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26 * GLSL linker implementation
28 * Given a set of shaders that are to be linked to generate a final program,
29 * there are three distinct stages.
31 * In the first stage shaders are partitioned into groups based on the shader
32 * type. All shaders of a particular type (e.g., vertex shaders) are linked
35 * - Undefined references in each shader are resolve to definitions in
37 * - Types and qualifiers of uniforms, outputs, and global variables defined
38 * in multiple shaders with the same name are verified to be the same.
39 * - Initializers for uniforms and global variables defined
40 * in multiple shaders with the same name are verified to be the same.
42 * The result, in the terminology of the GLSL spec, is a set of shader
43 * executables for each processing unit.
45 * After the first stage is complete, a series of semantic checks are performed
46 * on each of the shader executables.
48 * - Each shader executable must define a \c main function.
49 * - Each vertex shader executable must write to \c gl_Position.
50 * - Each fragment shader executable must write to either \c gl_FragData or
53 * In the final stage individual shader executables are linked to create a
54 * complete exectuable.
56 * - Types of uniforms defined in multiple shader stages with the same name
57 * are verified to be the same.
58 * - Initializers for uniforms defined in multiple shader stages with the
59 * same name are verified to be the same.
60 * - Types and qualifiers of outputs defined in one stage are verified to
61 * be the same as the types and qualifiers of inputs defined with the same
62 * name in a later stage.
64 * \author Ian Romanick <ian.d.romanick@intel.com>
67 #include "main/core.h"
68 #include "glsl_symbol_table.h"
71 #include "program/hash_table.h"
73 #include "ir_optimization.h"
76 #include "main/shaderobj.h"
80 * Visitor that determines whether or not a variable is ever written.
82 class find_assignment_visitor : public ir_hierarchical_visitor {
84 find_assignment_visitor(const char *name)
85 : name(name), found(false)
90 virtual ir_visitor_status visit_enter(ir_assignment *ir)
92 ir_variable *const var = ir->lhs->variable_referenced();
94 if (strcmp(name, var->name) == 0) {
99 return visit_continue_with_parent;
102 virtual ir_visitor_status visit_enter(ir_call *ir)
104 exec_list_iterator sig_iter = ir->get_callee()->parameters.iterator();
105 foreach_iter(exec_list_iterator, iter, *ir) {
106 ir_rvalue *param_rval = (ir_rvalue *)iter.get();
107 ir_variable *sig_param = (ir_variable *)sig_iter.get();
109 if (sig_param->mode == ir_var_out ||
110 sig_param->mode == ir_var_inout) {
111 ir_variable *var = param_rval->variable_referenced();
112 if (var && strcmp(name, var->name) == 0) {
120 return visit_continue_with_parent;
123 bool variable_found()
129 const char *name; /**< Find writes to a variable with this name. */
130 bool found; /**< Was a write to the variable found? */
135 * Visitor that determines whether or not a variable is ever read.
137 class find_deref_visitor : public ir_hierarchical_visitor {
139 find_deref_visitor(const char *name)
140 : name(name), found(false)
145 virtual ir_visitor_status visit(ir_dereference_variable *ir)
147 if (strcmp(this->name, ir->var->name) == 0) {
152 return visit_continue;
155 bool variable_found() const
161 const char *name; /**< Find writes to a variable with this name. */
162 bool found; /**< Was a write to the variable found? */
167 linker_error(gl_shader_program *prog, const char *fmt, ...)
171 ralloc_strcat(&prog->InfoLog, "error: ");
173 ralloc_vasprintf_append(&prog->InfoLog, fmt, ap);
176 prog->LinkStatus = false;
181 linker_warning(gl_shader_program *prog, const char *fmt, ...)
185 ralloc_strcat(&prog->InfoLog, "error: ");
187 ralloc_vasprintf_append(&prog->InfoLog, fmt, ap);
194 invalidate_variable_locations(gl_shader *sh, enum ir_variable_mode mode,
197 foreach_list(node, sh->ir) {
198 ir_variable *const var = ((ir_instruction *) node)->as_variable();
200 if ((var == NULL) || (var->mode != (unsigned) mode))
203 /* Only assign locations for generic attributes / varyings / etc.
205 if ((var->location >= generic_base) && !var->explicit_location)
212 * Determine the number of attribute slots required for a particular type
214 * This code is here because it implements the language rules of a specific
215 * GLSL version. Since it's a property of the language and not a property of
216 * types in general, it doesn't really belong in glsl_type.
219 count_attribute_slots(const glsl_type *t)
221 /* From page 31 (page 37 of the PDF) of the GLSL 1.50 spec:
223 * "A scalar input counts the same amount against this limit as a vec4,
224 * so applications may want to consider packing groups of four
225 * unrelated float inputs together into a vector to better utilize the
226 * capabilities of the underlying hardware. A matrix input will use up
227 * multiple locations. The number of locations used will equal the
228 * number of columns in the matrix."
230 * The spec does not explicitly say how arrays are counted. However, it
231 * should be safe to assume the total number of slots consumed by an array
232 * is the number of entries in the array multiplied by the number of slots
233 * consumed by a single element of the array.
237 return t->array_size() * count_attribute_slots(t->element_type());
240 return t->matrix_columns;
247 * Verify that a vertex shader executable meets all semantic requirements.
249 * Also sets prog->Vert.UsesClipDistance as a side effect.
251 * \param shader Vertex shader executable to be verified
254 validate_vertex_shader_executable(struct gl_shader_program *prog,
255 struct gl_shader *shader)
260 find_assignment_visitor find("gl_Position");
261 find.run(shader->ir);
262 if (!find.variable_found()) {
263 linker_error(prog, "vertex shader does not write to `gl_Position'\n");
267 if (prog->Version >= 130) {
268 /* From section 7.1 (Vertex Shader Special Variables) of the
271 * "It is an error for a shader to statically write both
272 * gl_ClipVertex and gl_ClipDistance."
