Merge V8 5.2.361.47  DO NOT MERGE

https://chromium.googlesource.com/v8/v8/+/5.2.361.47

FPIIM-449

Change-Id: Ibec421b85a9b88cb3a432ada642e469fe7e78346
(cherry picked from commit bcf72ee8e3b26f1d0726869c7ddb3921c68b09a8)
diff --git a/src/compiler/x64/instruction-scheduler-x64.cc b/src/compiler/x64/instruction-scheduler-x64.cc
index 3c31965..6133bd8 100644
--- a/src/compiler/x64/instruction-scheduler-x64.cc
+++ b/src/compiler/x64/instruction-scheduler-x64.cc
@@ -168,6 +168,11 @@
     case kX64Poke:
       return kHasSideEffect;
 
+    case kX64Xchgb:
+    case kX64Xchgw:
+    case kX64Xchgl:
+      return kIsLoadOperation | kHasSideEffect;
+
 #define CASE(Name) case k##Name:
     COMMON_ARCH_OPCODE_LIST(CASE)
 #undef CASE