nir_builder.h revision 01e04c3f
1/*
2 * Copyright © 2014-2015 Broadcom
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 DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24#ifndef NIR_BUILDER_H
25#define NIR_BUILDER_H
26
27#include "nir_control_flow.h"
28#include "util/half_float.h"
29
30struct exec_list;
31
32typedef struct nir_builder {
33   nir_cursor cursor;
34
35   /* Whether new ALU instructions will be marked "exact" */
36   bool exact;
37
38   nir_shader *shader;
39   nir_function_impl *impl;
40} nir_builder;
41
42static inline void
43nir_builder_init(nir_builder *build, nir_function_impl *impl)
44{
45   memset(build, 0, sizeof(*build));
46   build->exact = false;
47   build->impl = impl;
48   build->shader = impl->function->shader;
49}
50
51static inline void
52nir_builder_init_simple_shader(nir_builder *build, void *mem_ctx,
53                               gl_shader_stage stage,
54                               const nir_shader_compiler_options *options)
55{
56   build->shader = nir_shader_create(mem_ctx, stage, options, NULL);
57   nir_function *func = nir_function_create(build->shader, "main");
58   build->exact = false;
59   build->impl = nir_function_impl_create(func);
60   build->cursor = nir_after_cf_list(&build->impl->body);
61}
62
63static inline void
64nir_builder_instr_insert(nir_builder *build, nir_instr *instr)
65{
66   nir_instr_insert(build->cursor, instr);
67
68   /* Move the cursor forward. */
69   build->cursor = nir_after_instr(instr);
70}
71
72static inline nir_instr *
73nir_builder_last_instr(nir_builder *build)
74{
75   assert(build->cursor.option == nir_cursor_after_instr);
76   return build->cursor.instr;
77}
78
79static inline void
80nir_builder_cf_insert(nir_builder *build, nir_cf_node *cf)
81{
82   nir_cf_node_insert(build->cursor, cf);
83}
84
85static inline bool
86nir_builder_is_inside_cf(nir_builder *build, nir_cf_node *cf_node)
87{
88   nir_block *block = nir_cursor_current_block(build->cursor);
89   for (nir_cf_node *n = &block->cf_node; n; n = n->parent) {
90      if (n == cf_node)
91         return true;
92   }
93   return false;
94}
95
96static inline nir_if *
97nir_push_if(nir_builder *build, nir_ssa_def *condition)
98{
99   nir_if *nif = nir_if_create(build->shader);
100   nif->condition = nir_src_for_ssa(condition);
101   nir_builder_cf_insert(build, &nif->cf_node);
102   build->cursor = nir_before_cf_list(&nif->then_list);
103   return nif;
104}
105
106static inline nir_if *
107nir_push_else(nir_builder *build, nir_if *nif)
108{
109   if (nif) {
110      assert(nir_builder_is_inside_cf(build, &nif->cf_node));
111   } else {
112      nir_block *block = nir_cursor_current_block(build->cursor);
113      nif = nir_cf_node_as_if(block->cf_node.parent);
114   }
115   build->cursor = nir_before_cf_list(&nif->else_list);
116   return nif;
117}
118
119static inline void
120nir_pop_if(nir_builder *build, nir_if *nif)
121{
122   if (nif) {
123      assert(nir_builder_is_inside_cf(build, &nif->cf_node));
124   } else {
125      nir_block *block = nir_cursor_current_block(build->cursor);
126      nif = nir_cf_node_as_if(block->cf_node.parent);
127   }
128   build->cursor = nir_after_cf_node(&nif->cf_node);
129}
130
131static inline nir_ssa_def *