274 find_assignment_visitor clip_vertex("gl_ClipVertex");
275 find_assignment_visitor clip_distance("gl_ClipDistance");
277 clip_vertex.run(shader->ir);
278 clip_distance.run(shader->ir);
279 if (clip_vertex.variable_found() && clip_distance.variable_found()) {
280 linker_error(prog, "vertex shader writes to both `gl_ClipVertex' "
281 "and `gl_ClipDistance'\n");
284 prog->Vert.UsesClipDistance = clip_distance.variable_found();
292 * Verify that a fragment shader executable meets all semantic requirements
294 * \param shader Fragment shader executable to be verified
297 validate_fragment_shader_executable(struct gl_shader_program *prog,
298 struct gl_shader *shader)
303 find_assignment_visitor frag_color("gl_FragColor");
304 find_assignment_visitor frag_data("gl_FragData");
306 frag_color.run(shader->ir);
307 frag_data.run(shader->ir);
309 if (frag_color.variable_found() && frag_data.variable_found()) {
310 linker_error(prog, "fragment shader writes to both "
311 "`gl_FragColor' and `gl_FragData'\n");
320 * Generate a string describing the mode of a variable
323 mode_string(const ir_variable *var)
327 return (var->read_only) ? "global constant" : "global variable";
329 case ir_var_uniform: return "uniform";
330 case ir_var_in: return "shader input";
331 case ir_var_out: return "shader output";
332 case ir_var_inout: return "shader inout";
334 case ir_var_const_in:
335 case ir_var_temporary:
337 assert(!"Should not get here.");
338 return "invalid variable";
344 * Perform validation of global variables used across multiple shaders
347 cross_validate_globals(struct gl_shader_program *prog,
348 struct gl_shader **shader_list,
349 unsigned num_shaders,
352 /* Examine all of the uniforms in all of the shaders and cross validate
355 glsl_symbol_table variables;
356 for (unsigned i = 0; i < num_shaders; i++) {
357 if (shader_list[i] == NULL)
360 foreach_list(node, shader_list[i]->ir) {
361 ir_variable *const var = ((ir_instruction *) node)->as_variable();
366 if (uniforms_only && (var->mode != ir_var_uniform))
369 /* Don't cross validate temporaries that are at global scope. These
370 * will eventually get pulled into the shaders 'main'.
372 if (var->mode == ir_var_temporary)
375 /* If a global with this name has already been seen, verify that the
376 * new instance has the same type. In addition, if the globals have
377 * initializers, the values of the initializers must be the same.
379 ir_variable *const existing = variables.get_variable(var->name);
380 if (existing != NULL) {
381 if (var->type != existing->type) {
382 /* Consider the types to be "the same" if both types are arrays
383 * of the same type and one of the arrays is implicitly sized.
384 * In addition, set the type of the linked variable to the
385 * explicitly sized array.
387 if (var->type->is_array()
388 && existing->type->is_array()
389 && (var->type->fields.array == existing->type->fields.array)
390 && ((var->type->length == 0)
391 || (existing->type->length == 0))) {
392 if (var->type->length != 0) {
393 existing->type = var->type;
396 linker_error(prog, "%s `%s' declared as type "
397 "`%s' and type `%s'\n",
399 var->name, var->type->name,
400 existing->type->name);
405 if (var->explicit_location) {
406 if (existing->explicit_location
407 && (var->location != existing->location)) {
408 linker_error(prog, "explicit locations for %s "
409 "`%s' have differing values\n",
410 mode_string(var), var->name);
414 existing->location = var->location;
415 existing->explicit_location = true;
418 /* Validate layout qualifiers for gl_FragDepth.
420 * From the AMD/ARB_conservative_depth specs:
422 * "If gl_FragDepth is redeclared in any fragment shader in a
423 * program, it must be redeclared in all fragment shaders in
424 * that program that have static assignments to
425 * gl_FragDepth. All redeclarations of gl_FragDepth in all
426 * fragment shaders in a single program must have the same set
429 if (strcmp(var->name, "gl_FragDepth") == 0) {
430 bool layout_declared = var->depth_layout != ir_depth_layout_none;
431 bool layout_differs =
432 var->depth_layout != existing->depth_layout;
434 if (layout_declared && layout_differs) {
436 "All redeclarations of gl_FragDepth in all "
437 "fragment shaders in a single program must have "
438 "the same set of qualifiers.");
441 if (var->used && layout_differs) {
443 "If gl_FragDepth is redeclared with a layout "
444 "qualifier in any fragment shader, it must be "
445 "redeclared with the same layout qualifier in "
446 "all fragment shaders that have assignments to "
451 /* FINISHME: Handle non-constant initializers.
453 if (var->constant_value != NULL) {
454 if (existing->constant_value != NULL) {
455 if (!var->constant_value->has_value(existing->constant_value)) {
456 linker_error(prog, "initializers for %s "
457 "`%s' have differing values\n",
458 mode_string(var), var->name);
462 /* If the first-seen instance of a particular uniform did not
463 * have an initializer but a later instance does, copy the
464 * initializer to the version stored in the symbol table.
466 /* FINISHME: This is wrong. The constant_value field should
467 * FINISHME: not be modified! Imagine a case where a shader
468 * FINISHME: without an initializer is linked in two different
469 * FINISHME: programs with shaders that have differing
470 * FINISHME: initializers. Linking with the first will
471 * FINISHME: modify the shader, and linking with the second
472 * FINISHME: will fail.
474 existing->constant_value =
475 var->constant_value->clone(ralloc_parent(existing), NULL);
478 if (existing->invariant != var->invariant) {
479 linker_error(prog, "declarations for %s `%s' have "
480 "mismatching invariant qualifiers\n",
481 mode_string(var), var->name);
484 if (existing->centroid != var->centroid) {
485 linker_error(prog, "declarations for %s `%s' have "
486 "mismatching centroid qualifiers\n",
487 mode_string(var), var->name);
491 variables.add_variable(var);
500 * Perform validation of uniforms used across multiple shader stages
503 cross_validate_uniforms(struct gl_shader_program *prog)
505 return cross_validate_globals(prog, prog->_LinkedShaders,
506 MESA_SHADER_TYPES, true);
511 * Validate that outputs from one stage match inputs of another
514 cross_validate_outputs_to_inputs(struct gl_shader_program *prog,
515 gl_shader *producer, gl_shader *consumer)
517 glsl_symbol_table parameters;
518 /* FINISHME: Figure these out dynamically. */
519 const char *const producer_stage = "vertex";
520 const char *const consumer_stage = "fragment";
522 /* Find all shader outputs in the "producer" stage.
524 foreach_list(node, producer->ir) {
525 ir_variable *const var = ((ir_instruction *) node)->as_variable();
527 /* FINISHME: For geometry shaders, this should also look for inout
528 * FINISHME: variables.
