diff --git a/src/arch/x86/predecoder.cc b/src/arch/x86/predecoder.cc
index 62899e65a8..ace4a6b943 100644
--- a/src/arch/x86/predecoder.cc
+++ b/src/arch/x86/predecoder.cc
@@ -69,6 +69,8 @@ namespace X86ISA
         emi.rex = 0;
         emi.legacy = 0;
         emi.opcode.num = 0;
+        emi.opcode.op = 0;
+        emi.opcode.prefixA = emi.opcode.prefixB = 0;
 
         immediateCollected = 0;
         emi.immediate = 0;