1 #!/usr/bin/env python 2 3 """ 4 Translate programs. 5 6 Copyright (C) 2015-2018, 2023, 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.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 temps = set() 629 630 for sub in substituted: 631 if self.temp_subs.has_key(sub): 632 temps.add(self.temp_subs[sub]) 633 634 for temp in temps: 635 self.next_temp(temp) 636 637 # Get full final identity details. 638 639 if final_identity and not refs: 640 refs = set([self.importer.identify(final_identity)]) 641 642 del self.attrs[0] 643 return AttrResult(output, refs, location, 644 context_identity, context_identity_verified, 645 accessor_test, accessor_stored, attribute_ref_stored) 646 647 def init_substitutions(self): 648 649 """ 650 Initialise substitutions, defining temporary variable mappings, some of 651 which are also used as substitutions, together with operation mappings 652 used as substitutions in instructions defined by the optimiser. 653 """ 654 655 self.temp_subs = { 656 657 # Substitutions used by instructions. 658 659 "<private_context>" : "__tmp_private_context", 660 "<target_accessor>" : "__tmp_target_value", 661 662 # Mappings to be replaced by those given below. 663 664 "<accessor>" : "__tmp_values", 665 "<attr_ref>" : "__tmp_attr_refs", 666 "<context>" : "__tmp_contexts", 667 "<test_context_revert>" : "__tmp_contexts", 668 "<test_context_static>" : "__tmp_contexts", 669 "<set_context>" : "__tmp_contexts", 670 "<set_private_context>" : "__tmp_private_context", 671 "<set_accessor>" : "__tmp_values", 672 "<set_attr_ref>" : "__tmp_attr_refs", 673 "<set_target_accessor>" : "__tmp_target_value", 674 } 675 676 self.op_subs = { 677 "<accessor>" : "__get_accessor", 678 "<attr_ref>" : "__get_attr_ref", 679 "<context>" : "__get_context", 680 "<test_context_revert>" : "__test_context_revert", 681 "<test_context_static>" : "__test_context_static", 682 "<set_context>" : "__set_context", 683 "<set_private_context>" : "__set_private_context", 684 "<set_accessor>" : "__set_accessor", 685 "<set_attr_ref>" : "__set_attr_ref", 686 "<set_target_accessor>" : "__set_target_accessor", 687 } 688 689 def get_referenced_attributes(self, location): 690 691 """ 692 Convert 'location' to the form used by the deducer and retrieve any 693 identified attributes. 694 """ 695 696 # Determine whether any deduced references refer to the accessed 697 # attribute. 698 699 attrnames = location.attrnames 700 attrnames = attrnames and attrnames.split(".") 701 remaining = attrnames and len(attrnames) > 1 702 703 access_location = self.deducer.const_accesses.get(location) 704 705 if remaining and not access_location: 706 return set() 707 708 return self.deducer.get_references_for_access(access_location or location) 709 710 def get_referenced_attribute_invocations(self, location): 711 712 """ 713 Convert 'location' to the form used by the deducer and retrieve any 714 identified attribute invocation details. 715 """ 716 717 access_location = self.deducer.const_accesses.get(location) 718 return self.deducer.reference_invocations_unsuitable.get(access_location or location) 719 720 def get_accessor_kinds(self, location): 721 722 "Return the accessor kinds for 'location'." 723 724 return self.deducer.accessor_kinds.get(location) 725 726 def get_access_location(self, name, attrnames=None): 727 728 """ 729 Using the current namespace, the given 'name', and the 'attrnames' 730 employed in an access, return the access location. 731 """ 732 733 path = self.get_path_for_access() 734 735 # Get the location used by the deducer and optimiser and find any 736 # recorded access. 737 738 attrnames = attrnames and ".".join(self.attrs) 739 access_number = self.get_access_number(path, name, attrnames) 740 self.update_access_number(path, name, attrnames) 741 return AccessLocation(path, name, attrnames, access_number) 742 743 def get_access_number(self, path, name, attrnames): 744 access = name, attrnames 745 if self.attr_accesses.has_key(path) and self.attr_accesses[path].has_key(access): 746 return self.attr_accesses[path][access] 747 else: 748 return 0 749 750 def update_access_number(self, path, name, attrnames): 751 access = name, attrnames 752 if name: 753 init_item(self.attr_accesses, path, dict) 754 init_item(self.attr_accesses[path], access, lambda: 0) 755 self.attr_accesses[path][access] += 1 756 757 def get_accessor_location(self, name): 758 759 """ 760 Using the current namespace and the given 'name', return the accessor 761 location. 762 """ 763 764 path = self.get_path_for_access() 765 766 # Get the location used by the deducer and optimiser and find any 767 # recorded accessor. 768 769 version = self.get_accessor_number(path, name) 770 self.update_accessor_number(path, name) 771 return Location(path, name, None, version) 772 773 def get_accessor_number(self, path, name): 774 if self.attr_accessors.has_key(path) and self.attr_accessors[path].has_key(name): 775 return self.attr_accessors[path][name] 776 else: 777 return 0 778 779 def update_accessor_number(self, path, name): 780 if name: 781 init_item(self.attr_accessors, path, dict) 782 init_item(self.attr_accessors[path], name, lambda: 0) 783 self.attr_accessors[path][name] += 1 784 785 def process_class_node(self, n): 786 787 "Process the given class node 'n'." 788 789 class_name = self.get_object_path(n.name) 790 791 # Where a class is set conditionally or where the name may refer to 792 # different values, assign the name. 793 794 ref = self.importer.identify(class_name) 795 796 if not ref.static(): 797 self.process_assignment_for_object(n.name, 798 make_expression("__ATTRVALUE(&%s)" % encode_path(class_name))) 799 800 self.enter_namespace(n.name) 801 802 if self.have_object(): 803 self.write_comment("Class: %s" % class_name) 804 805 self.initialise_inherited_members(class_name) 806 807 self.process_structure(n) 808 self.write_comment("End class: %s" % class_name) 809 810 self.exit_namespace() 811 812 def initialise_inherited_members(self, class_name): 813 814 "Initialise members of 'class_name' inherited from its ancestors." 815 816 for name, path in self.importer.all_class_attrs[class_name].items(): 817 target = "%s.%s" % (class_name, name) 818 819 # Ignore attributes with definitions. 820 821 ref = self.importer.identify(target) 822 if ref: 823 continue 824 825 # Ignore special type attributes. 826 827 if is_type_attribute(name): 828 continue 829 830 # Reference inherited attributes. 831 832 ref = self.importer.identify(path) 833 if ref and not ref.static(): 834 parent, attrname = path.rsplit(".", 1) 835 836 self.writestmt("__store_via_attr_ref(__get_object_attr_ref(&%s, %s), __load_via_object(&%s, %s));" % ( 837 encode_path(class_name), name, 838 encode_path(parent), attrname 839 )) 840 841 def process_from_node(self, n): 842 843 "Process the given node 'n', importing from another module." 