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>
67 #include "main/core.h"
68 #include "glsl_symbol_table.h"
69 #include "glsl_parser_extras.h"
72 #include "program/hash_table.h"
74 #include "link_varyings.h"
75 #include "ir_optimization.h"
76 #include "ir_rvalue_visitor.h"
79 #include "main/shaderobj.h"
80 #include "main/enums.h"
83 void linker_error(gl_shader_program
*, const char *, ...);
88 * Visitor that determines whether or not a variable is ever written.
90 class find_assignment_visitor
: public ir_hierarchical_visitor
{
92 find_assignment_visitor(const char *name
)
93 : name(name
), found(false)
98 virtual ir_visitor_status
visit_enter(ir_assignment
*ir
)
100 ir_variable
*const var
= ir
->lhs
->variable_referenced();
102 if (strcmp(name
, var
->name
) == 0) {
107 return visit_continue_with_parent
;
110 virtual ir_visitor_status
visit_enter(ir_call
*ir
)
112 foreach_two_lists(formal_node
, &ir
->callee
->parameters
,
113 actual_node
, &ir
->actual_parameters
) {
114 ir_rvalue
*param_rval
= (ir_rvalue
*) actual_node
;
115 ir_variable
*sig_param
= (ir_variable
*) formal_node
;
117 if (sig_param
->data
.mode
== ir_var_function_out
||
118 sig_param
->data
.mode
== ir_var_function_inout
) {
119 ir_variable
*var
= param_rval
->variable_referenced();
120 if (var
&& strcmp(name
, var
->name
) == 0) {
127 if (ir
->return_deref
!= NULL
) {
128 ir_variable
*const var
= ir
->return_deref
->variable_referenced();
130 if (strcmp(name
, var
->name
) == 0) {
136 return visit_continue_with_parent
;
139 bool variable_found()
145 const char *name
; /**< Find writes to a variable with this name. */
146 bool found
; /**< Was a write to the variable found? */
151 * Visitor that determines whether or not a variable is ever read.
153 class find_deref_visitor
: public ir_hierarchical_visitor
{
155 find_deref_visitor(const char *name
)
156 : name(name
), found(false)
161 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
163 if (strcmp(this->name
, ir
->var
->name
) == 0) {
168 return visit_continue
;
171 bool variable_found() const
177 const char *name
; /**< Find writes to a variable with this name. */
178 bool found
; /**< Was a write to the variable found? */
182 class geom_array_resize_visitor
: public ir_hierarchical_visitor
{
184 unsigned num_vertices
;
185 gl_shader_program
*prog
;
187 geom_array_resize_visitor(unsigned num_vertices
, gl_shader_program
*prog
)
189 this->num_vertices
= num_vertices
;
193 virtual ~geom_array_resize_visitor()
198 virtual ir_visitor_status
visit(ir_variable
*var
)
200 if (!var
->type
->is_array() || var
->data
.mode
!= ir_var_shader_in
)
201 return visit_continue
;
203 unsigned size
= var
->type
->length
;
205 /* Generate a link error if the shader has declared this array with an
208 if (size
&& size
!= this->num_vertices
) {
209 linker_error(this->prog
, "size of array %s declared as %u, "
210 "but number of input vertices is %u\n",
211 var
->name
, size
, this->num_vertices
);
212 return visit_continue
;
215 /* Generate a link error if the shader attempts to access an input
216 * array using an index too large for its actual size assigned at link
219 if (var
->data
.max_array_access
>= this->num_vertices
) {
220 linker_error(this->prog
, "geometry shader accesses element %i of "
221 "%s, but only %i input vertices\n",
222 var
->data
.max_array_access
, var
->name
, this->num_vertices
);
223 return visit_continue
;
226 var
->type
= glsl_type::get_array_instance(var
->type
->element_type(),
228 var
->data
.max_array_access
= this->num_vertices
- 1;
230 return visit_continue
;
233 /* Dereferences of input variables need to be updated so that their type
234 * matches the newly assigned type of the variable they are accessing. */
235 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
237 ir
->type
= ir
->var
->type
;
238 return visit_continue
;
241 /* Dereferences of 2D input arrays need to be updated so that their type
242 * matches the newly assigned type of the array they are accessing. */
243 virtual ir_visitor_status
visit_leave(ir_dereference_array
*ir
)
245 const glsl_type
*const vt
= ir
->array
->type
;
247 ir
->type
= vt
->element_type();
248 return visit_continue
;
254 * Visitor that determines whether or not a shader uses ir_end_primitive.
256 class find_end_primitive_visitor
: public ir_hierarchical_visitor
{
258 find_end_primitive_visitor()
264 virtual ir_visitor_status
visit(ir_end_primitive
*)
270 bool end_primitive_found()
279 } /* anonymous namespace */
282 linker_error(gl_shader_program
*prog
, const char *fmt
, ...)
286 ralloc_strcat(&prog
->InfoLog
, "error: ");
288 ralloc_vasprintf_append(&prog
->InfoLog
, fmt
, ap
);
291 prog
->LinkStatus
= false;
296 linker_warning(gl_shader_program
*prog
, const char *fmt
, ...)
300 ralloc_strcat(&prog
->InfoLog
, "error: ");
302 ralloc_vasprintf_append(&prog
->InfoLog
, fmt
, ap
);
309 * Given a string identifying a program resource, break it into a base name
310 * and an optional array index in square brackets.
312 * If an array index is present, \c out_base_name_end is set to point to the
313 * "[" that precedes the array index, and the array index itself is returned
316 * If no array index is present (or if the array index is negative or
317 * mal-formed), \c out_base_name_end, is set to point to the null terminator
318 * at the end of the input string, and -1 is returned.
320 * Only the final array index is parsed; if the string contains other array
321 * indices (or structure field accesses), they are left in the base name.
323 * No attempt is made to check that the base name is properly formed;
324 * typically the caller will look up the base name in a hash table, so
325 * ill-formed base names simply turn into hash table lookup failures.
328 parse_program_resource_name(const GLchar
*name
,
329 const GLchar
**out_base_name_end
)
331 /* Section 7.3.1 ("Program Interfaces") of the OpenGL 4.3 spec says:
333 * "When an integer array element or block instance number is part of
334 * the name string, it will be specified in decimal form without a "+"
335 * or "-" sign or any extra leading zeroes. Additionally, the name
336 * string will not include white space anywhere in the string."
339 const size_t len
= strlen(name
);
340 *out_base_name_end
= name
+ len
;
342 if (len
== 0 || name
[len
-1] != ']')
345 /* Walk backwards over the string looking for a non-digit character. This
346 * had better be the opening bracket for an array index.
348 * Initially, i specifies the location of the ']'. Since the string may
349 * contain only the ']' charcater, walk backwards very carefully.
352 for (i
= len
- 1; (i
> 0) && isdigit(name
[i
-1]); --i
)
355 if ((i
== 0) || name
[i
-1] != '[')
358 long array_index
= strtol(&name
[i
], NULL
, 10);
362 *out_base_name_end
= name
+ (i
- 1);
368 link_invalidate_variable_locations(exec_list
*ir
)
370 foreach_list(node
, ir
) {
371 ir_variable
*const var
= ((ir_instruction
*) node
)->as_variable();
376 /* Only assign locations for variables that lack an explicit location.
377 * Explicit locations are set for all built-in variables, generic vertex
378 * shader inputs (via layout(location=...)), and generic fragment shader
379 * outputs (also via layout(location=...)).
381 if (!var
->data
.explicit_location
) {
382 var
->data
.location
= -1;
383 var
->data
.location_frac
= 0;
386 /* ir_variable::is_unmatched_generic_inout is used by the linker while
387 * connecting outputs from one stage to inputs of the next stage.
389 * There are two implicit assumptions here. First, we assume that any
390 * built-in variable (i.e., non-generic in or out) will have
391 * explicit_location set. Second, we assume that any generic in or out
392 * will not have explicit_location set.
394 * This second assumption will only be valid until
395 * GL_ARB_separate_shader_objects is supported. When that extension is
396 * implemented, this function will need some modifications.
398 if (!var
->data
.explicit_location
) {
399 var
->data
.is_unmatched_generic_inout
= 1;
401 var
->data
.is_unmatched_generic_inout
= 0;
408 * Set UsesClipDistance and ClipDistanceArraySize based on the given shader.
410 * Also check for errors based on incorrect usage of gl_ClipVertex and
413 * Return false if an error was reported.
416 analyze_clip_usage(struct gl_shader_program
*prog
,
417 struct gl_shader
*shader
, GLboolean
*UsesClipDistance
,
418 GLuint
*ClipDistanceArraySize
)
420 *ClipDistanceArraySize
= 0;
422 if (!prog
->IsES
&& prog
->Version
>= 130) {
423 /* From section 7.1 (Vertex Shader Special Variables) of the
426 * "It is an error for a shader to statically write both
427 * gl_ClipVertex and gl_ClipDistance."
429 * This does not apply to GLSL ES shaders, since GLSL ES defines neither
430 * gl_ClipVertex nor gl_ClipDistance.
