2 * Copyright © 2015 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 DEALINGS
24 #include "vtn_private.h"
25 #include "nir/nir_vla.h"
28 vtn_cfg_handle_prepass_instruction(struct vtn_builder
*b
, SpvOp opcode
,
29 const uint32_t *w
, unsigned count
)
33 assert(b
->func
== NULL
);
34 b
->func
= rzalloc(b
, struct vtn_function
);
36 list_inithead(&b
->func
->body
);
37 b
->func
->control
= w
[3];
39 MAYBE_UNUSED
const struct glsl_type
*result_type
=
40 vtn_value(b
, w
[1], vtn_value_type_type
)->type
->type
;
41 struct vtn_value
*val
= vtn_push_value(b
, w
[2], vtn_value_type_function
);
44 const struct vtn_type
*func_type
=
45 vtn_value(b
, w
[4], vtn_value_type_type
)->type
;
47 assert(func_type
->return_type
->type
== result_type
);
50 nir_function_create(b
->shader
, ralloc_strdup(b
->shader
, val
->name
));
52 func
->num_params
= func_type
->length
;
53 func
->params
= ralloc_array(b
->shader
, nir_parameter
, func
->num_params
);
54 for (unsigned i
= 0; i
< func
->num_params
; i
++) {
55 if (func_type
->params
[i
]->base_type
== vtn_base_type_pointer
) {
56 func
->params
[i
].type
= func_type
->params
[i
]->deref
->type
;
58 func
->params
[i
].type
= func_type
->params
[i
]->type
;
61 /* TODO: We could do something smarter here. */
62 func
->params
[i
].param_type
= nir_parameter_inout
;
65 func
->return_type
= func_type
->return_type
->type
;
67 b
->func
->impl
= nir_function_impl_create(func
);
68 b
->nb
.cursor
= nir_before_cf_list(&b
->func
->impl
->body
);
70 b
->func_param_idx
= 0;
74 case SpvOpFunctionEnd
:
79 case SpvOpFunctionParameter
: {
80 struct vtn_type
*type
= vtn_value(b
, w
[1], vtn_value_type_type
)->type
;
82 assert(b
->func_param_idx
< b
->func
->impl
->num_params
);
83 nir_variable
*param
= b
->func
->impl
->params
[b
->func_param_idx
++];
85 if (type
->base_type
== vtn_base_type_pointer
) {
86 struct vtn_variable
*vtn_var
= rzalloc(b
, struct vtn_variable
);
87 vtn_var
->type
= type
->deref
;
90 assert(vtn_var
->type
->type
== param
->type
);
92 struct vtn_type
*without_array
= vtn_var
->type
;
93 while(glsl_type_is_array(without_array
->type
))
94 without_array
= without_array
->array_element
;
96 if (glsl_type_is_image(without_array
->type
)) {
97 vtn_var
->mode
= vtn_variable_mode_image
;
98 param
->interface_type
= without_array
->type
;
99 } else if (glsl_type_is_sampler(without_array
->type
)) {
100 vtn_var
->mode
= vtn_variable_mode_sampler
;
101 param
->interface_type
= without_array
->type
;
103 vtn_var
->mode
= vtn_variable_mode_param
;
106 struct vtn_value
*val
=
107 vtn_push_value(b
, w
[2], vtn_value_type_pointer
);
109 /* Name the parameter so it shows up nicely in NIR */
110 param
->name
= ralloc_strdup(param
, val
->name
);
112 val
->pointer
= vtn_pointer_for_variable(b
, vtn_var
, type
);
114 /* We're a regular SSA value. */
115 struct vtn_value
*val
= vtn_push_value(b
, w
[2], vtn_value_type_ssa
);
117 /* Name the parameter so it shows up nicely in NIR */
118 param
->name
= ralloc_strdup(param
, val
->name
);
120 val
->ssa
= vtn_local_load(b
, nir_deref_var_create(b
, param
));
126 assert(b
->block
== NULL
);
127 b
->block
= rzalloc(b
, struct vtn_block
);
128 b
->block
->node
.type
= vtn_cf_node_type_block
;
130 vtn_push_value(b
, w
[1], vtn_value_type_block
)->block
= b
->block
;
132 if (b
->func
->start_block
== NULL
) {
133 /* This is the first block encountered for this function. In this
134 * case, we set the start block and add it to the list of
135 * implemented functions that we'll walk later.
