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16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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21 * DEALINGS IN THE SOFTWARE.
25 * \file link_varyings.cpp
27 * Linker functions related specifically to linking varyings between shader
32 #include "main/mtypes.h"
33 #include "glsl_symbol_table.h"
34 #include "glsl_parser_extras.h"
35 #include "ir_optimization.h"
37 #include "link_varyings.h"
38 #include "main/macros.h"
39 #include "program/hash_table.h"
44 * Validate the types and qualifiers of an output from one stage against the
45 * matching input to another stage.
48 cross_validate_types_and_qualifiers(struct gl_shader_program
*prog
,
49 const ir_variable
*input
,
50 const ir_variable
*output
,
51 gl_shader_stage consumer_stage
,
52 gl_shader_stage producer_stage
)
54 /* Check that the types match between stages.
56 const glsl_type
*type_to_match
= input
->type
;
58 /* VS -> GS, VS -> TCS, VS -> TES, TES -> GS */
59 const bool extra_array_level
= (producer_stage
== MESA_SHADER_VERTEX
&&
60 consumer_stage
!= MESA_SHADER_FRAGMENT
) ||
61 consumer_stage
== MESA_SHADER_GEOMETRY
;
62 if (extra_array_level
) {
63 assert(type_to_match
->is_array());
64 type_to_match
= type_to_match
->fields
.array
;
67 if (type_to_match
!= output
->type
) {
68 /* There is a bit of a special case for gl_TexCoord. This
69 * built-in is unsized by default. Applications that variable
70 * access it must redeclare it with a size. There is some
71 * language in the GLSL spec that implies the fragment shader
72 * and vertex shader do not have to agree on this size. Other
73 * driver behave this way, and one or two applications seem to
76 * Neither declaration needs to be modified here because the array
77 * sizes are fixed later when update_array_sizes is called.
79 * From page 48 (page 54 of the PDF) of the GLSL 1.10 spec:
81 * "Unlike user-defined varying variables, the built-in
82 * varying variables don't have a strict one-to-one
83 * correspondence between the vertex language and the
86 if (!output
->type
->is_array() || !is_gl_identifier(output
->name
)) {
88 "%s shader output `%s' declared as type `%s', "
89 "but %s shader input declared as type `%s'\n",
90 _mesa_shader_stage_to_string(producer_stage
),
93 _mesa_shader_stage_to_string(consumer_stage
),
99 /* Check that all of the qualifiers match between stages.
101 if (input
->data
.centroid
!= output
->data
.centroid
) {
103 "%s shader output `%s' %s centroid qualifier, "
104 "but %s shader input %s centroid qualifier\n",
105 _mesa_shader_stage_to_string(producer_stage
),
107 (output
->data
.centroid
) ? "has" : "lacks",
108 _mesa_shader_stage_to_string(consumer_stage
),
109 (input
->data
.centroid
) ? "has" : "lacks");
113 if (input
->data
.sample
!= output
->data
.sample
) {
115 "%s shader output `%s' %s sample qualifier, "
116 "but %s shader input %s sample qualifier\n",
117 _mesa_shader_stage_to_string(producer_stage
),
119 (output
->data
.sample
) ? "has" : "lacks",
120 _mesa_shader_stage_to_string(consumer_stage
),
121 (input
->data
.sample
) ? "has" : "lacks");
125 if (input
->data
.patch
!= output
->data
.patch
) {
127 "%s shader output `%s' %s patch qualifier, "
128 "but %s shader input %s patch qualifier\n",
129 _mesa_shader_stage_to_string(producer_stage
),
131 (output
->data
.patch
) ? "has" : "lacks",
132 _mesa_shader_stage_to_string(consumer_stage
),
133 (input
->data
.patch
) ? "has" : "lacks");
137 if (!prog
->IsES
&& input
->data
.invariant
!= output
->data
.invariant
) {
139 "%s shader output `%s' %s invariant qualifier, "
140 "but %s shader input %s invariant qualifier\n",
141 _mesa_shader_stage_to_string(producer_stage
),
143 (output
->data
.invariant
) ? "has" : "lacks",
144 _mesa_shader_stage_to_string(consumer_stage
),
145 (input
->data
.invariant
) ? "has" : "lacks");
149 /* GLSL >= 4.40 removes text requiring interpolation qualifiers
150 * to match cross stage, they must only match within the same stage.
152 * From page 84 (page 90 of the PDF) of the GLSL 4.40 spec:
154 * "It is a link-time error if, within the same stage, the interpolation
155 * qualifiers of variables of the same name do not match.
158 if (input
->data
.interpolation
!= output
->data
.interpolation
&&
159 prog
->Version
< 440) {
161 "%s shader output `%s' specifies %s "
162 "interpolation qualifier, "
163 "but %s shader input specifies %s "
164 "interpolation qualifier\n",
165 _mesa_shader_stage_to_string(producer_stage
),
167 interpolation_string(output
->data
.interpolation
),
168 _mesa_shader_stage_to_string(consumer_stage
),
169 interpolation_string(input
->data
.interpolation
));
175 * Validate front and back color outputs against single color input
178 cross_validate_front_and_back_color(struct gl_shader_program
*prog
,
179 const ir_variable
*input
,
180 const ir_variable
*front_color
,
181 const ir_variable
*back_color
,
182 gl_shader_stage consumer_stage
,
183 gl_shader_stage producer_stage
)
185 if (front_color
!= NULL
&& front_color
->data
.assigned
)
186 cross_validate_types_and_qualifiers(prog
, input
, front_color
,
187 consumer_stage
, producer_stage
);
189 if (back_color
!= NULL
&& back_color
->data
.assigned
)
190 cross_validate_types_and_qualifiers(prog
, input
, back_color
,
191 consumer_stage
, producer_stage
);
195 * Validate that outputs from one stage match inputs of another
198 cross_validate_outputs_to_inputs(struct gl_shader_program
*prog
,
199 gl_shader
*producer
, gl_shader
*consumer
)
201 glsl_symbol_table parameters
;
202 ir_variable
*explicit_locations
[MAX_VARYING
] = { NULL
, };
204 /* Find all shader outputs in the "producer" stage.
206 foreach_in_list(ir_instruction
, node
, producer
->ir
) {
207 ir_variable
*const var
= node
->as_variable();
209 if ((var
== NULL
) || (var
->data
.mode
!= ir_var_shader_out
))
212 if (!var
->data
.explicit_location
213 || var
->data
.location
< VARYING_SLOT_VAR0
)
214 parameters
.add_variable(var
);
216 /* User-defined varyings with explicit locations are handled
217 * differently because they do not need to have matching names.