432 find_assignment_visitor
clip_vertex("gl_ClipVertex");
433 find_assignment_visitor
clip_distance("gl_ClipDistance");
435 clip_vertex
.run(shader
->ir
);
436 clip_distance
.run(shader
->ir
);
437 if (clip_vertex
.variable_found() && clip_distance
.variable_found()) {
438 linker_error(prog
, "%s shader writes to both `gl_ClipVertex' "
439 "and `gl_ClipDistance'\n",
440 _mesa_shader_stage_to_string(shader
->Stage
));
443 *UsesClipDistance
= clip_distance
.variable_found();
444 ir_variable
*clip_distance_var
=
445 shader
->symbols
->get_variable("gl_ClipDistance");
446 if (clip_distance_var
)
447 *ClipDistanceArraySize
= clip_distance_var
->type
->length
;
449 *UsesClipDistance
= false;
455 * Verify that a vertex shader executable meets all semantic requirements.
457 * Also sets prog->Vert.UsesClipDistance and prog->Vert.ClipDistanceArraySize
460 * \param shader Vertex shader executable to be verified
463 validate_vertex_shader_executable(struct gl_shader_program
*prog
,
464 struct gl_shader
*shader
)
469 /* From the GLSL 1.10 spec, page 48:
471 * "The variable gl_Position is available only in the vertex
472 * language and is intended for writing the homogeneous vertex
473 * position. All executions of a well-formed vertex shader
474 * executable must write a value into this variable. [...] The
475 * variable gl_Position is available only in the vertex
476 * language and is intended for writing the homogeneous vertex
477 * position. All executions of a well-formed vertex shader
478 * executable must write a value into this variable."
480 * while in GLSL 1.40 this text is changed to:
482 * "The variable gl_Position is available only in the vertex
483 * language and is intended for writing the homogeneous vertex
484 * position. It can be written at any time during shader
485 * execution. It may also be read back by a vertex shader
486 * after being written. This value will be used by primitive
487 * assembly, clipping, culling, and other fixed functionality
488 * operations, if present, that operate on primitives after
489 * vertex processing has occurred. Its value is undefined if
490 * the vertex shader executable does not write gl_Position."
492 * GLSL ES 3.00 is similar to GLSL 1.40--failing to write to gl_Position is
495 if (prog
->Version
< (prog
->IsES
? 300 : 140)) {
496 find_assignment_visitor
find("gl_Position");
497 find
.run(shader
->ir
);
498 if (!find
.variable_found()) {
499 linker_error(prog
, "vertex shader does not write to `gl_Position'\n");
504 analyze_clip_usage(prog
, shader
, &prog
->Vert
.UsesClipDistance
,
505 &prog
->Vert
.ClipDistanceArraySize
);
510 * Verify that a fragment shader executable meets all semantic requirements
512 * \param shader Fragment shader executable to be verified
515 validate_fragment_shader_executable(struct gl_shader_program
*prog
,
516 struct gl_shader
*shader
)
521 find_assignment_visitor
frag_color("gl_FragColor");
522 find_assignment_visitor
frag_data("gl_FragData");
524 frag_color
.run(shader
->ir
);
525 frag_data
.run(shader
->ir
);
527 if (frag_color
.variable_found() && frag_data
.variable_found()) {
528 linker_error(prog
, "fragment shader writes to both "
529 "`gl_FragColor' and `gl_FragData'\n");
534 * Verify that a geometry shader executable meets all semantic requirements
536 * Also sets prog->Geom.VerticesIn, prog->Geom.UsesClipDistance, and
537 * prog->Geom.ClipDistanceArraySize as a side effect.
539 * \param shader Geometry shader executable to be verified
542 validate_geometry_shader_executable(struct gl_shader_program
*prog
,
543 struct gl_shader
*shader
)
548 unsigned num_vertices
= vertices_per_prim(prog
->Geom
.InputType
);
549 prog
->Geom
.VerticesIn
= num_vertices
;
551 analyze_clip_usage(prog
, shader
, &prog
->Geom
.UsesClipDistance
,
552 &prog
->Geom
.ClipDistanceArraySize
);
554 find_end_primitive_visitor end_primitive
;
555 end_primitive
.run(shader
->ir
);
556 prog
->Geom
.UsesEndPrimitive
= end_primitive
.end_primitive_found();
561 * Perform validation of global variables used across multiple shaders
564 cross_validate_globals(struct gl_shader_program
*prog
,
565 struct gl_shader
**shader_list
,
566 unsigned num_shaders
,
569 /* Examine all of the uniforms in all of the shaders and cross validate
572 glsl_symbol_table variables
;
573 for (unsigned i
= 0; i
< num_shaders
; i
++) {
574 if (shader_list
[i
] == NULL
)
577 foreach_list(node
, shader_list
[i
]->ir
) {
578 ir_variable
*const var
= ((ir_instruction
*) node
)->as_variable();
583 if (uniforms_only
&& (var
->data
.mode
!= ir_var_uniform
))
586 /* Don't cross validate temporaries that are at global scope. These
587 * will eventually get pulled into the shaders 'main'.
589 if (var
->data
.mode
== ir_var_temporary
)
592 /* If a global with this name has already been seen, verify that the
593 * new instance has the same type. In addition, if the globals have
594 * initializers, the values of the initializers must be the same.
596 ir_variable
*const existing
= variables
.get_variable(var
->name
);
597 if (existing
!= NULL
) {
598 if (var
->type
!= existing
->type
) {
599 /* Consider the types to be "the same" if both types are arrays
600 * of the same type and one of the arrays is implicitly sized.
601 * In addition, set the type of the linked variable to the
602 * explicitly sized array.
604 if (var
->type
->is_array()
605 && existing
->type
->is_array()
606 && (var
->type
->fields
.array
== existing
->type
->fields
.array
)
607 && ((var
->type
->length
== 0)
608 || (existing
->type
->length
== 0))) {
609 if (var
->type
->length
!= 0) {
610 existing
->type
= var
->type
;
612 } else if (var
->type
->is_record()
613 && existing
->type
->is_record()
614 && existing
->type
->record_compare(var
->type
)) {
615 existing
->type
= var
->type
;
617 linker_error(prog
, "%s `%s' declared as type "
618 "`%s' and type `%s'\n",
620 var
->name
, var
->type
->name
,
621 existing
->type
->name
);
626 if (var
->data
.explicit_location
) {
627 if (existing
->data
.explicit_location
628 && (var
->data
.location
!= existing
->data
.location
)) {
629 linker_error(prog
, "explicit locations for %s "
630 "`%s' have differing values\n",
631 mode_string(var
), var
->name
);
635 existing
->data
.location
= var
->data
.location
;
636 existing
->data
.explicit_location
= true;
639 /* From the GLSL 4.20 specification:
640 * "A link error will result if two compilation units in a program
641 * specify different integer-constant bindings for the same
642 * opaque-uniform name. However, it is not an error to specify a
643 * binding on some but not all declarations for the same name"
645 if (var
->data
.explicit_binding
) {
646 if (existing
->data
.explicit_binding
&&
647 var
->data
.binding
!= existing
->data
.binding
) {
648 linker_error(prog
, "explicit bindings for %s "
649 "`%s' have differing values\n",
650 mode_string(var
), var
->name
);
654 existing
->data
.binding
= var
->data
.binding
;
655 existing
->data
.explicit_binding
= true;
658 if (var
->type
->contains_atomic() &&
659 var
->data
.atomic
.offset
!= existing
->data
.atomic
.offset
) {
660 linker_error(prog
, "offset specifications for %s "
661 "`%s' have differing values\n",
662 mode_string(var
), var
->name
);
666 /* Validate layout qualifiers for gl_FragDepth.
668 * From the AMD/ARB_conservative_depth specs:
670 * "If gl_FragDepth is redeclared in any fragment shader in a
671 * program, it must be redeclared in all fragment shaders in
672 * that program that have static assignments to
673 * gl_FragDepth. All redeclarations of gl_FragDepth in all
674 * fragment shaders in a single program must have the same set
677 if (strcmp(var
->name
, "gl_FragDepth") == 0) {
678 bool layout_declared
= var
->data
.depth_layout
!= ir_depth_layout_none
;
679 bool layout_differs
=
680 var
->data
.depth_layout
!= existing
->data
.depth_layout
;
682 if (layout_declared
&& layout_differs
) {
684 "All redeclarations of gl_FragDepth in all "
685 "fragment shaders in a single program must have "
686 "the same set of qualifiers.");
689 if (var
->data
.used
&& layout_differs
) {
691 "If gl_FragDepth is redeclared with a layout "
692 "qualifier in any fragment shader, it must be "
693 "redeclared with the same layout qualifier in "
694 "all fragment shaders that have assignments to "
699 /* Page 35 (page 41 of the PDF) of the GLSL 4.20 spec says:
701 * "If a shared global has multiple initializers, the
702 * initializers must all be constant expressions, and they
703 * must all have the same value. Otherwise, a link error will
704 * result. (A shared global having only one initializer does
705 * not require that initializer to be a constant expression.)"
707 * Previous to 4.20 the GLSL spec simply said that initializers
708 * must have the same value. In this case of non-constant
709 * initializers, this was impossible to determine. As a result,
710 * no vendor actually implemented that behavior. The 4.20
711 * behavior matches the implemented behavior of at least one other
712 * vendor, so we'll implement that for all GLSL versions.
