2 * Copyright © 2010 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
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>
68 #include "main/core.h"
69 #include "glsl_symbol_table.h"
70 #include "glsl_parser_extras.h"
73 #include "program/hash_table.h"
75 #include "link_varyings.h"
76 #include "ir_optimization.h"
77 #include "ir_rvalue_visitor.h"
78 #include "ir_uniform.h"
80 #include "main/shaderobj.h"
81 #include "main/enums.h"
84 void linker_error(gl_shader_program
*, const char *, ...);
89 * Visitor that determines whether or not a variable is ever written.
91 class find_assignment_visitor
: public ir_hierarchical_visitor
{
93 find_assignment_visitor(const char *name
)
94 : name(name
), found(false)
99 virtual ir_visitor_status
visit_enter(ir_assignment
*ir
)
101 ir_variable
*const var
= ir
->lhs
->variable_referenced();
103 if (strcmp(name
, var
->name
) == 0) {
108 return visit_continue_with_parent
;
111 virtual ir_visitor_status
visit_enter(ir_call
*ir
)
113 foreach_two_lists(formal_node
, &ir
->callee
->parameters
,
114 actual_node
, &ir
->actual_parameters
) {
115 ir_rvalue
*param_rval
= (ir_rvalue
*) actual_node
;
116 ir_variable
*sig_param
= (ir_variable
*) formal_node
;
118 if (sig_param
->data
.mode
== ir_var_function_out
||
119 sig_param
->data
.mode
== ir_var_function_inout
) {
120 ir_variable
*var
= param_rval
->variable_referenced();
121 if (var
&& strcmp(name
, var
->name
) == 0) {
128 if (ir
->return_deref
!= NULL
) {
129 ir_variable
*const var
= ir
->return_deref
->variable_referenced();
131 if (strcmp(name
, var
->name
) == 0) {
137 return visit_continue_with_parent
;
140 bool variable_found()
146 const char *name
; /**< Find writes to a variable with this name. */
147 bool found
; /**< Was a write to the variable found? */
152 * Visitor that determines whether or not a variable is ever read.
154 class find_deref_visitor
: public ir_hierarchical_visitor
{
156 find_deref_visitor(const char *name
)
157 : name(name
), found(false)
162 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
164 if (strcmp(this->name
, ir
->var
->name
) == 0) {
169 return visit_continue
;
172 bool variable_found() const
178 const char *name
; /**< Find writes to a variable with this name. */
179 bool found
; /**< Was a write to the variable found? */
183 class geom_array_resize_visitor
: public ir_hierarchical_visitor
{
185 unsigned num_vertices
;
186 gl_shader_program
*prog
;
188 geom_array_resize_visitor(unsigned num_vertices
, gl_shader_program
*prog
)
190 this->num_vertices
= num_vertices
;
194 virtual ~geom_array_resize_visitor()
199 virtual ir_visitor_status
visit(ir_variable
*var
)
201 if (!var
->type
->is_array() || var
->data
.mode
!= ir_var_shader_in
)
202 return visit_continue
;
204 unsigned size
= var
->type
->length
;
206 /* Generate a link error if the shader has declared this array with an
209 if (size
&& size
!= this->num_vertices
) {
210 linker_error(this->prog
, "size of array %s declared as %u, "
211 "but number of input vertices is %u\n",
212 var
->name
, size
, this->num_vertices
);
213 return visit_continue
;
216 /* Generate a link error if the shader attempts to access an input
217 * array using an index too large for its actual size assigned at link
220 if (var
->data
.max_array_access
>= this->num_vertices
) {
221 linker_error(this->prog
, "geometry shader accesses element %i of "
222 "%s, but only %i input vertices\n",
223 var
->data
.max_array_access
, var
->name
, this->num_vertices
);
224 return visit_continue
;
227 var
->type
= glsl_type::get_array_instance(var
->type
->element_type(),
229 var
->data
.max_array_access
= this->num_vertices
- 1;
231 return visit_continue
;
234 /* Dereferences of input variables need to be updated so that their type
235 * matches the newly assigned type of the variable they are accessing. */
236 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
238 ir
->type
= ir
->var
->type
;
239 return visit_continue
;
242 /* Dereferences of 2D input arrays need to be updated so that their type
243 * matches the newly assigned type of the array they are accessing. */
244 virtual ir_visitor_status
visit_leave(ir_dereference_array
*ir
)
246 const glsl_type
*const vt
= ir
->array
->type
;
248 ir
->type
= vt
->element_type();
249 return visit_continue
;
254 * Visitor that determines the highest stream id to which a (geometry) shader
255 * emits vertices. It also checks whether End{Stream}Primitive is ever called.
257 class find_emit_vertex_visitor
: public ir_hierarchical_visitor
{
259 find_emit_vertex_visitor(int max_allowed
)
260 : max_stream_allowed(max_allowed
),
261 invalid_stream_id(0),
262 invalid_stream_id_from_emit_vertex(false),
263 end_primitive_found(false),
264 uses_non_zero_stream(false)
269 virtual ir_visitor_status
visit_leave(ir_emit_vertex
*ir
)
271 int stream_id
= ir
->stream_id();
274 invalid_stream_id
= stream_id
;
275 invalid_stream_id_from_emit_vertex
= true;
279 if (stream_id
> max_stream_allowed
) {
280 invalid_stream_id
= stream_id
;
281 invalid_stream_id_from_emit_vertex
= true;
286 uses_non_zero_stream
= true;
288 return visit_continue
;
291 virtual ir_visitor_status
visit_leave(ir_end_primitive
*ir
)
293 end_primitive_found
= true;
295 int stream_id
= ir
->stream_id();
298 invalid_stream_id
= stream_id
;
299 invalid_stream_id_from_emit_vertex
= false;
303 if (stream_id
> max_stream_allowed
) {
304 invalid_stream_id
= stream_id
;
305 invalid_stream_id_from_emit_vertex
= false;
310 uses_non_zero_stream
= true;
312 return visit_continue
;
317 return invalid_stream_id
!= 0;
320 const char *error_func()
322 return invalid_stream_id_from_emit_vertex
?
323 "EmitStreamVertex" : "EndStreamPrimitive";
328 return invalid_stream_id
;
333 return uses_non_zero_stream
;
336 bool uses_end_primitive()
338 return end_primitive_found
;
342 int max_stream_allowed
;
343 int invalid_stream_id
;
344 bool invalid_stream_id_from_emit_vertex
;
345 bool end_primitive_found
;
346 bool uses_non_zero_stream
;
349 } /* anonymous namespace */
352 linker_error(gl_shader_program
*prog
, const char *fmt
, ...)
356 ralloc_strcat(&prog
->InfoLog
, "error: ");
358 ralloc_vasprintf_append(&prog
->InfoLog
, fmt
, ap
);
361 prog
->LinkStatus
= false;
366 linker_warning(gl_shader_program
*prog
, const char *fmt
, ...)
370 ralloc_strcat(&prog
->InfoLog
, "warning: ");
372 ralloc_vasprintf_append(&prog
->InfoLog
, fmt
, ap
);
379 * Given a string identifying a program resource, break it into a base name
380 * and an optional array index in square brackets.
382 * If an array index is present, \c out_base_name_end is set to point to the
383 * "[" that precedes the array index, and the array index itself is returned
386 * If no array index is present (or if the array index is negative or
387 * mal-formed), \c out_base_name_end, is set to point to the null terminator
388 * at the end of the input string, and -1 is returned.
390 * Only the final array index is parsed; if the string contains other array
391 * indices (or structure field accesses), they are left in the base name.
393 * No attempt is made to check that the base name is properly formed;
394 * typically the caller will look up the base name in a hash table, so
395 * ill-formed base names simply turn into hash table lookup failures.
398 parse_program_resource_name(const GLchar
*name
,
399 const GLchar
**out_base_name_end
)
401 /* Section 7.3.1 ("Program Interfaces") of the OpenGL 4.3 spec says:
403 * "When an integer array element or block instance number is part of
404 * the name string, it will be specified in decimal form without a "+"
405 * or "-" sign or any extra leading zeroes. Additionally, the name
406 * string will not include white space anywhere in the string."
409 const size_t len
= strlen(name
);
410 *out_base_name_end
= name
+ len
;
412 if (len
== 0 || name
[len
-1] != ']')
415 /* Walk backwards over the string looking for a non-digit character. This
416 * had better be the opening bracket for an array index.
418 * Initially, i specifies the location of the ']'. Since the string may
419 * contain only the ']' charcater, walk backwards very carefully.
422 for (i
= len
- 1; (i
> 0) && isdigit(name
[i
-1]); --i
)
425 if ((i
== 0) || name
[i
-1] != '[')
428 long array_index
= strtol(&name
[i
], NULL
, 10);
432 *out_base_name_end
= name
+ (i
- 1);
438 link_invalidate_variable_locations(exec_list
*ir
)
440 foreach_in_list(ir_instruction
, node
, ir
) {
441 ir_variable
*const var
= node
->as_variable();
446 /* Only assign locations for variables that lack an explicit location.
447 * Explicit locations are set for all built-in variables, generic vertex
448 * shader inputs (via layout(location=...)), and generic fragment shader
449 * outputs (also via layout(location=...)).
451 if (!var
->data
.explicit_location
) {
452 var
->data
.location
= -1;
453 var
->data
.location_frac
= 0;
456 /* ir_variable::is_unmatched_generic_inout is used by the linker while
457 * connecting outputs from one stage to inputs of the next stage.
459 * There are two implicit assumptions here. First, we assume that any
460 * built-in variable (i.e., non-generic in or out) will have
461 * explicit_location set. Second, we assume that any generic in or out
462 * will not have explicit_location set.
464 * This second assumption will only be valid until
465 * GL_ARB_separate_shader_objects is supported. When that extension is
466 * implemented, this function will need some modifications.
468 if (!var
->data
.explicit_location
) {
469 var
->data
.is_unmatched_generic_inout
= 1;
471 var
->data
.is_unmatched_generic_inout
= 0;
478 * Set UsesClipDistance and ClipDistanceArraySize based on the given shader.
480 * Also check for errors based on incorrect usage of gl_ClipVertex and
483 * Return false if an error was reported.
486 analyze_clip_usage(struct gl_shader_program
*prog
,
487 struct gl_shader
*shader
, GLboolean
*UsesClipDistance
,
488 GLuint
*ClipDistanceArraySize
)
490 *ClipDistanceArraySize
= 0;
492 if (!prog
->IsES
&& prog
->Version
>= 130) {
493 /* From section 7.1 (Vertex Shader Special Variables) of the
496 * "It is an error for a shader to statically write both
497 * gl_ClipVertex and gl_ClipDistance."
499 * This does not apply to GLSL ES shaders, since GLSL ES defines neither
500 * gl_ClipVertex nor gl_ClipDistance.
502 find_assignment_visitor
clip_vertex("gl_ClipVertex");
503 find_assignment_visitor
clip_distance("gl_ClipDistance");
505 clip_vertex
.run(shader
->ir
);
506 clip_distance
.run(shader
->ir
);
507 if (clip_vertex
.variable_found() && clip_distance
.variable_found()) {
508 linker_error(prog
, "%s shader writes to both `gl_ClipVertex' "
509 "and `gl_ClipDistance'\n",
510 _mesa_shader_stage_to_string(shader
->Stage
));
513 *UsesClipDistance
= clip_distance
.variable_found();
514 ir_variable
*clip_distance_var
=
515 shader
->symbols
->get_variable("gl_ClipDistance");
516 if (clip_distance_var
)
517 *ClipDistanceArraySize
= clip_distance_var
->type
->length
;
519 *UsesClipDistance
= false;
525 * Verify that a vertex shader executable meets all semantic requirements.