219 const unsigned idx
= var
->data
.location
- VARYING_SLOT_VAR0
;
221 if (explicit_locations
[idx
] != NULL
) {
223 "%s shader has multiple outputs explicitly "
224 "assigned to location %d\n",
225 _mesa_shader_stage_to_string(producer
->Stage
),
230 explicit_locations
[idx
] = var
;
235 /* Find all shader inputs in the "consumer" stage. Any variables that have
236 * matching outputs already in the symbol table must have the same type and
239 * Exception: if the consumer is the geometry shader, then the inputs
240 * should be arrays and the type of the array element should match the type
241 * of the corresponding producer output.
243 foreach_in_list(ir_instruction
, node
, consumer
->ir
) {
244 ir_variable
*const input
= node
->as_variable();
246 if ((input
== NULL
) || (input
->data
.mode
!= ir_var_shader_in
))
249 if (strcmp(input
->name
, "gl_Color") == 0 && input
->data
.used
) {
250 const ir_variable
*const front_color
=
251 parameters
.get_variable("gl_FrontColor");
253 const ir_variable
*const back_color
=
254 parameters
.get_variable("gl_BackColor");
256 cross_validate_front_and_back_color(prog
, input
,
257 front_color
, back_color
,
258 consumer
->Stage
, producer
->Stage
);
259 } else if (strcmp(input
->name
, "gl_SecondaryColor") == 0 && input
->data
.used
) {
260 const ir_variable
*const front_color
=
261 parameters
.get_variable("gl_FrontSecondaryColor");
263 const ir_variable
*const back_color
=
264 parameters
.get_variable("gl_BackSecondaryColor");
266 cross_validate_front_and_back_color(prog
, input
,
267 front_color
, back_color
,
268 consumer
->Stage
, producer
->Stage
);
270 /* The rules for connecting inputs and outputs change in the presence
271 * of explicit locations. In this case, we no longer care about the
272 * names of the variables. Instead, we care only about the
273 * explicitly assigned location.
275 ir_variable
*output
= NULL
;
276 if (input
->data
.explicit_location
277 && input
->data
.location
>= VARYING_SLOT_VAR0
) {
278 output
= explicit_locations
[input
->data
.location
- VARYING_SLOT_VAR0
];
280 if (output
== NULL
) {
282 "%s shader input `%s' with explicit location "
283 "has no matching output\n",
284 _mesa_shader_stage_to_string(consumer
->Stage
),
288 output
= parameters
.get_variable(input
->name
);
291 if (output
!= NULL
) {
292 cross_validate_types_and_qualifiers(prog
, input
, output
,
293 consumer
->Stage
, producer
->Stage
);
295 /* Check for input vars with unmatched output vars in prev stage
296 * taking into account that interface blocks could have a matching
297 * output but with different name, so we ignore them.
299 assert(!input
->data
.assigned
);
300 if (input
->data
.used
&& !input
->get_interface_type() &&
301 !input
->data
.explicit_location
&& !prog
->SeparateShader
)
303 "%s shader input `%s' "
304 "has no matching output in the previous stage\n",
305 _mesa_shader_stage_to_string(consumer
->Stage
),
314 * Initialize this object based on a string that was passed to
315 * glTransformFeedbackVaryings.
317 * If the input is mal-formed, this call still succeeds, but it sets
318 * this->var_name to a mal-formed input, so tfeedback_decl::find_output_var()
319 * will fail to find any matching variable.
322 tfeedback_decl::init(struct gl_context
*ctx
, const void *mem_ctx
,
325 /* We don't have to be pedantic about what is a valid GLSL variable name,
326 * because any variable with an invalid name can't exist in the IR anyway.
330 this->orig_name
= input
;
331 this->is_clip_distance_mesa
= false;
332 this->skip_components
= 0;
333 this->next_buffer_separator
= false;
334 this->matched_candidate
= NULL
;
337 if (ctx
->Extensions
.ARB_transform_feedback3
) {
338 /* Parse gl_NextBuffer. */
339 if (strcmp(input
, "gl_NextBuffer") == 0) {
340 this->next_buffer_separator
= true;
344 /* Parse gl_SkipComponents. */
345 if (strcmp(input
, "gl_SkipComponents1") == 0)
346 this->skip_components
= 1;
347 else if (strcmp(input
, "gl_SkipComponents2") == 0)
348 this->skip_components
= 2;
349 else if (strcmp(input
, "gl_SkipComponents3") == 0)
350 this->skip_components
= 3;
351 else if (strcmp(input
, "gl_SkipComponents4") == 0)
352 this->skip_components
= 4;
354 if (this->skip_components
)
358 /* Parse a declaration. */
359 const char *base_name_end
;
360 long subscript
= parse_program_resource_name(input
, &base_name_end
);
361 this->var_name
= ralloc_strndup(mem_ctx
, input
, base_name_end
- input
);
362 if (this->var_name
== NULL
) {
363 _mesa_error_no_memory(__func__
);
367 if (subscript
>= 0) {
368 this->array_subscript
= subscript
;
369 this->is_subscripted
= true;
371 this->is_subscripted
= false;
374 /* For drivers that lower gl_ClipDistance to gl_ClipDistanceMESA, this
375 * class must behave specially to account for the fact that gl_ClipDistance
376 * is converted from a float[8] to a vec4[2].
378 if (ctx
->Const
.ShaderCompilerOptions
[MESA_SHADER_VERTEX
].LowerClipDistance
&&
379 strcmp(this->var_name
, "gl_ClipDistance") == 0) {
380 this->is_clip_distance_mesa
= true;
386 * Determine whether two tfeedback_decl objects refer to the same variable and
387 * array index (if applicable).
390 tfeedback_decl::is_same(const tfeedback_decl
&x
, const tfeedback_decl
&y
)
392 assert(x
.is_varying() && y
.is_varying());
394 if (strcmp(x
.var_name
, y
.var_name
) != 0)
396 if (x
.is_subscripted
!= y
.is_subscripted
)
398 if (x
.is_subscripted
&& x
.array_subscript
!= y
.array_subscript
)
405 * Assign a location and stream ID for this tfeedback_decl object based on the
406 * transform feedback candidate found by find_candidate.
