#!/usr/bin/python """A glorified C pre-processor parser.""" import ctypes import logging import os import re import site import utils top = os.getenv('ANDROID_BUILD_TOP') if top is None: utils.panic('ANDROID_BUILD_TOP not set.\n') # Set up the env vars for libclang. site.addsitedir(os.path.join(top, 'external/clang/bindings/python')) import clang.cindex from clang.cindex import conf from clang.cindex import Cursor from clang.cindex import CursorKind from clang.cindex import SourceLocation from clang.cindex import SourceRange from clang.cindex import TokenGroup from clang.cindex import TokenKind from clang.cindex import TranslationUnit # Set up LD_LIBRARY_PATH to include libclang.so, libLLVM.so, and etc. # Note that setting LD_LIBRARY_PATH with os.putenv() sometimes doesn't help. clang.cindex.Config.set_library_path(os.path.join(top, 'prebuilts/sdk/tools/linux/lib64')) from defaults import kCppUndefinedMacro from defaults import kernel_remove_config_macros from defaults import kernel_token_replacements debugBlockParser = False debugCppExpr = False debugOptimIf01 = False ############################################################################### ############################################################################### ##### ##### ##### C P P T O K E N S ##### ##### ##### ############################################################################### ############################################################################### # the list of supported C-preprocessor tokens # plus a couple of C tokens as well tokEOF = "\0" tokLN = "\n" tokSTRINGIFY = "#" tokCONCAT = "##" tokLOGICAND = "&&" tokLOGICOR = "||" tokSHL = "<<" tokSHR = ">>" tokEQUAL = "==" tokNEQUAL = "!=" tokLT = "<" tokLTE = "<=" tokGT = ">" tokGTE = ">=" tokELLIPSIS = "..." tokSPACE = " " tokDEFINED = "defined" tokLPAREN = "(" tokRPAREN = ")" tokNOT = "!" tokPLUS = "+" tokMINUS = "-" tokMULTIPLY = "*" tokDIVIDE = "/" tokMODULUS = "%" tokBINAND = "&" tokBINOR = "|" tokBINXOR = "^" tokCOMMA = "," tokLBRACE = "{" tokRBRACE = "}" tokARROW = "->" tokINCREMENT = "++" tokDECREMENT = "--" tokNUMBER = "<number>" tokIDENT = "<ident>" tokSTRING = "<string>" class Token(clang.cindex.Token): """A class that represents one token after parsing. It inherits the class in libclang, with an extra id property to hold the new spelling of the token. The spelling property in the base class is defined as read-only. New names after macro instantiation are saved in their ids now. It also facilitates the renaming of directive optimizations like replacing 'ifndef X' with 'if !defined(X)'. It also overrides the cursor property of the base class. Because the one in libclang always queries based on a single token, which usually doesn't hold useful information. The cursor in this class can be set by calling CppTokenizer.getTokensWithCursors(). Otherwise it returns the one in the base class. """ def __init__(self, tu=None, group=None, int_data=None, ptr_data=None, cursor=None): clang.cindex.Token.__init__(self) self._id = None self._tu = tu self._group = group self._cursor = cursor # self.int_data and self.ptr_data are from the base class. But # self.int_data doesn't accept a None value. if int_data is not None: self.int_data = int_data self.ptr_data = ptr_data @property def id(self): """Name of the token.""" if self._id is None: return self.spelling else: return self._id @id.setter def id(self, new_id): """Setting name of the token.""" self._id = new_id @property def cursor(self): if self._cursor is None: self._cursor = clang.cindex.Token.cursor return self._cursor @cursor.setter def cursor(self, new_cursor): self._cursor = new_cursor def __repr__(self): if self.id == 'defined': return self.id elif self.kind == TokenKind.IDENTIFIER: return "(ident %s)" % self.id return self.id def __str__(self): return self.id class BadExpectedToken(Exception): """An exception that will be raised for unexpected tokens.""" pass # The __contains__ function in libclang SourceRange class contains a bug. It # gives wrong result when dealing with single line range. # Bug filed with upstream: # http://llvm.org/bugs/show_bug.cgi?id=22243, http://reviews.llvm.org/D7277 def SourceRange__contains__(self, other): """Determine if a given location is inside the range.""" if not isinstance(other, SourceLocation): return False if other.file is None and self.start.file is None: pass elif (self.start.file.name != other.file.name or other.file.name != self.end.file.name): # same file name return False # same file, in between lines if self.start.line < other.line < self.end.line: return True # same file, same line elif self.start.line == other.line == self.end.line: if self.start.column <= other.column <= self.end.column: return True elif self.start.line == other.line: # same file first line if self.start.column <= other.column: return True elif other.line == self.end.line: # same file last line if other.column <= self.end.column: return True return False SourceRange.