527 * Also sets prog->Vert.UsesClipDistance and prog->Vert.ClipDistanceArraySize
530 * \param shader Vertex shader executable to be verified
533 validate_vertex_shader_executable(struct gl_shader_program
*prog
,
534 struct gl_shader
*shader
)
539 /* From the GLSL 1.10 spec, page 48:
541 * "The variable gl_Position is available only in the vertex
542 * language and is intended for writing the homogeneous vertex
543 * position. All executions of a well-formed vertex shader
544 * executable must write a value into this variable. [...] The
545 * variable gl_Position is available only in the vertex
546 * language and is intended for writing the homogeneous vertex
547 * position. All executions of a well-formed vertex shader
548 * executable must write a value into this variable."
550 * while in GLSL 1.40 this text is changed to:
552 * "The variable gl_Position is available only in the vertex
553 * language and is intended for writing the homogeneous vertex
554 * position. It can be written at any time during shader
555 * execution. It may also be read back by a vertex shader
556 * after being written. This value will be used by primitive
557 * assembly, clipping, culling, and other fixed functionality
558 * operations, if present, that operate on primitives after
559 * vertex processing has occurred. Its value is undefined if
560 * the vertex shader executable does not write gl_Position."
562 * All GLSL ES Versions are similar to GLSL 1.40--failing to write to
563 * gl_Position is not an error.
565 if (prog
->Version
< (prog
->IsES
? 300 : 140)) {
566 find_assignment_visitor
find("gl_Position");
567 find
.run(shader
->ir
);
568 if (!find
.variable_found()) {
571 "vertex shader does not write to `gl_Position'."
572 "It's value is undefined. \n");
575 "vertex shader does not write to `gl_Position'. \n");
581 analyze_clip_usage(prog
, shader
, &prog
->Vert
.UsesClipDistance
,
582 &prog
->Vert
.ClipDistanceArraySize
);
587 * Verify that a fragment shader executable meets all semantic requirements
589 * \param shader Fragment shader executable to be verified
592 validate_fragment_shader_executable(struct gl_shader_program
*prog
,
593 struct gl_shader
*shader
)
598 find_assignment_visitor
frag_color("gl_FragColor");
599 find_assignment_visitor
frag_data("gl_FragData");
601 frag_color
.run(shader
->ir
);
602 frag_data
.run(shader
->ir
);
604 if (frag_color
.variable_found() && frag_data
.variable_found()) {
605 linker_error(prog
, "fragment shader writes to both "
606 "`gl_FragColor' and `gl_FragData'\n");
611 * Verify that a geometry shader executable meets all semantic requirements
613 * Also sets prog->Geom.VerticesIn, prog->Geom.UsesClipDistance, and
614 * prog->Geom.ClipDistanceArraySize as a side effect.
616 * \param shader Geometry shader executable to be verified
619 validate_geometry_shader_executable(struct gl_shader_program
*prog
,
620 struct gl_shader
*shader
)
625 unsigned num_vertices
= vertices_per_prim(prog
->Geom
.InputType
);
626 prog
->Geom
.VerticesIn
= num_vertices
;
628 analyze_clip_usage(prog
, shader
, &prog
->Geom
.UsesClipDistance
,
629 &prog
->Geom
.ClipDistanceArraySize
);
633 * Check if geometry shaders emit to non-zero streams and do corresponding
637 validate_geometry_shader_emissions(struct gl_context
*ctx
,
638 struct gl_shader_program
*prog
)
640 if (prog
->_LinkedShaders
[MESA_SHADER_GEOMETRY
] != NULL
) {
641 find_emit_vertex_visitor
emit_vertex(ctx
->Const
.MaxVertexStreams
- 1);
642 emit_vertex
.run(prog
->_LinkedShaders
[MESA_SHADER_GEOMETRY
]->ir
);
643 if (emit_vertex
.error()) {
644 linker_error(prog
, "Invalid call %s(%d). Accepted values for the "
645 "stream parameter are in the range [0, %d].\n",
646 emit_vertex
.error_func(),
647 emit_vertex
.error_stream(),
648 ctx
->Const
.MaxVertexStreams
- 1);
650 prog
->Geom
.UsesStreams
= emit_vertex
.uses_streams();
651 prog
->Geom
.UsesEndPrimitive
= emit_vertex
.uses_end_primitive();
653 /* From the ARB_gpu_shader5 spec:
655 * "Multiple vertex streams are supported only if the output primitive
656 * type is declared to be "points". A program will fail to link if it
657 * contains a geometry shader calling EmitStreamVertex() or
658 * EndStreamPrimitive() if its output primitive type is not "points".
660 * However, in the same spec:
662 * "The function EmitVertex() is equivalent to calling EmitStreamVertex()
663 * with <stream> set to zero."
667 * "The function EndPrimitive() is equivalent to calling
668 * EndStreamPrimitive() with <stream> set to zero."
670 * Since we can call EmitVertex() and EndPrimitive() when we output
671 * primitives other than points, calling EmitStreamVertex(0) or
672 * EmitEndPrimitive(0) should not produce errors. This it also what Nvidia
673 * does. Currently we only set prog->Geom.UsesStreams to TRUE when
674 * EmitStreamVertex() or EmitEndPrimitive() are called with a non-zero
677 if (prog
->Geom
.UsesStreams
&& prog
->Geom
.OutputType
!= GL_POINTS
) {
678 linker_error(prog
, "EmitStreamVertex(n) and EndStreamPrimitive(n) "
679 "with n>0 requires point output\n");
685 validate_intrastage_arrays(struct gl_shader_program
*prog
,
686 ir_variable
*const var
,
687 ir_variable
*const existing
)
689 /* Consider the types to be "the same" if both types are arrays
690 * of the same type and one of the arrays is implicitly sized.
691 * In addition, set the type of the linked variable to the
692 * explicitly sized array.
694 if (var
->type
->is_array() && existing
->type
->is_array() &&
695 (var
->type
->fields
.array
== existing
->type
->fields
.array
) &&
696 ((var
->type
->length
== 0)|| (existing
->type
->length
== 0))) {
697 if (var
->type
->length
!= 0) {
698 if (var
->type
->length
<= existing
->data
.max_array_access
) {
699 linker_error(prog
, "%s `%s' declared as type "
700 "`%s' but outermost dimension has an index"
703 var
->name
, var
->type
->name
,
704 existing
->data
.max_array_access
);
706 existing
->type
= var
->type
;
708 } else if (existing
->type
->length
!= 0) {
709 if(existing
->type
->length
<= var
->data
.max_array_access
) {
710 linker_error(prog
, "%s `%s' declared as type "
711 "`%s' but outermost dimension has an index"
714 var
->name
, existing
->type
->name
,
715 var
->data
.max_array_access
);
725 * Perform validation of global variables used across multiple shaders
728 cross_validate_globals(struct gl_shader_program
*prog
,
729 struct gl_shader
**shader_list
,
730 unsigned num_shaders
,
733 /* Examine all of the uniforms in all of the shaders and cross validate
736 glsl_symbol_table variables
;
737 for (unsigned i
= 0; i
< num_shaders
; i
++) {
738 if (shader_list
[i
] == NULL
)
741 foreach_in_list(ir_instruction
, node
, shader_list
[i
]->ir
) {
742 ir_variable
*const var
= node
->as_variable();
747 if (uniforms_only
&& (var
->data
.mode
!= ir_var_uniform
))
750 /* Don't cross validate temporaries that are at global scope. These
751 * will eventually get pulled into the shaders 'main'.
753 if (var
->data
.mode
== ir_var_temporary
)
756 /* If a global with this name has already been seen, verify that the
757 * new instance has the same type. In addition, if the globals have
758 * initializers, the values of the initializers must be the same.
760 ir_variable
*const existing
= variables
.get_variable(var
->name
);
761 if (existing
!= NULL
) {
762 /* Check if types match. Interface blocks have some special
763 * rules so we handle those elsewhere.
765 if (var
->type
!= existing
->type
&&
766 !var
->is_interface_instance()) {
767 if (!validate_intrastage_arrays(prog
, var
, existing
)) {
768 if (var
->type
->is_record() && existing
->type
->is_record()
769 && existing
->type
->record_compare(var
->type
)) {
770 existing
->type
= var
->type
;
772 linker_error(prog
, "%s `%s' declared as type "
773 "`%s' and type `%s'\n",
775 var
->name
, var
->type
->name
,
776 existing
->type
->name
);
782 if (var
->data
.explicit_location
) {
783 if (existing
->data
.explicit_location
784 && (var
->data
.location
!= existing
->data
.location
)) {
785 linker_error(prog
, "explicit locations for %s "
786 "`%s' have differing values\n",
787 mode_string(var
), var
->name
);
791 existing
->data
.location
= var
->data
.location
;
792 existing
->data
.explicit_location
= true;
795 /* From the GLSL 4.20 specification:
796 * "A link error will result if two compilation units in a program
797 * specify different integer-constant bindings for the same
798 * opaque-uniform name. However, it is not an error to specify a
799 * binding on some but not all declarations for the same name"
801 if (var
->data
.explicit_binding
) {
802 if (existing
->data
.explicit_binding
&&
803 var
->data
.binding
!= existing
->data
.binding
) {
804 linker_error(prog
, "explicit bindings for %s "
805 "`%s' have differing values\n",
806 mode_string(var
), var
->name
);
810 existing
->data
.binding
= var
->data
.binding
;
811 existing
->data
.explicit_binding
= true;
814 if (var
->type
->contains_atomic() &&
815 var
->data
.atomic
.offset
!= existing
->data
.atomic
.offset
) {
816 linker_error(prog
, "offset specifications for %s "
817 "`%s' have differing values\n",
818 mode_string(var
), var
->name
);
822 /* Validate layout qualifiers for gl_FragDepth.
824 * From the AMD/ARB_conservative_depth specs:
826 * "If gl_FragDepth is redeclared in any fragment shader in a
827 * program, it must be redeclared in all fragment shaders in
828 * that program that have static assignments to
829 * gl_FragDepth. All redeclarations of gl_FragDepth in all
830 * fragment shaders in a single program must have the same set
833 if (strcmp(var
->name
, "gl_FragDepth") == 0) {
834 bool layout_declared
= var
->data
.depth_layout
!= ir_depth_layout_none
;
835 bool layout_differs
=
836 var
->data
.depth_layout
!= existing
->data
.depth_layout
;
838 if (layout_declared
&& layout_differs
) {
840 "All redeclarations of gl_FragDepth in all "
841 "fragment shaders in a single program must have "
842 "the same set of qualifiers.\n");
845 if (var
->data
.used
&& layout_differs
) {
847 "If gl_FragDepth is redeclared with a layout "
848 "qualifier in any fragment shader, it must be "
849 "redeclared with the same layout qualifier in "
850 "all fragment shaders that have assignments to "
855 /* Page 35 (page 41 of the PDF) of the GLSL 4.20 spec says:
857 * "If a shared global has multiple initializers, the
858 * initializers must all be constant expressions, and they
859 * must all have the same value. Otherwise, a link error will
860 * result. (A shared global having only one initializer does
861 * not require that initializer to be a constant expression.)"
863 * Previous to 4.20 the GLSL spec simply said that initializers
864 * must have the same value. In this case of non-constant
865 * initializers, this was impossible to determine. As a result,
866 * no vendor actually implemented that behavior. The 4.20
867 * behavior matches the implemented behavior of at least one other
868 * vendor, so we'll implement that for all GLSL versions.
870 if (var
->constant_initializer
!= NULL
) {
871 if (existing
->constant_initializer
!= NULL
) {
872 if (!var
->constant_initializer
->has_value(existing
->constant_initializer
)) {
873 linker_error(prog
, "initializers for %s "
874 "`%s' have differing values\n",
875 mode_string(var
), var
->name
);
879 /* If the first-seen instance of a particular uniform did not
880 * have an initializer but a later instance does, copy the
881 * initializer to the version stored in the symbol table.
