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 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, "&%s" % 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 self.process_assignment_for_function(original_name, 894 make_expression("((__attr) {0, &%s})" % encode_path(objpath))) 895 896 def process_function_defaults(self, n, name, instance_name): 897 898 """ 899 Process the given function or lambda node 'n', initialising defaults 900 that are dynamically set. The given 'name' indicates the name of the 901 function. The given 'instance_name' indicates the name of any separate 902 instance of the function created to hold the defaults. 903 904 Return a list of operations setting defaults on a function instance. 905 """ 906 907 function_name = self.get_object_path(name) 908 function_defaults = self.importer.function_defaults.get(function_name) 909 if not function_defaults: 910 return None 911 912 # Determine whether any unidentified defaults are involved. 913 914 need_defaults = [argname for argname, default in function_defaults if default.has_kind("<var>")] 915 if not need_defaults: 916 return None 917 918 # Where defaults are involved but cannot be identified, obtain a new 919 # instance of the lambda and populate the defaults. 920 921 defaults = [] 922 923 # Join the original defaults with the inspected defaults. 924 925 original_defaults = [(argname, default) for (argname, default) in compiler.ast.get_defaults(n) if default] 926 927 for i, (original, inspected) in enumerate(map(None, original_defaults, function_defaults)): 928 929 # Obtain any reference for the default. 930 931 if original: 932 argname, default = original 933 name_ref = self.process_structure_node(default) 934 elif inspected: 935 argname, default = inspected 936 name_ref = TrResolvedNameRef(argname, default) 937 else: 938 continue 939 940 if name_ref: 941 defaults.append("__SETDEFAULT(%s, %s, %s)" % (encode_path(instance_name), i, name_ref)) 942 943 return defaults 944 945 def process_if_node(self, n): 946 947 """ 948 Process the given "if" node 'n'. 949 """ 950 951 first = True 952 for test, body in n.tests: 953 test_ref = self.process_structure_node(test) 954 self.start_if(first, test_ref) 955 956 in_conditional = self.in_conditional 957 self.in_conditional = True 958 self.process_structure_node(body) 959 self.in_conditional = in_conditional 960 961 self.end_if() 962 first = False 963 964 if n.else_: 965 self.start_else() 966 self.process_structure_node(n.else_) 967 self.end_else() 968 969 def process_invocation_node(self, n): 970 971 "Process the given invocation node 'n'." 972 973 expr = self.process_structure_node(n.node) 974 objpath = expr.get_origin() 975 target = None 976 function = None 977 literal_instantiation = False 978 979 # Obtain details of the callable. 980 981 # Literals may be instantiated specially. 982 983 if expr.is_name() and expr.name.startswith("$L") and objpath: 984 literal_instantiation = True 985 parameters = None 986 target = encode_literal_instantiator(objpath) 987 988 # Identified targets employ function pointers directly. 989 990 elif objpath: 991 parameters = self.importer.function_parameters.get(objpath) 992 993 # Class invocation involves instantiators. 994 995 if expr.has_kind("<class>"): 996 target = encode_instantiator_pointer(objpath) 997 target_structure = encode_initialiser_pointer(objpath) 998 999 # Only plain functions and bound methods employ function pointers. 1000 1001 elif expr.has_kind("<function>"): 1002 function = objpath 1003 1004 # Test for functions and methods. 