137 b
->func
->start_block
= b
->block
;
138 exec_list_push_tail(&b
->functions
, &b
->func
->node
);
143 case SpvOpSelectionMerge
:
145 assert(b
->block
&& b
->block
->merge
== NULL
);
150 case SpvOpBranchConditional
:
154 case SpvOpReturnValue
:
155 case SpvOpUnreachable
:
156 assert(b
->block
&& b
->block
->branch
== NULL
);
157 b
->block
->branch
= w
;
162 /* Continue on as per normal */
170 vtn_add_case(struct vtn_builder
*b
, struct vtn_switch
*swtch
,
171 struct vtn_block
*break_block
,
172 uint32_t block_id
, uint32_t val
, bool is_default
)
174 struct vtn_block
*case_block
=
175 vtn_value(b
, block_id
, vtn_value_type_block
)->block
;
177 /* Don't create dummy cases that just break */
178 if (case_block
== break_block
)
181 if (case_block
->switch_case
== NULL
) {
182 struct vtn_case
*c
= ralloc(b
, struct vtn_case
);
184 list_inithead(&c
->body
);
185 c
->start_block
= case_block
;
186 c
->fallthrough
= NULL
;
187 util_dynarray_init(&c
->values
, b
);
188 c
->is_default
= false;
191 list_addtail(&c
->link
, &swtch
->cases
);
193 case_block
->switch_case
= c
;
197 case_block
->switch_case
->is_default
= true;
199 util_dynarray_append(&case_block
->switch_case
->values
, uint32_t, val
);
203 /* This function performs a depth-first search of the cases and puts them
204 * in fall-through order.
207 vtn_order_case(struct vtn_switch
*swtch
, struct vtn_case
*cse
)
214 list_del(&cse
->link
);
216 if (cse
->fallthrough
) {
217 vtn_order_case(swtch
, cse
->fallthrough
);
219 /* If we have a fall-through, place this case right before the case it
220 * falls through to. This ensures that fallthroughs come one after
221 * the other. These two can never get separated because that would
222 * imply something else falling through to the same case. Also, this
223 * can't break ordering because the DFS ensures that this case is
224 * visited before anything that falls through to it.
226 list_addtail(&cse
->link
, &cse
->fallthrough
->link
);
228 list_add(&cse
->link
, &swtch
->cases
);
232 static enum vtn_branch_type
233 vtn_get_branch_type(struct vtn_block
*block
,
234 struct vtn_case
*swcase
, struct vtn_block
*switch_break
,
235 struct vtn_block
*loop_break
, struct vtn_block
*loop_cont
)
237 if (block
->switch_case
) {
238 /* This branch is actually a fallthrough */
239 assert(swcase
->fallthrough
== NULL
||
240 swcase
->fallthrough
== block
->switch_case
);
241 swcase
->fallthrough
= block
->switch_case
;
242 return vtn_branch_type_switch_fallthrough
;
243 } else if (block
== loop_break
) {
244 return vtn_branch_type_loop_break
;
245 } else if (block
== loop_cont
) {
246 return vtn_branch_type_loop_continue
;
247 } else if (block
== switch_break
) {
248 return vtn_branch_type_switch_break
;
250 return vtn_branch_type_none
;
255 vtn_cfg_walk_blocks(struct vtn_builder
*b
, struct list_head
*cf_list
,
256 struct vtn_block
*start
, struct vtn_case
*switch_case
,
257 struct vtn_block
*switch_break
,
258 struct vtn_block
*loop_break
, struct vtn_block
*loop_cont
,
259 struct vtn_block
*end
)
261 struct vtn_block
*block
= start
;
262 while (block
!= end
) {
263 if (block
->merge
&& (*block
->merge
& SpvOpCodeMask
) == SpvOpLoopMerge
&&
265 struct vtn_loop
*loop
= ralloc(b
, struct vtn_loop
);
267 loop
->node
.type
= vtn_cf_node_type_loop
;
268 list_inithead(&loop
->body
);
269 list_inithead(&loop
->cont_body
);
270 loop
->control
= block
->merge
[3];
272 list_addtail(&loop
->node
.link
, cf_list
);
275 struct vtn_block
*new_loop_break
=
276 vtn_value(b
, block
->merge
[1], vtn_value_type_block
)->block
;
277 struct vtn_block
*new_loop_cont
=
278 vtn_value(b
, block
->merge
[2], vtn_value_type_block
)->block
;
280 /* Note: This recursive call will start with the current block as
281 * its start block. If we weren't careful, we would get here
282 * again and end up in infinite recursion. This is why we set
283 * block->loop above and check for it before creating one. This
284 * way, we only create the loop once and the second call that
285 * tries to handle this loop goes to the cases below and gets
286 * handled as a regular block.
