diff --git a/llvm/test/MC/AArch64/udf.s b/llvm/test/MC/AArch64/udf.s
index f257157b826cd..a6a345b1ff67f 100644
--- a/llvm/test/MC/AArch64/udf.s
+++ b/llvm/test/MC/AArch64/udf.s
@@ -1,15 +1,9 @@
 # RUN: llvm-mc -assemble -show-encoding -triple=aarch64- %s | FileCheck %s
 # CHECK:  .text
 # CHECK-NEXT: udf #0      // encoding: [0x00,0x00,0x00,0x00]
-# CHECK-NEXT: udf #1      // encoding: [0x01,0x00,0x00,0x00]
-# CHECK-NEXT: udf #16     // encoding: [0x10,0x00,0x00,0x00]
-# CHECK-NEXT: udf #32     // encoding: [0x20,0x00,0x00,0x00]
-# CHECK-NEXT: udf #48     // encoding: [0x30,0x00,0x00,0x00]
-# CHECK-NEXT: udf #65535      // encoding: [0xff,0xff,0x00,0x00]
+# CHECK-NEXT: udf #513    // encoding: [0x01,0x02,0x00,0x00]
+# CHECK-NEXT: udf #65535  // encoding: [0xff,0xff,0x00,0x00]
 .text
 udf 0
-udf 1
-udf 16
-udf 32
-udf 48
+udf 513
 udf 65535
diff --git a/llvm/test/MC/Disassembler/AArch64/udf.txt b/llvm/test/MC/Disassembler/AArch64/udf.txt
index 7f8385b006285..6b3a252f19881 100644
--- a/llvm/test/MC/Disassembler/AArch64/udf.txt
+++ b/llvm/test/MC/Disassembler/AArch64/udf.txt
@@ -4,27 +4,15 @@
 # RUN: llvm-objdump -r -d --triple=arm64- - | \
 # RUN: FileCheck %s -check-prefix=OBJ
 [0x00,0x00,0x00,0x00]
-[0x01,0x00,0x00,0x00]
-[0x10,0x00,0x00,0x00]
-[0x20,0x00,0x00,0x00]
-[0x30,0x00,0x00,0x00]
+[0x01,0x02,0x00,0x00]
 [0xff,0xff,0x00,0x00]
-[0x00,0xfd,0x00,0x00]
 # CHECK: .text
 # CHECK-NEXT: udf #0
-# CHECK-NEXT: udf #1
-# CHECK-NEXT: udf #16
-# CHECK-NEXT: udf #32
-# CHECK-NEXT: udf #48
-# CHECK-NEXT: udf #32767
-# CHECK-NEXT: udf #32000
+# CHECK-NEXT: udf #513
+# CHECK-NEXT: udf #65535
 
 #OBJ: Disassembly of section .text:
 #OBJ-NEXT: $x.0:
 #OBJ-NEXT:        0:	00 00 00 00 	udf	#0
-#OBJ-NEXT:        4:	01 00 00 00 	udf	#1
-#OBJ-NEXT:        8:	10 00 00 00 	udf	#16
-#OBJ-NEXT:        c:	20 00 00 00 	udf	#32
-#OBJ-NEXT:       10:	30 00 00 00 	udf	#48
-#OBJ-NEXT:       14:	ff 7f 00 00 	udf	#32767
-#OBJ-NEXT:       18:	00 7d 00 00 	udf	#32000
+#OBJ-NEXT:        4:	01 02 00 00 	udf	#513
+#OBJ-NEXT:        8:	ff ff 00 00 	udf	#65535