1005 1006 accessor_kinds = expr.get_accessor_kinds() 1007 1008 if not self.is_method(objpath) or accessor_kinds and len(accessor_kinds) == 1 and first(accessor_kinds) == "<instance>": 1009 target = encode_function_pointer(objpath) 1010 target_structure = encode_path(objpath) 1011 1012 # Other targets are retrieved at run-time. 1013 1014 else: 1015 parameters = None 1016 1017 # Arguments are presented in a temporary frame array with any context 1018 # always being the first argument (although it may be set to null for 1019 # invocations where it would be unused). 1020 1021 args = ["__CONTEXT_AS_VALUE(__tmp_targets[%d])" % self.function_target] 1022 args += [None] * (not parameters and len(n.args) or parameters and len(parameters) or 0) 1023 kwcodes = [] 1024 kwargs = [] 1025 1026 # Any invocations in the arguments will store target details in a 1027 # different location. 1028 1029 self.function_target += 1 1030 1031 for i, arg in enumerate(n.args): 1032 argexpr = self.process_structure_node(arg) 1033 1034 # Store a keyword argument, either in the argument list or 1035 # in a separate keyword argument list for subsequent lookup. 1036 1037 if isinstance(arg, compiler.ast.Keyword): 1038 1039 # With knowledge of the target, store the keyword 1040 # argument directly. 1041 1042 if parameters: 1043 argnum = parameters.index(arg.name) 1044 args[argnum+1] = str(argexpr) 1045 1046 # Otherwise, store the details in a separate collection. 1047 1048 else: 1049 kwargs.append(str(argexpr)) 1050 kwcodes.append("{%s, %s}" % ( 1051 encode_symbol("ppos", arg.name), 1052 encode_symbol("pcode", arg.name))) 1053 1054 else: 1055 try: 1056 args[i+1] = str(argexpr) 1057 except IndexError: 1058 raise TranslateError("Too many arguments specified.", 1059 self.get_namespace_path(), n) 1060 1061 # Reference the current target again. 1062 1063 self.function_target -= 1 1064 1065 # Defaults are added to the frame where arguments are missing. 1066 1067 if parameters: 1068 function_defaults = self.importer.function_defaults.get(objpath) 1069 if function_defaults: 1070 1071 # Visit each default and set any missing arguments. 1072 # Use the target structure to obtain defaults, as opposed to the 1073 # actual function involved. 1074 1075 for i, (argname, default) in enumerate(function_defaults): 1076 argnum = parameters.index(argname) 1077 if not args[argnum+1]: 1078 args[argnum+1] = "__GETDEFAULT(&%s, %d)" % (target_structure, i) 1079 1080 # Test for missing arguments. 1081 1082 if None in args: 1083 raise TranslateError("Not all arguments supplied.", 1084 self.get_namespace_path(), n) 1085 1086 # Encode the arguments. 1087 1088 argstr = "__ARGS(%s)" % ", ".join(args) 1089 kwargstr = kwargs and ("__ARGS(%s)" % ", ".join(kwargs)) or "0" 1090 kwcodestr = kwcodes and ("__KWARGS(%s)" % ", ".join(kwcodes)) or "0" 1091 1092 # Where literal instantiation is occurring, add an argument indicating 1093 # the number of values. 1094 1095 if literal_instantiation: 1096 argstr += ", %d" % (len(args) - 1) 1097 1098 # First, the invocation expression is presented. 1099 1100 stages = [] 1101 1102 # Without a known specific callable, the expression provides the target. 1103 1104 stages.append("__tmp_targets[%d] = %s" % (self.function_target, expr)) 1105 1106 # Any specific callable is then obtained. 1107 1108 if target: 1109 stages.append(target) 1110 elif function: 1111 stages.append("__load_via_object(__tmp_targets[%d].value, %s).fn" % ( 1112 self.function_target, encode_symbol("pos", "__fn__"))) 1113 1114 # With a known target, the function is obtained directly and called. 1115 1116 if target or function: 1117 output = "(\n%s\n)(%s)" % (",\n".join(stages), argstr) 1118 1119 # With unknown targets, the generic invocation function is applied to 1120 # the callable and argument collections. 