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-rw-r--r--contrib/llvm/lib/Support/StringRef.cpp524
1 files changed, 524 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/StringRef.cpp b/contrib/llvm/lib/Support/StringRef.cpp
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+//===-- StringRef.cpp - Lightweight String References ---------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/edit_distance.h"
+#include <bitset>
+
+using namespace llvm;
+
+// MSVC emits references to this into the translation units which reference it.
+#ifndef _MSC_VER
+const size_t StringRef::npos;
+#endif
+
+static char ascii_tolower(char x) {
+ if (x >= 'A' && x <= 'Z')
+ return x - 'A' + 'a';
+ return x;
+}
+
+static char ascii_toupper(char x) {
+ if (x >= 'a' && x <= 'z')
+ return x - 'a' + 'A';
+ return x;
+}
+
+static bool ascii_isdigit(char x) {
+ return x >= '0' && x <= '9';
+}
+
+// strncasecmp() is not available on non-POSIX systems, so define an
+// alternative function here.
+static int ascii_strncasecmp(const char *LHS, const char *RHS, size_t Length) {
+ for (size_t I = 0; I < Length; ++I) {
+ unsigned char LHC = ascii_tolower(LHS[I]);
+ unsigned char RHC = ascii_tolower(RHS[I]);
+ if (LHC != RHC)
+ return LHC < RHC ? -1 : 1;
+ }
+ return 0;
+}
+
+/// compare_lower - Compare strings, ignoring case.
+int StringRef::compare_lower(StringRef RHS) const {
+ if (int Res = ascii_strncasecmp(Data, RHS.Data, std::min(Length, RHS.Length)))
+ return Res;
+ if (Length == RHS.Length)
+ return 0;
+ return Length < RHS.Length ? -1 : 1;
+}
+
+/// Check if this string starts with the given \p Prefix, ignoring case.
+bool StringRef::startswith_lower(StringRef Prefix) const {
+ return Length >= Prefix.Length &&
+ ascii_strncasecmp(Data, Prefix.Data, Prefix.Length) == 0;
+}
+
+/// Check if this string ends with the given \p Suffix, ignoring case.
+bool StringRef::endswith_lower(StringRef Suffix) const {
+ return Length >= Suffix.Length &&
+ ascii_strncasecmp(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0;
+}
+
+/// compare_numeric - Compare strings, handle embedded numbers.
+int StringRef::compare_numeric(StringRef RHS) const {
+ for (size_t I = 0, E = std::min(Length, RHS.Length); I != E; ++I) {
+ // Check for sequences of digits.
+ if (ascii_isdigit(Data[I]) && ascii_isdigit(RHS.Data[I])) {
+ // The longer sequence of numbers is considered larger.
+ // This doesn't really handle prefixed zeros well.
+ size_t J;
+ for (J = I + 1; J != E + 1; ++J) {
+ bool ld = J < Length && ascii_isdigit(Data[J]);
+ bool rd = J < RHS.Length && ascii_isdigit(RHS.Data[J]);
+ if (ld != rd)
+ return rd ? -1 : 1;
+ if (!rd)
+ break;
+ }
+ // The two number sequences have the same length (J-I), just memcmp them.
+ if (int Res = compareMemory(Data + I, RHS.Data + I, J - I))
+ return Res < 0 ? -1 : 1;
+ // Identical number sequences, continue search after the numbers.
+ I = J - 1;
+ continue;
+ }
+ if (Data[I] != RHS.Data[I])
+ return (unsigned char)Data[I] < (unsigned char)RHS.Data[I] ? -1 : 1;
+ }
+ if (Length == RHS.Length)
+ return 0;
+ return Length < RHS.Length ? -1 : 1;
+}
+
+// Compute the edit distance between the two given strings.