714 if (var
->constant_initializer
!= NULL
) {
715 if (existing
->constant_initializer
!= NULL
) {
716 if (!var
->constant_initializer
->has_value(existing
->constant_initializer
)) {
717 linker_error(prog
, "initializers for %s "
718 "`%s' have differing values\n",
719 mode_string(var
), var
->name
);
723 /* If the first-seen instance of a particular uniform did not
724 * have an initializer but a later instance does, copy the
725 * initializer to the version stored in the symbol table.
727 /* FINISHME: This is wrong. The constant_value field should
728 * FINISHME: not be modified! Imagine a case where a shader
729 * FINISHME: without an initializer is linked in two different
730 * FINISHME: programs with shaders that have differing
731 * FINISHME: initializers. Linking with the first will
732 * FINISHME: modify the shader, and linking with the second
733 * FINISHME: will fail.
735 existing
->constant_initializer
=
736 var
->constant_initializer
->clone(ralloc_parent(existing
),
741 if (var
->data
.has_initializer
) {
742 if (existing
->data
.has_initializer
743 && (var
->constant_initializer
== NULL
744 || existing
->constant_initializer
== NULL
)) {
746 "shared global variable `%s' has multiple "
747 "non-constant initializers.\n",
752 /* Some instance had an initializer, so keep track of that. In
753 * this location, all sorts of initializers (constant or
754 * otherwise) will propagate the existence to the variable
755 * stored in the symbol table.
757 existing
->data
.has_initializer
= true;
760 if (existing
->data
.invariant
!= var
->data
.invariant
) {
761 linker_error(prog
, "declarations for %s `%s' have "
762 "mismatching invariant qualifiers\n",
763 mode_string(var
), var
->name
);
766 if (existing
->data
.centroid
!= var
->data
.centroid
) {
767 linker_error(prog
, "declarations for %s `%s' have "
768 "mismatching centroid qualifiers\n",
769 mode_string(var
), var
->name
);
772 if (existing
->data
.sample
!= var
->data
.sample
) {
773 linker_error(prog
, "declarations for %s `%s` have "
774 "mismatching sample qualifiers\n",
775 mode_string(var
), var
->name
);
779 variables
.add_variable(var
);
786 * Perform validation of uniforms used across multiple shader stages
789 cross_validate_uniforms(struct gl_shader_program
*prog
)
791 cross_validate_globals(prog
, prog
->_LinkedShaders
,
792 MESA_SHADER_STAGES
, true);
796 * Accumulates the array of prog->UniformBlocks and checks that all
797 * definitons of blocks agree on their contents.
800 interstage_cross_validate_uniform_blocks(struct gl_shader_program
*prog
)
802 unsigned max_num_uniform_blocks
= 0;
803 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
804 if (prog
->_LinkedShaders
[i
])
805 max_num_uniform_blocks
+= prog
->_LinkedShaders
[i
]->NumUniformBlocks
;
808 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
809 struct gl_shader
*sh
= prog
->_LinkedShaders
[i
];
811 prog
->UniformBlockStageIndex
[i
] = ralloc_array(prog
, int,
812 max_num_uniform_blocks
);
813 for (unsigned int j
= 0; j
< max_num_uniform_blocks
; j
++)
814 prog
->UniformBlockStageIndex
[i
][j
] = -1;
819 for (unsigned int j
= 0; j
< sh
->NumUniformBlocks
; j
++) {
820 int index
= link_cross_validate_uniform_block(prog
,
821 &prog
->UniformBlocks
,
822 &prog
->NumUniformBlocks
,
823 &sh
->UniformBlocks
[j
]);
826 linker_error(prog
, "uniform block `%s' has mismatching definitions",
827 sh
->UniformBlocks
[j
].Name
);
831 prog
->UniformBlockStageIndex
[i
][index
] = j
;
840 * Populates a shaders symbol table with all global declarations
843 populate_symbol_table(gl_shader
*sh
)
845 sh
->symbols
= new(sh
) glsl_symbol_table
;
847 foreach_list(node
, sh
->ir
) {
848 ir_instruction
*const inst
= (ir_instruction
*) node
;
852 if ((func
= inst
->as_function()) != NULL
) {
853 sh
->symbols
->add_function(func
);
854 } else if ((var
= inst
->as_variable()) != NULL
) {
855 sh
->symbols
->add_variable(var
);
862 * Remap variables referenced in an instruction tree
864 * This is used when instruction trees are cloned from one shader and placed in
865 * another. These trees will contain references to \c ir_variable nodes that
866 * do not exist in the target shader. This function finds these \c ir_variable
867 * references and replaces the references with matching variables in the target
870 * If there is no matching variable in the target shader, a clone of the
871 * \c ir_variable is made and added to the target shader. The new variable is
872 * added to \b both the instruction stream and the symbol table.
874 * \param inst IR tree that is to be processed.
875 * \param symbols Symbol table containing global scope symbols in the
877 * \param instructions Instruction stream where new variable declarations
881 remap_variables(ir_instruction
*inst
, struct gl_shader
*target
,
884 class remap_visitor
: public ir_hierarchical_visitor
{
886 remap_visitor(struct gl_shader
*target
,
889 this->target
= target
;
890 this->symbols
= target
->symbols
;
891 this->instructions
= target
->ir
;
895 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
897 if (ir
->var
->data
.mode
== ir_var_temporary
) {
898 ir_variable
*var
= (ir_variable
*) hash_table_find(temps
, ir
->var
);
902 return visit_continue
;
905 ir_variable
*const existing
=
906 this->symbols
->get_variable(ir
->var
->name
);
907 if (existing
!= NULL
)
910 ir_variable
*copy
= ir
->var
->clone(this->target
, NULL
);
912 this->symbols
->add_variable(copy
);
913 this->instructions
->push_head(copy
);
917 return visit_continue
;
921 struct gl_shader
*target
;
922 glsl_symbol_table
*symbols
;
923 exec_list
*instructions
;
927 remap_visitor
v(target
, temps
);
934 * Move non-declarations from one instruction stream to another
936 * The intended usage pattern of this function is to pass the pointer to the
937 * head sentinel of a list (i.e., a pointer to the list cast to an \c exec_node
938 * pointer) for \c last and \c false for \c make_copies on the first
939 * call. Successive calls pass the return value of the previous call for
940 * \c last and \c true for \c make_copies.
942 * \param instructions Source instruction stream
943 * \param last Instruction after which new instructions should be
944 * inserted in the target instruction stream
945 * \param make_copies Flag selecting whether instructions in \c instructions
946 * should be copied (via \c ir_instruction::clone) into the
947 * target list or moved.
950 * The new "last" instruction in the target instruction stream. This pointer
951 * is suitable for use as the \c last parameter of a later call to this
955 move_non_declarations(exec_list
*instructions
, exec_node
*last
,
956 bool make_copies
, gl_shader
*target
)
958 hash_table
*temps
= NULL
;
961 temps
= hash_table_ctor(0, hash_table_pointer_hash
,
962 hash_table_pointer_compare
);
964 foreach_list_safe(node
, instructions
) {
965 ir_instruction
*inst
= (ir_instruction
*) node
;
967 if (inst
->as_function())
970 ir_variable
*var
= inst
->as_variable();
971 if ((var
!= NULL
) && (var
->data
.mode
!= ir_var_temporary
))
974 assert(inst
->as_assignment()
976 || inst
->as_if() /* for initializers with the ?: operator */
977 || ((var
!= NULL
) && (var
->data
.mode
== ir_var_temporary
)));
980 inst
= inst
->clone(target
, NULL
);
983 hash_table_insert(temps
, inst
, var
);
985 remap_variables(inst
, target
, temps
);
990 last
->insert_after(inst
);
995 hash_table_dtor(temps
);
1001 * Get the function signature for main from a shader
1003 static ir_function_signature
*
1004 get_main_function_signature(gl_shader
*sh
)
1006 ir_function
*const f
= sh
->symbols
->get_function("main");
1008 exec_list void_parameters
;
1010 /* Look for the 'void main()' signature and ensure that it's defined.
1011 * This keeps the linker from accidentally pick a shader that just
1012 * contains a prototype for main.
1014 * We don't have to check for multiple definitions of main (in multiple
1015 * shaders) because that would have already been caught above.
