diff --git a/decode.c b/decode.c
index eabe11e..49d1a93 100644
--- a/decode.c
+++ b/decode.c
@@ -349,10 +349,7 @@ direct:
 
     instr->type = desc->type;
     instr->addrsz = addr_size;
-    instr->flags = prefix_rep == 0xf3 ? FD_FLAG_REP :
-                   prefix_rep == 0xf2 ? FD_FLAG_REPNZ : 0;
-    if (mode == DECODE_64)
-        instr->flags |= FD_FLAG_64;
+    instr->flags = ((prefix_rep + 1) & 6) + (mode == DECODE_64 ? FD_FLAG_64 : 0);
     instr->address = address;
 
     for (unsigned i = 0; i < sizeof(instr->operands) / sizeof(FdOp); i++)
diff --git a/fadec.h b/fadec.h
index 4a1c338..03c4535 100644
--- a/fadec.h
+++ b/fadec.h
@@ -37,8 +37,8 @@ typedef enum {
 /** Internal use only. **/
 enum {
     FD_FLAG_LOCK = 1 << 0,
-    FD_FLAG_REP = 1 << 1,
-    FD_FLAG_REPNZ = 1 << 2,
+    FD_FLAG_REP = 1 << 2,
+    FD_FLAG_REPNZ = 1 << 1,
     FD_FLAG_64 = 1 << 7,
 };