Fix y-umlaut to uppercase.

R=dcarney@chromium.org
BUG=v8:2984

Review URL: https://codereview.chromium.org/59853006

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17545 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap.cc

@@ -4111,13 +4111,12 @@ MaybeObject* Heap::LookupSingleCharacterStringFromCode(uint16_t code) {
     return result;
   }
 
-  Object* result;
+  SeqTwoByteString* result;
   { MaybeObject* maybe_result = AllocateRawTwoByteString(1);
-    if (!maybe_result->ToObject(&result)) return maybe_result;
+    if (!maybe_result->To<SeqTwoByteString>(&result)) return maybe_result;
   }
-  String* answer = String::cast(result);
-  answer->Set(0, code);
-  return answer;
+  result->SeqTwoByteStringSet(0, code);
+  return result;
 }
 
 

src/runtime.cc

@@ -6192,6 +6192,7 @@ template <class Converter>
 MUST_USE_RESULT static MaybeObject* ConvertCaseHelper(
     Isolate* isolate,
     String* s,
+    String::Encoding result_encoding,
     int length,
     int input_string_length,
     unibrow::Mapping<Converter, 128>* mapping) {
@@ -6207,7 +6208,7 @@ MUST_USE_RESULT static MaybeObject* ConvertCaseHelper(
   // might break in the future if we implement more context and locale
   // dependent upper/lower conversions.
   Object* o;
-  { MaybeObject* maybe_o = s->IsOneByteRepresentation()
+  { MaybeObject* maybe_o = result_encoding == String::ONE_BYTE_ENCODING
         ? isolate->heap()->AllocateRawOneByteString(length)
         : isolate->heap()->AllocateRawTwoByteString(length);
     if (!maybe_o->ToObject(&o)) return maybe_o;
@@ -6215,6 +6216,8 @@ MUST_USE_RESULT static MaybeObject* ConvertCaseHelper(
   String* result = String::cast(o);
   bool has_changed_character = false;
 
+  DisallowHeapAllocation no_gc;
+
   // Convert all characters to upper case, assuming that they will fit
   // in the buffer
   Access<ConsStringIteratorOp> op(
@@ -6223,6 +6226,10 @@ MUST_USE_RESULT static MaybeObject* ConvertCaseHelper(
   unibrow::uchar chars[Converter::kMaxWidth];
   // We can assume that the string is not empty
   uc32 current = stream.GetNext();
+  // y with umlauts is the only character that stops fitting into one-byte
+  // when converting to uppercase.
+  static const uc32 yuml_code = 0xff;
+  bool ignore_yuml = result->IsSeqTwoByteString() || Converter::kIsToLower;
   for (int i = 0; i < length;) {
     bool has_next = stream.HasMore();
     uc32 next = has_next ? stream.GetNext() : 0;
@@ -6231,13 +6238,14 @@ MUST_USE_RESULT static MaybeObject* ConvertCaseHelper(
       // The case conversion of this character is the character itself.
       result->Set(i, current);
       i++;
-    } else if (char_length == 1) {
+    } else if (char_length == 1 && (ignore_yuml || current != yuml_code)) {
       // Common case: converting the letter resulted in one character.
       ASSERT(static_cast<uc32>(chars[0]) != current);
       result->Set(i, chars[0]);
       has_changed_character = true;
       i++;
     } else if (length == input_string_length) {
+      bool found_yuml = (current == yuml_code);
       // We've assumed that the result would be as long as the
       // input but here is a character that converts to several
       // characters.  No matter, we calculate the exact length
@@ -6257,6 +6265,7 @@ MUST_USE_RESULT static MaybeObject* ConvertCaseHelper(
       int current_length = i + char_length + next_length;
       while (stream.HasMore()) {
         current = stream.GetNext();
+        found_yuml |= (current == yuml_code);
         // NOTE: we use 0 as the next character here because, while
         // the next character may affect what a character converts to,
         // it does not in any case affect the length of what it convert
@@ -6269,8 +6278,10 @@ MUST_USE_RESULT static MaybeObject* ConvertCaseHelper(
           return Failure::OutOfMemoryException(0x13);
         }
       }
-      // Try again with the real length.
-      return Smi::FromInt(current_length);
+      // Try again with the real length.  Return signed if we need
+      // to allocate a two-byte string for y-umlaut to uppercase.
+      return (found_yuml && !ignore_yuml) ? Smi::FromInt(-current_length)
+                                          : Smi::FromInt(current_length);
     } else {
       for (int j = 0; j < char_length; j++) {
         result->Set(i, chars[j]);
@@ -6316,25 +6327,22 @@ static inline uintptr_t AsciiRangeMask(uintptr_t w, char m, char n) {
 }
 