883 /* FINISHME: This is wrong. The constant_value field should
884 * FINISHME: not be modified! Imagine a case where a shader
885 * FINISHME: without an initializer is linked in two different
886 * FINISHME: programs with shaders that have differing
887 * FINISHME: initializers. Linking with the first will
888 * FINISHME: modify the shader, and linking with the second
889 * FINISHME: will fail.
891 existing
->constant_initializer
=
892 var
->constant_initializer
->clone(ralloc_parent(existing
),
897 if (var
->data
.has_initializer
) {
898 if (existing
->data
.has_initializer
899 && (var
->constant_initializer
== NULL
900 || existing
->constant_initializer
== NULL
)) {
902 "shared global variable `%s' has multiple "
903 "non-constant initializers.\n",
908 /* Some instance had an initializer, so keep track of that. In
909 * this location, all sorts of initializers (constant or
910 * otherwise) will propagate the existence to the variable
911 * stored in the symbol table.
913 existing
->data
.has_initializer
= true;
916 if (existing
->data
.invariant
!= var
->data
.invariant
) {
917 linker_error(prog
, "declarations for %s `%s' have "
918 "mismatching invariant qualifiers\n",
919 mode_string(var
), var
->name
);
922 if (existing
->data
.centroid
!= var
->data
.centroid
) {
923 linker_error(prog
, "declarations for %s `%s' have "
924 "mismatching centroid qualifiers\n",
925 mode_string(var
), var
->name
);
928 if (existing
->data
.sample
!= var
->data
.sample
) {
929 linker_error(prog
, "declarations for %s `%s` have "
930 "mismatching sample qualifiers\n",
931 mode_string(var
), var
->name
);
935 variables
.add_variable(var
);
942 * Perform validation of uniforms used across multiple shader stages
945 cross_validate_uniforms(struct gl_shader_program
*prog
)
947 cross_validate_globals(prog
, prog
->_LinkedShaders
,
948 MESA_SHADER_STAGES
, true);
952 * Accumulates the array of prog->UniformBlocks and checks that all
953 * definitons of blocks agree on their contents.
956 interstage_cross_validate_uniform_blocks(struct gl_shader_program
*prog
)
958 unsigned max_num_uniform_blocks
= 0;
959 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
960 if (prog
->_LinkedShaders
[i
])
961 max_num_uniform_blocks
+= prog
->_LinkedShaders
[i
]->NumUniformBlocks
;
964 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
965 struct gl_shader
*sh
= prog
->_LinkedShaders
[i
];
967 prog
->UniformBlockStageIndex
[i
] = ralloc_array(prog
, int,
968 max_num_uniform_blocks
);
969 for (unsigned int j
= 0; j
< max_num_uniform_blocks
; j
++)
970 prog
->UniformBlockStageIndex
[i
][j
] = -1;
975 for (unsigned int j
= 0; j
< sh
->NumUniformBlocks
; j
++) {
976 int index
= link_cross_validate_uniform_block(prog
,
977 &prog
->UniformBlocks
,
978 &prog
->NumUniformBlocks
,
979 &sh
->UniformBlocks
[j
]);
982 linker_error(prog
, "uniform block `%s' has mismatching definitions\n",
983 sh
->UniformBlocks
[j
].Name
);
987 prog
->UniformBlockStageIndex
[i
][index
] = j
;
996 * Populates a shaders symbol table with all global declarations
999 populate_symbol_table(gl_shader
*sh
)
1001 sh
->symbols
= new(sh
) glsl_symbol_table
;
1003 foreach_in_list(ir_instruction
, inst
, sh
->ir
) {
1007 if ((func
= inst
->as_function()) != NULL
) {
1008 sh
->symbols
->add_function(func
);
1009 } else if ((var
= inst
->as_variable()) != NULL
) {
1010 if (var
->data
.mode
!= ir_var_temporary
)
1011 sh
->symbols
->add_variable(var
);
1018 * Remap variables referenced in an instruction tree
1020 * This is used when instruction trees are cloned from one shader and placed in
1021 * another. These trees will contain references to \c ir_variable nodes that
1022 * do not exist in the target shader. This function finds these \c ir_variable
1023 * references and replaces the references with matching variables in the target
1026 * If there is no matching variable in the target shader, a clone of the
1027 * \c ir_variable is made and added to the target shader. The new variable is
1028 * added to \b both the instruction stream and the symbol table.
1030 * \param inst IR tree that is to be processed.
1031 * \param symbols Symbol table containing global scope symbols in the
1033 * \param instructions Instruction stream where new variable declarations
1037 remap_variables(ir_instruction
*inst
, struct gl_shader
*target
,
1040 class remap_visitor
: public ir_hierarchical_visitor
{
1042 remap_visitor(struct gl_shader
*target
,
1045 this->target
= target
;
1046 this->symbols
= target
->symbols
;
1047 this->instructions
= target
->ir
;
1048 this->temps
= temps
;
1051 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
1053 if (ir
->var
->data
.mode
== ir_var_temporary
) {
1054 ir_variable
*var
= (ir_variable
*) hash_table_find(temps
, ir
->var
);
1056 assert(var
!= NULL
);
1058 return visit_continue
;
1061 ir_variable
*const existing
=
1062 this->symbols
->get_variable(ir
->var
->name
);
1063 if (existing
!= NULL
)
1066 ir_variable
*copy
= ir
->var
->clone(this->target
, NULL
);
1068 this->symbols
->add_variable(copy
);
1069 this->instructions
->push_head(copy
);
1073 return visit_continue
;
1077 struct gl_shader
*target
;
1078 glsl_symbol_table
*symbols
;
1079 exec_list
*instructions
;
1083 remap_visitor
v(target
, temps
);
1090 * Move non-declarations from one instruction stream to another
1092 * The intended usage pattern of this function is to pass the pointer to the
1093 * head sentinel of a list (i.e., a pointer to the list cast to an \c exec_node
1094 * pointer) for \c last and \c false for \c make_copies on the first
1095 * call. Successive calls pass the return value of the previous call for
1096 * \c last and \c true for \c make_copies.
1098 * \param instructions Source instruction stream
1099 * \param last Instruction after which new instructions should be
1100 * inserted in the target instruction stream
1101 * \param make_copies Flag selecting whether instructions in \c instructions
1102 * should be copied (via \c ir_instruction::clone) into the
1103 * target list or moved.
1106 * The new "last" instruction in the target instruction stream. This pointer
1107 * is suitable for use as the \c last parameter of a later call to this
1111 move_non_declarations(exec_list
*instructions
, exec_node
*last
,
1112 bool make_copies
, gl_shader
*target
)
1114 hash_table
*temps
= NULL
;
1117 temps
= hash_table_ctor(0, hash_table_pointer_hash
,
1118 hash_table_pointer_compare
);
1120 foreach_in_list_safe(ir_instruction
, inst
, instructions
) {
1121 if (inst
->as_function())
1124 ir_variable
*var
= inst
->as_variable();
1125 if ((var
!= NULL
) && (var
->data
.mode
!= ir_var_temporary
))
1128 assert(inst
->as_assignment()
1130 || inst
->as_if() /* for initializers with the ?: operator */
1131 || ((var
!= NULL
) && (var
->data
.mode
== ir_var_temporary
)));
1134 inst
= inst
->clone(target
, NULL
);
1137 hash_table_insert(temps
, inst
, var
);
1139 remap_variables(inst
, target
, temps
);
1144 last
->insert_after(inst
);
1149 hash_table_dtor(temps
);
1155 * Get the function signature for main from a shader
1157 ir_function_signature
*
1158 link_get_main_function_signature(gl_shader
*sh
)
1160 ir_function
*const f
= sh
->symbols
->get_function("main");
1162 exec_list void_parameters
;
1164 /* Look for the 'void main()' signature and ensure that it's defined.
1165 * This keeps the linker from accidentally pick a shader that just
1166 * contains a prototype for main.
1168 * We don't have to check for multiple definitions of main (in multiple
1169 * shaders) because that would have already been caught above.
1171 ir_function_signature
*sig
=
1172 f
->matching_signature(NULL
, &void_parameters
, false);
1173 if ((sig
!= NULL
) && sig
->is_defined
) {
1183 * This class is only used in link_intrastage_shaders() below but declaring
1184 * it inside that function leads to compiler warnings with some versions of
1187 class array_sizing_visitor
: public ir_hierarchical_visitor
{
1189 array_sizing_visitor()
1190 : mem_ctx(ralloc_context(NULL
)),
1191 unnamed_interfaces(hash_table_ctor(0, hash_table_pointer_hash
,
1192 hash_table_pointer_compare
))
1196 ~array_sizing_visitor()
1198 hash_table_dtor(this->unnamed_interfaces
);
1199 ralloc_free(this->mem_ctx
);
1202 virtual ir_visitor_status
visit(ir_variable
*var
)
1204 fixup_type(&var
->type
, var
->data
.max_array_access
);
1205 if (var
->type
->is_interface()) {
1206 if (interface_contains_unsized_arrays(var
->type
)) {
1207 const glsl_type
*new_type
=
1208 resize_interface_members(var
->type
,
1209 var
->get_max_ifc_array_access());
1210 var
->type
= new_type
;
1211 var
->change_interface_type(new_type
);
1213 } else if (var
->type
->is_array() &&
1214 var
->type
->fields
.array
->is_interface()) {
1215 if (interface_contains_unsized_arrays(var
->type
->fields
.array
)) {
1216 const glsl_type
*new_type
=
1217 resize_interface_members(var
->type
->fields
.array
,
1218 var
->get_max_ifc_array_access());
1219 var
->change_interface_type(new_type
);
1221 glsl_type::get_array_instance(new_type
, var
->type
->length
);
1223 } else if (const glsl_type
*ifc_type
= var
->get_interface_type()) {
1224 /* Store a pointer to the variable in the unnamed_interfaces
1227 ir_variable
**interface_vars
= (ir_variable
**)
1228 hash_table_find(this->unnamed_interfaces
, ifc_type
);
1229 if (interface_vars
== NULL
) {
1230 interface_vars
= rzalloc_array(mem_ctx
, ir_variable
*,
1232 hash_table_insert(this->unnamed_interfaces
, interface_vars
,
1235 unsigned index
= ifc_type
->field_index(var
->name
);
1236 assert(index
< ifc_type
->length
);
1237 assert(interface_vars
[index
] == NULL
);
1238 interface_vars
[index
] = var
;
1240 return visit_continue
;
1244 * For each unnamed interface block that was discovered while running the
1245 * visitor, adjust the interface type to reflect the newly assigned array
1246 * sizes, and fix up the ir_variable nodes to point to the new interface
1249 void fixup_unnamed_interface_types()
1251 hash_table_call_foreach(this->unnamed_interfaces
,
1252 fixup_unnamed_interface_type
, NULL
);
1257 * If the type pointed to by \c type represents an unsized array, replace
1258 * it with a sized array whose size is determined by max_array_access.
1260 static void fixup_type(const glsl_type
**type
, unsigned max_array_access
)
1262 if ((*type
)->is_unsized_array()) {
1263 *type
= glsl_type::get_array_instance((*type
)->fields
.array
,
1264 max_array_access
+ 1);
1265 assert(*type
!= NULL
);
1270 * Determine whether the given interface type contains unsized arrays (if
1271 * it doesn't, array_sizing_visitor doesn't need to process it).
1273 static bool interface_contains_unsized_arrays(const glsl_type
*type
)
1275 for (unsigned i
= 0; i
< type
->length
; i
++) {
1276 const glsl_type
*elem_type
= type
->fields
.structure
[i
].type
;
1277 if (elem_type
->is_unsized_array())
1284 * Create a new interface type based on the given type, with unsized arrays
1285 * replaced by sized arrays whose size is determined by
1286 * max_ifc_array_access.
