diff --git a/tools/qfcc/include/expr.h b/tools/qfcc/include/expr.h
index 007ce347a..dc4b068de 100644
--- a/tools/qfcc/include/expr.h
+++ b/tools/qfcc/include/expr.h
@@ -55,6 +55,8 @@ typedef enum {
 */
 typedef struct ex_expr_s {
 	int            op;		///< op-code of this expression
+	bool   commutative;		///< e1 and e2 can be swapped
+	bool   anticommute;		///< e1 and e2 can be swapped with negation
 	struct type_s *type;	///< the type of the result of this expression
 	struct expr_s *e1;		///< left side of binary, sole of unary
 	struct expr_s *e2;		///< right side of binary, null for unary
diff --git a/tools/qfcc/include/options.h b/tools/qfcc/include/options.h
index e0a602dc8..9ab00d08b 100644
--- a/tools/qfcc/include/options.h
+++ b/tools/qfcc/include/options.h
@@ -47,6 +47,9 @@ typedef struct {
 	bool        ifstring;			// expand if (str) to if (str != "")
 	bool        const_initializers;	// initialied globals are constant
 	bool        promote_float;		// promote float through ...
+	bool        commute_float_add;	// allow fp addition to commute
+	bool        commute_float_mul;	// allow fp multiplication to commute
+	bool        commute_float_dot;	// allow fp dot product to commute
 
 	bool        help;
 } code_options_t;
diff --git a/tools/qfcc/source/expr_algebra.c b/tools/qfcc/source/expr_algebra.c
index 46759d85f..02e071200 100644
--- a/tools/qfcc/source/expr_algebra.c
+++ b/tools/qfcc/source/expr_algebra.c
@@ -92,9 +92,7 @@ ext_expr (expr_t *src, type_t *type, int extend, bool reverse)
 static bool __attribute__((const))
 anti_com (const expr_t *e)
 {
-	return (e->type == ex_expr
-			&& (e->expr.op == CROSS || e->expr.op == WEDGE
-				|| e->expr.op == '-'));
+	return e && e->type == ex_expr && e->expr.anticommute;
 }
 
 static expr_t *
@@ -455,6 +453,8 @@ sum_expr (type_t *type, expr_t *a, expr_t *b)
 	}
 	auto sum = new_binary_expr (op, a, b);
 	sum->expr.type = type;
+	sum->expr.commutative = op == '+';
+	sum->expr.anticommute = op == '-';
 	sum = edag_add_expr (sum);
 	if (neg) {
 		sum = neg_expr (sum);
@@ -589,6 +589,7 @@ cross_expr (type_t *type, expr_t *a, expr_t *b)
 
 	auto cross = new_binary_expr (CROSS, a, b);
 	cross->expr.type = type;
+	cross->expr.anticommute = true;
 	cross = edag_add_expr (cross);
 	return cross;
 }
@@ -616,6 +617,7 @@ wedge_expr (type_t *type, expr_t *a, expr_t *b)
 	}
 	auto wedge = new_binary_expr (WEDGE, a, b);
 	wedge->expr.type = type;
+	wedge->expr.anticommute = true;
 	wedge = edag_add_expr (wedge);
 	return wedge;
 }
diff --git a/tools/qfcc/source/expr_binary.c b/tools/qfcc/source/expr_binary.c
index 065e30f62..269fa7308 100644
--- a/tools/qfcc/source/expr_binary.c
+++ b/tools/qfcc/source/expr_binary.c
@@ -44,7 +44,9 @@ typedef struct {
 	type_t     *result_type;
 	type_t     *a_cast;
 	type_t     *b_cast;
-	expr_t     *(*process)(int op, expr_t *e1, expr_t *e2);
+	expr_t   *(*process)(int op, expr_t *e1, expr_t *e2);
+	bool      (*commutative) (void);
+	bool      (*anticommute) (void);
 } expr_type_t;
 
 static expr_t *pointer_arithmetic (int op, expr_t *e1, expr_t *e2);
@@ -58,6 +60,26 @@ static expr_t *vector_multiply (int op, expr_t *e1, expr_t *e2);
 static expr_t *vector_scale (int op, expr_t *e1, expr_t *e2);
 static expr_t *entity_compare (int op, expr_t *e1, expr_t *e2);
 