 
-enum AsciiCaseConversion {
-  ASCII_TO_LOWER,
-  ASCII_TO_UPPER
-};
-
-
-template <AsciiCaseConversion dir>
-struct FastAsciiConverter {
-  static bool Convert(char* dst, char* src, int length, bool* changed_out) {
+template<class Converter>
+static bool FastAsciiConvert(char* dst,
+                             char* src,
+                             int length,
+                             bool* changed_out) {
 #ifdef DEBUG
     char* saved_dst = dst;
     char* saved_src = src;
 #endif
+  DisallowHeapAllocation no_gc;
   // We rely on the distance between upper and lower case letters
   // being a known power of 2.
   ASSERT('a' - 'A' == (1 << 5));
   // Boundaries for the range of input characters than require conversion.
-    const char lo = (dir == ASCII_TO_LOWER) ? 'A' - 1 : 'a' - 1;
-    const char hi = (dir == ASCII_TO_LOWER) ? 'Z' + 1 : 'z' + 1;
+  static const char lo = Converter::kIsToLower ? 'A' - 1 : 'a' - 1;
+  static const char hi = Converter::kIsToLower ? 'Z' + 1 : 'z' + 1;
   bool changed = false;
   uintptr_t or_acc = 0;
   char* const limit = src + length;
@@ -6382,55 +6390,44 @@ struct FastAsciiConverter {
   if ((or_acc & kAsciiMask) != 0) {
     return false;
   }
-#ifdef DEBUG
-    CheckConvert(saved_dst, saved_src, length, changed);
-#endif
+
+  ASSERT(CheckFastAsciiConvert(
+             saved_dst, saved_src, length, changed, Converter::kIsToLower));
+
   *changed_out = changed;
   return true;
-  }
+}
 
 #ifdef DEBUG
-  static void CheckConvert(char* dst, char* src, int length, bool changed) {
+static bool CheckFastAsciiConvert(char* dst,
+                                  char* src,
+                                  int length,
+                                  bool changed,
+                                  bool is_to_lower) {
   bool expected_changed = false;
   for (int i = 0; i < length; i++) {
     if (dst[i] == src[i]) continue;
     expected_changed = true;
-      if (dir == ASCII_TO_LOWER) {
+    if (is_to_lower) {
       ASSERT('A' <= src[i] && src[i] <= 'Z');
       ASSERT(dst[i] == src[i] + ('a' - 'A'));
     } else {
-        ASSERT(dir == ASCII_TO_UPPER);
       ASSERT('a' <= src[i] && src[i] <= 'z');
       ASSERT(dst[i] == src[i] - ('a' - 'A'));
     }
   }
-    ASSERT(expected_changed == changed);
-  }
+  return (expected_changed == changed);
+}
 #endif
-};
-
-
-struct ToLowerTraits {
-  typedef unibrow::ToLowercase UnibrowConverter;
-
-  typedef FastAsciiConverter<ASCII_TO_LOWER> AsciiConverter;
-};
-
-
-struct ToUpperTraits {
-  typedef unibrow::ToUppercase UnibrowConverter;
-
-  typedef FastAsciiConverter<ASCII_TO_UPPER> AsciiConverter;
-};
 