__contains__ = SourceRange__contains__ ################################################################################ ################################################################################ ##### ##### ##### C P P T O K E N I Z E R ##### ##### ##### ################################################################################ ################################################################################ class CppTokenizer(object): """A tokenizer that converts some input text into a list of tokens. It calls libclang's tokenizer to get the parsed tokens. In addition, it updates the cursor property in each token after parsing, by calling getTokensWithCursors(). """ clang_flags = ['-E', '-x', 'c'] options = TranslationUnit.PARSE_DETAILED_PROCESSING_RECORD def __init__(self): """Initialize a new CppTokenizer object.""" self._indexer = clang.cindex.Index.create() self._tu = None self._index = 0 self.tokens = None def _getTokensWithCursors(self): """Helper method to return all tokens with their cursors. The cursor property in a clang Token doesn't provide enough information. Because it is queried based on single token each time without any context, i.e. via calling conf.lib.clang_annotateTokens() with only one token given. So we often see 'INVALID_FILE' in one token's cursor. In this function it passes all the available tokens to get more informative cursors. """ tokens_memory = ctypes.POINTER(clang.cindex.Token)() tokens_count = ctypes.c_uint() conf.lib.clang_tokenize(self._tu, self._tu.cursor.extent, ctypes.byref(tokens_memory), ctypes.byref(tokens_count)) count = int(tokens_count.value) # If we get no tokens, no memory was allocated. Be sure not to return # anything and potentially call a destructor on nothing. if count < 1: return cursors = (Cursor * count)() cursors_memory = ctypes.cast(cursors, ctypes.POINTER(Cursor)) conf.lib.clang_annotateTokens(self._tu, tokens_memory, count, cursors_memory) tokens_array = ctypes.cast( tokens_memory, ctypes.POINTER(clang.cindex.Token * count)).contents token_group = TokenGroup(self._tu, tokens_memory, tokens_count) tokens = [] for i in xrange(0, count): token = Token(self._tu, token_group, int_data=tokens_array[i].int_data, ptr_data=tokens_array[i].ptr_data, cursor=cursors[i]) # We only want non-comment tokens. if token.kind != TokenKind.COMMENT: tokens.append(token) return tokens def parseString(self, lines): """Parse a list of text lines into a BlockList object.""" file_ = 'dummy.c' self._tu = self._indexer.parse(file_, self.clang_flags, unsaved_files=[(file_, lines)], options=self.options) self.tokens = self._getTokensWithCursors() def parseFile(self, file_): """Parse a file into a BlockList object.""" self._tu = self._indexer.parse(file_, self.clang_flags, options=self.options) self.tokens = self._getTokensWithCursors() def nextToken(self): """Return next token from the list.""" if self._index < len(self.tokens): t = self.tokens[self._index] self._index += 1 return t else: return None class CppStringTokenizer(CppTokenizer): """A CppTokenizer derived class that accepts a string of text as input.""" def __init__(self, line): CppTokenizer.__init__(self) self.parseString(line) class CppFileTokenizer(CppTokenizer): """A CppTokenizer derived class that accepts a file as input.""" def __init__(self, file_): CppTokenizer.__init__(self) self.parseFile(file_) # Unit testing # class CppTokenizerTester(object): """A class used to test CppTokenizer classes.""" def __init__(self, tokenizer=None): self._tokenizer = tokenizer self._token = None def setTokenizer(self, tokenizer): self._tokenizer = tokenizer def expect(self, id): self._token = self._tokenizer.nextToken() if self._token is None: tokid = '' else: tokid = self._token.id if tokid == id: return raise BadExpectedToken("### BAD TOKEN: '%s' expecting '%s'" % ( tokid, id)) def expectToken(self, id, line, col): self.expect(id) if self._token.location.line != line: raise BadExpectedToken( "### BAD LINENO: token '%s' got '%d' expecting '%d'" % ( id, self._token.lineno, line)) if self._token.location.column != col: raise BadExpectedToken("### BAD COLNO: '%d' expecting '%d'" % ( self._token.colno, col)) def expectTokens(self, tokens): for id, line, col in tokens: self.expectToken(id, line, col) def expectList(self, list_): for item in list_: self.expect(item) def test_CppTokenizer(): tester = CppTokenizerTester() tester.setTokenizer(CppStringTokenizer("#an/example && (01923_xy)")) tester.expectList(["#", "an", "/", "example", tokLOGICAND, tokLPAREN, "01923_xy", tokRPAREN]) tester.setTokenizer(CppStringTokenizer("FOO(BAR) && defined(BAZ)")) tester.expectList(["FOO", tokLPAREN, "BAR", tokRPAREN, tokLOGICAND, "defined", tokLPAREN, "BAZ", tokRPAREN]) tester.setTokenizer(CppStringTokenizer("/*\n#\n*/")) tester.expectList([]) tester.setTokenizer(CppStringTokenizer("first\nsecond")) tester.expectList(["first", "second"]) tester.setTokenizer(CppStringTokenizer("first second\n third")) tester.expectTokens([("first", 1, 1), ("second", 1, 7), ("third", 2, 3)]) tester.setTokenizer(CppStringTokenizer("boo /* what the\nhell */")) tester.expectTokens([("boo", 1, 1)]) tester.setTokenizer(CppStringTokenizer("an \\\n example")) tester.expectTokens([("an", 1, 1), ("example", 2, 2)]) return True ################################################################################ ################################################################################ ##### ##### ##### C P P E X P R E S S I O N S ##### ##### ##### ################################################################################ ################################################################################ class CppExpr(object): """A class that models the condition of #if directives into an expr tree. Each node in the tree is of the form (op, arg) or (op, arg1, arg2) where "op" is a string describing the operation """ unaries = ["!", "~"] binaries = ["+", "-", "<", "<=", ">=", ">", "&&", "||", "*", "/", "%", "&", "|", "^", "<<", ">>", "==", "!=", "?", ":"] precedences = { "?": 1, ":": 1, "||": 2, "&&": 3, "|": 4, "^": 5, "&": 6, "==": 7, "!=": 7, "<": 8, "<=": 8, ">": 8, ">=": 8, "<<": 9, ">>": 9, "+": 10, "-": 10, "*": 11, "/": 11, "%": 11, "!": 12, "~": 12 } def __init__(self, tokens): """Initialize a CppExpr. 