530 if ((var == NULL) || (var->mode != ir_var_out))
533 parameters.add_variable(var);
537 /* Find all shader inputs in the "consumer" stage. Any variables that have
538 * matching outputs already in the symbol table must have the same type and
541 foreach_list(node, consumer->ir) {
542 ir_variable *const input = ((ir_instruction *) node)->as_variable();
544 /* FINISHME: For geometry shaders, this should also look for inout
545 * FINISHME: variables.
547 if ((input == NULL) || (input->mode != ir_var_in))
550 ir_variable *const output = parameters.get_variable(input->name);
551 if (output != NULL) {
552 /* Check that the types match between stages.
554 if (input->type != output->type) {
555 /* There is a bit of a special case for gl_TexCoord. This
556 * built-in is unsized by default. Applications that variable
557 * access it must redeclare it with a size. There is some
558 * language in the GLSL spec that implies the fragment shader
559 * and vertex shader do not have to agree on this size. Other
560 * driver behave this way, and one or two applications seem to
563 * Neither declaration needs to be modified here because the array
564 * sizes are fixed later when update_array_sizes is called.
566 * From page 48 (page 54 of the PDF) of the GLSL 1.10 spec:
568 * "Unlike user-defined varying variables, the built-in
569 * varying variables don't have a strict one-to-one
570 * correspondence between the vertex language and the
571 * fragment language."
573 if (!output->type->is_array()
574 || (strncmp("gl_", output->name, 3) != 0)) {
576 "%s shader output `%s' declared as type `%s', "
577 "but %s shader input declared as type `%s'\n",
578 producer_stage, output->name,
580 consumer_stage, input->type->name);
585 /* Check that all of the qualifiers match between stages.
587 if (input->centroid != output->centroid) {
589 "%s shader output `%s' %s centroid qualifier, "
590 "but %s shader input %s centroid qualifier\n",
593 (output->centroid) ? "has" : "lacks",
595 (input->centroid) ? "has" : "lacks");
599 if (input->invariant != output->invariant) {
601 "%s shader output `%s' %s invariant qualifier, "
602 "but %s shader input %s invariant qualifier\n",
605 (output->invariant) ? "has" : "lacks",
607 (input->invariant) ? "has" : "lacks");
611 if (input->interpolation != output->interpolation) {
613 "%s shader output `%s' specifies %s "
614 "interpolation qualifier, "
615 "but %s shader input specifies %s "
616 "interpolation qualifier\n",
619 output->interpolation_string(),
621 input->interpolation_string());
632 * Populates a shaders symbol table with all global declarations
635 populate_symbol_table(gl_shader *sh)
637 sh->symbols = new(sh) glsl_symbol_table;
639 foreach_list(node, sh->ir) {
640 ir_instruction *const inst = (ir_instruction *) node;
644 if ((func = inst->as_function()) != NULL) {
645 sh->symbols->add_function(func);
646 } else if ((var = inst->as_variable()) != NULL) {
647 sh->symbols->add_variable(var);
654 * Remap variables referenced in an instruction tree
656 * This is used when instruction trees are cloned from one shader and placed in
657 * another. These trees will contain references to \c ir_variable nodes that
658 * do not exist in the target shader. This function finds these \c ir_variable
659 * references and replaces the references with matching variables in the target
662 * If there is no matching variable in the target shader, a clone of the
663 * \c ir_variable is made and added to the target shader. The new variable is
664 * added to \b both the instruction stream and the symbol table.
666 * \param inst IR tree that is to be processed.
667 * \param symbols Symbol table containing global scope symbols in the
669 * \param instructions Instruction stream where new variable declarations
673 remap_variables(ir_instruction *inst, struct gl_shader *target,
676 class remap_visitor : public ir_hierarchical_visitor {
678 remap_visitor(struct gl_shader *target,
681 this->target = target;
682 this->symbols = target->symbols;
683 this->instructions = target->ir;
687 virtual ir_visitor_status visit(ir_dereference_variable *ir)
689 if (ir->var->mode == ir_var_temporary) {
690 ir_variable *var = (ir_variable *) hash_table_find(temps, ir->var);
694 return visit_continue;
697 ir_variable *const existing =
698 this->symbols->get_variable(ir->var->name);
699 if (existing != NULL)
702 ir_variable *copy = ir->var->clone(this->target, NULL);
704 this->symbols->add_variable(copy);
705 this->instructions->push_head(copy);
709 return visit_continue;
713 struct gl_shader *target;
714 glsl_symbol_table *symbols;
715 exec_list *instructions;
719 remap_visitor v(target, temps);
726 * Move non-declarations from one instruction stream to another
728 * The intended usage pattern of this function is to pass the pointer to the
729 * head sentinel of a list (i.e., a pointer to the list cast to an \c exec_node
730 * pointer) for \c last and \c false for \c make_copies on the first
731 * call. Successive calls pass the return value of the previous call for
732 * \c last and \c true for \c make_copies.
734 * \param instructions Source instruction stream
735 * \param last Instruction after which new instructions should be
736 * inserted in the target instruction stream
737 * \param make_copies Flag selecting whether instructions in \c instructions
738 * should be copied (via \c ir_instruction::clone) into the
739 * target list or moved.
742 * The new "last" instruction in the target instruction stream. This pointer
743 * is suitable for use as the \c last parameter of a later call to this
747 move_non_declarations(exec_list *instructions, exec_node *last,
748 bool make_copies, gl_shader *target)
750 hash_table *temps = NULL;
753 temps = hash_table_ctor(0, hash_table_pointer_hash,
754 hash_table_pointer_compare);
756 foreach_list_safe(node, instructions) {
757 ir_instruction *inst = (ir_instruction *) node;
759 if (inst->as_function())
762 ir_variable *var = inst->as_variable();
763 if ((var != NULL) && (var->mode != ir_var_temporary))
766 assert(inst->as_assignment()
767 || ((var != NULL) && (var->mode == ir_var_temporary)));
770 inst = inst->clone(target, NULL);
773 hash_table_insert(temps, inst, var);
775 remap_variables(inst, target, temps);
780 last->insert_after(inst);
785 hash_table_dtor(temps);
791 * Get the function signature for main from a shader
793 static ir_function_signature *
794 get_main_function_signature(gl_shader *sh)
796 ir_function *const f = sh->symbols->get_function("main");
798 exec_list void_parameters;
800 /* Look for the 'void main()' signature and ensure that it's defined.
801 * This keeps the linker from accidentally pick a shader that just
802 * contains a prototype for main.
804 * We don't have to check for multiple definitions of main (in multiple
805 * shaders) because that would have already been caught above.
