Add bignum fall-back when the fast dtoa doesn't succeed. This removes Gay's d...

src/conversions.cc

 // Copyright 2006-2008 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
@@ skipping 636 matching lines @@
 
   if (nonzero_digit_dropped) {
     buffer[buffer_pos++] = '1';
     exponent--;
   }
 
   ASSERT(buffer_pos < kBufferSize);
   buffer[buffer_pos] = '\0';
 
   double converted = Strtod(Vector<const char>(buffer, buffer_pos), exponent);
-  return sign? -converted: converted;
+  return sign ? -converted : converted;
 }
 
 
 double StringToDouble(String* str, int flags, double empty_string_val) {
   StringShape shape(str);
   if (shape.IsSequentialAscii()) {
     const char* begin = SeqAsciiString::cast(str)->GetChars();
     const char* end = begin + str->length();
     return InternalStringToDouble(begin, end, flags, empty_string_val);
   } else if (shape.IsSequentialTwoByte()) {
@@ skipping 36 matching lines @@
 
 
 double StringToDouble(Vector<const char> str,
                       int flags,
                       double empty_string_val) {
   const char* end = str.start() + str.length();
   return InternalStringToDouble(str.start(), end, flags, empty_string_val);
 }
 
 
-extern "C" char* dtoa(double d, int mode, int ndigits,
-                      int* decpt, int* sign, char** rve);
-
-extern "C" void freedtoa(char* s);
-
 const char* DoubleToCString(double v, Vector<char> buffer) {
   StringBuilder builder(buffer.start(), buffer.length());
 
   switch (fpclassify(v)) {
     case FP_NAN:
       builder.AddString("NaN");
       break;
 
     case FP_INFINITE:
       if (v < 0.0) {
         builder.AddString("-Infinity");
       } else {
         builder.AddString("Infinity");
       }
       break;
 
     case FP_ZERO:
       builder.AddCharacter('0');
       break;
 
     default: {
       int decimal_point;
       int sign;
-      char* decimal_rep;
-      bool used_gay_dtoa = false;
       const int kV8DtoaBufferCapacity = kBase10MaximalLength + 1;
-      char v8_dtoa_buffer[kV8DtoaBufferCapacity];
+      char decimal_rep[kV8DtoaBufferCapacity];
       int length;
 
-      if (DoubleToAscii(v, DTOA_SHORTEST, 0,
-                        Vector<char>(v8_dtoa_buffer, kV8DtoaBufferCapacity),
-                        &sign, &length, &decimal_point)) {
-        decimal_rep = v8_dtoa_buffer;
-      } else {
-        decimal_rep = dtoa(v, 0, 0, &decimal_point, &sign, NULL);
-        used_gay_dtoa = true;
-        length = StrLength(decimal_rep);
-      }
+      DoubleToAscii(v, DTOA_SHORTEST, 0,
+                    Vector<char>(decimal_rep, kV8DtoaBufferCapacity),
+                    &sign, &length, &decimal_point);
 
       if (sign) builder.AddCharacter('-');
 
       if (length <= decimal_point && decimal_point <= 21) {
         // ECMA-262 section 9.8.1 step 6.
         builder.AddString(decimal_rep);
         builder.AddPadding('0', decimal_point - length);
 
       } else if (0 < decimal_point && decimal_point <= 21) {
         // ECMA-262 section 9.8.1 step 7.
@@ skipping 13 matching lines @@
         if (length != 1) {
           builder.AddCharacter('.');
           builder.AddString(decimal_rep + 1);
         }
         builder.AddCharacter('e');
         builder.AddCharacter((decimal_point >= 0) ? '+' : '-');
         int exponent = decimal_point - 1;
         if (exponent < 0) exponent = -exponent;
         builder.AddFormatted("%d", exponent);
       }
-
-      if (used_gay_dtoa) freedtoa(decimal_rep);
     }
   }
   return builder.Finalize();
 }
 
 
 const char* IntToCString(int n, Vector<char> buffer) {
   bool negative = false;
   if (n < 0) {
     // We must not negate the most negative int.
@@ skipping 36 matching lines @@
   }
 
   // Find a sufficiently precise decimal representation of n.
   int decimal_point;
   int sign;
   // Add space for the '\0' byte.
   const int kDecimalRepCapacity =
       kMaxDigitsBeforePoint + kMaxDigitsAfterPoint + 1;
   char decimal_rep[kDecimalRepCapacity];
   int decimal_rep_length;
-  bool status = DoubleToAscii(value, DTOA_FIXED, f,
-                              Vector<char>(decimal_rep, kDecimalRepCapacity),
-                              &sign, &decimal_rep_length, &decimal_point);
-  USE(status);
-  ASSERT(status);
+  DoubleToAscii(value, DTOA_FIXED, f,
+                Vector<char>(decimal_rep, kDecimalRepCapacity),
+                &sign, &decimal_rep_length, &decimal_point);
 
   // Create a representation that is padded with zeros if needed.
   int zero_prefix_length = 0;
   int zero_postfix_length = 0;
 
   if (decimal_point <= 0) {
     zero_prefix_length = -decimal_point + 1;
     decimal_point = 1;
   }
 
@@ skipping 65 matching lines @@
 
   bool negative = false;
   if (value < 0) {
     value = -value;
     negative = true;
   }
 