1288 static const glsl_type
*
1289 resize_interface_members(const glsl_type
*type
,
1290 const unsigned *max_ifc_array_access
)
1292 unsigned num_fields
= type
->length
;
1293 glsl_struct_field
*fields
= new glsl_struct_field
[num_fields
];
1294 memcpy(fields
, type
->fields
.structure
,
1295 num_fields
* sizeof(*fields
));
1296 for (unsigned i
= 0; i
< num_fields
; i
++) {
1297 fixup_type(&fields
[i
].type
, max_ifc_array_access
[i
]);
1299 glsl_interface_packing packing
=
1300 (glsl_interface_packing
) type
->interface_packing
;
1301 const glsl_type
*new_ifc_type
=
1302 glsl_type::get_interface_instance(fields
, num_fields
,
1303 packing
, type
->name
);
1305 return new_ifc_type
;
1308 static void fixup_unnamed_interface_type(const void *key
, void *data
,
1311 const glsl_type
*ifc_type
= (const glsl_type
*) key
;
1312 ir_variable
**interface_vars
= (ir_variable
**) data
;
1313 unsigned num_fields
= ifc_type
->length
;
1314 glsl_struct_field
*fields
= new glsl_struct_field
[num_fields
];
1315 memcpy(fields
, ifc_type
->fields
.structure
,
1316 num_fields
* sizeof(*fields
));
1317 bool interface_type_changed
= false;
1318 for (unsigned i
= 0; i
< num_fields
; i
++) {
1319 if (interface_vars
[i
] != NULL
&&
1320 fields
[i
].type
!= interface_vars
[i
]->type
) {
1321 fields
[i
].type
= interface_vars
[i
]->type
;
1322 interface_type_changed
= true;
1325 if (!interface_type_changed
) {
1329 glsl_interface_packing packing
=
1330 (glsl_interface_packing
) ifc_type
->interface_packing
;
1331 const glsl_type
*new_ifc_type
=
1332 glsl_type::get_interface_instance(fields
, num_fields
, packing
,
1335 for (unsigned i
= 0; i
< num_fields
; i
++) {
1336 if (interface_vars
[i
] != NULL
)
1337 interface_vars
[i
]->change_interface_type(new_ifc_type
);
1342 * Memory context used to allocate the data in \c unnamed_interfaces.
1347 * Hash table from const glsl_type * to an array of ir_variable *'s
1348 * pointing to the ir_variables constituting each unnamed interface block.
1350 hash_table
*unnamed_interfaces
;
1354 * Performs the cross-validation of layout qualifiers specified in
1355 * redeclaration of gl_FragCoord for the attached fragment shaders,
1356 * and propagates them to the linked FS and linked shader program.
1359 link_fs_input_layout_qualifiers(struct gl_shader_program
*prog
,
1360 struct gl_shader
*linked_shader
,
1361 struct gl_shader
**shader_list
,
1362 unsigned num_shaders
)
1364 linked_shader
->redeclares_gl_fragcoord
= false;
1365 linked_shader
->uses_gl_fragcoord
= false;
1366 linked_shader
->origin_upper_left
= false;
1367 linked_shader
->pixel_center_integer
= false;
1369 if (linked_shader
->Stage
!= MESA_SHADER_FRAGMENT
||
1370 (prog
->Version
< 150 && !prog
->ARB_fragment_coord_conventions_enable
))
1373 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1374 struct gl_shader
*shader
= shader_list
[i
];
1375 /* From the GLSL 1.50 spec, page 39:
1377 * "If gl_FragCoord is redeclared in any fragment shader in a program,
1378 * it must be redeclared in all the fragment shaders in that program
1379 * that have a static use gl_FragCoord."
1381 * Exclude the case when one of the 'linked_shader' or 'shader' redeclares
1382 * gl_FragCoord with no layout qualifiers but the other one doesn't
1383 * redeclare it. If we strictly follow GLSL 1.50 spec's language, it
1384 * should be a link error. But, generating link error for this case will
1385 * be a wrong behaviour which spec didn't intend to do and it could also
1386 * break some applications.
1388 if ((linked_shader
->redeclares_gl_fragcoord
1389 && !shader
->redeclares_gl_fragcoord
1390 && shader
->uses_gl_fragcoord
1391 && (linked_shader
->origin_upper_left
1392 || linked_shader
->pixel_center_integer
))
1393 || (shader
->redeclares_gl_fragcoord
1394 && !linked_shader
->redeclares_gl_fragcoord
1395 && linked_shader
->uses_gl_fragcoord
1396 && (shader
->origin_upper_left
1397 || shader
->pixel_center_integer
))) {
1398 linker_error(prog
, "fragment shader defined with conflicting "
1399 "layout qualifiers for gl_FragCoord\n");
1402 /* From the GLSL 1.50 spec, page 39:
1404 * "All redeclarations of gl_FragCoord in all fragment shaders in a
1405 * single program must have the same set of qualifiers."
1407 if (linked_shader
->redeclares_gl_fragcoord
&& shader
->redeclares_gl_fragcoord
1408 && (shader
->origin_upper_left
!= linked_shader
->origin_upper_left
1409 || shader
->pixel_center_integer
!= linked_shader
->pixel_center_integer
)) {
1410 linker_error(prog
, "fragment shader defined with conflicting "
1411 "layout qualifiers for gl_FragCoord\n");
1414 /* Update the linked shader state. Note that uses_gl_fragcoord should
1415 * accumulate the results. The other values should replace. If there
1416 * are multiple redeclarations, all the fields except uses_gl_fragcoord
1417 * are already known to be the same.
1419 if (shader
->redeclares_gl_fragcoord
|| shader
->uses_gl_fragcoord
) {
1420 linked_shader
->redeclares_gl_fragcoord
=
1421 shader
->redeclares_gl_fragcoord
;
1422 linked_shader
->uses_gl_fragcoord
= linked_shader
->uses_gl_fragcoord
1423 || shader
->uses_gl_fragcoord
;
1424 linked_shader
->origin_upper_left
= shader
->origin_upper_left
;
1425 linked_shader
->pixel_center_integer
= shader
->pixel_center_integer
;
1431 * Performs the cross-validation of geometry shader max_vertices and
1432 * primitive type layout qualifiers for the attached geometry shaders,
1433 * and propagates them to the linked GS and linked shader program.
1436 link_gs_inout_layout_qualifiers(struct gl_shader_program
*prog
,
1437 struct gl_shader
*linked_shader
,
1438 struct gl_shader
**shader_list
,
1439 unsigned num_shaders
)
1441 linked_shader
->Geom
.VerticesOut
= 0;
1442 linked_shader
->Geom
.Invocations
= 0;
1443 linked_shader
->Geom
.InputType
= PRIM_UNKNOWN
;
1444 linked_shader
->Geom
.OutputType
= PRIM_UNKNOWN
;
1446 /* No in/out qualifiers defined for anything but GLSL 1.50+
1447 * geometry shaders so far.
1449 if (linked_shader
->Stage
!= MESA_SHADER_GEOMETRY
|| prog
->Version
< 150)
1452 /* From the GLSL 1.50 spec, page 46:
1454 * "All geometry shader output layout declarations in a program
1455 * must declare the same layout and same value for
1456 * max_vertices. There must be at least one geometry output
1457 * layout declaration somewhere in a program, but not all
1458 * geometry shaders (compilation units) are required to
1462 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1463 struct gl_shader
*shader
= shader_list
[i
];
1465 if (shader
->Geom
.InputType
!= PRIM_UNKNOWN
) {
1466 if (linked_shader
->Geom
.InputType
!= PRIM_UNKNOWN
&&
1467 linked_shader
->Geom
.InputType
!= shader
->Geom
.InputType
) {
1468 linker_error(prog
, "geometry shader defined with conflicting "
1472 linked_shader
->Geom
.InputType
= shader
->Geom
.InputType
;
1475 if (shader
->Geom
.OutputType
!= PRIM_UNKNOWN
) {
1476 if (linked_shader
->Geom
.OutputType
!= PRIM_UNKNOWN
&&
1477 linked_shader
->Geom
.OutputType
!= shader
->Geom
.OutputType
) {
1478 linker_error(prog
, "geometry shader defined with conflicting "
1482 linked_shader
->Geom
.OutputType
= shader
->Geom
.OutputType
;
1485 if (shader
->Geom
.VerticesOut
!= 0) {
1486 if (linked_shader
->Geom
.VerticesOut
!= 0 &&
1487 linked_shader
->Geom
.VerticesOut
!= shader
->Geom
.VerticesOut
) {
1488 linker_error(prog
, "geometry shader defined with conflicting "
1489 "output vertex count (%d and %d)\n",
1490 linked_shader
->Geom
.VerticesOut
,
1491 shader
->Geom
.VerticesOut
);
1494 linked_shader
->Geom
.VerticesOut
= shader
->Geom
.VerticesOut
;
1497 if (shader
->Geom
.Invocations
!= 0) {
1498 if (linked_shader
->Geom
.Invocations
!= 0 &&
1499 linked_shader
->Geom
.Invocations
!= shader
->Geom
.Invocations
) {
1500 linker_error(prog
, "geometry shader defined with conflicting "
1501 "invocation count (%d and %d)\n",
1502 linked_shader
->Geom
.Invocations
,
1503 shader
->Geom
.Invocations
);
1506 linked_shader
->Geom
.Invocations
= shader
->Geom
.Invocations
;
1510 /* Just do the intrastage -> interstage propagation right now,
1511 * since we already know we're in the right type of shader program
1514 if (linked_shader
->Geom
.InputType
== PRIM_UNKNOWN
) {
1516 "geometry shader didn't declare primitive input type\n");
1519 prog
->Geom
.InputType
= linked_shader
->Geom
.InputType
;
1521 if (linked_shader
->Geom
.OutputType
== PRIM_UNKNOWN
) {
1523 "geometry shader didn't declare primitive output type\n");
1526 prog
->Geom
.OutputType
= linked_shader
->Geom
.OutputType
;
1528 if (linked_shader
->Geom
.VerticesOut
== 0) {
1530 "geometry shader didn't declare max_vertices\n");
1533 prog
->Geom
.VerticesOut
= linked_shader
->Geom
.VerticesOut
;
1535 if (linked_shader
->Geom
.Invocations
== 0)
1536 linked_shader
->Geom
.Invocations
= 1;
1538 prog
->Geom
.Invocations
= linked_shader
->Geom
.Invocations
;
1543 * Perform cross-validation of compute shader local_size_{x,y,z} layout
1544 * qualifiers for the attached compute shaders, and propagate them to the
1545 * linked CS and linked shader program.
1548 link_cs_input_layout_qualifiers(struct gl_shader_program
*prog
,
1549 struct gl_shader
*linked_shader
,
1550 struct gl_shader
**shader_list
,
1551 unsigned num_shaders
)
1553 for (int i
= 0; i
< 3; i
++)
1554 linked_shader
->Comp
.LocalSize
[i
] = 0;
1556 /* This function is called for all shader stages, but it only has an effect
1557 * for compute shaders.
1559 if (linked_shader
->Stage
!= MESA_SHADER_COMPUTE
)
1562 /* From the ARB_compute_shader spec, in the section describing local size
1565 * If multiple compute shaders attached to a single program object
1566 * declare local work-group size, the declarations must be identical;
1567 * otherwise a link-time error results. Furthermore, if a program
1568 * object contains any compute shaders, at least one must contain an
1569 * input layout qualifier specifying the local work sizes of the
1570 * program, or a link-time error will occur.
