#include <cassert>
#include <cstring>
+#include <utility>
#include <string>
namespace llvm {
+ template<typename T>
+ class SmallVectorImpl;
+ class APInt;
/// StringRef - Represent a constant reference to a string, i.e. a character
/// array and a length, which need not be null terminated.
class StringRef {
public:
typedef const char *iterator;
- static const size_t npos = std::string::npos;
+ 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.
/// 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; }
+
public:
/// @name Constructors
/// @{
/*implicit*/ StringRef() : Data(0), Length(0) {}
/// Construct a string ref from a cstring.
- /*implicit*/ StringRef(const char *Str)
+ /*implicit*/ StringRef(const char *Str)
: Data(Str), Length(::strlen(Str)) {}
-
+
/// 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) {}
/// 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
/// size - Get the string size.
size_t size() const { return Length; }
+ /// front - Get the first character in the string.
+ char front() const {
+ assert(!empty());
+ return Data[0];
+ }
+
+ /// back - Get the last character in the string.
+ char back() const {
+ assert(!empty());
+ return Data[Length-1];
+ }
+
/// equals - Check for string equality, this is more efficient than
- /// compare() in when the relative ordering of inequal strings isn't needed.
- bool equals(const StringRef &RHS) const {
- return (Length == RHS.Length &&
- memcmp(Data, RHS.Data, Length) == 0);
+ /// compare() when the relative ordering of inequal strings isn't needed.
+ bool equals(StringRef RHS) const {
+ return (Length == RHS.Length &&
+ memcmp(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 = memcmp(Data, RHS.Data, min(Length, RHS.Length)))
return Res < 0 ? -1 : 1;
// Otherwise the prefixes match, so we only need to check the lengths.
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];
}
/// @}
}
/// @}
- /// @name Utility Functions
+ /// @name String Predicates
/// @{
- /// substr - Return a reference to a substring of this object.
+ /// startswith - Check if this string starts with the given \arg Prefix.
+ bool startswith(StringRef Prefix) const {
+ return Length >= Prefix.Length &&
+ memcmp(Data, Prefix.Data, Prefix.Length) == 0;
+ }
+
+ /// endswith - Check if this string ends with the given \arg Suffix.
+ bool endswith(StringRef Suffix) const {
+ return Length >= Suffix.Length &&
+ memcmp(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0;
+ }
+
+ /// @}
+ /// @name String Searching
+ /// @{
+
+ /// find - Search for the first character \arg C in the string.
+ ///
+ /// \return - The index of the first occurrence of \arg C, or npos if not
+ /// found.
+ 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 first string \arg Str in the string.
+ ///
+ /// \return - The index of the first occurrence of \arg Str, or npos if not
+ /// found.
+ 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;
+
+ /// @}
+ /// @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.
+ ///
+ bool getAsInteger(unsigned Radix, long long &Result) const;
+ bool getAsInteger(unsigned Radix, unsigned long long &Result) const;
+ bool getAsInteger(unsigned Radix, int &Result) const;
+ bool getAsInteger(unsigned Radix, unsigned &Result) const;
+
+ // TODO: Provide overloads for int/unsigned that check for overflow.
+
+ /// 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 Substring Operations
+ /// @{
+
+ /// substr - Return a reference to the substring from [Start, Start + N).
///
/// \param Start - The index of the starting character in the substring; if
- /// the index is greater than the length of the string then the empty
- /// substring will be returned.
+ /// the index is npos or greater than the length of the string then the
+ /// empty substring will be returned.
///
/// \param N - The number of characters to included in the substring. If N
/// 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));
}
- /// startswith - Check if this string starts with the given \arg Prefix.
- bool startswith(const StringRef &Prefix) const {
- return substr(0, Prefix.Length).equals(Prefix);
+ /// slice - Return a reference to the substring from [Start, End).
+ ///
+ /// \param Start - The index of the starting character in the substring; if
+ /// the index is npos or greater than the length of the string then the
+ /// empty substring will be returned.
+ ///
+ /// \param End - The index following the last character to include in the
+ /// substring. If this is npos, or less than \arg Start, or exceeds the
+ /// 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 = min(Start, Length);
+ End = min(max(Start, End), Length);
+ return StringRef(Data + Start, End - Start);
+ }
+
+ /// 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)
+ /// 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 character to split on.
+ /// \return - The split substrings.
+ std::pair<StringRef, StringRef> split(char 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+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<StringRef, StringRef> 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<StringRef> &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<StringRef, StringRef> 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));
}
/// @}
/// @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<=(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 bool operator>=(StringRef LHS, StringRef RHS) {
+ return LHS.compare(RHS) != -1;
}
/// @}
projects / oota-llvm.git / blobdiff