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

src/cached-powers.cc

Index: src/cached-powers.cc
diff --git a/src/cached-powers.cc b/src/cached-powers.cc
index 43dbc7855e42b50e4800580d6cf9b6386c1d291b..8f822862bd710d079da301cbb11a5c24d70a5cbc 100644
--- a/src/cached-powers.cc
+++ b/src/cached-powers.cc
@@ -42,11 +42,6 @@ struct CachedPower {
 };
 
 static const CachedPower kCachedPowers[] = {
-  {V8_2PART_UINT64_C(0xfa8fd5a0, 081c0288), -1220, -348},
-  {V8_2PART_UINT64_C(0xbaaee17f, a23ebf76), -1193, -340},
-  {V8_2PART_UINT64_C(0x8b16fb20, 3055ac76), -1166, -332},
-  {V8_2PART_UINT64_C(0xcf42894a, 5dce35ea), -1140, -324},
-  {V8_2PART_UINT64_C(0x9a6bb0aa, 55653b2d), -1113, -316},
   {V8_2PART_UINT64_C(0xe61acf03, 3d1a45df), -1087, -308},
   {V8_2PART_UINT64_C(0xab70fe17, c79ac6ca), -1060, -300},
   {V8_2PART_UINT64_C(0xff77b1fc, bebcdc4f), -1034, -292},
@@ -134,44 +129,24 @@ static const CachedPower kCachedPowers[] = {
 static const int kCachedPowersLength = ARRAY_SIZE(kCachedPowers);
 static const int kCachedPowersOffset = -kCachedPowers[0].decimal_exponent;
 static const double kD_1_LOG2_10 = 0.30102999566398114;  //  1 / lg(10)
-const int PowersOfTenCache::kDecimalExponentDistance =
+static const int kCachedPowersDecimalDistance =
     kCachedPowers[1].decimal_exponent - kCachedPowers[0].decimal_exponent;
-const int PowersOfTenCache::kMinDecimalExponent =
-    kCachedPowers[0].decimal_exponent;
-const int PowersOfTenCache::kMaxDecimalExponent =
-    kCachedPowers[kCachedPowersLength - 1].decimal_exponent;
 
-void PowersOfTenCache::GetCachedPowerForBinaryExponentRange(
-    int min_exponent,
-    int max_exponent,
-    DiyFp* power,
-    int* decimal_exponent) {
-  int kQ = DiyFp::kSignificandSize;
-  double k = ceiling((min_exponent + kQ - 1) * kD_1_LOG2_10);
-  int foo = kCachedPowersOffset;
-  int index =
-      (foo + static_cast<int>(k) - 1) / kDecimalExponentDistance + 1;
-  ASSERT(0 <= index && index < kCachedPowersLength);
-  CachedPower cached_power = kCachedPowers[index];
-  ASSERT(min_exponent <= cached_power.binary_exponent);
-  ASSERT(cached_power.binary_exponent <= max_exponent);
-  *decimal_exponent = cached_power.decimal_exponent;
-  *power = DiyFp(cached_power.significand, cached_power.binary_exponent);
-}
-
-
-void PowersOfTenCache::GetCachedPowerForDecimalExponent(int requested_exponent,
-                                                        DiyFp* power,
-                                                        int* found_exponent) {
-  ASSERT(kMinDecimalExponent <= requested_exponent);
-  ASSERT(requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance);
-  int index =
-      (requested_exponent + kCachedPowersOffset) / kDecimalExponentDistance;
-  CachedPower cached_power = kCachedPowers[index];
-  *power = DiyFp(cached_power.significand, cached_power.binary_exponent);
-  *found_exponent = cached_power.decimal_exponent;
-  ASSERT(*found_exponent <= requested_exponent);
-  ASSERT(requested_exponent < *found_exponent + kDecimalExponentDistance);
+void GetCachedPowerForBinaryExponentRange(int min_exponent,
+                                          int max_exponent,
+                                          DiyFp* power,
+                                          int* decimal_exponent) {
+    int kQ = DiyFp::kSignificandSize;
+    double k = ceiling((min_exponent + kQ - 1) * kD_1_LOG2_10);
+    int foo = kCachedPowersOffset;
+    int index =
+        (foo + static_cast<int>(k) - 1) / kCachedPowersDecimalDistance + 1;
+    ASSERT(0 <= index && index < kCachedPowersLength);
+    CachedPower cached_power = kCachedPowers[index];
+    ASSERT(min_exponent <= cached_power.binary_exponent);
+    ASSERT(cached_power.binary_exponent <= max_exponent);
+    *decimal_exponent = cached_power.decimal_exponent;
+    *power = DiyFp(cached_power.significand, cached_power.binary_exponent);
 }
 
 } }  // namespace v8::internal