1017 ir_function_signature
*sig
= f
->matching_signature(NULL
, &void_parameters
);
1018 if ((sig
!= NULL
) && sig
->is_defined
) {
1028 * This class is only used in link_intrastage_shaders() below but declaring
1029 * it inside that function leads to compiler warnings with some versions of
1032 class array_sizing_visitor
: public ir_hierarchical_visitor
{
1034 array_sizing_visitor()
1035 : mem_ctx(ralloc_context(NULL
)),
1036 unnamed_interfaces(hash_table_ctor(0, hash_table_pointer_hash
,
1037 hash_table_pointer_compare
))
1041 ~array_sizing_visitor()
1043 hash_table_dtor(this->unnamed_interfaces
);
1044 ralloc_free(this->mem_ctx
);
1047 virtual ir_visitor_status
visit(ir_variable
*var
)
1049 fixup_type(&var
->type
, var
->data
.max_array_access
);
1050 if (var
->type
->is_interface()) {
1051 if (interface_contains_unsized_arrays(var
->type
)) {
1052 const glsl_type
*new_type
=
1053 resize_interface_members(var
->type
, var
->max_ifc_array_access
);
1054 var
->type
= new_type
;
1055 var
->change_interface_type(new_type
);
1057 } else if (var
->type
->is_array() &&
1058 var
->type
->fields
.array
->is_interface()) {
1059 if (interface_contains_unsized_arrays(var
->type
->fields
.array
)) {
1060 const glsl_type
*new_type
=
1061 resize_interface_members(var
->type
->fields
.array
,
1062 var
->max_ifc_array_access
);
1063 var
->change_interface_type(new_type
);
1065 glsl_type::get_array_instance(new_type
, var
->type
->length
);
1067 } else if (const glsl_type
*ifc_type
= var
->get_interface_type()) {
1068 /* Store a pointer to the variable in the unnamed_interfaces
1071 ir_variable
**interface_vars
= (ir_variable
**)
1072 hash_table_find(this->unnamed_interfaces
, ifc_type
);
1073 if (interface_vars
== NULL
) {
1074 interface_vars
= rzalloc_array(mem_ctx
, ir_variable
*,
1076 hash_table_insert(this->unnamed_interfaces
, interface_vars
,
1079 unsigned index
= ifc_type
->field_index(var
->name
);
1080 assert(index
< ifc_type
->length
);
1081 assert(interface_vars
[index
] == NULL
);
1082 interface_vars
[index
] = var
;
1084 return visit_continue
;
1088 * For each unnamed interface block that was discovered while running the
1089 * visitor, adjust the interface type to reflect the newly assigned array
1090 * sizes, and fix up the ir_variable nodes to point to the new interface
1093 void fixup_unnamed_interface_types()
1095 hash_table_call_foreach(this->unnamed_interfaces
,
1096 fixup_unnamed_interface_type
, NULL
);
1101 * If the type pointed to by \c type represents an unsized array, replace
1102 * it with a sized array whose size is determined by max_array_access.
1104 static void fixup_type(const glsl_type
**type
, unsigned max_array_access
)
1106 if ((*type
)->is_unsized_array()) {
1107 *type
= glsl_type::get_array_instance((*type
)->fields
.array
,
1108 max_array_access
+ 1);
1109 assert(*type
!= NULL
);
1114 * Determine whether the given interface type contains unsized arrays (if
1115 * it doesn't, array_sizing_visitor doesn't need to process it).
1117 static bool interface_contains_unsized_arrays(const glsl_type
*type
)
1119 for (unsigned i
= 0; i
< type
->length
; i
++) {
1120 const glsl_type
*elem_type
= type
->fields
.structure
[i
].type
;
1121 if (elem_type
->is_unsized_array())
1128 * Create a new interface type based on the given type, with unsized arrays
1129 * replaced by sized arrays whose size is determined by
1130 * max_ifc_array_access.
1132 static const glsl_type
*
1133 resize_interface_members(const glsl_type
*type
,
1134 const unsigned *max_ifc_array_access
)
1136 unsigned num_fields
= type
->length
;
1137 glsl_struct_field
*fields
= new glsl_struct_field
[num_fields
];
1138 memcpy(fields
, type
->fields
.structure
,
1139 num_fields
* sizeof(*fields
));
1140 for (unsigned i
= 0; i
< num_fields
; i
++) {
1141 fixup_type(&fields
[i
].type
, max_ifc_array_access
[i
]);
1143 glsl_interface_packing packing
=
1144 (glsl_interface_packing
) type
->interface_packing
;
1145 const glsl_type
*new_ifc_type
=
1146 glsl_type::get_interface_instance(fields
, num_fields
,
1147 packing
, type
->name
);
1149 return new_ifc_type
;
1152 static void fixup_unnamed_interface_type(const void *key
, void *data
,
1155 const glsl_type
*ifc_type
= (const glsl_type
*) key
;
1156 ir_variable
**interface_vars
= (ir_variable
**) data
;
1157 unsigned num_fields
= ifc_type
->length
;
1158 glsl_struct_field
*fields
= new glsl_struct_field
[num_fields
];
1159 memcpy(fields
, ifc_type
->fields
.structure
,
1160 num_fields
* sizeof(*fields
));
1161 bool interface_type_changed
= false;
1162 for (unsigned i
= 0; i
< num_fields
; i
++) {
1163 if (interface_vars
[i
] != NULL
&&
1164 fields
[i
].type
!= interface_vars
[i
]->type
) {
1165 fields
[i
].type
= interface_vars
[i
]->type
;
1166 interface_type_changed
= true;
1169 if (!interface_type_changed
) {
1173 glsl_interface_packing packing
=
1174 (glsl_interface_packing
) ifc_type
->interface_packing
;
1175 const glsl_type
*new_ifc_type
=
1176 glsl_type::get_interface_instance(fields
, num_fields
, packing
,
1179 for (unsigned i
= 0; i
< num_fields
; i
++) {
1180 if (interface_vars
[i
] != NULL
)
1181 interface_vars
[i
]->change_interface_type(new_ifc_type
);
1186 * Memory context used to allocate the data in \c unnamed_interfaces.
1191 * Hash table from const glsl_type * to an array of ir_variable *'s
1192 * pointing to the ir_variables constituting each unnamed interface block.
1194 hash_table
*unnamed_interfaces
;
1198 * Performs the cross-validation of geometry shader max_vertices and
1199 * primitive type layout qualifiers for the attached geometry shaders,
1200 * and propagates them to the linked GS and linked shader program.
1203 link_gs_inout_layout_qualifiers(struct gl_shader_program
*prog
,
1204 struct gl_shader
*linked_shader
,
1205 struct gl_shader
**shader_list
,
1206 unsigned num_shaders
)
1208 linked_shader
->Geom
.VerticesOut
= 0;
1209 linked_shader
->Geom
.InputType
= PRIM_UNKNOWN
;
1210 linked_shader
->Geom
.OutputType
= PRIM_UNKNOWN
;
1212 /* No in/out qualifiers defined for anything but GLSL 1.50+
1213 * geometry shaders so far.
1215 if (linked_shader
->Stage
!= MESA_SHADER_GEOMETRY
|| prog
->Version
< 150)
1218 /* From the GLSL 1.50 spec, page 46:
1220 * "All geometry shader output layout declarations in a program
1221 * must declare the same layout and same value for
1222 * max_vertices. There must be at least one geometry output
1223 * layout declaration somewhere in a program, but not all
1224 * geometry shaders (compilation units) are required to
1228 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1229 struct gl_shader
*shader
= shader_list
[i
];
1231 if (shader
->Geom
.InputType
!= PRIM_UNKNOWN
) {
1232 if (linked_shader
->Geom
.InputType
!= PRIM_UNKNOWN
&&
1233 linked_shader
->Geom
.InputType
!= shader
->Geom
.InputType
) {
1234 linker_error(prog
, "geometry shader defined with conflicting "
1238 linked_shader
->Geom
.InputType
= shader
->Geom
.InputType
;
1241 if (shader
->Geom
.OutputType
!= PRIM_UNKNOWN
) {
1242 if (linked_shader
->Geom
.OutputType
!= PRIM_UNKNOWN
&&
1243 linked_shader
->Geom
.OutputType
!= shader
->Geom
.OutputType
) {
1244 linker_error(prog
, "geometry shader defined with conflicting "
1248 linked_shader
->Geom
.OutputType
= shader
->Geom
.OutputType
;
1251 if (shader
->Geom
.VerticesOut
!= 0) {
1252 if (linked_shader
->Geom
.VerticesOut
!= 0 &&
1253 linked_shader
->Geom
.VerticesOut
!= shader
->Geom
.VerticesOut
) {
1254 linker_error(prog
, "geometry shader defined with conflicting "
1255 "output vertex count (%d and %d)\n",
1256 linked_shader
->Geom
.VerticesOut
,
1257 shader
->Geom
.VerticesOut
);
1260 linked_shader
->Geom
.VerticesOut
= shader
->Geom
.VerticesOut
;
1264 /* Just do the intrastage -> interstage propagation right now,
1265 * since we already know we're in the right type of shader program
1268 if (linked_shader
->Geom
.InputType
== PRIM_UNKNOWN
) {
1270 "geometry shader didn't declare primitive input type\n");
1273 prog
->Geom
.InputType
= linked_shader
->Geom
.InputType
;
1275 if (linked_shader
->Geom
.OutputType
== PRIM_UNKNOWN
) {
1277 "geometry shader didn't declare primitive output type\n");
1280 prog
->Geom
.OutputType
= linked_shader
->Geom
.OutputType
;
1282 if (linked_shader
->Geom
.VerticesOut
== 0) {
1284 "geometry shader didn't declare max_vertices\n");
1287 prog
->Geom
.VerticesOut
= linked_shader
->Geom
.VerticesOut
;
1291 * Combine a group of shaders for a single stage to generate a linked shader
1294 * If this function is supplied a single shader, it is cloned, and the new
1295 * shader is returned.
1297 static struct gl_shader
*
1298 link_intrastage_shaders(void *mem_ctx
,
1299 struct gl_context
*ctx
,
1300 struct gl_shader_program
*prog
,
1301 struct gl_shader
**shader_list
,
1302 unsigned num_shaders
)
1304 struct gl_uniform_block
*uniform_blocks
= NULL
;
1306 /* Check that global variables defined in multiple shaders are consistent.
