diff --git a/simplify.c b/simplify.c
index 3f39819..6e113d9 100644
--- a/simplify.c
+++ b/simplify.c
@@ -438,22 +438,24 @@ static int compare_opcode(int opcode, int inverse)
 
 static int compare_swap(int opcode)
 {
-	switch (opcode) {
-	case OP_SET_EQ:	return OP_SET_EQ;
-	case OP_SET_NE:	return OP_SET_NE;
-
-	case OP_SET_LT:	return OP_SET_GT;
-	case OP_SET_LE:	return OP_SET_GE;
-	case OP_SET_GT:	return OP_SET_LT;
-	case OP_SET_GE:	return OP_SET_LE;
-
-	case OP_SET_A:	return OP_SET_B;
-	case OP_SET_AE:	return OP_SET_BE;
-	case OP_SET_B:	return OP_SET_A;
-	case OP_SET_BE:	return OP_SET_AE;
-	default:
-		return opcode;
-	}
+
+#define CMP_OFFSET(opcode) ((opcode) - OP_BINCMP)
+	static const int swap_opcodes[CMP_OFFSET(OP_BINCMP_END) + 1] = {
+		[CMP_OFFSET(OP_SET_EQ)] = OP_SET_EQ,
+		[CMP_OFFSET(OP_SET_NE)] = OP_SET_NE,
+
+		[CMP_OFFSET(OP_SET_LT)] = OP_SET_GT,
+		[CMP_OFFSET(OP_SET_GT)] = OP_SET_LT,
+		[CMP_OFFSET(OP_SET_LE)] = OP_SET_GE,
+		[CMP_OFFSET(OP_SET_GE)] = OP_SET_LE,
+
+		[CMP_OFFSET(OP_SET_A)] = OP_SET_B,
+		[CMP_OFFSET(OP_SET_B)] = OP_SET_A,
+		[CMP_OFFSET(OP_SET_AE)] = OP_SET_BE,
+		[CMP_OFFSET(OP_SET_BE)] = OP_SET_AE,
+	};
+	assert(opcode >= OP_BINCMP && opcode <= OP_BINCMP_END);
+	return swap_opcodes[CMP_OFFSET(opcode)];
 }
 
 static int simplify_seteq_setne(struct instruction *insn, long long value)