288 * Note: When we make the recursive walk calls, we pass NULL for
289 * the switch break since you have to break out of the loop first.
290 * We do, however, still pass the current switch case because it's
291 * possible that the merge block for the loop is the start of
294 vtn_cfg_walk_blocks(b
, &loop
->body
, block
, switch_case
, NULL
,
295 new_loop_break
, new_loop_cont
, NULL
);
296 vtn_cfg_walk_blocks(b
, &loop
->cont_body
, new_loop_cont
, NULL
, NULL
,
297 new_loop_break
, NULL
, block
);
299 block
= new_loop_break
;
303 assert(block
->node
.link
.next
== NULL
);
304 list_addtail(&block
->node
.link
, cf_list
);
306 switch (*block
->branch
& SpvOpCodeMask
) {
308 struct vtn_block
*branch_block
=
309 vtn_value(b
, block
->branch
[1], vtn_value_type_block
)->block
;
311 block
->branch_type
= vtn_get_branch_type(branch_block
,
312 switch_case
, switch_break
,
313 loop_break
, loop_cont
);
315 if (block
->branch_type
!= vtn_branch_type_none
)
318 block
= branch_block
;
323 case SpvOpReturnValue
:
324 block
->branch_type
= vtn_branch_type_return
;
328 block
->branch_type
= vtn_branch_type_discard
;
331 case SpvOpBranchConditional
: {
332 struct vtn_block
*then_block
=
333 vtn_value(b
, block
->branch
[2], vtn_value_type_block
)->block
;
334 struct vtn_block
*else_block
=
335 vtn_value(b
, block
->branch
[3], vtn_value_type_block
)->block
;
337 struct vtn_if
*if_stmt
= ralloc(b
, struct vtn_if
);
339 if_stmt
->node
.type
= vtn_cf_node_type_if
;
340 if_stmt
->condition
= block
->branch
[1];
341 list_inithead(&if_stmt
->then_body
);
342 list_inithead(&if_stmt
->else_body
);
344 list_addtail(&if_stmt
->node
.link
, cf_list
);
347 (*block
->merge
& SpvOpCodeMask
) == SpvOpSelectionMerge
) {
348 if_stmt
->control
= block
->merge
[2];
351 if_stmt
->then_type
= vtn_get_branch_type(then_block
,
352 switch_case
, switch_break
,
353 loop_break
, loop_cont
);
354 if_stmt
->else_type
= vtn_get_branch_type(else_block
,
355 switch_case
, switch_break
,
356 loop_break
, loop_cont
);
358 if (if_stmt
->then_type
== vtn_branch_type_none
&&
359 if_stmt
->else_type
== vtn_branch_type_none
) {
360 /* Neither side of the if is something we can short-circuit. */
361 assert((*block
->merge
& SpvOpCodeMask
) == SpvOpSelectionMerge
);
362 struct vtn_block
*merge_block
=
363 vtn_value(b
, block
->merge
[1], vtn_value_type_block
)->block
;
365 vtn_cfg_walk_blocks(b
, &if_stmt
->then_body
, then_block
,
366 switch_case
, switch_break
,
367 loop_break
, loop_cont
, merge_block
);
368 vtn_cfg_walk_blocks(b
, &if_stmt
->else_body
, else_block
,
369 switch_case
, switch_break
,
370 loop_break
, loop_cont
, merge_block
);
372 enum vtn_branch_type merge_type
=
373 vtn_get_branch_type(merge_block
, switch_case
, switch_break
,
374 loop_break
, loop_cont
);
375 if (merge_type
== vtn_branch_type_none
) {
381 } else if (if_stmt
->then_type
!= vtn_branch_type_none
&&
382 if_stmt
->else_type
!= vtn_branch_type_none
) {
383 /* Both sides were short-circuited. We're done here. */
386 /* Exeactly one side of the branch could be short-circuited.
