diff --git a/src/xenia/cpu/backend/x64/x64_emitter.cc b/src/xenia/cpu/backend/x64/x64_emitter.cc
index bdb303d6a..da7909063 100644
--- a/src/xenia/cpu/backend/x64/x64_emitter.cc
+++ b/src/xenia/cpu/backend/x64/x64_emitter.cc
@@ -88,6 +88,9 @@ X64Emitter::X64Emitter(X64Backend* backend, XbyakAllocator* allocator)
     feature_flags_ |= cpu_.has(Xbyak::util::Cpu::tBMI2) ? kX64EmitBMI2 : 0;
     feature_flags_ |= cpu_.has(Xbyak::util::Cpu::tF16C) ? kX64EmitF16C : 0;
   }
+
+  // Need movbe.
+  assert_true(cpu_.has(Xbyak::util::Cpu::tMOVBE));
 }
 
 X64Emitter::~X64Emitter() = default;
diff --git a/third_party/xbyak b/third_party/xbyak
index 77a774de9..4431caffb 160000
--- a/third_party/xbyak
+++ b/third_party/xbyak
@@ -1 +1 @@
-Subproject commit 77a774de97741027a90b12fd70c6d7ac0c20a431
+Subproject commit 4431caffbb0dec5a6d8538fff67a4a875953e1ab