vendor/llvm/llvm-trunk-r290819

1 files changed, 109 insertions, 31 deletions

diff --git a/lib/Support/StringRef.cpp b/lib/Support/StringRef.cpp
index 8a9da5edca84..d81250e48dde 100644
--- a/lib/Support/StringRef.cpp
+++ b/lib/Support/StringRef.cpp
@@ -69,6 +69,11 @@ bool StringRef::endswith_lower(StringRef Suffix) const {
       ascii_strncasecmp(end() - Suffix.Length, Suffix.Data, Suffix.Length) == 0;
 }
 
+size_t StringRef::find_lower(char C, size_t From) const {
+  char L = ascii_tolower(C);
+  return find_if([L](char D) { return ascii_tolower(D) == L; }, From);
+}
+
 /// 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) {
@@ -143,16 +148,20 @@ size_t StringRef::find(StringRef Str, size_t From) const {
   if (From > Length)
     return npos;
 
+  const char *Start = Data + From;
+  size_t Size = Length - From;
+
   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;
+  if (N == 1) {
+    const char *Ptr = (const char *)::memchr(Start, Needle[0], Size);
+    return Ptr == nullptr ? npos : Ptr - Data;
+  }
 
-  const char *Start = Data + From;
   const char *Stop = Start + (Size - N + 1);
 
   // For short haystacks or unsupported needles fall back to the naive algorithm
@@ -172,16 +181,40 @@ size_t StringRef::find(StringRef Str, size_t From) const {
     BadCharSkip[(uint8_t)Str[i]] = N-1-i;
 
   do {
-    if (std::memcmp(Start, Needle, N) == 0)
-      return Start - Data;
+    uint8_t Last = Start[N - 1];
+    if (LLVM_UNLIKELY(Last == (uint8_t)Needle[N - 1]))
+      if (std::memcmp(Start, Needle, N - 1) == 0)
+        return Start - Data;
 
     // Otherwise skip the appropriate number of bytes.
-    Start += BadCharSkip[(uint8_t)Start[N-1]];
+    Start += BadCharSkip[Last];
   } while (Start < Stop);
 
   return npos;
 }
 
+size_t StringRef::find_lower(StringRef Str, size_t From) const {
+  StringRef This = substr(From);
+  while (This.size() >= Str.size()) {
+    if (This.startswith_lower(Str))
+      return From;
+    This = This.drop_front();
+    ++From;
+  }
+  return npos;
+}
+
+size_t StringRef::rfind_lower(char C, size_t From) const {
+  From = std::min(From, Length);
+  size_t i = From;
+  while (i != 0) {
+    --i;
+    if (ascii_tolower(Data[i]) == ascii_tolower(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
@@ -198,6 +231,18 @@ size_t StringRef::rfind(StringRef Str) const {
   return npos;
 }
 
+size_t StringRef::rfind_lower(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_lower(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.
 ///
@@ -351,6 +396,9 @@ size_t StringRef::count(StringRef Str) const {
 }
 
 static unsigned GetAutoSenseRadix(StringRef &Str) {
+  if (Str.empty())
+    return 10;
+
   if (Str.startswith("0x") || Str.startswith("0X")) {
     Str = Str.substr(2);
     return 16;
@@ -366,17 +414,16 @@ static unsigned GetAutoSenseRadix(StringRef &Str) {
     return 8;
   }
 
-  if (Str.startswith("0"))
+  if (Str[0] == '0' && Str.size() > 1 && ascii_isdigit(Str[1])) {
+    Str = Str.substr(1);
     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) {
+bool llvm::consumeUnsignedInteger(StringRef &Str, unsigned Radix,
+                                  unsigned long long &Result) {
   // Autosense radix if not specified.
   if (Radix == 0)
     Radix = GetAutoSenseRadix(Str);
@@ -385,44 +432,51 @@ bool llvm::getAsUnsignedInteger(StringRef Str, unsigned Radix,
   if (Str.empty()) return true;
 
   // Parse all the bytes of the string given this radix.  Watch for overflow.
+  StringRef Str2 = Str;
   Result = 0;
-  while (!Str.empty()) {
+  while (!Str2.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;
+    if (Str2[0] >= '0' && Str2[0] <= '9')
+      CharVal = Str2[0] - '0';
+    else if (Str2[0] >= 'a' && Str2[0] <= 'z')
+      CharVal = Str2[0] - 'a' + 10;
+    else if (Str2[0] >= 'A' && Str2[0] <= 'Z')
+      CharVal = Str2[0] - 'A' + 10;
     else
-      return true;
+      break;
 
-    // If the parsed value is larger than the integer radix, the string is
-    // invalid.
+    // If the parsed value is larger than the integer radix, we cannot
+    // consume any more characters.
     if (CharVal >= Radix)
-      return true;
+      break;
 
     // Add in this character.
     unsigned long long PrevResult = Result;
-    Result = Result*Radix+CharVal;
+    Result = Result * Radix + CharVal;
 
     // Check for overflow by shifting back and seeing if bits were lost.
-    if (Result/Radix < PrevResult)
+    if (Result / Radix < PrevResult)
       return true;
 
-    Str = Str.substr(1);
+    Str2 = Str2.substr(1);
   }
 
+  // We consider the operation a failure if no characters were consumed
+  // successfully.
+  if (Str.size() == Str2.size())
+    return true;
+
+  Str = Str2;
   return false;
 }
 
-bool llvm::getAsSignedInteger(StringRef Str, unsigned Radix,
-                              long long &Result) {
+bool llvm::consumeSignedInteger(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) ||
+    if (consumeUnsignedInteger(Str, Radix, ULLVal) ||
         // Check for value so large it overflows a signed value.
         (long long)ULLVal < 0)
       return true;
@@ -431,17 +485,41 @@ bool llvm::getAsSignedInteger(StringRef Str, unsigned Radix,
   }
 
   // Get the positive part of the value.
-  if (getAsUnsignedInteger(Str.substr(1), Radix, ULLVal) ||
+  StringRef Str2 = Str.drop_front(1);
+  if (consumeUnsignedInteger(Str2, 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;
 
+  Str = Str2;
   Result = -ULLVal;
   return false;
 }
 
+/// 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) {
+  if (consumeUnsignedInteger(Str, Radix, Result))
+    return true;
+
+  // For getAsUnsignedInteger, we require the whole string to be consumed or
+  // else we consider it a failure.
+  return !Str.empty();
+}
+
+bool llvm::getAsSignedInteger(StringRef Str, unsigned Radix,
+                              long long &Result) {
+  if (consumeSignedInteger(Str, Radix, Result))
+    return true;
+
+  // For getAsSignedInteger, we require the whole string to be consumed or else
+  // we consider it a failure.
+  return !Str.empty();
+}
+
 bool StringRef::getAsInteger(unsigned Radix, APInt &Result) const {
   StringRef Str = *this;