807 ir_function_signature *sig = f->matching_signature(&void_parameters);
808 if ((sig != NULL) && sig->is_defined) {
818 * Combine a group of shaders for a single stage to generate a linked shader
821 * If this function is supplied a single shader, it is cloned, and the new
822 * shader is returned.
824 static struct gl_shader *
825 link_intrastage_shaders(void *mem_ctx,
826 struct gl_context *ctx,
827 struct gl_shader_program *prog,
828 struct gl_shader **shader_list,
829 unsigned num_shaders)
831 /* Check that global variables defined in multiple shaders are consistent.
833 if (!cross_validate_globals(prog, shader_list, num_shaders, false))
836 /* Check that there is only a single definition of each function signature
837 * across all shaders.
839 for (unsigned i = 0; i < (num_shaders - 1); i++) {
840 foreach_list(node, shader_list[i]->ir) {
841 ir_function *const f = ((ir_instruction *) node)->as_function();
846 for (unsigned j = i + 1; j < num_shaders; j++) {
847 ir_function *const other =
848 shader_list[j]->symbols->get_function(f->name);
850 /* If the other shader has no function (and therefore no function
851 * signatures) with the same name, skip to the next shader.
856 foreach_iter (exec_list_iterator, iter, *f) {
857 ir_function_signature *sig =
858 (ir_function_signature *) iter.get();
860 if (!sig->is_defined || sig->is_builtin)
863 ir_function_signature *other_sig =
864 other->exact_matching_signature(& sig->parameters);
866 if ((other_sig != NULL) && other_sig->is_defined
867 && !other_sig->is_builtin) {
868 linker_error(prog, "function `%s' is multiply defined",
877 /* Find the shader that defines main, and make a clone of it.
879 * Starting with the clone, search for undefined references. If one is
880 * found, find the shader that defines it. Clone the reference and add
881 * it to the shader. Repeat until there are no undefined references or
882 * until a reference cannot be resolved.
884 gl_shader *main = NULL;
885 for (unsigned i = 0; i < num_shaders; i++) {
886 if (get_main_function_signature(shader_list[i]) != NULL) {
887 main = shader_list[i];
893 linker_error(prog, "%s shader lacks `main'\n",
894 (shader_list[0]->Type == GL_VERTEX_SHADER)
895 ? "vertex" : "fragment");
899 gl_shader *linked = ctx->Driver.NewShader(NULL, 0, main->Type);
900 linked->ir = new(linked) exec_list;
901 clone_ir_list(mem_ctx, linked->ir, main->ir);
903 populate_symbol_table(linked);
905 /* The a pointer to the main function in the final linked shader (i.e., the
906 * copy of the original shader that contained the main function).
908 ir_function_signature *const main_sig = get_main_function_signature(linked);
910 /* Move any instructions other than variable declarations or function
911 * declarations into main.
913 exec_node *insertion_point =
914 move_non_declarations(linked->ir, (exec_node *) &main_sig->body, false,
917 for (unsigned i = 0; i < num_shaders; i++) {
918 if (shader_list[i] == main)
921 insertion_point = move_non_declarations(shader_list[i]->ir,
922 insertion_point, true, linked);
925 /* Resolve initializers for global variables in the linked shader.
927 unsigned num_linking_shaders = num_shaders;
928 for (unsigned i = 0; i < num_shaders; i++)
929 num_linking_shaders += shader_list[i]->num_builtins_to_link;
931 gl_shader **linking_shaders =
932 (gl_shader **) calloc(num_linking_shaders, sizeof(gl_shader *));
934 memcpy(linking_shaders, shader_list,
935 sizeof(linking_shaders[0]) * num_shaders);
937 unsigned idx = num_shaders;
938 for (unsigned i = 0; i < num_shaders; i++) {
939 memcpy(&linking_shaders[idx], shader_list[i]->builtins_to_link,
940 sizeof(linking_shaders[0]) * shader_list[i]->num_builtins_to_link);
941 idx += shader_list[i]->num_builtins_to_link;
944 assert(idx == num_linking_shaders);
946 if (!link_function_calls(prog, linked, linking_shaders,
947 num_linking_shaders)) {
948 ctx->Driver.DeleteShader(ctx, linked);
952 free(linking_shaders);
955 /* At this point linked should contain all of the linked IR, so
956 * validate it to make sure nothing went wrong.
959 validate_ir_tree(linked->ir);
962 /* Make a pass over all variable declarations to ensure that arrays with
963 * unspecified sizes have a size specified. The size is inferred from the
964 * max_array_access field.
966 if (linked != NULL) {
967 class array_sizing_visitor : public ir_hierarchical_visitor {
969 virtual ir_visitor_status visit(ir_variable *var)
971 if (var->type->is_array() && (var->type->length == 0)) {
972 const glsl_type *type =
973 glsl_type::get_array_instance(var->type->fields.array,
974 var->max_array_access + 1);
976 assert(type != NULL);
980 return visit_continue;
991 struct uniform_node {
993 struct gl_uniform *u;
998 * Update the sizes of linked shader uniform arrays to the maximum
1001 * From page 81 (page 95 of the PDF) of the OpenGL 2.1 spec:
1003 * If one or more elements of an array are active,
1004 * GetActiveUniform will return the name of the array in name,
1005 * subject to the restrictions listed above. The type of the array
1006 * is returned in type. The size parameter contains the highest
1007 * array element index used, plus one. The compiler or linker
1008 * determines the highest index used. There will be only one
1009 * active uniform reported by the GL per uniform array.
1013 update_array_sizes(struct gl_shader_program *prog)
1015 for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
1016 if (prog->_LinkedShaders[i] == NULL)
1019 foreach_list(node, prog->_LinkedShaders[i]->ir) {
1020 ir_variable *const var = ((ir_instruction *) node)->as_variable();
1022 if ((var == NULL) || (var->mode != ir_var_uniform &&
1023 var->mode != ir_var_in &&
1024 var->mode != ir_var_out) ||
1025 !var->type->is_array())
1028 unsigned int size = var->max_array_access;
1029 for (unsigned j = 0; j < MESA_SHADER_TYPES; j++) {
1030 if (prog->_LinkedShaders[j] == NULL)
1033 foreach_list(node2, prog->_LinkedShaders[j]->ir) {
1034 ir_variable *other_var = ((ir_instruction *) node2)->as_variable();
1038 if (strcmp(var->name, other_var->name) == 0 &&
1039 other_var->max_array_access > size) {
1040 size = other_var->max_array_access;
1045 if (size + 1 != var->type->fields.array->length) {
1046 /* If this is a built-in uniform (i.e., it's backed by some
1047 * fixed-function state), adjust the number of state slots to
1048 * match the new array size. The number of slots per array entry
1049 * is not known. It seems safe to assume that the total number of
1050 * slots is an integer multiple of the number of array elements.