1572 for (unsigned sh
= 0; sh
< num_shaders
; sh
++) {
1573 struct gl_shader
*shader
= shader_list
[sh
];
1575 if (shader
->Comp
.LocalSize
[0] != 0) {
1576 if (linked_shader
->Comp
.LocalSize
[0] != 0) {
1577 for (int i
= 0; i
< 3; i
++) {
1578 if (linked_shader
->Comp
.LocalSize
[i
] !=
1579 shader
->Comp
.LocalSize
[i
]) {
1580 linker_error(prog
, "compute shader defined with conflicting "
1586 for (int i
= 0; i
< 3; i
++)
1587 linked_shader
->Comp
.LocalSize
[i
] = shader
->Comp
.LocalSize
[i
];
1591 /* Just do the intrastage -> interstage propagation right now,
1592 * since we already know we're in the right type of shader program
1595 if (linked_shader
->Comp
.LocalSize
[0] == 0) {
1596 linker_error(prog
, "compute shader didn't declare local size\n");
1599 for (int i
= 0; i
< 3; i
++)
1600 prog
->Comp
.LocalSize
[i
] = linked_shader
->Comp
.LocalSize
[i
];
1605 * Combine a group of shaders for a single stage to generate a linked shader
1608 * If this function is supplied a single shader, it is cloned, and the new
1609 * shader is returned.
1611 static struct gl_shader
*
1612 link_intrastage_shaders(void *mem_ctx
,
1613 struct gl_context
*ctx
,
1614 struct gl_shader_program
*prog
,
1615 struct gl_shader
**shader_list
,
1616 unsigned num_shaders
)
1618 struct gl_uniform_block
*uniform_blocks
= NULL
;
1620 /* Check that global variables defined in multiple shaders are consistent.
1622 cross_validate_globals(prog
, shader_list
, num_shaders
, false);
1623 if (!prog
->LinkStatus
)
1626 /* Check that interface blocks defined in multiple shaders are consistent.
1628 validate_intrastage_interface_blocks(prog
, (const gl_shader
**)shader_list
,
1630 if (!prog
->LinkStatus
)
1633 /* Link up uniform blocks defined within this stage. */
1634 const unsigned num_uniform_blocks
=
1635 link_uniform_blocks(mem_ctx
, prog
, shader_list
, num_shaders
,
1637 if (!prog
->LinkStatus
)
1640 /* Check that there is only a single definition of each function signature
1641 * across all shaders.
1643 for (unsigned i
= 0; i
< (num_shaders
- 1); i
++) {
1644 foreach_in_list(ir_instruction
, node
, shader_list
[i
]->ir
) {
1645 ir_function
*const f
= node
->as_function();
1650 for (unsigned j
= i
+ 1; j
< num_shaders
; j
++) {
1651 ir_function
*const other
=
1652 shader_list
[j
]->symbols
->get_function(f
->name
);
1654 /* If the other shader has no function (and therefore no function
1655 * signatures) with the same name, skip to the next shader.
1660 foreach_in_list(ir_function_signature
, sig
, &f
->signatures
) {
1661 if (!sig
->is_defined
|| sig
->is_builtin())
1664 ir_function_signature
*other_sig
=
1665 other
->exact_matching_signature(NULL
, &sig
->parameters
);
1667 if ((other_sig
!= NULL
) && other_sig
->is_defined
1668 && !other_sig
->is_builtin()) {
1669 linker_error(prog
, "function `%s' is multiply defined\n",
1678 /* Find the shader that defines main, and make a clone of it.
1680 * Starting with the clone, search for undefined references. If one is
1681 * found, find the shader that defines it. Clone the reference and add
1682 * it to the shader. Repeat until there are no undefined references or
1683 * until a reference cannot be resolved.
1685 gl_shader
*main
= NULL
;
1686 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1687 if (link_get_main_function_signature(shader_list
[i
]) != NULL
) {
1688 main
= shader_list
[i
];
1694 linker_error(prog
, "%s shader lacks `main'\n",
1695 _mesa_shader_stage_to_string(shader_list
[0]->Stage
));
1699 gl_shader
*linked
= ctx
->Driver
.NewShader(NULL
, 0, main
->Type
);
1700 linked
->ir
= new(linked
) exec_list
;
1701 clone_ir_list(mem_ctx
, linked
->ir
, main
->ir
);
1703 linked
->UniformBlocks
= uniform_blocks
;
1704 linked
->NumUniformBlocks
= num_uniform_blocks
;
1705 ralloc_steal(linked
, linked
->UniformBlocks
);
1707 link_fs_input_layout_qualifiers(prog
, linked
, shader_list
, num_shaders
);
1708 link_gs_inout_layout_qualifiers(prog
, linked
, shader_list
, num_shaders
);
1709 link_cs_input_layout_qualifiers(prog
, linked
, shader_list
, num_shaders
);
1711 populate_symbol_table(linked
);
1713 /* The pointer to the main function in the final linked shader (i.e., the
1714 * copy of the original shader that contained the main function).
1716 ir_function_signature
*const main_sig
=
1717 link_get_main_function_signature(linked
);
1719 /* Move any instructions other than variable declarations or function
1720 * declarations into main.
1722 exec_node
*insertion_point
=
1723 move_non_declarations(linked
->ir
, (exec_node
*) &main_sig
->body
, false,
1726 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1727 if (shader_list
[i
] == main
)
1730 insertion_point
= move_non_declarations(shader_list
[i
]->ir
,
1731 insertion_point
, true, linked
);
1734 /* Check if any shader needs built-in functions. */
1735 bool need_builtins
= false;
1736 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1737 if (shader_list
[i
]->uses_builtin_functions
) {
1738 need_builtins
= true;
1744 if (need_builtins
) {
1745 /* Make a temporary array one larger than shader_list, which will hold
1746 * the built-in function shader as well.
1748 gl_shader
**linking_shaders
= (gl_shader
**)
1749 calloc(num_shaders
+ 1, sizeof(gl_shader
*));
1751 ok
= linking_shaders
!= NULL
;
1754 memcpy(linking_shaders
, shader_list
, num_shaders
* sizeof(gl_shader
*));
1755 linking_shaders
[num_shaders
] = _mesa_glsl_get_builtin_function_shader();
1757 ok
= link_function_calls(prog
, linked
, linking_shaders
, num_shaders
+ 1);
1759 free(linking_shaders
);
1761 _mesa_error_no_memory(__func__
);
1764 ok
= link_function_calls(prog
, linked
, shader_list
, num_shaders
);
1769 ctx
->Driver
.DeleteShader(ctx
, linked
);
1773 /* At this point linked should contain all of the linked IR, so
1774 * validate it to make sure nothing went wrong.
1776 validate_ir_tree(linked
->ir
);
1778 /* Set the size of geometry shader input arrays */
1779 if (linked
->Stage
== MESA_SHADER_GEOMETRY
) {
1780 unsigned num_vertices
= vertices_per_prim(prog
->Geom
.InputType
);
1781 geom_array_resize_visitor
input_resize_visitor(num_vertices
, prog
);
1782 foreach_in_list(ir_instruction
, ir
, linked
->ir
) {
1783 ir
->accept(&input_resize_visitor
);
1787 if (ctx
->Const
.VertexID_is_zero_based
)
1788 lower_vertex_id(linked
);
1790 /* Make a pass over all variable declarations to ensure that arrays with
1791 * unspecified sizes have a size specified. The size is inferred from the
1792 * max_array_access field.
1794 array_sizing_visitor v
;
1796 v
.fixup_unnamed_interface_types();
1802 * Update the sizes of linked shader uniform arrays to the maximum
1805 * From page 81 (page 95 of the PDF) of the OpenGL 2.1 spec:
1807 * If one or more elements of an array are active,
1808 * GetActiveUniform will return the name of the array in name,
1809 * subject to the restrictions listed above. The type of the array
1810 * is returned in type. The size parameter contains the highest
1811 * array element index used, plus one. The compiler or linker
1812 * determines the highest index used. There will be only one
1813 * active uniform reported by the GL per uniform array.
1817 update_array_sizes(struct gl_shader_program
*prog
)
1819 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
1820 if (prog
->_LinkedShaders
[i
] == NULL
)
1823 foreach_in_list(ir_instruction
, node
, prog
->_LinkedShaders
[i
]->ir
) {
1824 ir_variable
*const var
= node
->as_variable();
1826 if ((var
== NULL
) || (var
->data
.mode
!= ir_var_uniform
) ||
1827 !var
->type
->is_array())
1830 /* GL_ARB_uniform_buffer_object says that std140 uniforms
1831 * will not be eliminated. Since we always do std140, just
1832 * don't resize arrays in UBOs.
1834 * Atomic counters are supposed to get deterministic
1835 * locations assigned based on the declaration ordering and
1836 * sizes, array compaction would mess that up.
1838 if (var
->is_in_uniform_block() || var
->type
->contains_atomic())
1841 unsigned int size
= var
->data
.max_array_access
;
1842 for (unsigned j
= 0; j
< MESA_SHADER_STAGES
; j
++) {
1843 if (prog
->_LinkedShaders
[j
] == NULL
)
1846 foreach_in_list(ir_instruction
, node2
, prog
->_LinkedShaders
[j
]->ir
) {
1847 ir_variable
*other_var
= node2
->as_variable();
1851 if (strcmp(var
->name
, other_var
->name
) == 0 &&
1852 other_var
->data
.max_array_access
> size
) {
1853 size
= other_var
->data
.max_array_access
;
1858 if (size
+ 1 != var
->type
->length
) {
1859 /* If this is a built-in uniform (i.e., it's backed by some
1860 * fixed-function state), adjust the number of state slots to
1861 * match the new array size. The number of slots per array entry
1862 * is not known. It seems safe to assume that the total number of
1863 * slots is an integer multiple of the number of array elements.
1864 * Determine the number of slots per array element by dividing by
1865 * the old (total) size.
1867 const unsigned num_slots
= var
->get_num_state_slots();
1868 if (num_slots
> 0) {
1869 var
->set_num_state_slots((size
+ 1)
1870 * (num_slots
/ var
->type
->length
));
1873 var
->type
= glsl_type::get_array_instance(var
->type
->fields
.array
,
1875 /* FINISHME: We should update the types of array
1876 * dereferences of this variable now.
1884 * Find a contiguous set of available bits in a bitmask.
1886 * \param used_mask Bits representing used (1) and unused (0) locations
1887 * \param needed_count Number of contiguous bits needed.
1890 * Base location of the available bits on success or -1 on failure.
1893 find_available_slots(unsigned used_mask
, unsigned needed_count
)
1895 unsigned needed_mask
= (1 << needed_count
) - 1;
1896 const int max_bit_to_test
= (8 * sizeof(used_mask
)) - needed_count
;
1898 /* The comparison to 32 is redundant, but without it GCC emits "warning:
1899 * cannot optimize possibly infinite loops" for the loop below.
1901 if ((needed_count
== 0) || (max_bit_to_test
< 0) || (max_bit_to_test
> 32))
1904 for (int i
= 0; i
<= max_bit_to_test
; i
++) {
1905 if ((needed_mask
& ~used_mask
) == needed_mask
)
1916 * Assign locations for either VS inputs or FS outputs
1918 * \param prog Shader program whose variables need locations assigned
1919 * \param target_index Selector for the program target to receive location
1920 * assignmnets. Must be either \c MESA_SHADER_VERTEX or
1921 * \c MESA_SHADER_FRAGMENT.
1922 * \param max_index Maximum number of generic locations. This corresponds
1923 * to either the maximum number of draw buffers or the
1924 * maximum number of generic attributes.
1927 * If locations are successfully assigned, true is returned. Otherwise an
1928 * error is emitted to the shader link log and false is returned.
1931 assign_attribute_or_color_locations(gl_shader_program
*prog
,
1932 unsigned target_index
,
1935 /* Mark invalid locations as being used.