'tokens' must be a CppToken list.""" self.tokens = tokens self._num_tokens = len(tokens) self._index = 0 if debugCppExpr: print "CppExpr: trying to parse %s" % repr(tokens) self.expr = self.parseExpression(0) if debugCppExpr: print "CppExpr: got " + repr(self.expr) if self._index != self._num_tokens: self.throw(BadExpectedToken, "crap at end of input (%d != %d): %s" % (self._index, self._num_tokens, repr(tokens))) def throw(self, exception, msg): if self._index < self._num_tokens: tok = self.tokens[self._index] print "%d:%d: %s" % (tok.location.line, tok.location.column, msg) else: print "EOF: %s" % msg raise exception(msg) def expectId(self, id): """Check that a given token id is at the current position.""" token = self.tokens[self._index] if self._index >= self._num_tokens or token.id != id: self.throw(BadExpectedToken, "### expecting '%s' in expression, got '%s'" % ( id, token.id)) self._index += 1 def is_decimal(self): token = self.tokens[self._index].id if token[-1] in "ULul": token = token[:-1] try: val = int(token, 10) self._index += 1 return ('int', val) except ValueError: return None def is_octal(self): token = self.tokens[self._index].id if token[-1] in "ULul": token = token[:-1] if len(token) < 2 or token[0] != '0': return None try: val = int(token, 8) self._index += 1 return ('oct', val) except ValueError: return None def is_hexadecimal(self): token = self.tokens[self._index].id if token[-1] in "ULul": token = token[:-1] if len(token) < 3 or (token[:2] != '0x' and token[:2] != '0X'): return None try: val = int(token, 16) self._index += 1 return ('hex', val) except ValueError: return None def is_integer(self): if self.tokens[self._index].kind != TokenKind.LITERAL: return None c = self.is_hexadecimal() if c: return c c = self.is_octal() if c: return c c = self.is_decimal() if c: return c return None def is_number(self): t = self.tokens[self._index] if t.id == tokMINUS and self._index + 1 < self._num_tokens: self._index += 1 c = self.is_integer() if c: op, val = c return (op, -val) if t.id == tokPLUS and self._index + 1 < self._num_tokens: self._index += 1 c = self.is_integer() if c: return c return self.is_integer() def is_defined(self): t = self.tokens[self._index] if t.id != tokDEFINED: return None # We have the defined keyword, check the rest. self._index += 1 used_parens = False if (self._index < self._num_tokens and self.tokens[self._index].id == tokLPAREN): used_parens = True self._index += 1 if self._index >= self._num_tokens: self.throw(BadExpectedToken, "### 'defined' must be followed by macro name or left " "paren") t = self.tokens[self._index] if t.kind != TokenKind.IDENTIFIER: self.throw(BadExpectedToken, "### 'defined' must be followed by macro name") self._index += 1 if used_parens: self.expectId(tokRPAREN) return ("defined", t.id) def is_call_or_ident(self): if self._index >= self._num_tokens: return None t = self.tokens[self._index] if t.kind != TokenKind.IDENTIFIER: return None name = t.id self._index += 1 if (self._index >= self._num_tokens or self.tokens[self._index].id != tokLPAREN): return ("ident", name) params = [] depth = 1 self._index += 1 j = self._index while self._index < self._num_tokens: id = self.tokens[self._index].id if id == tokLPAREN: depth += 1 elif depth == 1 and (id == tokCOMMA or id == tokRPAREN): k = self._index param = self.tokens[j:k] params.append(param) if id == tokRPAREN: break j = self._index + 1 elif id == tokRPAREN: depth -= 1 self._index += 1 if self._index >= self._num_tokens: return None self._index += 1 return ("call", (name, params)) # Implements the "precedence climbing" algorithm from # http://www.engr.mun.ca/~theo/Misc/exp_parsing.htm. # The "classic" algorithm would be fine if we were using a tool to # generate the parser, but we're not. Dijkstra's "shunting yard" # algorithm hasn't been necessary yet. def parseExpression(self, minPrecedence): if self._index >= self._num_tokens: return None node = self.parsePrimary() while (self.token() and self.isBinary(self.token()) and self.precedence(self.token()) >= minPrecedence): op = self.token() self.nextToken() rhs = self.parseExpression(self.precedence(op) + 1) node = (op.id, node, rhs) return node def parsePrimary(self): op = self.token() if self.isUnary(op): self.nextToken() return (op.id, self.parseExpression(self.precedence(op))) primary = None if op.id == tokLPAREN: self.nextToken() primary = self.parseExpression(0) self.expectId(tokRPAREN) elif op.id == "?": self.nextToken() primary = self.parseExpression(0) self.expectId(":") elif op.id == '+' or op.id == '-' or op.kind == TokenKind.LITERAL: primary = self.is_number() # Checking for 'defined' needs to come first now because 'defined' is # recognized as IDENTIFIER. elif op.id == tokDEFINED: primary = self.is_defined() elif op.kind == TokenKind.IDENTIFIER: primary = self.is_call_or_ident() else: self.throw(BadExpectedToken, "didn't expect to see a %s in factor" % ( self.tokens[self._index].id)) return primary def isBinary(self, token): return token.id in self.binaries def isUnary(self, token): return token.id in self.unaries def precedence(self, token): return self.precedences.get(token.id) def token(self): if self._index >= self._num_tokens: return None return self.tokens[self._index] def nextToken(self): self._index += 1 if self._index >= self._num_tokens: return None return self.tokens[self._index] def dump_node(self, e): op = e[0] line = "(" + op if op == "int": line += " %d)" % e[1] elif op == "oct": line += " 0%o)" % e[1] elif op == "hex": line += " 0x%x)" % e[1] elif op == "ident": line += " %s)" % e[1] elif op == "defined": line += " %s)" % e[1] elif op == "call": arg = e[1] line += " %s [" % arg[0] prefix = "" for param in arg[1]: par = "" for tok in param: par += str(tok) line += "%s%s" % (prefix, par) prefix = "," line += "])" elif op in CppExpr.unaries: line += " %s)" % self.dump_node(e[1]) elif op in CppExpr.binaries: line += " %s %s)" % (self.dump_node(e[1]), self.dump_node(e[2])) else: line += " ?