mesa: fix assertion paramList->LastUniformIndex < paramList->FirstStateVarIndex

This changes the code so that program parameters no longer have to be
sorted (meaning uniforms and constants are before state variables).

Instead of checking if the parameter is a state variable for every element,
teach all functions to handle non-state parameters safely. This is better
for the most common case where parameters are sorted or semi-sorted.

The new enum STATE_NOT_STATE_VAR identifes that a parameter is not
a state variable.

Fixes: 63f7d7dd - mesa: take advantage of sorted parameters in _mesa_load_state_parameters
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/3914

Reviewed-by: Zoltán Böszörményi <zboszor@gmail.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8046>

src/mesa/program/prog_parameter.c

@@ -326,6 +326,8 @@ _mesa_add_parameter(struct gl_program_parameter_list *paramList,
    if (state) {
       for (unsigned i = 0; i < STATE_LENGTH; i++)
          paramList->Parameters[oldNum].StateIndexes[i] = state[i];
+   } else {
+      paramList->Parameters[oldNum].StateIndexes[0] = STATE_NOT_STATE_VAR;
    }
 
    if (type == PROGRAM_UNIFORM || type == PROGRAM_CONSTANT) {
@@ -462,5 +464,4 @@ _mesa_recompute_parameter_bounds(struct gl_program_parameter_list *list)
          list->UniformBytes = MAX2(list->UniformBytes, list->NumParameterValues * 4);
       }
    }
-   assert(list->LastUniformIndex < list->FirstStateVarIndex);
 }

src/mesa/program/prog_parameter.h

@@ -148,7 +148,9 @@ struct gl_program_parameter_list
    bool DisallowRealloc;
 
    /* Parameters are optionally sorted as follows. Uniforms and constants
-    * are first, then state vars.
+    * are first, then state vars. This should be true in all cases except
+    * ir_to_mesa, which adds constants at the end, and ARB_vp with ARL,
+    * which can't sort parameters.
     */
    int UniformBytes;
    int LastUniformIndex;

src/mesa/program/prog_statevars.c

@@ -674,6 +674,12 @@ fetch_state(struct gl_context *ctx, const gl_state_index16 state[],
       }
       return;
 
+   case STATE_NOT_STATE_VAR:
+      /* Most likely PROGRAM_CONSTANT. This only happens in rare cases, e.g.
+       * ARB_vp with ARL, which can't sort parameters by type.
+       */
+      return;
+
    default:
       unreachable("Invalid state in _mesa_fetch_state");
       return;
@@ -812,6 +818,9 @@ _mesa_program_state_flags(const gl_state_index16 state[STATE_LENGTH])
 	 return 0;
       }
 
+   case STATE_NOT_STATE_VAR:
+      return 0;
+
    default:
       _mesa_problem(NULL, "unexpected state[0] in make_state_flags()");
       return 0;
@@ -1201,6 +1210,9 @@ _mesa_program_state_string(const gl_state_index16 state[STATE_LENGTH])
           state[1] == STATE_CURRENT_ATTRIB_MAYBE_VP_CLAMPED)
          append_index(str, state[2], false);
        break;
+   case STATE_NOT_STATE_VAR:
+      append(str, "not_state");
+      break;
    default:
       _mesa_problem(NULL, "Invalid state in _mesa_program_state_string");
       break;
@@ -1225,7 +1237,6 @@ _mesa_load_state_parameters(struct gl_context *ctx,
    if (!paramList)
       return;
 
-   assert(paramList->LastUniformIndex < paramList->FirstStateVarIndex);
    int num = paramList->NumParameters;
 
    for (int i = paramList->FirstStateVarIndex; i < num; i++) {
@@ -1240,7 +1251,6 @@ _mesa_upload_state_parameters(struct gl_context *ctx,
                               struct gl_program_parameter_list *paramList,
                               uint32_t *dst)
 {
-   assert(paramList->LastUniformIndex < paramList->FirstStateVarIndex);
    int num = paramList->NumParameters;
 
    for (int i = paramList->FirstStateVarIndex; i < num; i++) {
@@ -1260,15 +1270,11 @@ _mesa_upload_state_parameters(struct gl_context *ctx,
 void
 _mesa_optimize_state_parameters(struct gl_program_parameter_list *list)
 {
-   assert(list->LastUniformIndex < list->FirstStateVarIndex);
-
    for (int first_param = list->FirstStateVarIndex;
         first_param < (int)list->NumParameters; first_param++) {
       int last_param = first_param;
       int param_diff = 0;
 
-      assert(list->Parameters[first_param].Type == PROGRAM_STATE_VAR);
-
       switch (list->Parameters[first_param].StateIndexes[0]) {
       case STATE_MODELVIEW_MATRIX:
       case STATE_MODELVIEW_MATRIX_INVERSE:

src/mesa/program/prog_statevars.h

@@ -50,6 +50,8 @@ struct gl_program_parameter_list;
  * always be the array index.
  */
 typedef enum gl_state_index_ {
+   STATE_NOT_STATE_VAR = 0,
+
    STATE_MATERIAL = 100,  /* start at 100 so small ints are seen as ints */
 
    STATE_LIGHT,         /* One gl_light attribute. */