1937 unsigned used_locations
= (max_index
>= 32)
1938 ? ~0 : ~((1 << max_index
) - 1);
1940 assert((target_index
== MESA_SHADER_VERTEX
)
1941 || (target_index
== MESA_SHADER_FRAGMENT
));
1943 gl_shader
*const sh
= prog
->_LinkedShaders
[target_index
];
1947 /* Operate in a total of four passes.
1949 * 1. Invalidate the location assignments for all vertex shader inputs.
1951 * 2. Assign locations for inputs that have user-defined (via
1952 * glBindVertexAttribLocation) locations and outputs that have
1953 * user-defined locations (via glBindFragDataLocation).
1955 * 3. Sort the attributes without assigned locations by number of slots
1956 * required in decreasing order. Fragmentation caused by attribute
1957 * locations assigned by the application may prevent large attributes
1958 * from having enough contiguous space.
1960 * 4. Assign locations to any inputs without assigned locations.
1963 const int generic_base
= (target_index
== MESA_SHADER_VERTEX
)
1964 ? (int) VERT_ATTRIB_GENERIC0
: (int) FRAG_RESULT_DATA0
;
1966 const enum ir_variable_mode direction
=
1967 (target_index
== MESA_SHADER_VERTEX
)
1968 ? ir_var_shader_in
: ir_var_shader_out
;
1971 /* Temporary storage for the set of attributes that need locations assigned.
1977 /* Used below in the call to qsort. */
1978 static int compare(const void *a
, const void *b
)
1980 const temp_attr
*const l
= (const temp_attr
*) a
;
1981 const temp_attr
*const r
= (const temp_attr
*) b
;
1983 /* Reversed because we want a descending order sort below. */
1984 return r
->slots
- l
->slots
;
1988 unsigned num_attr
= 0;
1990 foreach_in_list(ir_instruction
, node
, sh
->ir
) {
1991 ir_variable
*const var
= node
->as_variable();
1993 if ((var
== NULL
) || (var
->data
.mode
!= (unsigned) direction
))
1996 if (var
->data
.explicit_location
) {
1997 if ((var
->data
.location
>= (int)(max_index
+ generic_base
))
1998 || (var
->data
.location
< 0)) {
2000 "invalid explicit location %d specified for `%s'\n",
2001 (var
->data
.location
< 0)
2002 ? var
->data
.location
2003 : var
->data
.location
- generic_base
,
2007 } else if (target_index
== MESA_SHADER_VERTEX
) {
2010 if (prog
->AttributeBindings
->get(binding
, var
->name
)) {
2011 assert(binding
>= VERT_ATTRIB_GENERIC0
);
2012 var
->data
.location
= binding
;
2013 var
->data
.is_unmatched_generic_inout
= 0;
2015 } else if (target_index
== MESA_SHADER_FRAGMENT
) {
2019 if (prog
->FragDataBindings
->get(binding
, var
->name
)) {
2020 assert(binding
>= FRAG_RESULT_DATA0
);
2021 var
->data
.location
= binding
;
2022 var
->data
.is_unmatched_generic_inout
= 0;
2024 if (prog
->FragDataIndexBindings
->get(index
, var
->name
)) {
2025 var
->data
.index
= index
;
2030 /* If the variable is not a built-in and has a location statically
2031 * assigned in the shader (presumably via a layout qualifier), make sure
2032 * that it doesn't collide with other assigned locations. Otherwise,
2033 * add it to the list of variables that need linker-assigned locations.
2035 const unsigned slots
= var
->type
->count_attribute_slots();
2036 if (var
->data
.location
!= -1) {
2037 if (var
->data
.location
>= generic_base
&& var
->data
.index
< 1) {
2038 /* From page 61 of the OpenGL 4.0 spec:
2040 * "LinkProgram will fail if the attribute bindings assigned
2041 * by BindAttribLocation do not leave not enough space to
2042 * assign a location for an active matrix attribute or an
2043 * active attribute array, both of which require multiple
2044 * contiguous generic attributes."
2046 * I think above text prohibits the aliasing of explicit and
2047 * automatic assignments. But, aliasing is allowed in manual
2048 * assignments of attribute locations. See below comments for
2051 * From OpenGL 4.0 spec, page 61:
2053 * "It is possible for an application to bind more than one
2054 * attribute name to the same location. This is referred to as
2055 * aliasing. This will only work if only one of the aliased
2056 * attributes is active in the executable program, or if no
2057 * path through the shader consumes more than one attribute of
2058 * a set of attributes aliased to the same location. A link
2059 * error can occur if the linker determines that every path
2060 * through the shader consumes multiple aliased attributes,
2061 * but implementations are not required to generate an error
2064 * From GLSL 4.30 spec, page 54:
2066 * "A program will fail to link if any two non-vertex shader
2067 * input variables are assigned to the same location. For
2068 * vertex shaders, multiple input variables may be assigned
2069 * to the same location using either layout qualifiers or via
2070 * the OpenGL API. However, such aliasing is intended only to
2071 * support vertex shaders where each execution path accesses
2072 * at most one input per each location. Implementations are
2073 * permitted, but not required, to generate link-time errors
2074 * if they detect that every path through the vertex shader
2075 * executable accesses multiple inputs assigned to any single
2076 * location. For all shader types, a program will fail to link
2077 * if explicit location assignments leave the linker unable
2078 * to find space for other variables without explicit
2081 * From OpenGL ES 3.0 spec, page 56:
2083 * "Binding more than one attribute name to the same location
2084 * is referred to as aliasing, and is not permitted in OpenGL
2085 * ES Shading Language 3.00 vertex shaders. LinkProgram will
2086 * fail when this condition exists. However, aliasing is
2087 * possible in OpenGL ES Shading Language 1.00 vertex shaders.
2088 * This will only work if only one of the aliased attributes
2089 * is active in the executable program, or if no path through
2090 * the shader consumes more than one attribute of a set of
2091 * attributes aliased to the same location. A link error can
2092 * occur if the linker determines that every path through the
2093 * shader consumes multiple aliased attributes, but implemen-
2094 * tations are not required to generate an error in this case."
2096 * After looking at above references from OpenGL, OpenGL ES and
2097 * GLSL specifications, we allow aliasing of vertex input variables
2098 * in: OpenGL 2.0 (and above) and OpenGL ES 2.0.
2100 * NOTE: This is not required by the spec but its worth mentioning
2101 * here that we're not doing anything to make sure that no path
2102 * through the vertex shader executable accesses multiple inputs
2103 * assigned to any single location.
2106 /* Mask representing the contiguous slots that will be used by
2109 const unsigned attr
= var
->data
.location
- generic_base
;
2110 const unsigned use_mask
= (1 << slots
) - 1;
2111 const char *const string
= (target_index
== MESA_SHADER_VERTEX
)
2112 ? "vertex shader input" : "fragment shader output";
2114 /* Generate a link error if the requested locations for this
2115 * attribute exceed the maximum allowed attribute location.
2117 if (attr
+ slots
> max_index
) {
2119 "insufficient contiguous locations "
2120 "available for %s `%s' %d %d %d\n", string
,
2121 var
->name
, used_locations
, use_mask
, attr
);
2125 /* Generate a link error if the set of bits requested for this
2126 * attribute overlaps any previously allocated bits.
2128 if ((~(use_mask
<< attr
) & used_locations
) != used_locations
) {
2129 if (target_index
== MESA_SHADER_FRAGMENT
||
2130 (prog
->IsES
&& prog
->Version
>= 300)) {
2132 "overlapping location is assigned "
2133 "to %s `%s' %d %d %d\n", string
,
2134 var
->name
, used_locations
, use_mask
, attr
);
2137 linker_warning(prog
,
2138 "overlapping location is assigned "
2139 "to %s `%s' %d %d %d\n", string
,
2140 var
->name
, used_locations
, use_mask
, attr
);
2144 used_locations
|= (use_mask
<< attr
);
2150 to_assign
[num_attr
].slots
= slots
;
2151 to_assign
[num_attr
].var
= var
;
2155 /* If all of the attributes were assigned locations by the application (or
2156 * are built-in attributes with fixed locations), return early. This should
2157 * be the common case.
2162 qsort(to_assign
, num_attr
, sizeof(to_assign
[0]), temp_attr::compare
);
2164 if (target_index
== MESA_SHADER_VERTEX
) {
2165 /* VERT_ATTRIB_GENERIC0 is a pseudo-alias for VERT_ATTRIB_POS. It can
2166 * only be explicitly assigned by via glBindAttribLocation. Mark it as
2167 * reserved to prevent it from being automatically allocated below.
2169 find_deref_visitor
find("gl_Vertex");
2171 if (find
.variable_found())
2172 used_locations
|= (1 << 0);
2175 for (unsigned i
= 0; i
< num_attr
; i
++) {
2176 /* Mask representing the contiguous slots that will be used by this
2179 const unsigned use_mask
= (1 << to_assign
[i
].slots
) - 1;
2181 int location
= find_available_slots(used_locations
, to_assign
[i
].slots
);
2184 const char *const string
= (target_index
== MESA_SHADER_VERTEX
)
2185 ? "vertex shader input" : "fragment shader output";
2188 "insufficient contiguous locations "
2189 "available for %s `%s'\n",
2190 string
, to_assign
[i
].var
->name
);
2194 to_assign
[i
].var
->data
.location
= generic_base
+ location
;
2195 to_assign
[i
].var
->data
.is_unmatched_generic_inout
= 0;
2196 used_locations
|= (use_mask
<< location
);
2204 * Demote shader inputs and outputs that are not used in other stages
2207 demote_shader_inputs_and_outputs(gl_shader
*sh
, enum ir_variable_mode mode
)
2209 foreach_in_list(ir_instruction
, node
, sh
->ir
) {
2210 ir_variable
*const var
= node
->as_variable();
2212 if ((var
== NULL
) || (var
->data
.mode
!= int(mode
)))
2215 /* A shader 'in' or 'out' variable is only really an input or output if
2216 * its value is used by other shader stages. This will cause the variable
2217 * to have a location assigned.
2219 if (var
->data
.is_unmatched_generic_inout
) {
2220 assert(var
->data
.mode
!= ir_var_temporary
);
2221 var
->data
.mode
= ir_var_auto
;
2228 * Store the gl_FragDepth layout in the gl_shader_program struct.
2231 store_fragdepth_layout(struct gl_shader_program
*prog
)
2233 if (prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
] == NULL
) {
2237 struct exec_list
*ir
= prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
]->ir
;
2239 /* We don't look up the gl_FragDepth symbol directly because if
2240 * gl_FragDepth is not used in the shader, it's removed from the IR.
2241 * However, the symbol won't be removed from the symbol table.
