Strtod fast-case that uses DiyFps and cached powers of ten.

src/fast-dtoa.cc

 // Copyright 2010 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 595 matching lines @@
   // Grisu3 will never output representations that lie exactly on a boundary.
   DiyFp boundary_minus, boundary_plus;
   Double(v).NormalizedBoundaries(&boundary_minus, &boundary_plus);
   ASSERT(boundary_plus.e() == w.e());
   DiyFp ten_mk;  // Cached power of ten: 10^-k
   int mk;        // -k
   int ten_mk_minimal_binary_exponent =
      kMinimalTargetExponent - (w.e() + DiyFp::kSignificandSize);
   int ten_mk_maximal_binary_exponent =
      kMaximalTargetExponent - (w.e() + DiyFp::kSignificandSize);
-  GetCachedPowerForBinaryExponentRange(ten_mk_minimal_binary_exponent,
-                                       ten_mk_maximal_binary_exponent,
-                                       &ten_mk, &mk);
+  PowersOfTenCache::GetCachedPowerForBinaryExponentRange(
+      ten_mk_minimal_binary_exponent,
+      ten_mk_maximal_binary_exponent,
+      &ten_mk, &mk);
   ASSERT((kMinimalTargetExponent <= w.e() + ten_mk.e() +
           DiyFp::kSignificandSize) &&
          (kMaximalTargetExponent >= w.e() + ten_mk.e() +
           DiyFp::kSignificandSize));
   // Note that ten_mk is only an approximation of 10^-k. A DiyFp only contains a
   // 64 bit significand and ten_mk is thus only precise up to 64 bits.
 
   // The DiyFp::Times procedure rounds its result, and ten_mk is approximated
   // too. The variable scaled_w (as well as scaled_boundary_minus/plus) are now
   // off by a small amount.
@@ skipping 35 matching lines @@
                           Vector<char> buffer,
                           int* length,
                           int* decimal_exponent) {
   DiyFp w = Double(v).AsNormalizedDiyFp();
   DiyFp ten_mk;  // Cached power of ten: 10^-k
   int mk;        // -k
   int ten_mk_minimal_binary_exponent =
      kMinimalTargetExponent - (w.e() + DiyFp::kSignificandSize);
   int ten_mk_maximal_binary_exponent =
      kMaximalTargetExponent - (w.e() + DiyFp::kSignificandSize);
-  GetCachedPowerForBinaryExponentRange(ten_mk_minimal_binary_exponent,
-                                       ten_mk_maximal_binary_exponent,
-                                       &ten_mk, &mk);
+  PowersOfTenCache::GetCachedPowerForBinaryExponentRange(
+      ten_mk_minimal_binary_exponent,
+      ten_mk_maximal_binary_exponent,
+      &ten_mk, &mk);
   ASSERT((kMinimalTargetExponent <= w.e() + ten_mk.e() +
           DiyFp::kSignificandSize) &&
          (kMaximalTargetExponent >= w.e() + ten_mk.e() +
           DiyFp::kSignificandSize));
   // Note that ten_mk is only an approximation of 10^-k. A DiyFp only contains a
   // 64 bit significand and ten_mk is thus only precise up to 64 bits.
 
   // The DiyFp::Times procedure rounds its result, and ten_mk is approximated
   // too. The variable scaled_w (as well as scaled_boundary_minus/plus) are now
   // off by a small amount.
@@ skipping 38 matching lines @@
       UNREACHABLE();
   }
   if (result) {
     *decimal_point = *length + decimal_exponent;
     buffer[*length] = '\0';
   }
   return result;
 }
 
 } }  // namespace v8::internal