408 * If an error occurs, the error is reported through linker_error() and false
412 tfeedback_decl::assign_location(struct gl_context
*ctx
,
413 struct gl_shader_program
*prog
)
415 assert(this->is_varying());
417 unsigned fine_location
418 = this->matched_candidate
->toplevel_var
->data
.location
* 4
419 + this->matched_candidate
->toplevel_var
->data
.location_frac
420 + this->matched_candidate
->offset
;
422 if (this->matched_candidate
->type
->is_array()) {
424 const unsigned matrix_cols
=
425 this->matched_candidate
->type
->fields
.array
->matrix_columns
;
426 const unsigned vector_elements
=
427 this->matched_candidate
->type
->fields
.array
->vector_elements
;
428 unsigned actual_array_size
= this->is_clip_distance_mesa
?
429 prog
->LastClipDistanceArraySize
:
430 this->matched_candidate
->type
->array_size();
432 if (this->is_subscripted
) {
433 /* Check array bounds. */
434 if (this->array_subscript
>= actual_array_size
) {
435 linker_error(prog
, "Transform feedback varying %s has index "
436 "%i, but the array size is %u.",
437 this->orig_name
, this->array_subscript
,
441 unsigned array_elem_size
= this->is_clip_distance_mesa
?
442 1 : vector_elements
* matrix_cols
;
443 fine_location
+= array_elem_size
* this->array_subscript
;
446 this->size
= actual_array_size
;
448 this->vector_elements
= vector_elements
;
449 this->matrix_columns
= matrix_cols
;
450 if (this->is_clip_distance_mesa
)
451 this->type
= GL_FLOAT
;
453 this->type
= this->matched_candidate
->type
->fields
.array
->gl_type
;
455 /* Regular variable (scalar, vector, or matrix) */
456 if (this->is_subscripted
) {
457 linker_error(prog
, "Transform feedback varying %s requested, "
458 "but %s is not an array.",
459 this->orig_name
, this->var_name
);
463 this->vector_elements
= this->matched_candidate
->type
->vector_elements
;
464 this->matrix_columns
= this->matched_candidate
->type
->matrix_columns
;
465 this->type
= this->matched_candidate
->type
->gl_type
;
467 this->location
= fine_location
/ 4;
468 this->location_frac
= fine_location
% 4;
470 /* From GL_EXT_transform_feedback:
471 * A program will fail to link if:
473 * * the total number of components to capture in any varying
474 * variable in <varyings> is greater than the constant
475 * MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS_EXT and the
476 * buffer mode is SEPARATE_ATTRIBS_EXT;
478 if (prog
->TransformFeedback
.BufferMode
== GL_SEPARATE_ATTRIBS
&&
479 this->num_components() >
480 ctx
->Const
.MaxTransformFeedbackSeparateComponents
) {
481 linker_error(prog
, "Transform feedback varying %s exceeds "
482 "MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS.",
487 /* Only transform feedback varyings can be assigned to non-zero streams,
488 * so assign the stream id here.
490 this->stream_id
= this->matched_candidate
->toplevel_var
->data
.stream
;
497 tfeedback_decl::get_num_outputs() const
499 if (!this->is_varying()) {
503 return (this->num_components() + this->location_frac
+ 3)/4;
508 * Update gl_transform_feedback_info to reflect this tfeedback_decl.
510 * If an error occurs, the error is reported through linker_error() and false
514 tfeedback_decl::store(struct gl_context
*ctx
, struct gl_shader_program
*prog
,
515 struct gl_transform_feedback_info
*info
,
516 unsigned buffer
, const unsigned max_outputs
) const
518 assert(!this->next_buffer_separator
);
520 /* Handle gl_SkipComponents. */
521 if (this->skip_components
) {
522 info
->BufferStride
[buffer
] += this->skip_components
;
526 /* From GL_EXT_transform_feedback:
527 * A program will fail to link if:
529 * * the total number of components to capture is greater than
530 * the constant MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS_EXT
531 * and the buffer mode is INTERLEAVED_ATTRIBS_EXT.
533 if (prog
->TransformFeedback
.BufferMode
== GL_INTERLEAVED_ATTRIBS
&&
534 info
->BufferStride
[buffer
] + this->num_components() >
535 ctx
->Const
.MaxTransformFeedbackInterleavedComponents
) {
536 linker_error(prog
, "The MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS "
537 "limit has been exceeded.");
541 unsigned location
= this->location
;
542 unsigned location_frac
= this->location_frac
;
543 unsigned num_components
= this->num_components();
544 while (num_components
> 0) {
545 unsigned output_size
= MIN2(num_components
, 4 - location_frac
);
546 assert(info
->NumOutputs
< max_outputs
);
547 info
->Outputs
[info
->NumOutputs
].ComponentOffset
= location_frac
;
548 info
->Outputs
[info
->NumOutputs
].OutputRegister
= location
;
549 info
->Outputs
[info
->NumOutputs
].NumComponents
= output_size
;
550 info
->Outputs
[info
->NumOutputs
].StreamId
= stream_id
;
551 info
->Outputs
[info
->NumOutputs
].OutputBuffer
= buffer
;
552 info
->Outputs
[info
->NumOutputs
].DstOffset
= info
->BufferStride
[buffer
];
554 info
->BufferStride
[buffer
] += output_size
;
555 num_components
-= output_size
;
560 info
->Varyings
[info
->NumVarying
].Name
= ralloc_strdup(prog
, this->orig_name
);
561 info
->Varyings
[info
->NumVarying
].Type
= this->type
;
562 info
->Varyings
[info
->NumVarying
].Size
= this->size
;
569 const tfeedback_candidate
*
570 tfeedback_decl::find_candidate(gl_shader_program
*prog
,
571 hash_table
*tfeedback_candidates
)
573 const char *name
= this->is_clip_distance_mesa
574 ? "gl_ClipDistanceMESA" : this->var_name
;
575 this->matched_candidate
= (const tfeedback_candidate
*)
576 hash_table_find(tfeedback_candidates
, name
);
577 if (!this->matched_candidate
) {
578 /* From GL_EXT_transform_feedback:
579 * A program will fail to link if:
581 * * any variable name specified in the <varyings> array is not
582 * declared as an output in the geometry shader (if present) or
583 * the vertex shader (if no geometry shader is present);
585 linker_error(prog
, "Transform feedback varying %s undeclared.",
588 return this->matched_candidate
;
593 * Parse all the transform feedback declarations that were passed to
594 * glTransformFeedbackVaryings() and store them in tfeedback_decl objects.
