+static void
+validate_explicit_location(const struct ast_type_qualifier *qual,
+ ir_variable *var,
+ struct _mesa_glsl_parse_state *state,
+ YYLTYPE *loc)
+{
+ bool fail = false;
+
+ /* Checks for GL_ARB_explicit_uniform_location. */
+ if (qual->flags.q.uniform) {
+ if (!state->check_explicit_uniform_location_allowed(loc, var))
+ return;
+
+ const struct gl_context *const ctx = state->ctx;
+ unsigned max_loc = qual->location + var->type->uniform_locations() - 1;
+
+ /* ARB_explicit_uniform_location specification states:
+ *
+ * "The explicitly defined locations and the generated locations
+ * must be in the range of 0 to MAX_UNIFORM_LOCATIONS minus one."
+ *
+ * "Valid locations for default-block uniform variable locations
+ * are in the range of 0 to the implementation-defined maximum
+ * number of uniform locations."
+ */
+ if (qual->location < 0) {
+ _mesa_glsl_error(loc, state,
+ "explicit location < 0 for uniform %s", var->name);
+ return;
+ }
+
+ if (max_loc >= ctx->Const.MaxUserAssignableUniformLocations) {
+ _mesa_glsl_error(loc, state, "location(s) consumed by uniform %s "
+ ">= MAX_UNIFORM_LOCATIONS (%u)", var->name,
+ ctx->Const.MaxUserAssignableUniformLocations);
+ return;
+ }
+
+ var->data.explicit_location = true;
+ var->data.location = qual->location;
+ return;
+ }
+
+ /* Between GL_ARB_explicit_attrib_location an
+ * GL_ARB_separate_shader_objects, the inputs and outputs of any shader
+ * stage can be assigned explicit locations. The checking here associates
+ * the correct extension with the correct stage's input / output:
+ *
+ * input output
+ * ----- ------
+ * vertex explicit_loc sso
+ * geometry sso sso
+ * fragment sso explicit_loc
+ */
+ switch (state->stage) {
+ case MESA_SHADER_VERTEX:
+ if (var->data.mode == ir_var_shader_in) {
+ if (!state->check_explicit_attrib_location_allowed(loc, var))
+ return;
+
+ break;
+ }
+
+ if (var->data.mode == ir_var_shader_out) {
+ if (!state->check_separate_shader_objects_allowed(loc, var))
+ return;
+
+ break;
+ }
+
+ fail = true;
+ break;
+
+ case MESA_SHADER_GEOMETRY:
+ if (var->data.mode == ir_var_shader_in || var->data.mode == ir_var_shader_out) {
+ if (!state->check_separate_shader_objects_allowed(loc, var))
+ return;
+
+ break;
+ }
+
+ fail = true;
+ break;
+
+ case MESA_SHADER_FRAGMENT:
+ if (var->data.mode == ir_var_shader_in) {
+ if (!state->check_separate_shader_objects_allowed(loc, var))
+ return;
+
+ break;
+ }
+
+ if (var->data.mode == ir_var_shader_out) {
+ if (!state->check_explicit_attrib_location_allowed(loc, var))
+ return;
+
+ break;
+ }
+
+ fail = true;
+ break;
+
+ case MESA_SHADER_COMPUTE:
+ _mesa_glsl_error(loc, state,
+ "compute shader variables cannot be given "
+ "explicit locations");
+ return;
+ };
+
+ if (fail) {
+ _mesa_glsl_error(loc, state,
+ "%s cannot be given an explicit location in %s shader",
+ mode_string(var),
+ _mesa_shader_stage_to_string(state->stage));
+ } else {
+ var->data.explicit_location = true;
+
+ /* This bit of silliness is needed because invalid explicit locations
+ * are supposed to be flagged during linking. Small negative values
+ * biased by VERT_ATTRIB_GENERIC0 or FRAG_RESULT_DATA0 could alias
+ * built-in values (e.g., -16+VERT_ATTRIB_GENERIC0 = VERT_ATTRIB_POS).
+ * The linker needs to be able to differentiate these cases. This
+ * ensures that negative values stay negative.