132nir_if_phi(nir_builder *build, nir_ssa_def *then_def, nir_ssa_def *else_def)
133{
134   nir_block *block = nir_cursor_current_block(build->cursor);
135   nir_if *nif = nir_cf_node_as_if(nir_cf_node_prev(&block->cf_node));
136
137   nir_phi_instr *phi = nir_phi_instr_create(build->shader);
138
139   nir_phi_src *src = ralloc(phi, nir_phi_src);
140   src->pred = nir_if_last_then_block(nif);
141   src->src = nir_src_for_ssa(then_def);
142   exec_list_push_tail(&phi->srcs, &src->node);
143
144   src = ralloc(phi, nir_phi_src);
145   src->pred = nir_if_last_else_block(nif);
146   src->src = nir_src_for_ssa(else_def);
147   exec_list_push_tail(&phi->srcs, &src->node);
148
149   assert(then_def->num_components == else_def->num_components);
150   assert(then_def->bit_size == else_def->bit_size);
151   nir_ssa_dest_init(&phi->instr, &phi->dest,
152                     then_def->num_components, then_def->bit_size, NULL);
153
154   nir_builder_instr_insert(build, &phi->instr);
155
156   return &phi->dest.ssa;
157}
158
159static inline nir_loop *
160nir_push_loop(nir_builder *build)
161{
162   nir_loop *loop = nir_loop_create(build->shader);
163   nir_builder_cf_insert(build, &loop->cf_node);
164   build->cursor = nir_before_cf_list(&loop->body);
165   return loop;
166}
167
168static inline void
169nir_pop_loop(nir_builder *build, nir_loop *loop)
170{
171   if (loop) {
172      assert(nir_builder_is_inside_cf(build, &loop->cf_node));
173   } else {
174      nir_block *block = nir_cursor_current_block(build->cursor);
175      loop = nir_cf_node_as_loop(block->cf_node.parent);
176   }
177   build->cursor = nir_after_cf_node(&loop->cf_node);
178}
179
180static inline nir_ssa_def *
181nir_ssa_undef(nir_builder *build, unsigned num_components, unsigned bit_size)
182{
183   nir_ssa_undef_instr *undef =
184      nir_ssa_undef_instr_create(build->shader, num_components, bit_size);
185   if (!undef)
186      return NULL;
187
188   nir_instr_insert(nir_before_cf_list(&build->impl->body), &undef->instr);
189
190   return &undef->def;
191}
192
193static inline nir_ssa_def *
194nir_build_imm(nir_builder *build, unsigned num_components,
195              unsigned bit_size, nir_const_value value)
196{
197   nir_load_const_instr *load_const =
198      nir_load_const_instr_create(build->shader, num_components, bit_size);
199   if (!load_const)
200      return NULL;
201
202   load_const->value = value;
203
204   nir_builder_instr_insert(build, &load_const->instr);
205
206   return &load_const->def;
207}
208
209static inline nir_ssa_def *
210nir_imm_bool(nir_builder *build, bool x)
211{
212   nir_const_value v;
213
214   memset(&v, 0, sizeof(v));
215   v.u32[0] = x ? NIR_TRUE : NIR_FALSE;
216
217   return nir_build_imm(build, 1, 32, v);
218}
219
220static inline nir_ssa_def *
221nir_imm_true(nir_builder *build)
222{
223   return nir_imm_bool(build, true);
224}
225
226static inline nir_ssa_def *
227nir_imm_false(nir_builder *build)
228{
229   return nir_imm_bool(build, false);
230}
231
232static inline nir_ssa_def *
233nir_imm_float16(nir_builder *build, float x)
234{
235   nir_const_value v;
236
237   memset(&v, 0, sizeof(v));
238   v.u16[0] = _mesa_float_to_half(x);
239
240   return nir_build_imm(build, 1, 16, v);
