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1 /*
2  * Copyright © Microsoft 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 DEALINGS
21  * IN THE SOFTWARE.
22  */
23 
24 #include "d3d12_compiler.h"
25 #include "d3d12_context.h"
26 #include "d3d12_debug.h"
27 #include "d3d12_screen.h"
28 
29 #include "nir.h"
30 #include "compiler/nir/nir_builder.h"
31 #include "compiler/nir/nir_builtin_builder.h"
32 
33 #include "util/u_memory.h"
34 #include "util/u_simple_shaders.h"
35 
36 static nir_def *
nir_cull_face(nir_builder * b,nir_variable * vertices,bool ccw)37 nir_cull_face(nir_builder *b, nir_variable *vertices, bool ccw)
38 {
39    nir_def *v0 =
40        nir_load_deref(b, nir_build_deref_array(b, nir_build_deref_var(b, vertices), nir_imm_int(b, 0)));
41    nir_def *v1 =
42        nir_load_deref(b, nir_build_deref_array(b, nir_build_deref_var(b, vertices), nir_imm_int(b, 1)));
43    nir_def *v2 =
44        nir_load_deref(b, nir_build_deref_array(b, nir_build_deref_var(b, vertices), nir_imm_int(b, 2)));
45 
46    nir_def *dir = nir_fdot(b, nir_cross4(b, nir_fsub(b, v1, v0),
47                                                nir_fsub(b, v2, v0)),
48                                    nir_imm_vec4(b, 0.0, 0.0, -1.0, 0.0));
49    if (ccw)
50        return nir_fle_imm(b, dir, 0.0f);
51    else
52        return nir_fgt_imm(b, dir, 0.0f);
53 }
54 
55 static void
copy_vars(nir_builder * b,nir_deref_instr * dst,nir_deref_instr * src)56 copy_vars(nir_builder *b, nir_deref_instr *dst, nir_deref_instr *src)
57 {
58    assert(glsl_get_bare_type(dst->type) == glsl_get_bare_type(src->type));
59    if (glsl_type_is_struct(dst->type)) {
60       for (unsigned i = 0; i < glsl_get_length(dst->type); ++i) {
61          copy_vars(b, nir_build_deref_struct(b, dst, i), nir_build_deref_struct(b, src, i));
62       }
63    } else if (glsl_type_is_array_or_matrix(dst->type)) {
64       copy_vars(b, nir_build_deref_array_wildcard(b, dst), nir_build_deref_array_wildcard(b, src));
65    } else {
66       nir_copy_deref(b, dst, src);
67    }
68 }
69 
70 static d3d12_shader_selector*
d3d12_make_passthrough_gs(struct d3d12_context * ctx,struct d3d12_gs_variant_key * key)71 d3d12_make_passthrough_gs(struct d3d12_context *ctx, struct d3d12_gs_variant_key *key)
72 {
73    struct d3d12_shader_selector *gs;
74    uint64_t varyings = key->varyings->mask;
75    nir_shader *nir;
76    struct pipe_shader_state templ;
77 
78    nir_builder b = nir_builder_init_simple_shader(MESA_SHADER_GEOMETRY,
79                                                   &d3d12_screen(ctx->base.screen)->nir_options,
80                                                   "passthrough");
81 
82    nir = b.shader;
83    nir->info.inputs_read = varyings;
84    nir->info.outputs_written = varyings;
85    nir->info.gs.input_primitive = MESA_PRIM_POINTS;
86    nir->info.gs.output_primitive = MESA_PRIM_POINTS;
87    nir->info.gs.vertices_in = 1;
88    nir->info.gs.vertices_out = 1;
89    nir->info.gs.invocations = 1;
90    nir->info.gs.active_stream_mask = 1;
91 
92    /* Copy inputs to outputs. */
93    while (varyings) {
94       char tmp[100];
95       const int i = u_bit_scan64(&varyings);
96 
97       unsigned frac_slots = key->varyings->slots[i].location_frac_mask;
98       while (frac_slots) {
99          nir_variable *in, *out;
100          int j = u_bit_scan(&frac_slots);
101 
102          snprintf(tmp, ARRAY_SIZE(tmp), "in_%d", key->varyings->slots[i].vars[j].driver_location);
103          in = nir_variable_create(nir,
104                                   nir_var_shader_in,
105                                   glsl_array_type(key->varyings->slots[i].types[j], 1, false),
106                                   tmp);