+unsigned StringRef::edit_distance(llvm::StringRef Other,
+ bool AllowReplacements,
+ unsigned MaxEditDistance) const {
+ return llvm::ComputeEditDistance(
+ makeArrayRef(data(), size()),
+ makeArrayRef(Other.data(), Other.size()),
+ AllowReplacements, MaxEditDistance);
+}
+
+//===----------------------------------------------------------------------===//
+// String Operations
+//===----------------------------------------------------------------------===//
+
+std::string StringRef::lower() const {
+ std::string Result(size(), char());
+ for (size_type i = 0, e = size(); i != e; ++i) {
+ Result[i] = ascii_tolower(Data[i]);
+ }
+ return Result;
+}
+
+std::string StringRef::upper() const {
+ std::string Result(size(), char());
+ for (size_type i = 0, e = size(); i != e; ++i) {
+ Result[i] = ascii_toupper(Data[i]);
+ }
+ return Result;
+}
+
+//===----------------------------------------------------------------------===//
+// String Searching
+//===----------------------------------------------------------------------===//
+
+
+/// 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 StringRef::find(StringRef Str, size_t From) const {
+ if (From > Length)
+ return npos;
+
+ const char *Needle = Str.data();
+ size_t N = Str.size();
+ if (N == 0)
+ return From;
+
+ size_t Size = Length - From;
+ if (Size < N)
+ return npos;
+
+ const char *Start = Data + From;
+ const char *Stop = Start + (Size - N + 1);
+
+ // For short haystacks or unsupported needles fall back to the naive algorithm
+ if (Size < 16 || N > 255) {
+ do {
+ if (std::memcmp(Start, Needle, N) == 0)
+ return Start - Data;
+ ++Start;
+ } while (Start < Stop);
+ return npos;
+ }
+
+ // Build the bad char heuristic table, with uint8_t to reduce cache thrashing.
+ uint8_t BadCharSkip[256];
+ std::memset(BadCharSkip, N, 256);
+ for (unsigned i = 0; i != N-1; ++i)
+ BadCharSkip[(uint8_t)Str[i]] = N-1-i;
+
+ do {
+ if (std::memcmp(Start, Needle, N) == 0)
+ return Start - Data;
+
+ // Otherwise skip the appropriate number of bytes.
+ Start += BadCharSkip[(uint8_t)Start[N-1]];
+ } while (Start < Stop);
+
+ 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 StringRef::rfind(StringRef Str) const {
+ size_t N = Str.size();
+ if (N > Length)
+ return npos;
+ for (size_t i = Length - N + 1, e = 0; i != e;) {
+ --i;
+ if (substr(i, N).equals(Str))
+ return i;
+ }
+ return npos;
+}
+
+/// 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())
+StringRef::size_type StringRef::find_first_of(StringRef Chars,
+ size_t From) const {
+ std::bitset<1 << CHAR_BIT> CharBits;
+ for (size_type i = 0; i != Chars.size(); ++i)
+ CharBits.set((unsigned char)Chars[i]);
+
+ for (size_type i = std::min(From, Length), e = Length; i != e; ++i)
+ if (CharBits.test((unsigned char)Data[i]))
+ return i;
+ return npos;
+}
+
+/// find_first_not_of - Find the first character in the string that is not
+/// \arg C or npos if not found.
+StringRef::size_type StringRef::find_first_not_of(char C, size_t From) const {
+ for (size_type i = std::min(From, Length), e = Length; i != e; ++i)
+ if (Data[i] != C)
+ return i;
+ return npos;
+}
+
+/// 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())
+StringRef::size_type StringRef::find_first_not_of(StringRef Chars,
+ size_t From) const {
+ std::bitset<1 << CHAR_BIT> CharBits;
+ for (size_type i = 0; i != Chars.size(); ++i)
+ CharBits.set((unsigned char)Chars[i]);
+
+ for (size_type i = std::min(From, Length), e = Length; i != e; ++i)
+ if (!CharBits.test((unsigned char)Data[i]))
+ return i;
+ return npos;
+}
+
+/// 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())
+StringRef::size_type StringRef::find_last_of(StringRef Chars,
+ size_t From) const {
+ std::bitset<1 << CHAR_BIT> CharBits;
+ for (size_type i = 0; i != Chars.size(); ++i)
+ CharBits.set((unsigned char)Chars[i]);
+
+ for (size_type i = std::min(From, Length) - 1, e = -1; i != e; --i)
+ if (CharBits.test((unsigned char)Data[i]))
+ return i;
+ return npos;
+}
+
+/// find_last_not_of - Find the last character in the string that is not
+/// \arg C, or npos if not found.