241}
242
243static inline nir_ssa_def *
244nir_imm_float(nir_builder *build, float x)
245{
246   nir_const_value v;
247
248   memset(&v, 0, sizeof(v));
249   v.f32[0] = x;
250
251   return nir_build_imm(build, 1, 32, v);
252}
253
254static inline nir_ssa_def *
255nir_imm_double(nir_builder *build, double x)
256{
257   nir_const_value v;
258
259   memset(&v, 0, sizeof(v));
260   v.f64[0] = x;
261
262   return nir_build_imm(build, 1, 64, v);
263}
264
265static inline nir_ssa_def *
266nir_imm_floatN_t(nir_builder *build, double x, unsigned bit_size)
267{
268   switch (bit_size) {
269   case 16:
270      return nir_imm_float16(build, x);
271   case 32:
272      return nir_imm_float(build, x);
273   case 64:
274      return nir_imm_double(build, x);
275   }
276
277   unreachable("unknown float immediate bit size");
278}
279
280static inline nir_ssa_def *
281nir_imm_vec4(nir_builder *build, float x, float y, float z, float w)
282{
283   nir_const_value v;
284
285   memset(&v, 0, sizeof(v));
286   v.f32[0] = x;
287   v.f32[1] = y;
288   v.f32[2] = z;
289   v.f32[3] = w;
290
291   return nir_build_imm(build, 4, 32, v);
292}
293
294static inline nir_ssa_def *
295nir_imm_ivec2(nir_builder *build, int x, int y)
296{
297   nir_const_value v;
298
299   memset(&v, 0, sizeof(v));
300   v.i32[0] = x;
301   v.i32[1] = y;
302
303   return nir_build_imm(build, 2, 32, v);
304}
305
306static inline nir_ssa_def *
307nir_imm_int(nir_builder *build, int x)
308{
309   nir_const_value v;
310
311   memset(&v, 0, sizeof(v));
312   v.i32[0] = x;
313
314   return nir_build_imm(build, 1, 32, v);
315}
316
317static inline nir_ssa_def *
318nir_imm_int64(nir_builder *build, int64_t x)
319{
320   nir_const_value v;
321
322   memset(&v, 0, sizeof(v));
323   v.i64[0] = x;
324
325   return nir_build_imm(build, 1, 64, v);
326}
327
328static inline nir_ssa_def *
329nir_imm_intN_t(nir_builder *build, uint64_t x, unsigned bit_size)
330{
331   nir_const_value v;
332
333   memset(&v, 0, sizeof(v));
334   assert(bit_size <= 64);
335   v.i64[0] = x & (~0ull >> (64 - bit_size));
336
337   return nir_build_imm(build, 1, bit_size, v);
338}
339
340static inline nir_ssa_def *
341nir_imm_ivec4(nir_builder *build, int x, int y, int z, int w)
342{
343   nir_const_value v;
344
345   memset(&v, 0, sizeof(v));
346   v.i32[0] = x;
347   v.i32[1] = y;
348   v.i32[2] = z;
349   v.i32[3] = w;
350
351   return nir_build_imm(build, 4, 32, v);
352}
353
354static inline nir_ssa_def *
355nir_build_alu(nir_builder *build, nir_op op, nir_ssa_def *src0,
356              nir_ssa_def *src1, nir_ssa_def *src2, nir_ssa_def *src3)
357{
358   const nir_op_info *op_info = &nir_op_infos[op];
359   nir_alu_instr *instr = nir_alu_instr_create(build->shader, op);
360   if (!instr)
361      return NULL;
362
363   instr->exact = build->exact;
364
365   instr->src[0].src = nir_src_for_ssa(src0);
366   if (src1)
367      instr->src[1].src = nir_src_for_ssa(src1);
368   if (src2)
369      instr->src[2].src = nir_src_for_ssa(src2);
370   if (src3)
371      instr->src[3].src = nir_src_for_ssa(src3);
372
373   /* Guess the number of components the destination temporary should have
374    * based on our input sizes, if it's not fixed for the op.
