diff --git a/build/zmov.go b/build/zmov.go
index 33f12de..fd8e57c 100644
--- a/build/zmov.go
+++ b/build/zmov.go
@@ -9,57 +9,57 @@ import (
 
 func (c *Context) mov(a, b operand.Op, an, bn int, t *types.Basic) {
 	switch {
-	case an == 1 && bn == 1 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 1 && bn == 1:
 		c.MOVB(a, b)
-	case an == 1 && bn == 4 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0 && an == 1 && bn == 4:
 		c.MOVBLSX(a, b)
-	case an == 1 && bn == 4 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0 && an == 1 && bn == 4:
 		c.MOVBLZX(a, b)
-	case an == 1 && bn == 8 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0 && an == 1 && bn == 8:
 		c.MOVBQSX(a, b)
-	case an == 1 && bn == 8 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0 && an == 1 && bn == 8:
 		c.MOVBQZX(a, b)
-	case an == 1 && bn == 2 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0 && an == 1 && bn == 2:
 		c.MOVBWSX(a, b)
-	case an == 1 && bn == 2 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0 && an == 1 && bn == 2:
 		c.MOVBWZX(a, b)
-	case an == 4 && bn == 4 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 4 && bn == 4:
 		c.MOVL(a, b)
-	case an == 4 && bn == 8 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0 && an == 4 && bn == 8:
 		c.MOVLQSX(a, b)
-	case an == 4 && bn == 8 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0 && an == 4 && bn == 8:
 		c.MOVLQZX(a, b)
-	case an == 16 && bn == 16 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 16 && bn == 16:
 		c.MOVOU(a, b)
-	case an == 16 && bn == 8 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 8 && bn == 8:
 		c.MOVQ(a, b)
-	case an == 8 && bn == 16 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 8 && bn == 16:
 		c.MOVQ(a, b)
-	case an == 16 && bn == 16 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 16 && bn == 8:
 		c.MOVQ(a, b)
-	case an == 8 && bn == 8 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 16 && bn == 16:
 		c.MOVQ(a, b)
-	case an == 16 && bn == 8 && (t.Info()&types.IsFloat) != 0:
+	case (t.Info()&types.IsFloat) != 0 && an == 8 && bn == 16:
 		c.MOVSD(a, b)
-	case an == 16 && bn == 16 && (t.Info()&types.IsFloat) != 0:
+	case (t.Info()&types.IsFloat) != 0 && an == 16 && bn == 8:
 		c.MOVSD(a, b)
-	case an == 8 && bn == 16 && (t.Info()&types.IsFloat) != 0:
+	case (t.Info()&types.IsFloat) != 0 && an == 16 && bn == 16:
 		c.MOVSD(a, b)
-	case an == 16 && bn == 16 && (t.Info()&types.IsFloat) != 0:
+	case (t.Info()&types.IsFloat) != 0 && an == 4 && bn == 16:
 		c.MOVSS(a, b)
-	case an == 4 && bn == 16 && (t.Info()&types.IsFloat) != 0:
+	case (t.Info()&types.IsFloat) != 0 && an == 16 && bn == 4:
 		c.MOVSS(a, b)
-	case an == 16 && bn == 4 && (t.Info()&types.IsFloat) != 0:
+	case (t.Info()&types.IsFloat) != 0 && an == 16 && bn == 16:
 		c.MOVSS(a, b)
-	case an == 2 && bn == 2 && (t.Info()&types.IsInteger) != 0:
+	case (t.Info()&types.IsInteger) != 0 && an == 2 && bn == 2:
 		c.MOVW(a, b)
-	case an == 2 && bn == 4 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0 && an == 2 && bn == 4:
 		c.MOVWLSX(a, b)
-	case an == 2 && bn == 4 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0 && an == 2 && bn == 4:
 		c.MOVWLZX(a, b)
-	case an == 2 && bn == 8 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) == 0 && an == 2 && bn == 8:
 		c.MOVWQSX(a, b)
-	case an == 2 && bn == 8 && (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0:
+	case (t.Info()&types.IsInteger) != 0 && (t.Info()&types.IsUnsigned) != 0 && an == 2 && bn == 8:
 		c.MOVWQZX(a, b)
 	default:
 		c.AddErrorMessage("could not deduce mov instruction")
diff --git a/internal/gen/mov.go b/internal/gen/mov.go
index b8cac64..26b64fa 100644
--- a/internal/gen/mov.go
+++ b/internal/gen/mov.go
@@ -3,6 +3,7 @@ package gen
 import (
 	"errors"
 	"fmt"
+	"sort"
 	"strings"
 
 	"github.com/mmcloughlin/avo/internal/inst"
@@ -57,6 +58,7 @@ func (m *mov) instruction(i inst.Instruction) {
 			cond := fmt.Sprintf("(t.Info() & %s) %s 0", c, cmp[on])
 			conds = append(conds, cond)
 		}
+		sort.Strings(conds)
 		m.Printf("case %s:\n", strings.Join(conds, " && "))
 		m.Printf("c.%s(a, b)\n", i.Opcode)
 	}
@@ -93,7 +95,9 @@ func flags(i inst.Instruction) map[string]bool {
 	return f
 }
 
-type movsize struct{ A, B int }
+type movsize struct{ A, B int8 }
+
+func (s movsize) sortkey() uint16 { return (uint16(s.A) << 8) | uint16(s.B) }
 
 func formsizes(i inst.Instruction) ([]movsize, error) {
 	set := map[movsize]bool{}
@@ -117,10 +121,11 @@ func formsizes(i inst.Instruction) ([]movsize, error) {
 	for s := range set {
 		ss = append(ss, s)
 	}
+	sort.Slice(ss, func(i, j int) bool { return ss[i].sortkey() < ss[j].sortkey() })
 	return ss, nil
 }
 
-var opsize = map[string]int{
+var opsize = map[string]int8{
 	"imm8":  -1,
 	"imm16": -1,
 	"imm32": -1,