build: mov deduction for booleans (#341)

Updates #336

tests/fixedbugs/issue336/issue336_test.go

@@ -0,0 +1,16 @@
+package issue336
+
+import "testing"
+
+//go:generate go run asm.go -out issue336.s -stubs stub.go
+
+func TestNot(t *testing.T) {
+	nots := []func(bool) bool{Not8, Not16, Not32, Not64}
+	for _, not := range nots {
+		for _, x := range []bool{true, false} {
+			if not(x) != !x {
+				t.Fail()
+			}
+		}
+	}
+}