375    */
376   unsigned num_components = op_info->output_size;
377   if (num_components == 0) {
378      for (unsigned i = 0; i < op_info->num_inputs; i++) {
379         if (op_info->input_sizes[i] == 0)
380            num_components = MAX2(num_components,
381                                  instr->src[i].src.ssa->num_components);
382      }
383   }
384   assert(num_components != 0);
385
386   /* Figure out the bitwidth based on the source bitwidth if the instruction
387    * is variable-width.
388    */
389   unsigned bit_size = nir_alu_type_get_type_size(op_info->output_type);
390   if (bit_size == 0) {
391      for (unsigned i = 0; i < op_info->num_inputs; i++) {
392         unsigned src_bit_size = instr->src[i].src.ssa->bit_size;
393         if (nir_alu_type_get_type_size(op_info->input_types[i]) == 0) {
394            if (bit_size)
395               assert(src_bit_size == bit_size);
396            else
397               bit_size = src_bit_size;
398         } else {
399            assert(src_bit_size ==
400               nir_alu_type_get_type_size(op_info->input_types[i]));
401         }
402      }
403   }
404
405   /* When in doubt, assume 32. */
406   if (bit_size == 0)
407      bit_size = 32;
408
409   /* Make sure we don't swizzle from outside of our source vector (like if a
410    * scalar value was passed into a multiply with a vector).
411    */
412   for (unsigned i = 0; i < op_info->num_inputs; i++) {
413      for (unsigned j = instr->src[i].src.ssa->num_components;
414           j < NIR_MAX_VEC_COMPONENTS; j++) {
415         instr->src[i].swizzle[j] = instr->src[i].src.ssa->num_components - 1;
416      }
417   }
418
419   nir_ssa_dest_init(&instr->instr, &instr->dest.dest, num_components,
420                     bit_size, NULL);
421   instr->dest.write_mask = (1 << num_components) - 1;
422
423   nir_builder_instr_insert(build, &instr->instr);
424
425   return &instr->dest.dest.ssa;
426}
427
428#include "nir_builder_opcodes.h"
429
430static inline nir_ssa_def *
431nir_vec(nir_builder *build, nir_ssa_def **comp, unsigned num_components)
432{
433   switch (num_components) {
434   case 4:
435      return nir_vec4(build, comp[0], comp[1], comp[2], comp[3]);
436   case 3:
437      return nir_vec3(build, comp[0], comp[1], comp[2]);
438   case 2:
439      return nir_vec2(build, comp[0], comp[1]);
440   case 1:
441      return comp[0];
442   default:
443      unreachable("bad component count");
444      return NULL;
445   }
446}
447
448/**
449 * Similar to nir_fmov, but takes a nir_alu_src instead of a nir_ssa_def.
450 */
451static inline nir_ssa_def *
452nir_fmov_alu(nir_builder *build, nir_alu_src src, unsigned num_components)
453{
454   nir_alu_instr *mov = nir_alu_instr_create(build->shader, nir_op_fmov);
455   nir_ssa_dest_init(&mov->instr, &mov->dest.dest, num_components,
456                     nir_src_bit_size(src.src), NULL);
457   mov->exact = build->exact;
458   mov->dest.write_mask = (1 << num_components) - 1;
459   mov->src[0] = src;
460   nir_builder_instr_insert(build, &mov->instr);
461
462   return &mov->dest.dest.ssa;
463}
464
465static inline nir_ssa_def *
466nir_imov_alu(nir_builder *build, nir_alu_src src, unsigned num_components)
467{
468   nir_alu_instr *mov = nir_alu_instr_create(build->shader, nir_op_imov);
469   nir_ssa_dest_init(&mov->instr, &mov->dest.dest, num_components,
470                     nir_src_bit_size(src.src), NULL);
471   mov->exact = build->exact;
472   mov->dest.write_mask = (1 << num_components) - 1;
473   mov->src[0] = src;
474   nir_builder_instr_insert(build, &mov->instr);
475
476   return &mov->dest.dest.ssa;
477}
478
479/**
480 * Construct an fmov or imov that reswizzles the source's components.