1308 cross_validate_globals(prog
, shader_list
, num_shaders
, false);
1309 if (!prog
->LinkStatus
)
1312 /* Check that interface blocks defined in multiple shaders are consistent.
1314 validate_intrastage_interface_blocks(prog
, (const gl_shader
**)shader_list
,
1316 if (!prog
->LinkStatus
)
1319 /* Link up uniform blocks defined within this stage. */
1320 const unsigned num_uniform_blocks
=
1321 link_uniform_blocks(mem_ctx
, prog
, shader_list
, num_shaders
,
1324 /* Check that there is only a single definition of each function signature
1325 * across all shaders.
1327 for (unsigned i
= 0; i
< (num_shaders
- 1); i
++) {
1328 foreach_list(node
, shader_list
[i
]->ir
) {
1329 ir_function
*const f
= ((ir_instruction
*) node
)->as_function();
1334 for (unsigned j
= i
+ 1; j
< num_shaders
; j
++) {
1335 ir_function
*const other
=
1336 shader_list
[j
]->symbols
->get_function(f
->name
);
1338 /* If the other shader has no function (and therefore no function
1339 * signatures) with the same name, skip to the next shader.
1344 foreach_list(n
, &f
->signatures
) {
1345 ir_function_signature
*sig
= (ir_function_signature
*) n
;
1347 if (!sig
->is_defined
|| sig
->is_builtin())
1350 ir_function_signature
*other_sig
=
1351 other
->exact_matching_signature(NULL
, &sig
->parameters
);
1353 if ((other_sig
!= NULL
) && other_sig
->is_defined
1354 && !other_sig
->is_builtin()) {
1355 linker_error(prog
, "function `%s' is multiply defined",
1364 /* Find the shader that defines main, and make a clone of it.
1366 * Starting with the clone, search for undefined references. If one is
1367 * found, find the shader that defines it. Clone the reference and add
1368 * it to the shader. Repeat until there are no undefined references or
1369 * until a reference cannot be resolved.
1371 gl_shader
*main
= NULL
;
1372 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1373 if (get_main_function_signature(shader_list
[i
]) != NULL
) {
1374 main
= shader_list
[i
];
1380 linker_error(prog
, "%s shader lacks `main'\n",
1381 _mesa_shader_stage_to_string(shader_list
[0]->Stage
));
1385 gl_shader
*linked
= ctx
->Driver
.NewShader(NULL
, 0, main
->Type
);
1386 linked
->ir
= new(linked
) exec_list
;
1387 clone_ir_list(mem_ctx
, linked
->ir
, main
->ir
);
1389 linked
->UniformBlocks
= uniform_blocks
;
1390 linked
->NumUniformBlocks
= num_uniform_blocks
;
1391 ralloc_steal(linked
, linked
->UniformBlocks
);
1393 link_gs_inout_layout_qualifiers(prog
, linked
, shader_list
, num_shaders
);
1395 populate_symbol_table(linked
);
1397 /* The a pointer to the main function in the final linked shader (i.e., the
1398 * copy of the original shader that contained the main function).
1400 ir_function_signature
*const main_sig
= get_main_function_signature(linked
);
1402 /* Move any instructions other than variable declarations or function
1403 * declarations into main.
1405 exec_node
*insertion_point
=
1406 move_non_declarations(linked
->ir
, (exec_node
*) &main_sig
->body
, false,
1409 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1410 if (shader_list
[i
] == main
)
1413 insertion_point
= move_non_declarations(shader_list
[i
]->ir
,
1414 insertion_point
, true, linked
);
1417 /* Check if any shader needs built-in functions. */
1418 bool need_builtins
= false;
1419 for (unsigned i
= 0; i
< num_shaders
; i
++) {
1420 if (shader_list
[i
]->uses_builtin_functions
) {
1421 need_builtins
= true;
1427 if (need_builtins
) {
1428 /* Make a temporary array one larger than shader_list, which will hold
1429 * the built-in function shader as well.
1431 gl_shader
**linking_shaders
= (gl_shader
**)
1432 calloc(num_shaders
+ 1, sizeof(gl_shader
*));
1433 memcpy(linking_shaders
, shader_list
, num_shaders
* sizeof(gl_shader
*));
1434 linking_shaders
[num_shaders
] = _mesa_glsl_get_builtin_function_shader();
1436 ok
= link_function_calls(prog
, linked
, linking_shaders
, num_shaders
+ 1);
1438 free(linking_shaders
);
1440 ok
= link_function_calls(prog
, linked
, shader_list
, num_shaders
);
1445 ctx
->Driver
.DeleteShader(ctx
, linked
);
1449 /* At this point linked should contain all of the linked IR, so
1450 * validate it to make sure nothing went wrong.
1452 validate_ir_tree(linked
->ir
);
1454 /* Set the size of geometry shader input arrays */
1455 if (linked
->Stage
== MESA_SHADER_GEOMETRY
) {
1456 unsigned num_vertices
= vertices_per_prim(prog
->Geom
.InputType
);
1457 geom_array_resize_visitor
input_resize_visitor(num_vertices
, prog
);
1458 foreach_list(n
, linked
->ir
) {
1459 ir_instruction
*ir
= (ir_instruction
*) n
;
1460 ir
->accept(&input_resize_visitor
);
1464 /* Make a pass over all variable declarations to ensure that arrays with
1465 * unspecified sizes have a size specified. The size is inferred from the
1466 * max_array_access field.
1468 array_sizing_visitor v
;
1470 v
.fixup_unnamed_interface_types();
1476 * Update the sizes of linked shader uniform arrays to the maximum
1479 * From page 81 (page 95 of the PDF) of the OpenGL 2.1 spec:
1481 * If one or more elements of an array are active,
1482 * GetActiveUniform will return the name of the array in name,
1483 * subject to the restrictions listed above. The type of the array
1484 * is returned in type. The size parameter contains the highest
1485 * array element index used, plus one. The compiler or linker
1486 * determines the highest index used. There will be only one
1487 * active uniform reported by the GL per uniform array.
1491 update_array_sizes(struct gl_shader_program
*prog
)
1493 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
1494 if (prog
->_LinkedShaders
[i
] == NULL
)
1497 foreach_list(node
, prog
->_LinkedShaders
[i
]->ir
) {
1498 ir_variable
*const var
= ((ir_instruction
*) node
)->as_variable();
1500 if ((var
== NULL
) || (var
->data
.mode
!= ir_var_uniform
) ||
1501 !var
->type
->is_array())
1504 /* GL_ARB_uniform_buffer_object says that std140 uniforms
1505 * will not be eliminated. Since we always do std140, just
1506 * don't resize arrays in UBOs.
1508 * Atomic counters are supposed to get deterministic
1509 * locations assigned based on the declaration ordering and
1510 * sizes, array compaction would mess that up.
1512 if (var
->is_in_uniform_block() || var
->type
->contains_atomic())
1515 unsigned int size
= var
->data
.max_array_access
;
1516 for (unsigned j
= 0; j
< MESA_SHADER_STAGES
; j
++) {
1517 if (prog
->_LinkedShaders
[j
] == NULL
)
1520 foreach_list(node2
, prog
->_LinkedShaders
[j
]->ir
) {
1521 ir_variable
*other_var
= ((ir_instruction
*) node2
)->as_variable();
1525 if (strcmp(var
->name
, other_var
->name
) == 0 &&
1526 other_var
->data
.max_array_access
> size
) {
1527 size
= other_var
->data
.max_array_access
;
1532 if (size
+ 1 != var
->type
->length
) {
1533 /* If this is a built-in uniform (i.e., it's backed by some
1534 * fixed-function state), adjust the number of state slots to
1535 * match the new array size. The number of slots per array entry
1536 * is not known. It seems safe to assume that the total number of
1537 * slots is an integer multiple of the number of array elements.
1538 * Determine the number of slots per array element by dividing by
1539 * the old (total) size.
1541 if (var
->num_state_slots
> 0) {
1542 var
->num_state_slots
= (size
+ 1)
1543 * (var
->num_state_slots
/ var
->type
->length
);
1546 var
->type
= glsl_type::get_array_instance(var
->type
->fields
.array
,
1548 /* FINISHME: We should update the types of array
1549 * dereferences of this variable now.
1557 * Find a contiguous set of available bits in a bitmask.
1559 * \param used_mask Bits representing used (1) and unused (0) locations
1560 * \param needed_count Number of contiguous bits needed.
1563 * Base location of the available bits on success or -1 on failure.
1566 find_available_slots(unsigned used_mask
, unsigned needed_count
)
1568 unsigned needed_mask
= (1 << needed_count
) - 1;
1569 const int max_bit_to_test
= (8 * sizeof(used_mask
)) - needed_count
;
1571 /* The comparison to 32 is redundant, but without it GCC emits "warning:
1572 * cannot optimize possibly infinite loops" for the loop below.
1574 if ((needed_count
== 0) || (max_bit_to_test
< 0) || (max_bit_to_test
> 32))
1577 for (int i
= 0; i
<= max_bit_to_test
; i
++) {
1578 if ((needed_mask
& ~used_mask
) == needed_mask
)
1589 * Assign locations for either VS inputs for FS outputs
1591 * \param prog Shader program whose variables need locations assigned
1592 * \param target_index Selector for the program target to receive location
1593 * assignmnets. Must be either \c MESA_SHADER_VERTEX or
1594 * \c MESA_SHADER_FRAGMENT.
