Avoid unaligned access fault in Int32x4/Float32x4::value() on ARM.

runtime/vm/object.h

Index: runtime/vm/object.h
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index d5062633402b9c66a7b4e20c46a5eb4e109c01be..894b59bdcb4579a654871a345dcd4c7f2cc62a98 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -7961,29 +7961,15 @@ class TypedData : public Instance {
   virtual bool CanonicalizeEquals(const Instance& other) const;
   virtual uword ComputeCanonicalTableHash() const;
 
-#if defined(HOST_ARCH_IA32) || defined(HOST_ARCH_X64)
 #define TYPED_GETTER_SETTER(name, type)                                        \
   type Get##name(intptr_t byte_offset) const {                                 \
     NoSafepointScope no_safepoint;                                             \
-    return *reinterpret_cast<type*>(DataAddr(byte_offset));                    \
-  }                                                                            \
-  void Set##name(intptr_t byte_offset, type value) const {                     \
-    NoSafepointScope no_safepoint;                                             \
-    *reinterpret_cast<type*>(DataAddr(byte_offset)) = value;                   \
-  }
-#else  // defined(HOST_ARCH_IA32) || defined(HOST_ARCH_X64)
-#define TYPED_GETTER_SETTER(name, type)                                        \
-  type Get##name(intptr_t byte_offset) const {                                 \
-    NoSafepointScope no_safepoint;                                             \
-    type result;                                                               \
-    memmove(&result, DataAddr(byte_offset), sizeof(type));                     \
-    return result;                                                             \
+    return ReadUnaligned(reinterpret_cast<type*>(DataAddr(byte_offset)));      \
   }                                                                            \
   void Set##name(intptr_t byte_offset, type value) const {                     \
     NoSafepointScope no_safepoint;                                             \
-    memmove(DataAddr(byte_offset), &value, sizeof(type));                      \
+    StoreUnaligned(reinterpret_cast<type*>(DataAddr(byte_offset)), value);     \
   }
-#endif  // defined(HOST_ARCH_IA32) || defined(HOST_ARCH_X64)
 
   TYPED_GETTER_SETTER(Int8, int8_t)
   TYPED_GETTER_SETTER(Uint8, uint8_t)