481 */
482static inline nir_ssa_def *
483nir_swizzle(nir_builder *build, nir_ssa_def *src, const unsigned *swiz,
484            unsigned num_components, bool use_fmov)
485{
486   assert(num_components <= NIR_MAX_VEC_COMPONENTS);
487   nir_alu_src alu_src = { NIR_SRC_INIT };
488   alu_src.src = nir_src_for_ssa(src);
489   for (unsigned i = 0; i < num_components && i < NIR_MAX_VEC_COMPONENTS; i++)
490      alu_src.swizzle[i] = swiz[i];
491
492   return use_fmov ? nir_fmov_alu(build, alu_src, num_components) :
493                     nir_imov_alu(build, alu_src, num_components);
494}
495
496/* Selects the right fdot given the number of components in each source. */
497static inline nir_ssa_def *
498nir_fdot(nir_builder *build, nir_ssa_def *src0, nir_ssa_def *src1)
499{
500   assert(src0->num_components == src1->num_components);
501   switch (src0->num_components) {
502   case 1: return nir_fmul(build, src0, src1);
503   case 2: return nir_fdot2(build, src0, src1);
504   case 3: return nir_fdot3(build, src0, src1);
505   case 4: return nir_fdot4(build, src0, src1);
506   default:
507      unreachable("bad component size");
508   }
509
510   return NULL;
511}
512
513static inline nir_ssa_def *
514nir_bany_inequal(nir_builder *b, nir_ssa_def *src0, nir_ssa_def *src1)
515{
516   switch (src0->num_components) {
517   case 1: return nir_ine(b, src0, src1);
518   case 2: return nir_bany_inequal2(b, src0, src1);
519   case 3: return nir_bany_inequal3(b, src0, src1);
520   case 4: return nir_bany_inequal4(b, src0, src1);
521   default:
522      unreachable("bad component size");
523   }
524}
525
526static inline nir_ssa_def *
527nir_bany(nir_builder *b, nir_ssa_def *src)
528{
529   return nir_bany_inequal(b, src, nir_imm_false(b));
530}
531
532static inline nir_ssa_def *
533nir_channel(nir_builder *b, nir_ssa_def *def, unsigned c)
534{
535   return nir_swizzle(b, def, &c, 1, false);
536}
537
538static inline nir_ssa_def *
539nir_channels(nir_builder *b, nir_ssa_def *def, nir_component_mask_t mask)
540{
541   unsigned num_channels = 0, swizzle[NIR_MAX_VEC_COMPONENTS] = { 0 };
542
543   for (unsigned i = 0; i < NIR_MAX_VEC_COMPONENTS; i++) {
544      if ((mask & (1 << i)) == 0)
545         continue;
546      swizzle[num_channels++] = i;
547   }
548
549   return nir_swizzle(b, def, swizzle, num_channels, false);
550}
551
552/**
553 * Turns a nir_src into a nir_ssa_def * so it can be passed to
554 * nir_build_alu()-based builder calls.
555 *
556 * See nir_ssa_for_alu_src() for alu instructions.
557 */
558static inline nir_ssa_def *
559nir_ssa_for_src(nir_builder *build, nir_src src, int num_components)
560{
561   if (src.is_ssa && src.ssa->num_components == num_components)
562      return src.ssa;
563
564   nir_alu_src alu = { NIR_SRC_INIT };
565   alu.src = src;
566   for (int j = 0; j < 4; j++)
567      alu.swizzle[j] = j;
568
569   return nir_imov_alu(build, alu, num_components);
570}
571
572/**
573 * Similar to nir_ssa_for_src(), but for alu srcs, respecting the
574 * nir_alu_src's swizzle.
