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-rw-r--r--lib/Support/StringRef.cpp188
1 files changed, 188 insertions, 0 deletions
diff --git a/lib/Support/StringRef.cpp b/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"
+using namespace llvm;
+
+// MSVC emits references to this into the translation units which reference it.
+#ifndef _MSC_VER
+const size_t StringRef::npos;
+#endif
+
+//===----------------------------------------------------------------------===//
+// String Searching
+//===----------------------------------------------------------------------===//
+
+
+/// 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
+/// found.
+size_t StringRef::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))
+ return i;
+ return npos;
+}
+
+/// 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
+/// found.
+size_t StringRef::rfind(const 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 from the string 'Chars' in the
+/// current string or return npos if not in string.
+StringRef::size_type StringRef::find_first_of(StringRef Chars) const {
+ for (size_type i = 0, e = Length; i != e; ++i)
+ if (Chars.find(Data[i]) != npos)
+ return i;
+ return npos;
+}
+
+/// find_first_not_of - Find the first character in the string that is not
+/// in the string 'Chars' or return npos if all are in string. Same as find.
+StringRef::size_type StringRef::find_first_not_of(StringRef Chars) const {
+ for (size_type i = 0, e = Length; i != e; ++i)
+ if (Chars.find(Data[i]) == npos)
+ return i;
+ return npos;
+}
+
+
+//===----------------------------------------------------------------------===//
+// Helpful Algorithms
+//===----------------------------------------------------------------------===//
+
+/// count - Return the number of non-overlapped occurrences of \arg Str in
+/// the string.
+size_t StringRef::count(const 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;
+}
+
+/// GetAsUnsignedInteger - Workhorse method that converts a integer character
+/// sequence of radix up to 36 to an unsigned long long value.
+static bool GetAsUnsignedInteger(StringRef Str, unsigned Radix,
+ unsigned long long &Result) {
+ // Autosense radix if not specified.
+ if (Radix == 0) {
+ if (Str.startswith("0x")) {
+ Str = Str.substr(2);
+ Radix = 16;
+ } else if (Str.startswith("0b")) {
+ Str = Str.substr(2);
+ Radix = 2;
+ } else if (Str.startswith("0"))
+ Radix = 8;
+ else
+ Radix = 10;
+ }
+
+ // 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.
+ if (Result < PrevResult)
+ return true;
+
+ Str = Str.substr(1);
+ }
+
+ return false;
+}
+
+bool StringRef::getAsInteger(unsigned Radix, unsigned long long &Result) const {
+ return GetAsUnsignedInteger(*this, Radix, Result);
+}
+
+
+bool StringRef::getAsInteger(unsigned Radix, long long &Result) const {
+ unsigned long long ULLVal;
+
+ // Handle positive strings first.
+ if (empty() || front() != '-') {
+ if (GetAsUnsignedInteger(*this, 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(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, int &Result) const {
+ long long Val;
+ if (getAsInteger(Radix, Val) ||
+ (int)Val != Val)
+ return true;
+ Result = Val;
+ return false;
+}
+
+bool StringRef::getAsInteger(unsigned Radix, unsigned &Result) const {
+ unsigned long long Val;
+ if (getAsInteger(Radix, Val) ||
+ (unsigned)Val != Val)
+ return true;
+ Result = Val;
+ return false;
+}
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