Added few more stubs so that control reaches to DestroyDevice().
[mesa.git] / src / compiler / glsl / lower_distance.cpp
1 /*
2 * Copyright © 2011 Intel Corporation
3 *
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:
10 *
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
13 * Software.
14 *
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.
22 */
23
24 /**
25 * \file lower_distance.cpp
26 *
27 * This pass accounts for the difference between the way
28 * gl_ClipDistance is declared in standard GLSL (as an array of
29 * floats), and the way it is frequently implemented in hardware (as
30 * a pair of vec4s, with four clip distances packed into each).
31 *
32 * The declaration of gl_ClipDistance is replaced with a declaration
33 * of gl_ClipDistanceMESA, and any references to gl_ClipDistance are
34 * translated to refer to gl_ClipDistanceMESA with the appropriate
35 * swizzling of array indices. For instance:
36 *
37 * gl_ClipDistance[i]
38 *
39 * is translated into:
40 *
41 * gl_ClipDistanceMESA[i>>2][i&3]
42 *
43 * Since some hardware may not internally represent gl_ClipDistance as a pair
44 * of vec4's, this lowering pass is optional. To enable it, set the
45 * LowerCombinedClipCullDistance flag in gl_shader_compiler_options to true.
46 */
47
48 #include "main/macros.h"
49 #include "glsl_symbol_table.h"
50 #include "ir_rvalue_visitor.h"
51 #include "ir.h"
52 #include "program/prog_instruction.h" /* For WRITEMASK_* */
53 #include "main/mtypes.h"
54
55 #define GLSL_CLIP_VAR_NAME "gl_ClipDistanceMESA"
56
57 namespace {
58
59 class lower_distance_visitor : public ir_rvalue_visitor {
60 public:
61 explicit lower_distance_visitor(gl_shader_stage shader_stage,
62 const char *in_name, int total_size,
63 int offset)
64 : progress(false), old_distance_out_var(NULL),
65 old_distance_in_var(NULL), new_distance_out_var(NULL),
66 new_distance_in_var(NULL), shader_stage(shader_stage),
67 in_name(in_name), total_size(total_size), offset(offset)
68 {
69 }
70
71 explicit lower_distance_visitor(gl_shader_stage shader_stage,
72 const char *in_name,
73 const lower_distance_visitor *orig,
74 int offset)
75 : progress(false),
76 old_distance_out_var(NULL),
77 old_distance_in_var(NULL),
78 new_distance_out_var(orig->new_distance_out_var),
79 new_distance_in_var(orig->new_distance_in_var),
80 shader_stage(shader_stage),
81 in_name(in_name),
82 total_size(orig->total_size),
83 offset(offset)
84 {
85 }
86
87 virtual ir_visitor_status visit(ir_variable *);
88 void create_indices(ir_rvalue*, ir_rvalue *&, ir_rvalue *&);
89 bool is_distance_vec8(ir_rvalue *ir);
90 ir_rvalue *lower_distance_vec8(ir_rvalue *ir);
91 virtual ir_visitor_status visit_leave(ir_assignment *);
92 void visit_new_assignment(ir_assignment *ir);
93 virtual ir_visitor_status visit_leave(ir_call *);
94
95 virtual void handle_rvalue(ir_rvalue **rvalue);
96
97 void fix_lhs(ir_assignment *);
98
99 bool progress;
100
101 /**
102 * Pointer to the declaration of gl_ClipDistance, if found.
103 *
104 * Note:
105 *
106 * - the in_var is for geometry and both tessellation shader inputs only.
107 *
108 * - since gl_ClipDistance is available in tessellation control,
109 * tessellation evaluation and geometry shaders as both an input
110 * and an output, it's possible for both old_distance_out_var
111 * and old_distance_in_var to be non-null.
112 */
113 ir_variable *old_distance_out_var;
114 ir_variable *old_distance_in_var;
115
116 /**
117 * Pointer to the newly-created gl_ClipDistanceMESA variable.
118 */
119 ir_variable *new_distance_out_var;
120 ir_variable *new_distance_in_var;
121
122 /**
123 * Type of shader we are compiling (e.g. MESA_SHADER_VERTEX)
124 */
125 const gl_shader_stage shader_stage;
126 const char *in_name;
127 int total_size;
128 int offset;
129 };
130
131 } /* anonymous namespace */
132
133 /**
134 * Replace any declaration of 'in_name' as an array of floats with a
135 * declaration of gl_ClipDistanceMESA as an array of vec4's.