844 845 path = self.get_namespace_path() 846 847 # Attempt to obtain the referenced objects. 848 849 for name, alias in n.names: 850 if name == "*": 851 raise InspectError("Only explicitly specified names can be imported from modules.", path, n) 852 853 # Obtain the path of the assigned name. 854 855 objpath = self.get_object_path(alias or name) 856 857 # Obtain the identity of the name. 858 859 ref = self.importer.identify(objpath) 860 861 # Where the name is not static, assign the value. 862 863 if ref and not ref.static() and ref.get_name(): 864 self.writestmt("%s;" % 865 TrResolvedNameRef(alias or name, Reference("<var>", None, objpath), 866 expr=TrResolvedNameRef(name, ref))) 867 868 def process_function_body_node(self, n): 869 870 """ 871 Process the given function, lambda, if expression or list comprehension 872 node 'n', generating the body. 873 """ 874 875 function_name = self.get_namespace_path() 876 self.start_function(function_name) 877 878 # Process the function body. 879 880 in_conditional = self.in_conditional 881 self.in_conditional = False 882 883 # Reset temporary storage counters and limits. 884 885 self.reset_temp_limits() 886 887 # Reset result target storage details. To be effective, storage 888 # locations are not reused between statements. 889 890 self.max_result_target = 0 891 self.result_target = 0 892 893 # Volatile locals for exception handling. 894 895 self.volatile_locals = set() 896 897 # Process any guards defined for the parameters. 898 899 for name in self.importer.function_parameters.get(function_name): 900 self.generate_guard(name) 901 902 # Also support self in methods, since some mix-in methods may only work 903 # with certain descendant classes. 904 905 if self.in_method(): 906 self.generate_guard("self") 907 908 # Make assignments for .name entries in the parameters, provided this is 909 # a method. 910 911 if self.in_method(): 912 for name in self.importer.function_attr_initialisers.get(function_name) or []: 913 914 # Treat each assignment as a separate statement. 915 916 self.reset_temp_counters() 917 918 self.process_assignment_node( 919 compiler.ast.AssAttr(compiler.ast.Name("self"), name, "OP_ASSIGN"), 920 compiler.ast.Name(name)) 921 922 # Produce the body and any additional return statement. 923 924 is_lambda = isinstance(n, compiler.ast.Lambda) 925 926 expr = self.process_statement_node(n.code, is_lambda) or \ 927 self.in_method() and \ 928 function_name.rsplit(".", 1)[-1] == "__init__" and \ 929 TrResolvedNameRef("self", self.importer.function_locals[function_name]["self"]) or \ 930 PredefinedConstantRef("None") 931 932 if not isinstance(expr, ReturnRef): 933 self.writestmt("return %s;" % expr) 934 935 self.in_conditional = in_conditional 936 937 self.end_function(function_name) 938 939 def generate_guard(self, name): 940 941 """ 942 Get the accessor details for 'name', found in the current namespace, and 943 generate any guards defined for it. 944 """ 945 946 # Obtain the location, keeping track of assignment versions. 947 948 location = self.get_accessor_location(name) 949 test = self.deducer.accessor_guard_tests.get(location) 950 951 # Generate any guard from the deduced information. 952 953 if test: 954 guard, guard_type = test 955 956 if guard == "specific": 957 ref = first(self.deducer.accessor_all_types[location]) 958 argstr = "&%s" % encode_path(ref.get_origin()) 959 elif guard == "common": 960 ref = first(self.deducer.accessor_all_general_types[location]) 961 argstr = encode_path(encode_type_attribute(ref.get_origin())) 962 else: 963 return 964 965 # Write a test that raises a TypeError upon failure. 966 967 self.writestmt("if (!__test_%s_%s(__VALUE(%s), %s)) __raise_type_error();" % ( 968 guard, guard_type, encode_path(name), argstr)) 969 970 def process_function_node(self, n): 971 972 """ 973 Process the given function, lambda, if expression or list comprehension 974 node 'n', generating any initialisation statements. 975 """ 976 977 # Where a function is declared conditionally, use a separate name for 978 # the definition, and assign the definition to the stated name. 979 980 original_name = n.name 981 982 if self.in_conditional or self.in_function: 983 name = self.get_lambda_name() 984 else: 985 name = n.name 986 987 objpath = self.get_object_path(name) 988 989 # Obtain details of the defaults. 990 991 defaults = self.process_function_defaults(n, name, objpath) 992 if defaults: 993 for default in defaults: 994 self.writeline("%s;" % default) 995 996 # Where a function is set conditionally or where the name may refer to 997 # different values, assign the name. 998 999 ref = self.importer.identify(objpath) 1000 1001 if self.in_conditional or self.in_function: 1002 self.process_assignment_for_object(original_name, compiler.ast.Name(name)) 1003 elif not ref.static(): 1004 context = self.is_method(objpath) 1005 1006 self.process_assignment_for_object(original_name, 1007 make_expression("__ATTRVALUE(&%s)" % encode_path(objpath))) 1008 1009 def process_function_defaults(self, n, name, objpath, instance_name=None): 1010 1011 """ 1012 Process the given function or lambda node 'n', initialising defaults 1013 that are dynamically set. The given 'name' indicates the name of the 1014 function. The given 'objpath' indicates the origin of the function. 1015 The given 'instance_name' indicates the name of any separate instance 1016 of the function created to hold the defaults. 1017 1018 Return a list of operations setting defaults on a function instance. 1019 """ 1020 1021 function_name = self.get_object_path(name) 1022 function_defaults = self.importer.function_defaults.get(function_name) 1023 if not function_defaults: 1024 return None 1025 1026 # Determine whether any unidentified defaults are involved. 1027 1028 for argname, default in function_defaults: 1029 if not default.static(): 1030 break 1031 else: 1032 return None 1033 1034 # Handle bound methods. 1035 1036 if not instance_name: 1037 instance_name = "&%s" % encode_path(objpath) 1038 else: 1039 instance_name = "__VALUE(%s)" % instance_name 1040 1041 # Where defaults are involved but cannot be identified, obtain a new 1042 # instance of the lambda and populate the defaults. 1043 1044 defaults = [] 1045 1046 # Join the original defaults with the inspected defaults. 1047 1048 original_defaults = [(argname, default) for (argname, default) in compiler.ast.get_defaults(n) if default] 1049 1050 for i, (original, inspected) in enumerate(map(None, original_defaults, function_defaults)): 1051 1052 # Obtain any reference for the default. 