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