2243 * We're only interested in the cases where the variable is NOT removed
2246 foreach_in_list(ir_instruction
, node
, ir
) {
2247 ir_variable
*const var
= node
->as_variable();
2249 if (var
== NULL
|| var
->data
.mode
!= ir_var_shader_out
) {
2253 if (strcmp(var
->name
, "gl_FragDepth") == 0) {
2254 switch (var
->data
.depth_layout
) {
2255 case ir_depth_layout_none
:
2256 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_NONE
;
2258 case ir_depth_layout_any
:
2259 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_ANY
;
2261 case ir_depth_layout_greater
:
2262 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_GREATER
;
2264 case ir_depth_layout_less
:
2265 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_LESS
;
2267 case ir_depth_layout_unchanged
:
2268 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_UNCHANGED
;
2279 * Validate the resources used by a program versus the implementation limits
2282 check_resources(struct gl_context
*ctx
, struct gl_shader_program
*prog
)
2284 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2285 struct gl_shader
*sh
= prog
->_LinkedShaders
[i
];
2290 if (sh
->num_samplers
> ctx
->Const
.Program
[i
].MaxTextureImageUnits
) {
2291 linker_error(prog
, "Too many %s shader texture samplers\n",
2292 _mesa_shader_stage_to_string(i
));
2295 if (sh
->num_uniform_components
>
2296 ctx
->Const
.Program
[i
].MaxUniformComponents
) {
2297 if (ctx
->Const
.GLSLSkipStrictMaxUniformLimitCheck
) {
2298 linker_warning(prog
, "Too many %s shader default uniform block "
2299 "components, but the driver will try to optimize "
2300 "them out; this is non-portable out-of-spec "
2302 _mesa_shader_stage_to_string(i
));
2304 linker_error(prog
, "Too many %s shader default uniform block "
2306 _mesa_shader_stage_to_string(i
));
2310 if (sh
->num_combined_uniform_components
>
2311 ctx
->Const
.Program
[i
].MaxCombinedUniformComponents
) {
2312 if (ctx
->Const
.GLSLSkipStrictMaxUniformLimitCheck
) {
2313 linker_warning(prog
, "Too many %s shader uniform components, "
2314 "but the driver will try to optimize them out; "
2315 "this is non-portable out-of-spec behavior\n",
2316 _mesa_shader_stage_to_string(i
));
2318 linker_error(prog
, "Too many %s shader uniform components\n",
2319 _mesa_shader_stage_to_string(i
));
2324 unsigned blocks
[MESA_SHADER_STAGES
] = {0};
2325 unsigned total_uniform_blocks
= 0;
2327 for (unsigned i
= 0; i
< prog
->NumUniformBlocks
; i
++) {
2328 for (unsigned j
= 0; j
< MESA_SHADER_STAGES
; j
++) {
2329 if (prog
->UniformBlockStageIndex
[j
][i
] != -1) {
2331 total_uniform_blocks
++;
2335 if (total_uniform_blocks
> ctx
->Const
.MaxCombinedUniformBlocks
) {
2336 linker_error(prog
, "Too many combined uniform blocks (%d/%d)\n",
2337 prog
->NumUniformBlocks
,
2338 ctx
->Const
.MaxCombinedUniformBlocks
);
2340 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2341 const unsigned max_uniform_blocks
=
2342 ctx
->Const
.Program
[i
].MaxUniformBlocks
;
2343 if (blocks
[i
] > max_uniform_blocks
) {
2344 linker_error(prog
, "Too many %s uniform blocks (%d/%d)\n",
2345 _mesa_shader_stage_to_string(i
),
2347 max_uniform_blocks
);
2356 * Validate shader image resources.
2359 check_image_resources(struct gl_context
*ctx
, struct gl_shader_program
*prog
)
2361 unsigned total_image_units
= 0;
2362 unsigned fragment_outputs
= 0;
2364 if (!ctx
->Extensions
.ARB_shader_image_load_store
)
2367 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2368 struct gl_shader
*sh
= prog
->_LinkedShaders
[i
];
2371 if (sh
->NumImages
> ctx
->Const
.Program
[i
].MaxImageUniforms
)
2372 linker_error(prog
, "Too many %s shader image uniforms\n",
2373 _mesa_shader_stage_to_string(i
));
2375 total_image_units
+= sh
->NumImages
;
2377 if (i
== MESA_SHADER_FRAGMENT
) {
2378 foreach_in_list(ir_instruction
, node
, sh
->ir
) {
2379 ir_variable
*var
= node
->as_variable();
2380 if (var
&& var
->data
.mode
== ir_var_shader_out
)
2381 fragment_outputs
+= var
->type
->count_attribute_slots();
2387 if (total_image_units
> ctx
->Const
.MaxCombinedImageUniforms
)
2388 linker_error(prog
, "Too many combined image uniforms\n");
2390 if (total_image_units
+ fragment_outputs
>
2391 ctx
->Const
.MaxCombinedImageUnitsAndFragmentOutputs
)
2392 linker_error(prog
, "Too many combined image uniforms and fragment outputs\n");
2397 * Initializes explicit location slots to INACTIVE_UNIFORM_EXPLICIT_LOCATION
2398 * for a variable, checks for overlaps between other uniforms using explicit
2402 reserve_explicit_locations(struct gl_shader_program
*prog
,
2403 string_to_uint_map
*map
, ir_variable
*var
)
2405 unsigned slots
= var
->type
->uniform_locations();
2406 unsigned max_loc
= var
->data
.location
+ slots
- 1;
2408 /* Resize remap table if locations do not fit in the current one. */
2409 if (max_loc
+ 1 > prog
->NumUniformRemapTable
) {
2410 prog
->UniformRemapTable
=
2411 reralloc(prog
, prog
->UniformRemapTable
,
2412 gl_uniform_storage
*,
2415 if (!prog
->UniformRemapTable
) {
2416 linker_error(prog
, "Out of memory during linking.\n");
2420 /* Initialize allocated space. */
2421 for (unsigned i
= prog
->NumUniformRemapTable
; i
< max_loc
+ 1; i
++)
2422 prog
->UniformRemapTable
[i
] = NULL
;
2424 prog
->NumUniformRemapTable
= max_loc
+ 1;
2427 for (unsigned i
= 0; i
< slots
; i
++) {
2428 unsigned loc
= var
->data
.location
+ i
;
2430 /* Check if location is already used. */
2431 if (prog
->UniformRemapTable
[loc
] == INACTIVE_UNIFORM_EXPLICIT_LOCATION
) {
2433 /* Possibly same uniform from a different stage, this is ok. */
2435 if (map
->get(hash_loc
, var
->name
) && hash_loc
== loc
- i
)
2438 /* ARB_explicit_uniform_location specification states:
2440 * "No two default-block uniform variables in the program can have
2441 * the same location, even if they are unused, otherwise a compiler
2442 * or linker error will be generated."
2445 "location qualifier for uniform %s overlaps "
2446 "previously used location\n",
2451 /* Initialize location as inactive before optimization
2452 * rounds and location assignment.
2454 prog
->UniformRemapTable
[loc
] = INACTIVE_UNIFORM_EXPLICIT_LOCATION
;
2457 /* Note, base location used for arrays. */
2458 map
->put(var
->data
.location
, var
->name
);
2464 * Check and reserve all explicit uniform locations, called before
2465 * any optimizations happen to handle also inactive uniforms and
2466 * inactive array elements that may get trimmed away.
2469 check_explicit_uniform_locations(struct gl_context
*ctx
,
2470 struct gl_shader_program
*prog
)
2472 if (!ctx
->Extensions
.ARB_explicit_uniform_location
)
2475 /* This map is used to detect if overlapping explicit locations
2476 * occur with the same uniform (from different stage) or a different one.
2478 string_to_uint_map
*uniform_map
= new string_to_uint_map
;
2481 linker_error(prog
, "Out of memory during linking.\n");
2485 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2486 struct gl_shader
*sh
= prog
->_LinkedShaders
[i
];
2491 foreach_in_list(ir_instruction
, node
, sh
->ir
) {
2492 ir_variable
*var
= node
->as_variable();
2493 if ((var
&& var
->data
.mode
== ir_var_uniform
) &&
2494 var
->data
.explicit_location
) {
2495 if (!reserve_explicit_locations(prog
, uniform_map
, var
)) {
2507 link_shaders(struct gl_context
*ctx
, struct gl_shader_program
*prog
)
2509 tfeedback_decl
*tfeedback_decls
= NULL
;
2510 unsigned num_tfeedback_decls
= prog
->TransformFeedback
.NumVarying
;
2512 void *mem_ctx
= ralloc_context(NULL
); // temporary linker context
2514 prog
->LinkStatus
= true; /* All error paths will set this to false */
2515 prog
->Validated
= false;
2516 prog
->_Used
= false;
2518 prog
->ARB_fragment_coord_conventions_enable
= false;
2520 /* Separate the shaders into groups based on their type.
2522 struct gl_shader
**shader_list
[MESA_SHADER_STAGES
];
2523 unsigned num_shaders
[MESA_SHADER_STAGES
];
2525 for (int i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2526 shader_list
[i
] = (struct gl_shader
**)
2527 calloc(prog
->NumShaders
, sizeof(struct gl_shader
*));
2531 unsigned min_version
= UINT_MAX
;
2532 unsigned max_version
= 0;
2533 const bool is_es_prog
=
2534 (prog
->NumShaders
> 0 && prog
->Shaders
[0]->IsES
) ? true : false;
2535 for (unsigned i
= 0; i
< prog
->NumShaders
; i
++) {
2536 min_version
= MIN2(min_version
, prog
->Shaders
[i
]->Version
);
2537 max_version
= MAX2(max_version
, prog
->Shaders
[i
]->Version
);
2539 if (prog
->Shaders
[i
]->IsES
!= is_es_prog
) {
2540 linker_error(prog
, "all shaders must use same shading "
2541 "language version\n");
2545 if (prog
->Shaders
[i
]->ARB_fragment_coord_conventions_enable
) {
2546 prog
->ARB_fragment_coord_conventions_enable
= true;
2549 gl_shader_stage shader_type
= prog
->Shaders
[i
]->Stage
;
2550 shader_list
[shader_type
][num_shaders
[shader_type
]] = prog
->Shaders
[i
];
2551 num_shaders
[shader_type
]++;
2554 /* In desktop GLSL, different shader versions may be linked together. In
2555 * GLSL ES, all shader versions must be the same.
2557 if (is_es_prog
&& min_version
!= max_version
) {
2558 linker_error(prog
, "all shaders must use same shading "
2559 "language version\n");
2563 prog
->Version
= max_version
;
2564 prog
->IsES
= is_es_prog
;
2566 /* Geometry shaders have to be linked with vertex shaders.
2568 if (num_shaders
[MESA_SHADER_GEOMETRY
] > 0 &&
2569 num_shaders
[MESA_SHADER_VERTEX
] == 0 &&
2570 !prog
->SeparateShader
) {
2571 linker_error(prog
, "Geometry shader must be linked with "
2576 /* Compute shaders have additional restrictions. */
2577 if (num_shaders
[MESA_SHADER_COMPUTE
] > 0 &&
2578 num_shaders
[MESA_SHADER_COMPUTE
] != prog
->NumShaders
) {
2579 linker_error(prog
, "Compute shaders may not be linked with any other "
2580 "type of shader\n");
2583 for (unsigned int i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2584 if (prog
->_LinkedShaders
[i
] != NULL
)
2585 ctx
->Driver
.DeleteShader(ctx
, prog
->_LinkedShaders
[i
]);
2587 prog
->_LinkedShaders
[i
] = NULL
;
2590 /* Link all shaders for a particular stage and validate the result.
