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