%s)" % repr(e[1]) return line def __repr__(self): return self.dump_node(self.expr) def source_node(self, e): op = e[0] if op == "int": return "%d" % e[1] if op == "hex": return "0x%x" % e[1] if op == "oct": return "0%o" % e[1] if op == "ident": # XXX: should try to expand return e[1] if op == "defined": return "defined(%s)" % e[1] prec = CppExpr.precedences.get(op, 1000) arg = e[1] if op in CppExpr.unaries: arg_src = self.source_node(arg) arg_op = arg[0] arg_prec = CppExpr.precedences.get(arg_op, 1000) if arg_prec < prec: return "!(" + arg_src + ")" else: return "!" + arg_src if op in CppExpr.binaries: arg2 = e[2] arg1_op = arg[0] arg2_op = arg2[0] arg1_src = self.source_node(arg) arg2_src = self.source_node(arg2) if CppExpr.precedences.get(arg1_op, 1000) < prec: arg1_src = "(%s)" % arg1_src if CppExpr.precedences.get(arg2_op, 1000) < prec: arg2_src = "(%s)" % arg2_src return "%s %s %s" % (arg1_src, op, arg2_src) return "???" def __str__(self): return self.source_node(self.expr) @staticmethod def int_node(e): if e[0] in ["int", "oct", "hex"]: return e[1] else: return None def toInt(self): return self.int_node(self.expr) def optimize_node(self, e, macros=None): if macros is None: macros = {} op = e[0] if op == "defined": op, name = e if macros.has_key(name): if macros[name] == kCppUndefinedMacro: return ("int", 0) else: try: value = int(macros[name]) return ("int", value) except ValueError: return ("defined", macros[name]) if kernel_remove_config_macros and name.startswith("CONFIG_"): return ("int", 0) return e elif op == "ident": op, name = e if macros.has_key(name): try: value = int(macros[name]) expanded = ("int", value) except ValueError: expanded = ("ident", macros[name]) return self.optimize_node(expanded, macros) return e elif op == "!": op, v = e v = self.optimize_node(v, macros) if v[0] == "int": if v[1] == 0: return ("int", 1) else: return ("int", 0) return ('!', v) elif op == "&&": op, l, r = e l = self.optimize_node(l, macros) r = self.optimize_node(r, macros) li = self.int_node(l) ri = self.int_node(r) if li is not None: if li == 0: return ("int", 0) else: return r elif ri is not None: if ri == 0: return ("int", 0) else: return l return (op, l, r) elif op == "||": op, l, r = e l = self.optimize_node(l, macros) r = self.optimize_node(r, macros) li = self.int_node(l) ri = self.int_node(r) if li is not None: if li == 0: return r else: return ("int", 1) elif ri is not None: if ri == 0: return l else: return ("int", 1) return (op, l, r) else: return e def optimize(self, macros=None): if macros is None: macros = {} self.expr = self.optimize_node(self.expr, macros) def test_cpp_expr(expr, expected): e = CppExpr(CppStringTokenizer(expr).tokens) s1 = repr(e) if s1 != expected: print ("[FAIL]: expression '%s' generates '%s', should be " "'%s'" % (expr, s1, expected)) global failure_count failure_count += 1 def test_cpp_expr_optim(expr, expected, macros=None): if macros is None: macros = {} e = CppExpr(CppStringTokenizer(expr).tokens) e.optimize(macros) s1 = repr(e) if s1 != expected: print ("[FAIL]: optimized expression '%s' generates '%s' with " "macros %s, should be '%s'" % (expr, s1, macros, expected)) global failure_count failure_count += 1 def test_cpp_expr_source(expr, expected): e = CppExpr(CppStringTokenizer(expr).tokens) s1 = str(e) if s1 != expected: print ("[FAIL]: source expression '%s' generates '%s', should " "be '%s'" % (expr, s1, expected)) global failure_count failure_count += 1 def test_CppExpr(): test_cpp_expr("0", "(int 0)") test_cpp_expr("1", "(int 1)") test_cpp_expr("-5", "(int -5)") test_cpp_expr("+1", "(int 1)") test_cpp_expr("0U", "(int 0)") test_cpp_expr("015", "(oct 015)") test_cpp_expr("015l", "(oct 015)") test_cpp_expr("0x3e", "(hex 0x3e)") test_cpp_expr("(0)", "(int 0)") test_cpp_expr("1 && 1", "(&& (int 1) (int 1))") test_cpp_expr("1 && 0", "(&& (int 1) (int 0))") test_cpp_expr("EXAMPLE", "(ident EXAMPLE)") test_cpp_expr("EXAMPLE - 3", "(- (ident EXAMPLE) (int 3))") test_cpp_expr("defined(EXAMPLE)", "(defined EXAMPLE)") test_cpp_expr("defined ( EXAMPLE ) ", "(defined EXAMPLE)") test_cpp_expr("!defined(EXAMPLE)", "(! (defined EXAMPLE))") test_cpp_expr("defined(ABC) || defined(BINGO)", "(|| (defined ABC) (defined BINGO))") test_cpp_expr("FOO(BAR,5)", "(call FOO [BAR,5])") test_cpp_expr("A == 1 || defined(B)", "(|| (== (ident A) (int 1)) (defined B))") test_cpp_expr_optim("0", "(int 0)") test_cpp_expr_optim("1", "(int 1)") test_cpp_expr_optim("1 && 1", "(int 1)") test_cpp_expr_optim("1 && +1", "(int 1)") test_cpp_expr_optim("0x1 && 01", "(oct 01)") test_cpp_expr_optim("1 && 0", "(int 0)") test_cpp_expr_optim("0 && 1", "(int 0)") test_cpp_expr_optim("0 && 0", "(int 0)") test_cpp_expr_optim("1 || 1", "(int 1)") test_cpp_expr_optim("1 || 0", "(int 1)") test_cpp_expr_optim("0 || 1", "(int 1)") test_cpp_expr_optim("0 || 0", "(int 0)") test_cpp_expr_optim("A", "(ident A)") test_cpp_expr_optim("A", "(int 1)", {"A": 1}) test_cpp_expr_optim("A || B", "(int 1)", {"A": 1}) test_cpp_expr_optim("A || B", "(int 1)", {"B": 1}) test_cpp_expr_optim("A && B", "(ident B)", {"A": 1}) test_cpp_expr_optim("A && B", "(ident A)", {"B": 1}) test_cpp_expr_optim("A && B", "(&& (ident A) (ident B))") test_cpp_expr_optim("EXAMPLE", "(ident EXAMPLE)") test_cpp_expr_optim("EXAMPLE - 3", "(- (ident EXAMPLE) (int 3))") test_cpp_expr_optim("defined(EXAMPLE)", "(defined EXAMPLE)") test_cpp_expr_optim("defined(EXAMPLE)", "(defined XOWOE)", {"EXAMPLE": "XOWOE"}) test_cpp_expr_optim("defined(EXAMPLE)", "(int 0)", {"EXAMPLE": kCppUndefinedMacro}) test_cpp_expr_optim("!defined(EXAMPLE)", "(! (defined