diff -urNp a/Source/JavaScriptCore/heap/MarkedBlock.h b/Source/JavaScriptCore/heap/MarkedBlock.h
--- a/Source/JavaScriptCore/heap/MarkedBlock.h	2018-07-25 19:56:28.000000000 +0800
+++ b/Source/JavaScriptCore/heap/MarkedBlock.h	2020-02-24 14:29:28.738218959 +0800
@@ -68,7 +68,7 @@ public:
     static constexpr size_t atomSize = 16; // bytes
 
     // Block size must be at least as large as the system page size.
-#if CPU(PPC64) || CPU(PPC64LE) || CPU(PPC) || CPU(UNKNOWN)
+#if CPU(PPC64) || CPU(PPC64LE) || CPU(PPC) || CPU(ARM64) || CPU(UNKNOWN)
     static constexpr size_t blockSize = 64 * KB;
 #else
     static constexpr size_t blockSize = 16 * KB;
