Fix alignment of Code::kConstantPoolOffset.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 66b9b8d21bbf19e01a4800964f4ea76543639f96..ab3e4a343e99616cd81b1de0fe48d7cfc431c9eb 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -5370,7 +5370,7 @@ class Code: public HeapObject {
       kKindSpecificFlags1Offset + kIntSize;
   // Note: We might be able to squeeze this into the flags above.
   static const int kPrologueOffset = kKindSpecificFlags2Offset + kIntSize;
-  static const int kConstantPoolOffset = kPrologueOffset + kPointerSize;
+  static const int kConstantPoolOffset = kPrologueOffset + kIntSize;
 
   static const int kHeaderPaddingStart = kConstantPoolOffset + kPointerSize;
 
@@ -5378,6 +5378,8 @@ class Code: public HeapObject {
   // the Code object header.
   static const int kHeaderSize =
       (kHeaderPaddingStart + kCodeAlignmentMask) & ~kCodeAlignmentMask;
+  // Ensure that the slot for the constant pool pointer is aligned.
+  STATIC_ASSERT((kConstantPoolOffset & kPointerAlignmentMask) == 0);
 
   // Byte offsets within kKindSpecificFlags1Offset.
   static const int kOptimizableOffset = kKindSpecificFlags1Offset;