Reland of "Avoid number range holes in bitset types."

src/types.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <iomanip>
 
 #include "src/types.h"
 
 #include "src/ostreams.h"
 #include "src/types-inl.h"
@@ skipping 261 matching lines @@
 }
 
 
 template<class Config>
 typename TypeImpl<Config>::bitset
 TypeImpl<Config>::BitsetType::Lub(double value) {
   DisallowHeapAllocation no_allocation;
   if (i::IsMinusZero(value)) return kMinusZero;
   if (std::isnan(value)) return kNaN;
   if (IsUint32Double(value) || IsInt32Double(value)) return Lub(value, value);
-  return kOtherNumber;
+  return kPlainNumber;
 }
 
 
 // Minimum values of regular numeric bitsets when SmiValuesAre31Bits.
-template<class Config>
+template <class Config>
 const typename TypeImpl<Config>::BitsetType::BitsetMin
-TypeImpl<Config>::BitsetType::BitsetMins31[] = {
-    {kOtherNumber, -V8_INFINITY},
-    {kOtherSigned32, kMinInt},
-    {kOtherSignedSmall, -0x40000000},
-    {kUnsignedSmall, 0},
-    {kOtherUnsigned31, 0x40000000},
-    {kOtherUnsigned32, 0x80000000},
-    {kOtherNumber, static_cast<double>(kMaxUInt32) + 1}
-};
+    TypeImpl<Config>::BitsetType::BitsetMins31[] = {
+        {kOtherNumber, -V8_INFINITY},
+        {kOtherSigned32, kMinInt},
+        {kNegativeSignedSmall, -0x40000000},
+        {kUnsignedSmall, 0},
+        {kOtherUnsigned31, 0x40000000},
+        {kOtherUnsigned32, 0x80000000},
+        {kOtherNumber, static_cast<double>(kMaxUInt32) + 1}};
 
 
 // Minimum values of regular numeric bitsets when SmiValuesAre32Bits.
 // OtherSigned32 and OtherUnsigned31 are empty (see the diagrams in types.h).
-template<class Config>
+template <class Config>
 const typename TypeImpl<Config>::BitsetType::BitsetMin
-TypeImpl<Config>::BitsetType::BitsetMins32[] = {
-    {kOtherNumber, -V8_INFINITY},
-    {kOtherSignedSmall, kMinInt},
-    {kUnsignedSmall, 0},
-    {kOtherUnsigned32, 0x80000000},
-    {kOtherNumber, static_cast<double>(kMaxUInt32) + 1}
-};
+    TypeImpl<Config>::BitsetType::BitsetMins32[] = {
+        {kOtherNumber, -V8_INFINITY},
+        {kNegativeSignedSmall, kMinInt},
+        {kUnsignedSmall, 0},
+        {kOtherUnsigned32, 0x80000000},
+        {kOtherNumber, static_cast<double>(kMaxUInt32) + 1}};
 
 
 template<class Config>
 typename TypeImpl<Config>::bitset
 TypeImpl<Config>::BitsetType::Lub(double min, double max) {
   DisallowHeapAllocation no_allocation;
   int lub = kNone;
   const BitsetMin* mins = BitsetMins();
 
+  // Make sure the min-max range touches 0, so we are guaranteed no holes
+  // in unions of valid bitsets.
+  if (max < -1) max = -1;
+  if (min > 0) min = 0;
+
   for (size_t i = 1; i < BitsetMinsSize(); ++i) {
     if (min < mins[i].min) {
       lub |= mins[i-1].bits;
       if (max < mins[i].min) return lub;
     }
   }
   return lub |= mins[BitsetMinsSize()-1].bits;
 }
 
 
@@ skipping 650 matching lines @@
     os << name;
     return;
   }
 
   static const bitset named_bitsets[] = {
 #define BITSET_CONSTANT(type, value) REPRESENTATION(k##type),
       REPRESENTATION_BITSET_TYPE_LIST(BITSET_CONSTANT)
 #undef BITSET_CONSTANT
 
 #define BITSET_CONSTANT(type, value) SEMANTIC(k##type),
+      INTERNAL_BITSET_TYPE_LIST(BITSET_CONSTANT)
       SEMANTIC_BITSET_TYPE_LIST(BITSET_CONSTANT)
 #undef BITSET_CONSTANT
   };
 
   bool is_first = true;
   os << "(";
   for (int i(arraysize(named_bitsets) - 1); bits != 0 && i >= 0; --i) {
     bitset subset = named_bitsets[i];
     if ((bits & subset) == subset) {
       if (!is_first) os << " | ";
@@ skipping 93 matching lines @@
 template class TypeImpl<HeapTypeConfig>::Iterator<i::Object>;
 
 template TypeImpl<ZoneTypeConfig>::TypeHandle
   TypeImpl<ZoneTypeConfig>::Convert<HeapType>(
     TypeImpl<HeapTypeConfig>::TypeHandle, TypeImpl<ZoneTypeConfig>::Region*);
 template TypeImpl<HeapTypeConfig>::TypeHandle
   TypeImpl<HeapTypeConfig>::Convert<Type>(
     TypeImpl<ZoneTypeConfig>::TypeHandle, TypeImpl<HeapTypeConfig>::Region*);
 
 } }  // namespace v8::internal