+static bool always (void)
+{
+	return true;
+}
+
+static bool fp_add (void)
+{
+	return options.code.commute_float_add;
+}
+
+static bool fp_mul (void)
+{
+	return options.code.commute_float_mul;
+}
+
+static bool fp_dot (void)
+{
+	return options.code.commute_float_dot;
+}
+
 static expr_type_t string_string[] = {
 	{'+',	&type_string},
 	{EQ,	&type_int},
@@ -70,13 +92,13 @@ static expr_type_t string_string[] = {
 };
 
 static expr_type_t float_float[] = {
-	{'+',	&type_float},
-	{'-',	&type_float},
-	{'*',	&type_float},
+	{'+',	&type_float, .commutative = fp_add},
+	{'-',	&type_float, .anticommute = fp_add},
+	{'*',	&type_float, .commutative = fp_mul},
 	{'/',	&type_float},
-	{'&',	&type_float},
-	{'|',	&type_float},
-	{'^',	&type_float},
+	{'&',	&type_float, .commutative = always},
+	{'|',	&type_float, .commutative = always},
+	{'^',	&type_float, .commutative = always},
 	{'%',	&type_float},
 	{MOD,	&type_float},
 	{SHL,	&type_float},
@@ -103,13 +125,13 @@ static expr_type_t float_quat[] = {
 };
 
 static expr_type_t float_int[] = {
-	{'+',	&type_float, 0, &type_float},
-	{'-',	&type_float, 0, &type_float},
-	{'*',	&type_float, 0, &type_float},
+	{'+',	&type_float, 0, &type_float, .commutative = fp_add},
+	{'-',	&type_float, 0, &type_float, .anticommute = fp_add},
+	{'*',	&type_float, 0, &type_float, .commutative = fp_mul},
 	{'/',	&type_float, 0, &type_float},
-	{'&',	&type_float, 0, &type_float},
-	{'|',	&type_float, 0, &type_float},
-	{'^',	&type_float, 0, &type_float},
+	{'&',	&type_float, 0, &type_float, .commutative = always},
+	{'|',	&type_float, 0, &type_float, .commutative = always},
+	{'^',	&type_float, 0, &type_float, .commutative = always},
 	{'%',	&type_float, 0, &type_float},
 	{MOD,	&type_float, 0, &type_float},
 	{SHL,	&type_float, 0, &type_float},
@@ -126,9 +148,9 @@ static expr_type_t float_int[] = {
 #define float_short float_int
 
 static expr_type_t float_double[] = {
-	{'+',	&type_double, &type_double, 0},
-	{'-',	&type_double, &type_double, 0},
-	{'*',	&type_double, &type_double, 0},
+	{'+',	&type_double, &type_double, 0, .commutative = fp_add},
+	{'-',	&type_double, &type_double, 0, .anticommute = fp_add},
+	{'*',	&type_double, &type_double, 0, .commutative = fp_mul},
 	{'/',	&type_double, &type_double, 0},
 	{'%',	&type_double, &type_double, 0},
 	{MOD,	&type_double, &type_double, 0},
@@ -148,11 +170,11 @@ static expr_type_t vector_float[] = {
 };
 
 static expr_type_t vector_vector[] = {
-	{'+',	&type_vector},
-	{'-',	&type_vector},
-	{DOT,	.process = vector_dot},
-	{CROSS,	&type_vector},
-	{HADAMARD,	&type_vector},
+	{'+',	&type_vector, .commutative = fp_add},
+	{'-',	&type_vector, .anticommute = fp_add},
+	{DOT,	.process = vector_dot, .commutative = fp_dot},
+	{CROSS,	&type_vector, .anticommute = fp_add},
+	{HADAMARD,	&type_vector, .commutative = fp_mul},
 	{'*',	.process = vector_multiply},
 	{EQ,	.process = vector_compare},
 	{NE,	.process = vector_compare},
@@ -218,8 +240,8 @@ static expr_type_t quat_vector[] = {
 };
 
 static expr_type_t quat_quat[] = {
-	{'+',	&type_quaternion},
-	{'-',	&type_quaternion},
+	{'+',	&type_quaternion, .commutative = fp_add},
+	{'-',	&type_quaternion, .anticommute = fp_add},
 	{'*',	&type_quaternion},
 	{EQ,	&type_int},
 	{NE,	&type_int},
@@ -241,13 +263,13 @@ static expr_type_t quat_double[] = {
 };
 
