#ifndef LLVM_ADT_STRINGREF_H
#define LLVM_ADT_STRINGREF_H
-#include <algorithm>
#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;
+ typedef const char *const_iterator;
static const size_t npos = ~size_t(0);
typedef size_t size_type;
/// 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
/// @{
/// Construct a string ref from a cstring.
/*implicit*/ StringRef(const char *Str)
- : Data(Str) { if (Str) Length = ::strlen(Str); else Length = 0; }
+ : Data(Str), Length(::strlen(Str)) {}
/// Construct a string ref from a pointer and length.
/*implicit*/ StringRef(const char *data, size_t length)
/// Construct a string ref from an std::string.
/*implicit*/ StringRef(const std::string &Str)
- : Data(Str.c_str()), Length(Str.length()) {}
+ : Data(Str.data()), Length(Str.length()) {}
/// @}
/// @name Iterators
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(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
/// startswith - Check if this string starts with the given \arg Prefix.
bool startswith(StringRef Prefix) const {
- return substr(0, Prefix.Length).equals(Prefix);
+ 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 slice(size() - Suffix.Length, size()).equals(Suffix);
+ return Length >= Suffix.Length &&
+ memcmp(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0;
}
/// @}
/// 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, size_t From = 0) const {
- for (size_t i = std::min(From, Length), e = Length; i != e; ++i)
+ 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 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(StringRef Str, size_t From = 0) const;
/// rfind - Search for the last character \arg C in the string.
///
- /// \return - The index of the last occurence of \arg C, or npos if not
+ /// \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 = std::min(From, Length);
+ From = min(From, Length);
size_t i = From;
while (i != 0) {
--i;
/// rfind - Search for the last string \arg Str in the string.
///
- /// \return - The index of the last occurence of \arg Str, or npos if not
+ /// \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); }
+ 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())
+ /// 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
/// 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())
+ /// Note: O(size() + Chars.size())
size_type find_first_not_of(StringRef Chars, size_t From = 0) 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
/// @{
/// 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));
}
/// slice - Return a reference to the substring from [Start, End).
/// 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)
return std::make_pair(slice(0, Idx), slice(Idx+1, npos));
}
- /// split - Split into two substrings around the first occurence of a
+ /// 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)
return std::make_pair(slice(0, Idx), slice(Idx + Separator.size(), npos));
}
- /// rsplit - Split into two substrings around the last occurence of a
+ /// 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)