1053 1054 if original: 1055 argname, default = original 1056 name_ref = self.process_structure_node(default) 1057 elif inspected: 1058 argname, default = inspected 1059 name_ref = TrResolvedNameRef(argname, default) 1060 else: 1061 continue 1062 1063 # Generate default initialisers except when constants are employed. 1064 # Constants should be used when populating the function structures. 1065 1066 if name_ref and not isinstance(name_ref, TrConstantValueRef): 1067 defaults.append("__SETDEFAULT(%s, %s, %s)" % (instance_name, i, name_ref)) 1068 1069 return defaults 1070 1071 def process_if_node(self, n): 1072 1073 """ 1074 Process the given "if" node 'n'. 1075 """ 1076 1077 first = True 1078 for test, body in n.tests: 1079 test_ref = self.process_statement_node(test) 1080 self.start_if(first, test_ref) 1081 1082 in_conditional = self.in_conditional 1083 self.in_conditional = True 1084 self.process_statement_node(body) 1085 self.in_conditional = in_conditional 1086 1087 self.end_if() 1088 first = False 1089 1090 if n.else_: 1091 self.start_else() 1092 self.process_statement_node(n.else_) 1093 self.end_else() 1094 1095 print >>self.out 1096 1097 def process_invocation_node(self, n): 1098 1099 "Process the given invocation node 'n'." 1100 1101 # Process the expression. 1102 1103 expr = self.process_structure_node(n.node) 1104 1105 # Obtain details of the invocation expression. 1106 1107 objpath = expr.get_origin() 1108 location = expr.access_location() 1109 refs = expr.references() 1110 1111 # Identified target details. 1112 1113 target = None 1114 target_structure = None 1115 1116 # Specific function target information. 1117 1118 function = None 1119 1120 # Instantiation involvement. 1121 1122 instantiation = False 1123 literal_instantiation = False 1124 1125 # Invocation requirements. 1126 1127 context_required = True 1128 have_access_context = isinstance(expr, AttrResult) 1129 1130 # The context identity is merely the thing providing the context. 1131 # A verified context is one that does not need further testing for 1132 # suitability. 1133 1134 context_identity = have_access_context and expr.context() 1135 context_verified = have_access_context and expr.context_verified() 1136 1137 # The presence of any test operations in the accessor expression. 1138 # With such operations present, the expression cannot be eliminated. 1139 1140 tests_accessor = have_access_context and expr.tests_accessor() 1141 stores_accessor = have_access_context and expr.stores_accessor() 1142 1143 # Parameter details and parameter list dimensions. 1144 1145 parameters = None 1146 num_parameters = None 1147 num_defaults = None 1148 1149 # Obtain details of the callable and of its parameters. 1150 1151 # Literals may be instantiated specially. 1152 1153 if expr.is_name() and expr.name.startswith("$L") and objpath: 1154 instantiation = literal_instantiation = objpath 1155 target = encode_literal_instantiator(objpath) 1156 context_required = False 1157 1158 # Identified targets employ function pointers directly. 1159 1160 elif objpath: 1161 parameters = self.importer.function_parameters.get(objpath) 1162 function_defaults = self.importer.function_defaults.get(objpath) 1163 num_parameters = parameters and len(parameters) or 0 1164 num_defaults = function_defaults and len(function_defaults) or 0 1165 1166 # Class invocation involves instantiators. 1167 1168 if expr.has_kind("<class>"): 1169 instantiation = objpath 1170 target = encode_instantiator_pointer(objpath) 1171 init_ref = self.importer.all_class_attrs[objpath]["__init__"] 1172 target_structure = "&%s" % encode_path(init_ref) 1173 context_required = False 1174 1175 # Only plain functions and bound methods employ function pointers. 1176 1177 elif expr.has_kind("<function>"): 1178 function = objpath 1179 1180 # Test for functions and methods. 1181 1182 context_required = self.is_method(objpath) 1183 1184 accessor_kinds = location and self.get_accessor_kinds(location) 1185 1186 instance_accessor = accessor_kinds and \ 1187 len(accessor_kinds) == 1 and \ 1188 first(accessor_kinds) == "<instance>" 1189 1190 # Only identify certain bound methods or functions. 1191 1192 if not context_required or instance_accessor: 1193 target = encode_function_pointer(objpath) 1194 1195 # Access bound method defaults even if it is not clear whether 1196 # the accessor is appropriate. 1197 1198 target_structure = "&%s" % encode_path(objpath) 1199 1200 # Other targets are retrieved at run-time. 1201 1202 else: 1203 if location: 1204 attrnames = location.attrnames 1205 attrname = attrnames and attrnames.rsplit(".", 1)[-1] 1206 1207 # Determine common aspects of any identifiable targets. 1208 1209 if attrname or refs: 1210 all_params = set() 1211 all_defaults = set() 1212 min_params = set() 1213 max_params = set() 1214 1215 # Employ references from the expression or find all 1216 # possible attributes for the given attribute name. 1217 1218 refs = refs or self.get_attributes_for_attrname(attrname) 1219 1220 # Obtain parameters and defaults for each possible target. 1221 1222 for ref in refs: 1223 origin = ref.get_origin() 1224 params = self.importer.function_parameters.get(origin) 1225 1226 defaults = self.importer.function_defaults.get(origin) 1227 if defaults is not None: 1228 all_defaults.add(tuple(defaults)) 1229 1230 if params is not None: 1231 all_params.add(tuple(params)) 1232 min_params.add(len(params) - (defaults and len(defaults) or 0)) 1233 max_params.add(len(params)) 1234 else: 1235 refs = set() 1236 break 1237 1238 # Where the parameters and defaults are always the same, 1239 # permit populating them in advance. 1240 1241 if refs: 1242 if self.uses_keyword_arguments(n): 1243 if len(all_params) == 1 and (not all_defaults or len(all_defaults) == 1): 1244 parameters = first(all_params) 1245 function_defaults = all_defaults and first(all_defaults) or [] 1246 num_parameters = parameters and len(parameters) or 0 1247 num_defaults = function_defaults and len(function_defaults) or 0 1248 else: 1249 if len(min_params) == 1 and len(max_params) == 1: 1250 num_parameters = first(max_params) 1251 num_defaults = first(max_params) - first(min_params) 1252 1253 # Some information about the target may be available and be used to 1254 # provide warnings about argument compatibility. 1255 1256 if self.importer.give_warning("args"): 1257 unsuitable = self.get_referenced_attribute_invocations(location) 1258 1259 if unsuitable: 1260 for ref in unsuitable: 1261 _objpath = ref.get_origin() 1262 print >>sys.stderr, \ 1263 "In %s, at line %d, inappropriate number of " \ 1264 "arguments given. Need %d arguments to call %s." % ( 1265 self.get_namespace_path(), n.lineno, 1266 len(self.importer.function_parameters[_objpath]), 1267 _objpath) 1268 1269 # Logical statement about available parameter information. 