 static expr_type_t int_float[] = {
-	{'+',	&type_float, &type_float, 0},
-	{'-',	&type_float, &type_float, 0},
-	{'*',	&type_float, &type_float, 0},
+	{'+',	&type_float, &type_float, 0, .commutative = fp_add},
+	{'-',	&type_float, &type_float, 0, .anticommute = fp_add},
+	{'*',	&type_float, &type_float, 0, .commutative = fp_mul},
 	{'/',	&type_float, &type_float, 0},
-	{'&',	&type_float, &type_float, 0},
-	{'|',	&type_float, &type_float, 0},
-	{'^',	&type_float, &type_float, 0},
+	{'&',	&type_float, &type_float, 0, .commutative = always},
+	{'|',	&type_float, &type_float, 0, .commutative = always},
+	{'^',	&type_float, &type_float, 0, .commutative = always},
 	{'%',	&type_float, &type_float, 0},
 	{MOD,	&type_float, &type_float, 0},
 	{SHL,	&type_int, 0, &type_int},	//FIXME?
@@ -277,13 +299,13 @@ static expr_type_t int_quat[] = {
 };
 
 static expr_type_t int_int[] = {
-	{'+',	&type_int},
-	{'-',	&type_int},
-	{'*',	&type_int},
+	{'+',	&type_int, .commutative = always},
+	{'-',	&type_int, .anticommute = always},
+	{'*',	&type_int, .commutative = always},
 	{'/',	&type_int},
-	{'&',	&type_int},
-	{'|',	&type_int},
-	{'^',	&type_int},
+	{'&',	&type_int, .commutative = always},
+	{'|',	&type_int, .commutative = always},
+	{'^',	&type_int, .commutative = always},
 	{'%',	&type_int},
 	{MOD,	&type_int},
 	{SHL,	&type_int},
@@ -300,13 +322,13 @@ static expr_type_t int_int[] = {
 };
 
 static expr_type_t int_uint[] = {
-	{'+',	&type_int, 0, &type_int},
-	{'-',	&type_int, 0, &type_int},
-	{'*',	&type_int, 0, &type_int},
+	{'+',	&type_int, 0, &type_int, .commutative = always},
+	{'-',	&type_int, 0, &type_int, .anticommute = always},
+	{'*',	&type_int, 0, &type_int, .commutative = always},
 	{'/',	&type_int, 0, &type_int},
-	{'&',	&type_int, 0, &type_int},
-	{'|',	&type_int, 0, &type_int},
-	{'^',	&type_int, 0, &type_int},
+	{'&',	&type_int, 0, &type_int, .commutative = always},
+	{'|',	&type_int, 0, &type_int, .commutative = always},
+	{'^',	&type_int, 0, &type_int, .commutative = always},
 	{'%',	&type_int, 0, &type_int},
 	{MOD,	&type_int, 0, &type_int},
 	{SHL,	&type_int, 0, &type_int},
@@ -321,13 +343,13 @@ static expr_type_t int_uint[] = {
 };
 
 static expr_type_t int_short[] = {
-	{'+',	&type_int, 0, &type_int},
-	{'-',	&type_int, 0, &type_int},
-	{'*',	&type_int, 0, &type_int},
+	{'+',	&type_int, 0, &type_int, .commutative = always},
+	{'-',	&type_int, 0, &type_int, .anticommute = always},
+	{'*',	&type_int, 0, &type_int, .commutative = always},
 	{'/',	&type_int, 0, &type_int},
-	{'&',	&type_int, 0, &type_int},
-	{'|',	&type_int, 0, &type_int},
-	{'^',	&type_int, 0, &type_int},
+	{'&',	&type_int, 0, &type_int, .commutative = always},
+	{'|',	&type_int, 0, &type_int, .commutative = always},
+	{'^',	&type_int, 0, &type_int, .commutative = always},
 	{'%',	&type_int, 0, &type_int},
 	{MOD,	&type_int, 0, &type_int},
 	{SHL,	&type_int, 0, &type_int},
@@ -342,9 +364,9 @@ static expr_type_t int_short[] = {
 };
 
 static expr_type_t int_double[] = {
-	{'+',	&type_double, &type_double, 0},
-	{'-',	&type_double, &type_double, 0},
-	{'*',	&type_double, &type_double, 0},
+	{'+',	&type_double, &type_double, 0, .commutative = fp_add},
+	{'-',	&type_double, &type_double, 0, .anticommute = fp_add},
+	{'*',	&type_double, &type_double, 0, .commutative = fp_mul},
 	{'/',	&type_double, &type_double, 0},
 	{'%',	&type_double, &type_double, 0},
 	{MOD,	&type_double, &type_double, 0},
@@ -363,13 +385,13 @@ static expr_type_t int_double[] = {
 #define uint_quat int_quat
 