136 */
137 ir_visitor_status
138 lower_distance_visitor::visit(ir_variable *ir)
139 {
140 ir_variable **old_var;
141 ir_variable **new_var;
142
143 if (!ir->name || strcmp(ir->name, in_name) != 0)
144 return visit_continue;
145 assert (ir->type->is_array());
146
147 if (ir->data.mode == ir_var_shader_out) {
148 if (this->old_distance_out_var)
149 return visit_continue;
150 old_var = &old_distance_out_var;
151 new_var = &new_distance_out_var;
152 } else if (ir->data.mode == ir_var_shader_in) {
153 if (this->old_distance_in_var)
154 return visit_continue;
155 old_var = &old_distance_in_var;
156 new_var = &new_distance_in_var;
157 } else {
158 unreachable("not reached");
159 }
160
161 this->progress = true;
162
163 *old_var = ir;
164
165 if (!(*new_var)) {
166 unsigned new_size = (total_size + 3) / 4;
167
168 /* Clone the old var so that we inherit all of its properties */
169 *new_var = ir->clone(ralloc_parent(ir), NULL);
170 (*new_var)->name = ralloc_strdup(*new_var, GLSL_CLIP_VAR_NAME);
171 (*new_var)->data.location = VARYING_SLOT_CLIP_DIST0;
172
173 if (!ir->type->fields.array->is_array()) {
174 /* gl_ClipDistance (used for vertex, tessellation evaluation and
175 * geometry output, and fragment input).
176 */
177 assert((ir->data.mode == ir_var_shader_in &&
178 this->shader_stage == MESA_SHADER_FRAGMENT) ||
179 (ir->data.mode == ir_var_shader_out &&
180 (this->shader_stage == MESA_SHADER_VERTEX ||
181 this->shader_stage == MESA_SHADER_TESS_EVAL ||
182 this->shader_stage == MESA_SHADER_GEOMETRY)));
183
184 assert (ir->type->fields.array == glsl_type::float_type);
185 (*new_var)->data.max_array_access = new_size - 1;
186
187 /* And change the properties that we need to change */
188 (*new_var)->type = glsl_type::get_array_instance(glsl_type::vec4_type,
189 new_size);
190 } else {
191 /* 2D gl_ClipDistance (used for tessellation control, tessellation
192 * evaluation and geometry input, and tessellation control output).
193 */
194 assert((ir->data.mode == ir_var_shader_in &&
195 (this->shader_stage == MESA_SHADER_GEOMETRY ||
196 this->shader_stage == MESA_SHADER_TESS_EVAL)) ||
197 this->shader_stage == MESA_SHADER_TESS_CTRL);
198
199 assert (ir->type->fields.array->fields.array == glsl_type::float_type);
200
201 /* And change the properties that we need to change */
202 (*new_var)->type = glsl_type::get_array_instance(
203 glsl_type::get_array_instance(glsl_type::vec4_type,
204 new_size),
205 ir->type->array_size());
206 }
207 ir->replace_with(*new_var);
208 } else {
209 ir->remove();
210 }
211
212 return visit_continue;
213 }
214
215
216 /**
217 * Create the necessary GLSL rvalues to index into gl_ClipDistanceMESA based
218 * on the rvalue previously used to index into gl_ClipDistance.
219 *
220 * \param array_index Selects one of the vec4's in gl_ClipDistanceMESA
221 * \param swizzle_index Selects a component within the vec4 selected by
222 * array_index.
223 */
224 void
225 lower_distance_visitor::create_indices(ir_rvalue *old_index,
226 ir_rvalue *&array_index,
227 ir_rvalue *&swizzle_index)
228 {
229 void *ctx = ralloc_parent(old_index);
230
231 /* Make sure old_index is a signed int so that the bitwise "shift" and
232 * "and" operations below type check properly.
233 */
234 if (old_index->type != glsl_type::int_type) {
235 assert (old_index->type == glsl_type::uint_type);
236 old_index = new(ctx) ir_expression(ir_unop_u2i, old_index);
237 }
238
239 ir_constant *old_index_constant =
240 old_index->constant_expression_value(ctx);
241 if (old_index_constant) {
242 /* gl_ClipDistance is being accessed via a constant index. Don't bother
243 * creating expressions to calculate the lowered indices. Just create
244 * constants.