596 * If an error occurs, the error is reported through linker_error() and false
600 parse_tfeedback_decls(struct gl_context
*ctx
, struct gl_shader_program
*prog
,
601 const void *mem_ctx
, unsigned num_names
,
602 char **varying_names
, tfeedback_decl
*decls
)
604 for (unsigned i
= 0; i
< num_names
; ++i
) {
605 decls
[i
].init(ctx
, mem_ctx
, varying_names
[i
]);
607 if (!decls
[i
].is_varying())
610 /* From GL_EXT_transform_feedback:
611 * A program will fail to link if:
613 * * any two entries in the <varyings> array specify the same varying
616 * We interpret this to mean "any two entries in the <varyings> array
617 * specify the same varying variable and array index", since transform
618 * feedback of arrays would be useless otherwise.
620 for (unsigned j
= 0; j
< i
; ++j
) {
621 if (!decls
[j
].is_varying())
624 if (tfeedback_decl::is_same(decls
[i
], decls
[j
])) {
625 linker_error(prog
, "Transform feedback varying %s specified "
626 "more than once.", varying_names
[i
]);
636 * Store transform feedback location assignments into
637 * prog->LinkedTransformFeedback based on the data stored in tfeedback_decls.
639 * If an error occurs, the error is reported through linker_error() and false
643 store_tfeedback_info(struct gl_context
*ctx
, struct gl_shader_program
*prog
,
644 unsigned num_tfeedback_decls
,
645 tfeedback_decl
*tfeedback_decls
)
647 bool separate_attribs_mode
=
648 prog
->TransformFeedback
.BufferMode
== GL_SEPARATE_ATTRIBS
;
650 ralloc_free(prog
->LinkedTransformFeedback
.Varyings
);
651 ralloc_free(prog
->LinkedTransformFeedback
.Outputs
);
653 memset(&prog
->LinkedTransformFeedback
, 0,
654 sizeof(prog
->LinkedTransformFeedback
));
656 prog
->LinkedTransformFeedback
.Varyings
=
658 struct gl_transform_feedback_varying_info
,
659 num_tfeedback_decls
);
661 unsigned num_outputs
= 0;
662 for (unsigned i
= 0; i
< num_tfeedback_decls
; ++i
)
663 num_outputs
+= tfeedback_decls
[i
].get_num_outputs();
665 prog
->LinkedTransformFeedback
.Outputs
=
667 struct gl_transform_feedback_output
,
670 unsigned num_buffers
= 0;
672 if (separate_attribs_mode
) {
673 /* GL_SEPARATE_ATTRIBS */
674 for (unsigned i
= 0; i
< num_tfeedback_decls
; ++i
) {
675 if (!tfeedback_decls
[i
].store(ctx
, prog
, &prog
->LinkedTransformFeedback
,
676 num_buffers
, num_outputs
))
683 /* GL_INVERLEAVED_ATTRIBS */
684 int buffer_stream_id
= -1;
685 for (unsigned i
= 0; i
< num_tfeedback_decls
; ++i
) {
686 if (tfeedback_decls
[i
].is_next_buffer_separator()) {
688 buffer_stream_id
= -1;
690 } else if (buffer_stream_id
== -1) {
691 /* First varying writing to this buffer: remember its stream */
692 buffer_stream_id
= (int) tfeedback_decls
[i
].get_stream_id();
693 } else if (buffer_stream_id
!=
694 (int) tfeedback_decls
[i
].get_stream_id()) {
695 /* Varying writes to the same buffer from a different stream */
697 "Transform feedback can't capture varyings belonging "
698 "to different vertex streams in a single buffer. "
699 "Varying %s writes to buffer from stream %u, other "
700 "varyings in the same buffer write from stream %u.",
701 tfeedback_decls
[i
].name(),
702 tfeedback_decls
[i
].get_stream_id(),
707 if (!tfeedback_decls
[i
].store(ctx
, prog
,
708 &prog
->LinkedTransformFeedback
,
709 num_buffers
, num_outputs
))
715 assert(prog
->LinkedTransformFeedback
.NumOutputs
== num_outputs
);
717 prog
->LinkedTransformFeedback
.NumBuffers
= num_buffers
;
724 * Data structure recording the relationship between outputs of one shader
725 * stage (the "producer") and inputs of another (the "consumer").
727 class varying_matches
730 varying_matches(bool disable_varying_packing
, bool consumer_is_fs
);
732 void record(ir_variable
*producer_var
, ir_variable
*consumer_var
);
733 unsigned assign_locations();
734 void store_locations() const;
738 * If true, this driver disables varying packing, so all varyings need to
739 * be aligned on slot boundaries, and take up a number of slots equal to
740 * their number of matrix columns times their array size.
742 const bool disable_varying_packing
;
745 * Enum representing the order in which varyings are packed within a
748 * Currently we pack vec4's first, then vec2's, then scalar values, then
749 * vec3's. This order ensures that the only vectors that are at risk of
750 * having to be "double parked" (split between two adjacent varying slots)
753 enum packing_order_enum
{
756 PACKING_ORDER_SCALAR
,
760 static unsigned compute_packing_class(const ir_variable
*var
);
761 static packing_order_enum
compute_packing_order(const ir_variable
*var
);
762 static int match_comparator(const void *x_generic
, const void *y_generic
);
765 * Structure recording the relationship between a single producer output
766 * and a single consumer input.
770 * Packing class for this varying, computed by compute_packing_class().
772 unsigned packing_class
;
775 * Packing order for this varying, computed by compute_packing_order().
777 packing_order_enum packing_order
;
778 unsigned num_components
;
781 * The output variable in the producer stage.
783 ir_variable
*producer_var
;
786 * The input variable in the consumer stage.
788 ir_variable
*consumer_var
;
791 * The location which has been assigned for this varying. This is
792 * expressed in multiples of a float, with the first generic varying
793 * (i.e. the one referred to by VARYING_SLOT_VAR0) represented by the
796 unsigned generic_location
;
800 * The number of elements in the \c matches array that are currently in
803 unsigned num_matches
;
806 * The number of elements that were set aside for the \c matches array when
809 unsigned matches_capacity
;
811 const bool consumer_is_fs
;
814 } /* anonymous namespace */
816 varying_matches::varying_matches(bool disable_varying_packing
,
818 : disable_varying_packing(disable_varying_packing
),
819 consumer_is_fs(consumer_is_fs
)
821 /* Note: this initial capacity is rather arbitrarily chosen to be large
822 * enough for many cases without wasting an unreasonable amount of space.
823 * varying_matches::record() will resize the array if there are more than
824 * this number of varyings.
826 this->matches_capacity
= 8;
827 this->matches
= (match
*)
828 malloc(sizeof(*this->matches
) * this->matches_capacity
);
829 this->num_matches
= 0;
833 varying_matches::~varying_matches()
840 * Record the given producer/consumer variable pair in the list of variables
841 * that should later be assigned locations.