1051 * Determine the number of slots per array element by dividing by
1052 * the old (total) size.
1054 if (var->num_state_slots > 0) {
1055 var->num_state_slots = (size + 1)
1056 * (var->num_state_slots / var->type->length);
1059 var->type = glsl_type::get_array_instance(var->type->fields.array,
1061 /* FINISHME: We should update the types of array
1062 * dereferences of this variable now.
1070 add_uniform(void *mem_ctx, exec_list *uniforms, struct hash_table *ht,
1071 const char *name, const glsl_type *type, GLenum shader_type,
1072 unsigned *next_shader_pos, unsigned *total_uniforms)
1074 if (type->is_record()) {
1075 for (unsigned int i = 0; i < type->length; i++) {
1076 const glsl_type *field_type = type->fields.structure[i].type;
1077 char *field_name = ralloc_asprintf(mem_ctx, "%s.%s", name,
1078 type->fields.structure[i].name);
1080 add_uniform(mem_ctx, uniforms, ht, field_name, field_type,
1081 shader_type, next_shader_pos, total_uniforms);
1084 uniform_node *n = (uniform_node *) hash_table_find(ht, name);
1085 unsigned int vec4_slots;
1086 const glsl_type *array_elem_type = NULL;
1088 if (type->is_array()) {
1089 array_elem_type = type->fields.array;
1090 /* Array of structures. */
1091 if (array_elem_type->is_record()) {
1092 for (unsigned int i = 0; i < type->length; i++) {
1093 char *elem_name = ralloc_asprintf(mem_ctx, "%s[%d]", name, i);
1094 add_uniform(mem_ctx, uniforms, ht, elem_name, array_elem_type,
1095 shader_type, next_shader_pos, total_uniforms);
1101 /* Fix the storage size of samplers at 1 vec4 each. Be sure to pad out
1102 * vectors to vec4 slots.
1104 if (type->is_array()) {
1105 if (array_elem_type->is_sampler())
1106 vec4_slots = type->length;
1108 vec4_slots = type->length * array_elem_type->matrix_columns;
1109 } else if (type->is_sampler()) {
1112 vec4_slots = type->matrix_columns;
1116 n = (uniform_node *) calloc(1, sizeof(struct uniform_node));
1117 n->u = (gl_uniform *) calloc(1, sizeof(struct gl_uniform));
1118 n->slots = vec4_slots;
1120 n->u->Name = strdup(name);
1125 (*total_uniforms)++;
1127 hash_table_insert(ht, n, name);
1128 uniforms->push_tail(& n->link);
1131 switch (shader_type) {
1132 case GL_VERTEX_SHADER:
1133 n->u->VertPos = *next_shader_pos;
1135 case GL_FRAGMENT_SHADER:
1136 n->u->FragPos = *next_shader_pos;
1138 case GL_GEOMETRY_SHADER:
1139 n->u->GeomPos = *next_shader_pos;
1143 (*next_shader_pos) += vec4_slots;
1148 assign_uniform_locations(struct gl_shader_program *prog)
1152 unsigned total_uniforms = 0;
1153 hash_table *ht = hash_table_ctor(32, hash_table_string_hash,
1154 hash_table_string_compare);
1155 void *mem_ctx = ralloc_context(NULL);
1157 for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
1158 if (prog->_LinkedShaders[i] == NULL)
1161 unsigned next_position = 0;
1163 foreach_list(node, prog->_LinkedShaders[i]->ir) {
1164 ir_variable *const var = ((ir_instruction *) node)->as_variable();
1166 if ((var == NULL) || (var->mode != ir_var_uniform))
1169 if (strncmp(var->name, "gl_", 3) == 0) {
1170 /* At the moment, we don't allocate uniform locations for
1171 * builtin uniforms. It's permitted by spec, and we'll
1172 * likely switch to doing that at some point, but not yet.
1177 var->location = next_position;
1178 add_uniform(mem_ctx, &uniforms, ht, var->name, var->type,
1179 prog->_LinkedShaders[i]->Type,
1180 &next_position, &total_uniforms);
1184 ralloc_free(mem_ctx);
1186 gl_uniform_list *ul = (gl_uniform_list *)
1187 calloc(1, sizeof(gl_uniform_list));
1189 ul->Size = total_uniforms;
1190 ul->NumUniforms = total_uniforms;
1191 ul->Uniforms = (gl_uniform *) calloc(total_uniforms, sizeof(gl_uniform));
1195 for (uniform_node *node = (uniform_node *) uniforms.head
1196 ; node->link.next != NULL
1198 next = (uniform_node *) node->link.next;
1200 node->link.remove();
1201 memcpy(&ul->Uniforms[idx], node->u, sizeof(gl_uniform));
1208 hash_table_dtor(ht);
1210 prog->Uniforms = ul;
1215 * Find a contiguous set of available bits in a bitmask.
1217 * \param used_mask Bits representing used (1) and unused (0) locations
1218 * \param needed_count Number of contiguous bits needed.
1221 * Base location of the available bits on success or -1 on failure.
1224 find_available_slots(unsigned used_mask, unsigned needed_count)
1226 unsigned needed_mask = (1 << needed_count) - 1;
1227 const int max_bit_to_test = (8 * sizeof(used_mask)) - needed_count;
1229 /* The comparison to 32 is redundant, but without it GCC emits "warning:
1230 * cannot optimize possibly infinite loops" for the loop below.
1232 if ((needed_count == 0) || (max_bit_to_test < 0) || (max_bit_to_test > 32))
1235 for (int i = 0; i <= max_bit_to_test; i++) {
1236 if ((needed_mask & ~used_mask) == needed_mask)
1247 * Assign locations for either VS inputs for FS outputs
1249 * \param prog Shader program whose variables need locations assigned
1250 * \param target_index Selector for the program target to receive location
1251 * assignmnets. Must be either \c MESA_SHADER_VERTEX or
1252 * \c MESA_SHADER_FRAGMENT.
1253 * \param max_index Maximum number of generic locations. This corresponds
1254 * to either the maximum number of draw buffers or the
1255 * maximum number of generic attributes.