107          in->data.location = i;
108          in->data.location_frac = j;
109          in->data.driver_location = key->varyings->slots[i].vars[j].driver_location;
110          in->data.interpolation = key->varyings->slots[i].vars[j].interpolation;
111          in->data.compact = key->varyings->slots[i].vars[j].compact;
112 
113          snprintf(tmp, ARRAY_SIZE(tmp), "out_%d", key->varyings->slots[i].vars[j].driver_location);
114          out = nir_variable_create(nir,
115                                    nir_var_shader_out,
116                                    key->varyings->slots[i].types[j],
117                                    tmp);
118          out->data.location = i;
119          out->data.location_frac = j;
120          out->data.driver_location = key->varyings->slots[i].vars[j].driver_location;
121          out->data.interpolation = key->varyings->slots[i].vars[j].interpolation;
122          out->data.compact = key->varyings->slots[i].vars[j].compact;
123 
124          nir_deref_instr *in_value = nir_build_deref_array(&b, nir_build_deref_var(&b, in),
125                                                                nir_imm_int(&b, 0));
126          copy_vars(&b, nir_build_deref_var(&b, out), in_value);
127       }
128    }
129 
130    nir_emit_vertex(&b, 0);
131    nir_end_primitive(&b, 0);
132 
133    NIR_PASS_V(nir, nir_lower_var_copies);
134    nir_validate_shader(nir, "in d3d12_create_passthrough_gs");
135 
136    templ.type = PIPE_SHADER_IR_NIR;
137    templ.ir.nir = nir;
138    templ.stream_output.num_outputs = 0;
139 
140    gs = d3d12_create_shader(ctx, PIPE_SHADER_GEOMETRY, &templ);
141 
142    return gs;
143 }
144 
145 struct emit_primitives_context
146 {
147    struct d3d12_context *ctx;
148    nir_builder b;
149 
150    unsigned num_vars;
151    nir_variable *in[VARYING_SLOT_MAX * 4];
152    nir_variable *out[VARYING_SLOT_MAX * 4];
153    nir_variable *front_facing_var;
154 
155    nir_loop *loop;
156    nir_deref_instr *loop_index_deref;
157    nir_def *loop_index;
158    nir_def *edgeflag_cmp;
159    nir_def *front_facing;
160 };
161 
162 static bool
d3d12_begin_emit_primitives_gs(struct emit_primitives_context * emit_ctx,struct d3d12_context * ctx,struct d3d12_gs_variant_key * key,enum mesa_prim output_primitive,unsigned vertices_out)163 d3d12_begin_emit_primitives_gs(struct emit_primitives_context *emit_ctx,
164                                struct d3d12_context *ctx,
165                                struct d3d12_gs_variant_key *key,
166                                enum mesa_prim output_primitive,
167                                unsigned vertices_out)
168 {
169    nir_builder *b = &emit_ctx->b;
170    nir_variable *edgeflag_var = NULL;
171    nir_variable *pos_var = NULL;
172    uint64_t varyings = key->varyings->mask;
173 
174    emit_ctx->ctx = ctx;
175 
176    emit_ctx->b = nir_builder_init_simple_shader(MESA_SHADER_GEOMETRY,
177                                                 &d3d12_screen(ctx->base.screen)->nir_options,
178                                                 "edgeflags");
179 
180    nir_shader *nir = b->shader;
181    nir->info.inputs_read = varyings;
182    nir->info.outputs_written = varyings;
183    nir->info.gs.input_primitive = MESA_PRIM_TRIANGLES;
184    nir->info.gs.output_primitive = output_primitive;
185    nir->info.gs.vertices_in = 3;
186    nir->info.gs.vertices_out = vertices_out;
187    nir->info.gs.invocations = 1;
188    nir->info.gs.active_stream_mask = 1;
189 
190    while (varyings) {
191       char tmp[100];
192       const int i = u_bit_scan64(&varyings);
193 
194       unsigned frac_slots = key->varyings->slots[i].location_frac_mask;
195       while (frac_slots) {