1121 1122 else: 1123 output = "(%s, __invoke(\n__tmp_targets[%d],\n%d, %d, %s, %s,\n%d, %s\n))" % ( 1124 ",\n".join(stages), 1125 self.function_target, 1126 self.always_callable and 1 or 0, 1127 len(kwargs), kwcodestr, kwargstr, 1128 len(args), argstr) 1129 1130 return make_expression(output) 1131 1132 def always_callable(self, refs): 1133 1134 "Determine whether all 'refs' are callable." 1135 1136 for ref in refs: 1137 if not ref.static(): 1138 return False 1139 else: 1140 origin = ref.final() 1141 if not self.importer.get_attribute(origin, "__fn__"): 1142 return False 1143 return True 1144 1145 def need_default_arguments(self, objpath, nargs): 1146 1147 """ 1148 Return whether any default arguments are needed when invoking the object 1149 given by 'objpath'. 1150 """ 1151 1152 parameters = self.importer.function_parameters.get(objpath) 1153 return nargs < len(parameters) 1154 1155 def process_lambda_node(self, n): 1156 1157 "Process the given lambda node 'n'." 1158 1159 name = self.get_lambda_name() 1160 function_name = self.get_object_path(name) 1161 1162 defaults = self.process_function_defaults(n, name, "__tmp_value") 1163 1164 # Without defaults, produce an attribute referring to the function. 1165 1166 if not defaults: 1167 return make_expression("((__attr) {0, &%s})" % encode_path(function_name)) 1168 1169 # With defaults, copy the function structure and set the defaults on the 1170 # copy. 1171 1172 else: 1173 return make_expression("(__tmp_value = __COPY(&%s, sizeof(%s)), %s, (__attr) {0, __tmp_value})" % ( 1174 encode_path(function_name), 1175 encode_symbol("obj", function_name), 1176 ", ".join(defaults))) 1177 1178 def process_logical_node(self, n): 1179 1180 """ 1181 Process the given operator node 'n'. 1182 1183 Convert ... to ... 1184 1185 <a> and <b> 1186 (__tmp_result = <a>, !__BOOL(__tmp_result)) ? __tmp_result : <b> 1187 1188 <a> or <b> 1189 (__tmp_result = <a>, __BOOL(__tmp_result)) ? __tmp_result : <b> 1190 """ 1191 1192 if isinstance(n, compiler.ast.And): 1193 op = "!" 1194 else: 1195 op = "" 1196 1197 results = [] 1198 1199 for node in n.nodes[:-1]: 1200 expr = self.process_structure_node(node) 1201 results.append("(__tmp_result = %s, %s__BOOL(__tmp_result)) ? __tmp_result : " % (expr, op)) 1202 1203 expr = self.process_structure_node(n.nodes[-1]) 1204 results.append(str(expr)) 1205 1206 return make_expression("(%s)" % "".join(results)) 1207 1208 def process_name_node(self, n, expr=None): 1209 1210 "Process the given name node 'n' with the optional assignment 'expr'." 1211 1212 # Determine whether the name refers to a static external entity. 1213 1214 if n.name in predefined_constants: 1215 return PredefinedConstantRef(n.name) 1216 1217 # Convert literal references, operator function names, and print 1218 # function names to references. 1219 1220 elif n.name.startswith("$L") or n.name.startswith("$op") or \ 1221 n.name.startswith("$print"): 1222 ref = self.importer.get_module(self.name).special.get(n.name) 1223 return TrResolvedNameRef(n.name, ref) 1224 1225 # Get the appropriate name for the name reference, using the same method 1226 # as in the inspector. 1227 1228 path = self.get_namespace_path() 1229 objpath = self.get_object_path(n.name) 1230 1231 # Determine any assigned globals. 1232 1233 globals = self.importer.get_module(self.name).scope_globals.get(path) 1234 if globals and n.name in globals: 1235 objpath = self.get_global_path(n.name) 1236 1237 # Get the static identity of the name. 1238 1239 ref = self.importer.identify(objpath) 1240 if ref and not ref.get_name(): 1241 ref = ref.alias(objpath) 1242 1243 # Obtain any resolved names for non-assignment names. 