1 #!/usr/bin/env python 2 3 """ 4 Translate programs. 5 6 Copyright (C) 2015, 2016 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 * 23 from encoders import * 24 from os.path import exists, join 25 from os import makedirs 26 from referencing import Reference 27 import compiler 28 import results 29 30 class Translator(CommonOutput): 31 32 "A program translator." 33 34 def __init__(self, importer, deducer, optimiser, output): 35 self.importer = importer 36 self.deducer = deducer 37 self.optimiser = optimiser 38 self.output = output 39 40 def to_output(self): 41 output = join(self.output, "src") 42 43 if not exists(output): 44 makedirs(output) 45 46 self.check_output() 47 48 for module in self.importer.modules.values(): 49 parts = module.name.split(".") 50 if parts[0] != "native": 51 tm = TranslatedModule(module.name, self.importer, self.deducer, self.optimiser) 52 tm.translate(module.filename, join(output, "%s.c" % module.name)) 53 54 # Classes representing intermediate translation results. 55 56 class TranslationResult: 57 58 "An abstract translation result mix-in." 59 60 def get_accessor_kinds(self): 61 return None 62 63 class ReturnRef(TranslationResult): 64 65 "Indicates usage of a return statement." 66 67 pass 68 69 class Expression(results.Result, TranslationResult): 70 71 "A general expression." 72 73 def __init__(self, s): 74 self.s = s 75 def __str__(self): 76 return self.s 77 def __repr__(self): 78 return "Expression(%r)" % self.s 79 80 class TrResolvedNameRef(results.ResolvedNameRef, TranslationResult): 81 82 "A reference to a name in the translation." 83 84 def __init__(self, name, ref, expr=None, parameter=None): 85 results.ResolvedNameRef.__init__(self, name, ref, expr) 86 self.parameter = parameter 87 88 def __str__(self): 89 90 "Return an output representation of the referenced name." 91 92 # For sources, any identified static origin will be constant and thus 93 # usable directly. For targets, no constant should be assigned and thus 94 # the alias (or any plain name) will be used. 95 96 ref = self.static() 97 origin = ref and self.get_origin() 98 static_name = origin and encode_path(origin) 99 100 # Determine whether a qualified name is involved. 101 102 t = (not self.is_constant_alias() and self.get_name() or self.name).rsplit(".", 1) 103 parent = len(t) > 1 and t[0] or None 104 attrname = t[-1] and encode_path(t[-1]) 105 106 # Assignments. 107 108 if self.expr: 109 110 # Eliminate assignments between constants. 111 112 if ref and isinstance(self.expr, results.ResolvedNameRef) and self.expr.static(): 113 return "" 114 115 # Qualified names must be converted into parent-relative assignments. 116 117 elif parent: 118 return "__store_via_object(&%s, %s, %s)" % ( 119 encode_path(parent), encode_symbol("pos", attrname), self.expr) 120 121 # All other assignments involve the names as they were given. 122 123 else: 124 return "(%s%s) = %s" % (self.parameter and "*" or "", attrname, self.expr) 125 126 # Expressions. 127 128 elif static_name: 129 parent = ref.parent() 130 context = ref.has_kind("<function>") and encode_path(parent) or None 131 return "((__attr) {%s, &%s})" % (context and "&%s" % context or "0", static_name) 132 133 # Qualified names must be converted into parent-relative accesses. 134 135 elif parent: 136 return "__load_via_object(&%s, %s)" % ( 137 encode_path(parent), encode_symbol("pos", attrname)) 138 139 # All other accesses involve the names as they were given. 140 141 else: 142 return "(%s%s)" % (self.parameter and "*" or "", attrname) 143 144 class TrConstantValueRef(results.ConstantValueRef, TranslationResult): 145 146 "A constant value reference in the translation." 147 148 def __str__(self): 149 return encode_literal_constant(self.number) 150 151 class TrLiteralSequenceRef(results.LiteralSequenceRef, TranslationResult): 152 153 "A reference representing a sequence of values." 154 155 def __str__(self): 156 return str(self.node) 157 158 class TrInstanceRef(results.InstanceRef, TranslationResult): 159 160 "A reference representing instantiation of a class." 161 162 def __init__(self, ref, expr): 163 164 """ 165 Initialise the reference with 'ref' indicating the nature of the 166 reference and 'expr' being an expression used to create the instance. 167 """ 168 169 results.InstanceRef.__init__(self, ref) 170 self.expr = expr 171 172 def __str__(self): 173 return self.expr 174 175 def __repr__(self): 176 return "TrResolvedInstanceRef(%r, %r)" % (self.ref, self.expr) 177 178 class AttrResult(Expression, TranslationResult): 179 180 "A translation result for an attribute access." 181 182 def __init__(self, s, refs, accessor_kinds): 183 Expression.__init__(self, s) 184 self.refs = refs 185 self.accessor_kinds = accessor_kinds 186 187 def get_origin(self): 188 return self.refs and len(self.refs) == 1 and first(self.refs).get_origin() 189 190 def has_kind(self, kinds): 191 if not self.refs: 192 return False 193 for ref in self.refs: 194 if ref.has_kind(kinds): 195 return True 196 return False 197 198 def get_accessor_kinds(self): 199 return self.accessor_kinds 200 201 def __repr__(self): 202 return "AttrResult(%r, %r, %r)" % (self.s, self.refs, self.accessor_kinds) 203 204 class PredefinedConstantRef(AttrResult): 205 206 "A predefined constant reference." 207 208 def __init__(self, value, expr=None): 209 self.value = value 210 self.expr = expr 211 212 def __str__(self): 213 214 # Eliminate predefined constant assignments. 215 216 if self.expr: 217 return "" 218 219 # Generate the specific constants. 220 221 if self.value in ("False", "True"): 222 return encode_path("__builtins__.boolean.%s" % self.value) 223 elif self.value == "None": 224 return encode_path("__builtins__.none.%s" % self.value) 225 elif self.value == "NotImplemented": 226 return encode_path("__builtins__.notimplemented.%s" % self.value) 227 else: 228 return self.value 229 230 def __repr__(self): 231 return "PredefinedConstantRef(%r)" % self.value 232 233 class BooleanResult(Expression, TranslationResult): 234 235 "A expression producing a boolean result." 236 237 def __str__(self): 238 return "__builtins___bool_bool(%s)" % self.s 239 240 def __repr__(self): 241 return "BooleanResult(%r)" % self.s 242 243 def make_expression(expr): 244 245 "Make a new expression from the existing 'expr'." 246 247 if isinstance(expr, results.Result): 248 return expr 249 else: 250 return Expression(str(expr)) 251 252 # The actual translation process itself. 