EXAMPLE))") test_cpp_expr_optim("!defined(EXAMPLE)", "(! (defined XOWOE))", {"EXAMPLE": "XOWOE"}) test_cpp_expr_optim("!defined(EXAMPLE)", "(int 1)", {"EXAMPLE": kCppUndefinedMacro}) test_cpp_expr_optim("defined(A) || defined(B)", "(|| (defined A) (defined B))") test_cpp_expr_optim("defined(A) || defined(B)", "(int 1)", {"A": "1"}) test_cpp_expr_optim("defined(A) || defined(B)", "(int 1)", {"B": "1"}) test_cpp_expr_optim("defined(A) || defined(B)", "(defined A)", {"B": kCppUndefinedMacro}) test_cpp_expr_optim("defined(A) || defined(B)", "(int 0)", {"A": kCppUndefinedMacro, "B": kCppUndefinedMacro}) test_cpp_expr_optim("defined(A) && defined(B)", "(&& (defined A) (defined B))") test_cpp_expr_optim("defined(A) && defined(B)", "(defined B)", {"A": "1"}) test_cpp_expr_optim("defined(A) && defined(B)", "(defined A)", {"B": "1"}) test_cpp_expr_optim("defined(A) && defined(B)", "(int 0)", {"B": kCppUndefinedMacro}) test_cpp_expr_optim("defined(A) && defined(B)", "(int 0)", {"A": kCppUndefinedMacro}) test_cpp_expr_optim("A == 1 || defined(B)", "(|| (== (ident A) (int 1)) (defined B))") test_cpp_expr_optim( "defined(__KERNEL__) || !defined(__GLIBC__) || (__GLIBC__ < 2)", "(|| (! (defined __GLIBC__)) (< (ident __GLIBC__) (int 2)))", {"__KERNEL__": kCppUndefinedMacro}) test_cpp_expr_source("0", "0") test_cpp_expr_source("1", "1") test_cpp_expr_source("1 && 1", "1 && 1") test_cpp_expr_source("1 && 0", "1 && 0") test_cpp_expr_source("0 && 1", "0 && 1") test_cpp_expr_source("0 && 0", "0 && 0") test_cpp_expr_source("1 || 1", "1 || 1") test_cpp_expr_source("1 || 0", "1 || 0") test_cpp_expr_source("0 || 1", "0 || 1") test_cpp_expr_source("0 || 0", "0 || 0") test_cpp_expr_source("EXAMPLE", "EXAMPLE") test_cpp_expr_source("EXAMPLE - 3", "EXAMPLE - 3") test_cpp_expr_source("defined(EXAMPLE)", "defined(EXAMPLE)") test_cpp_expr_source("defined EXAMPLE", "defined(EXAMPLE)") test_cpp_expr_source("A == 1 || defined(B)", "A == 1 || defined(B)") ################################################################################ ################################################################################ ##### ##### ##### C P P B L O C K ##### ##### ##### ################################################################################ ################################################################################ class Block(object): """A class used to model a block of input source text. There are two block types: - directive blocks: contain the tokens of a single pre-processor directive (e.g. #if) - text blocks, contain the tokens of non-directive blocks The cpp parser class below will transform an input source file into a list of Block objects (grouped in a BlockList object for convenience) """ def __init__(self, tokens, directive=None, lineno=0, identifier=None): """Initialize a new block, if 'directive' is None, it is a text block. NOTE: This automatically converts '#ifdef MACRO' into '#if defined(MACRO)' and '#ifndef MACRO' into '#if !defined(MACRO)'. """ if directive == "ifdef": tok = Token() tok.id = tokDEFINED tokens = [tok] + tokens directive = "if" elif directive == "ifndef": tok1 = Token() tok2 = Token() tok1.id = tokNOT tok2.id = tokDEFINED tokens = [tok1, tok2] + tokens directive = "if" self.tokens = tokens self.directive = directive self.define_id = identifier if lineno > 0: self.lineno = lineno else: self.lineno = self.tokens[0].location.line if self.isIf(): self.expr = CppExpr(self.tokens) def isDirective(self): """Return True iff this is a directive block.""" return self.directive is not None def isConditional(self): """Return True iff this is a conditional directive block.""" return self.directive in ["if", "ifdef", "ifndef", "else", "elif", "endif"] def isDefine(self): """Return the macro name in a #define directive, or None otherwise.""" if self.directive != "define": return None return self.define_id def isIf(self): """Return True iff this is an #if-like directive block.""" return self.directive in ["if", "ifdef", "ifndef", "elif"] def isEndif(self): """Return True iff this is an #endif directive block.""" return self.directive == "endif" def isInclude(self): """Check whether this is a #include directive. If true, returns the corresponding file name (with brackets or double-qoutes). None otherwise. """ if self.directive != "include": return None return ''.join([str(x) for x in self.tokens]) @staticmethod def format_blocks(tokens, indent=0): """Return the formatted lines of strings with proper indentation.""" newline = True result = [] buf = '' i = 0 while i < len(tokens): t = tokens[i] if t.id == '{': buf += ' {' result.append(strip_space(buf)) indent += 2 buf = '' newline = True elif t.id == '}': indent -= 2 if not newline: result.append(strip_space(buf)) # Look ahead to determine if it's the end of line. if (i + 1 < len(tokens) and (tokens[i+1].id == ';' or tokens[i+1].id in ['else', '__attribute__', '__attribute', '__packed'] or tokens[i+1].kind == TokenKind.IDENTIFIER)): buf = ' ' * indent + '}' newline = False else: result.append(' ' * indent + '}') buf = '' newline = True elif t.id == ';': result.append(strip_space(buf) + ';') buf = '' newline = True # We prefer a new line for each constant in enum. elif t.id == ',' and t.cursor.kind == CursorKind.ENUM_DECL: result.append(strip_space(buf) + ',') buf = '' newline = True else: if newline: buf += ' ' * indent + str(t) else: buf += ' ' + str(t) newline = False i += 1 if buf: result.append(strip_space(buf)) return result, indent def writeWithWarning(self, out, warning, left_count, repeat_count, indent): """Dump the current block with warnings.""" # removeWhiteSpace() will sometimes creates non-directive