On 64bit targets, increase the size of data a BVSparseNode can hold from

32-bit to 64-bit.

Author: Meghana Gupta

lib/Common/DataStructures/SparseBitVector.h

@@ -4,11 +4,7 @@
 //-------------------------------------------------------------------------------------------------------
 #pragma once
 
-#if defined(_M_ARM64) || defined(_M_X64)
-typedef  BVUnit32 SparseBVUnit;
-#else
 typedef  BVUnit64 SparseBVUnit;
-#endif
 
 #define FOREACH_BITSET_IN_SPARSEBV(index, bv) \
 { \
@@ -64,15 +60,8 @@ typedef  BVUnit64 SparseBVUnit;
 struct BVSparseNode
 {
     BVIndex         startIndex;
-#if defined(_M_ARM64) || defined(_M_X64)
-    //64-bit: the order is changed to make sure it fits in 16 bytes
-    SparseBVUnit    data;
-    BVSparseNode *  next;
-#else //_M_IX86 and _M_ARM32
     BVSparseNode *  next;
     SparseBVUnit    data;
-#endif
-
 
     BVSparseNode(BVIndex beginIndex, BVSparseNode * nextNode);
 
@@ -91,7 +80,11 @@ struct BVSparseNode
 #endif
 };
 
-CompileAssert(sizeof(BVSparseNode) == 16); // Performance assert, BVSparseNode is heavily used in the backend, do perf measurement before changing this.
+#if defined(_M_X64)
+CompileAssert(sizeof(BVSparseNode) == 24); // Performance assert, BVSparseNode is heavily used in the backend, do perf measurement before changing this.
+#else
+CompileAssert(sizeof(BVSparseNode) == 16);
+#endif
 
 template <class TAllocator>
 class BVSparse

lib/Common/Memory/ArenaAllocator.cpp

@@ -166,7 +166,6 @@ ArenaAllocatorBase<TFreeListPolicy, ObjectAlignmentBitShiftArg, RequireObjectAli
 RealAllocInlined(size_t nbytes)
 {
     Assert(nbytes != 0);
-    Assert((nbytes & (ObjectAlignment - 1)) == 0);
 
 #ifdef ARENA_MEMORY_VERIFY
     if (Js::Configuration::Global.flags.ArenaUseHeapAlloc)

lib/Common/Memory/ArenaAllocator.h

@@ -458,7 +458,6 @@ class JitArenaAllocator : public ArenaAllocator
         // Fast path
         if (sizeof(BVSparseNode) == requestedBytes)
         {
-            AssertMsg(Math::Align(requestedBytes, ArenaAllocatorBase::ObjectAlignment) == requestedBytes, "Assert for Perf, T should always be aligned");
             // Fast path for BVSparseNode allocation
             if (bvFreeList)
             {