) 2192 2193 self.indent -= 1 2194 print >>self.out, "}" 2195 2196 def start_function(self, name): 2197 2198 "Start the function having the given 'name'." 2199 2200 self.indent += 1 2201 2202 self.start_unit() 2203 2204 def end_function(self, name): 2205 2206 "End the function having the given 'name'." 2207 2208 out = self.end_unit() 2209 2210 # Write the signature at the top indentation level. 2211 2212 self.indent -= 1 2213 self.write_parameters(name) 2214 print >>self.out, "{" 2215 2216 # Obtain local names from parameters. 2217 2218 parameters = self.importer.function_parameters[name] 2219 locals = self.importer.function_locals[name].keys() 2220 names = [] 2221 volatile_names = [] 2222 2223 for n in locals: 2224 2225 # Filter out special names and parameters. Note that self is a local 2226 # regardless of whether it originally appeared in the parameters or 2227 # not. 2228 2229 if n.startswith("$l") or n in parameters or n == "self": 2230 continue 2231 if n in self.volatile_locals: 2232 volatile_names.append("%s = __NULL" % encode_path(n)) 2233 else: 2234 names.append("%s = __NULL" % encode_path(n)) 2235 2236 # Emit required local names at the function indentation level. 2237 2238 self.indent += 1 2239 2240 if names: 2241 names.sort() 2242 self.writeline("__attr %s;" % ", ".join(names)) 2243 2244 if volatile_names: 2245 volatile_names.sort() 2246 self.writeline("volatile __attr %s;" % ", ".join(volatile_names)) 2247 2248 self.flush_unit(name, out) 2249 2250 self.indent -= 1 2251 print >>self.out, "}" 2252 print >>self.out 2253 2254 def write_parameters(self, name): 2255 2256 """ 2257 For the function having the given 'name', write definitions of 2258 parameters found in the arguments array. 2259 """ 2260 2261 # Generate any self reference. 2262 2263 l = [] 2264 l.append("__attr __result") 2265 2266 if self.is_method(name): 2267 l.append("__attr self") 2268 else: 2269 l.append("__attr __self") 2270 2271 # Generate aliases for the parameters. 2272 2273 for parameter in self.importer.function_parameters[name]: 2274 l.append("%s__attr %s" % ( 2275 parameter in self.volatile_locals and "volatile " or "", 2276 encode_path(parameter))) 2277 2278 self.writeline("__attr %s(%s)" % ( 2279 encode_function_pointer(name), ", ".join(l))) 2280 2281 def write_temporaries(self, name): 2282 2283 "Write temporary storage employed by 'name'." 2284 2285 # Provide space for the recorded number of temporary variables. 2286 2287 if self.uses_temp(name, "__tmp_targets"): 2288 self.writeline("__attr __tmp_targets[%d];" % self.max_function_target) 2289 2290 if self.uses_temp(name, "__tmp_contexts"): 2291 self.writeline("__attr __tmp_contexts[%d];" % self.max_context_index) 2292 2293 if self.uses_temp(name, "__tmp_values"): 2294 self.writeline("__attr __tmp_values[%d];" % self.max_accessor_index) 2295 2296 if self.uses_temp(name, "__tmp_attr_refs"): 2297 self.writeline("__attr *__tmp_attr_refs[%d];" % self.max_attribute_ref_index) 2298 2299 if self.uses_temp(name, "__tmp_results"): 2300 self.writeline("__attr __tmp_results[%d] = {0};" % self.max_result_target) 2301 2302 if self.uses_temp(name, "__tmp_private_context"): 2303 self.writeline("__attr __tmp_private_context;") 2304 if self.uses_temp(name, "__tmp_target_value"): 2305 self.writeline("__attr __tmp_target_value;") 2306 if self.uses_temp(name, "__tmp_result"): 2307 self.writeline("__attr __tmp_result;") 2308 2309 module = self.importer.get_module(self.name) 2310 2311 if name in module.exception_namespaces: 2312 self.writeline("__exc __tmp_exc;") 2313 2314 def start_if(self, first, test_ref): 2315 statement = "%sif" % (not first and "else " or "") 2316 2317 # Consume logical results directly. 2318 2319 if isinstance(test_ref, LogicalResult): 2320 self.writeline("%s %s" % (statement, test_ref.apply_test())) 2321 temps = test_ref.discards_temporary() 2322 if temps: 2323 self.remove_temps(temps) 2324 else: 2325 self.writeline("%s (__BOOL(%s))" % (statement, test_ref)) 2326 2327 self.writeline("{") 2328 self.indent += 1 2329 2330 def end_if(self): 2331 self.indent -= 1 2332 self.writeline("}") 2333 2334 def start_else(self): 2335 self.writeline("else") 2336 self.writeline("{") 2337 self.indent += 1 2338 2339 def end_else(self): 2340 self.indent -= 1 2341 self.writeline("}") 2342 2343 def statement(self, expr): 2344 s = str(expr) 2345 if s: 2346 self.writestmt("%s;" % s) 2347 2348 def statements(self, results): 2349 for result in results: 2350 self.statement(result) 2351 2352 def writeline(self, s): 2353 print >>self.out, "%s%s" % (self.pad(), self.indenttext(s, self.indent + 1)) 2354 2355 def writestmt(self, s): 2356 self.writeline(s) 2357 2358 def write_comment(self, s): 2359 self.writestmt("/* %s */" % s) 2360 2361 def pad(self, extra=0): 2362 return (self.indent + extra) * self.tabstop 2363 2364 def indenttext(self, s, levels): 2365 lines = s.split("\n") 2366 out = [lines[0]] 2367 for line in lines[1:]: 2368 out.append(levels * self.tabstop + line) 2369 if line.endswith("("): 2370 levels += 1 2371 elif line.startswith(")"): 2372 levels -= 1 2373 return "\n".join(out) 2374 2375 # vim: tabstop=4 expandtab shiftwidth=4