Use std:: on symbols declared in C++-style C headers.

src/hydrogen-instructions.cc

 // Copyright 2012 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 3880 matching lines @@
           return H_CONSTANT_DOUBLE(d);
         default:
           UNREACHABLE();
           break;
       }
     }
     switch (op) {
       case kMathExp:
         return H_CONSTANT_DOUBLE(fast_exp(d));
       case kMathLog:
-        return H_CONSTANT_DOUBLE(log(d));
+        return H_CONSTANT_DOUBLE(std::log(d));
       case kMathSqrt:
         return H_CONSTANT_DOUBLE(fast_sqrt(d));
       case kMathPowHalf:
         return H_CONSTANT_DOUBLE(power_double_double(d, 0.5));
       case kMathAbs:
         return H_CONSTANT_DOUBLE((d >= 0.0) ? d + 0.0 : -d);
       case kMathRound:
         // -0.5 .. -0.0 round to -0.0.
         if ((d >= -0.5 && Double(d).Sign() < 0)) return H_CONSTANT_DOUBLE(-0.0);
         // Doubles are represented as Significant * 2 ^ Exponent. If the
         // Exponent is not negative, the double value is already an integer.
         if (Double(d).Exponent() >= 0) return H_CONSTANT_DOUBLE(d);
-        return H_CONSTANT_DOUBLE(floor(d + 0.5));
+        return H_CONSTANT_DOUBLE(std::floor(d + 0.5));
       case kMathFloor:
-        return H_CONSTANT_DOUBLE(floor(d));
+        return H_CONSTANT_DOUBLE(std::floor(d));
       default:
         UNREACHABLE();
         break;
     }
   } while (false);
   return new(zone) HUnaryMathOperation(context, value, op);
 }
 
 
 HInstruction* HPower::New(Zone* zone,
@@ skipping 518 matching lines @@
       break;
     case kExternalMemory:
       stream->Add("[external-memory]");
       break;
   }
 
   stream->Add("@%d", offset());
 }
 
 } }  // namespace v8::internal