 }  // namespace
 
 
-template <typename ConvertTraits>
+template <class Converter>
 MUST_USE_RESULT static MaybeObject* ConvertCase(
     Arguments args,
     Isolate* isolate,
-    unibrow::Mapping<typename ConvertTraits::UnibrowConverter, 128>* mapping) {
+    unibrow::Mapping<Converter, 128>* mapping) {
   SealHandleScope shs(isolate);
   CONVERT_ARG_CHECKED(String, s, 0);
   s = s->TryFlattenGetString();
@@ -6452,7 +6449,7 @@ MUST_USE_RESULT static MaybeObject* ConvertCase(
     }
     SeqOneByteString* result = SeqOneByteString::cast(o);
     bool has_changed_character;
-    bool is_ascii = ConvertTraits::AsciiConverter::Convert(
+    bool is_ascii = FastAsciiConvert<Converter>(
         reinterpret_cast<char*>(result->GetChars()),
         reinterpret_cast<char*>(SeqOneByteString::cast(s)->GetChars()),
         length,
@@ -6463,31 +6460,35 @@ MUST_USE_RESULT static MaybeObject* ConvertCase(
     }
   }
 
+  String::Encoding result_encoding = s->IsOneByteRepresentationUnderneath()
+      ? String::ONE_BYTE_ENCODING : String::TWO_BYTE_ENCODING;
   Object* answer;
-  { MaybeObject* maybe_answer =
-        ConvertCaseHelper(isolate, s, length, length, mapping);
+  { MaybeObject* maybe_answer = ConvertCaseHelper(
+        isolate, s, result_encoding, length, length, mapping);
     if (!maybe_answer->ToObject(&answer)) return maybe_answer;
   }
   if (answer->IsSmi()) {
-    // Retry with correct length.
-    { MaybeObject* maybe_answer =
-          ConvertCaseHelper(isolate,
-                            s, Smi::cast(answer)->value(), length, mapping);
-      if (!maybe_answer->ToObject(&answer)) return maybe_answer;
+    int new_length = Smi::cast(answer)->value();
+    if (new_length < 0) {
+      result_encoding = String::TWO_BYTE_ENCODING;
+      new_length = -new_length;
     }
+    MaybeObject* maybe_answer = ConvertCaseHelper(
+        isolate, s, result_encoding, new_length, length, mapping);
+    if (!maybe_answer->ToObject(&answer)) return maybe_answer;
   }
   return answer;
 }
 
 
 RUNTIME_FUNCTION(MaybeObject*, Runtime_StringToLowerCase) {
-  return ConvertCase<ToLowerTraits>(
+  return ConvertCase(
       args, isolate, isolate->runtime_state()->to_lower_mapping());
 }
 
 
 RUNTIME_FUNCTION(MaybeObject*, Runtime_StringToUpperCase) {
-  return ConvertCase<ToUpperTraits>(
+  return ConvertCase(
       args, isolate, isolate->runtime_state()->to_upper_mapping());
 }
 

src/unicode.h

@@ -235,6 +235,7 @@ struct ConnectorPunctuation {
 };
 struct ToLowercase {
   static const int kMaxWidth = 3;
+  static const bool kIsToLower = true;
   static int Convert(uchar c,
                      uchar n,
                      uchar* result,
@@ -242,6 +243,7 @@ struct ToLowercase {
 };
 struct ToUppercase {
   static const int kMaxWidth = 3;
+  static const bool kIsToLower = false;
   static int Convert(uchar c,
                      uchar n,
                      uchar* result,

test/mjsunit/regress/regress-2984.js

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+assertEquals("\u0178", "\xff".toUpperCase());
+assertEquals("abcdefghijklmn\xffopq",
+             ("ABCDEFGHIJKL" + "MN\u0178OPQ").toLowerCase());
+assertEquals("\xff", "\u0178".toLowerCase());
+assertEquals("ABCDEFGHIJKLMN\u0178OPQ",
+             ("abcdefghijk" + "lmn\xffopq").toUpperCase());
+