1258 * If locations are successfully assigned, true is returned. Otherwise an
1259 * error is emitted to the shader link log and false is returned.
1262 * Locations set via \c glBindFragDataLocation are not currently supported.
1263 * Only locations assigned automatically by the linker, explicitly set by a
1264 * layout qualifier, or explicitly set by a built-in variable (e.g., \c
1265 * gl_FragColor) are supported for fragment shaders.
1268 assign_attribute_or_color_locations(gl_shader_program *prog,
1269 unsigned target_index,
1272 /* Mark invalid locations as being used.
1274 unsigned used_locations = (max_index >= 32)
1275 ? ~0 : ~((1 << max_index) - 1);
1277 assert((target_index == MESA_SHADER_VERTEX)
1278 || (target_index == MESA_SHADER_FRAGMENT));
1280 gl_shader *const sh = prog->_LinkedShaders[target_index];
1284 /* Operate in a total of four passes.
1286 * 1. Invalidate the location assignments for all vertex shader inputs.
1288 * 2. Assign locations for inputs that have user-defined (via
1289 * glBindVertexAttribLocation) locations.
1291 * 3. Sort the attributes without assigned locations by number of slots
1292 * required in decreasing order. Fragmentation caused by attribute
1293 * locations assigned by the application may prevent large attributes
1294 * from having enough contiguous space.
1296 * 4. Assign locations to any inputs without assigned locations.
1299 const int generic_base = (target_index == MESA_SHADER_VERTEX)
1300 ? (int) VERT_ATTRIB_GENERIC0 : (int) FRAG_RESULT_DATA0;
1302 const enum ir_variable_mode direction =
1303 (target_index == MESA_SHADER_VERTEX) ? ir_var_in : ir_var_out;
1306 invalidate_variable_locations(sh, direction, generic_base);
1308 /* Temporary storage for the set of attributes that need locations assigned.
1314 /* Used below in the call to qsort. */
1315 static int compare(const void *a, const void *b)
1317 const temp_attr *const l = (const temp_attr *) a;
1318 const temp_attr *const r = (const temp_attr *) b;
1320 /* Reversed because we want a descending order sort below. */
1321 return r->slots - l->slots;
1325 unsigned num_attr = 0;
1327 foreach_list(node, sh->ir) {
1328 ir_variable *const var = ((ir_instruction *) node)->as_variable();
1330 if ((var == NULL) || (var->mode != (unsigned) direction))
1333 if (var->explicit_location) {
1334 if ((var->location >= (int)(max_index + generic_base))
1335 || (var->location < 0)) {
1337 "invalid explicit location %d specified for `%s'\n",
1339 ? var->location : var->location - generic_base,
1343 } else if (target_index == MESA_SHADER_VERTEX) {
1346 if (prog->AttributeBindings->get(binding, var->name)) {
1347 assert(binding >= VERT_ATTRIB_GENERIC0);
1348 var->location = binding;
1352 /* If the variable is not a built-in and has a location statically
1353 * assigned in the shader (presumably via a layout qualifier), make sure
1354 * that it doesn't collide with other assigned locations. Otherwise,
1355 * add it to the list of variables that need linker-assigned locations.
1357 const unsigned slots = count_attribute_slots(var->type);
1358 if (var->location != -1) {
1359 if (var->location >= generic_base) {
1360 /* From page 61 of the OpenGL 4.0 spec:
1362 * "LinkProgram will fail if the attribute bindings assigned
1363 * by BindAttribLocation do not leave not enough space to
1364 * assign a location for an active matrix attribute or an
1365 * active attribute array, both of which require multiple
1366 * contiguous generic attributes."
1368 * Previous versions of the spec contain similar language but omit
1369 * the bit about attribute arrays.
1371 * Page 61 of the OpenGL 4.0 spec also says:
1373 * "It is possible for an application to bind more than one
1374 * attribute name to the same location. This is referred to as
1375 * aliasing. This will only work if only one of the aliased
1376 * attributes is active in the executable program, or if no
1377 * path through the shader consumes more than one attribute of
1378 * a set of attributes aliased to the same location. A link
1379 * error can occur if the linker determines that every path
1380 * through the shader consumes multiple aliased attributes,
1381 * but implementations are not required to generate an error
1384 * These two paragraphs are either somewhat contradictory, or I
1385 * don't fully understand one or both of them.
1387 /* FINISHME: The code as currently written does not support
1388 * FINISHME: attribute location aliasing (see comment above).
1390 /* Mask representing the contiguous slots that will be used by
1393 const unsigned attr = var->location - generic_base;
1394 const unsigned use_mask = (1 << slots) - 1;
1396 /* Generate a link error if the set of bits requested for this
1397 * attribute overlaps any previously allocated bits.
1399 if ((~(use_mask << attr) & used_locations) != used_locations) {
1401 "insufficient contiguous attribute locations "
1402 "available for vertex shader input `%s'",
1407 used_locations |= (use_mask << attr);
1413 to_assign[num_attr].slots = slots;
1414 to_assign[num_attr].var = var;
1418 /* If all of the attributes were assigned locations by the application (or
1419 * are built-in attributes with fixed locations), return early. This should
1420 * be the common case.
1425 qsort(to_assign, num_attr, sizeof(to_assign[0]), temp_attr::compare);
1427 if (target_index == MESA_SHADER_VERTEX) {
1428 /* VERT_ATTRIB_GENERIC0 is a pseudo-alias for VERT_ATTRIB_POS. It can
1429 * only be explicitly assigned by via glBindAttribLocation. Mark it as
1430 * reserved to prevent it from being automatically allocated below.
1432 find_deref_visitor find("gl_Vertex");
1434 if (find.variable_found())
1435 used_locations |= (1 << 0);
1438 for (unsigned i = 0; i < num_attr; i++) {
1439 /* Mask representing the contiguous slots that will be used by this
1442 const unsigned use_mask = (1 << to_assign[i].slots) - 1;
1444 int location = find_available_slots(used_locations, to_assign[i].slots);
1447 const char *const string = (target_index == MESA_SHADER_VERTEX)
1448 ? "vertex shader input" : "fragment shader output";
1451 "insufficient contiguous attribute locations "
1452 "available for %s `%s'",
1453 string, to_assign[i].var->name);
1457 to_assign[i].var->location = generic_base + location;
1458 used_locations |= (use_mask << location);
1466 * Demote shader inputs and outputs that are not used in other stages
1469 demote_shader_inputs_and_outputs(gl_shader *sh, enum ir_variable_mode mode)
1471 foreach_list(node, sh->ir) {
1472 ir_variable *const var = ((ir_instruction *) node)->as_variable();
1474 if ((var == NULL) || (var->mode != int(mode)))
1477 /* A shader 'in' or 'out' variable is only really an input or output if
1478 * its value is used by other shader stages. This will cause the variable
1479 * to have a location assigned.