1270 1271 known_parameters = num_parameters is not None 1272 1273 # The source of context information: target or temporary. 1274 1275 need_context_target = context_required and not have_access_context 1276 1277 need_context_stored = context_required and context_identity and \ 1278 context_identity.startswith("__get_context") 1279 1280 # Determine any readily-accessible target identity. 1281 1282 target_named = expr.is_name() and str(expr) or None 1283 target_identity = target or target_named 1284 1285 # Use of target information to populate defaults. 1286 1287 defaults_target_var = not (parameters and function_defaults is not None) and \ 1288 known_parameters and len(n.args) < num_parameters 1289 1290 # Use of a temporary target variable in these situations: 1291 # 1292 # A target provided by an expression needed for defaults. 1293 # 1294 # A target providing the context but not using a name to do so. 1295 # 1296 # A target expression involving the definition of a context which may 1297 # then be evaluated and stored to ensure that the context is available 1298 # during argument evaluation. 1299 # 1300 # An expression featuring an accessor test. 1301 1302 need_target_stored = defaults_target_var and not target_identity or \ 1303 need_context_target and not target_identity or \ 1304 need_context_stored or \ 1305 tests_accessor and not target 1306 1307 # Define stored target details. 1308 1309 target_stored = "__tmp_targets[%d]" % self.function_target 1310 target_var = need_target_stored and target_stored or target_identity 1311 1312 if need_target_stored: 1313 self.record_temp("__tmp_targets") 1314 1315 if need_context_stored: 1316 self.record_temp("__tmp_contexts") 1317 1318 if stores_accessor: 1319 self.record_temp("__tmp_values") 1320 1321 # Employ result targets only in functions. 1322 1323 if self.in_function: 1324 if self.result_target_name: 1325 result_target = self.result_target_name 1326 self.result_target_name = None 1327 else: 1328 result_target = "__tmp_results[%d]" % self.result_target 1329 self.record_temp("__tmp_results") 1330 self.next_result() 1331 else: 1332 result_target = None 1333 1334 # Arguments are presented in a temporary frame array with any context 1335 # always being the first argument. Where it would be unused, it may be 1336 # set to null. 1337 1338 if context_required: 1339 if have_access_context: 1340 context_arg = context_identity 1341 else: 1342 context_arg = "__CONTEXT_AS_VALUE(%s)" % target_var 1343 else: 1344 context_arg = "__NULL" 1345 1346 # Start with result target and context arguments for each invocation. 1347 1348 args = [result_target or "__NULL", context_arg] 1349 reserved_args = 2 1350 1351 # Complete the array with null values, permitting tests for a complete 1352 # set of arguments. 1353 1354 args += [None] * (num_parameters is None and len(n.args) or num_parameters is not None and num_parameters or 0) 1355 kwcodes = [] 1356 kwargs = [] 1357 1358 # Any invocations in the arguments will store target details in a 1359 # different location. 1360 1361 function_target = self.function_target 1362 context_index = self.context_index 1363 accessor_index = self.accessor_index 1364 1365 if need_target_stored: 1366 self.next_target() 1367 1368 if need_context_stored: 1369 self.next_context() 1370 1371 if stores_accessor: 1372 self.next_accessor() 1373 1374 in_parameter_list = self.in_parameter_list 1375 self.in_parameter_list = True 1376 1377 for i, arg in enumerate(n.args): 1378 argexpr = self.process_structure_node(arg) 1379 1380 # Convert any attributes indicating value replacement. 1381 1382 if isinstance(argexpr, InvocationResult) and argexpr.result_target: 1383 argexprstr = "__set_attr(&%s, %s)" % (argexpr.result_target, argexpr) 1384 else: 1385 argexprstr = str(argexpr) 1386 1387 # Store a keyword argument, either in the argument list or 1388 # in a separate keyword argument list for subsequent lookup. 1389 1390 if isinstance(arg, compiler.ast.Keyword): 1391 1392 # With knowledge of the target, store the keyword 1393 # argument directly. 1394 1395 if parameters: 1396 try: 1397 argnum = parameters.index(arg.name) 1398 except ValueError: 1399 raise TranslateError("Argument %s is not recognised." % arg.name, 1400 self.get_namespace_path(), n) 1401 args[argnum + reserved_args] = argexprstr 1402 1403 # Otherwise, store the details in a separate collection. 1404 1405 else: 1406 kwargs.append(argexprstr) 1407 kwcodes.append("{%s, %s}" % ( 1408 encode_ppos(arg.name), encode_pcode(arg.name))) 1409 1410 # Store non-keyword arguments in the argument list, rejecting 1411 # superfluous arguments. 1412 1413 else: 1414 try: 1415 args[i + reserved_args] = argexprstr 1416 except IndexError: 1417 raise TranslateError("Too many arguments specified.", 1418 self.get_namespace_path(), n) 1419 1420 # Reference the current target again. 1421 1422 self.in_parameter_list = in_parameter_list 1423 1424 if not self.in_parameter_list: 1425 self.function_target = function_target 1426 self.context_index = context_index 1427 self.accessor_index = accessor_index 1428 1429 # Defaults are added to the frame where arguments are missing. 1430 1431 if parameters and function_defaults is not None: 1432 1433 # Visit each default and set any missing arguments. Where keyword 1434 # arguments have been used, the defaults must be inspected and, if 1435 # necessary, inserted into gaps in the argument list. 1436 1437 for i, (argname, default) in enumerate(function_defaults): 1438 argnum = parameters.index(argname) 1439 if not args[argnum + reserved_args]: 1440 args[argnum + reserved_args] = "__GETDEFAULT(%s, %d)" % (target_structure, i) 1441 1442 elif known_parameters: 1443 1444 # No specific parameter details are provided, but no keyword 1445 # arguments are used. Thus, defaults can be supplied using position 1446 # information only. 1447 1448 i = len(n.args) 1449 pos = i - (num_parameters - num_defaults) 1450 while i < num_parameters: 1451 args[i + reserved_args] = "__GETDEFAULT(%s.value, %d)" % (target_var, pos) 1452 i += 1 1453 pos += 1 1454 1455 # Test for missing arguments. 1456 1457 if None in args: 1458 raise TranslateError("Not all arguments supplied.", 1459 self.get_namespace_path(), n) 1460 1461 # Encode the arguments. 1462 1463 # Where literal instantiation is occurring, add an argument indicating 1464 # the number of values. The result target and context are excluded. 1465 1466 if literal_instantiation: 1467 argstr = "%d, %s" % (len(args) - reserved_args, ", ".join(args[reserved_args:])) 1468 else: 1469 argstr = ", ".join(args) 1470 1471 kwargstr = kwargs and ("__ARGS(%s)" % ", ".join(kwargs)) or "0" 1472 kwcodestr = kwcodes and ("__KWARGS(%s)" % ", ".join(kwcodes)) or "0" 1473 1474 # First, the invocation expression is presented. 