575 */
576static inline nir_ssa_def *
577nir_ssa_for_alu_src(nir_builder *build, nir_alu_instr *instr, unsigned srcn)
578{
579   static uint8_t trivial_swizzle[NIR_MAX_VEC_COMPONENTS];
580   for (int i = 0; i < NIR_MAX_VEC_COMPONENTS; ++i)
581      trivial_swizzle[i] = i;
582   nir_alu_src *src = &instr->src[srcn];
583   unsigned num_components = nir_ssa_alu_instr_src_components(instr, srcn);
584
585   if (src->src.is_ssa && (src->src.ssa->num_components == num_components) &&
586       !src->abs && !src->negate &&
587       (memcmp(src->swizzle, trivial_swizzle, num_components) == 0))
588      return src->src.ssa;
589
590   return nir_imov_alu(build, *src, num_components);
591}
592
593static inline nir_deref_instr *
594nir_build_deref_var(nir_builder *build, nir_variable *var)
595{
596   nir_deref_instr *deref =
597      nir_deref_instr_create(build->shader, nir_deref_type_var);
598
599   deref->mode = var->data.mode;
600   deref->type = var->type;
601   deref->var = var;
602
603   nir_ssa_dest_init(&deref->instr, &deref->dest, 1, 32, NULL);
604
605   nir_builder_instr_insert(build, &deref->instr);
606
607   return deref;
608}
609
610static inline nir_deref_instr *
611nir_build_deref_array(nir_builder *build, nir_deref_instr *parent,
612                      nir_ssa_def *index)
613{
614   assert(glsl_type_is_array(parent->type) ||
615          glsl_type_is_matrix(parent->type) ||
616          glsl_type_is_vector(parent->type));
617
618   nir_deref_instr *deref =
619      nir_deref_instr_create(build->shader, nir_deref_type_array);
620
621   deref->mode = parent->mode;
622   deref->type = glsl_get_array_element(parent->type);
623   deref->parent = nir_src_for_ssa(&parent->dest.ssa);
624   deref->arr.index = nir_src_for_ssa(index);
625
626   nir_ssa_dest_init(&deref->instr, &deref->dest,
627                     parent->dest.ssa.num_components,
628                     parent->dest.ssa.bit_size, NULL);
629
630   nir_builder_instr_insert(build, &deref->instr);
631
632   return deref;
633}
634
635static inline nir_deref_instr *
636nir_build_deref_array_wildcard(nir_builder *build, nir_deref_instr *parent)
637{
638   assert(glsl_type_is_array(parent->type) ||
639          glsl_type_is_matrix(parent->type));
640
641   nir_deref_instr *deref =
642      nir_deref_instr_create(build->shader, nir_deref_type_array_wildcard);
643
644   deref->mode = parent->mode;
645   deref->type = glsl_get_array_element(parent->type);
646   deref->parent = nir_src_for_ssa(&parent->dest.ssa);
647
648   nir_ssa_dest_init(&deref->instr, &deref->dest,
649                     parent->dest.ssa.num_components,
650                     parent->dest.ssa.bit_size, NULL);
651
652   nir_builder_instr_insert(build, &deref->instr);
653
654   return deref;
655}
656
657static inline nir_deref_instr *
658nir_build_deref_struct(nir_builder *build, nir_deref_instr *parent,
659                       unsigned index)
660{
661   assert(glsl_type_is_struct(parent->type));
662
663   nir_deref_instr *deref =
664      nir_deref_instr_create(build->shader, nir_deref_type_struct);
665
666   deref->mode = parent->mode;
667   deref->type = glsl_get_struct_field(parent->type, index);
668   deref->parent = nir_src_for_ssa(&parent->dest.ssa);
669   deref->strct.index = index;
670
671   nir_ssa_dest_init(&deref->instr, &deref->dest,
672                     parent->dest.ssa.num_components,
673                     parent->dest.ssa.bit_size, NULL);
674
675   nir_builder_instr_insert(build, &deref->instr);
676
677   return deref;
678}
679
680static inline nir_deref_instr *
681nir_build_deref_cast(nir_builder *build, nir_ssa_def *parent,
682                     nir_variable_mode mode, const struct glsl_type *type)
683{
684   nir_deref_instr *deref =
685      nir_deref_instr_create(build->shader, nir_deref_type_cast);
686
687   deref->mode = mode;
688   deref->type = type;
689   deref->parent = nir_src_for_ssa(parent);
690
691   nir_ssa_dest_init(&deref->instr, &deref->dest,
692                     parent->num_components, parent->bit_size, NULL);
693
694   nir_builder_instr_insert(build, &deref->instr);
695
696   return deref;
697}
698
699/** Returns a deref that follows another but starting from the given parent
700 *
701 * The new deref will be the same type and take the same array or struct index
702 * as the leader deref but it may have a different parent.  This is very
703 * useful for walking deref paths.