843 * It is permissible for \c consumer_var to be NULL (this happens if a
844 * variable is output by the producer and consumed by transform feedback, but
845 * not consumed by the consumer).
847 * If \c producer_var has already been paired up with a consumer_var, or
848 * producer_var is part of fixed pipeline functionality (and hence already has
849 * a location assigned), this function has no effect.
851 * Note: as a side effect this function may change the interpolation type of
852 * \c producer_var, but only when the change couldn't possibly affect
856 varying_matches::record(ir_variable
*producer_var
, ir_variable
*consumer_var
)
858 assert(producer_var
!= NULL
|| consumer_var
!= NULL
);
860 if ((producer_var
&& !producer_var
->data
.is_unmatched_generic_inout
)
861 || (consumer_var
&& !consumer_var
->data
.is_unmatched_generic_inout
)) {
862 /* Either a location already exists for this variable (since it is part
863 * of fixed functionality), or it has already been recorded as part of a
869 if ((consumer_var
== NULL
&& producer_var
->type
->contains_integer()) ||
871 /* Since this varying is not being consumed by the fragment shader, its
872 * interpolation type varying cannot possibly affect rendering. Also,
873 * this variable is non-flat and is (or contains) an integer.
875 * lower_packed_varyings requires all integer varyings to flat,
876 * regardless of where they appear. We can trivially satisfy that
877 * requirement by changing the interpolation type to flat here.
880 producer_var
->data
.centroid
= false;
881 producer_var
->data
.sample
= false;
882 producer_var
->data
.interpolation
= INTERP_QUALIFIER_FLAT
;
886 consumer_var
->data
.centroid
= false;
887 consumer_var
->data
.sample
= false;
888 consumer_var
->data
.interpolation
= INTERP_QUALIFIER_FLAT
;
892 if (this->num_matches
== this->matches_capacity
) {
893 this->matches_capacity
*= 2;
894 this->matches
= (match
*)
895 realloc(this->matches
,
896 sizeof(*this->matches
) * this->matches_capacity
);
899 const ir_variable
*const var
= (producer_var
!= NULL
)
900 ? producer_var
: consumer_var
;
902 this->matches
[this->num_matches
].packing_class
903 = this->compute_packing_class(var
);
904 this->matches
[this->num_matches
].packing_order
905 = this->compute_packing_order(var
);
906 if (this->disable_varying_packing
) {
907 unsigned slots
= var
->type
->is_array()
908 ? (var
->type
->length
* var
->type
->fields
.array
->matrix_columns
)
909 : var
->type
->matrix_columns
;
910 this->matches
[this->num_matches
].num_components
= 4 * slots
;
912 this->matches
[this->num_matches
].num_components
913 = var
->type
->component_slots();
915 this->matches
[this->num_matches
].producer_var
= producer_var
;
916 this->matches
[this->num_matches
].consumer_var
= consumer_var
;
919 producer_var
->data
.is_unmatched_generic_inout
= 0;
921 consumer_var
->data
.is_unmatched_generic_inout
= 0;
926 * Choose locations for all of the variable matches that were previously
927 * passed to varying_matches::record().
930 varying_matches::assign_locations()
932 /* Sort varying matches into an order that makes them easy to pack. */
933 qsort(this->matches
, this->num_matches
, sizeof(*this->matches
),
934 &varying_matches::match_comparator
);
936 unsigned generic_location
= 0;
938 for (unsigned i
= 0; i
< this->num_matches
; i
++) {
939 /* Advance to the next slot if this varying has a different packing
940 * class than the previous one, and we're not already on a slot
944 this->matches
[i
- 1].packing_class
945 != this->matches
[i
].packing_class
) {
946 generic_location
= ALIGN(generic_location
, 4);
949 this->matches
[i
].generic_location
= generic_location
;
951 generic_location
+= this->matches
[i
].num_components
;
954 return (generic_location
+ 3) / 4;
959 * Update the producer and consumer shaders to reflect the locations
960 * assignments that were made by varying_matches::assign_locations().
963 varying_matches::store_locations() const
965 for (unsigned i
= 0; i
< this->num_matches
; i
++) {
966 ir_variable
*producer_var
= this->matches
[i
].producer_var
;
967 ir_variable
*consumer_var
= this->matches
[i
].consumer_var
;
968 unsigned generic_location
= this->matches
[i
].generic_location
;
969 unsigned slot
= generic_location
/ 4;
970 unsigned offset
= generic_location
% 4;
973 producer_var
->data
.location
= VARYING_SLOT_VAR0
+ slot
;
974 producer_var
->data
.location_frac
= offset
;
978 assert(consumer_var
->data
.location
== -1);
979 consumer_var
->data
.location
= VARYING_SLOT_VAR0
+ slot
;
980 consumer_var
->data
.location_frac
= offset
;
987 * Compute the "packing class" of the given varying. This is an unsigned
988 * integer with the property that two variables in the same packing class can
989 * be safely backed into the same vec4.
992 varying_matches::compute_packing_class(const ir_variable
*var
)
994 /* Without help from the back-end, there is no way to pack together
995 * variables with different interpolation types, because
996 * lower_packed_varyings must choose exactly one interpolation type for
997 * each packed varying it creates.
999 * However, we can safely pack together floats, ints, and uints, because:
1001 * - varyings of base type "int" and "uint" must use the "flat"
1002 * interpolation type, which can only occur in GLSL 1.30 and above.
1004 * - On platforms that support GLSL 1.30 and above, lower_packed_varyings
1005 * can store flat floats as ints without losing any information (using
1006 * the ir_unop_bitcast_* opcodes).
1008 * Therefore, the packing class depends only on the interpolation type.
1010 unsigned packing_class
= var
->data
.centroid
| (var
->data
.sample
<< 1) |
1011 (var
->data
.patch
<< 2);
1013 packing_class
+= var
->data
.interpolation
;
1014 return packing_class
;
1019 * Compute the "packing order" of the given varying. This is a sort key we
1020 * use to determine when to attempt to pack the given varying relative to
1021 * other varyings in the same packing class.
1023 varying_matches::packing_order_enum
1024 varying_matches::compute_packing_order(const ir_variable
*var
)
1026 const glsl_type
*element_type
= var
->type
;
1028 while (element_type
->base_type
== GLSL_TYPE_ARRAY
) {
1029 element_type
= element_type
->fields
.array
;
1032 switch (element_type
->component_slots() % 4) {
1033 case 1: return PACKING_ORDER_SCALAR
;
1034 case 2: return PACKING_ORDER_VEC2
;
1035 case 3: return PACKING_ORDER_VEC3
;
1036 case 0: return PACKING_ORDER_VEC4
;
1038 assert(!"Unexpected value of vector_elements");
1039 return PACKING_ORDER_VEC4
;
1045 * Comparison function passed to qsort() to sort varyings by packing_class and
1046 * then by packing_order.