1475 1476 stages = [] 1477 emit = stages.append 1478 1479 # Assign and yield any stored target. 1480 # The context may be set in the expression. 1481 1482 if need_target_stored: 1483 emit("%s = %s" % (target_var, expr)) 1484 target_expr = target_var 1485 1486 # Otherwise, retain the expression for later use. 1487 1488 else: 1489 target_expr = str(expr) 1490 1491 # Any specific callable is then obtained for invocation. 1492 1493 if target: 1494 1495 # An expression involving a test of the accessor providing the target. 1496 # This must be emitted in order to perform the test. 1497 1498 if tests_accessor: 1499 emit(str(expr)) 1500 1501 emit(target) 1502 1503 # Methods accessed via unidentified accessors are obtained for 1504 # invocation. 1505 1506 elif function: 1507 if context_required: 1508 1509 # Avoid further context testing if appropriate. 1510 1511 if have_access_context and context_verified: 1512 emit("__get_function_member(%s)" % target_expr) 1513 1514 # Otherwise, test the context for the function/method. 1515 1516 else: 1517 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1518 else: 1519 emit("_get_function_member(%s)" % target_expr) 1520 1521 # With known parameters, the target can be tested. 1522 1523 elif known_parameters: 1524 if self.always_callable(refs): 1525 if context_verified: 1526 emit("__get_function_member(%s)" % target_expr) 1527 else: 1528 emit("__get_function(%s, %s)" % (context_arg, target_expr)) 1529 else: 1530 emit("__check_and_get_function(%s, %s)" % (context_arg, target_expr)) 1531 1532 # With a known target, the function is obtained directly and called. 1533 # By putting the invocation at the end of the final element in the 1534 # instruction sequence (the stages), the result becomes the result of 1535 # the sequence. Moreover, the parameters become part of the sequence 1536 # and thereby participate in a guaranteed evaluation order. 1537 1538 if target or function or known_parameters: 1539 stages[-1] += "(%s)" % argstr 1540 if instantiation: 1541 return InstantiationResult(instantiation, stages) 1542 else: 1543 return InvocationResult(result_target, stages) 1544 1545 # With unknown targets, the generic invocation function is applied to 1546 # the callable and argument collections. 1547 1548 else: 1549 emit("__invoke(\n%s,\n%d, %d, %s, %s,\n%d, %s\n)" % ( 1550 target_expr, 1551 self.always_callable(refs) and 1 or 0, 1552 len(kwargs), kwcodestr, kwargstr, 1553 len(args), "__ARGS(%s)" % argstr)) 1554 return InvocationResult(result_target, stages) 1555 1556 def reset_temp_counters(self): 1557 1558 "Reset the target counters." 1559 1560 self.function_target = 0 1561 self.context_index = 0 1562 self.accessor_index = 0 1563 self.attribute_ref_index = 0 1564 self.result_target_name = None 1565 1566 def reset_temp_limits(self): 1567 1568 "Reset the target counter limits." 1569 1570 self.max_function_target = 0 1571 self.max_context_index = 0 1572 self.max_accessor_index = 0 1573 self.max_attribute_ref_index = 0 1574 1575 def next_temp(self, name): 1576 1577 "Allocate the next temporary storage element for 'name'." 1578 1579 if name == "__tmp_results": 1580 self.next_result() 1581 elif name == "__tmp_targets": 1582 self.next_target() 1583 elif name == "__tmp_contexts": 1584 self.next_context() 1585 elif name == "__tmp_values": 1586 self.next_accessor() 1587 elif name == "__tmp_attr_refs": 1588 self.next_attribute_ref() 1589 elif name in ("__tmp_private_context", "__tmp_target_value", "__tmp_result"): 1590 pass 1591 else: 1592 raise TranslateError("Temporary storage %s is not recognised." % name, 1593 self.get_namespace_path()) 1594 1595 self.record_temp(name) 1596 1597 def next_result(self): 1598 1599 "Allocate the next result target storage." 1600 1601 self.result_target += 1 1602 self.max_result_target = max(self.result_target, self.max_result_target) 1603 1604 def next_target(self): 1605 1606 "Allocate the next function target storage." 1607 1608 self.function_target += 1 1609 self.max_function_target = max(self.function_target, self.max_function_target) 1610 1611 def next_context(self): 1612 1613 "Allocate the next context value storage." 1614 1615 self.context_index += 1 1616 self.max_context_index = max(self.context_index, self.max_context_index) 1617 1618 def next_accessor(self): 1619 1620 "Allocate the next accessor value storage." 1621 1622 self.accessor_index += 1 1623 self.max_accessor_index = max(self.accessor_index, self.max_accessor_index) 1624 1625 def next_attribute_ref(self): 1626 1627 "Allocate the next attribute reference value storage." 1628 1629 self.attribute_ref_index += 1 1630 self.max_attribute_ref_index = max(self.attribute_ref_index, self.max_attribute_ref_index) 1631 1632 def always_callable(self, refs): 1633 1634 "Determine whether all 'refs' are callable." 1635 1636 if not refs: 1637 return False 1638 1639 for ref in refs: 1640 if not ref.has_kind("<function>") and not self.importer.get_attributes(ref, "__fn__"): 1641 return False 1642 1643 return True 1644 1645 def need_default_arguments(self, objpath, nargs): 1646 1647 """ 1648 Return whether any default arguments are needed when invoking the object 1649 given by 'objpath'. 1650 """ 1651 1652 parameters = self.importer.function_parameters.get(objpath) 1653 return nargs < len(parameters) 1654 1655 def uses_keyword_arguments(self, n): 1656 1657 "Return whether invocation node 'n' uses keyword arguments." 1658 1659 for arg in enumerate(n.args): 1660 if isinstance(arg, compiler.ast.Keyword): 1661 return True 1662 1663 return False 1664 1665 def get_attributes_for_attrname(self, attrname): 1666 1667 "Return a set of all attributes exposed by 'attrname'." 1668 1669 usage = [(attrname, True, False)] 1670 class_types = self.deducer.get_class_types_for_usage(usage) 1671 instance_types = self.deducer.get_instance_types_for_usage(usage) 1672 module_types = self.deducer.get_module_types_for_usage(usage) 1673 attrs = set() 1674 1675 for ref in combine_types(class_types, instance_types, module_types): 1676 attrs.update(self.importer.get_attributes(ref, attrname)) 1677 1678 return attrs 1679 1680 def process_lambda_node(self, n): 1681 1682 "Process the given lambda node 'n'." 1683 1684 name = self.get_lambda_name() 1685 function_name = self.get_object_path(name) 1686 instance_name = "__get_accessor(%d)" % self.accessor_index 1687 1688 defaults = self.process_function_defaults(n, name, function_name, instance_name) 1689 1690 # Without defaults, produce an attribute referring to the function. 