387 * We set the branch up as a predicated break/continue and we
388 * continue on with the other side as if it were what comes
391 if (if_stmt
->then_type
== vtn_branch_type_none
) {
398 unreachable("Should have returned or continued");
402 assert((*block
->merge
& SpvOpCodeMask
) == SpvOpSelectionMerge
);
403 struct vtn_block
*break_block
=
404 vtn_value(b
, block
->merge
[1], vtn_value_type_block
)->block
;
406 struct vtn_switch
*swtch
= ralloc(b
, struct vtn_switch
);
408 swtch
->node
.type
= vtn_cf_node_type_switch
;
409 swtch
->selector
= block
->branch
[1];
410 list_inithead(&swtch
->cases
);
412 list_addtail(&swtch
->node
.link
, cf_list
);
414 /* First, we go through and record all of the cases. */
415 const uint32_t *branch_end
=
416 block
->branch
+ (block
->branch
[0] >> SpvWordCountShift
);
418 vtn_add_case(b
, swtch
, break_block
, block
->branch
[2], 0, true);
419 for (const uint32_t *w
= block
->branch
+ 3; w
< branch_end
; w
+= 2)
420 vtn_add_case(b
, swtch
, break_block
, w
[1], w
[0], false);
422 /* Now, we go through and walk the blocks. While we walk through
423 * the blocks, we also gather the much-needed fall-through
426 list_for_each_entry(struct vtn_case
, cse
, &swtch
->cases
, link
) {
427 assert(cse
->start_block
!= break_block
);
428 vtn_cfg_walk_blocks(b
, &cse
->body
, cse
->start_block
, cse
,
429 break_block
, NULL
, loop_cont
, NULL
);
432 /* Finally, we walk over all of the cases one more time and put
433 * them in fall-through order.
435 for (const uint32_t *w
= block
->branch
+ 2; w
< branch_end
; w
+= 2) {
436 struct vtn_block
*case_block
=
437 vtn_value(b
, *w
, vtn_value_type_block
)->block
;
439 if (case_block
== break_block
)
442 assert(case_block
->switch_case
);
444 vtn_order_case(swtch
, case_block
->switch_case
);
447 enum vtn_branch_type branch_type
=
448 vtn_get_branch_type(break_block
, switch_case
, NULL
,
449 loop_break
, loop_cont
);
451 if (branch_type
!= vtn_branch_type_none
) {
452 /* It is possible that the break is actually the continue block
453 * for the containing loop. In this case, we need to bail and let
454 * the loop parsing code handle the continue properly.