1481 if (var->location == -1) {
1482 var->mode = ir_var_auto;
1489 assign_varying_locations(struct gl_context *ctx,
1490 struct gl_shader_program *prog,
1491 gl_shader *producer, gl_shader *consumer)
1493 /* FINISHME: Set dynamically when geometry shader support is added. */
1494 unsigned output_index = VERT_RESULT_VAR0;
1495 unsigned input_index = FRAG_ATTRIB_VAR0;
1497 /* Operate in a total of three passes.
1499 * 1. Assign locations for any matching inputs and outputs.
1501 * 2. Mark output variables in the producer that do not have locations as
1502 * not being outputs. This lets the optimizer eliminate them.
1504 * 3. Mark input variables in the consumer that do not have locations as
1505 * not being inputs. This lets the optimizer eliminate them.
1508 invalidate_variable_locations(producer, ir_var_out, VERT_RESULT_VAR0);
1509 invalidate_variable_locations(consumer, ir_var_in, FRAG_ATTRIB_VAR0);
1511 foreach_list(node, producer->ir) {
1512 ir_variable *const output_var = ((ir_instruction *) node)->as_variable();
1514 if ((output_var == NULL) || (output_var->mode != ir_var_out)
1515 || (output_var->location != -1))
1518 ir_variable *const input_var =
1519 consumer->symbols->get_variable(output_var->name);
1521 if ((input_var == NULL) || (input_var->mode != ir_var_in))
1524 assert(input_var->location == -1);
1526 output_var->location = output_index;
1527 input_var->location = input_index;
1529 /* FINISHME: Support for "varying" records in GLSL 1.50. */
1530 assert(!output_var->type->is_record());
1532 if (output_var->type->is_array()) {
1533 const unsigned slots = output_var->type->length
1534 * output_var->type->fields.array->matrix_columns;
1536 output_index += slots;
1537 input_index += slots;
1539 const unsigned slots = output_var->type->matrix_columns;
1541 output_index += slots;
1542 input_index += slots;
1546 unsigned varying_vectors = 0;
1548 foreach_list(node, consumer->ir) {
1549 ir_variable *const var = ((ir_instruction *) node)->as_variable();
1551 if ((var == NULL) || (var->mode != ir_var_in))
1554 if (var->location == -1) {
1555 if (prog->Version <= 120) {
1556 /* On page 25 (page 31 of the PDF) of the GLSL 1.20 spec:
1558 * Only those varying variables used (i.e. read) in
1559 * the fragment shader executable must be written to
1560 * by the vertex shader executable; declaring
1561 * superfluous varying variables in a vertex shader is
1564 * We interpret this text as meaning that the VS must
1565 * write the variable for the FS to read it. See
1566 * "glsl1-varying read but not written" in piglit.
1569 linker_error(prog, "fragment shader varying %s not written "
1570 "by vertex shader\n.", var->name);
1573 /* An 'in' variable is only really a shader input if its
1574 * value is written by the previous stage.
1576 var->mode = ir_var_auto;
1578 /* The packing rules are used for vertex shader inputs are also used
1579 * for fragment shader inputs.
1581 varying_vectors += count_attribute_slots(var->type);
1585 if (ctx->API == API_OPENGLES2 || prog->Version == 100) {
1586 if (varying_vectors > ctx->Const.MaxVarying) {
1587 linker_error(prog, "shader uses too many varying vectors "
1589 varying_vectors, ctx->Const.MaxVarying);
1593 const unsigned float_components = varying_vectors * 4;
1594 if (float_components > ctx->Const.MaxVarying * 4) {
1595 linker_error(prog, "shader uses too many varying components "
1597 float_components, ctx->Const.MaxVarying * 4);
1607 link_shaders(struct gl_context *ctx, struct gl_shader_program *prog)
1609 void *mem_ctx = ralloc_context(NULL); // temporary linker context
1611 prog->LinkStatus = false;
1612 prog->Validated = false;
1613 prog->_Used = false;
1615 if (prog->InfoLog != NULL)
1616 ralloc_free(prog->InfoLog);
1618 prog->InfoLog = ralloc_strdup(NULL, "");
1620 /* Separate the shaders into groups based on their type.
1622 struct gl_shader **vert_shader_list;
1623 unsigned num_vert_shaders = 0;
1624 struct gl_shader **frag_shader_list;
1625 unsigned num_frag_shaders = 0;
1627 vert_shader_list = (struct gl_shader **)
1628 calloc(2 * prog->NumShaders, sizeof(struct gl_shader *));
1629 frag_shader_list = &vert_shader_list[prog->NumShaders];
1631 unsigned min_version = UINT_MAX;
1632 unsigned max_version = 0;
1633 for (unsigned i = 0; i < prog->NumShaders; i++) {
1634 min_version = MIN2(min_version, prog->Shaders[i]->Version);
1635 max_version = MAX2(max_version, prog->Shaders[i]->Version);
1637 switch (prog->Shaders[i]->Type) {
1638 case GL_VERTEX_SHADER:
1639 vert_shader_list[num_vert_shaders] = prog->Shaders[i];
1642 case GL_FRAGMENT_SHADER:
1643 frag_shader_list[num_frag_shaders] = prog->Shaders[i];
1646 case GL_GEOMETRY_SHADER:
1647 /* FINISHME: Support geometry shaders. */
1648 assert(prog->Shaders[i]->Type != GL_GEOMETRY_SHADER);
1653 /* Previous to GLSL version 1.30, different compilation units could mix and
1654 * match shading language versions. With GLSL 1.30 and later, the versions
1655 * of all shaders must match.
1657 assert(min_version >= 100);
1658 assert(max_version <= 130);
1659 if ((max_version >= 130 || min_version == 100)
1660 && min_version != max_version) {
1661 linker_error(prog, "all shaders must use same shading "
1662 "language version\n");
1666 prog->Version = max_version;
1668 for (unsigned int i = 0; i < MESA_SHADER_TYPES; i++) {
1669 if (prog->_LinkedShaders[i] != NULL)
1670 ctx->Driver.DeleteShader(ctx, prog->_LinkedShaders[i]);
1672 prog->_LinkedShaders[i] = NULL;
1675 /* Link all shaders for a particular stage and validate the result.
