4 files changed, 13 insertions, 20 deletions
diff --git a/Source/JavaScriptCore/runtime/Butterfly.h b/Source/JavaScriptCore/runtime/Butterfly.h
index 4b8d53f7e..bbbda9461 100644
--- a/Source/JavaScriptCore/runtime/Butterfly.h
+++ b/Source/JavaScriptCore/runtime/Butterfly.h
@@ -110,7 +110,9 @@ public:
 
     void* base(size_t preCapacity, size_t propertyCapacity) { return propertyStorage() - propertyCapacity - preCapacity; }
     void* base(Structure*);
-    
+
+    static Butterfly* createOrGrowArrayRight(Butterfly*, JSGlobalData&, Structure* oldStructure, size_t propertyCapacity, bool hadIndexingHeader, size_t oldIndexingPayloadSizeInBytes, size_t newIndexingPayloadSizeInBytes); 
+
     // The butterfly reallocation methods perform the reallocation itself but do not change any
     // of the meta-data to reflect that the reallocation occurred. Note that this set of
     // methods is not exhaustive and is not intended to encapsulate all possible allocation
diff --git a/Source/JavaScriptCore/runtime/ButterflyInlines.h b/Source/JavaScriptCore/runtime/ButterflyInlines.h
index 9167497a4..f01458950 100644
--- a/Source/JavaScriptCore/runtime/ButterflyInlines.h
+++ b/Source/JavaScriptCore/runtime/ButterflyInlines.h
@@ -99,6 +99,13 @@ inline Butterfly* Butterfly::growPropertyStorage(JSGlobalData& globalData, Struc
         globalData, oldStructure, oldStructure->outOfLineCapacity(), newPropertyCapacity);
 }
 
+inline Butterfly* Butterfly::createOrGrowArrayRight(Butterfly* oldButterfly, JSGlobalData& globalData, Structure* oldStructure, size_t propertyCapacity, bool hadIndexingHeader, size_t oldIndexingPayloadSizeInBytes, size_t newIndexingPayloadSizeInBytes)
+{
+    if (!oldButterfly)
+        return create(globalData, 0, propertyCapacity, true, IndexingHeader(), newIndexingPayloadSizeInBytes);
+    return oldButterfly->growArrayRight(globalData, oldStructure, propertyCapacity, hadIndexingHeader, oldIndexingPayloadSizeInBytes, newIndexingPayloadSizeInBytes);
+}
+
 inline Butterfly* Butterfly::growArrayRight(JSGlobalData& globalData, Structure* oldStructure, size_t propertyCapacity, bool hadIndexingHeader, size_t oldIndexingPayloadSizeInBytes, size_t newIndexingPayloadSizeInBytes)
 {
     ASSERT_UNUSED(oldStructure, !indexingHeader()->preCapacity(oldStructure));
diff --git a/Source/JavaScriptCore/runtime/JSObject.cpp b/Source/JavaScriptCore/runtime/JSObject.cpp
index dc73e04b0..32adefd2f 100644
--- a/Source/JavaScriptCore/runtime/JSObject.cpp
+++ b/Source/JavaScriptCore/runtime/JSObject.cpp
@@ -110,7 +110,7 @@ ALWAYS_INLINE void JSObject::copyButterfly(CopyVisitor& visitor, Butterfly* butt
         indexingPayloadSizeInBytes = 0;
     }
     size_t capacityInBytes = Butterfly::totalSize(preCapacity, propertyCapacity, hasIndexingHeader, indexingPayloadSizeInBytes);
-    if (visitor.checkIfShouldCopy(butterfly->base(preCapacity, propertyCapacity), capacityInBytes)) {
+    if (visitor.checkIfShouldCopy(butterfly->base(preCapacity, propertyCapacity))) {
         Butterfly* newButterfly = Butterfly::createUninitializedDuringCollection(visitor, preCapacity, propertyCapacity, hasIndexingHeader, indexingPayloadSizeInBytes);
         
         // Copy the properties.
@@ -610,7 +610,7 @@ Butterfly* JSObject::createInitialIndexedStorage(JSGlobalData& globalData, unsig
     ASSERT(!structure()->needsSlowPutIndexing());
     ASSERT(!indexingShouldBeSparse());
     unsigned vectorLength = std::max(length, BASE_VECTOR_LEN);
-    Butterfly* newButterfly = m_butterfly->growArrayRight(
+    Butterfly* newButterfly = Butterfly::createOrGrowArrayRight(m_butterfly, 
         globalData, structure(), structure()->outOfLineCapacity(), false, 0,
         elementSize * vectorLength);
     newButterfly->setPublicLength(length);
@@ -656,7 +656,7 @@ ArrayStorage* JSObject::createArrayStorage(JSGlobalData& globalData, unsigned le
 {
     IndexingType oldType = structure()->indexingType();
     ASSERT_UNUSED(oldType, !hasIndexedProperties(oldType));
-    Butterfly* newButterfly = m_butterfly->growArrayRight(
+    Butterfly* newButterfly = Butterfly::createOrGrowArrayRight(m_butterfly, 
         globalData, structure(), structure()->outOfLineCapacity(), false, 0,
         ArrayStorage::sizeFor(vectorLength));
     if (!newButterfly)
diff --git a/Source/JavaScriptCore/runtime/MathObject.cpp b/Source/JavaScriptCore/runtime/MathObject.cpp
index f939b8dd4..7634487ad 100644
--- a/Source/JavaScriptCore/runtime/MathObject.cpp
+++ b/Source/JavaScriptCore/runtime/MathObject.cpp
@@ -232,22 +232,6 @@ static ALWAYS_INLINE double mathPow(double x, double y)
 
 ALWAYS_INLINE double mathPow(double x, double y)
 {
-#if COMPILER(MINGW64)
-    // MinGW-w64 has a custom implementation for pow.
-    // This handles certain special cases that are different.
-    if ((x == 0.0 || isinf(x)) && isfinite(y)) {
-        double f;
-        if (modf(y, &f) != 0.0)
-            return ((x == 0.0) ^ (y > 0.0)) ? std::numeric_limits<double>::infinity() : 0.0;
-    }
-
-    if (x == 2.0) {
-        int yInt = static_cast<int>(y);
-        if (y == yInt)
-            return ldexp(1.0, yInt);
-    }
-#endif
-
     return pow(x, y);
 }