253 254 class TranslatedModule(CommonModule): 255 256 "A module translator." 257 258 def __init__(self, name, importer, deducer, optimiser): 259 CommonModule.__init__(self, name, importer) 260 self.deducer = deducer 261 self.optimiser = optimiser 262 263 # Output stream. 264 265 self.out = None 266 self.indent = 0 267 self.tabstop = " " 268 269 # Recorded namespaces. 270 271 self.namespaces = [] 272 self.in_conditional = False 273 274 # Exception raising adjustments. 275 276 self.in_try_finally = False 277 self.in_try_except = False 278 279 # Attribute access and accessor counting. 280 281 self.attr_accesses = {} 282 self.attr_accessors = {} 283 284 def __repr__(self): 285 return "TranslatedModule(%r, %r)" % (self.name, self.importer) 286 287 def translate(self, filename, output_filename): 288 289 """ 290 Parse the file having the given 'filename', writing the translation to 291 the given 'output_filename'. 292 """ 293 294 self.parse_file(filename) 295 296 # Collect function namespaces for separate processing. 297 298 self.record_namespaces(self.astnode) 299 300 # Reset the lambda naming (in order to obtain the same names again) and 301 # translate the program. 302 303 self.reset_lambdas() 304 305 self.out = open(output_filename, "w") 306 try: 307 self.start_output() 308 309 # Process namespaces, writing the translation. 310 311 for path, node in self.namespaces: 312 self.process_namespace(path, node) 313 314 # Process the module namespace including class namespaces. 315 316 self.process_namespace([], self.astnode) 317 318 finally: 319 self.out.close() 320 321 def have_object(self): 322 323 "Return whether a namespace is a recorded object." 324 325 return self.importer.objects.get(self.get_namespace_path()) 326 327 def get_builtin_class(self, name): 328 329 "Return a reference to the actual object providing 'name'." 330 331 # NOTE: This makes assumptions about the __builtins__ structure. 332 333 modname = get_builtin_module(name) 334 typename = get_builtin_type(name) 335 return self.importer.get_object("__builtins__.%s.%s" % (modname, typename)) 336 337 def is_method(self, path): 338 339 "Return whether 'path' is a method." 340 341 class_name, method_name = path.rsplit(".", 1) 342 return self.importer.classes.has_key(class_name) and class_name or None 343 344 def in_method(self): 345 346 "Return whether the current namespace provides a method." 347 348 return self.in_function and self.is_method(self.get_namespace_path()) 349 350 # Namespace recording. 351 352 def record_namespaces(self, node): 353 354 "Process the program structure 'node', recording namespaces." 355 356 for n in node.getChildNodes(): 357 self.record_namespaces_in_node(n) 358 359 def record_namespaces_in_node(self, node): 360 361 "Process the program structure 'node', recording namespaces." 362 363 # Function namespaces within modules, classes and other functions. 364 # Functions appearing within conditional statements are given arbitrary 365 # names. 366 367 if isinstance(node, compiler.ast.Function): 368 self.record_function_node(node, (self.in_conditional or self.in_function) and self.get_lambda_name() or node.name) 369 370 elif isinstance(node, compiler.ast.Lambda): 371 self.record_function_node(node, self.get_lambda_name()) 372 373 # Classes are visited, but may be ignored if inside functions. 374 375 elif isinstance(node, compiler.ast.Class): 376 self.enter_namespace(node.name) 377 if self.have_object(): 378 self.record_namespaces(node) 379 self.exit_namespace() 380 381 # Conditional nodes are tracked so that function definitions may be 382 # handled. Since "for" loops are converted to "while" loops, they are 383 # included here. 384 385 elif isinstance(node, (compiler.ast.For, compiler.ast.If, compiler.ast.While)): 386 in_conditional = self.in_conditional 387 self.in_conditional = True 388 self.record_namespaces(node) 389 self.in_conditional = in_conditional 390 391 # All other nodes are processed depth-first. 392 393 else: 394 self.record_namespaces(node) 395 396 def record_function_node(self, n, name): 397 398 """ 399 Record the given function, lambda, if expression or list comprehension 400 node 'n' with the given 'name'. 401 """ 402 403 self.in_function = True 404 self.enter_namespace(name) 405 406 if self.have_object(): 407 408 # Record the namespace path and the node itself. 409 410 self.namespaces.append((self.namespace_path[:], n)) 411 self.record_namespaces_in_node(n.code) 412 413 self.exit_namespace() 414 self.in_function = False 415 416 # Constant referencing. 417 418 def get_literal_instance(self, n, name=None): 419 420 """ 421 For node 'n', return a reference for the type of the given 'name', or if 422 'name' is not specified, deduce the type from the value. 423 """ 424 425 # Handle stray None constants (Sliceobj seems to produce them). 426 427 if name is None and n.value is None: 428 return self.process_name_node(compiler.ast.Name("None")) 429 430 if name in ("dict", "list", "tuple"): 431 ref = self.get_builtin_class(name) 432 return self.process_literal_sequence_node(n, name, ref, TrLiteralSequenceRef) 433 else: 434 value, typename, encoding = self.get_constant_value(n.value, n.literal) 435 name = get_builtin_type(typename) 436 ref = self.get_builtin_class(name) 437 value_type = ref.get_origin() 438 439 path = self.get_namespace_path() 440 441 # Obtain the local numbering of the constant and thus the 442 # locally-qualified name. 443 444 local_number = self.importer.all_constants[path][(value, value_type, encoding)] 445 constant_name = "$c%d" % local_number 446 objpath = self.get_object_path(constant_name) 447 448 # Obtain the unique identifier for the constant. 449 450 number = self.optimiser.constant_numbers[objpath] 451 return TrConstantValueRef(constant_name, ref.instance_of(), value, number) 452 453 # Namespace translation. 454 455 def process_namespace(self, path, node): 456 457 """ 458 Process the namespace for the given 'path' defined by the given 'node'. 459 """ 460 461 self.namespace_path = path 462 463 if isinstance(node, (compiler.ast.Function, compiler.ast.Lambda)): 464 self.in_function = True 465 self.process_function_body_node(node) 466 else: 467 self.in_function = False 468 self.function_target = 0 469 self.start_module() 470 self.process_structure(node) 471 self.end_module() 472 473 def process_structure(self, node): 474 475 "Process the given 'node' or result." 476 477 # Handle processing requests on results. 