245 */
246 int const_val = old_index_constant->get_int_component(0) + offset;
247 array_index = new(ctx) ir_constant(const_val / 4);
248 swizzle_index = new(ctx) ir_constant(const_val % 4);
249 } else {
250 /* Create a variable to hold the value of old_index (so that we
251 * don't compute it twice).
252 */
253 ir_variable *old_index_var = new(ctx) ir_variable(
254 glsl_type::int_type, "distance_index", ir_var_temporary);
255 this->base_ir->insert_before(old_index_var);
256 this->base_ir->insert_before(new(ctx) ir_assignment(
257 new(ctx) ir_dereference_variable(old_index_var), old_index));
258
259 /* Create the expression distance_index / 4. Do this as a bit
260 * shift because that's likely to be more efficient.
261 */
262 array_index = new(ctx) ir_expression(
263 ir_binop_rshift,
264 new(ctx) ir_expression(ir_binop_add,
265 new(ctx) ir_dereference_variable(old_index_var),
266 new(ctx) ir_constant(offset)),
267 new(ctx) ir_constant(2));
268
269 /* Create the expression distance_index % 4. Do this as a bitwise
270 * AND because that's likely to be more efficient.
271 */
272 swizzle_index = new(ctx) ir_expression(
273 ir_binop_bit_and,
274 new(ctx) ir_expression(ir_binop_add,
275 new(ctx) ir_dereference_variable(old_index_var),
276 new(ctx) ir_constant(offset)),
277 new(ctx) ir_constant(3));
278 }
279 }
280
281
282 /**
283 * Determine whether the given rvalue describes an array of 8 floats that
284 * needs to be lowered to an array of 2 vec4's; that is, determine whether it
285 * matches one of the following patterns:
286 *
287 * - gl_ClipDistance (if gl_ClipDistance is 1D)
288 * - gl_ClipDistance[i] (if gl_ClipDistance is 2D)
289 */
290 bool
291 lower_distance_visitor::is_distance_vec8(ir_rvalue *ir)
292 {
293 /* Note that geometry shaders contain gl_ClipDistance both as an input
294 * (which is a 2D array) and an output (which is a 1D array), so it's
295 * possible for both this->old_distance_out_var and
296 * this->old_distance_in_var to be non-NULL in the same shader.
297 */
298
299 if (!ir->type->is_array())
300 return false;
301 if (ir->type->fields.array != glsl_type::float_type)
302 return false;
303
304 if (this->old_distance_out_var) {
305 if (ir->variable_referenced() == this->old_distance_out_var)
306 return true;
307 }
308 if (this->old_distance_in_var) {
309 assert(this->shader_stage == MESA_SHADER_TESS_CTRL ||
310 this->shader_stage == MESA_SHADER_TESS_EVAL ||
311 this->shader_stage == MESA_SHADER_GEOMETRY ||
312 this->shader_stage == MESA_SHADER_FRAGMENT);
313
314 if (ir->variable_referenced() == this->old_distance_in_var)
315 return true;
316 }
317 return false;
318 }
319
320
321 /**
322 * If the given ir satisfies is_distance_vec8(), return new ir
323 * representing its lowered equivalent. That is, map:
324 *
325 * - gl_ClipDistance => gl_ClipDistanceMESA (if gl_ClipDistance is 1D)
326 * - gl_ClipDistance[i] => gl_ClipDistanceMESA[i] (if gl_ClipDistance is 2D)
327 *
328 * Otherwise return NULL.
329 */
330 ir_rvalue *
331 lower_distance_visitor::lower_distance_vec8(ir_rvalue *ir)
332 {
333 if (!ir->type->is_array())
334 return NULL;
335 if (ir->type->fields.array != glsl_type::float_type)
336 return NULL;
337
338 ir_variable **new_var = NULL;
339 if (this->old_distance_out_var) {
340 if (ir->variable_referenced() == this->old_distance_out_var)
341 new_var = &this->new_distance_out_var;
342 }
343 if (this->old_distance_in_var) {
344 if (ir->variable_referenced() == this->old_distance_in_var)
345 new_var = &this->new_distance_in_var;
346 }
347 if (new_var == NULL)
348 return NULL;
349
350 if (ir->as_dereference_variable()) {
351 return new(ralloc_parent(ir)) ir_dereference_variable(*new_var);
352 } else {
353 ir_dereference_array *array_ref = ir->as_dereference_array();
354 assert(array_ref);
355 assert(array_ref->array->as_dereference_variable());
356
357 return new(ralloc_parent(ir))
358 ir_dereference_array(*new_var, array_ref->array_index);
359 }
360 }
361
362
363 void
364 lower_distance_visitor::handle_rvalue(ir_rvalue **rv)
365 {
366 if (*rv == NULL)
367 return;
368
369 ir_dereference_array *const array_deref = (*rv)->as_dereference_array();
370 if (array_deref == NULL)
371 return;
372
373 /* Replace any expression that indexes one of the floats in gl_ClipDistance
374 * with an expression that indexes into one of the vec4's in
375 * gl_ClipDistanceMESA and accesses the appropriate component.