1677 if (num_vert_shaders > 0) {
1678 gl_shader *const sh =
1679 link_intrastage_shaders(mem_ctx, ctx, prog, vert_shader_list,
1685 if (!validate_vertex_shader_executable(prog, sh))
1688 _mesa_reference_shader(ctx, &prog->_LinkedShaders[MESA_SHADER_VERTEX],
1692 if (num_frag_shaders > 0) {
1693 gl_shader *const sh =
1694 link_intrastage_shaders(mem_ctx, ctx, prog, frag_shader_list,
1700 if (!validate_fragment_shader_executable(prog, sh))
1703 _mesa_reference_shader(ctx, &prog->_LinkedShaders[MESA_SHADER_FRAGMENT],
1707 /* Here begins the inter-stage linking phase. Some initial validation is
1708 * performed, then locations are assigned for uniforms, attributes, and
1711 if (cross_validate_uniforms(prog)) {
1714 for (prev = 0; prev < MESA_SHADER_TYPES; prev++) {
1715 if (prog->_LinkedShaders[prev] != NULL)
1719 /* Validate the inputs of each stage with the output of the preceding
1722 for (unsigned i = prev + 1; i < MESA_SHADER_TYPES; i++) {
1723 if (prog->_LinkedShaders[i] == NULL)
1726 if (!cross_validate_outputs_to_inputs(prog,
1727 prog->_LinkedShaders[prev],
1728 prog->_LinkedShaders[i]))
1734 prog->LinkStatus = true;
1737 /* Do common optimization before assigning storage for attributes,
1738 * uniforms, and varyings. Later optimization could possibly make
1739 * some of that unused.
1741 for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
1742 if (prog->_LinkedShaders[i] == NULL)
1745 detect_recursion_linked(prog, prog->_LinkedShaders[i]->ir);
1746 if (!prog->LinkStatus)
1749 if (ctx->ShaderCompilerOptions[i].LowerClipDistance)
1750 lower_clip_distance(prog->_LinkedShaders[i]->ir);
1752 while (do_common_optimization(prog->_LinkedShaders[i]->ir, true, false, 32))
1756 /* FINISHME: The value of the max_attribute_index parameter is
1757 * FINISHME: implementation dependent based on the value of
1758 * FINISHME: GL_MAX_VERTEX_ATTRIBS. GL_MAX_VERTEX_ATTRIBS must be
1759 * FINISHME: at least 16, so hardcode 16 for now.
1761 if (!assign_attribute_or_color_locations(prog, MESA_SHADER_VERTEX, 16)) {
1765 if (!assign_attribute_or_color_locations(prog, MESA_SHADER_FRAGMENT, ctx->Const.MaxDrawBuffers)) {
1770 for (prev = 0; prev < MESA_SHADER_TYPES; prev++) {
1771 if (prog->_LinkedShaders[prev] != NULL)
1775 for (unsigned i = prev + 1; i < MESA_SHADER_TYPES; i++) {
1776 if (prog->_LinkedShaders[i] == NULL)
1779 if (!assign_varying_locations(ctx, prog,
1780 prog->_LinkedShaders[prev],
1781 prog->_LinkedShaders[i])) {
1788 if (prog->_LinkedShaders[MESA_SHADER_VERTEX] != NULL) {
1789 demote_shader_inputs_and_outputs(prog->_LinkedShaders[MESA_SHADER_VERTEX],
1792 /* Eliminate code that is now dead due to unused vertex outputs being
1795 while (do_dead_code(prog->_LinkedShaders[MESA_SHADER_VERTEX]->ir, false))
1799 if (prog->_LinkedShaders[MESA_SHADER_GEOMETRY] != NULL) {
1800 gl_shader *const sh = prog->_LinkedShaders[MESA_SHADER_GEOMETRY];
1802 demote_shader_inputs_and_outputs(sh, ir_var_in);
1803 demote_shader_inputs_and_outputs(sh, ir_var_inout);
1804 demote_shader_inputs_and_outputs(sh, ir_var_out);
1806 /* Eliminate code that is now dead due to unused geometry outputs being
1809 while (do_dead_code(prog->_LinkedShaders[MESA_SHADER_GEOMETRY]->ir, false))
1813 if (prog->_LinkedShaders[MESA_SHADER_FRAGMENT] != NULL) {
1814 gl_shader *const sh = prog->_LinkedShaders[MESA_SHADER_FRAGMENT];
1816 demote_shader_inputs_and_outputs(sh, ir_var_in);
1818 /* Eliminate code that is now dead due to unused fragment inputs being
1819 * demoted. This shouldn't actually do anything other than remove
1820 * declarations of the (now unused) global variables.
1822 while (do_dead_code(prog->_LinkedShaders[MESA_SHADER_FRAGMENT]->ir, false))
1826 update_array_sizes(prog);
1827 assign_uniform_locations(prog);
1829 /* OpenGL ES requires that a vertex shader and a fragment shader both be
1830 * present in a linked program. By checking for use of shading language
1831 * version 1.00, we also catch the GL_ARB_ES2_compatibility case.
1833 if (!prog->InternalSeparateShader &&
1834 (ctx->API == API_OPENGLES2 || prog->Version == 100)) {
1835 if (prog->_LinkedShaders[MESA_SHADER_VERTEX] == NULL) {
1836 linker_error(prog, "program lacks a vertex shader\n");
1837 } else if (prog->_LinkedShaders[MESA_SHADER_FRAGMENT] == NULL) {
1838 linker_error(prog, "program lacks a fragment shader\n");
1842 /* FINISHME: Assign fragment shader output locations. */
1845 free(vert_shader_list);
1847 for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
1848 if (prog->_LinkedShaders[i] == NULL)
1851 /* Retain any live IR, but trash the rest. */
1852 reparent_ir(prog->_LinkedShaders[i]->ir, prog->_LinkedShaders[i]->ir);
1854 /* The symbol table in the linked shaders may contain references to
1855 * variables that were removed (e.g., unused uniforms). Since it may
1856 * contain junk, there is no possible valid use. Delete it and set the
1859 delete prog->_LinkedShaders[i]->symbols;
1860 prog->_LinkedShaders[i]->symbols = NULL;
1863 ralloc_free(mem_ctx);