478 479 if isinstance(node, results.Result): 480 return node 481 482 # Handle processing requests on nodes. 483 484 else: 485 l = CommonModule.process_structure(self, node) 486 487 # Return indications of return statement usage. 488 489 if l and isinstance(l[-1], ReturnRef): 490 return l[-1] 491 else: 492 return None 493 494 def process_structure_node(self, n): 495 496 "Process the individual node 'n'." 497 498 # Plain statements emit their expressions. 499 500 if isinstance(n, compiler.ast.Discard): 501 expr = self.process_structure_node(n.expr) 502 self.statement(expr) 503 504 # Module import declarations. 505 506 elif isinstance(n, compiler.ast.From): 507 self.process_from_node(n) 508 509 # Nodes using operator module functions. 510 511 elif isinstance(n, compiler.ast.Operator): 512 return self.process_operator_node(n) 513 514 elif isinstance(n, compiler.ast.AugAssign): 515 self.process_augassign_node(n) 516 517 elif isinstance(n, compiler.ast.Compare): 518 return self.process_compare_node(n) 519 520 elif isinstance(n, compiler.ast.Slice): 521 return self.process_slice_node(n) 522 523 elif isinstance(n, compiler.ast.Sliceobj): 524 return self.process_sliceobj_node(n) 525 526 elif isinstance(n, compiler.ast.Subscript): 527 return self.process_subscript_node(n) 528 529 # Classes are visited, but may be ignored if inside functions. 530 531 elif isinstance(n, compiler.ast.Class): 532 self.process_class_node(n) 533 534 # Functions within namespaces have any dynamic defaults initialised. 535 536 elif isinstance(n, compiler.ast.Function): 537 self.process_function_node(n) 538 539 # Lambdas are replaced with references to separately-generated 540 # functions. 541 542 elif isinstance(n, compiler.ast.Lambda): 543 return self.process_lambda_node(n) 544 545 # Assignments. 546 547 elif isinstance(n, compiler.ast.Assign): 548 549 # Handle each assignment node. 550 551 for node in n.nodes: 552 self.process_assignment_node(node, n.expr) 553 554 # Accesses. 555 556 elif isinstance(n, compiler.ast.Getattr): 557 return self.process_attribute_access(n) 558 559 # Names. 560 561 elif isinstance(n, compiler.ast.Name): 562 return self.process_name_node(n) 563 564 # Loops and conditionals. 565 566 elif isinstance(n, compiler.ast.For): 567 self.process_for_node(n) 568 569 elif isinstance(n, compiler.ast.While): 570 self.process_while_node(n) 571 572 elif isinstance(n, compiler.ast.If): 573 self.process_if_node(n) 574 575 elif isinstance(n, (compiler.ast.And, compiler.ast.Or)): 576 return self.process_logical_node(n) 577 578 elif isinstance(n, compiler.ast.Not): 579 return self.process_not_node(n) 580 581 # Exception control-flow tracking. 582 583 elif isinstance(n, compiler.ast.TryExcept): 584 self.process_try_node(n) 585 586 elif isinstance(n, compiler.ast.TryFinally): 587 self.process_try_finally_node(n) 588 589 # Control-flow modification statements. 590 591 elif isinstance(n, compiler.ast.Break): 592 self.writestmt("break;") 593 594 elif isinstance(n, compiler.ast.Continue): 595 self.writestmt("continue;") 596 597 elif isinstance(n, compiler.ast.Raise): 598 self.process_raise_node(n) 599 600 elif isinstance(n, compiler.ast.Return): 601 return self.process_return_node(n) 602 603 # Print statements. 604 605 elif isinstance(n, (compiler.ast.Print, compiler.ast.Printnl)): 606 self.statement(self.process_print_node(n)) 607 608 # Invocations. 609 610 elif isinstance(n, compiler.ast.CallFunc): 611 return self.process_invocation_node(n) 612 613 elif isinstance(n, compiler.ast.Keyword): 614 return self.process_structure_node(n.expr) 615 616 # Constant usage. 617 618 elif isinstance(n, compiler.ast.Const): 619 return self.get_literal_instance(n) 620 621 elif isinstance(n, compiler.ast.Dict): 622 return self.get_literal_instance(n, "dict") 623 624 elif isinstance(n, compiler.ast.List): 625 return self.get_literal_instance(n, "list") 626 627 elif isinstance(n, compiler.ast.Tuple): 628 return self.get_literal_instance(n, "tuple") 629 630 # All other nodes are processed depth-first. 631 632 else: 633 return self.process_structure(n) 634 635 def process_assignment_node(self, n, expr): 636 637 "Process the individual node 'n' to be assigned the contents of 'expr'." 638 639 # Names and attributes are assigned the entire expression. 640 641 if isinstance(n, compiler.ast.AssName): 642 name_ref = self.process_name_node(n, self.process_structure_node(expr)) 643 self.statement(name_ref) 644 645 # Employ guards after assignments if required. 646 647 if expr and name_ref.is_name(): 648 self.generate_guard(name_ref.name) 649 650 elif isinstance(n, compiler.ast.AssAttr): 651 in_assignment = self.in_assignment 652 self.in_assignment = self.process_structure_node(expr) 653 self.statement(self.process_attribute_access(n)) 654 self.in_assignment = in_assignment 655 656 # Lists and tuples are matched against the expression and their 657 # items assigned to expression items. 658 659 elif isinstance(n, (compiler.ast.AssList, compiler.ast.AssTuple)): 660 self.process_assignment_node_items(n, expr) 661 662 # Slices and subscripts are permitted within assignment nodes. 663 664 elif isinstance(n, compiler.ast.Slice): 665 self.statement(self.process_slice_node(n, expr)) 666 667 elif isinstance(n, compiler.ast.Subscript): 668 self.statement(self.process_subscript_node(n, expr)) 669 670 def process_attribute_access(self, n): 671 672 "Process the given attribute access node 'n'." 673 674 # Obtain any completed chain and return the reference to it. 675 676 attr_expr = self.process_attribute_chain(n) 677 if self.have_access_expression(n): 678 return attr_expr 679 680 # Where the start of the chain of attributes has been reached, process 681 # the complete access. 682 683 name_ref = attr_expr and attr_expr.is_name() and attr_expr 684 name = name_ref and self.get_name_for_tracking(name_ref.name, name_ref and name_ref.final()) or None 685 686 location = self.get_access_location(name) 687 refs = self.get_referenced_attributes(location) 688 689 # Generate access instructions. 690 691 subs = { 692 "<expr>" : str(attr_expr), 693 "<assexpr>" : str(self.in_assignment), 694 "<context>" : "__tmp_context", 695 "<accessor>" : "__tmp_value", 696 "<target_accessor>" : "__tmp_target_value", 697 } 698 699 output = [] 700 701 for instruction in self.optimiser.access_instructions[location]: 702 output.append(encode_access_instruction(instruction, subs)) 703 704 if len(output) == 1: 705 out = output[0] 706 else: 707 out = "(\n%s\n)" % ",\n".join(output) 708 709 del self.attrs[0] 710 return AttrResult(out, refs, self.get_accessor_kinds(location)) 711 712 def get_referenced_attributes(self, location): 713 714 """ 715 Convert 'location' to the form used by the deducer and retrieve any 716 identified attribute. 