196          int j = u_bit_scan(&frac_slots);
197          snprintf(tmp, ARRAY_SIZE(tmp), "in_%d", emit_ctx->num_vars);
198          emit_ctx->in[emit_ctx->num_vars] = nir_variable_create(nir,
199                                                                 nir_var_shader_in,
200                                                                 glsl_array_type(key->varyings->slots[i].types[j], 3, 0),
201                                                                 tmp);
202          emit_ctx->in[emit_ctx->num_vars]->data.location = i;
203          emit_ctx->in[emit_ctx->num_vars]->data.location_frac = j;
204          emit_ctx->in[emit_ctx->num_vars]->data.driver_location = key->varyings->slots[i].vars[j].driver_location;
205          emit_ctx->in[emit_ctx->num_vars]->data.interpolation = key->varyings->slots[i].vars[j].interpolation;
206          emit_ctx->in[emit_ctx->num_vars]->data.compact = key->varyings->slots[i].vars[j].compact;
207 
208          /* Don't create an output for the edge flag variable */
209          if (i == VARYING_SLOT_EDGE) {
210             edgeflag_var = emit_ctx->in[emit_ctx->num_vars];
211             continue;
212          } else if (i == VARYING_SLOT_POS) {
213              pos_var = emit_ctx->in[emit_ctx->num_vars];
214          }
215 
216          snprintf(tmp, ARRAY_SIZE(tmp), "out_%d", emit_ctx->num_vars);
217          emit_ctx->out[emit_ctx->num_vars] = nir_variable_create(nir,
218                                                                  nir_var_shader_out,
219                                                                  key->varyings->slots[i].types[j],
220                                                                  tmp);
221          emit_ctx->out[emit_ctx->num_vars]->data.location = i;
222          emit_ctx->out[emit_ctx->num_vars]->data.location_frac = j;
223          emit_ctx->out[emit_ctx->num_vars]->data.driver_location = key->varyings->slots[i].vars[j].driver_location;
224          emit_ctx->out[emit_ctx->num_vars]->data.interpolation = key->varyings->slots[i].vars[j].interpolation;
225          emit_ctx->out[emit_ctx->num_vars]->data.compact = key->varyings->slots[i].vars[j].compact;
226 
227          emit_ctx->num_vars++;
228       }
229    }
230 
231    if (key->has_front_face) {
232       emit_ctx->front_facing_var = nir_variable_create(nir,
233                                                        nir_var_shader_out,
234                                                        glsl_uint_type(),
235                                                        "gl_FrontFacing");
236       emit_ctx->front_facing_var->data.location = VARYING_SLOT_VAR12;
237       emit_ctx->front_facing_var->data.driver_location = emit_ctx->num_vars;
238       emit_ctx->front_facing_var->data.interpolation = INTERP_MODE_FLAT;
239    }
240 
241    /* Temporary variable "loop_index" to loop over input vertices */
242    nir_function_impl *impl = nir_shader_get_entrypoint(nir);
243    nir_variable *loop_index_var =
244       nir_local_variable_create(impl, glsl_uint_type(), "loop_index");
245    emit_ctx->loop_index_deref = nir_build_deref_var(b, loop_index_var);
246    nir_store_deref(b, emit_ctx->loop_index_deref, nir_imm_int(b, 0), 1);
247 
248    nir_def *diagonal_vertex = NULL;
249    if (key->edge_flag_fix) {
250       nir_def *prim_id = nir_load_primitive_id(b);
251       nir_def *odd = nir_build_alu(b, nir_op_imod,
252                                        prim_id,
253                                        nir_imm_int(b, 2),
254                                        NULL, NULL);
255       diagonal_vertex = nir_bcsel(b, nir_i2b(b, odd),
256                                   nir_imm_int(b, 2),