456 assert(branch_type
== vtn_branch_type_loop_continue
);
464 case SpvOpUnreachable
:
468 unreachable("Unhandled opcode");
474 vtn_build_cfg(struct vtn_builder
*b
, const uint32_t *words
, const uint32_t *end
)
476 vtn_foreach_instruction(b
, words
, end
,
477 vtn_cfg_handle_prepass_instruction
);
479 foreach_list_typed(struct vtn_function
, func
, node
, &b
->functions
) {
480 vtn_cfg_walk_blocks(b
, &func
->body
, func
->start_block
,
481 NULL
, NULL
, NULL
, NULL
, NULL
);
486 vtn_handle_phis_first_pass(struct vtn_builder
*b
, SpvOp opcode
,
487 const uint32_t *w
, unsigned count
)
489 if (opcode
== SpvOpLabel
)
490 return true; /* Nothing to do */
492 /* If this isn't a phi node, stop. */
493 if (opcode
!= SpvOpPhi
)
496 /* For handling phi nodes, we do a poor-man's out-of-ssa on the spot.
497 * For each phi, we create a variable with the appropreate type and
498 * do a load from that variable. Then, in a second pass, we add
499 * stores to that variable to each of the predecessor blocks.
501 * We could do something more intelligent here. However, in order to
502 * handle loops and things properly, we really need dominance
503 * information. It would end up basically being the into-SSA
504 * algorithm all over again. It's easier if we just let
505 * lower_vars_to_ssa do that for us instead of repeating it here.
507 struct vtn_value
*val
= vtn_push_value(b
, w
[2], vtn_value_type_ssa
);
509 struct vtn_type
*type
= vtn_value(b
, w
[1], vtn_value_type_type
)->type
;
510 nir_variable
*phi_var
=
511 nir_local_variable_create(b
->nb
.impl
, type
->type
, "phi");
512 _mesa_hash_table_insert(b
->phi_table
, w
, phi_var
);
514 val
->ssa
= vtn_local_load(b
, nir_deref_var_create(b
, phi_var
));
520 vtn_handle_phi_second_pass(struct vtn_builder
*b
, SpvOp opcode
,
521 const uint32_t *w
, unsigned count
)
523 if (opcode
!= SpvOpPhi
)
526 struct hash_entry
*phi_entry
= _mesa_hash_table_search(b
->phi_table
, w
);
528 nir_variable
*phi_var
= phi_entry
->data
;
530 for (unsigned i
= 3; i
< count
; i
+= 2) {
531 struct vtn_block
*pred
=
532 vtn_value(b
, w
[i
+ 1], vtn_value_type_block
)->block
;
534 b
->nb
.cursor
= nir_after_instr(&pred
->end_nop
->instr
);
536 struct vtn_ssa_value
*src
= vtn_ssa_value(b
, w
[i
]);
538 vtn_local_store(b
, src
, nir_deref_var_create(b
, phi_var
));
545 vtn_emit_branch(struct vtn_builder
*b
, enum vtn_branch_type branch_type
,
546 nir_variable
*switch_fall_var
, bool *has_switch_break
)
548 switch (branch_type
) {
549 case vtn_branch_type_switch_break
:
550 nir_store_var(&b
->nb
, switch_fall_var
, nir_imm_int(&b
->nb
, NIR_FALSE
), 1);
551 *has_switch_break
= true;
553 case vtn_branch_type_switch_fallthrough
:
554 break; /* Nothing to do */
555 case vtn_branch_type_loop_break
:
556 nir_jump(&b
->nb
, nir_jump_break
);
558 case vtn_branch_type_loop_continue
:
559 nir_jump(&b
->nb
, nir_jump_continue
);
561 case vtn_branch_type_return
:
562 nir_jump(&b
->nb
, nir_jump_return
);
564 case vtn_branch_type_discard
: {
565 nir_intrinsic_instr
*discard
=
566 nir_intrinsic_instr_create(b
->nb
.shader
, nir_intrinsic_discard
);
567 nir_builder_instr_insert(&b
->nb
, &discard
->instr
);
571 unreachable("Invalid branch type");
576 vtn_emit_cf_list(struct vtn_builder
*b
, struct list_head
*cf_list
,
577 nir_variable
*switch_fall_var
, bool *has_switch_break
,
578 vtn_instruction_handler handler