1244 1245 if not expr and not ref and self.in_function: 1246 locals = self.importer.function_locals.get(path) 1247 ref = locals and locals.get(n.name) 1248 1249 # Determine whether the name refers to a parameter. The generation of 1250 # parameter references is different from other names. 1251 1252 parameters = self.importer.function_parameters.get(path) 1253 parameter = n.name == "self" and self.in_method() or \ 1254 parameters and n.name in parameters 1255 1256 # Qualified names are used for resolved static references or for 1257 # static namespace members. The reference should be configured to return 1258 # such names. 1259 1260 return TrResolvedNameRef(n.name, ref, expr=expr, parameter=parameter) 1261 1262 def process_not_node(self, n): 1263 1264 "Process the given operator node 'n'." 1265 1266 return make_expression("(__BOOL(%s) ? %s : %s)" % 1267 (self.process_structure_node(n.expr), PredefinedConstantRef("False"), 1268 PredefinedConstantRef("True"))) 1269 1270 def process_raise_node(self, n): 1271 1272 "Process the given raise node 'n'." 1273 1274 # NOTE: Determine which raise statement variants should be permitted. 1275 1276 if n.expr1: 1277 self.writestmt("__Raise(%s);" % self.process_structure_node(n.expr1)) 1278 else: 1279 self.writestmt("__Complete;") 1280 1281 def process_return_node(self, n): 1282 1283 "Process the given return node 'n'." 1284 1285 expr = self.process_structure_node(n.value) or PredefinedConstantRef("None") 1286 if self.in_try_finally or self.in_try_except: 1287 self.writestmt("__Return(%s);" % expr) 1288 else: 1289 self.writestmt("return %s;" % expr) 1290 1291 return ReturnRef() 1292 1293 def process_try_node(self, n): 1294 1295 """ 1296 Process the given "try...except" node 'n'. 1297 """ 1298 1299 in_try_except = self.in_try_except 1300 self.in_try_except = True 1301 1302 # Use macros to implement exception handling. 1303 1304 self.writestmt("__Try") 1305 self.writeline("{") 1306 self.indent += 1 1307 self.process_structure_node(n.body) 1308 1309 # Put the else statement in another try block that handles any raised 1310 # exceptions and converts them to exceptions that will not be handled by 1311 # the main handling block. 1312 1313 if n.else_: 1314 self.writestmt("__Try") 1315 self.writeline("{") 1316 self.indent += 1 1317 self.process_structure_node(n.else_) 1318 self.indent -= 1 1319 self.writeline("}") 1320 self.writeline("__Catch (__tmp_exc)") 1321 self.writeline("{") 1322 self.indent += 1 1323 self.writeline("if (__tmp_exc.raising) __RaiseElse(__tmp_exc.arg);") 1324 self.writeline("else if (__tmp_exc.completing) __Throw(__tmp_exc);") 1325 self.indent -= 1 1326 self.writeline("}") 1327 1328 # Complete the try block and enter the finally block, if appropriate. 1329 1330 if self.in_try_finally: 1331 self.writestmt("__Complete;") 1332 1333 self.indent -= 1 1334 self.writeline("}") 1335 1336 self.in_try_except = in_try_except 1337 1338 # Handlers are tests within a common handler block. 1339 1340 self.writeline("__Catch (__tmp_exc)") 1341 self.writeline("{") 1342 self.indent += 1 1343 1344 # Introduce an if statement to handle the completion of a try block. 1345 1346 self.process_try_completion() 1347 1348 # Handle exceptions in else blocks converted to __RaiseElse, converting 1349 # them back to normal exceptions. 1350 1351 if n.else_: 1352 self.writeline("else if (__tmp_exc.raising_else) __Raise(__tmp_exc.arg);") 1353 1354 # Exception handling. 1355 1356 for name, var, handler in n.handlers: 1357 1358 # Test for specific exceptions. 