717 """ 718 719 access_location = self.deducer.const_accesses.get(location) 720 refs = [] 721 for attrtype, objpath, attr in self.deducer.referenced_attrs[access_location or location]: 722 refs.append(attr) 723 return refs 724 725 def get_accessor_kinds(self, location): 726 727 "Return the accessor kinds for 'location'." 728 729 return self.optimiser.accessor_kinds[location] 730 731 def get_access_location(self, name): 732 733 """ 734 Using the current namespace and the given 'name', return the access 735 location. 736 """ 737 738 path = self.get_path_for_access() 739 740 # Get the location used by the deducer and optimiser and find any 741 # recorded access. 742 743 attrnames = ".".join(self.attrs) 744 access_number = self.get_access_number(path, name, attrnames) 745 self.update_access_number(path, name, attrnames) 746 return (path, name, attrnames, access_number) 747 748 def get_access_number(self, path, name, attrnames): 749 access = name, attrnames 750 if self.attr_accesses.has_key(path) and self.attr_accesses[path].has_key(access): 751 return self.attr_accesses[path][access] 752 else: 753 return 0 754 755 def update_access_number(self, path, name, attrnames): 756 access = name, attrnames 757 if name: 758 init_item(self.attr_accesses, path, dict) 759 init_item(self.attr_accesses[path], access, lambda: 0) 760 self.attr_accesses[path][access] += 1 761 762 def get_accessor_location(self, name): 763 764 """ 765 Using the current namespace and the given 'name', return the accessor 766 location. 767 """ 768 769 path = self.get_path_for_access() 770 771 # Get the location used by the deducer and optimiser and find any 772 # recorded accessor. 773 774 access_number = self.get_accessor_number(path, name) 775 self.update_accessor_number(path, name) 776 return (path, name, None, access_number) 777 778 def get_accessor_number(self, path, name): 779 if self.attr_accessors.has_key(path) and self.attr_accessors[path].has_key(name): 780 return self.attr_accessors[path][name] 781 else: 782 return 0 783 784 def update_accessor_number(self, path, name): 785 if name: 786 init_item(self.attr_accessors, path, dict) 787 init_item(self.attr_accessors[path], name, lambda: 0) 788 self.attr_accessors[path][name] += 1 789 790 def process_class_node(self, n): 791 792 "Process the given class node 'n'." 793 794 class_name = self.get_object_path(n.name) 795 796 # Where a class is set conditionally or where the name may refer to 797 # different values, assign the name. 798 799 ref = self.importer.identify(class_name) 800 801 if not ref.static(): 802 self.process_assignment_for_object( 803 n.name, make_expression("((__attr) {0, &%s})" % 804 encode_path(class_name))) 805 806 self.enter_namespace(n.name) 807 808 if self.have_object(): 809 self.write_comment("Class: %s" % class_name) 810 811 self.initialise_inherited_members(class_name) 812 813 self.process_structure(n) 814 self.write_comment("End class: %s" % class_name) 815 816 self.exit_namespace() 817 818 def initialise_inherited_members(self, class_name): 819 820 "Initialise members of 'class_name' inherited from its ancestors." 821 822 for name, path in self.importer.all_class_attrs[class_name].items(): 823 target = "%s.%s" % (class_name, name) 824 825 # Ignore attributes with definitions. 826 827 ref = self.importer.identify(target) 828 if ref: 829 continue 830 831 # Ignore special type attributes. 832 833 if is_type_attribute(name): 834 continue 835 836 # Reference inherited attributes. 837 838 ref = self.importer.identify(path) 839 if ref and not ref.static(): 840 parent, attrname = path.rsplit(".", 1) 841 842 self.writestmt("__store_via_object(&%s, %s, __load_via_object(&%s, %s));" % ( 843 encode_path(class_name), encode_symbol("pos", name), 844 encode_path(parent), encode_symbol("pos", attrname) 845 )) 846 847 def process_from_node(self, n): 848 849 "Process the given node 'n', importing from another module." 850 851 path = self.get_namespace_path() 852 853 # Attempt to obtain the referenced objects. 854 855 for name, alias in n.names: 856 if name == "*": 857 raise InspectError("Only explicitly specified names can be imported from modules.", path, n) 858 859 # Obtain the path of the assigned name. 860 861 objpath = self.get_object_path(alias or name) 862 863 # Obtain the identity of the name. 864 865 ref = self.importer.identify(objpath) 866 867 # Where the name is not static, assign the value. 868 869 if ref and not ref.static() and ref.get_name(): 870 self.writestmt("%s;" % 871 TrResolvedNameRef(alias or name, Reference("<var>", None, objpath), 872 expr=TrResolvedNameRef(name, ref))) 873 874 def process_function_body_node(self, n): 875 876 """ 877 Process the given function, lambda, if expression or list comprehension 878 node 'n', generating the body. 879 """ 880 881 function_name = self.get_namespace_path() 882 self.start_function(function_name) 883 884 # Process the function body. 885 886 in_conditional = self.in_conditional 887 self.in_conditional = False 888 self.function_target = 0 889 890 # Process any guards defined for the parameters. 891 892 for name in self.importer.function_parameters.get(function_name): 893 self.generate_guard(name) 894 895 # Produce the body and any additional return statement. 896 897 expr = self.process_structure_node(n.code) or PredefinedConstantRef("None") 898 if not isinstance(expr, ReturnRef): 899 self.writestmt("return %s;" % expr) 900 901 self.in_conditional = in_conditional 902 903 self.end_function(function_name) 904 905 def generate_guard(self, name): 906 907 """ 908 Get the accessor details for 'name', found in the current namespace, and 909 generate any guards defined for it. 910 """ 911 912 # Obtain the location, keeping track of assignment versions. 913 914 location = self.get_accessor_location(name) 915 test = self.deducer.accessor_guard_tests.get(location) 916 917 # Generate any guard from the deduced information. 