376 */
377 ir_rvalue *lowered_vec8 =
378 this->lower_distance_vec8(array_deref->array);
379 if (lowered_vec8 != NULL) {
380 this->progress = true;
381 ir_rvalue *array_index;
382 ir_rvalue *swizzle_index;
383 this->create_indices(array_deref->array_index, array_index, swizzle_index);
384 void *mem_ctx = ralloc_parent(array_deref);
385
386 ir_dereference_array *const new_array_deref =
387 new(mem_ctx) ir_dereference_array(lowered_vec8, array_index);
388
389 ir_expression *const expr =
390 new(mem_ctx) ir_expression(ir_binop_vector_extract,
391 new_array_deref,
392 swizzle_index);
393
394 *rv = expr;
395 }
396 }
397
398 void
399 lower_distance_visitor::fix_lhs(ir_assignment *ir)
400 {
401 if (ir->lhs->ir_type == ir_type_expression) {
402 void *mem_ctx = ralloc_parent(ir);
403 ir_expression *const expr = (ir_expression *) ir->lhs;
404
405 /* The expression must be of the form:
406 *
407 * (vector_extract gl_ClipDistanceMESA[i], j).
408 */
409 assert(expr->operation == ir_binop_vector_extract);
410 assert(expr->operands[0]->ir_type == ir_type_dereference_array);
411 assert(expr->operands[0]->type == glsl_type::vec4_type);
412
413 ir_dereference *const new_lhs = (ir_dereference *) expr->operands[0];
414 ir->rhs = new(mem_ctx) ir_expression(ir_triop_vector_insert,
415 glsl_type::vec4_type,
416 new_lhs->clone(mem_ctx, NULL),
417 ir->rhs,
418 expr->operands[1]);
419 ir->set_lhs(new_lhs);
420 ir->write_mask = WRITEMASK_XYZW;
421 }
422 }
423
424 /**
425 * Replace any assignment having the 1D gl_ClipDistance (undereferenced) as
426 * its LHS or RHS with a sequence of assignments, one for each component of
427 * the array. Each of these assignments is lowered to refer to
428 * gl_ClipDistanceMESA as appropriate.
429 *
430 * We need to do a similar replacement for 2D gl_ClipDistance, however since
431 * it's an input, the only case we need to address is where a 1D slice of it
432 * is the entire RHS of an assignment, e.g.:
433 *
434 * foo = gl_in[i].gl_ClipDistance
435 */
436 ir_visitor_status
437 lower_distance_visitor::visit_leave(ir_assignment *ir)
438 {
439 /* First invoke the base class visitor. This causes handle_rvalue() to be
440 * called on ir->rhs and ir->condition.
441 */
442 ir_rvalue_visitor::visit_leave(ir);
443
444 if (this->is_distance_vec8(ir->lhs) ||
445 this->is_distance_vec8(ir->rhs)) {
446 /* LHS or RHS of the assignment is the entire 1D gl_ClipDistance array
447 * (or a 1D slice of a 2D gl_ClipDistance input array). Since we are
448 * reshaping gl_ClipDistance from an array of floats to an array of
449 * vec4's, this isn't going to work as a bulk assignment anymore, so
450 * unroll it to element-by-element assignments and lower each of them.
451 *
452 * Note: to unroll into element-by-element assignments, we need to make
453 * clones of the LHS and RHS. This is safe because expressions and
454 * l-values are side-effect free.
