nir/opcodes: Add algebraic properties metadata

This commit adds some algebraic properties to the metadata of each opcode
in NIR.  In particular, you now know, just from the metadata, if a given
opcode is commutative or associative.  This will be useful for algebraic
transformation passes that want to be able to match a + b as well as b + a
in one go.

v2: Make algebraic properties all caps.  This was more consistent with the
    intrinsics flags and seems better for flags in general.

    Also, the enums are now declared with (1 << n) rather then hex values.

v3: fmin and fmax technically aren't commutative or associative.  Things
    get funny when one of the arguments is a NaN.

Reviewed-by: Connor Abbott <[email protected]>

1 files changed, 8 insertions, 1 deletions

diff --git a/src/glsl/nir/nir.h b/src/glsl/nir/nir.h
index 8ff4087c240..61cdfdf8b1a 100644
--- a/src/glsl/nir/nir.h
+++ b/src/glsl/nir/nir.h
@@ -534,7 +534,7 @@ typedef struct {
 } nir_alu_dest;
 
 #define OPCODE(name, num_inputs, per_component, output_size, output_type, \
-               input_sizes, input_types) \
+               input_sizes, input_types, algebraic_props) \
    nir_op_##name,
 
 #define LAST_OPCODE(name) nir_last_opcode = nir_op_##name,
@@ -554,6 +554,11 @@ typedef enum {
    nir_type_bool
 } nir_alu_type;
 
+typedef enum {
+   NIR_OP_IS_COMMUTATIVE = (1 << 0),
+   NIR_OP_IS_ASSOCIATIVE = (1 << 1),
+} nir_op_algebraic_property;
+
 typedef struct {
    const char *name;
 
@@ -599,6 +604,8 @@ typedef struct {
     * two, and absolute value is only allowed on float type inputs.
     */
    nir_alu_type input_types[4];
+
+   nir_op_algebraic_property algebraic_properties;
 } nir_op_info;
 
 extern const nir_op_info nir_op_infos[nir_num_opcodes];