918 919 if test: 920 guard, guard_type = test 921 922 if guard == "specific": 923 ref = first(self.deducer.accessor_all_types[location]) 924 argstr = "&%s" % encode_path(ref.get_origin()) 925 elif guard == "common": 926 ref = first(self.deducer.accessor_all_general_types[location]) 927 typeattr = encode_type_attribute(ref.get_origin()) 928 argstr = "%s, %s" % (encode_symbol("pos", typeattr), encode_symbol("code", typeattr)) 929 else: 930 return 931 932 # Produce an appropriate access to an attribute's value. 933 934 parameters = self.importer.function_parameters.get(self.get_namespace_path()) 935 if parameters and name in parameters: 936 name_to_value = "%s->value" % name 937 else: 938 name_to_value = "%s.value" % name 939 940 # Write a test that raises a TypeError upon failure. 941 942 self.writestmt("if (!__test_%s_%s(%s, %s)) __raise_type_error();" % ( 943 guard, guard_type, name_to_value, argstr)) 944 945 def process_function_node(self, n): 946 947 """ 948 Process the given function, lambda, if expression or list comprehension 949 node 'n', generating any initialisation statements. 950 """ 951 952 # Where a function is declared conditionally, use a separate name for 953 # the definition, and assign the definition to the stated name. 954 955 original_name = n.name 956 957 if self.in_conditional or self.in_function: 958 name = self.get_lambda_name() 959 else: 960 name = n.name 961 962 objpath = self.get_object_path(name) 963 964 # Obtain details of the defaults. 965 966 defaults = self.process_function_defaults(n, name, objpath) 967 if defaults: 968 for default in defaults: 969 self.writeline("%s;" % default) 970 971 # Where a function is set conditionally or where the name may refer to 972 # different values, assign the name. 973 974 ref = self.importer.identify(objpath) 975 976 if self.in_conditional or self.in_function: 977 self.process_assignment_for_object(original_name, compiler.ast.Name(name)) 978 elif not ref.static(): 979 context = self.is_method(objpath) 980 981 self.process_assignment_for_object(original_name, 982 make_expression("((__attr) {%s, &%s})" % ( 983 context and "&%s" % encode_path(context) or "0", 984 encode_path(objpath)))) 985 986 def process_function_defaults(self, n, name, objpath, instance_name=None): 987 988 """ 989 Process the given function or lambda node 'n', initialising defaults 990 that are dynamically set. The given 'name' indicates the name of the 991 function. The given 'objpath' indicates the origin of the function. 992 The given 'instance_name' indicates the name of any separate instance 993 of the function created to hold the defaults. 994 995 Return a list of operations setting defaults on a function instance. 996 """ 997 998 function_name = self.get_object_path(name) 999 function_defaults = self.importer.function_defaults.get(function_name) 1000 if not function_defaults: 1001 return None 1002 1003 # Determine whether any unidentified defaults are involved. 1004 1005 for argname, default in function_defaults: 1006 if not default.static(): 1007 break 1008 else: 1009 return None 1010 1011 # Handle bound methods. 1012 1013 if not instance_name: 1014 if self.is_method(objpath): 1015 instance_name = "&%s" % encode_bound_reference(objpath) 1016 else: 1017 instance_name = "&%s" % encode_path(objpath) 1018 1019 # Where defaults are involved but cannot be identified, obtain a new 1020 # instance of the lambda and populate the defaults. 1021 1022 defaults = [] 1023 1024 # Join the original defaults with the inspected defaults. 1025 1026 original_defaults = [(argname, default) for (argname, default) in compiler.ast.get_defaults(n) if default] 1027 1028 for i, (original, inspected) in enumerate(map(None, original_defaults, function_defaults)): 1029 1030 # Obtain any reference for the default. 1031 1032 if original: 1033 argname, default = original 1034 name_ref = self.process_structure_node(default) 1035 elif inspected: 1036 argname, default = inspected 1037 name_ref = TrResolvedNameRef(argname, default) 1038 else: 1039 continue 1040 1041 # Generate default initialisers except when constants are employed. 1042 # Constants should be used when populating the function structures. 1043 1044 if name_ref and not isinstance(name_ref, TrConstantValueRef): 1045 defaults.append("__SETDEFAULT(%s, %s, %s)" % (instance_name, i, name_ref)) 1046 1047 return defaults 1048 1049 def process_if_node(self, n): 1050 1051 """ 1052 Process the given "if" node 'n'. 1053 """ 1054 1055 first = True 1056 for test, body in n.tests: 1057 test_ref = self.process_structure_node(test) 1058 self.start_if(first, test_ref) 1059 1060 in_conditional = self.in_conditional 1061 self.in_conditional = True 1062 self.process_structure_node(body) 1063 self.in_conditional = in_conditional 1064 1065 self.end_if() 1066 first = False 1067 1068 if n.else_: 1069 self.start_else() 1070 self.process_structure_node(n.else_) 1071 self.end_else() 1072 1073 def process_invocation_node(self, n): 1074 1075 "Process the given invocation node 'n'." 1076 1077 expr = self.process_structure_node(n.node) 1078 objpath = expr.get_origin() 1079 target = None 1080 target_structure = None 1081 function = None 1082 instantiation = False 1083 literal_instantiation = False 1084 context_required = True 1085 1086 # Obtain details of the callable. 1087 1088 # Literals may be instantiated specially. 1089 1090 if expr.is_name() and expr.name.startswith("$L") and objpath: 1091 instantiation = literal_instantiation = objpath 1092 parameters = None 1093 target = encode_literal_instantiator(objpath) 1094 context_required = False 1095 1096 # Identified targets employ function pointers directly. 1097 1098 elif objpath: 1099 parameters = self.importer.function_parameters.get(objpath) 1100 1101 # Class invocation involves instantiators. 1102 1103 if expr.has_kind("<class>"): 1104 instantiation = objpath 1105 target = encode_instantiator_pointer(objpath) 1106 target_structure = "&%s" % encode_bound_reference("%s.__init__" % objpath) 1107 context_required = False 1108 1109 # Only plain functions and bound methods employ function pointers. 1110 1111 elif expr.has_kind("<function>"): 1112 function = objpath 1113 1114 # Test for functions and methods. 1115 1116 context_required = self.is_method(objpath) 1117 accessor_kinds = expr.get_accessor_kinds() 1118 instance_accessor = accessor_kinds and \ 1119 len(accessor_kinds) == 1 and \ 1120 first(accessor_kinds) == "<instance>" 1121 1122 # Only identify certain bound methods or functions. 1123 1124 if not context_required or instance_accessor: 1125 target = encode_function_pointer(objpath) 1126 1127 # Access bound method defaults even if it is not clear whether 1128 # the accessor is appropriate. 