)
580 list_for_each_entry(struct vtn_cf_node
, node
, cf_list
, link
) {
581 switch (node
->type
) {
582 case vtn_cf_node_type_block
: {
583 struct vtn_block
*block
= (struct vtn_block
*)node
;
585 const uint32_t *block_start
= block
->label
;
586 const uint32_t *block_end
= block
->merge
? block
->merge
:
589 block_start
= vtn_foreach_instruction(b
, block_start
, block_end
,
590 vtn_handle_phis_first_pass
);
592 vtn_foreach_instruction(b
, block_start
, block_end
, handler
);
594 block
->end_nop
= nir_intrinsic_instr_create(b
->nb
.shader
,
596 nir_builder_instr_insert(&b
->nb
, &block
->end_nop
->instr
);
598 if ((*block
->branch
& SpvOpCodeMask
) == SpvOpReturnValue
) {
599 struct vtn_ssa_value
*src
= vtn_ssa_value(b
, block
->branch
[1]);
600 vtn_local_store(b
, src
,
601 nir_deref_var_create(b
, b
->impl
->return_var
));
604 if (block
->branch_type
!= vtn_branch_type_none
) {
605 vtn_emit_branch(b
, block
->branch_type
,
606 switch_fall_var
, has_switch_break
);
612 case vtn_cf_node_type_if
: {
613 struct vtn_if
*vtn_if
= (struct vtn_if
*)node
;
614 bool sw_break
= false;
617 nir_push_if(&b
->nb
, vtn_ssa_value(b
, vtn_if
->condition
)->def
);
618 if (vtn_if
->then_type
== vtn_branch_type_none
) {
619 vtn_emit_cf_list(b
, &vtn_if
->then_body
,
620 switch_fall_var
, &sw_break
, handler
);
622 vtn_emit_branch(b
, vtn_if
->then_type
, switch_fall_var
, &sw_break
);
625 nir_push_else(&b
->nb
, nif
);
626 if (vtn_if
->else_type
== vtn_branch_type_none
) {
627 vtn_emit_cf_list(b
, &vtn_if
->else_body
,
628 switch_fall_var
, &sw_break
, handler
);
630 vtn_emit_branch(b
, vtn_if
->else_type
, switch_fall_var
, &sw_break
);
633 nir_pop_if(&b
->nb
, nif
);
635 /* If we encountered a switch break somewhere inside of the if,
636 * then it would have been handled correctly by calling
637 * emit_cf_list or emit_branch for the interrior. However, we
638 * need to predicate everything following on wether or not we're
642 *has_switch_break
= true;
643 nir_push_if(&b
->nb
, nir_load_var(&b
->nb
, switch_fall_var
));
648 case vtn_cf_node_type_loop
: {
649 struct vtn_loop
*vtn_loop
= (struct vtn_loop
*)node
;
651 nir_loop
*loop
= nir_push_loop(&b
->nb
);
652 vtn_emit_cf_list(b
, &vtn_loop
->body
, NULL
, NULL
, handler
);
654 if (!list_empty(&vtn_loop
->cont_body
)) {
655 /* If we have a non-trivial continue body then we need to put
656 * it at the beginning of the loop with a flag to ensure that
657 * it doesn't get executed in the first iteration.
659 nir_variable
*do_cont
=
660 nir_local_variable_create(b
->nb
.impl
, glsl_bool_type(), "cont");
662 b
->nb
.cursor
= nir_before_cf_node(&loop
->cf_node
);
663 nir_store_var(&b
->nb
, do_cont
, nir_imm_int(&b
->nb
, NIR_FALSE
), 1);
665 b
->nb
.cursor
= nir_before_cf_list(&loop
->body
);
668 nir_push_if(&b
->nb
, nir_load_var(&b
->nb
, do_cont
));
670 vtn_emit_cf_list(b
, &vtn_loop
->cont_body
, NULL
, NULL
, handler
);
672 nir_pop_if(&b
->nb
, cont_if
);
674 nir_store_var(&b
->nb
, do_cont
, nir_imm_int(&b
->nb
, NIR_TRUE
), 1);
676 b
->has_loop_continue
= true;
679 nir_pop_loop(&b
->nb
, loop
);
683 case vtn_cf_node_type_switch
: {
684 struct vtn_switch
*vtn_switch
= (struct vtn_switch
*)node
;
686 /* First, we create a variable to keep track of whether or not the
687 * switch is still going at any given point. Any switch breaks
688 * will set this variable to false.