 static expr_type_t uint_int[] = {
-	{'+',	&type_int, &type_int, &type_int },
-	{'-',	&type_int, &type_int, &type_int },
-	{'*',	&type_int, &type_int, &type_int },
+	{'+',	&type_int, &type_int, &type_int, .commutative = always},
+	{'-',	&type_int, &type_int, &type_int, .anticommute = always },
+	{'*',	&type_int, &type_int, &type_int, .commutative = always},
 	{'/',	&type_int, &type_int, &type_int },
-	{'&',	&type_int, &type_int, &type_int },
-	{'|',	&type_int, &type_int, &type_int },
-	{'^',	&type_int, &type_int, &type_int },
+	{'&',	&type_int, &type_int, &type_int, .commutative = always},
+	{'|',	&type_int, &type_int, &type_int, .commutative = always},
+	{'^',	&type_int, &type_int, &type_int, .commutative = always},
 	{'%',	&type_int, &type_int, &type_int },
 	{MOD,	&type_int, &type_int, &type_int },
 	{SHL,	&type_uint, &type_int, &type_int },
@@ -384,13 +406,13 @@ static expr_type_t uint_int[] = {
 };
 
 static expr_type_t uint_uint[] = {
-	{'+',	&type_uint},
-	{'-',	&type_uint},
-	{'*',	&type_uint},
+	{'+',	&type_uint, .commutative = always},
+	{'-',	&type_uint, .commutative = always},
+	{'*',	&type_uint, .commutative = always},
 	{'/',	&type_uint},
-	{'&',	&type_uint},
-	{'|',	&type_uint},
-	{'^',	&type_uint},
+	{'&',	&type_uint, .commutative = always},
+	{'|',	&type_uint, .commutative = always},
+	{'^',	&type_uint, .commutative = always},
 	{'%',	&type_uint},
 	{MOD,	&type_uint},
 	{SHL,	&type_uint},
@@ -412,13 +434,13 @@ static expr_type_t uint_uint[] = {
 #define short_quat int_quat
 
 static expr_type_t short_int[] = {
-	{'+',	&type_int, &type_int, 0},
-	{'-',	&type_int, &type_int, 0},
-	{'*',	&type_int, &type_int, 0},
+	{'+',	&type_int, &type_int, 0, .commutative = always},
+	{'-',	&type_int, &type_int, 0, .commutative = always},
+	{'*',	&type_int, &type_int, 0, .commutative = always},
 	{'/',	&type_int, &type_int, 0},
-	{'&',	&type_int, &type_int, 0},
-	{'|',	&type_int, &type_int, 0},
-	{'^',	&type_int, &type_int, 0},
+	{'&',	&type_int, &type_int, 0, .commutative = always},
+	{'|',	&type_int, &type_int, 0, .commutative = always},
+	{'^',	&type_int, &type_int, 0, .commutative = always},
 	{'%',	&type_int, &type_int, 0},
 	{MOD,	&type_int, &type_int, 0},
 	{SHL,	&type_short},
@@ -433,13 +455,13 @@ static expr_type_t short_int[] = {
 };
 
 static expr_type_t short_uint[] = {
-	{'+',	&type_uint, &type_uint, 0},
-	{'-',	&type_uint, &type_uint, 0},
-	{'*',	&type_uint, &type_uint, 0},
+	{'+',	&type_uint, &type_uint, 0, .commutative = always},
+	{'-',	&type_uint, &type_uint, 0, .commutative = always},
+	{'*',	&type_uint, &type_uint, 0, .commutative = always},
 	{'/',	&type_uint, &type_uint, 0},
-	{'&',	&type_uint, &type_uint, 0},
-	{'|',	&type_uint, &type_uint, 0},
-	{'^',	&type_uint, &type_uint, 0},
+	{'&',	&type_uint, &type_uint, 0, .commutative = always},
+	{'|',	&type_uint, &type_uint, 0, .commutative = always},
+	{'^',	&type_uint, &type_uint, 0, .commutative = always},
 	{'%',	&type_uint, &type_uint, 0},
 	{MOD,	&type_uint, &type_uint, 0},
 	{SHL,	&type_short},
@@ -476,9 +498,9 @@ static expr_type_t short_short[] = {
 #define short_double int_double
 
 static expr_type_t double_float[] = {
-	{'+',	&type_double, 0, &type_double},
-	{'-',	&type_double, 0, &type_double},
-	{'*',	&type_double, 0, &type_double},
+	{'+',	&type_double, 0, &type_double, .commutative = fp_add},
+	{'-',	&type_double, 0, &type_double, .anticommute = fp_add},
+	{'*',	&type_double, 0, &type_double, .commutative = fp_mul},
 	{'/',	&type_double, 0, &type_double},
 	{'%',	&type_double, 0, &type_double},
 	{MOD,	&type_double, 0, &type_double},
@@ -502,9 +524,9 @@ static expr_type_t double_quat[] = {
 };
 