+ */
+ if (qual->location >= 0) {
+ switch (state->stage) {
+ case MESA_SHADER_VERTEX:
+ var->data.location = (var->data.mode == ir_var_shader_in)
+ ? (qual->location + VERT_ATTRIB_GENERIC0)
+ : (qual->location + VARYING_SLOT_VAR0);
+ break;
+
+ case MESA_SHADER_GEOMETRY:
+ var->data.location = qual->location + VARYING_SLOT_VAR0;
+ break;
+
+ case MESA_SHADER_FRAGMENT:
+ var->data.location = (var->data.mode == ir_var_shader_out)
+ ? (qual->location + FRAG_RESULT_DATA0)
+ : (qual->location + VARYING_SLOT_VAR0);
+ break;
+ case MESA_SHADER_COMPUTE:
+ assert(!"Unexpected shader type");
+ break;
+ }
+ } else {
+ var->data.location = qual->location;
+ }
+
+ if (qual->flags.q.explicit_index) {
+ /* From the GLSL 4.30 specification, section 4.4.2 (Output
+ * Layout Qualifiers):
+ *
+ * "It is also a compile-time error if a fragment shader
+ * sets a layout index to less than 0 or greater than 1."
+ *
+ * Older specifications don't mandate a behavior; we take
+ * this as a clarification and always generate the error.
+ */
+ if (qual->index < 0 || qual->index > 1) {
+ _mesa_glsl_error(loc, state,
+ "explicit index may only be 0 or 1");
+ } else {
+ var->data.explicit_index = true;
+ var->data.index = qual->index;
+ }
+ }
+ }
+}
+
+static void
+apply_image_qualifier_to_variable(const struct ast_type_qualifier *qual,
+ ir_variable *var,
+ struct _mesa_glsl_parse_state *state,
+ YYLTYPE *loc)
+{
+ const glsl_type *base_type =
+ (var->type->is_array() ? var->type->element_type() : var->type);
+
+ if (base_type->is_image()) {
+ if (var->data.mode != ir_var_uniform &&
+ var->data.mode != ir_var_function_in) {
+ _mesa_glsl_error(loc, state, "image variables may only be declared as "
+ "function parameters or uniform-qualified "
+ "global variables");
+ }
+
+ var->data.image_read_only |= qual->flags.q.read_only;
+ var->data.image_write_only |= qual->flags.q.write_only;
+ var->data.image_coherent |= qual->flags.q.coherent;
+ var->data.image_volatile |= qual->flags.q._volatile;
+ var->data.image_restrict |= qual->flags.q.restrict_flag;
+ var->data.read_only = true;
+
+ if (qual->flags.q.explicit_image_format) {
+ if (var->data.mode == ir_var_function_in) {
+ _mesa_glsl_error(loc, state, "format qualifiers cannot be "
+ "used on image function parameters");
+ }
+
+ if (qual->image_base_type != base_type->sampler_type) {
+ _mesa_glsl_error(loc, state, "format qualifier doesn't match the "
+ "base data type of the image");
+ }
+
+ var->data.image_format = qual->image_format;
+ } else {
+ if (var->data.mode == ir_var_uniform && !qual->flags.q.write_only) {
+ _mesa_glsl_error(loc, state, "uniforms not qualified with "
+ "`writeonly' must have a format layout "
+ "qualifier");
+ }
+
+ var->data.image_format = GL_NONE;
+ }
+ }
+}
+
+static inline const char*
+get_layout_qualifier_string(bool origin_upper_left, bool pixel_center_integer)
+{
+ if (origin_upper_left && pixel_center_integer)
+ return "origin_upper_left, pixel_center_integer";
+ else if (origin_upper_left)
+ return "origin_upper_left";
+ else if (pixel_center_integer)
+ return "pixel_center_integer";
+ else
+ return " ";
+}
+
+static inline bool
+is_conflicting_fragcoord_redeclaration(struct _mesa_glsl_parse_state *state,
+ const struct ast_type_qualifier *qual)
+{
+ /* If gl_FragCoord was previously declared, and the qualifiers were
+ * different in any way, return true.
+ */
+ if (state->fs_redeclares_gl_fragcoord) {
+ return (state->fs_pixel_center_integer != qual->flags.q.pixel_center_integer
+ || state->fs_origin_upper_left != qual->flags.q.origin_upper_left);
+ }
+
+ return false;
+}
+