diff --git a/arm64/arm64asm/plan9x.go b/arm64/arm64asm/plan9x.go
index 0498b84..c9e4570 100644
--- a/arm64/arm64asm/plan9x.go
+++ b/arm64/arm64asm/plan9x.go
@@ -388,6 +388,8 @@
 
 	case UMOV:
 		op = "VMOV"
+	case NOP:
+		op = "NOOP"
 
 	default:
 		index := sort.SearchStrings(noSuffixOpSet, op)
diff --git a/arm64/arm64asm/testdata/plan9cases.txt b/arm64/arm64asm/testdata/plan9cases.txt
index 873de3d..d4a9137 100644
--- a/arm64/arm64asm/testdata/plan9cases.txt
+++ b/arm64/arm64asm/testdata/plan9cases.txt
@@ -230,7 +230,7 @@
 fe031eda|	NGC R30, R30
 e5030a7a|	NGCSW R10, R5
 f00318fa|	NGCS R24, R16
-1f2003d5|	NOP
+1f2003d5|	NOOP
 032ee42a|	ORNW R4@>11, R16, R3
 634cf6aa|	ORN R22@>19, R3, R3
 f8492d32|	ORRW $4294443071, R15, R24
@@ -1235,7 +1235,7 @@
 e6031eda|	NGC R30, R6
 e103077a|	NGCSW R7, R1
 f20301fa|	NGCS R1, R18
-1f2003d5|	NOP
+1f2003d5|	NOOP
 9347722a|	ORNW R18>>17, R28, R19
 0591e1aa|	ORN R1@>36, R8, R5
 7ba82a32|	ORRW $4290904001, R3, R27
@@ -2241,7 +2241,7 @@
 e0031dda|	NGC R29, R0
 f003167a|	NGCSW R22, R16
 e60302fa|	NGCS R2, R6
-1f2003d5|	NOP
+1f2003d5|	NOOP
 2f51732a|	ORNW R19>>20, R9, R15
 9b0facaa|	ORN R12->3, R28, R27
 efa40032|	ORRW $67044351, R7, R15
@@ -3254,7 +3254,7 @@
 f40302da|	NGC R2, R20
 ee03137a|	NGCSW R19, R14
 ee0303fa|	NGCS R3, R14
-1f2003d5|	NOP
+1f2003d5|	NOOP
 ab14e92a|	ORNW R9@>5, R5, R11
 185c3faa|	ORN ZR<<23, R0, R24
 a8850c32|	ORRW $3145776, R13, R8