 static expr_type_t double_int[] = {
-	{'+',	&type_double, 0, &type_double},
-	{'-',	&type_double, 0, &type_double},
-	{'*',	&type_double, 0, &type_double},
+	{'+',	&type_double, 0, &type_double, .commutative = fp_add},
+	{'-',	&type_double, 0, &type_double, .anticommute = fp_add},
+	{'*',	&type_double, 0, &type_double, .commutative = fp_mul},
 	{'/',	&type_double, 0, &type_double},
 	{'%',	&type_double, 0, &type_double},
 	{MOD,	&type_double, 0, &type_double},
@@ -520,9 +542,9 @@ static expr_type_t double_int[] = {
 #define double_short double_int
 
 static expr_type_t double_double[] = {
-	{'+',	&type_double},
-	{'-',	&type_double},
-	{'*',	&type_double},
+	{'+',	&type_double, .commutative = fp_add},
+	{'-',	&type_double, .anticommute = fp_add},
+	{'*',	&type_double, .commutative = fp_mul},
 	{'/',	&type_double},
 	{'%',	&type_double},
 	{MOD,	&type_double},
@@ -536,13 +558,13 @@ static expr_type_t double_double[] = {
 };
 
 static expr_type_t long_long[] = {
-	{'+',	&type_long},
-	{'-',	&type_long},
-	{'*',	&type_long},
+	{'+',	&type_long, .commutative = always},
+	{'-',	&type_long, .anticommute = fp_add},
+	{'*',	&type_long, .commutative = always},
 	{'/',	&type_long},
-	{'&',	&type_long},
-	{'|',	&type_long},
-	{'^',	&type_long},
+	{'&',	&type_long, .commutative = always},
+	{'|',	&type_long, .commutative = always},
+	{'^',	&type_long, .commutative = always},
 	{'%',	&type_long},
 	{MOD,	&type_long},
 	{SHL,	&type_long},
@@ -557,13 +579,13 @@ static expr_type_t long_long[] = {
 };
 
 static expr_type_t ulong_ulong[] = {
-	{'+',	&type_ulong},
-	{'-',	&type_ulong},
-	{'*',	&type_ulong},
+	{'+',	&type_ulong, .commutative = always},
+	{'-',	&type_ulong, .anticommute = always},
+	{'*',	&type_ulong, .commutative = always},
 	{'/',	&type_ulong},
-	{'&',	&type_ulong},
-	{'|',	&type_ulong},
-	{'^',	&type_ulong},
+	{'&',	&type_ulong, .commutative = always},
+	{'|',	&type_ulong, .commutative = always},
+	{'^',	&type_ulong, .commutative = always},
 	{'%',	&type_ulong},
 	{MOD,	&type_ulong},
 	{SHL,	&type_ulong},
@@ -1249,6 +1271,12 @@ binary_expr (int op, expr_t *e1, expr_t *e2)
 
 	e = new_binary_expr (op, e1, e2);
 	e->expr.type = expr_type->result_type;
+	if (expr_type->commutative) {
+		e->expr.commutative = expr_type->commutative ();
+	}
+	if (expr_type->anticommute) {
+		e->expr.anticommute = expr_type->anticommute ();
+	}
 	if (is_compare (op) || is_logic (op)) {
 		if (options.code.progsversion == PROG_ID_VERSION) {
 			e->expr.type = &type_float;
diff --git a/tools/qfcc/source/expr_dag.c b/tools/qfcc/source/expr_dag.c
index d726fccb2..c28bc5fb2 100644
--- a/tools/qfcc/source/expr_dag.c
+++ b/tools/qfcc/source/expr_dag.c
@@ -88,8 +88,12 @@ edag_add_expr (expr_t *expr)
 			case ex_expr:
 				if (e->expr.type == expr->expr.type
 					&& e->expr.op == expr->expr.op
-					&& e->expr.e1 == expr->expr.e1
-					&& e->expr.e2 == expr->expr.e2) {
+					&& e->expr.commutative == expr->expr.commutative
+					&& ((e->expr.e1 == expr->expr.e1
+						 && e->expr.e2 == expr->expr.e2)
+						|| (e->expr.commutative
+							&& e->expr.e1 == expr->expr.e2
+							&& e->expr.e2 == expr->expr.e1))) {
 					return e;
 				}
 				break;