1595 * \param max_index Maximum number of generic locations. This corresponds
1596 * to either the maximum number of draw buffers or the
1597 * maximum number of generic attributes.
1600 * If locations are successfully assigned, true is returned. Otherwise an
1601 * error is emitted to the shader link log and false is returned.
1604 assign_attribute_or_color_locations(gl_shader_program
*prog
,
1605 unsigned target_index
,
1608 /* Mark invalid locations as being used.
1610 unsigned used_locations
= (max_index
>= 32)
1611 ? ~0 : ~((1 << max_index
) - 1);
1613 assert((target_index
== MESA_SHADER_VERTEX
)
1614 || (target_index
== MESA_SHADER_FRAGMENT
));
1616 gl_shader
*const sh
= prog
->_LinkedShaders
[target_index
];
1620 /* Operate in a total of four passes.
1622 * 1. Invalidate the location assignments for all vertex shader inputs.
1624 * 2. Assign locations for inputs that have user-defined (via
1625 * glBindVertexAttribLocation) locations and outputs that have
1626 * user-defined locations (via glBindFragDataLocation).
1628 * 3. Sort the attributes without assigned locations by number of slots
1629 * required in decreasing order. Fragmentation caused by attribute
1630 * locations assigned by the application may prevent large attributes
1631 * from having enough contiguous space.
1633 * 4. Assign locations to any inputs without assigned locations.
1636 const int generic_base
= (target_index
== MESA_SHADER_VERTEX
)
1637 ? (int) VERT_ATTRIB_GENERIC0
: (int) FRAG_RESULT_DATA0
;
1639 const enum ir_variable_mode direction
=
1640 (target_index
== MESA_SHADER_VERTEX
)
1641 ? ir_var_shader_in
: ir_var_shader_out
;
1644 /* Temporary storage for the set of attributes that need locations assigned.
1650 /* Used below in the call to qsort. */
1651 static int compare(const void *a
, const void *b
)
1653 const temp_attr
*const l
= (const temp_attr
*) a
;
1654 const temp_attr
*const r
= (const temp_attr
*) b
;
1656 /* Reversed because we want a descending order sort below. */
1657 return r
->slots
- l
->slots
;
1661 unsigned num_attr
= 0;
1663 foreach_list(node
, sh
->ir
) {
1664 ir_variable
*const var
= ((ir_instruction
*) node
)->as_variable();
1666 if ((var
== NULL
) || (var
->data
.mode
!= (unsigned) direction
))
1669 if (var
->data
.explicit_location
) {
1670 if ((var
->data
.location
>= (int)(max_index
+ generic_base
))
1671 || (var
->data
.location
< 0)) {
1673 "invalid explicit location %d specified for `%s'\n",
1674 (var
->data
.location
< 0)
1675 ? var
->data
.location
1676 : var
->data
.location
- generic_base
,
1680 } else if (target_index
== MESA_SHADER_VERTEX
) {
1683 if (prog
->AttributeBindings
->get(binding
, var
->name
)) {
1684 assert(binding
>= VERT_ATTRIB_GENERIC0
);
1685 var
->data
.location
= binding
;
1686 var
->data
.is_unmatched_generic_inout
= 0;
1688 } else if (target_index
== MESA_SHADER_FRAGMENT
) {
1692 if (prog
->FragDataBindings
->get(binding
, var
->name
)) {
1693 assert(binding
>= FRAG_RESULT_DATA0
);
1694 var
->data
.location
= binding
;
1695 var
->data
.is_unmatched_generic_inout
= 0;
1697 if (prog
->FragDataIndexBindings
->get(index
, var
->name
)) {
1698 var
->data
.index
= index
;
1703 /* If the variable is not a built-in and has a location statically
1704 * assigned in the shader (presumably via a layout qualifier), make sure
1705 * that it doesn't collide with other assigned locations. Otherwise,
1706 * add it to the list of variables that need linker-assigned locations.
1708 const unsigned slots
= var
->type
->count_attribute_slots();
1709 if (var
->data
.location
!= -1) {
1710 if (var
->data
.location
>= generic_base
&& var
->data
.index
< 1) {
1711 /* From page 61 of the OpenGL 4.0 spec:
1713 * "LinkProgram will fail if the attribute bindings assigned
1714 * by BindAttribLocation do not leave not enough space to
1715 * assign a location for an active matrix attribute or an
1716 * active attribute array, both of which require multiple
1717 * contiguous generic attributes."
1719 * Previous versions of the spec contain similar language but omit
1720 * the bit about attribute arrays.
1722 * Page 61 of the OpenGL 4.0 spec also says:
1724 * "It is possible for an application to bind more than one
1725 * attribute name to the same location. This is referred to as
1726 * aliasing. This will only work if only one of the aliased
1727 * attributes is active in the executable program, or if no
1728 * path through the shader consumes more than one attribute of
1729 * a set of attributes aliased to the same location. A link
1730 * error can occur if the linker determines that every path
1731 * through the shader consumes multiple aliased attributes,
1732 * but implementations are not required to generate an error
1735 * These two paragraphs are either somewhat contradictory, or I
1736 * don't fully understand one or both of them.
1738 /* FINISHME: The code as currently written does not support
1739 * FINISHME: attribute location aliasing (see comment above).
1741 /* Mask representing the contiguous slots that will be used by
1744 const unsigned attr
= var
->data
.location
- generic_base
;
1745 const unsigned use_mask
= (1 << slots
) - 1;
1747 /* Generate a link error if the set of bits requested for this
1748 * attribute overlaps any previously allocated bits.
1750 if ((~(use_mask
<< attr
) & used_locations
) != used_locations
) {
1751 const char *const string
= (target_index
== MESA_SHADER_VERTEX
)
1752 ? "vertex shader input" : "fragment shader output";
1754 "insufficient contiguous locations "
1755 "available for %s `%s' %d %d %d", string
,
1756 var
->name
, used_locations
, use_mask
, attr
);
1760 used_locations
|= (use_mask
<< attr
);
1766 to_assign
[num_attr
].slots
= slots
;
1767 to_assign
[num_attr
].var
= var
;
1771 /* If all of the attributes were assigned locations by the application (or
1772 * are built-in attributes with fixed locations), return early. This should
1773 * be the common case.
1778 qsort(to_assign
, num_attr
, sizeof(to_assign
[0]), temp_attr::compare
);
1780 if (target_index
== MESA_SHADER_VERTEX
) {
1781 /* VERT_ATTRIB_GENERIC0 is a pseudo-alias for VERT_ATTRIB_POS. It can
1782 * only be explicitly assigned by via glBindAttribLocation. Mark it as
1783 * reserved to prevent it from being automatically allocated below.
1785 find_deref_visitor
find("gl_Vertex");
1787 if (find
.variable_found())
1788 used_locations
|= (1 << 0);
1791 for (unsigned i
= 0; i
< num_attr
; i
++) {
1792 /* Mask representing the contiguous slots that will be used by this
1795 const unsigned use_mask
= (1 << to_assign
[i
].slots
) - 1;
1797 int location
= find_available_slots(used_locations
, to_assign
[i
].slots
);
1800 const char *const string
= (target_index
== MESA_SHADER_VERTEX
)
1801 ? "vertex shader input" : "fragment shader output";
1804 "insufficient contiguous locations "
1805 "available for %s `%s'",
1806 string
, to_assign
[i
].var
->name
);
1810 to_assign
[i
].var
->data
.location
= generic_base
+ location
;
1811 to_assign
[i
].var
->data
.is_unmatched_generic_inout
= 0;
1812 used_locations
|= (use_mask
<< location
);
1820 * Demote shader inputs and outputs that are not used in other stages
1823 demote_shader_inputs_and_outputs(gl_shader
*sh
, enum ir_variable_mode mode
)
1825 foreach_list(node
, sh
->ir
) {
1826 ir_variable
*const var
= ((ir_instruction
*) node
)->as_variable();
1828 if ((var
== NULL
) || (var
->data
.mode
!= int(mode
)))
1831 /* A shader 'in' or 'out' variable is only really an input or output if
1832 * its value is used by other shader stages. This will cause the variable
1833 * to have a location assigned.
1835 if (var
->data
.is_unmatched_generic_inout
) {
1836 var
->data
.mode
= ir_var_auto
;
1843 * Store the gl_FragDepth layout in the gl_shader_program struct.
1846 store_fragdepth_layout(struct gl_shader_program
*prog
)
1848 if (prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
] == NULL
) {
1852 struct exec_list
*ir
= prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
]->ir
;
1854 /* We don't look up the gl_FragDepth symbol directly because if
1855 * gl_FragDepth is not used in the shader, it's removed from the IR.
1856 * However, the symbol won't be removed from the symbol table.