   // Find a sufficiently precise decimal representation of n.
   int decimal_point;
   int sign;
-  char* decimal_rep = NULL;
-  bool used_gay_dtoa = false;
   // f corresponds to the digits after the point. There is always one digit
   // before the point. The number of requested_digits equals hence f + 1.
   // And we have to add one character for the null-terminator.
   const int kV8DtoaBufferCapacity = kMaxDigitsAfterPoint + 1 + 1;
   // Make sure that the buffer is big enough, even if we fall back to the
   // shortest representation (which happens when f equals -1).
   ASSERT(kBase10MaximalLength <= kMaxDigitsAfterPoint + 1);
-  char v8_dtoa_buffer[kV8DtoaBufferCapacity];
+  char decimal_rep[kV8DtoaBufferCapacity];
   int decimal_rep_length;
 
   if (f == -1) {
-    if (DoubleToAscii(value, DTOA_SHORTEST, 0,
-                      Vector<char>(v8_dtoa_buffer, kV8DtoaBufferCapacity),
-                      &sign, &decimal_rep_length, &decimal_point)) {
-      f = decimal_rep_length - 1;
-      decimal_rep = v8_dtoa_buffer;
-    } else {
-      decimal_rep = dtoa(value, 0, 0, &decimal_point, &sign, NULL);
-      decimal_rep_length = StrLength(decimal_rep);
-      f = decimal_rep_length - 1;
-      used_gay_dtoa = true;
-    }
+    DoubleToAscii(value, DTOA_SHORTEST, 0,
+                  Vector<char>(decimal_rep, kV8DtoaBufferCapacity),
+                  &sign, &decimal_rep_length, &decimal_point);
+    f = decimal_rep_length - 1;
   } else {
-    if (DoubleToAscii(value, DTOA_PRECISION, f + 1,
-                      Vector<char>(v8_dtoa_buffer, kV8DtoaBufferCapacity),
-                      &sign, &decimal_rep_length, &decimal_point)) {
-      decimal_rep = v8_dtoa_buffer;
-    } else {
-      decimal_rep = dtoa(value, 2, f + 1, &decimal_point, &sign, NULL);
-      decimal_rep_length = StrLength(decimal_rep);
-      used_gay_dtoa = true;
-    }
+    DoubleToAscii(value, DTOA_PRECISION, f + 1,
+                  Vector<char>(decimal_rep, kV8DtoaBufferCapacity),
+                  &sign, &decimal_rep_length, &decimal_point);
   }
   ASSERT(decimal_rep_length > 0);
   ASSERT(decimal_rep_length <= f + 1);
 
   int exponent = decimal_point - 1;
   char* result =
       CreateExponentialRepresentation(decimal_rep, exponent, negative, f+1);
 
-  if (used_gay_dtoa) {
-    freedtoa(decimal_rep);
-  }
-
   return result;
 }
 
 
 char* DoubleToPrecisionCString(double value, int p) {
   const int kMinimalDigits = 1;
   const int kMaximalDigits = 21;
   ASSERT(p >= kMinimalDigits && p <= kMaximalDigits);
   USE(kMinimalDigits);
 
   bool negative = false;
   if (value < 0) {
     value = -value;
     negative = true;
   }
 
   // Find a sufficiently precise decimal representation of n.
   int decimal_point;
   int sign;
-  char* decimal_rep = NULL;
-  bool used_gay_dtoa = false;
   // Add one for the terminating null character.
   const int kV8DtoaBufferCapacity = kMaximalDigits + 1;
-  char v8_dtoa_buffer[kV8DtoaBufferCapacity];
+  char decimal_rep[kV8DtoaBufferCapacity];
   int decimal_rep_length;
 
-  if (DoubleToAscii(value, DTOA_PRECISION, p,
-                    Vector<char>(v8_dtoa_buffer, kV8DtoaBufferCapacity),
-                    &sign, &decimal_rep_length, &decimal_point)) {
-    decimal_rep = v8_dtoa_buffer;
-  } else {
-    decimal_rep = dtoa(value, 2, p, &decimal_point, &sign, NULL);
-    decimal_rep_length = StrLength(decimal_rep);
-    used_gay_dtoa = true;
-  }
+  DoubleToAscii(value, DTOA_PRECISION, p,
+                Vector<char>(decimal_rep, kV8DtoaBufferCapacity),
+                &sign, &decimal_rep_length, &decimal_point);
   ASSERT(decimal_rep_length <= p);
 
   int exponent = decimal_point - 1;
 
   char* result = NULL;
 
   if (exponent < -6 || exponent >= p) {
     result =
         CreateExponentialRepresentation(decimal_rep, exponent, negative, p);
   } else {
@@ skipping 23 matching lines @@
           const int len = StrLength(decimal_rep + decimal_point);
           const int n = Min(len, p - (builder.position() - extra));
           builder.AddSubstring(decimal_rep + decimal_point, n);
         }
         builder.AddPadding('0', extra + (p - builder.position()));
       }
     }
     result = builder.Finalize();
   }
 
-  if (used_gay_dtoa) {
-    freedtoa(decimal_rep);
-  }
   return result;
 }
 
 
 char* DoubleToRadixCString(double value, int radix) {
   ASSERT(radix >= 2 && radix <= 36);
 
   // Character array used for conversion.
   static const char chars[] = "0123456789abcdefghijklmnopqrstuvwxyz";
 
@@ skipping 56 matching lines @@
   // Allocate result and fill in the parts.
   StringBuilder builder(result_size + 1);
   builder.AddSubstring(integer_buffer + integer_pos + 1, integer_part_size);
   if (decimal_pos > 0) builder.AddCharacter('.');
   builder.AddSubstring(decimal_buffer, decimal_pos);
   return builder.Finalize();
 }
 
 
 } }  // namespace v8::internal