X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FStringRef.h;h=cd846031c5a02030e0b269033e89b51e32955fff;hb=58aae3841cb054e909d6b5251399bfd7478653bc;hp=40689a98870a186b742516a1b9ee167928ef3caf;hpb=ac55b85438da378bab227fd34167bb0c4a9249aa;p=oota-llvm.git diff --git a/include/llvm/ADT/StringRef.h b/include/llvm/ADT/StringRef.h index 40689a98870..cd846031c5a 100644 --- a/include/llvm/ADT/StringRef.h +++ b/include/llvm/ADT/StringRef.h @@ -10,12 +10,27 @@ #ifndef LLVM_ADT_STRINGREF_H #define LLVM_ADT_STRINGREF_H +#include "llvm/Support/type_traits.h" + #include #include #include +#include #include +#include namespace llvm { + template + class SmallVectorImpl; + class APInt; + class hash_code; + class StringRef; + + /// Helper functions for StringRef::getAsInteger. + bool getAsUnsignedInteger(StringRef Str, unsigned Radix, + unsigned long long &Result); + + bool getAsSignedInteger(StringRef Str, unsigned Radix, long long &Result); /// StringRef - Represent a constant reference to a string, i.e. a character /// array and a length, which need not be null terminated. @@ -27,7 +42,9 @@ namespace llvm { class StringRef { public: typedef const char *iterator; + typedef const char *const_iterator; static const size_t npos = ~size_t(0); + typedef size_t size_type; private: /// The start of the string, in an external buffer. @@ -36,6 +53,19 @@ namespace llvm { /// The length of the string. size_t Length; + // Workaround PR5482: nearly all gcc 4.x miscompile StringRef and std::min() + // Changing the arg of min to be an integer, instead of a reference to an + // integer works around this bug. + static size_t min(size_t a, size_t b) { return a < b ? a : b; } + static size_t max(size_t a, size_t b) { return a > b ? a : b; } + + // Workaround memcmp issue with null pointers (undefined behavior) + // by providing a specialized version + static int compareMemory(const char *Lhs, const char *Rhs, size_t Length) { + if (Length == 0) { return 0; } + return ::memcmp(Lhs,Rhs,Length); + } + public: /// @name Constructors /// @{ @@ -44,16 +74,22 @@ namespace llvm { /*implicit*/ StringRef() : Data(0), Length(0) {} /// Construct a string ref from a cstring. - /*implicit*/ StringRef(const char *Str) - : Data(Str), Length(::strlen(Str)) {} - + /*implicit*/ StringRef(const char *Str) + : Data(Str) { + assert(Str && "StringRef cannot be built from a NULL argument"); + Length = ::strlen(Str); // invoking strlen(NULL) is undefined behavior + } + /// Construct a string ref from a pointer and length. - /*implicit*/ StringRef(const char *_Data, unsigned _Length) - : Data(_Data), Length(_Length) {} + /*implicit*/ StringRef(const char *data, size_t length) + : Data(data), Length(length) { + assert((data || length == 0) && + "StringRef cannot be built from a NULL argument with non-null length"); + } /// Construct a string ref from an std::string. - /*implicit*/ StringRef(const std::string &Str) - : Data(Str.c_str()), Length(Str.length()) {} + /*implicit*/ StringRef(const std::string &Str) + : Data(Str.data()), Length(Str.length()) {} /// @} /// @name Iterators @@ -82,7 +118,7 @@ namespace llvm { assert(!empty()); return Data[0]; } - + /// back - Get the last character in the string. char back() const { assert(!empty()); @@ -91,16 +127,21 @@ namespace llvm { /// equals - Check for string equality, this is more efficient than /// compare() when the relative ordering of inequal strings isn't needed. - bool equals(const StringRef &RHS) const { - return (Length == RHS.Length && - memcmp(Data, RHS.Data, RHS.Length) == 0); + bool equals(StringRef RHS) const { + return (Length == RHS.Length && + compareMemory(Data, RHS.Data, RHS.Length) == 0); + } + + /// equals_lower - Check for string equality, ignoring case. + bool equals_lower(StringRef RHS) const { + return Length == RHS.Length && compare_lower(RHS) == 0; } /// compare - Compare two strings; the result is -1, 0, or 1 if this string /// is lexicographically less than, equal to, or greater than the \arg RHS. - int compare(const StringRef &RHS) const { + int compare(StringRef RHS) const { // Check the prefix for a mismatch. - if (int Res = memcmp(Data, RHS.Data, std::min(Length, RHS.Length))) + if (int Res = compareMemory(Data, RHS.Data, min(Length, RHS.Length))) return Res < 0 ? -1 : 1; // Otherwise the prefixes match, so we only need to check the lengths. @@ -109,16 +150,47 @@ namespace llvm { return Length < RHS.Length ? -1 : 1; } + /// compare_lower - Compare two strings, ignoring case. + int compare_lower(StringRef RHS) const; + + /// compare_numeric - Compare two strings, treating sequences of digits as + /// numbers. + int compare_numeric(StringRef RHS) const; + + /// \brief Determine the edit distance between this string and another + /// string. + /// + /// \param Other the string to compare this string against. + /// + /// \param AllowReplacements whether to allow character + /// replacements (change one character into another) as a single + /// operation, rather than as two operations (an insertion and a + /// removal). + /// + /// \param MaxEditDistance If non-zero, the maximum edit distance that + /// this routine is allowed to compute. If the edit distance will exceed + /// that maximum, returns \c MaxEditDistance+1. + /// + /// \returns the minimum number of character insertions, removals, + /// or (if \p AllowReplacements is \c true) replacements needed to + /// transform one of the given strings into the other. If zero, + /// the strings are identical. + unsigned edit_distance(StringRef Other, bool AllowReplacements = true, + unsigned MaxEditDistance = 0); + /// str - Get the contents as an std::string. - std::string str() const { return std::string(Data, Length); } + std::string str() const { + if (Data == 0) return std::string(); + return std::string(Data, Length); + } /// @} /// @name Operator Overloads /// @{ - char operator[](size_t Index) const { + char operator[](size_t Index) const { assert(Index < Length && "Invalid index!"); - return Data[Index]; + return Data[Index]; } /// @} @@ -134,44 +206,173 @@ namespace llvm { /// @{ /// startswith - Check if this string starts with the given \arg Prefix. - bool startswith(const StringRef &Prefix) const { - return substr(0, Prefix.Length).equals(Prefix); + bool startswith(StringRef Prefix) const { + return Length >= Prefix.Length && + compareMemory(Data, Prefix.Data, Prefix.Length) == 0; } /// endswith - Check if this string ends with the given \arg Suffix. - bool endswith(const StringRef &Suffix) const { - return slice(size() - Suffix.Length, size()).equals(Suffix); + bool endswith(StringRef Suffix) const { + return Length >= Suffix.Length && + compareMemory(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0; } /// @} /// @name String Searching /// @{ - /// find - Search for the character \arg C in the string. + /// find - Search for the first character \arg C in the string. /// - /// \return - The index of the first occurence of \arg C, or npos if not + /// \return - The index of the first occurrence of \arg C, or npos if not /// found. - size_t find(char C) const { - for (size_t i = 0, e = Length; i != e; ++i) + size_t find(char C, size_t From = 0) const { + for (size_t i = min(From, Length), e = Length; i != e; ++i) if (Data[i] == C) return i; return npos; } - /// find - Search for the string \arg Str in the string. + /// find - Search for the first string \arg Str in the string. /// - /// \return - The index of the first occurence of \arg Str, or npos if not + /// \return - The index of the first occurrence of \arg Str, or npos if not /// found. - size_t find(const StringRef &Str) const { - size_t N = Str.size(); - if (N > Length) - return npos; - for (size_t i = 0, e = Length - N + 1; i != e; ++i) - if (substr(i, N).equals(Str)) + size_t find(StringRef Str, size_t From = 0) const; + + /// rfind - Search for the last character \arg C in the string. + /// + /// \return - The index of the last occurrence of \arg C, or npos if not + /// found. + size_t rfind(char C, size_t From = npos) const { + From = min(From, Length); + size_t i = From; + while (i != 0) { + --i; + if (Data[i] == C) return i; + } return npos; } + /// rfind - Search for the last string \arg Str in the string. + /// + /// \return - The index of the last occurrence of \arg Str, or npos if not + /// found. + size_t rfind(StringRef Str) const; + + /// find_first_of - Find the first character in the string that is \arg C, + /// or npos if not found. Same as find. + size_type find_first_of(char C, size_t From = 0) const { + return find(C, From); + } + + /// find_first_of - Find the first character in the string that is in \arg + /// Chars, or npos if not found. + /// + /// Note: O(size() + Chars.size()) + size_type find_first_of(StringRef Chars, size_t From = 0) const; + + /// find_first_not_of - Find the first character in the string that is not + /// \arg C or npos if not found. + size_type find_first_not_of(char C, size_t From = 0) const; + + /// find_first_not_of - Find the first character in the string that is not + /// in the string \arg Chars, or npos if not found. + /// + /// Note: O(size() + Chars.size()) + size_type find_first_not_of(StringRef Chars, size_t From = 0) const; + + /// find_last_of - Find the last character in the string that is \arg C, or + /// npos if not found. + size_type find_last_of(char C, size_t From = npos) const { + return rfind(C, From); + } + + /// find_last_of - Find the last character in the string that is in \arg C, + /// or npos if not found. + /// + /// Note: O(size() + Chars.size()) + size_type find_last_of(StringRef Chars, size_t From = npos) const; + + /// find_last_not_of - Find the last character in the string that is not + /// \arg C, or npos if not found. + size_type find_last_not_of(char C, size_t From = npos) const; + + /// find_last_not_of - Find the last character in the string that is not in + /// \arg Chars, or npos if not found. + /// + /// Note: O(size() + Chars.size()) + size_type find_last_not_of(StringRef Chars, size_t From = npos) const; + + /// @} + /// @name Helpful Algorithms + /// @{ + + /// count - Return the number of occurrences of \arg C in the string. + size_t count(char C) const { + size_t Count = 0; + for (size_t i = 0, e = Length; i != e; ++i) + if (Data[i] == C) + ++Count; + return Count; + } + + /// count - Return the number of non-overlapped occurrences of \arg Str in + /// the string. + size_t count(StringRef Str) const; + + /// getAsInteger - Parse the current string as an integer of the specified + /// radix. If Radix is specified as zero, this does radix autosensing using + /// extended C rules: 0 is octal, 0x is hex, 0b is binary. + /// + /// If the string is invalid or if only a subset of the string is valid, + /// this returns true to signify the error. The string is considered + /// erroneous if empty or if it overflows T. + /// + template + typename enable_if_c::is_signed, bool>::type + getAsInteger(unsigned Radix, T &Result) const { + long long LLVal; + if (getAsSignedInteger(*this, Radix, LLVal) || + static_cast(LLVal) != LLVal) + return true; + Result = LLVal; + return false; + } + + template + typename enable_if_c::is_signed, bool>::type + getAsInteger(unsigned Radix, T &Result) const { + unsigned long long ULLVal; + if (getAsUnsignedInteger(*this, Radix, ULLVal) || + static_cast(ULLVal) != ULLVal) + return true; + Result = ULLVal; + return false; + } + + /// getAsInteger - Parse the current string as an integer of the + /// specified radix, or of an autosensed radix if the radix given + /// is 0. The current value in Result is discarded, and the + /// storage is changed to be wide enough to store the parsed + /// integer. + /// + /// Returns true if the string does not solely consist of a valid + /// non-empty number in the appropriate base. + /// + /// APInt::fromString is superficially similar but assumes the + /// string is well-formed in the given radix. + bool getAsInteger(unsigned Radix, APInt &Result) const; + + /// @} + /// @name String Operations + /// @{ + + // lower - Convert the given ASCII string to lowercase. + std::string lower() const; + + /// upper - Convert the given ASCII string to uppercase. + std::string upper() const; + /// @} /// @name Substring Operations /// @{ @@ -186,8 +387,22 @@ namespace llvm { /// exceeds the number of characters remaining in the string, the string /// suffix (starting with \arg Start) will be returned. StringRef substr(size_t Start, size_t N = npos) const { - Start = std::min(Start, Length); - return StringRef(Data + Start, std::min(N, Length - Start)); + Start = min(Start, Length); + return StringRef(Data + Start, min(N, Length - Start)); + } + + /// drop_front - Return a StringRef equal to 'this' but with the first + /// elements dropped. + StringRef drop_front(unsigned N = 1) const { + assert(size() >= N && "Dropping more elements than exist"); + return substr(N); + } + + /// drop_back - Return a StringRef equal to 'this' but with the last + /// elements dropped. + StringRef drop_back(unsigned N = 1) const { + assert(size() >= N && "Dropping more elements than exist"); + return substr(0, size()-N); } /// slice - Return a reference to the substring from [Start, End). @@ -201,12 +416,12 @@ namespace llvm { /// number of characters remaining in the string, the string suffix /// (starting with \arg Start) will be returned. StringRef slice(size_t Start, size_t End) const { - Start = std::min(Start, Length); - End = std::min(std::max(Start, End), Length); + Start = min(Start, Length); + End = min(max(Start, End), Length); return StringRef(Data + Start, End - Start); } - /// split - Split into two substrings around the first occurence of a + /// split - Split into two substrings around the first occurrence of a /// separator character. /// /// If \arg Separator is in the string, then the result