690 nir_variable
*fall_var
=
691 nir_local_variable_create(b
->nb
.impl
, glsl_bool_type(), "fall");
692 nir_store_var(&b
->nb
, fall_var
, nir_imm_int(&b
->nb
, NIR_FALSE
), 1);
694 /* Next, we gather up all of the conditions. We have to do this
695 * up-front because we also need to build an "any" condition so
696 * that we can use !any for default.
698 const int num_cases
= list_length(&vtn_switch
->cases
);
699 NIR_VLA(nir_ssa_def
*, conditions
, num_cases
);
701 nir_ssa_def
*sel
= vtn_ssa_value(b
, vtn_switch
->selector
)->def
;
702 /* An accumulation of all conditions. Used for the default */
703 nir_ssa_def
*any
= NULL
;
706 list_for_each_entry(struct vtn_case
, cse
, &vtn_switch
->cases
, link
) {
707 if (cse
->is_default
) {
708 conditions
[i
++] = NULL
;
712 nir_ssa_def
*cond
= NULL
;
713 util_dynarray_foreach(&cse
->values
, uint32_t, val
) {
714 nir_ssa_def
*is_val
=
715 nir_ieq(&b
->nb
, sel
, nir_imm_int(&b
->nb
, *val
));
717 cond
= cond
? nir_ior(&b
->nb
, cond
, is_val
) : is_val
;
720 any
= any
? nir_ior(&b
->nb
, any
, cond
) : cond
;
721 conditions
[i
++] = cond
;
723 assert(i
== num_cases
);
725 /* Now we can walk the list of cases and actually emit code */
727 list_for_each_entry(struct vtn_case
, cse
, &vtn_switch
->cases
, link
) {
728 /* Figure out the condition */
729 nir_ssa_def
*cond
= conditions
[i
++];
730 if (cse
->is_default
) {
731 assert(cond
== NULL
);
732 cond
= nir_inot(&b
->nb
, any
);
734 /* Take fallthrough into account */
735 cond
= nir_ior(&b
->nb
, cond
, nir_load_var(&b
->nb
, fall_var
));
737 nir_if
*case_if
= nir_push_if(&b
->nb
, cond
);
739 bool has_break
= false;
740 nir_store_var(&b
->nb
, fall_var
, nir_imm_int(&b
->nb
, NIR_TRUE
), 1);
741 vtn_emit_cf_list(b
, &cse
->body
, fall_var
, &has_break
, handler
);
742 (void)has_break
; /* We don't care */
744 nir_pop_if(&b
->nb
, case_if
);
746 assert(i
== num_cases
);
752 unreachable("Invalid CF node type");
758 vtn_function_emit(struct vtn_builder
*b
, struct vtn_function
*func
,
759 vtn_instruction_handler instruction_handler
)
761 nir_builder_init(&b
->nb
, func
->impl
);
762 b
->nb
.cursor
= nir_after_cf_list(&func
->impl
->body
);
763 b
->has_loop_continue
= false;
764 b
->phi_table
= _mesa_hash_table_create(b
, _mesa_hash_pointer
,
765 _mesa_key_pointer_equal
);
767 vtn_emit_cf_list(b
, &func
->body
, NULL
, NULL
, instruction_handler
);
769 vtn_foreach_instruction(b
, func
->start_block
->label
, func
->end
,
770 vtn_handle_phi_second_pass
);
772 /* Continue blocks for loops get inserted before the body of the loop
773 * but instructions in the continue may use SSA defs in the loop body.
774 * Therefore, we need to repair SSA to insert the needed phi nodes.
776 if (b
->has_loop_continue
)
777 nir_repair_ssa_impl(func
->impl
);