1049 varying_matches::match_comparator(const void *x_generic
, const void *y_generic
)
1051 const match
*x
= (const match
*) x_generic
;
1052 const match
*y
= (const match
*) y_generic
;
1054 if (x
->packing_class
!= y
->packing_class
)
1055 return x
->packing_class
- y
->packing_class
;
1056 return x
->packing_order
- y
->packing_order
;
1061 * Is the given variable a varying variable to be counted against the
1062 * limit in ctx->Const.MaxVarying?
1063 * This includes variables such as texcoords, colors and generic
1064 * varyings, but excludes variables such as gl_FrontFacing and gl_FragCoord.
1067 var_counts_against_varying_limit(gl_shader_stage stage
, const ir_variable
*var
)
1069 /* Only fragment shaders will take a varying variable as an input */
1070 if (stage
== MESA_SHADER_FRAGMENT
&&
1071 var
->data
.mode
== ir_var_shader_in
) {
1072 switch (var
->data
.location
) {
1073 case VARYING_SLOT_POS
:
1074 case VARYING_SLOT_FACE
:
1075 case VARYING_SLOT_PNTC
:
1086 * Visitor class that generates tfeedback_candidate structs describing all
1087 * possible targets of transform feedback.
1089 * tfeedback_candidate structs are stored in the hash table
1090 * tfeedback_candidates, which is passed to the constructor. This hash table
1091 * maps varying names to instances of the tfeedback_candidate struct.
1093 class tfeedback_candidate_generator
: public program_resource_visitor
1096 tfeedback_candidate_generator(void *mem_ctx
,
1097 hash_table
*tfeedback_candidates
)
1099 tfeedback_candidates(tfeedback_candidates
),
1105 void process(ir_variable
*var
)
1107 this->toplevel_var
= var
;
1108 this->varying_floats
= 0;
1109 if (var
->is_interface_instance())
1110 program_resource_visitor::process(var
->get_interface_type(),
1111 var
->get_interface_type()->name
);
1113 program_resource_visitor::process(var
);
1117 virtual void visit_field(const glsl_type
*type
, const char *name
,
1120 assert(!type
->without_array()->is_record());
1121 assert(!type
->without_array()->is_interface());
1125 tfeedback_candidate
*candidate
1126 = rzalloc(this->mem_ctx
, tfeedback_candidate
);
1127 candidate
->toplevel_var
= this->toplevel_var
;
1128 candidate
->type
= type
;
1129 candidate
->offset
= this->varying_floats
;
1130 hash_table_insert(this->tfeedback_candidates
, candidate
,
1131 ralloc_strdup(this->mem_ctx
, name
));
1132 this->varying_floats
+= type
->component_slots();
1136 * Memory context used to allocate hash table keys and values.
1138 void * const mem_ctx
;
1141 * Hash table in which tfeedback_candidate objects should be stored.
1143 hash_table
* const tfeedback_candidates
;
1146 * Pointer to the toplevel variable that is being traversed.
1148 ir_variable
*toplevel_var
;
1151 * Total number of varying floats that have been visited so far. This is
1152 * used to determine the offset to each varying within the toplevel
1155 unsigned varying_floats
;
1162 populate_consumer_input_sets(void *mem_ctx
, exec_list
*ir
,
1163 hash_table
*consumer_inputs
,
1164 hash_table
*consumer_interface_inputs
,
1165 ir_variable
*consumer_inputs_with_locations
[VARYING_SLOT_MAX
])
1167 memset(consumer_inputs_with_locations
,
1169 sizeof(consumer_inputs_with_locations
[0]) * VARYING_SLOT_MAX
);
1171 foreach_in_list(ir_instruction
, node
, ir
) {
1172 ir_variable
*const input_var
= node
->as_variable();
1174 if ((input_var
!= NULL
) && (input_var
->data
.mode
== ir_var_shader_in
)) {
1175 if (input_var
->type
->is_interface())
1178 if (input_var
->data
.explicit_location
) {
1179 /* assign_varying_locations only cares about finding the
1180 * ir_variable at the start of a contiguous location block.
1182 * - For !producer, consumer_inputs_with_locations isn't used.
1184 * - For !consumer, consumer_inputs_with_locations is empty.
1186 * For consumer && producer, if you were trying to set some
1187 * ir_variable to the middle of a location block on the other side
1188 * of producer/consumer, cross_validate_outputs_to_inputs() should
1189 * be link-erroring due to either type mismatch or location
1190 * overlaps. If the variables do match up, then they've got a
1191 * matching data.location and you only looked at
1192 * consumer_inputs_with_locations[var->data.location], not any
1193 * following entries for the array/structure.
1195 consumer_inputs_with_locations
[input_var
->data
.location
] =
1197 } else if (input_var
->get_interface_type() != NULL
) {
1198 char *const iface_field_name
=
1199 ralloc_asprintf(mem_ctx
, "%s.%s",
1200 input_var
->get_interface_type()->name
,
1202 hash_table_insert(consumer_interface_inputs
, input_var
,
1205 hash_table_insert(consumer_inputs
, input_var
,
1206 ralloc_strdup(mem_ctx
, input_var
->name
));
1215 * Find a variable from the consumer that "matches" the specified variable
1217 * This function only finds inputs with names that match. There is no
1218 * validation (here) that the types, etc. are compatible.