1129 1130 target_structure = self.is_method(objpath) and \ 1131 "&%s" % encode_bound_reference(objpath) or \ 1132 "&%s" % encode_path(objpath) 1133 1134 # Other targets are retrieved at run-time. 1135 1136 else: 1137 parameters = None 1138 1139 # Arguments are presented in a temporary frame array with any context 1140 # always being the first argument. Where it would be unused, it may be 1141 # set to null. 1142 1143 if context_required: 1144 args = ["__CONTEXT_AS_VALUE(__tmp_targets[%d])" % self.function_target] 1145 else: 1146 args = ["(__attr) {0, 0}"] 1147 1148 args += [None] * (not parameters and len(n.args) or parameters and len(parameters) or 0) 1149 kwcodes = [] 1150 kwargs = [] 1151 1152 # Any invocations in the arguments will store target details in a 1153 # different location. 1154 1155 self.function_target += 1 1156 1157 for i, arg in enumerate(n.args): 1158 argexpr = self.process_structure_node(arg) 1159 1160 # Store a keyword argument, either in the argument list or 1161 # in a separate keyword argument list for subsequent lookup. 1162 1163 if isinstance(arg, compiler.ast.Keyword): 1164 1165 # With knowledge of the target, store the keyword 1166 # argument directly. 1167 1168 if parameters: 1169 try: 1170 argnum = parameters.index(arg.name) 1171 except ValueError: 1172 raise TranslateError("Argument %s is not recognised." % arg.name, 1173 self.get_namespace_path(), n) 1174 args[argnum+1] = str(argexpr) 1175 1176 # Otherwise, store the details in a separate collection. 1177 1178 else: 1179 kwargs.append(str(argexpr)) 1180 kwcodes.append("{%s, %s}" % ( 1181 encode_symbol("ppos", arg.name), 1182 encode_symbol("pcode", arg.name))) 1183 1184 # Store non-keyword arguments in the argument list, rejecting 1185 # superfluous arguments. 1186 1187 else: 1188 try: 1189 args[i+1] = str(argexpr) 1190 except IndexError: 1191 raise TranslateError("Too many arguments specified.", 1192 self.get_namespace_path(), n) 1193 1194 # Reference the current target again. 1195 1196 self.function_target -= 1 1197 1198 # Defaults are added to the frame where arguments are missing. 1199 1200 if parameters: 1201 function_defaults = self.importer.function_defaults.get(objpath) 1202 if function_defaults: 1203 1204 # Visit each default and set any missing arguments. 1205 # Use the target structure to obtain defaults, as opposed to the 1206 # actual function involved. 1207 1208 for i, (argname, default) in enumerate(function_defaults): 1209 argnum = parameters.index(argname) 1210 if not args[argnum+1]: 1211 args[argnum+1] = "__GETDEFAULT(%s, %d)" % (target_structure, i) 1212 1213 # Test for missing arguments. 1214 1215 if None in args: 1216 raise TranslateError("Not all arguments supplied.", 1217 self.get_namespace_path(), n) 1218 1219 # Encode the arguments. 1220 1221 argstr = "__ARGS(%s)" % ", ".join(args) 1222 kwargstr = kwargs and ("__ARGS(%s)" % ", ".join(kwargs)) or "0" 1223 kwcodestr = kwcodes and ("__KWARGS(%s)" % ", ".join(kwcodes)) or "0" 1224 1225 # Where literal instantiation is occurring, add an argument indicating 1226 # the number of values. 1227 1228 if literal_instantiation: 1229 argstr += ", %d" % (len(args) - 1) 1230 1231 # First, the invocation expression is presented. 1232 1233 stages = [] 1234 1235 # Without a known specific callable, the expression provides the target. 1236 1237 if not target or context_required: 1238 stages.append("__tmp_targets[%d] = %s" % (self.function_target, expr)) 1239 1240 # Any specific callable is then obtained. 1241 1242 if target: 1243 stages.append(target) 1244 elif function: 1245 stages.append("__load_via_object(__tmp_targets[%d].value, %s).fn" % ( 1246 self.function_target, encode_symbol("pos", "__fn__"))) 1247 1248 # With a known target, the function is obtained directly and called. 1249 1250 if target or function: 1251 output = "(\n%s\n)(%s)" % (",\n".join(stages), argstr) 1252 1253 # With unknown targets, the generic invocation function is applied to 1254 # the callable and argument collections. 1255 1256 else: 1257 output = "(%s, __invoke(\n__tmp_targets[%d],\n%d, %d, %s, %s,\n%d, %s\n))" % ( 1258 ",\n".join(stages), 1259 self.function_target, 1260 self.always_callable and 1 or 0, 1261 len(kwargs), kwcodestr, kwargstr, 1262 len(args), argstr) 1263 1264 if instantiation: 1265 return TrInstanceRef(instantiation, output) 1266 else: 1267 return make_expression(output) 1268 1269 def always_callable(self, refs): 1270 1271 "Determine whether all 'refs' are callable." 1272 1273 for ref in refs: 1274 if not ref.static(): 1275 return False 1276 else: 1277 origin = ref.final() 1278 if not self.importer.get_attribute(origin, "__fn__"): 1279 return False 1280 return True 1281 1282 def need_default_arguments(self, objpath, nargs): 1283 1284 """ 1285 Return whether any default arguments are needed when invoking the object 1286 given by 'objpath'. 1287 """ 1288 1289 parameters = self.importer.function_parameters.get(objpath) 1290 return nargs < len(parameters) 1291 1292 def process_lambda_node(self, n): 1293 1294 "Process the given lambda node 'n'." 1295 1296 name = self.get_lambda_name() 1297 function_name = self.get_object_path(name) 1298 1299 defaults = self.process_function_defaults(n, name, function_name, "__tmp_value") 1300 1301 # Without defaults, produce an attribute referring to the function. 1302 1303 if not defaults: 1304 return make_expression("((__attr) {0, &%s})" % encode_path(function_name)) 1305 1306 # With defaults, copy the function structure and set the defaults on the 1307 # copy. 1308 1309 else: 1310 return make_expression("(__tmp_value = __COPY(&%s, sizeof(%s)), %s, (__attr) {0, __tmp_value})" % ( 1311 encode_path(function_name), 1312 encode_symbol("obj", function_name), 1313 ", ".join(defaults))) 1314 1315 def process_logical_node(self, n): 1316 1317 """ 1318 Process the given operator node 'n'. 1319 1320 Convert ... to ... 1321 1322 <a> and <b> 1323 (__tmp_result = <a>, !__BOOL(__tmp_result)) ? __tmp_result : <b> 1324 1325 <a> or <b> 1326 (__tmp_result = <a>, __BOOL(__tmp_result)) ? __tmp_result : <b> 1327 """ 1328 1329 if isinstance(n, compiler.ast.And): 1330 op = "!" 