+StringRef::size_type StringRef::find_last_not_of(char C, size_t From) const {
+ for (size_type i = std::min(From, Length) - 1, e = -1; i != e; --i)
+ if (Data[i] != C)
+ return i;
+ return npos;
+}
+
+/// 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())
+StringRef::size_type StringRef::find_last_not_of(StringRef Chars,
+ size_t From) const {
+ std::bitset<1 << CHAR_BIT> CharBits;
+ for (size_type i = 0, e = Chars.size(); i != e; ++i)
+ CharBits.set((unsigned char)Chars[i]);
+
+ for (size_type i = std::min(From, Length) - 1, e = -1; i != e; --i)
+ if (!CharBits.test((unsigned char)Data[i]))
+ return i;
+ return npos;
+}
+
+void StringRef::split(SmallVectorImpl<StringRef> &A,
+ StringRef Separator, int MaxSplit,
+ bool KeepEmpty) const {
+ StringRef S = *this;
+
+ // Count down from MaxSplit. When MaxSplit is -1, this will just split
+ // "forever". This doesn't support splitting more than 2^31 times
+ // intentionally; if we ever want that we can make MaxSplit a 64-bit integer
+ // but that seems unlikely to be useful.
+ while (MaxSplit-- != 0) {
+ size_t Idx = S.find(Separator);
+ if (Idx == npos)
+ break;
+
+ // Push this split.
+ if (KeepEmpty || Idx > 0)
+ A.push_back(S.slice(0, Idx));
+
+ // Jump forward.
+ S = S.slice(Idx + Separator.size(), npos);
+ }
+
+ // Push the tail.
+ if (KeepEmpty || !S.empty())
+ A.push_back(S);
+}
+
+void StringRef::split(SmallVectorImpl<StringRef> &A, char Separator,
+ int MaxSplit, bool KeepEmpty) const {
+ StringRef S = *this;
+
+ // Count down from MaxSplit. When MaxSplit is -1, this will just split
+ // "forever". This doesn't support splitting more than 2^31 times
+ // intentionally; if we ever want that we can make MaxSplit a 64-bit integer
+ // but that seems unlikely to be useful.
+ while (MaxSplit-- != 0) {
+ size_t Idx = S.find(Separator);
+ if (Idx == npos)
+ break;
+
+ // Push this split.
+ if (KeepEmpty || Idx > 0)
+ A.push_back(S.slice(0, Idx));
+
+ // Jump forward.
+ S = S.slice(Idx + 1, npos);
+ }
+
+ // Push the tail.
+ if (KeepEmpty || !S.empty())
+ A.push_back(S);
+}
+
+//===----------------------------------------------------------------------===//
+// Helpful Algorithms
+//===----------------------------------------------------------------------===//
+
+/// count - Return the number of non-overlapped occurrences of \arg Str in
+/// the string.
+size_t StringRef::count(StringRef Str) const {
+ size_t Count = 0;
+ size_t N = Str.size();
+ if (N > Length)
+ return 0;
+ for (size_t i = 0, e = Length - N + 1; i != e; ++i)
+ if (substr(i, N).equals(Str))
+ ++Count;
+ return Count;
+}
+
+static unsigned GetAutoSenseRadix(StringRef &Str) {
+ if (Str.startswith("0x")) {
+ Str = Str.substr(2);
+ return 16;
+ }
+
+ if (Str.startswith("0b")) {
+ Str = Str.substr(2);
+ return 2;
+ }
+
+ if (Str.startswith("0o")) {
+ Str = Str.substr(2);
+ return 8;
+ }
+
+ if (Str.startswith("0"))
+ return 8;
+
+ return 10;
+}
+
+
+/// GetAsUnsignedInteger - Workhorse method that converts a integer character
+/// sequence of radix up to 36 to an unsigned long long value.
+bool llvm::getAsUnsignedInteger(StringRef Str, unsigned Radix,
+ unsigned long long &Result) {
+ // Autosense radix if not specified.
+ if (Radix == 0)
+ Radix = GetAutoSenseRadix(Str);
+
+ // Empty strings (after the radix autosense) are invalid.
+ if (Str.empty()) return true;
+
+ // Parse all the bytes of the string given this radix. Watch for overflow.
+ Result = 0;
+ while (!Str.empty()) {
+ unsigned CharVal;
+ if (Str[0] >= '0' && Str[0] <= '9')
+ CharVal = Str[0]-'0';
+ else if (Str[0] >= 'a' && Str[0] <= 'z')
+ CharVal = Str[0]-'a'+10;
+ else if (Str[0] >= 'A' && Str[0] <= 'Z')
+ CharVal = Str[0]-'A'+10;
+ else
+ return true;
+
+ // If the parsed value is larger than the integer radix, the string is
+ // invalid.