1221 get_matching_input(void *mem_ctx
,
1222 const ir_variable
*output_var
,
1223 hash_table
*consumer_inputs
,
1224 hash_table
*consumer_interface_inputs
,
1225 ir_variable
*consumer_inputs_with_locations
[VARYING_SLOT_MAX
])
1227 ir_variable
*input_var
;
1229 if (output_var
->data
.explicit_location
) {
1230 input_var
= consumer_inputs_with_locations
[output_var
->data
.location
];
1231 } else if (output_var
->get_interface_type() != NULL
) {
1232 char *const iface_field_name
=
1233 ralloc_asprintf(mem_ctx
, "%s.%s",
1234 output_var
->get_interface_type()->name
,
1237 (ir_variable
*) hash_table_find(consumer_interface_inputs
,
1241 (ir_variable
*) hash_table_find(consumer_inputs
, output_var
->name
);
1244 return (input_var
== NULL
|| input_var
->data
.mode
!= ir_var_shader_in
)
1251 io_variable_cmp(const void *_a
, const void *_b
)
1253 const ir_variable
*const a
= *(const ir_variable
**) _a
;
1254 const ir_variable
*const b
= *(const ir_variable
**) _b
;
1256 if (a
->data
.explicit_location
&& b
->data
.explicit_location
)
1257 return b
->data
.location
- a
->data
.location
;
1259 if (a
->data
.explicit_location
&& !b
->data
.explicit_location
)
1262 if (!a
->data
.explicit_location
&& b
->data
.explicit_location
)
1265 return -strcmp(a
->name
, b
->name
);
1269 * Sort the shader IO variables into canonical order
1272 canonicalize_shader_io(exec_list
*ir
, enum ir_variable_mode io_mode
)
1274 ir_variable
*var_table
[MAX_PROGRAM_OUTPUTS
* 4];
1275 unsigned num_variables
= 0;
1277 foreach_in_list(ir_instruction
, node
, ir
) {
1278 ir_variable
*const var
= node
->as_variable();
1280 if (var
== NULL
|| var
->data
.mode
!= io_mode
)
1283 /* If we have already encountered more I/O variables that could
1284 * successfully link, bail.
1286 if (num_variables
== ARRAY_SIZE(var_table
))
1289 var_table
[num_variables
++] = var
;
1292 if (num_variables
== 0)
1295 /* Sort the list in reverse order (io_variable_cmp handles this). Later
1296 * we're going to push the variables on to the IR list as a stack, so we
1297 * want the last variable (in canonical order) to be first in the list.
1299 qsort(var_table
, num_variables
, sizeof(var_table
[0]), io_variable_cmp
);
1301 /* Remove the variable from it's current location in the IR, and put it at
1304 for (unsigned i
= 0; i
< num_variables
; i
++) {
1305 var_table
[i
]->remove();
1306 ir
->push_head(var_table
[i
]);
1311 * Assign locations for all variables that are produced in one pipeline stage
1312 * (the "producer") and consumed in the next stage (the "consumer").
1314 * Variables produced by the producer may also be consumed by transform
1317 * \param num_tfeedback_decls is the number of declarations indicating
1318 * variables that may be consumed by transform feedback.
1320 * \param tfeedback_decls is a pointer to an array of tfeedback_decl objects
1321 * representing the result of parsing the strings passed to
1322 * glTransformFeedbackVaryings(). assign_location() will be called for
1323 * each of these objects that matches one of the outputs of the
1326 * \param gs_input_vertices: if \c consumer is a geometry shader, this is the
1327 * number of input vertices it accepts. Otherwise zero.
1329 * When num_tfeedback_decls is nonzero, it is permissible for the consumer to
1330 * be NULL. In this case, varying locations are assigned solely based on the
1331 * requirements of transform feedback.
1334 assign_varying_locations(struct gl_context
*ctx
,
1336 struct gl_shader_program
*prog
,
1337 gl_shader
*producer
, gl_shader
*consumer
,
1338 unsigned num_tfeedback_decls
,
1339 tfeedback_decl
*tfeedback_decls
,
1340 unsigned gs_input_vertices
)
1342 varying_matches
matches(ctx
->Const
.DisableVaryingPacking
,
1343 consumer
&& consumer
->Stage
== MESA_SHADER_FRAGMENT
);
1344 hash_table
*tfeedback_candidates
1345 = hash_table_ctor(0, hash_table_string_hash
, hash_table_string_compare
);
1346 hash_table
*consumer_inputs
1347 = hash_table_ctor(0, hash_table_string_hash
, hash_table_string_compare
);
1348 hash_table
*consumer_interface_inputs
1349 = hash_table_ctor(0, hash_table_string_hash
, hash_table_string_compare
);
1350 ir_variable
*consumer_inputs_with_locations
[VARYING_SLOT_MAX
] = {
1354 /* Operate in a total of four passes.
1356 * 1. Sort inputs / outputs into a canonical order. This is necessary so
1357 * that inputs / outputs of separable shaders will be assigned
1358 * predictable locations regardless of the order in which declarations
1359 * appeared in the shader source.
1361 * 2. Assign locations for any matching inputs and outputs.
1363 * 3. Mark output variables in the producer that do not have locations as
1364 * not being outputs. This lets the optimizer eliminate them.
1366 * 4. Mark input variables in the consumer that do not have locations as
1367 * not being inputs. This lets the optimizer eliminate them.
1370 canonicalize_shader_io(consumer
->ir
, ir_var_shader_in
);
1373 canonicalize_shader_io(producer
->ir
, ir_var_shader_out
);
1376 && !linker::populate_consumer_input_sets(mem_ctx
,
1379 consumer_interface_inputs
,
1380 consumer_inputs_with_locations
)) {
1381 assert(!"populate_consumer_input_sets failed");
1382 hash_table_dtor(tfeedback_candidates
);
1383 hash_table_dtor(consumer_inputs
);
1384 hash_table_dtor(consumer_interface_inputs
);
1389 foreach_in_list(ir_instruction
, node
, producer
->ir
) {
1390 ir_variable
*const output_var
= node
->as_variable();
1392 if ((output_var
== NULL
) ||
1393 (output_var
->data
.mode
!= ir_var_shader_out
))
1396 /* Only geometry shaders can use non-zero streams */
1397 assert(output_var
->data
.stream
== 0 ||
1398 (output_var
->data
.stream
< MAX_VERTEX_STREAMS
&&
1399 producer
->Stage
== MESA_SHADER_GEOMETRY
));
1401 tfeedback_candidate_generator
g(mem_ctx
, tfeedback_candidates
);
1402 g
.process(output_var
);
1404 ir_variable
*const input_var
=
1405 linker::get_matching_input(mem_ctx
, output_var
, consumer_inputs
,
1406 consumer_interface_inputs
,
1407 consumer_inputs_with_locations
);
1409 /* If a matching input variable was found, add this ouptut (and the
1410 * input) to the set. If this is a separable program and there is no
1411 * consumer stage, add the output.
1413 if (input_var
|| (prog
->SeparateShader
&& consumer
== NULL
)) {
1414 matches
.record(output_var
, input_var
);
1417 /* Only stream 0 outputs can be consumed in the next stage */
1418 if (input_var
&& output_var
->data
.stream
!= 0) {
1419 linker_error(prog
, "output %s is assigned to stream=%d but "
1420 "is linked to an input, which requires stream=0",
1421 output_var
->name
, output_var
->data
.stream
);
1426 /* If there's no producer stage, then this must be a separable program.
1427 * For example, we may have a program that has just a fragment shader.