257                                   nir_imm_int(b, 1));
258    }
259 
260    if (key->cull_mode != PIPE_FACE_NONE || key->has_front_face) {
261       if (key->cull_mode == PIPE_FACE_BACK)
262          emit_ctx->edgeflag_cmp = nir_cull_face(b, pos_var, key->front_ccw);
263       else if (key->cull_mode == PIPE_FACE_FRONT)
264          emit_ctx->edgeflag_cmp = nir_cull_face(b, pos_var, !key->front_ccw);
265 
266       if (key->has_front_face) {
267          if (key->cull_mode == PIPE_FACE_BACK)
268             emit_ctx->front_facing = emit_ctx->edgeflag_cmp;
269          else
270             emit_ctx->front_facing = nir_cull_face(b, pos_var, key->front_ccw);
271          emit_ctx->front_facing = nir_i2i32(b, emit_ctx->front_facing);
272       }
273    }
274 
275    /**
276     *  while {
277     *     if (loop_index >= 3)
278     *        break;
279     */
280    emit_ctx->loop = nir_push_loop(b);
281 
282    emit_ctx->loop_index = nir_load_deref(b, emit_ctx->loop_index_deref);
283    nir_def *cmp = nir_ige_imm(b, emit_ctx->loop_index, 3);
284    nir_if *loop_check = nir_push_if(b, cmp);
285    nir_jump(b, nir_jump_break);
286    nir_pop_if(b, loop_check);
287 
288    if (edgeflag_var) {
289       nir_def *edge_flag =
290          nir_load_deref(b, nir_build_deref_array(b, nir_build_deref_var(b, edgeflag_var), emit_ctx->loop_index));
291       nir_def *is_edge = nir_feq_imm(b, nir_channel(b, edge_flag, 0), 1.0);
292       if (emit_ctx->edgeflag_cmp)
293          emit_ctx->edgeflag_cmp = nir_iand(b, emit_ctx->edgeflag_cmp, is_edge);
294       else
295          emit_ctx->edgeflag_cmp = is_edge;
296    }
297 
298    if (key->edge_flag_fix) {
299       nir_def *is_edge = nir_ine(b, emit_ctx->loop_index, diagonal_vertex);
300       if (emit_ctx->edgeflag_cmp)
301          emit_ctx->edgeflag_cmp = nir_iand(b, emit_ctx->edgeflag_cmp, is_edge);
302       else
303          emit_ctx->edgeflag_cmp = is_edge;
304    }
305 
306    return true;
307 }
308 
309 static struct d3d12_shader_selector *
d3d12_finish_emit_primitives_gs(struct emit_primitives_context * emit_ctx,bool end_primitive)310 d3d12_finish_emit_primitives_gs(struct emit_primitives_context *emit_ctx, bool end_primitive)
311 {
312    struct pipe_shader_state templ;
313    nir_builder *b = &emit_ctx->b;
314    nir_shader *nir = b->shader;
315 
316    /**
317     *     loop_index++;
318     *  }
319     */
320    nir_store_deref(b, emit_ctx->loop_index_deref, nir_iadd_imm(b, emit_ctx->loop_index, 1), 1);
321    nir_pop_loop(b, emit_ctx->loop);
322 
323    if (end_primitive)
324       nir_end_primitive(b, 0);
325 
326    nir_validate_shader(nir, "in d3d12_lower_edge_flags");
327 
328    NIR_PASS_V(nir, nir_lower_var_copies);
329 
330    templ.type = PIPE_SHADER_IR_NIR;
331    templ.ir.nir = nir;
332    templ.stream_output.num_outputs = 0;
333 
334    return d3d12_create_shader(emit_ctx->ctx, PIPE_SHADER_GEOMETRY, &templ);
335 }
336 
337 static d3d12_shader_selector*
d3d12_emit_points(struct d3d12_context * ctx,struct d3d12_gs_variant_key * key)338 d3d12_emit_points(struct d3d12_context *ctx, struct d3d12_gs_variant_key *key)
339 {
340    struct emit_primitives_context emit_ctx = {0};
341    nir_builder *b = &emit_ctx.b;
342 
343    d3d12_begin_emit_primitives_gs(&emit_ctx, ctx, key, MESA_PRIM_POINTS, 3);
344 
345    /**
346     *  if (edge_flag)
347     *     out_position = in_position;
348     *  else
349     *     out_position = vec4(-2.0, -2.0, 0.0, 1.0); // Invalid position
350     *
351     *  [...] // Copy other variables
352     *
353     *  EmitVertex();
354     */
355    for (unsigned i = 0; i < emit_ctx.num_vars; ++i) {
356       nir_def *index = (key->flat_varyings & (1ull << emit_ctx.in[i]->data.location))  ?