is a pair (LHS, RHS) @@ -223,38 +438,120 @@ namespace llvm { return std::make_pair(slice(0, Idx), slice(Idx+1, npos)); } + /// split - Split into two substrings around the first occurrence of a + /// separator string. + /// + /// If \arg Separator is in the string, then the result is a pair (LHS, RHS) + /// such that (*this == LHS + Separator + RHS) is true and RHS is + /// maximal. If \arg Separator is not in the string, then the result is a + /// pair (LHS, RHS) where (*this == LHS) and (RHS == ""). + /// + /// \param Separator - The string to split on. + /// \return - The split substrings. + std::pair split(StringRef Separator) const { + size_t Idx = find(Separator); + if (Idx == npos) + return std::make_pair(*this, StringRef()); + return std::make_pair(slice(0, Idx), slice(Idx + Separator.size(), npos)); + } + + /// split - Split into substrings around the occurrences of a separator + /// string. + /// + /// Each substring is stored in \arg A. If \arg MaxSplit is >= 0, at most + /// \arg MaxSplit splits are done and consequently <= \arg MaxSplit + /// elements are added to A. + /// If \arg KeepEmpty is false, empty strings are not added to \arg A. They + /// still count when considering \arg MaxSplit + /// An useful invariant is that + /// Separator.join(A) == *this if MaxSplit == -1 and KeepEmpty == true + /// + /// \param A - Where to put the substrings. + /// \param Separator - The string to split on. + /// \param MaxSplit - The maximum number of times the string is split. + /// \param KeepEmpty - True if empty substring should be added. + void split(SmallVectorImpl &A, + StringRef Separator, int MaxSplit = -1, + bool KeepEmpty = true) const; + + /// rsplit - Split into two substrings around the last occurrence of a + /// separator character. + /// + /// If \arg Separator is in the string, then the result is a pair (LHS, RHS) + /// such that (*this == LHS + Separator + RHS) is true and RHS is + /// minimal. If \arg Separator is not in the string, then the result is a + /// pair (LHS, RHS) where (*this == LHS) and (RHS == ""). + /// + /// \param Separator - The character to split on. + /// \return - The split substrings. + std::pair rsplit(char Separator) const { + size_t Idx = rfind(Separator); + if (Idx == npos) + return std::make_pair(*this, StringRef()); + return std::make_pair(slice(0, Idx), slice(Idx+1, npos)); + } + + /// ltrim - Return string with consecutive characters in \arg Chars starting + /// from the left removed. + StringRef ltrim(StringRef Chars = " \t\n\v\f\r") const { + return drop_front(std::min(Length, find_first_not_of(Chars))); + } + + /// rtrim - Return string with consecutive characters in \arg Chars starting + /// from the right removed. + StringRef rtrim(StringRef Chars = " \t\n\v\f\r") const { + return drop_back(Length - std::min(Length, find_last_not_of(Chars) + 1)); + } + + /// trim - Return string with consecutive characters in \arg Chars starting + /// from the left and right removed. + StringRef trim(StringRef Chars = " \t\n\v\f\r") const { + return ltrim(Chars).rtrim(Chars); + } + /// @} }; /// @name StringRef Comparison Operators /// @{ - inline bool operator==(const StringRef &LHS, const StringRef &RHS) { + inline bool operator==(StringRef LHS, StringRef RHS) { return LHS.equals(RHS); } - inline bool operator!=(const StringRef &LHS, const StringRef &RHS) { + inline bool operator!=(StringRef LHS, StringRef RHS) { return !(LHS == RHS); } - - inline bool operator<(const StringRef &LHS, const StringRef &RHS) { - return LHS.compare(RHS) == -1; + + inline bool operator<(StringRef LHS, StringRef RHS) { + return LHS.compare(RHS) == -1; + } + + inline bool operator<=(StringRef LHS, StringRef RHS) { + return LHS.compare(RHS) != 1; } - inline bool operator<=(const StringRef &LHS, const StringRef &RHS) { - return LHS.compare(RHS) != 1; + inline bool operator>(StringRef LHS, StringRef RHS) { + return LHS.compare(RHS) == 1; } - inline bool operator>(const StringRef &LHS, const StringRef &RHS) { - return LHS.compare(RHS) == 1; + inline bool operator>=(StringRef LHS, StringRef RHS) { + return LHS.compare(RHS) != -1; } - inline bool operator>=(const StringRef &LHS, const StringRef &RHS) { - return LHS.compare(RHS) != -1; + inline std::string &operator+=(std::string &buffer, llvm::StringRef string) { + return buffer.append(string.data(), string.size()); } /// @} + /// \brief Compute a hash_code for a StringRef. + hash_code hash_value(StringRef S); + + // StringRefs can be treated like a POD type. + template struct isPodLike; + template <> struct isPodLike { static const bool value = true; }; + } #endif