1858 * We're only interested in the cases where the variable is NOT removed
1861 foreach_list(node
, ir
) {
1862 ir_variable
*const var
= ((ir_instruction
*) node
)->as_variable();
1864 if (var
== NULL
|| var
->data
.mode
!= ir_var_shader_out
) {
1868 if (strcmp(var
->name
, "gl_FragDepth") == 0) {
1869 switch (var
->data
.depth_layout
) {
1870 case ir_depth_layout_none
:
1871 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_NONE
;
1873 case ir_depth_layout_any
:
1874 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_ANY
;
1876 case ir_depth_layout_greater
:
1877 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_GREATER
;
1879 case ir_depth_layout_less
:
1880 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_LESS
;
1882 case ir_depth_layout_unchanged
:
1883 prog
->FragDepthLayout
= FRAG_DEPTH_LAYOUT_UNCHANGED
;
1894 * Validate the resources used by a program versus the implementation limits
1897 check_resources(struct gl_context
*ctx
, struct gl_shader_program
*prog
)
1899 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
1900 struct gl_shader
*sh
= prog
->_LinkedShaders
[i
];
1905 if (sh
->num_samplers
> ctx
->Const
.Program
[i
].MaxTextureImageUnits
) {
1906 linker_error(prog
, "Too many %s shader texture samplers",
1907 _mesa_shader_stage_to_string(i
));
1910 if (sh
->num_uniform_components
>
1911 ctx
->Const
.Program
[i
].MaxUniformComponents
) {
1912 if (ctx
->Const
.GLSLSkipStrictMaxUniformLimitCheck
) {
1913 linker_warning(prog
, "Too many %s shader default uniform block "
1914 "components, but the driver will try to optimize "
1915 "them out; this is non-portable out-of-spec "
1917 _mesa_shader_stage_to_string(i
));
1919 linker_error(prog
, "Too many %s shader default uniform block "
1921 _mesa_shader_stage_to_string(i
));
1925 if (sh
->num_combined_uniform_components
>
1926 ctx
->Const
.Program
[i
].MaxCombinedUniformComponents
) {
1927 if (ctx
->Const
.GLSLSkipStrictMaxUniformLimitCheck
) {
1928 linker_warning(prog
, "Too many %s shader uniform components, "
1929 "but the driver will try to optimize them out; "
1930 "this is non-portable out-of-spec behavior\n",
1931 _mesa_shader_stage_to_string(i
));
1933 linker_error(prog
, "Too many %s shader uniform components",
1934 _mesa_shader_stage_to_string(i
));
1939 unsigned blocks
[MESA_SHADER_STAGES
] = {0};
1940 unsigned total_uniform_blocks
= 0;
1942 for (unsigned i
= 0; i
< prog
->NumUniformBlocks
; i
++) {
1943 for (unsigned j
= 0; j
< MESA_SHADER_STAGES
; j
++) {
1944 if (prog
->UniformBlockStageIndex
[j
][i
] != -1) {
1946 total_uniform_blocks
++;
1950 if (total_uniform_blocks
> ctx
->Const
.MaxCombinedUniformBlocks
) {
1951 linker_error(prog
, "Too many combined uniform blocks (%d/%d)",
1952 prog
->NumUniformBlocks
,
1953 ctx
->Const
.MaxCombinedUniformBlocks
);
1955 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
1956 const unsigned max_uniform_blocks
=
1957 ctx
->Const
.Program
[i
].MaxUniformBlocks
;
1958 if (blocks
[i
] > max_uniform_blocks
) {
1959 linker_error(prog
, "Too many %s uniform blocks (%d/%d)",
1960 _mesa_shader_stage_to_string(i
),
1962 max_uniform_blocks
);
1971 link_shaders(struct gl_context
*ctx
, struct gl_shader_program
*prog
)
1973 tfeedback_decl
*tfeedback_decls
= NULL
;
1974 unsigned num_tfeedback_decls
= prog
->TransformFeedback
.NumVarying
;
1976 void *mem_ctx
= ralloc_context(NULL
); // temporary linker context
1978 prog
->LinkStatus
= true; /* All error paths will set this to false */
1979 prog
->Validated
= false;
1980 prog
->_Used
= false;
1982 ralloc_free(prog
->InfoLog
);
1983 prog
->InfoLog
= ralloc_strdup(NULL
, "");
1985 ralloc_free(prog
->UniformBlocks
);
1986 prog
->UniformBlocks
= NULL
;
1987 prog
->NumUniformBlocks
= 0;
1988 for (int i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
1989 ralloc_free(prog
->UniformBlockStageIndex
[i
]);
1990 prog
->UniformBlockStageIndex
[i
] = NULL
;
1993 ralloc_free(prog
->AtomicBuffers
);
1994 prog
->AtomicBuffers
= NULL
;
1995 prog
->NumAtomicBuffers
= 0;
1997 /* Separate the shaders into groups based on their type.
1999 struct gl_shader
**shader_list
[MESA_SHADER_STAGES
];
2000 unsigned num_shaders
[MESA_SHADER_STAGES
];
2002 for (int i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2003 shader_list
[i
] = (struct gl_shader
**)
2004 calloc(prog
->NumShaders
, sizeof(struct gl_shader
*));
2008 unsigned min_version
= UINT_MAX
;
2009 unsigned max_version
= 0;
2010 const bool is_es_prog
=
2011 (prog
->NumShaders
> 0 && prog
->Shaders
[0]->IsES
) ? true : false;
2012 for (unsigned i
= 0; i
< prog
->NumShaders
; i
++) {
2013 min_version
= MIN2(min_version
, prog
->Shaders
[i
]->Version
);
2014 max_version
= MAX2(max_version
, prog
->Shaders
[i
]->Version
);
2016 if (prog
->Shaders
[i
]->IsES
!= is_es_prog
) {
2017 linker_error(prog
, "all shaders must use same shading "
2018 "language version\n");
2022 gl_shader_stage shader_type
= prog
->Shaders
[i
]->Stage
;
2023 shader_list
[shader_type
][num_shaders
[shader_type
]] = prog
->Shaders
[i
];
2024 num_shaders
[shader_type
]++;
2027 /* In desktop GLSL, different shader versions may be linked together. In
2028 * GLSL ES, all shader versions must be the same.
2030 if (is_es_prog
&& min_version
!= max_version
) {
2031 linker_error(prog
, "all shaders must use same shading "
2032 "language version\n");
2036 prog
->Version
= max_version
;
2037 prog
->IsES
= is_es_prog
;
2039 /* Geometry shaders have to be linked with vertex shaders.
2041 if (num_shaders
[MESA_SHADER_GEOMETRY
] > 0 &&
2042 num_shaders
[MESA_SHADER_VERTEX
] == 0) {
2043 linker_error(prog
, "Geometry shader must be linked with "
2048 for (unsigned int i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2049 if (prog
->_LinkedShaders
[i
] != NULL
)
2050 ctx
->Driver
.DeleteShader(ctx
, prog
->_LinkedShaders
[i
]);
2052 prog
->_LinkedShaders
[i
] = NULL
;
2055 /* Link all shaders for a particular stage and validate the result.
2057 for (int stage
= 0; stage
< MESA_SHADER_STAGES
; stage
++) {
2058 if (num_shaders
[stage
] > 0) {
2059 gl_shader
*const sh
=
2060 link_intrastage_shaders(mem_ctx
, ctx
, prog
, shader_list
[stage
],
2061 num_shaders
[stage
]);
2063 if (!prog
->LinkStatus
)
2067 case MESA_SHADER_VERTEX
:
2068 validate_vertex_shader_executable(prog
, sh
);
2070 case MESA_SHADER_GEOMETRY
:
2071 validate_geometry_shader_executable(prog
, sh
);
2073 case MESA_SHADER_FRAGMENT
:
2074 validate_fragment_shader_executable(prog
, sh
);
2077 if (!prog
->LinkStatus
)
2080 _mesa_reference_shader(ctx
, &prog
->_LinkedShaders
[stage
], sh
);
2084 if (num_shaders
[MESA_SHADER_GEOMETRY
] > 0)
2085 prog
->LastClipDistanceArraySize
= prog
->Geom
.ClipDistanceArraySize
;
2086 else if (num_shaders
[MESA_SHADER_VERTEX
] > 0)
2087 prog
->LastClipDistanceArraySize
= prog
->Vert
.ClipDistanceArraySize
;
2089 prog
->LastClipDistanceArraySize
= 0; /* Not used */
2091 /* Here begins the inter-stage linking phase. Some initial validation is
2092 * performed, then locations are assigned for uniforms, attributes, and
2095 cross_validate_uniforms(prog
);
2096 if (!prog
->LinkStatus
)
2101 for (prev
= 0; prev
< MESA_SHADER_STAGES
; prev
++) {
2102 if (prog
->_LinkedShaders
[prev
] != NULL
)
2106 /* Validate the inputs of each stage with the output of the preceding
2109 for (unsigned i
= prev
+ 1; i
< MESA_SHADER_STAGES
; i
++) {
2110 if (prog
->_LinkedShaders
[i
] == NULL
)
2113 validate_interstage_inout_blocks(prog
, prog
->_LinkedShaders
[prev
],
2114 prog
->_LinkedShaders
[i
]);
2115 if (!prog
->LinkStatus
)
2118 cross_validate_outputs_to_inputs(prog
,
2119 prog
->_LinkedShaders
[prev
],
2120 prog
->_LinkedShaders
[i
]);
2121 if (!prog
->LinkStatus
)
2127 /* Cross-validate uniform blocks between shader stages */
2128 validate_interstage_uniform_blocks(prog
, prog
->_LinkedShaders
,
2129 MESA_SHADER_STAGES
);
2130 if (!prog
->LinkStatus
)
2133 for (unsigned int i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2134 if (prog
->_LinkedShaders
[i
] != NULL
)
2135 lower_named_interface_blocks(mem_ctx
, prog
->_LinkedShaders
[i
]);
2138 /* Implement the GLSL 1.30+ rule for discard vs infinite loops Do
2139 * it before optimization because we want most of the checks to get
2140 * dropped thanks to constant propagation.