blocks # without any tokens. These come from blocks that only contained # empty lines and spaces. They should not be printed in the final # output, and then should not be counted for this operation. # if self.directive is None and not self.tokens: return left_count, indent if self.directive: out.write(str(self) + '\n') left_count -= 1 if left_count == 0: out.write(warning) left_count = repeat_count else: lines, indent = self.format_blocks(self.tokens, indent) for line in lines: out.write(line + '\n') left_count -= 1 if left_count == 0: out.write(warning) left_count = repeat_count return left_count, indent def __repr__(self): """Generate the representation of a given block.""" if self.directive: result = "#%s " % self.directive if self.isIf(): result += repr(self.expr) else: for tok in self.tokens: result += repr(tok) else: result = "" for tok in self.tokens: result += repr(tok) return result def __str__(self): """Generate the string representation of a given block.""" if self.directive: # "#if" if self.directive == "if": # small optimization to re-generate #ifdef and #ifndef e = self.expr.expr op = e[0] if op == "defined": result = "#ifdef %s" % e[1] elif op == "!" and e[1][0] == "defined": result = "#ifndef %s" % e[1][1] else: result = "#if " + str(self.expr) # "#define" elif self.isDefine(): result = "#%s %s" % (self.directive, self.define_id) if self.tokens: result += " " expr = strip_space(' '.join([tok.id for tok in self.tokens])) # remove the space between name and '(' in function call result += re.sub(r'(\w+) \(', r'\1(', expr) # "#error" # Concatenating tokens with a space separator, because they may # not be quoted and broken into several tokens elif self.directive == "error": result = "#error %s" % ' '.join([tok.id for tok in self.tokens]) else: result = "#%s" % self.directive if self.tokens: result += " " result += ''.join([tok.id for tok in self.tokens]) else: lines, _ = self.format_blocks(self.tokens) result = '\n'.join(lines) return result class BlockList(object): """A convenience class used to hold and process a list of blocks. It calls the cpp parser to get the blocks. """ def __init__(self, blocks): self.blocks = blocks def __len__(self): return len(self.blocks) def __getitem__(self, n): return self.blocks[n] def __repr__(self): return repr(self.blocks) def __str__(self): result = '\n'.join([str(b) for b in self.blocks]) return result def dump(self): """Dump all the blocks in current BlockList.""" print '##### BEGIN #####' for i, b in enumerate(self.blocks): print '### BLOCK %d ###' % i print b print '##### END #####' def optimizeIf01(self): """Remove the code between #if 0 .. #endif in a BlockList.""" self.blocks = optimize_if01(self.blocks) def optimizeMacros(self, macros): """Remove known defined and undefined macros from a BlockList.""" for b in self.blocks: if b.isIf(): b.expr.optimize(macros) def removeMacroDefines(self, macros): """Remove known macro definitions from a BlockList.""" self.blocks = remove_macro_defines(self.blocks, macros) def optimizeAll(self, macros): self.optimizeMacros(macros) self.optimizeIf01() return def findIncludes(self): """Return the list of included files in a BlockList.""" result = [] for b in self.blocks: i = b.isInclude() if i: result.append(i) return result def write(self, out): out.write(str(self)) def writeWithWarning(self, out, warning, repeat_count): left_count = repeat_count indent = 0 for b in self.blocks: left_count, indent = b.writeWithWarning(out, warning, left_count, repeat_count, indent) def removeVarsAndFuncs(self, knownStatics=None): """Remove variable and function declarations. All extern and static declarations corresponding to variable and function declarations are removed. We only accept typedefs and enum/structs/union declarations. However, we keep the definitions corresponding to the set of known static inline functions in the set 'knownStatics', which is useful for optimized byteorder swap functions and stuff like that. """ # NOTE: It's also removing function-like macros, such as __SYSCALL(...) # in uapi/asm-generic/unistd.h, or KEY_FIELD(...) in linux/bcache.h. # It could be problematic when we have function-like macros but without # '}' following them. It will skip all the tokens/blocks until seeing a # '}' as the function end. Fortunately we don't have such cases in the # current kernel headers. # state = 0 => normal (i.e. LN + spaces) # state = 1 => typedef/struct encountered, ends with ";" # state = 2 => var declaration encountered, ends with ";" # state = 3 => func declaration encountered, ends with "}" if knownStatics is None: knownStatics = set() state = 0 depth = 0 blocks2 = [] skipTokens = False for b in self.blocks: if b.isDirective(): blocks2.append(b) else: n = len(b.tokens) i = 0 if skipTokens: first = n else: first = 0 while i < n: tok = b.tokens[i] tokid = tok.id # If we are not looking for the start of a new # type/var/func, then skip over tokens until # we find our terminator, managing the depth of # accolades as we go. if state > 0: terminator = False if tokid == '{': depth += 1 elif tokid == '}': if depth > 0: depth -= 1 if (depth == 0) and (state == 3): terminator = True elif tokid == ';' and depth == 0: terminator = True if terminator: # we found the terminator state = 0 if skipTokens: skipTokens = False first = i + 1 i += 1 continue # Is it a new type definition, then start recording it if tok.id in ['struct', 'typedef', 'enum', 'union', '__extension__']: state = 1 i += 1 continue # Is it a variable or function definition. If so, first # try to determine which type it is, and also extract # its name. # # We're going to parse the next tokens of the same block # until we find a semi-column or a