1331 else: 1332 op = "" 1333 1334 results = [] 1335 1336 for node in n.nodes[:-1]: 1337 expr = self.process_structure_node(node) 1338 results.append("(__tmp_result = %s, %s__BOOL(__tmp_result)) ? __tmp_result : " % (expr, op)) 1339 1340 expr = self.process_structure_node(n.nodes[-1]) 1341 results.append(str(expr)) 1342 1343 return make_expression("(%s)" % "".join(results)) 1344 1345 def process_name_node(self, n, expr=None): 1346 1347 "Process the given name node 'n' with the optional assignment 'expr'." 1348 1349 # Determine whether the name refers to a static external entity. 1350 1351 if n.name in predefined_constants: 1352 return PredefinedConstantRef(n.name, expr) 1353 1354 # Convert literal references, operator function names, and print 1355 # function names to references. 1356 1357 elif n.name.startswith("$L") or n.name.startswith("$op") or \ 1358 n.name.startswith("$print"): 1359 ref = self.importer.get_module(self.name).special.get(n.name) 1360 return TrResolvedNameRef(n.name, ref) 1361 1362 # Get the appropriate name for the name reference, using the same method 1363 # as in the inspector. 1364 1365 path = self.get_namespace_path() 1366 objpath = self.get_object_path(n.name) 1367 1368 # Determine any assigned globals. 1369 1370 globals = self.importer.get_module(self.name).scope_globals.get(path) 1371 if globals and n.name in globals: 1372 objpath = self.get_global_path(n.name) 1373 1374 # Get the static identity of the name. 1375 1376 ref = self.importer.identify(objpath) 1377 if ref and not ref.get_name(): 1378 ref = ref.alias(objpath) 1379 1380 # Obtain any resolved names for non-assignment names. 1381 1382 if not expr and not ref and self.in_function: 1383 locals = self.importer.function_locals.get(path) 1384 ref = locals and locals.get(n.name) 1385 1386 # Determine whether the name refers to a parameter. The generation of 1387 # parameter references is different from other names. 1388 1389 parameters = self.importer.function_parameters.get(path) 1390 parameter = n.name == "self" and self.in_method() or \ 1391 parameters and n.name in parameters 1392 1393 # Qualified names are used for resolved static references or for 1394 # static namespace members. The reference should be configured to return 1395 # such names. 1396 1397 return TrResolvedNameRef(n.name, ref, expr=expr, parameter=parameter) 1398 1399 def process_not_node(self, n): 1400 1401 "Process the given operator node 'n'." 1402 1403 return make_expression("(__BOOL(%s) ? %s : %s)" % 1404 (self.process_structure_node(n.expr), PredefinedConstantRef("False"), 1405 PredefinedConstantRef("True"))) 1406 1407 def process_raise_node(self, n): 1408 1409 "Process the given raise node 'n'." 1410 1411 # NOTE: Determine which raise statement variants should be permitted. 1412 1413 if n.expr1: 1414 exc = self.process_structure_node(n.expr1) 1415 1416 # Raise instances, testing the kind at run-time if necessary and 1417 # instantiating any non-instance. 1418 1419 if isinstance(exc, TrInstanceRef): 1420 self.writestmt("__Raise(%s);" % exc) 1421 else: 1422 self.writestmt("__Raise(__ensure_instance(%s));" % exc) 1423 else: 1424 self.writestmt("__Throw(__tmp_exc);") 1425 1426 def process_return_node(self, n): 1427 1428 "Process the given return node 'n'." 1429 1430 expr = self.process_structure_node(n.value) or PredefinedConstantRef("None") 1431 if self.in_try_finally or self.in_try_except: 1432 self.writestmt("__Return(%s);" % expr) 1433 else: 1434 self.writestmt("return %s;" % expr) 1435 1436 return ReturnRef() 1437 1438 def process_try_node(self, n): 1439 1440 """ 1441 Process the given "try...except" node 'n'. 1442 """ 1443 1444 in_try_except = self.in_try_except 1445 self.in_try_except = True 1446 1447 # Use macros to implement exception handling. 1448 1449 self.writestmt("__Try") 1450 self.writeline("{") 1451 self.indent += 1 1452 self.process_structure_node(n.body) 1453 1454 # Put the else statement in another try block that handles any raised 1455 # exceptions and converts them to exceptions that will not be handled by 1456 # the main handling block. 1457 1458 if n.else_: 1459 self.writestmt("__Try") 1460 self.writeline("{") 1461 self.indent += 1 1462 self.process_structure_node(n.else_) 1463 self.indent -= 1 1464 self.writeline("}") 1465 self.writeline("__Catch (__tmp_exc)") 1466 self.writeline("{") 1467 self.indent += 1 1468 self.writeline("if (__tmp_exc.raising) __RaiseElse(__tmp_exc.arg);") 1469 self.writeline("else if (__tmp_exc.completing) __Throw(__tmp_exc);") 1470 self.indent -= 1 1471 self.writeline("}") 1472 1473 # Complete the try block and enter the finally block, if appropriate. 1474 1475 if self.in_try_finally: 1476 self.writestmt("__Complete;") 1477 1478 self.indent -= 1 1479 self.writeline("}") 1480 1481 self.in_try_except = in_try_except 1482 1483 # Handlers are tests within a common handler block. 1484 1485 self.writeline("__Catch (__tmp_exc)") 1486 self.writeline("{") 1487 self.indent += 1 1488 1489 # Introduce an if statement to handle the completion of a try block. 1490 1491 self.process_try_completion() 1492 1493 # Handle exceptions in else blocks converted to __RaiseElse, converting 1494 # them back to normal exceptions. 1495 1496 if n.else_: 1497 self.writeline("else if (__tmp_exc.raising_else) __Raise(__tmp_exc.arg);") 1498 1499 # Exception handling. 1500 1501 for name, var, handler in n.handlers: 1502 1503 # Test for specific exceptions. 1504 1505 if name is not None: 1506 name_ref = self.process_structure_node(name) 1507 self.writeline("else if (__BOOL(__fn_native_introspection_isinstance((__attr[]) {{0, 0}, __tmp_exc.arg, %s})))" % name_ref) 1508 else: 1509 self.writeline("else if (1)") 1510 1511 self.writeline("{") 1512 self.indent += 1 1513 1514 # Establish the local for the handler. 1515 1516 if var is not None: 1517 self.writestmt("%s;" % self.process_name_node(var, make_expression("__tmp_exc.arg"))) 1518 1519 if handler is not None: 1520 self.process_structure_node(handler) 1521 1522 self.indent -= 1 1523 self.writeline("}") 1524 1525 # Re-raise unhandled exceptions. 1526 1527 self.writeline("else __Throw(__tmp_exc);") 1528 1529 # End the handler block. 1530 1531 self.indent -= 1 1532 self.writeline("}") 1533 1534 def process_try_finally_node(self, n): 1535 1536 """ 1537 Process the given "try...finally" node 'n'. 1538 """ 1539 1540 in_try_finally = self.in_try_finally 1541 self.in_try_finally = True 1542 1543 # Use macros to implement exception handling. 1544 1545 self.writestmt("__Try") 1546 self.writeline("{") 1547 self.indent += 1 1548 self.process_structure_node(n.body) 1549 self.indent -= 1 1550 self.writeline("}") 1551 1552 self.in_try_finally = in_try_finally 1553 1554 # Finally clauses handle special exceptions. 