diff --git a/src/cmd/asm/internal/asm/endtoend_test.go b/src/cmd/asm/internal/asm/endtoend_test.go
index e877a53178..d8a447d958 100644
--- a/src/cmd/asm/internal/asm/endtoend_test.go
+++ b/src/cmd/asm/internal/asm/endtoend_test.go
@@ -385,6 +385,10 @@ func TestARM64Encoder(t *testing.T) {
 	testEndToEnd(t, "arm64", "arm64enc")
 }
 
+func TestARM64Errors(t *testing.T) {
+	testErrors(t, "arm64", "arm64error")
+}
+
 func TestAMD64EndToEnd(t *testing.T) {
 	testEndToEnd(t, "amd64", "amd64")
 }
diff --git a/src/cmd/asm/internal/asm/testdata/arm64error.s b/src/cmd/asm/internal/asm/testdata/arm64error.s
new file mode 100644
index 0000000000..97af09c4dd
--- /dev/null
+++ b/src/cmd/asm/internal/asm/testdata/arm64error.s
@@ -0,0 +1,13 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+TEXT errors(SB),$0
+	MOVD.P	300(R2), R3            // ERROR "offset out of range [-255,254]"
+	MOVD.P	R3, 344(R2)            // ERROR "offset out of range [-255,254]"
+	VLD1	(R8)(R13), [V2.B16]    // ERROR "illegal combination"
+	VLD1	8(R9), [V2.B16]        // ERROR "illegal combination"
+	VST1	[V1.B16], (R8)(R13)    // ERROR "illegal combination"
+	VST1	[V1.B16], 9(R2)        // ERROR "illegal combination"
+	VLD1	8(R8)(R13), [V2.B16]   // ERROR "illegal combination"
+	RET
diff --git a/src/cmd/internal/obj/arm64/asm7.go b/src/cmd/internal/obj/arm64/asm7.go
index 824fece550..fdf1fb565d 100644
--- a/src/cmd/internal/obj/arm64/asm7.go
+++ b/src/cmd/internal/obj/arm64/asm7.go
@@ -584,6 +584,7 @@ var optab = []Optab{
 	{AVADD, C_VREG, C_NONE, C_VREG, 89, 4, 0, 0, 0},
 	{AVLD1, C_ZOREG, C_NONE, C_LIST, 81, 4, 0, 0, 0},
 	{AVLD1, C_LOREG, C_NONE, C_LIST, 81, 4, 0, 0, C_XPOST},
+	{AVLD1, C_ROFF, C_NONE, C_LIST, 81, 4, 0, 0, C_XPOST},
 	{AVMOV, C_ELEM, C_NONE, C_REG, 73, 4, 0, 0, 0},
 	{AVMOV, C_REG, C_NONE, C_ARNG, 82, 4, 0, 0, 0},
 	{AVMOV, C_ARNG, C_NONE, C_ARNG, 83, 4, 0, 0, 0},
@@ -592,6 +593,7 @@ var optab = []Optab{
 	{AVREV32, C_ARNG, C_NONE, C_ARNG, 83, 4, 0, 0, 0},
 	{AVST1, C_LIST, C_NONE, C_ZOREG, 84, 4, 0, 0, 0},
 	{AVST1, C_LIST, C_NONE, C_LOREG, 84, 4, 0, 0, C_XPOST},
+	{AVST1, C_LIST, C_NONE, C_ROFF, 84, 4, 0, 0, C_XPOST},
 	{AVDUP, C_ELEM, C_NONE, C_ARNG, 79, 4, 0, 0, 0},
 	{AVADDV, C_ARNG, C_NONE, C_VREG, 85, 4, 0, 0, 0},
 	{AVMOVI, C_ADDCON, C_NONE, C_ARNG, 86, 4, 0, 0, 0},
@@ -1268,6 +1270,12 @@ func (c *ctxt7) aclass(a *obj.Addr) int {
 			return autoclass(c.instoffset)
 
 		case obj.NAME_NONE:
+			if a.Index != 0 {
+				if a.Offset != 0 {
+					return C_GOK
+				}
+				return C_ROFF
+			}
 			c.instoffset = a.Offset
 			return oregclass(c.instoffset)
 		}
@@ -1417,7 +1425,7 @@ func (c *ctxt7) oplook(p *obj.Prog) *Optab {
 		}
 	}
 
-	c.ctxt.Diag("illegal combination %v %v %v %v, %d %d", p, DRconv(a1), DRconv(a2), DRconv(a3), p.From.Type, p.To.Type)
+	c.ctxt.Diag("illegal combination: %v %v %v %v, %d %d", p, DRconv(a1), DRconv(a2), DRconv(a3), p.From.Type, p.To.Type)
 	if ops == nil {
 		ops = optab
 	}
@@ -2523,7 +2531,7 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) {
 		v := int32(p.From.Offset)
 
 		if v < -256 || v > 255 {
-			c.ctxt.Diag("offset out of range\n%v", p)
+			c.ctxt.Diag("offset out of range [-255,254]: %v", p)
 		}
 		o1 = c.opldrpp(p, p.As)
 		if o.scond == C_XPOST {
@@ -2537,7 +2545,7 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) {
 		v := int32(p.To.Offset)
 
 		if v < -256 || v > 255 {
-			c.ctxt.Diag("offset out of range\n%v", p)
+			c.ctxt.Diag("offset out of range [-255,254]: %v", p)
 		}
 		o1 = LD2STR(c.opldrpp(p, p.As))
 		if o.scond == C_XPOST {