2142 * This rule also applies to GLSL ES 3.00.
2144 if (max_version
>= (is_es_prog
? 300 : 130)) {
2145 struct gl_shader
*sh
= prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
];
2147 lower_discard_flow(sh
->ir
);
2151 if (!interstage_cross_validate_uniform_blocks(prog
))
2154 /* Do common optimization before assigning storage for attributes,
2155 * uniforms, and varyings. Later optimization could possibly make
2156 * some of that unused.
2158 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2159 if (prog
->_LinkedShaders
[i
] == NULL
)
2162 detect_recursion_linked(prog
, prog
->_LinkedShaders
[i
]->ir
);
2163 if (!prog
->LinkStatus
)
2166 if (ctx
->ShaderCompilerOptions
[i
].LowerClipDistance
) {
2167 lower_clip_distance(prog
->_LinkedShaders
[i
]);
2170 unsigned max_unroll
= ctx
->ShaderCompilerOptions
[i
].MaxUnrollIterations
;
2172 while (do_common_optimization(prog
->_LinkedShaders
[i
]->ir
, true, false, max_unroll
, &ctx
->ShaderCompilerOptions
[i
]))
2176 /* Mark all generic shader inputs and outputs as unpaired. */
2177 if (prog
->_LinkedShaders
[MESA_SHADER_VERTEX
] != NULL
) {
2178 link_invalidate_variable_locations(
2179 prog
->_LinkedShaders
[MESA_SHADER_VERTEX
]->ir
);
2181 if (prog
->_LinkedShaders
[MESA_SHADER_GEOMETRY
] != NULL
) {
2182 link_invalidate_variable_locations(
2183 prog
->_LinkedShaders
[MESA_SHADER_GEOMETRY
]->ir
);
2185 if (prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
] != NULL
) {
2186 link_invalidate_variable_locations(
2187 prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
]->ir
);
2190 /* FINISHME: The value of the max_attribute_index parameter is
2191 * FINISHME: implementation dependent based on the value of
2192 * FINISHME: GL_MAX_VERTEX_ATTRIBS. GL_MAX_VERTEX_ATTRIBS must be
2193 * FINISHME: at least 16, so hardcode 16 for now.
2195 if (!assign_attribute_or_color_locations(prog
, MESA_SHADER_VERTEX
, 16)) {
2199 if (!assign_attribute_or_color_locations(prog
, MESA_SHADER_FRAGMENT
, MAX2(ctx
->Const
.MaxDrawBuffers
, ctx
->Const
.MaxDualSourceDrawBuffers
))) {
2204 for (first
= 0; first
< MESA_SHADER_STAGES
; first
++) {
2205 if (prog
->_LinkedShaders
[first
] != NULL
)
2209 if (num_tfeedback_decls
!= 0) {
2210 /* From GL_EXT_transform_feedback:
2211 * A program will fail to link if:
2213 * * the <count> specified by TransformFeedbackVaryingsEXT is
2214 * non-zero, but the program object has no vertex or geometry
2217 if (first
== MESA_SHADER_FRAGMENT
) {
2218 linker_error(prog
, "Transform feedback varyings specified, but "
2219 "no vertex or geometry shader is present.");
2223 tfeedback_decls
= ralloc_array(mem_ctx
, tfeedback_decl
,
2224 prog
->TransformFeedback
.NumVarying
);
2225 if (!parse_tfeedback_decls(ctx
, prog
, mem_ctx
, num_tfeedback_decls
,
2226 prog
->TransformFeedback
.VaryingNames
,
2231 /* Linking the stages in the opposite order (from fragment to vertex)
2232 * ensures that inter-shader outputs written to in an earlier stage are
2233 * eliminated if they are (transitively) not used in a later stage.
2236 for (last
= MESA_SHADER_STAGES
-1; last
>= 0; last
--) {
2237 if (prog
->_LinkedShaders
[last
] != NULL
)
2241 if (last
>= 0 && last
< MESA_SHADER_FRAGMENT
) {
2242 gl_shader
*const sh
= prog
->_LinkedShaders
[last
];
2244 if (num_tfeedback_decls
!= 0) {
2245 /* There was no fragment shader, but we still have to assign varying
2246 * locations for use by transform feedback.
2248 if (!assign_varying_locations(ctx
, mem_ctx
, prog
,
2250 num_tfeedback_decls
, tfeedback_decls
,
2255 do_dead_builtin_varyings(ctx
, sh
, NULL
,
2256 num_tfeedback_decls
, tfeedback_decls
);
2258 demote_shader_inputs_and_outputs(sh
, ir_var_shader_out
);
2260 /* Eliminate code that is now dead due to unused outputs being demoted.
2262 while (do_dead_code(sh
->ir
, false))
2265 else if (first
== MESA_SHADER_FRAGMENT
) {
2266 /* If the program only contains a fragment shader...
2268 gl_shader
*const sh
= prog
->_LinkedShaders
[first
];
2270 do_dead_builtin_varyings(ctx
, NULL
, sh
,
2271 num_tfeedback_decls
, tfeedback_decls
);
2273 demote_shader_inputs_and_outputs(sh
, ir_var_shader_in
);
2275 while (do_dead_code(sh
->ir
, false))
2280 for (int i
= next
- 1; i
>= 0; i
--) {
2281 if (prog
->_LinkedShaders
[i
] == NULL
)
2284 gl_shader
*const sh_i
= prog
->_LinkedShaders
[i
];
2285 gl_shader
*const sh_next
= prog
->_LinkedShaders
[next
];
2286 unsigned gs_input_vertices
=
2287 next
== MESA_SHADER_GEOMETRY
? prog
->Geom
.VerticesIn
: 0;
2289 if (!assign_varying_locations(ctx
, mem_ctx
, prog
, sh_i
, sh_next
,
2290 next
== MESA_SHADER_FRAGMENT
? num_tfeedback_decls
: 0,
2291 tfeedback_decls
, gs_input_vertices
))
2294 do_dead_builtin_varyings(ctx
, sh_i
, sh_next
,
2295 next
== MESA_SHADER_FRAGMENT
? num_tfeedback_decls
: 0,
2298 demote_shader_inputs_and_outputs(sh_i
, ir_var_shader_out
);
2299 demote_shader_inputs_and_outputs(sh_next
, ir_var_shader_in
);
2301 /* Eliminate code that is now dead due to unused outputs being demoted.
2303 while (do_dead_code(sh_i
->ir
, false))
2305 while (do_dead_code(sh_next
->ir
, false))
2308 /* This must be done after all dead varyings are eliminated. */
2309 if (!check_against_output_limit(ctx
, prog
, sh_i
))
2311 if (!check_against_input_limit(ctx
, prog
, sh_next
))
2317 if (!store_tfeedback_info(ctx
, prog
, num_tfeedback_decls
, tfeedback_decls
))
2320 update_array_sizes(prog
);
2321 link_assign_uniform_locations(prog
);
2322 link_assign_atomic_counter_resources(ctx
, prog
);
2323 store_fragdepth_layout(prog
);
2325 check_resources(ctx
, prog
);
2326 link_check_atomic_counter_resources(ctx
, prog
);
2328 if (!prog
->LinkStatus
)
2331 /* OpenGL ES requires that a vertex shader and a fragment shader both be
2332 * present in a linked program. By checking prog->IsES, we also
2333 * catch the GL_ARB_ES2_compatibility case.
2335 if (!prog
->InternalSeparateShader
&&
2336 (ctx
->API
== API_OPENGLES2
|| prog
->IsES
)) {
2337 if (prog
->_LinkedShaders
[MESA_SHADER_VERTEX
] == NULL
) {
2338 linker_error(prog
, "program lacks a vertex shader\n");
2339 } else if (prog
->_LinkedShaders
[MESA_SHADER_FRAGMENT
] == NULL
) {
2340 linker_error(prog
, "program lacks a fragment shader\n");
2344 /* FINISHME: Assign fragment shader output locations. */
2347 for (unsigned i
= 0; i
< MESA_SHADER_STAGES
; i
++) {
2348 free(shader_list
[i
]);
2349 if (prog
->_LinkedShaders
[i
] == NULL
)
2352 /* Do a final validation step to make sure that the IR wasn't
2353 * invalidated by any modifications performed after intrastage linking.
2355 validate_ir_tree(prog
->_LinkedShaders
[i
]->ir
);
2357 /* Retain any live IR, but trash the rest. */
2358 reparent_ir(prog
->_LinkedShaders
[i
]->ir
, prog
->_LinkedShaders
[i
]->ir
);
2360 /* The symbol table in the linked shaders may contain references to
2361 * variables that were removed (e.g., unused uniforms). Since it may
2362 * contain junk, there is no possible valid use. Delete it and set the
2365 delete prog
->_LinkedShaders
[i
]->symbols
;
2366 prog
->_LinkedShaders
[i
]->symbols
= NULL
;
2369 ralloc_free(mem_ctx
);