1691 1692 if not defaults: 1693 return make_expression("__ATTRVALUE(&%s)" % encode_path(function_name)) 1694 1695 # With defaults, copy the function structure and set the defaults on the 1696 # copy. 1697 1698 else: 1699 self.record_temp("__tmp_values") 1700 accessor_index = self.accessor_index 1701 self.next_accessor() 1702 return make_expression("""\ 1703 (__set_accessor(%d, __ATTRVALUE(__COPY(&%s, sizeof(%s)))), 1704 %s, 1705 __get_accessor(%d))""" % ( 1706 accessor_index, 1707 encode_path(function_name), 1708 encode_symbol("obj", function_name), 1709 ", ".join(defaults), 1710 accessor_index)) 1711 1712 def process_logical_node(self, n): 1713 1714 "Process the given operator node 'n'." 1715 1716 self.record_temp("__tmp_result") 1717 1718 conjunction = isinstance(n, compiler.ast.And) 1719 results = [] 1720 1721 for node in n.nodes: 1722 results.append(self.process_structure_node(node)) 1723 1724 return LogicalOperationResult(results, conjunction) 1725 1726 def process_name_node(self, n, expr=None, process_expr=False): 1727 1728 "Process the given name node 'n' with the optional assignment 'expr'." 1729 1730 # Determine whether the name refers to a static external entity. 1731 1732 if n.name in predefined_constants: 1733 return PredefinedConstantRef(n.name, expr) 1734 1735 # Convert literal references, operator function names, and print 1736 # function names to references. 1737 1738 elif n.name.startswith("$L") or n.name.startswith("$op") or \ 1739 n.name.startswith("$seq") or n.name.startswith("$print"): 1740 1741 ref, paths = self.importer.get_module(self.name).special[n.name] 1742 return TrResolvedNameRef(n.name, ref) 1743 1744 # Get the appropriate name for the name reference, using the same method 1745 # as in the inspector. 1746 1747 path = self.get_namespace_path() 1748 objpath = self.get_object_path(n.name) 1749 1750 # Determine any assigned globals. 1751 1752 globals = self.importer.get_module(self.name).scope_globals.get(path) 1753 1754 # Explicitly declared globals. 1755 1756 if globals and n.name in globals: 1757 objpath = self.get_global_path(n.name) 1758 is_global = True 1759 1760 # Implicitly referenced globals in functions. 1761 1762 elif self.in_function: 1763 is_global = n.name not in self.importer.function_locals[path] 1764 1765 # Implicitly referenced globals elsewhere. 1766 1767 else: 1768 namespace = self.importer.identify(path) 1769 is_global = not self.importer.get_attributes(namespace, n.name) 1770 1771 # Get the static identity of the name. 1772 1773 ref = self.importer.identify(objpath) 1774 if ref and not ref.get_name(): 1775 ref = ref.alias(objpath) 1776 1777 # Obtain any resolved names for non-assignment names. 1778 1779 if not expr and not ref and self.in_function: 1780 locals = self.importer.function_locals.get(path) 1781 ref = locals and locals.get(n.name) 1782 1783 # Find any invocation or alias details. 1784 1785 name = self.get_name_for_tracking(n.name, is_global=is_global) 1786 location = not expr and self.get_access_location(name) or None 1787 1788 # Mark any local assignments as volatile in exception blocks. 1789 1790 if expr and self.in_function and not is_global and self.in_try_except: 1791 self.make_volatile(n.name) 1792 1793 # Set the replacement target. Note that this will not apply to all 1794 # objects, with only floats supporting replaceable values. 1795 1796 if expr: 1797 # Prevent parameters from becoming result targets. Otherwise, they 1798 # may inadvertently cause the modification of the supplied object. 1799 1800 parameters = self.importer.function_parameters.get(path) 1801 1802 if not parameters or n.name not in parameters: 1803 target_ref = TrResolvedNameRef(n.name, ref, is_global=is_global, 1804 location=location) 1805 self.result_target_name = str(target_ref) 1806 else: 1807 self.result_target_name = None 1808 1809 # Expression processing is deferred until after any result target has 1810 # been set. 1811 1812 if process_expr: 1813 expr = self.process_structure_node(expr) 1814 1815 # Qualified names are used for resolved static references or for 1816 # static namespace members. The reference should be configured to return 1817 # such names. 1818 1819 name_ref = TrResolvedNameRef(n.name, ref, expr=expr, is_global=is_global, 1820 location=location) 1821 1822 return not expr and self.get_aliases(name_ref) or name_ref 1823 1824 def get_aliases(self, name_ref): 1825 1826 "Return alias references for the given 'name_ref'." 1827 1828 location = name_ref.access_location() 1829 accessor_locations = self.deducer.access_index.get(location) 1830 1831 if not accessor_locations: 1832 return None 1833 1834 refs = set() 1835 1836 for accessor_location in accessor_locations: 1837 alias_refs = self.deducer.referenced_objects.get(accessor_location) 1838 if alias_refs: 1839 refs.update(alias_refs) 1840 1841 if refs: 1842 return AliasResult(name_ref, refs, location) 1843 else: 1844 return None 1845 1846 def make_volatile(self, name): 1847 1848 "Record 'name' as volatile in the current namespace." 1849 1850 self.volatile_locals.add(name) 1851 1852 def process_not_node(self, n): 1853 1854 "Process the given operator node 'n'." 1855 1856 return self.make_negation(self.process_structure_node(n.expr)) 1857 1858 def process_raise_node(self, n): 1859 1860 "Process the given raise node 'n'." 1861 1862 # NOTE: Determine which raise statement variants should be permitted. 1863 1864 if n.expr1: 1865 1866 # Names with accompanying arguments are treated like invocations. 1867 1868 if n.expr2: 1869 call = compiler.ast.CallFunc(n.expr1, [n.expr2]) 1870 exc = self.process_structure_node(call) 1871 self.writestmt("__Raise(%s);" % exc) 1872 1873 # Raise instances, testing the kind at run-time if necessary and 1874 # instantiating any non-instance. 1875 1876 else: 1877 exc = self.process_structure_node(n.expr1) 1878 1879 if isinstance(exc, TrInstanceRef) or exc.is_well_defined_instance(): 1880 self.writestmt("__Raise(%s);" % exc) 1881 else: 1882 self.writestmt("__Raise(__ensure_instance(%s));" % exc) 1883 else: 1884 self.writestmt("__Throw(__tmp_exc);") 1885 1886 def process_return_node(self, n): 1887 1888 "Process the given return node 'n'." 1889 1890 if self.in_function: 1891 self.result_target_name = "__result" 1892 1893 expr = self.process_structure_node(n.value) or PredefinedConstantRef("None") 1894 1895 if self.in_try_finally or self.in_try_except: 1896 self.writestmt("__Return(%s);" % expr) 1897 else: 1898 self.writestmt("return %s;" % expr) 1899 1900 return ReturnRef() 1901 1902 def process_try_node(self, n): 1903 1904 """ 1905 Process the given "try...except" node 'n'. 1906 """ 1907 1908 in_try_except = self.in_try_except 1909 self.in_try_except = True 1910 1911 # Use macros to implement exception handling. 