1428 * Later this program will be used with some arbitrary vertex (or
1429 * geometry) shader program. This means that locations must be assigned
1430 * for all the inputs.
1432 foreach_in_list(ir_instruction
, node
, consumer
->ir
) {
1433 ir_variable
*const input_var
= node
->as_variable();
1435 if ((input_var
== NULL
) ||
1436 (input_var
->data
.mode
!= ir_var_shader_in
))
1439 matches
.record(NULL
, input_var
);
1443 for (unsigned i
= 0; i
< num_tfeedback_decls
; ++i
) {
1444 if (!tfeedback_decls
[i
].is_varying())
1447 const tfeedback_candidate
*matched_candidate
1448 = tfeedback_decls
[i
].find_candidate(prog
, tfeedback_candidates
);
1450 if (matched_candidate
== NULL
) {
1451 hash_table_dtor(tfeedback_candidates
);
1452 hash_table_dtor(consumer_inputs
);
1453 hash_table_dtor(consumer_interface_inputs
);
1457 if (matched_candidate
->toplevel_var
->data
.is_unmatched_generic_inout
)
1458 matches
.record(matched_candidate
->toplevel_var
, NULL
);
1461 const unsigned slots_used
= matches
.assign_locations();
1462 matches
.store_locations();
1464 for (unsigned i
= 0; i
< num_tfeedback_decls
; ++i
) {
1465 if (!tfeedback_decls
[i
].is_varying())
1468 if (!tfeedback_decls
[i
].assign_location(ctx
, prog
)) {
1469 hash_table_dtor(tfeedback_candidates
);
1470 hash_table_dtor(consumer_inputs
);
1471 hash_table_dtor(consumer_interface_inputs
);
1476 hash_table_dtor(tfeedback_candidates
);
1477 hash_table_dtor(consumer_inputs
);
1478 hash_table_dtor(consumer_interface_inputs
);
1480 if (ctx
->Const
.DisableVaryingPacking
) {
1481 /* Transform feedback code assumes varyings are packed, so if the driver
1482 * has disabled varying packing, make sure it does not support transform
1485 assert(!ctx
->Extensions
.EXT_transform_feedback
);
1488 lower_packed_varyings(mem_ctx
, slots_used
, ir_var_shader_out
,
1492 lower_packed_varyings(mem_ctx
, slots_used
, ir_var_shader_in
,
1493 gs_input_vertices
, consumer
);
1497 if (consumer
&& producer
) {
1498 foreach_in_list(ir_instruction
, node
, consumer
->ir
) {
1499 ir_variable
*const var
= node
->as_variable();
1501 if (var
&& var
->data
.mode
== ir_var_shader_in
&&
1502 var
->data
.is_unmatched_generic_inout
) {
1505 * On Page 91 (Page 97 of the PDF) of the GLSL ES 1.0 spec:
1507 * If the vertex shader declares but doesn't write to a
1508 * varying and the fragment shader declares and reads it,
1513 linker_warning(prog
, "%s shader varying %s not written "
1515 _mesa_shader_stage_to_string(consumer
->Stage
),
1517 _mesa_shader_stage_to_string(producer
->Stage
));
1518 } else if (prog
->Version
<= 120) {
1519 /* On page 25 (page 31 of the PDF) of the GLSL 1.20 spec:
1521 * Only those varying variables used (i.e. read) in
1522 * the fragment shader executable must be written to
1523 * by the vertex shader executable; declaring
1524 * superfluous varying variables in a vertex shader is
1527 * We interpret this text as meaning that the VS must
1528 * write the variable for the FS to read it. See
1529 * "glsl1-varying read but not written" in piglit.
1531 linker_error(prog
, "%s shader varying %s not written "
1533 _mesa_shader_stage_to_string(consumer
->Stage
),
1535 _mesa_shader_stage_to_string(producer
->Stage
));
1538 /* An 'in' variable is only really a shader input if its
1539 * value is written by the previous stage.
1541 var
->data
.mode
= ir_var_auto
;
1550 check_against_output_limit(struct gl_context
*ctx
,
1551 struct gl_shader_program
*prog
,
1552 gl_shader
*producer
)
1554 unsigned output_vectors
= 0;
1556 foreach_in_list(ir_instruction
, node
, producer
->ir
) {
1557 ir_variable
*const var
= node
->as_variable();
1559 if (var
&& var
->data
.mode
== ir_var_shader_out
&&
1560 var_counts_against_varying_limit(producer
->Stage
, var
)) {
1561 output_vectors
+= var
->type
->count_attribute_slots();
1565 assert(producer
->Stage
!= MESA_SHADER_FRAGMENT
);
1566 unsigned max_output_components
=
1567 ctx
->Const
.Program
[producer
->Stage
].MaxOutputComponents
;
1569 const unsigned output_components
= output_vectors
* 4;
1570 if (output_components
> max_output_components
) {
1571 if (ctx
->API
== API_OPENGLES2
|| prog
->IsES
)
1572 linker_error(prog
, "%s shader uses too many output vectors "
1574 _mesa_shader_stage_to_string(producer
->Stage
),
1576 max_output_components
/ 4);
1578 linker_error(prog
, "%s shader uses too many output components "
1580 _mesa_shader_stage_to_string(producer
->Stage
),
1582 max_output_components
);
1591 check_against_input_limit(struct gl_context
*ctx
,
1592 struct gl_shader_program
*prog
,
1593 gl_shader
*consumer
)
1595 unsigned input_vectors
= 0;
1597 foreach_in_list(ir_instruction
, node
, consumer
->ir
) {
1598 ir_variable
*const var
= node
->as_variable();
1600 if (var
&& var
->data
.mode
== ir_var_shader_in
&&
1601 var_counts_against_varying_limit(consumer
->Stage
, var
)) {
1602 input_vectors
+= var
->type
->count_attribute_slots();
1606 assert(consumer
->Stage
!= MESA_SHADER_VERTEX
);
1607 unsigned max_input_components
=
1608 ctx
->Const
.Program
[consumer
->Stage
].MaxInputComponents
;
1610 const unsigned input_components
= input_vectors
* 4;
1611 if (input_components
> max_input_components
) {
1612 if (ctx
->API
== API_OPENGLES2
|| prog
->IsES
)
1613 linker_error(prog
, "%s shader uses too many input vectors "
1615 _mesa_shader_stage_to_string(consumer
->Stage
),
1617 max_input_components
/ 4);
1619 linker_error(prog
, "%s shader uses too many input components "
1621 _mesa_shader_stage_to_string(consumer
->Stage
),
1623 max_input_components
);