1359 1360 if name is not None: 1361 name_ref = self.process_structure_node(name) 1362 self.writeline("else if (__BOOL(__fn_native__isinstance((__attr[]) {{0, 0}, __tmp_exc.arg, %s})))" % name_ref) 1363 else: 1364 self.writeline("else if (1)") 1365 1366 self.writeline("{") 1367 self.indent += 1 1368 1369 # Establish the local for the handler. 1370 1371 if var is not None: 1372 var_ref = self.process_name_node(var, make_expression("__tmp_exc")) 1373 1374 if handler is not None: 1375 self.process_structure_node(handler) 1376 1377 self.indent -= 1 1378 self.writeline("}") 1379 1380 # Re-raise unhandled exceptions. 1381 1382 self.writeline("else __Throw(__tmp_exc);") 1383 1384 # End the handler block. 1385 1386 self.indent -= 1 1387 self.writeline("}") 1388 1389 def process_try_finally_node(self, n): 1390 1391 """ 1392 Process the given "try...finally" node 'n'. 1393 """ 1394 1395 in_try_finally = self.in_try_finally 1396 self.in_try_finally = True 1397 1398 # Use macros to implement exception handling. 1399 1400 self.writestmt("__Try") 1401 self.writeline("{") 1402 self.indent += 1 1403 self.process_structure_node(n.body) 1404 self.indent -= 1 1405 self.writeline("}") 1406 1407 self.in_try_finally = in_try_finally 1408 1409 # Finally clauses handle special exceptions. 1410 1411 self.writeline("__Catch (__tmp_exc)") 1412 self.writeline("{") 1413 self.indent += 1 1414 self.process_structure_node(n.final) 1415 1416 # Introduce an if statement to handle the completion of a try block. 1417 1418 self.process_try_completion() 1419 self.writeline("else __Throw(__tmp_exc);") 1420 1421 self.indent -= 1 1422 self.writeline("}") 1423 1424 def process_try_completion(self): 1425 1426 "Generate a test for the completion of a try block." 1427 1428 self.writestmt("if (__tmp_exc.completing)") 1429 self.writeline("{") 1430 self.indent += 1 1431 1432 # Only use the normal return statement if no surrounding try blocks 1433 # apply. 1434 1435 if not self.in_try_finally and not self.in_try_except: 1436 self.writeline("if (!__ISNULL(__tmp_exc.arg)) return __tmp_exc.arg;") 1437 else: 1438 self.writeline("if (!__ISNULL(__tmp_exc.arg)) __Throw(__tmp_exc);") 1439 1440 self.indent -= 1 1441 self.writeline("}") 1442 1443 def process_while_node(self, n): 1444 1445 "Process the given while node 'n'." 1446 1447 self.writeline("while (1)") 1448 self.writeline("{") 1449 self.indent += 1 1450 test = self.process_structure_node(n.test) 1451 1452 # Emit the loop termination condition unless "while <true value>" is 1453 # indicated. 1454 1455 if not (isinstance(test, PredefinedConstantRef) and test.value): 1456 1457 # NOTE: This needs to evaluate whether the operand is true or false 1458 # NOTE: according to Python rules. 1459 1460 self.writeline("if (!__BOOL(%s))" % test) 1461 self.writeline("{") 1462 self.indent += 1 1463 if n.else_: 1464 self.process_structure_node(n.else_) 1465 self.writestmt("break;") 1466 self.indent -= 1 1467 self.writeline("}") 1468 1469 in_conditional = self.in_conditional 1470 self.in_conditional = True 1471 self.process_structure_node(n.body) 1472 self.in_conditional = in_conditional 1473 1474 self.indent -= 1 1475 self.writeline("}") 1476 1477 # Output generation. 1478 1479 def start_output(self): 1480 1481 "Write the declarations at the top of each source file." 1482 1483 print >>self.out, """\ 1484 #include "types.h" 1485 #include "exceptions.h" 1486 #include "ops.h" 1487 #include "progconsts.h" 1488 #include "progops.h" 1489 #include "progtypes.h" 1490 #include "main.h" 1491 """ 1492 1493 def start_module(self): 1494 1495 "Write the start of each module's main function." 1496 1497 print >>self.out, "void __main_%s()" % encode_path(self.name) 1498 print >>self.out, "{" 1499 self.indent += 1 1500 self.write_temporaries(self.importer.function_targets.get(self.name)) 1501 1502 def end_module(self): 1503 1504 "End each module by closing its main function." 