+ if (CharVal >= Radix)
+ return true;
+
+ // Add in this character.
+ unsigned long long PrevResult = Result;
+ Result = Result*Radix+CharVal;
+
+ // Check for overflow by shifting back and seeing if bits were lost.
+ if (Result/Radix < PrevResult)
+ return true;
+
+ Str = Str.substr(1);
+ }
+
+ return false;
+}
+
+bool llvm::getAsSignedInteger(StringRef Str, unsigned Radix,
+ long long &Result) {
+ unsigned long long ULLVal;
+
+ // Handle positive strings first.
+ if (Str.empty() || Str.front() != '-') {
+ if (getAsUnsignedInteger(Str, Radix, ULLVal) ||
+ // Check for value so large it overflows a signed value.
+ (long long)ULLVal < 0)
+ return true;
+ Result = ULLVal;
+ return false;
+ }
+
+ // Get the positive part of the value.
+ if (getAsUnsignedInteger(Str.substr(1), Radix, ULLVal) ||
+ // Reject values so large they'd overflow as negative signed, but allow
+ // "-0". This negates the unsigned so that the negative isn't undefined
+ // on signed overflow.
+ (long long)-ULLVal > 0)
+ return true;
+
+ Result = -ULLVal;
+ return false;
+}
+
+bool StringRef::getAsInteger(unsigned Radix, APInt &Result) const {
+ StringRef Str = *this;
+
+ // Autosense radix if not specified.
+ if (Radix == 0)
+ Radix = GetAutoSenseRadix(Str);
+
+ assert(Radix > 1 && Radix <= 36);
+
+ // Empty strings (after the radix autosense) are invalid.
+ if (Str.empty()) return true;
+
+ // Skip leading zeroes. This can be a significant improvement if
+ // it means we don't need > 64 bits.
+ while (!Str.empty() && Str.front() == '0')
+ Str = Str.substr(1);
+
+ // If it was nothing but zeroes....
+ if (Str.empty()) {
+ Result = APInt(64, 0);
+ return false;
+ }
+
+ // (Over-)estimate the required number of bits.
+ unsigned Log2Radix = 0;
+ while ((1U << Log2Radix) < Radix) Log2Radix++;
+ bool IsPowerOf2Radix = ((1U << Log2Radix) == Radix);
+
+ unsigned BitWidth = Log2Radix * Str.size();
+ if (BitWidth < Result.getBitWidth())
+ BitWidth = Result.getBitWidth(); // don't shrink the result
+ else if (BitWidth > Result.getBitWidth())
+ Result = Result.zext(BitWidth);
+
+ APInt RadixAP, CharAP; // unused unless !IsPowerOf2Radix
+ if (!IsPowerOf2Radix) {
+ // These must have the same bit-width as Result.
+ RadixAP = APInt(BitWidth, Radix);
+ CharAP = APInt(BitWidth, 0);
+ }
+
+ // Parse all the bytes of the string given this radix.
+ Result = 0;
+ while (!Str.empty()) {
+ unsigned CharVal;
+ if (Str[0] >= '0' && Str[0] <= '9')
+ CharVal = Str[0]-'0';
+ else if (Str[0] >= 'a' && Str[0] <= 'z')
+ CharVal = Str[0]-'a'+10;
+ else if (Str[0] >= 'A' && Str[0] <= 'Z')
+ CharVal = Str[0]-'A'+10;
+ else
+ return true;
+
+ // If the parsed value is larger than the integer radix, the string is
+ // invalid.
+ if (CharVal >= Radix)
+ return true;
+
+ // Add in this character.
+ if (IsPowerOf2Radix) {
+ Result <<= Log2Radix;
+ Result |= CharVal;
+ } else {
+ Result *= RadixAP;
+ CharAP = CharVal;
+ Result += CharAP;
+ }
+
+ Str = Str.substr(1);
+ }
+
+ return false;
+}
+
+
+// Implementation of StringRef hashing.
+hash_code llvm::hash_value(StringRef S) {
+ return hash_combine_range(S.begin(), S.end());
+}
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