1912 1913 self.writestmt("__Try") 1914 self.writeline("{") 1915 self.indent += 1 1916 self.process_statement_node(n.body) 1917 1918 # Put the else statement in another try block that handles any raised 1919 # exceptions and converts them to exceptions that will not be handled by 1920 # the main handling block. 1921 1922 if n.else_: 1923 self.writestmt("__Try") 1924 self.writeline("{") 1925 self.indent += 1 1926 self.process_statement_node(n.else_) 1927 self.indent -= 1 1928 self.writeline("}") 1929 self.writeline("__Catch (__tmp_exc)") 1930 self.writeline("{") 1931 self.indent += 1 1932 self.writeline("if (__tmp_exc.raising) __RaiseElse(__tmp_exc.arg);") 1933 self.writeline("else if (__tmp_exc.completing) __Throw(__tmp_exc);") 1934 self.indent -= 1 1935 self.writeline("}") 1936 1937 # Complete the try block and enter the finally block, if appropriate. 1938 1939 if self.in_try_finally: 1940 self.writestmt("__Complete;") 1941 1942 self.indent -= 1 1943 self.writeline("}") 1944 1945 self.in_try_except = in_try_except 1946 1947 # Handlers are tests within a common handler block. 1948 1949 self.writeline("__Catch (__tmp_exc)") 1950 self.writeline("{") 1951 self.indent += 1 1952 1953 # Introduce an if statement to handle the completion of a try block. 1954 1955 self.process_try_completion() 1956 1957 # Handle exceptions in else blocks converted to __RaiseElse, converting 1958 # them back to normal exceptions. 1959 1960 if n.else_: 1961 self.writeline("else if (__tmp_exc.raising_else) __Raise(__tmp_exc.arg);") 1962 1963 # Exception handling. 1964 1965 for name, var, handler in n.handlers: 1966 1967 # Test for specific exceptions. 1968 1969 if name is not None: 1970 name_ref = self.process_statement_node(name) 1971 self.writeline("else if (__ISINSTANCE(__tmp_exc.arg, %s))" % name_ref) 1972 else: 1973 self.writeline("else if (1)") 1974 1975 self.writeline("{") 1976 self.indent += 1 1977 1978 # Establish the local for the handler. 1979 1980 if var is not None: 1981 self.writestmt("%s;" % self.process_name_node(var, make_expression("__tmp_exc.arg"))) 1982 1983 if handler is not None: 1984 self.process_statement_node(handler) 1985 1986 self.indent -= 1 1987 self.writeline("}") 1988 1989 # Re-raise unhandled exceptions. 1990 1991 self.writeline("else __Throw(__tmp_exc);") 1992 1993 # End the handler block. 1994 1995 self.indent -= 1 1996 self.writeline("}") 1997 print >>self.out 1998 1999 def process_try_finally_node(self, n): 2000 2001 """ 2002 Process the given "try...finally" node 'n'. 2003 """ 2004 2005 in_try_finally = self.in_try_finally 2006 self.in_try_finally = True 2007 2008 # Use macros to implement exception handling. 2009 2010 self.writestmt("__Try") 2011 self.writeline("{") 2012 self.indent += 1 2013 self.process_statement_node(n.body) 2014 self.indent -= 1 2015 self.writeline("}") 2016 2017 self.in_try_finally = in_try_finally 2018 2019 # Finally clauses handle special exceptions. 2020 2021 self.writeline("__Catch (__tmp_exc)") 2022 self.writeline("{") 2023 self.indent += 1 2024 self.process_statement_node(n.final) 2025 2026 # Introduce an if statement to handle the completion of a try block. 2027 2028 self.process_try_completion() 2029 self.writeline("else __Throw(__tmp_exc);") 2030 2031 self.indent -= 1 2032 self.writeline("}") 2033 print >>self.out 2034 2035 def process_try_completion(self): 2036 2037 "Generate a test for the completion of a try block." 2038 2039 self.writestmt("if (__tmp_exc.completing)") 2040 self.writeline("{") 2041 self.indent += 1 2042 2043 # Do not return anything at the module level. 2044 2045 if self.get_namespace_path() != self.name: 2046 2047 # Only use the normal return statement if no surrounding try blocks 2048 # apply. 2049 2050 if not self.in_try_finally and not self.in_try_except: 2051 self.writeline("if (!__ISNULL(__tmp_exc.arg)) return __tmp_exc.arg;") 2052 else: 2053 self.writeline("if (!__ISNULL(__tmp_exc.arg)) __Throw(__tmp_exc);") 2054 2055 self.indent -= 1 2056 self.writeline("}") 2057 2058 def process_while_node(self, n): 2059 2060 "Process the given while node 'n'." 2061 2062 self.writeline("while (1)") 2063 self.writeline("{") 2064 self.indent += 1 2065 test = self.process_statement_node(n.test) 2066 2067 # Emit the loop termination condition unless "while <true value>" is 2068 # indicated. 2069 2070 if not (isinstance(test, PredefinedConstantRef) and test.value): 2071 2072 # Emit a negated test of the continuation condition. 2073 2074 self.start_if(True, self.make_negation(test)) 2075 if n.else_: 2076 self.process_statement_node(n.else_) 2077 self.writestmt("break;") 2078 self.end_if() 2079 2080 in_conditional = self.in_conditional 2081 self.in_conditional = True 2082 self.process_statement_node(n.body) 2083 self.in_conditional = in_conditional 2084 2085 self.indent -= 1 2086 self.writeline("}") 2087 print >>self.out 2088 2089 # Special variable usage. 2090 2091 def get_temp_path(self): 2092 2093 """ 2094 Return the appropriate namespace path for temporary names in the current 2095 namespace. 2096 """ 2097 2098 if self.in_function: 2099 return self.get_namespace_path() 2100 else: 2101 return self.name 2102 2103 def record_temp(self, name): 2104 2105 """ 2106 Record the use of the temporary 'name' in the current namespace. At the 2107 class or module level, the temporary name is associated with the module, 2108 since the variable will then be allocated in the module's own main 2109 program. 2110 """ 2111 2112 path = self.get_temp_path() 2113 2114 init_item(self.temp_usage, path, list) 2115 self.temp_usage[path].append(name) 2116 2117 def remove_temps(self, names): 2118 2119 """ 2120 Remove 'names' from temporary storage allocations, each instance 2121 removing each request for storage. 2122 """ 2123 2124 path = self.get_temp_path() 2125 2126 for name in names: 2127 if self.uses_temp(path, name): 2128 self.temp_usage[path].remove(name) 2129 2130 def uses_temp(self, path, name): 2131 2132 """ 2133 Return whether the given namespace 'path' employs a temporary variable 2134 with the given 'name'. Note that 'path' should only be a module or a 2135 function or method, not a class. 2136 """ 2137 2138 return self.temp_usage.has_key(path) and name in self.temp_usage[path] 2139 2140 def make_negation(self, expr): 2141 2142 "Return a negated form of 'expr'." 2143 2144 result = NegationResult(expr) 2145 2146 # Negation discards the temporary results of its operand. 2147 2148 temps = expr.discards_temporary() 2149 if temps: 2150 self.remove_temps(temps) 2151 2152 return result 2153 2154 # Output generation. 