704 */
705static inline nir_deref_instr *
706nir_build_deref_follower(nir_builder *b, nir_deref_instr *parent,
707                         nir_deref_instr *leader)
708{
709   /* If the derefs would have the same parent, don't make a new one */
710   assert(leader->parent.is_ssa);
711   if (leader->parent.ssa == &parent->dest.ssa)
712      return leader;
713
714   UNUSED nir_deref_instr *leader_parent = nir_src_as_deref(leader->parent);
715
716   switch (leader->deref_type) {
717   case nir_deref_type_var:
718      unreachable("A var dereference cannot have a parent");
719      break;
720
721   case nir_deref_type_array:
722   case nir_deref_type_array_wildcard:
723      assert(glsl_type_is_matrix(parent->type) ||
724             glsl_type_is_array(parent->type));
725      assert(glsl_get_length(parent->type) ==
726             glsl_get_length(leader_parent->type));
727
728      if (leader->deref_type == nir_deref_type_array) {
729         assert(leader->arr.index.is_ssa);
730         return nir_build_deref_array(b, parent, leader->arr.index.ssa);
731      } else {
732         return nir_build_deref_array_wildcard(b, parent);
733      }
734
735   case nir_deref_type_struct:
736      assert(glsl_type_is_struct(parent->type));
737      assert(glsl_get_length(parent->type) ==
738             glsl_get_length(leader_parent->type));
739
740      return nir_build_deref_struct(b, parent, leader->strct.index);
741
742   default:
743      unreachable("Invalid deref instruction type");
744   }
745}
746
747static inline nir_ssa_def *
748nir_load_reg(nir_builder *build, nir_register *reg)
749{
750   return nir_ssa_for_src(build, nir_src_for_reg(reg), reg->num_components);
751}
752
753static inline nir_ssa_def *
754nir_load_deref(nir_builder *build, nir_deref_instr *deref)
755{
756   nir_intrinsic_instr *load =
757      nir_intrinsic_instr_create(build->shader, nir_intrinsic_load_deref);
758   load->num_components = glsl_get_vector_elements(deref->type);
759   load->src[0] = nir_src_for_ssa(&deref->dest.ssa);
760   nir_ssa_dest_init(&load->instr, &load->dest, load->num_components,
761                     glsl_get_bit_size(deref->type), NULL);
762   nir_builder_instr_insert(build, &load->instr);
763   return &load->dest.ssa;
764}
765
766static inline void
767nir_store_deref(nir_builder *build, nir_deref_instr *deref,
768                nir_ssa_def *value, unsigned writemask)
769{
770   nir_intrinsic_instr *store =
771      nir_intrinsic_instr_create(build->shader, nir_intrinsic_store_deref);
772   store->num_components = glsl_get_vector_elements(deref->type);
773   store->src[0] = nir_src_for_ssa(&deref->dest.ssa);
774   store->src[1] = nir_src_for_ssa(value);
775   nir_intrinsic_set_write_mask(store,
776                                writemask & ((1 << store->num_components) - 1));
777   nir_builder_instr_insert(build, &store->instr);
778}
779
780static inline void
781nir_copy_deref(nir_builder *build, nir_deref_instr *dest, nir_deref_instr *src)
782{
783   nir_intrinsic_instr *copy =