1555 1556 self.writeline("__Catch (__tmp_exc)") 1557 self.writeline("{") 1558 self.indent += 1 1559 self.process_structure_node(n.final) 1560 1561 # Introduce an if statement to handle the completion of a try block. 1562 1563 self.process_try_completion() 1564 self.writeline("else __Throw(__tmp_exc);") 1565 1566 self.indent -= 1 1567 self.writeline("}") 1568 1569 def process_try_completion(self): 1570 1571 "Generate a test for the completion of a try block." 1572 1573 self.writestmt("if (__tmp_exc.completing)") 1574 self.writeline("{") 1575 self.indent += 1 1576 1577 # Do not return anything at the module level. 1578 1579 if self.get_namespace_path() != self.name: 1580 1581 # Only use the normal return statement if no surrounding try blocks 1582 # apply. 1583 1584 if not self.in_try_finally and not self.in_try_except: 1585 self.writeline("if (!__ISNULL(__tmp_exc.arg)) return __tmp_exc.arg;") 1586 else: 1587 self.writeline("if (!__ISNULL(__tmp_exc.arg)) __Throw(__tmp_exc);") 1588 1589 self.indent -= 1 1590 self.writeline("}") 1591 1592 def process_while_node(self, n): 1593 1594 "Process the given while node 'n'." 1595 1596 self.writeline("while (1)") 1597 self.writeline("{") 1598 self.indent += 1 1599 test = self.process_structure_node(n.test) 1600 1601 # Emit the loop termination condition unless "while <true value>" is 1602 # indicated. 1603 1604 if not (isinstance(test, PredefinedConstantRef) and test.value): 1605 1606 # NOTE: This needs to evaluate whether the operand is true or false 1607 # NOTE: according to Python rules. 1608 1609 self.writeline("if (!__BOOL(%s))" % test) 1610 self.writeline("{") 1611 self.indent += 1 1612 if n.else_: 1613 self.process_structure_node(n.else_) 1614 self.writestmt("break;") 1615 self.indent -= 1 1616 self.writeline("}") 1617 1618 in_conditional = self.in_conditional 1619 self.in_conditional = True 1620 self.process_structure_node(n.body) 1621 self.in_conditional = in_conditional 1622 1623 self.indent -= 1 1624 self.writeline("}") 1625 1626 # Output generation. 1627 1628 def start_output(self): 1629 1630 "Write the declarations at the top of each source file." 1631 1632 print >>self.out, """\ 1633 #include "types.h" 1634 #include "exceptions.h" 1635 #include "ops.h" 1636 #include "progconsts.h" 1637 #include "progops.h" 1638 #include "progtypes.h" 1639 #include "main.h" 1640 """ 1641 1642 def start_module(self): 1643 1644 "Write the start of each module's main function." 1645 1646 print >>self.out, "void __main_%s()" % encode_path(self.name) 1647 print >>self.out, "{" 1648 self.indent += 1 1649 self.write_temporaries(self.importer.function_targets.get(self.name)) 1650 1651 def end_module(self): 1652 1653 "End each module by closing its main function." 1654 1655 self.indent -= 1 1656 print >>self.out, "}" 1657 1658 def start_function(self, name): 1659 1660 "Start the function having the given 'name'." 1661 1662 print >>self.out, "__attr %s(__attr __args[])" % encode_function_pointer(name) 1663 print >>self.out, "{" 1664 self.indent += 1 1665 self.write_temporaries(self.importer.function_targets.get(name)) 1666 1667 # Obtain local names from parameters. 1668 1669 parameters = self.importer.function_parameters[name] 1670 locals = self.importer.function_locals[name].keys() 1671 names = [] 1672 1673 for n in locals: 1674 1675 # Filter out special names and parameters. Note that self is a local 1676 # regardless of whether it originally appeared in the parameters or 1677 # not. 1678 1679 if n.startswith("$l") or n in parameters or n == "self": 1680 continue 1681 names.append(encode_path(n)) 1682 1683 # Emit required local names. 1684 1685 if names: 1686 names.sort() 1687 self.writeline("__attr %s;" % ", ".join(names)) 1688 1689 self.write_parameters(name) 1690 1691 def end_function(self, name): 1692 1693 "End the function having the given 'name'." 1694 1695 self.indent -= 1 1696 print >>self.out, "}" 1697 print >>self.out 1698 1699 def write_temporaries(self, targets): 1700 1701 """ 1702 Write temporary storage employed by functions, providing space for the 1703 given number of 'targets'. 1704 """ 1705 1706 targets = targets is not None and "__tmp_targets[%d], " % targets or "" 1707 1708 self.writeline("__ref __tmp_context, __tmp_value, __tmp_target_value;") 1709 self.writeline("__attr %s__tmp_result;" % targets) 1710 self.writeline("__exc __tmp_exc;") 1711 1712 def write_parameters(self, name): 1713 1714 """ 1715 For the function having the given 'name', write definitions of 1716 parameters found in the arguments array. 1717 """ 1718 1719 parameters = self.importer.function_parameters[name] 1720 1721 # Generate any self reference. 1722 1723 if self.is_method(name): 1724 self.writeline("__attr * const self = &__args[0];") 1725 1726 # Generate aliases for the parameters. 1727 1728 for i, parameter in enumerate(parameters): 1729 self.writeline("__attr * const %s = &__args[%d];" % (encode_path(parameter), i+1)) 1730 1731 def start_if(self, first, test_ref): 1732 self.writestmt("%sif (__BOOL(%s))" % (not first and "else " or "", test_ref)) 1733 self.writeline("{") 1734 self.indent += 1 1735 1736 def end_if(self): 1737 self.indent -= 1 1738 self.writeline("}") 1739 1740 def start_else(self): 1741 self.writeline("else") 1742 self.writeline("{") 1743 self.indent += 1 1744 1745 def end_else(self): 1746 self.indent -= 1 1747 self.writeline("}") 1748 1749 def statement(self, expr): 1750 # NOTE: Should never be None. 1751 if not expr: 1752 self.writestmt("...;") 1753 s = str(expr) 1754 if s: 1755 self.writestmt("%s;" % s) 1756 1757 def statements(self, results): 1758 for result in results: 1759 self.statement(result) 1760 1761 def writeline(self, s): 1762 print >>self.out, "%s%s" % (self.pad(), self.indenttext(s, self.indent + 1)) 1763 1764 def writestmt(self, s): 1765 print >>self.out 1766 self.writeline(s) 1767 1768 def write_comment(self, s): 1769 self.writestmt("/* %s */" % s) 1770 1771 def pad(self, extra=0): 1772 return (self.indent + extra) * self.tabstop 1773 1774 def indenttext(self, s, levels): 1775 lines = s.split("\n") 1776 out = [lines[0]] 1777 for line in lines[1:]: 1778 out.append(levels * self.tabstop + line) 1779 if line.endswith("("): 1780 levels += 1 1781 elif line.startswith(")"): 1782 levels -= 1 1783 return "\n".join(out) 1784 1785 # vim: tabstop=4 expandtab shiftwidth=4