i965: De-duplicate is_expression_commutative() functions.

Create a backend_inst::is_commutative() method to replace two static
functions that did the exact same thing.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Topi Pohjolainen <topi.pohjolainen@intel.com>

src/mesa/drivers/dri/i965/brw_fs_cse.cpp

@@ -108,28 +108,6 @@ is_expression(const fs_inst *const inst)
    }
 }
 
-static bool
-is_expression_commutative(const fs_inst *inst)
-{
-   switch (inst->opcode) {
-   case BRW_OPCODE_AND:
-   case BRW_OPCODE_OR:
-   case BRW_OPCODE_XOR:
-   case BRW_OPCODE_ADD:
-   case BRW_OPCODE_MUL:
-      return true;
-   case BRW_OPCODE_SEL:
-      /* MIN and MAX are commutative. */
-      if (inst->conditional_mod == BRW_CONDITIONAL_GE ||
-          inst->conditional_mod == BRW_CONDITIONAL_L) {
-         return true;
-      }
-      /* fallthrough */
-   default:
-      return false;
-   }
-}
-
 static bool
 operands_match(const fs_inst *a, const fs_inst *b)
 {
@@ -140,7 +118,7 @@ operands_match(const fs_inst *a, const fs_inst *b)
       return xs[0].equals(ys[0]) &&
              ((xs[1].equals(ys[1]) && xs[2].equals(ys[2])) ||
               (xs[2].equals(ys[1]) && xs[1].equals(ys[2])));
-   } else if (!is_expression_commutative(a)) {
+   } else if (!a->is_commutative()) {
       bool match = true;
       for (int i = 0; i < a->sources; i++) {
          if (!xs[i].equals(ys[i])) {

src/mesa/drivers/dri/i965/brw_shader.cpp

@@ -768,6 +768,28 @@ backend_reg::is_accumulator() const
           fixed_hw_reg.nr == BRW_ARF_ACCUMULATOR;
 }
 
+bool
+backend_instruction::is_commutative() const
+{
+   switch (opcode) {
+   case BRW_OPCODE_AND:
+   case BRW_OPCODE_OR:
+   case BRW_OPCODE_XOR:
+   case BRW_OPCODE_ADD:
+   case BRW_OPCODE_MUL:
+      return true;
+   case BRW_OPCODE_SEL:
+      /* MIN and MAX are commutative. */
+      if (conditional_mod == BRW_CONDITIONAL_GE ||
+          conditional_mod == BRW_CONDITIONAL_L) {
+         return true;
+      }
+      /* fallthrough */
+   default:
+      return false;
+   }
+}
+
 bool
 backend_instruction::is_3src() const
 {

src/mesa/drivers/dri/i965/brw_shader.h

@@ -94,6 +94,7 @@ struct backend_instruction : public exec_node {
    bool is_tex() const;
    bool is_math() const;
    bool is_control_flow() const;
+   bool is_commutative() const;
    bool can_do_source_mods() const;
    bool can_do_saturate() const;
    bool can_do_cmod() const;

src/mesa/drivers/dri/i965/brw_vec4_cse.cpp

@@ -88,28 +88,6 @@ is_expression(const vec4_instruction *const inst)
    }
 }
 
-static bool
-is_expression_commutative(const vec4_instruction *inst)
-{
-   switch (inst->opcode) {
-   case BRW_OPCODE_AND:
-   case BRW_OPCODE_OR:
-   case BRW_OPCODE_XOR:
-   case BRW_OPCODE_ADD:
-   case BRW_OPCODE_MUL:
-      return true;
-   case BRW_OPCODE_SEL:
-      /* MIN and MAX are commutative. */
-      if (inst->conditional_mod == BRW_CONDITIONAL_GE ||
-          inst->conditional_mod == BRW_CONDITIONAL_L) {
-         return true;
-      }
-      /* fallthrough */
-   default:
-      return false;
-   }
-}
-
 static bool
 operands_match(const vec4_instruction *a, const vec4_instruction *b)
 {
@@ -120,7 +98,7 @@ operands_match(const vec4_instruction *a, const vec4_instruction *b)
       return xs[0].equals(ys[0]) &&
              ((xs[1].equals(ys[1]) && xs[2].equals(ys[2])) ||
               (xs[2].equals(ys[1]) && xs[1].equals(ys[2])));
-   } else if (!is_expression_commutative(a)) {
+   } else if (!a->is_commutative()) {
       return xs[0].equals(ys[0]) && xs[1].equals(ys[1]) && xs[2].equals(ys[2]);
    } else {
       return (xs[0].equals(ys[0]) && xs[1].equals(ys[1])) ||