784      nir_intrinsic_instr_create(build->shader, nir_intrinsic_copy_deref);
785   copy->src[0] = nir_src_for_ssa(&dest->dest.ssa);
786   copy->src[1] = nir_src_for_ssa(&src->dest.ssa);
787   nir_builder_instr_insert(build, &copy->instr);
788}
789
790static inline nir_ssa_def *
791nir_load_var(nir_builder *build, nir_variable *var)
792{
793   return nir_load_deref(build, nir_build_deref_var(build, var));
794}
795
796static inline void
797nir_store_var(nir_builder *build, nir_variable *var, nir_ssa_def *value,
798              unsigned writemask)
799{
800   nir_store_deref(build, nir_build_deref_var(build, var), value, writemask);
801}
802
803static inline void
804nir_copy_var(nir_builder *build, nir_variable *dest, nir_variable *src)
805{
806   nir_copy_deref(build, nir_build_deref_var(build, dest),
807                         nir_build_deref_var(build, src));
808}
809
810static inline nir_ssa_def *
811nir_load_param(nir_builder *build, uint32_t param_idx)
812{
813   assert(param_idx < build->impl->function->num_params);
814   nir_parameter *param = &build->impl->function->params[param_idx];
815
816   nir_intrinsic_instr *load =
817      nir_intrinsic_instr_create(build->shader, nir_intrinsic_load_param);
818   nir_intrinsic_set_param_idx(load, param_idx);
819   load->num_components = param->num_components;
820   nir_ssa_dest_init(&load->instr, &load->dest,
821                     param->num_components, param->bit_size, NULL);
822   nir_builder_instr_insert(build, &load->instr);
823   return &load->dest.ssa;
824}
825
826#include "nir_builder_opcodes.h"
827
828static inline nir_ssa_def *
829nir_load_barycentric(nir_builder *build, nir_intrinsic_op op,
830                     unsigned interp_mode)
831{
832   nir_intrinsic_instr *bary = nir_intrinsic_instr_create(build->shader, op);
833   nir_ssa_dest_init(&bary->instr, &bary->dest, 2, 32, NULL);
834   nir_intrinsic_set_interp_mode(bary, interp_mode);
835   nir_builder_instr_insert(build, &bary->instr);
836   return &bary->dest.ssa;
837}
838
839static inline void
840nir_jump(nir_builder *build, nir_jump_type jump_type)
841{
842   nir_jump_instr *jump = nir_jump_instr_create(build->shader, jump_type);
843   nir_builder_instr_insert(build, &jump->instr);
844}
845
846static inline nir_ssa_def *
847nir_compare_func(nir_builder *b, enum compare_func func,
848                 nir_ssa_def *src0, nir_ssa_def *src1)
849{
850   switch (func) {
851   case COMPARE_FUNC_NEVER:
852      return nir_imm_int(b, 0);
853   case COMPARE_FUNC_ALWAYS:
854      return nir_imm_int(b, ~0);
855   case COMPARE_FUNC_EQUAL:
856      return nir_feq(b, src0, src1);
857   case COMPARE_FUNC_NOTEQUAL:
858      return nir_fne(b, src0, src1);
859   case COMPARE_FUNC_GREATER:
860      return nir_flt(b, src1, src0);
861   case COMPARE_FUNC_GEQUAL:
862      return nir_fge(b, src0, src1);
863   case COMPARE_FUNC_LESS:
864      return nir_flt(b, src0, src1);
865   case COMPARE_FUNC_LEQUAL:
866      return nir_fge(b, src1, src0);
867   }
868   unreachable("bad compare func");
869}
870
871#endif /* NIR_BUILDER_H */
872