1505 1506 self.indent -= 1 1507 print >>self.out, "}" 1508 1509 def start_function(self, name): 1510 1511 "Start the function having the given 'name'." 1512 1513 print >>self.out, "__attr %s(__attr __args[])" % encode_function_pointer(name) 1514 print >>self.out, "{" 1515 self.indent += 1 1516 self.write_temporaries(self.importer.function_targets.get(name)) 1517 1518 # Obtain local names from parameters. 1519 1520 parameters = self.importer.function_parameters[name] 1521 locals = self.importer.function_locals[name].keys() 1522 names = [] 1523 1524 for n in locals: 1525 1526 # Filter out special names and parameters. Note that self is a local 1527 # regardless of whether it originally appeared in the parameters or 1528 # not. 1529 1530 if n.startswith("$l") or n in parameters or n == "self": 1531 continue 1532 names.append(encode_path(n)) 1533 1534 # Emit required local names. 1535 1536 if names: 1537 names.sort() 1538 self.writeline("__attr %s;" % ", ".join(names)) 1539 1540 self.write_parameters(name) 1541 1542 def end_function(self, name): 1543 1544 "End the function having the given 'name'." 1545 1546 self.indent -= 1 1547 print >>self.out, "}" 1548 print >>self.out 1549 1550 def write_temporaries(self, targets): 1551 1552 """ 1553 Write temporary storage employed by functions, providing space for the 1554 given number of 'targets'. 1555 """ 1556 1557 targets = targets is not None and "__tmp_targets[%d], " % targets or "" 1558 1559 self.writeline("__ref __tmp_context, __tmp_value;") 1560 self.writeline("__attr %s__tmp_result;" % targets) 1561 self.writeline("__exc __tmp_exc;") 1562 1563 def write_parameters(self, name): 1564 1565 """ 1566 For the function having the given 'name', write definitions of 1567 parameters found in the arguments array. 1568 """ 1569 1570 parameters = self.importer.function_parameters[name] 1571 1572 # Generate any self reference. 1573 1574 if self.is_method(name): 1575 self.writeline("__attr * const self = &__args[0];") 1576 1577 # Generate aliases for the parameters. 1578 1579 for i, parameter in enumerate(parameters): 1580 self.writeline("__attr * const %s = &__args[%d];" % (encode_path(parameter), i+1)) 1581 1582 def start_if(self, first, test_ref): 1583 self.writestmt("%sif (__BOOL(%s))" % (not first and "else " or "", test_ref)) 1584 self.writeline("{") 1585 self.indent += 1 1586 1587 def end_if(self): 1588 self.indent -= 1 1589 self.writeline("}") 1590 1591 def start_else(self): 1592 self.writeline("else") 1593 self.writeline("{") 1594 self.indent += 1 1595 1596 def end_else(self): 1597 self.indent -= 1 1598 self.writeline("}") 1599 1600 def statement(self, expr): 1601 # NOTE: Should never be None. 1602 if not expr: 1603 self.writestmt("...;") 1604 s = str(expr) 1605 if s: 1606 self.writestmt("%s;" % s) 1607 1608 def statements(self, results): 1609 for result in results: 1610 self.statement(result) 1611 1612 def writeline(self, s): 1613 print >>self.out, "%s%s" % (self.pad(), self.indenttext(s, self.indent + 1)) 1614 1615 def writestmt(self, s): 1616 print >>self.out 1617 self.writeline(s) 1618 1619 def write_comment(self, s): 1620 self.writestmt("/* %s */" % s) 1621 1622 def pad(self, extra=0): 1623 return (self.indent + extra) * self.tabstop 1624 1625 def indenttext(self, s, levels): 1626 lines = s.split("\n") 1627 out = [lines[0]] 1628 for line in lines[1:]: 1629 out.append(levels * self.tabstop + line) 1630 if line.endswith("("): 1631 levels += 1 1632 elif line.startswith(")"): 1633 levels -= 1 1634 return "\n".join(out) 1635 1636 # vim: tabstop=4 expandtab shiftwidth=4