left parenthesis. # # The semi-column corresponds to a variable definition, # the left-parenthesis to a function definition. # # We also assume that the var/func name is the last # identifier before the terminator. # j = i + 1 ident = "" while j < n: tokid = b.tokens[j].id if tokid == '(': # a function declaration state = 3 break elif tokid == ';': # a variable declaration state = 2 break if b.tokens[j].kind == TokenKind.IDENTIFIER: ident = b.tokens[j].id j += 1 if j >= n: # This can only happen when the declaration # does not end on the current block (e.g. with # a directive mixed inside it. # # We will treat it as malformed because # it's very hard to recover from this case # without making our parser much more # complex. # logging.debug("### skip unterminated static '%s'", ident) break if ident in knownStatics: logging.debug("### keep var/func '%s': %s", ident, repr(b.tokens[i:j])) else: # We're going to skip the tokens for this declaration logging.debug("### skip var/func '%s': %s", ident, repr(b.tokens[i:j])) if i > first: blocks2.append(Block(b.tokens[first:i])) skipTokens = True first = n i += 1 if i > first: # print "### final '%s'" % repr(b.tokens[first:i]) blocks2.append(Block(b.tokens[first:i])) self.blocks = blocks2 def replaceTokens(self, replacements): """Replace tokens according to the given dict.""" for b in self.blocks: made_change = False if b.isInclude() is None: for tok in b.tokens: if tok.kind == TokenKind.IDENTIFIER: if tok.id in replacements: tok.id = replacements[tok.id] made_change = True if b.isDefine() and b.define_id in replacements: b.define_id = replacements[b.define_id] made_change = True if made_change and b.isIf(): # Keep 'expr' in sync with 'tokens'. b.expr = CppExpr(b.tokens) def strip_space(s): """Strip out redundant space in a given string.""" # NOTE: It ought to be more clever to not destroy spaces in string tokens. replacements = {' . ': '.', ' [': '[', '[ ': '[', ' ]': ']', '( ': '(', ' )': ')', ' ,': ',', '# ': '#', ' ;': ';', '~ ': '~', ' -> ': '->'} result = s for r in replacements: result = result.replace(r, replacements[r]) # Remove the space between function name and the parenthesis. result = re.sub(r'(\w+) \(', r'\1(', result) return result class BlockParser(object): """A class that converts an input source file into a BlockList object.""" def __init__(self, tokzer=None): """Initialize a block parser. The input source is provided through a Tokenizer object. """ self._tokzer = tokzer self._parsed = False @property def parsed(self): return self._parsed @staticmethod def _short_extent(extent): return '%d:%d - %d:%d' % (extent.start.line, extent.start.column, extent.end.line, extent.end.column) def getBlocks(self, tokzer=None): """Return all the blocks parsed.""" def consume_extent(i, tokens, extent=None, detect_change=False): """Return tokens that belong to the given extent. It parses all the tokens that follow tokens[i], until getting out of the extent. When detect_change is True, it may terminate early when detecting preprocessing directives inside the extent. """ result = [] if extent is None: extent = tokens[i].cursor.extent while i < len(tokens) and tokens[i].location in extent: t = tokens[i] if debugBlockParser: print ' ' * 2, t.id, t.kind, t.cursor.kind if (detect_change and t.cursor.extent != extent and t.cursor.kind == CursorKind.PREPROCESSING_DIRECTIVE): break result.append(t) i += 1 return (i, result) def consume_line(i, tokens): """Return tokens that follow tokens[i] in the same line.""" result = [] line = tokens[i].location.line while i < len(tokens) and tokens[i].location.line == line: if tokens[i].cursor.kind == CursorKind.PREPROCESSING_DIRECTIVE: break result.append(tokens[i]) i += 1 return (i, result) if tokzer is None: tokzer = self._tokzer tokens = tokzer.tokens blocks = [] buf = [] i = 0 while i < len(tokens): t = tokens[i] cursor = t.cursor if debugBlockParser: print ("%d: Processing [%s], kind=[%s], cursor=[%s], " "extent=[%s]" % (t.location.line, t.spelling, t.kind, cursor.kind, self._short_extent(cursor.extent))) if cursor.kind == CursorKind.PREPROCESSING_DIRECTIVE: if buf: blocks.append(Block(buf)) buf = [] j = i if j + 1 >= len(tokens): raise BadExpectedToken("### BAD TOKEN at %s" % (t.location)) directive = tokens[j+1].id if directive == 'define': if i+2 >= len(tokens): raise BadExpectedToken("### BAD TOKEN at %s" % (tokens[i].location)) # Skip '#' and 'define'. extent = tokens[i].cursor.extent i += 2 id = '' # We need to separate the id from the remaining of # the line, especially for the function-like macro. if (i + 1 < len(tokens) and tokens[i+1].id == '(' and (tokens[i].location.column + len(tokens[i].spelling) == tokens[i+1].location.column)): while i < len(tokens): id += tokens[i].id if tokens[i].spelling == ')': i += 1 break i += 1 else: id += tokens[i].id # Advance to the next token that follows the macro id i += 1 (i, ret) = consume_extent(i, tokens, extent=extent) blocks.append(Block(ret, directive=directive, lineno=t.location.line, identifier=id)) else: (i, ret) = consume_extent(i, tokens) blocks.append(Block(ret[2:], directive=directive, lineno=t.location.line)) elif cursor.kind == CursorKind.INCLUSION_DIRECTIVE: if buf: blocks.append(Block(buf)) buf = [] directive = tokens[i+1].id (i, ret) = consume_extent(i, tokens) blocks.append(Block(ret[2:], directive=directive, lineno=t.location.line)) elif cursor.kind == CursorKind.VAR_DECL: if buf: blocks.append(Block(buf)) buf = [] (i, ret) = consume_extent(i, tokens, detect_change=True) buf += ret elif cursor.kind == CursorKind.FUNCTION_DECL: if buf: blocks.append(Block(buf)) buf = [] (i, ret) = consume_extent(i, tokens, detect_change=True) buf += ret else: (i, ret) = consume_line(i, tokens) buf += ret if buf: blocks.append(Block(buf)) # _parsed=True indicates a successful parsing, although may result an # empty BlockList. self._parsed = True return BlockList(blocks) def parse(self, tokzer): return self.getBlocks(tokzer) def parseFile(self, path): return self.getBlocks(CppFileTokenizer(path)) def test_block_parsing(lines, expected): """Helper method to test the correctness of BlockParser.parse.""" blocks = BlockParser().parse(CppStringTokenizer('\n'.join(lines))) if len(blocks) != len(expected): raise BadExpectedToken("BlockParser.parse() returned '%s' expecting " "'%s'" % (str(blocks), repr(expected))) for n in range(len(blocks)): if str(blocks[n]) != expected[n]: raise BadExpectedToken("BlockParser.parse()[%d] is '%s', " "expecting '%s'" % (n, str(blocks[n]), expected[n])) def test_BlockParser(): test_block_parsing(["#error hello"], ["#error hello"]) test_block_parsing(["foo", "", "bar"], ["foo bar"]) # We currently cannot handle the following case with libclang properly. # Fortunately it doesn't appear in current headers. # test_block_parsing(["foo", " # ", "bar"], ["foo", "bar"]) test_block_parsing(["foo", " # /* ahah */ if defined(__KERNEL__) /* more */", "bar", "#endif"], ["foo", "#ifdef __KERNEL__", "bar", "#endif"]) ################################################################################ ################################################################################ ##### ##### ##### B L O C K L I S T O P T I M I Z A T I O N ##### ##### ##### ################################################################################ ################################################################################ def remove_macro_defines(blocks, excludedMacros=None): """Remove macro definitions like #define <macroName> ....""" if excludedMacros is None: excludedMacros = set() result = [] for b in blocks: macroName = b.isDefine() if macroName is None or macroName not in excludedMacros: result.append(b) return result def find_matching_endif(blocks, i): """Traverse the blocks to find out the matching #endif.""" n = len(blocks) depth = 1 while i < n: if blocks[i].isDirective(): dir_ = blocks[i].directive if dir_ in ["if", "ifndef", "ifdef"]: depth += 1 elif depth == 1 and dir_ in ["else", "elif"]: return i elif dir_ == "endif": depth -= 1 if depth == 0: return i i += 1 return i def optimize_if01(blocks): """Remove the code between #if 0 .. #endif in a list of CppBlocks.""" i = 0 n = len(blocks) result = [] while i < n: j = i while j < n and not blocks[j].isIf(): j += 1 if j > i: logging.debug("appending lines %d to %d", blocks[i].lineno, blocks[j-1].lineno) result += blocks[i:j] if j >= n: break expr = blocks[j].expr r = expr.toInt() if r is None: result.append(blocks[j]) i = j + 1 continue if r == 0: # if 0 => skip everything until the corresponding #endif j = find_matching_endif(blocks, j + 1) if j >= n: # unterminated #if 0, finish here break dir_ = blocks[j].directive if dir_ == "endif": logging.debug("remove 'if 0' .. 'endif' (lines %d to %d)", blocks[i].lineno, blocks[j].lineno) i = j + 1 elif dir_ == "else": # convert 'else' into 'if 1' logging.debug("convert 'if 0' .. 'else' into 'if 1' (lines %d " "to %d)", blocks[i].lineno, blocks[j-1].lineno) blocks[j].directive = "if" blocks[j].expr = CppExpr(CppStringTokenizer("1").tokens) i = j elif dir_ == "elif": # convert 'elif' into 'if' logging.debug("convert 'if 0' .. 'elif' into 'if'") blocks[j].directive = "if" i = j continue # if 1 => find corresponding endif and remove/transform them k = find_matching_endif(blocks, j + 1) if k >= n: # unterminated #if 1, finish here logging.debug("unterminated 'if 1'") result += blocks[j+1:k] break dir_ = blocks[k].directive if dir_ == "endif": logging.debug("convert 'if 1' .. 'endif' (lines %d to %d)", blocks[j].lineno, blocks[k].lineno) result += optimize_if01(blocks[j+1:k]) i = k + 1 elif dir_ == "else": # convert 'else' into 'if 0' logging.debug("convert 'if 1' .. 'else' (lines %d to %d)", blocks[j].lineno, blocks[k].lineno) result += optimize_if01(blocks[j+1:k]) blocks[k].directive = "if" blocks[k].expr = CppExpr(CppStringTokenizer("0").tokens) i = k elif dir_ == "elif": # convert 'elif' into 'if 0' logging.debug("convert 'if 1' .. 'elif' (lines %d to %d)", blocks[j].lineno, blocks[k].lineno) result += optimize_if01(blocks[j+1:k]) blocks[k].expr = CppExpr(CppStringTokenizer("0").tokens) i = k return result def test_optimizeAll(): text = """\ #if 1 #define GOOD_1 #endif #if 0 #define BAD_2 #define BAD_3 #endif #if 1 #define GOOD_2 #else #define BAD_4 #endif #if 0 #define BAD_5 #else #define GOOD_3 #endif #if defined(__KERNEL__) #define BAD_KERNEL #endif #if defined(__KERNEL__) || !defined(__GLIBC__) || (__GLIBC__ < 2) #define X #endif #ifndef SIGRTMAX #define SIGRTMAX 123 #endif /* SIGRTMAX */ #if 0 #if 1 #define BAD_6 #endif #endif\ """ expected = """\ #define GOOD_1 #define GOOD_2 #define GOOD_3 #if !defined(__GLIBC__) || __GLIBC__ < 2 #define X #endif #ifndef __SIGRTMAX #define __SIGRTMAX 123 #endif\ """ out = utils.StringOutput() blocks = BlockParser().parse(CppStringTokenizer(text)) blocks.replaceTokens(kernel_token_replacements) blocks.optimizeAll({"__KERNEL__": kCppUndefinedMacro}) blocks.write(out) if out.get() != expected: print "[FAIL]: macro optimization failed\n" print "<<<< expecting '", print expected, print "'\n>>>> result '", print out.get(), print "'\n----" global failure_count failure_count += 1 def runUnitTests(): """Always run all unit tests for this program.""" test_CppTokenizer() test_CppExpr() test_optimizeAll() test_BlockParser() failure_count = 0 runUnitTests() if failure_count != 0: utils.panic("Unit tests failed in cpp.py.\n")