2592 for (int stage
= 0; stage
< MESA_SHADER_STAGES
; stage
++) {
2593 if (num_shaders
[stage
] > 0) {
2594 gl_shader
*const sh
=
2595 link_intrastage_shaders(mem_ctx
, ctx
, prog
, shader_list
[stage
],
2596 num_shaders
[stage
]);
2598 if (!prog
->LinkStatus
)
2602 case MESA_SHADER_VERTEX
:
2603 validate_vertex_shader_executable(prog
, sh
);
2605 case MESA_SHADER_GEOMETRY
:
2606 validate_geometry_shader_executable(prog
, sh
);
2608 case MESA_SHADER_FRAGMENT
:
2609 validate_fragment_shader_executable(prog
, sh
);
2612 if (!prog
->LinkStatus
)
2615 _mesa_reference_shader(ctx
, &prog
->_LinkedShaders
[stage
], sh
);
2619 if (num_shaders
[MESA_SHADER_GEOMETRY
] > 0)
2620 prog
->LastClipDistanceArraySize
= prog
->Geom
.ClipDistanceArraySize
;
2621 else if (num_shaders
[MESA_SHADER_VERTEX
] > 0)
2622 prog
->LastClipDistanceArraySize
= prog
->Vert
.ClipDistanceArraySize
;
2624 prog
->LastClipDistanceArraySize
= 0; /* Not used */
2626 /* Here begins the inter-stage linking phase. Some initial validation is
2627 * performed, then locations are assigned for uniforms, attributes, and
2630 cross_validate_uniforms(prog
);
2631 if (!prog
->LinkStatus
)
2636 for (prev
= 0; prev
<= MESA_SHADER_FRAGMENT
; prev
++) {
2637 if (prog
->_LinkedShaders
[prev
] != NULL
)
2641 check_explicit_uniform_locations(ctx
, prog
);
2642 if (!prog
->LinkStatus
)
2645 /* Validate the inputs of each stage with the output of the preceding
2648 for (unsigned i
= prev
+ 1; i
<= MESA_SHADER_FRAGMENT
; i
++) {
2649 if (prog
->_LinkedShaders
[i
] == NULL
)
2652 validate_interstage_inout_blocks(prog
, prog
->_LinkedShaders
[prev
],
2653 prog
->_LinkedShaders
[i
]);
2654 if (!prog
->LinkStatus
)
2657 cross_validate_outputs_to_inputs(prog
,
2658 prog
->_LinkedShaders
[prev
],
2659 prog
->_LinkedShaders
[i
]);
2660 if (!prog
->LinkStatus
)
2666 /* Cross-validate uniform blocks between shader stages */
2667 validate_interstage_uniform_blocks(prog
, prog
->_LinkedShaders
,
2668 MESA_SHADER_STAGES
);
2669 if (!prog
->LinkStatus
)
2672 for (unsigned int i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2673 if (prog
->_LinkedShaders
[i
] != NULL
)
2674 lower_named_interface_blocks(mem_ctx
, prog
->_LinkedShaders
[i
]);
2677 /* Implement the GLSL 1.30+ rule for discard vs infinite loops Do
2678 * it before optimization because we want most of the checks to get
2679 * dropped thanks to constant propagation.
2681 * This rule also applies to GLSL ES 3.00.
2683 if (max_version
>= (is_es_prog
? 300 : 130)) {
2684 struct gl_shader
*sh
= prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
];
2686 lower_discard_flow(sh
->ir
);
2690 if (!interstage_cross_validate_uniform_blocks(prog
))
2693 /* Do common optimization before assigning storage for attributes,
2694 * uniforms, and varyings. Later optimization could possibly make
2695 * some of that unused.
2697 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2698 if (prog
->_LinkedShaders
[i
] == NULL
)
2701 detect_recursion_linked(prog
, prog
->_LinkedShaders
[i
]->ir
);
2702 if (!prog
->LinkStatus
)
2705 if (ctx
->Const
.ShaderCompilerOptions
[i
].LowerClipDistance
) {
2706 lower_clip_distance(prog
->_LinkedShaders
[i
]);
2709 while (do_common_optimization(prog
->_LinkedShaders
[i
]->ir
, true, false,
2710 &ctx
->Const
.ShaderCompilerOptions
[i
],
2711 ctx
->Const
.NativeIntegers
))
2714 lower_const_arrays_to_uniforms(prog
->_LinkedShaders
[i
]->ir
);
2717 /* Check and validate stream emissions in geometry shaders */
2718 validate_geometry_shader_emissions(ctx
, prog
);
2720 /* Mark all generic shader inputs and outputs as unpaired. */
2721 for (unsigned i
= MESA_SHADER_VERTEX
; i
<= MESA_SHADER_FRAGMENT
; i
++) {
2722 if (prog
->_LinkedShaders
[i
] != NULL
) {
2723 link_invalidate_variable_locations(prog
->_LinkedShaders
[i
]->ir
);
2727 /* FINISHME: The value of the max_attribute_index parameter is
2728 * FINISHME: implementation dependent based on the value of
2729 * FINISHME: GL_MAX_VERTEX_ATTRIBS. GL_MAX_VERTEX_ATTRIBS must be
2730 * FINISHME: at least 16, so hardcode 16 for now.
2732 if (!assign_attribute_or_color_locations(prog
, MESA_SHADER_VERTEX
, 16)) {
2736 if (!assign_attribute_or_color_locations(prog
, MESA_SHADER_FRAGMENT
, MAX2(ctx
->Const
.MaxDrawBuffers
, ctx
->Const
.MaxDualSourceDrawBuffers
))) {
2741 for (first
= 0; first
<= MESA_SHADER_FRAGMENT
; first
++) {
2742 if (prog
->_LinkedShaders
[first
] != NULL
)
2746 if (num_tfeedback_decls
!= 0) {
2747 /* From GL_EXT_transform_feedback:
2748 * A program will fail to link if:
2750 * * the <count> specified by TransformFeedbackVaryingsEXT is
2751 * non-zero, but the program object has no vertex or geometry
2754 if (first
== MESA_SHADER_FRAGMENT
) {
2755 linker_error(prog
, "Transform feedback varyings specified, but "
2756 "no vertex or geometry shader is present.\n");
2760 tfeedback_decls
= ralloc_array(mem_ctx
, tfeedback_decl
,
2761 prog
->TransformFeedback
.NumVarying
);
2762 if (!parse_tfeedback_decls(ctx
, prog
, mem_ctx
, num_tfeedback_decls
,
2763 prog
->TransformFeedback
.VaryingNames
,
2768 /* Linking the stages in the opposite order (from fragment to vertex)
2769 * ensures that inter-shader outputs written to in an earlier stage are
2770 * eliminated if they are (transitively) not used in a later stage.
2773 for (last
= MESA_SHADER_FRAGMENT
; last
>= 0; last
--) {
2774 if (prog
->_LinkedShaders
[last
] != NULL
)
2778 if (last
>= 0 && last
< MESA_SHADER_FRAGMENT
) {
2779 gl_shader
*const sh
= prog
->_LinkedShaders
[last
];
2781 if (first
== MESA_SHADER_GEOMETRY
) {
2782 /* There was no vertex shader, but we still have to assign varying
2783 * locations for use by geometry shader inputs in SSO.
2785 * If the shader is not separable (i.e., prog->SeparateShader is
2786 * false), linking will have already failed when first is
2787 * MESA_SHADER_GEOMETRY.
2789 if (!assign_varying_locations(ctx
, mem_ctx
, prog
,
2791 num_tfeedback_decls
, tfeedback_decls
,
2792 prog
->Geom
.VerticesIn
))
2796 if (num_tfeedback_decls
!= 0 || prog
->SeparateShader
) {
2797 /* There was no fragment shader, but we still have to assign varying
2798 * locations for use by transform feedback.
2800 if (!assign_varying_locations(ctx
, mem_ctx
, prog
,
2802 num_tfeedback_decls
, tfeedback_decls
,
2807 do_dead_builtin_varyings(ctx
, sh
, NULL
,
2808 num_tfeedback_decls
, tfeedback_decls
);
2810 if (!prog
->SeparateShader
)
2811 demote_shader_inputs_and_outputs(sh
, ir_var_shader_out
);
2813 /* Eliminate code that is now dead due to unused outputs being demoted.
2815 while (do_dead_code(sh
->ir
, false))
2818 else if (first
== MESA_SHADER_FRAGMENT
) {
2819 /* If the program only contains a fragment shader...
2821 gl_shader
*const sh
= prog
->_LinkedShaders
[first
];
2823 do_dead_builtin_varyings(ctx
, NULL
, sh
,
2824 num_tfeedback_decls
, tfeedback_decls
);
2826 if (prog
->SeparateShader
) {
2827 if (!assign_varying_locations(ctx
, mem_ctx
, prog
,
2828 NULL
/* producer */,
2830 0 /* num_tfeedback_decls */,
2831 NULL
/* tfeedback_decls */,
2832 0 /* gs_input_vertices */))
2835 demote_shader_inputs_and_outputs(sh
, ir_var_shader_in
);
2837 while (do_dead_code(sh
->ir
, false))
2842 for (int i
= next
- 1; i
>= 0; i
--) {
2843 if (prog
->_LinkedShaders
[i
] == NULL
)
2846 gl_shader
*const sh_i
= prog
->_LinkedShaders
[i
];
2847 gl_shader
*const sh_next
= prog
->_LinkedShaders
[next
];
2848 unsigned gs_input_vertices
=
2849 next
== MESA_SHADER_GEOMETRY
? prog
->Geom
.VerticesIn
: 0;
2851 if (!assign_varying_locations(ctx
, mem_ctx
, prog
, sh_i
, sh_next
,
2852 next
== MESA_SHADER_FRAGMENT
? num_tfeedback_decls
: 0,
2853 tfeedback_decls
, gs_input_vertices
))
2856 do_dead_builtin_varyings(ctx
, sh_i
, sh_next
,
2857 next
== MESA_SHADER_FRAGMENT
? num_tfeedback_decls
: 0,
2860 demote_shader_inputs_and_outputs(sh_i
, ir_var_shader_out
);
2861 demote_shader_inputs_and_outputs(sh_next
, ir_var_shader_in
);
2863 /* Eliminate code that is now dead due to unused outputs being demoted.
2865 while (do_dead_code(sh_i
->ir
, false))
2867 while (do_dead_code(sh_next
->ir
, false))
2870 /* This must be done after all dead varyings are eliminated. */
2871 if (!check_against_output_limit(ctx
, prog
, sh_i
))
2873 if (!check_against_input_limit(ctx
, prog
, sh_next
))
2879 if (!store_tfeedback_info(ctx
, prog
, num_tfeedback_decls
, tfeedback_decls
))
2882 update_array_sizes(prog
);
2883 link_assign_uniform_locations(prog
, ctx
->Const
.UniformBooleanTrue
);
2884 link_assign_atomic_counter_resources(ctx
, prog
);
2885 store_fragdepth_layout(prog
);
2887 check_resources(ctx
, prog
);
2888 check_image_resources(ctx
, prog
);
2889 link_check_atomic_counter_resources(ctx
, prog
);
2891 if (!prog
->LinkStatus
)
2894 /* OpenGL ES requires that a vertex shader and a fragment shader both be
2895 * present in a linked program. GL_ARB_ES2_compatibility doesn't say
2896 * anything about shader linking when one of the shaders (vertex or
2897 * fragment shader) is absent. So, the extension shouldn't change the
2898 * behavior specified in GLSL specification.
2900 if (!prog
->SeparateShader
&& ctx
->API
== API_OPENGLES2
) {
2901 if (prog
->_LinkedShaders
[MESA_SHADER_VERTEX
] == NULL
) {
2902 linker_error(prog
, "program lacks a vertex shader\n");
2903 } else if (prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
] == NULL
) {
2904 linker_error(prog
, "program lacks a fragment shader\n");
2908 /* FINISHME: Assign fragment shader output locations. */
2911 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2912 free(shader_list
[i
]);
2913 if (prog
->_LinkedShaders
[i
] == NULL
)
2916 /* Do a final validation step to make sure that the IR wasn't
2917 * invalidated by any modifications performed after intrastage linking.
2919 validate_ir_tree(prog
->_LinkedShaders
[i
]->ir
);
2921 /* Retain any live IR, but trash the rest. */
2922 reparent_ir(prog
->_LinkedShaders
[i
]->ir
, prog
->_LinkedShaders
[i
]->ir
);
2924 /* The symbol table in the linked shaders may contain references to
2925 * variables that were removed (e.g., unused uniforms). Since it may
2926 * contain junk, there is no possible valid use. Delete it and set the
2929 delete prog
->_LinkedShaders
[i
]->symbols
;
2930 prog
->_LinkedShaders
[i
]->symbols
= NULL
;
2933 ralloc_free(mem_ctx
);