vendor/llvm/llvm-r84119

1 files changed, 188 insertions, 0 deletions

diff --git a/lib/Support/StringRef.cpp b/lib/Support/StringRef.cpp
new file mode 100644
index 000000000000..deaa19efe998
--- /dev/null
+++ b/lib/Support/StringRef.cpp
@@ -0,0 +1,188 @@
+//===-- 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;
+}