Fix Math.pow(-0, 0.5) and Math.pow(-0, -0.5). These are not equal to sqrt(-0...

src/assembler.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 820 matching lines @@
   return p;
 }
 
 
 double power_double_double(double x, double y) {
   int y_int = static_cast<int>(y);
   if (y == y_int) {
     return power_double_int(x, y_int);  // Returns 1.0 for exponent 0.
   }
   if (!isinf(x)) {
-    if (y == 0.5) return sqrt(x);
-    if (y == -0.5) return 1.0 / sqrt(x);
+    if (y == 0.5) return sqrt(x + 0.0);  // -0 must be converted to +0.
+    if (y == -0.5) return 1.0 / sqrt(x + 0.0);
   }
   if (isnan(y) || ((x == 1 || x == -1) && isinf(y))) {
     return OS::nan_value();
   }
   return pow(x, y);
 }
 
 
 ExternalReference ExternalReference::power_double_double_function() {
   return ExternalReference(Redirect(FUNCTION_ADDR(power_double_double)));
@@ skipping 105 matching lines @@
     assembler_->RecordRelocInfo(RelocInfo::POSITION, state_.current_position);
     state_.written_position = state_.current_position;
     written = true;
   }
 
   // Return whether something was written.
   return written;
 }
 
 } }  // namespace v8::internal