455 */
456 void *ctx = ralloc_parent(ir);
457 int array_size = ir->lhs->type->array_size();
458 for (int i = 0; i < array_size; ++i) {
459 ir_dereference_array *new_lhs = new(ctx) ir_dereference_array(
460 ir->lhs->clone(ctx, NULL), new(ctx) ir_constant(i));
461 ir_dereference_array *new_rhs = new(ctx) ir_dereference_array(
462 ir->rhs->clone(ctx, NULL), new(ctx) ir_constant(i));
463 this->handle_rvalue((ir_rvalue **) &new_rhs);
464
465 /* Handle the LHS after creating the new assignment. This must
466 * happen in this order because handle_rvalue may replace the old LHS
467 * with an ir_expression of ir_binop_vector_extract. Since this is
468 * not a valide l-value, this will cause an assertion in the
469 * ir_assignment constructor to fail.
470 *
471 * If this occurs, replace the mangled LHS with a dereference of the
472 * vector, and replace the RHS with an ir_triop_vector_insert.
473 */
474 ir_assignment *const assign = new(ctx) ir_assignment(new_lhs, new_rhs);
475 this->handle_rvalue((ir_rvalue **) &assign->lhs);
476 this->fix_lhs(assign);
477
478 this->base_ir->insert_before(assign);
479 }
480 ir->remove();
481
482 return visit_continue;
483 }
484
485 /* Handle the LHS as if it were an r-value. Normally
486 * rvalue_visit(ir_assignment *) only visits the RHS, but we need to lower
487 * expressions in the LHS as well.
488 *
489 * This may cause the LHS to get replaced with an ir_expression of
490 * ir_binop_vector_extract. If this occurs, replace it with a dereference
491 * of the vector, and replace the RHS with an ir_triop_vector_insert.
492 */
493 handle_rvalue((ir_rvalue **)&ir->lhs);
494 this->fix_lhs(ir);
495
496 return rvalue_visit(ir);
497 }
498
499
500 /**
501 * Set up base_ir properly and call visit_leave() on a newly created
502 * ir_assignment node. This is used in cases where we have to insert an
503 * ir_assignment in a place where we know the hierarchical visitor won't see
504 * it.
505 */
506 void
507 lower_distance_visitor::visit_new_assignment(ir_assignment *ir)
508 {
509 ir_instruction *old_base_ir = this->base_ir;
510 this->base_ir = ir;
511 ir->accept(this);
512 this->base_ir = old_base_ir;
513 }
514
515
516 /**
517 * If a 1D gl_ClipDistance variable appears as an argument in an ir_call
518 * expression, replace it with a temporary variable, and make sure the ir_call
519 * is preceded and/or followed by assignments that copy the contents of the
520 * temporary variable to and/or from gl_ClipDistance. Each of these
521 * assignments is then lowered to refer to gl_ClipDistanceMESA.
522 *
523 * We need to do a similar replacement for 2D gl_ClipDistance, however since
524 * it's an input, the only case we need to address is where a 1D slice of it
525 * is passed as an "in" parameter to an ir_call, e.g.:
526 *
527 * foo(gl_in[i].gl_ClipDistance)
528 */
529 ir_visitor_status
530 lower_distance_visitor::visit_leave(ir_call *ir)
531 {
532 void *ctx = ralloc_parent(ir);
533
534 const exec_node *formal_param_node = ir->callee->parameters.get_head_raw();
535 const exec_node *actual_param_node = ir->actual_parameters.get_head_raw();
536 while (!actual_param_node->is_tail_sentinel()) {
537 ir_variable *formal_param = (ir_variable *) formal_param_node;
538 ir_rvalue *actual_param = (ir_rvalue *) actual_param_node;
539
540 /* Advance formal_param_node and actual_param_node now so that we can
541 * safely replace actual_param with another node, if necessary, below.
542 */
543 formal_param_node = formal_param_node->next;
544 actual_param_node = actual_param_node->next;
545
546 if (this->is_distance_vec8(actual_param)) {
547 /* User is trying to pass the whole 1D gl_ClipDistance array (or a 1D
548 * slice of a 2D gl_ClipDistance array) to a function call. Since we
549 * are reshaping gl_ClipDistance from an array of floats to an array
550 * of vec4's, this isn't going to work anymore, so use a temporary
551 * array instead.
552 */
553 ir_variable *temp_clip_distance = new(ctx) ir_variable(
554 actual_param->type, "temp_clip_distance", ir_var_temporary);
555 this->base_ir->insert_before(temp_clip_distance);
556 actual_param->replace_with(
557 new(ctx) ir_dereference_variable(temp_clip_distance));
558 if (formal_param->data.mode == ir_var_function_in
559 || formal_param->data.mode == ir_var_function_inout) {
560 /* Copy from gl_ClipDistance to the temporary before the call.