2155 2156 def start_output(self): 2157 2158 "Write the declarations at the top of each source file." 2159 2160 print >>self.out, """\ 2161 #include "types.h" 2162 #include "exceptions.h" 2163 #include "ops.h" 2164 #include "progconsts.h" 2165 #include "progops.h" 2166 #include "progtypes.h" 2167 #include "main.h" 2168 """ 2169 2170 def start_unit(self): 2171 2172 "Record output within a generated function for later use." 2173 2174 self.out = StringIO() 2175 2176 def end_unit(self): 2177 2178 "Restore the output stream." 2179 2180 out = self.out 2181 self.out = self.out_toplevel 2182 return out 2183 2184 def flush_unit(self, name, out): 2185 2186 "Add declarations and generated code." 2187 2188 self.write_temporaries(name) 2189 print >>self.out 2190 out.seek(0) 2191 self.out.write(out.read()) 2192 2193 def start_module(self): 2194 2195 "Write the start of each module's main function." 2196 2197 print >>self.out, "void __main_%s()" % encode_path(self.name) 2198 print >>self.out, "{" 2199 self.indent += 1 2200 2201 # Define temporary variables, excluded from the module structure itself. 2202 2203 tempnames = [] 2204 2205 for n in self.importer.all_module_attrs[self.name]: 2206 if n.startswith("$t"): 2207 tempnames.append(encode_path(n)) 2208 2209 if tempnames: 2210 tempnames.sort() 2211 self.writeline("__attr %s;" % ", ".join(tempnames)) 2212 2213 self.start_unit() 2214 2215 def end_module(self): 2216 2217 "End each module by closing its main function." 2218 2219 out = self.end_unit() 2220 self.flush_unit(self.name, out) 2221 2222 self.indent -= 1 2223 print >>self.out, "}" 2224 2225 def start_function(self, name): 2226 2227 "Start the function having the given 'name'." 2228 2229 self.indent += 1 2230 2231 self.start_unit() 2232 2233 def end_function(self, name): 2234 2235 "End the function having the given 'name'." 2236 2237 out = self.end_unit() 2238 2239 # Write the signature at the top indentation level. 2240 2241 self.indent -= 1 2242 self.write_parameters(name) 2243 print >>self.out, "{" 2244 2245 # Obtain local names from parameters. 2246 2247 parameters = self.importer.function_parameters[name] 2248 locals = self.importer.function_locals[name].keys() 2249 names = [] 2250 volatile_names = [] 2251 2252 for n in locals: 2253 2254 # Filter out special names and parameters. Note that self is a local 2255 # regardless of whether it originally appeared in the parameters or 2256 # not. 2257 2258 if n.startswith("$l") or n in parameters or n == "self": 2259 continue 2260 if n in self.volatile_locals: 2261 volatile_names.append("%s = __NULL" % encode_path(n)) 2262 else: 2263 names.append("%s = __NULL" % encode_path(n)) 2264 2265 # Emit required local names at the function indentation level. 2266 2267 self.indent += 1 2268 2269 if names: 2270 names.sort() 2271 self.writeline("__attr %s;" % ", ".join(names)) 2272 2273 if volatile_names: 2274 volatile_names.sort() 2275 self.writeline("volatile __attr %s;" % ", ".join(volatile_names)) 2276 2277 self.flush_unit(name, out) 2278 2279 self.indent -= 1 2280 print >>self.out, "}" 2281 print >>self.out 2282 2283 def write_parameters(self, name): 2284 2285 """ 2286 For the function having the given 'name', write definitions of 2287 parameters found in the arguments array. 2288 """ 2289 2290 # Generate any self reference. 2291 2292 l = [] 2293 l.append("__attr __result") 2294 2295 if self.is_method(name): 2296 l.append("__attr self") 2297 else: 2298 l.append("__attr __self") 2299 2300 # Generate aliases for the parameters. 2301 2302 for parameter in self.importer.function_parameters[name]: 2303 l.append("%s__attr %s" % ( 2304 parameter in self.volatile_locals and "volatile " or "", 2305 encode_path(parameter))) 2306 2307 self.writeline("__attr %s(%s)" % ( 2308 encode_function_pointer(name), ", ".join(l))) 2309 2310 def write_temporaries(self, name): 2311 2312 "Write temporary storage employed by 'name'." 2313 2314 # Provide space for the recorded number of temporary variables. 2315 2316 if self.uses_temp(name, "__tmp_targets") and self.max_function_target: 2317 self.writeline("__attr __tmp_targets[%d];" % self.max_function_target) 2318 2319 if self.uses_temp(name, "__tmp_contexts") and self.max_context_index: 2320 self.writeline("__attr __tmp_contexts[%d];" % self.max_context_index) 2321 2322 if self.uses_temp(name, "__tmp_values") and self.max_accessor_index: 2323 self.writeline("__attr __tmp_values[%d];" % self.max_accessor_index) 2324 2325 if self.uses_temp(name, "__tmp_attr_refs") and self.max_attribute_ref_index: 2326 self.writeline("__attr *__tmp_attr_refs[%d];" % self.max_attribute_ref_index) 2327 2328 if self.uses_temp(name, "__tmp_results") and self.max_result_target: 2329 self.writeline("__attr __tmp_results[%d] = {0};" % self.max_result_target) 2330 2331 if self.uses_temp(name, "__tmp_private_context"): 2332 self.writeline("__attr __tmp_private_context;") 2333 if self.uses_temp(name, "__tmp_target_value"): 2334 self.writeline("__attr __tmp_target_value;") 2335 if self.uses_temp(name, "__tmp_result"): 2336 self.writeline("__attr __tmp_result;") 2337 2338 module = self.importer.get_module(self.name) 2339 2340 if name in module.exception_namespaces: 2341 self.writeline("__exc __tmp_exc;") 2342 2343 def start_if(self, first, test_ref): 2344 statement = "%sif" % (not first and "else " or "") 2345 2346 # Consume logical results directly. 2347 2348 if isinstance(test_ref, LogicalResult): 2349 self.writeline("%s %s" % (statement, test_ref.apply_test())) 2350 temps = test_ref.discards_temporary() 2351 if temps: 2352 self.remove_temps(temps) 2353 else: 2354 self.writeline("%s (__BOOL(%s))" % (statement, test_ref)) 2355 2356 self.writeline("{") 2357 self.indent += 1 2358 2359 def end_if(self): 2360 self.indent -= 1 2361 self.writeline("}") 2362 2363 def start_else(self): 2364 self.writeline("else") 2365 self.writeline("{") 2366 self.indent += 1 2367 2368 def end_else(self): 2369 self.indent -= 1 2370 self.writeline("}") 2371 2372 def statement(self, expr): 2373 s = str(expr) 2374 if s: 2375 self.writestmt("%s;" % s) 2376 2377 def statements(self, results): 2378 for result in results: 2379 self.statement(result) 2380 2381 def writeline(self, s): 2382 print >>self.out, "%s%s" % (self.pad(), self.indenttext(s, self.indent + 1)) 2383 2384 def writestmt(self, s): 2385 self.writeline(s) 2386 2387 def write_comment(self, s): 2388 self.writestmt("/* %s */" % s) 2389 2390 def pad(self, extra=0): 2391 return (self.indent + extra) * self.tabstop 2392 2393 def indenttext(self, s, levels): 2394 lines = s.split("\n") 2395 out = [lines[0]] 2396 for line in lines[1:]: 2397 out.append(levels * self.tabstop + line) 2398 if line.endswith("("): 2399 levels += 1 2400 elif line.startswith(")"): 2401 levels -= 1 2402 return "\n".join(out) 2403 2404 # vim: tabstop=4 expandtab shiftwidth=4