mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-24 19:52:54 +01:00
436 lines
15 KiB
C++
436 lines
15 KiB
C++
//===--- StringRef.h - Constant String Reference Wrapper --------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_ADT_STRINGREF_H
|
|
#define LLVM_ADT_STRINGREF_H
|
|
|
|
#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.
|
|
///
|
|
/// This class does not own the string data, it is expected to be used in
|
|
/// situations where the character data resides in some other buffer, whose
|
|
/// lifetime extends past that of the StringRef. For this reason, it is not in
|
|
/// general safe to store a StringRef.
|
|
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.
|
|
const char *Data;
|
|
|
|
/// 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 an empty string ref.
|
|
/*implicit*/ StringRef() : Data(0), Length(0) {}
|
|
|
|
/// Construct a string ref from a cstring.
|
|
/*implicit*/ StringRef(const char *Str)
|
|
: Data(Str), Length(::strlen(Str)) {}
|
|
|
|
/// Construct a string ref from a pointer and 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.data()), Length(Str.length()) {}
|
|
|
|
/// @}
|
|
/// @name Iterators
|
|
/// @{
|
|
|
|
iterator begin() const { return Data; }
|
|
|
|
iterator end() const { return Data + Length; }
|
|
|
|
/// @}
|
|
/// @name String Operations
|
|
/// @{
|
|
|
|
/// data - Get a pointer to the start of the string (which may not be null
|
|
/// terminated).
|
|
const char *data() const { return Data; }
|
|
|
|
/// empty - Check if the string is empty.
|
|
bool empty() const { return Length == 0; }
|
|
|
|
/// 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() 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(StringRef RHS) const {
|
|
// Check the prefix for a mismatch.
|
|
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.
|
|
if (Length == RHS.Length)
|
|
return 0;
|
|
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).
|
|
///
|
|
/// \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);
|
|
|
|
/// str - Get the contents as an std::string.
|
|
std::string str() const {
|
|
if (Data == 0) return "";
|
|
return std::string(Data, Length);
|
|
}
|
|
|
|
/// @}
|
|
/// @name Operator Overloads
|
|
/// @{
|
|
|
|
char operator[](size_t Index) const {
|
|
assert(Index < Length && "Invalid index!");
|
|
return Data[Index];
|
|
}
|
|
|
|
/// @}
|
|
/// @name Type Conversions
|
|
/// @{
|
|
|
|
operator std::string() const {
|
|
return str();
|
|
}
|
|
|
|
/// @}
|
|
/// @name String Predicates
|
|
/// @{
|
|
|
|
/// 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 = 0) const { return find(C); }
|
|
|
|
/// 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 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 = min(Start, Length);
|
|
return StringRef(Data + Start, min(N, Length - Start));
|
|
}
|
|
|
|
/// 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==(StringRef LHS, StringRef RHS) {
|
|
return LHS.equals(RHS);
|
|
}
|
|
|
|
inline bool operator!=(StringRef LHS, StringRef RHS) {
|
|
return !(LHS == RHS);
|
|
}
|
|
|
|
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>(StringRef LHS, StringRef RHS) {
|
|
return LHS.compare(RHS) == 1;
|
|
}
|
|
|
|
inline bool operator>=(StringRef LHS, StringRef RHS) {
|
|
return LHS.compare(RHS) != -1;
|
|
}
|
|
|
|
/// @}
|
|
|
|
}
|
|
|
|
#endif
|