diff --git a/asm/arm64_encode.go b/asm/arm64_encode.go
index 150bd9b..70f24de 100644
--- a/asm/arm64_encode.go
+++ b/asm/arm64_encode.go
@@ -869,7 +869,9 @@ func init() {
 		"LDEORAD":  0xf8a02000,
 		"LDEORAH":  0x78a02000,
 		"LDEORALB": 0x38e02000,
+		"LDEORALD": 0xf8e02000,
 		"LDEORALH": 0x78e02000,
+		"LDEORALW": 0xb8e02000,
 		"LDEORAW":  0xb8a02000,
 		"LDEORB":   0x38202000,
 		"LDEORD":   0xf8202000,
diff --git a/asm/arm64_encode_test.go b/asm/arm64_encode_test.go
index 3c2b1a0..879bcf3 100644
--- a/asm/arm64_encode_test.go
+++ b/asm/arm64_encode_test.go
@@ -652,7 +652,8 @@ func TestArm64PairLoadStore(t *testing.T) {
 // families.
 func TestArm64AcquireRelease(t *testing.T) {
 	got := arm64Words(t, "\tLDAR (R27), R22\n\tLDARB (R25), R2\n\tLDARW (R12), R29\n\tSTLR R3, (R24)\n\tSTLRB R11, (R22)\n"+
-		"\tCASALD R5, (R6), R7\n\tLDADDALD R5, (R6), R7\n\tLDCLRALB R5, (R6), R7\n\tLDORALD R5, (RSP), R7\n\tSWPALW R5, (R6), R7\n")
+		"\tCASALD R5, (R6), R7\n\tLDADDALD R5, (R6), R7\n\tLDCLRALB R5, (R6), R7\n\tLDORALD R5, (RSP), R7\n\tSWPALW R5, (R6), R7\n"+
+		"\tLDEORALD R5, (R6), R7\n\tLDEORALW R5, (RSP), R7\n")
 	want := []uint32{
 		0xc8dfff76, // LDAR R22, (R27)
 		0x08dfff22, // LDARB R2, (R25)
@@ -664,6 +665,8 @@ func TestArm64AcquireRelease(t *testing.T) {
 		0x38e510c7, // LDCLRALB R7, (R6), R5
 		0xf8e533e7, // LDORALD R7, (RSP), R5
 		0xb8e580c7, // SWPALW R7, (R6), R5
+		0xf8e520c7, // LDEORALD R7, (R6), R5
+		0xb8e523e7, // LDEORALW R7, (RSP), R5
 		0xd65f03c0,
 	}
 	if len(got) != len(want) {