561 * Since we are going to insert this copy before the current
562 * instruction, we need to visit it afterwards to make sure it
563 * gets lowered.
564 */
565 ir_assignment *new_assignment = new(ctx) ir_assignment(
566 new(ctx) ir_dereference_variable(temp_clip_distance),
567 actual_param->clone(ctx, NULL));
568 this->base_ir->insert_before(new_assignment);
569 this->visit_new_assignment(new_assignment);
570 }
571 if (formal_param->data.mode == ir_var_function_out
572 || formal_param->data.mode == ir_var_function_inout) {
573 /* Copy from the temporary to gl_ClipDistance after the call.
574 * Since visit_list_elements() has already decided which
575 * instruction it's going to visit next, we need to visit
576 * afterwards to make sure it gets lowered.
577 */
578 ir_assignment *new_assignment = new(ctx) ir_assignment(
579 actual_param->clone(ctx, NULL),
580 new(ctx) ir_dereference_variable(temp_clip_distance));
581 this->base_ir->insert_after(new_assignment);
582 this->visit_new_assignment(new_assignment);
583 }
584 }
585 }
586
587 return rvalue_visit(ir);
588 }
589
590 namespace {
591 class lower_distance_visitor_counter : public ir_rvalue_visitor {
592 public:
593 explicit lower_distance_visitor_counter(void)
594 : in_clip_size(0), in_cull_size(0),
595 out_clip_size(0), out_cull_size(0)
596 {
597 }
598
599 virtual ir_visitor_status visit(ir_variable *);
600 virtual void handle_rvalue(ir_rvalue **rvalue);
601
602 int in_clip_size;
603 int in_cull_size;
604 int out_clip_size;
605 int out_cull_size;
606 };
607
608 }
609 /**
610 * Count gl_ClipDistance and gl_CullDistance sizes.
611 */
612 ir_visitor_status
613 lower_distance_visitor_counter::visit(ir_variable *ir)
614 {
615 int *clip_size, *cull_size;
616
617 if (!ir->name)
618 return visit_continue;
619
620 if (ir->data.mode == ir_var_shader_out) {
621 clip_size = &out_clip_size;
622 cull_size = &out_cull_size;
623 } else if (ir->data.mode == ir_var_shader_in) {
624 clip_size = &in_clip_size;
625 cull_size = &in_cull_size;
626 } else
627 return visit_continue;
628
629 if (ir->type->is_unsized_array())
630 return visit_continue;
631
632 if (*clip_size == 0) {
633 if (!strcmp(ir->name, "gl_ClipDistance")) {
634 if (!ir->type->fields.array->is_array())
635 *clip_size = ir->type->array_size();
636 else
637 *clip_size = ir->type->fields.array->array_size();
638 }
639 }
640
641 if (*cull_size == 0) {
642 if (!strcmp(ir->name, "gl_CullDistance")) {
643 if (!ir->type->fields.array->is_array())
644 *cull_size = ir->type->array_size();
645 else
646 *cull_size = ir->type->fields.array->array_size();
647 }
648 }
649 return visit_continue;
650 }
651
652 void
653 lower_distance_visitor_counter::handle_rvalue(ir_rvalue **)
654 {
655 return;
656 }
657
658 bool
659 lower_clip_cull_distance(struct gl_shader_program *prog,
660 struct gl_linked_shader *shader)
661 {
662 int clip_size, cull_size;
663
664 lower_distance_visitor_counter count;
665 visit_list_elements(&count, shader->ir);
666
667 clip_size = MAX2(count.in_clip_size, count.out_clip_size);
668 cull_size = MAX2(count.in_cull_size, count.out_cull_size);
669
670 if (clip_size == 0 && cull_size == 0)
671 return false;
672
673 lower_distance_visitor v(shader->Stage, "gl_ClipDistance", clip_size + cull_size, 0);
674 visit_list_elements(&v, shader->ir);
675
676 lower_distance_visitor v2(shader->Stage, "gl_CullDistance", &v, clip_size);
677 visit_list_elements(&v2, shader->ir);
678
679 if (v2.new_distance_out_var)
680 shader->symbols->add_variable(v2.new_distance_out_var);
681 if (v2.new_distance_in_var)
682 shader->symbols->add_variable(v2.new_distance_in_var);
683
684 return v2.progress;
685 }