357                               nir_imm_int(b, (key->flatshade_first ? 0 : 2)) : emit_ctx.loop_index;
358       nir_deref_instr *in_value = nir_build_deref_array(b, nir_build_deref_var(b, emit_ctx.in[i]), index);
359       if (emit_ctx.in[i]->data.location == VARYING_SLOT_POS && emit_ctx.edgeflag_cmp) {
360          nir_if *edge_check = nir_push_if(b, emit_ctx.edgeflag_cmp);
361          copy_vars(b, nir_build_deref_var(b, emit_ctx.out[i]), in_value);
362          nir_if *edge_else = nir_push_else(b, edge_check);
363          nir_store_deref(b, nir_build_deref_var(b, emit_ctx.out[i]),
364                          nir_imm_vec4(b, -2.0, -2.0, 0.0, 1.0), 0xf);
365          nir_pop_if(b, edge_else);
366       } else {
367          copy_vars(b, nir_build_deref_var(b, emit_ctx.out[i]), in_value);
368       }
369    }
370    if (key->has_front_face)
371        nir_store_var(b, emit_ctx.front_facing_var, emit_ctx.front_facing, 0x1);
372    nir_emit_vertex(b, 0);
373 
374    return d3d12_finish_emit_primitives_gs(&emit_ctx, false);
375 }
376 
377 static d3d12_shader_selector*
d3d12_emit_lines(struct d3d12_context * ctx,struct d3d12_gs_variant_key * key)378 d3d12_emit_lines(struct d3d12_context *ctx, struct d3d12_gs_variant_key *key)
379 {
380    struct emit_primitives_context emit_ctx = {0};
381    nir_builder *b = &emit_ctx.b;
382 
383    d3d12_begin_emit_primitives_gs(&emit_ctx, ctx, key, MESA_PRIM_LINE_STRIP, 6);
384 
385    nir_def *next_index = nir_imod_imm(b, nir_iadd_imm(b, emit_ctx.loop_index, 1), 3);
386 
387    /* First vertex */
388    for (unsigned i = 0; i < emit_ctx.num_vars; ++i) {
389       nir_def *index = (key->flat_varyings & (1ull << emit_ctx.in[i]->data.location)) ?
390                               nir_imm_int(b, (key->flatshade_first ? 0 : 2)) : emit_ctx.loop_index;
391       nir_deref_instr *in_value = nir_build_deref_array(b, nir_build_deref_var(b, emit_ctx.in[i]), index);
392       copy_vars(b, nir_build_deref_var(b, emit_ctx.out[i]), in_value);
393    }
394    if (key->has_front_face)
395        nir_store_var(b, emit_ctx.front_facing_var, emit_ctx.front_facing, 0x1);
396    nir_emit_vertex(b, 0);
397 
398    /* Second vertex. If not an edge, use same position as first vertex */
399    for (unsigned i = 0; i < emit_ctx.num_vars; ++i) {
400       nir_def *index = next_index;
401       if (emit_ctx.in[i]->data.location == VARYING_SLOT_POS)
402          index = nir_bcsel(b, emit_ctx.edgeflag_cmp, next_index, emit_ctx.loop_index);
403       else if (key->flat_varyings & (1ull << emit_ctx.in[i]->data.location))
404          index = nir_imm_int(b, 2);
405       copy_vars(b, nir_build_deref_var(b, emit_ctx.out[i]),
406                 nir_build_deref_array(b, nir_build_deref_var(b, emit_ctx.in[i]), index));
407    }
408    if (key->has_front_face)
409        nir_store_var(b, emit_ctx.front_facing_var, emit_ctx.front_facing, 0x1);
410    nir_emit_vertex(b, 0);
411 
412    nir_end_primitive(b, 0);
413 
414    return d3d12_finish_emit_primitives_gs(&emit_ctx, false);
415 }
416 
417 static d3d12_shader_selector*
d3d12_emit_triangles(struct d3d12_context * ctx,struct d3d12_gs_variant_key * key)418 d3d12_emit_triangles(struct d3d12_context *ctx, struct d3d12_gs_variant_key *key)
419 {
420    struct emit_primitives_context emit_ctx = {0};
421    nir_builder *b = &emit_ctx.b;
422 
423    d3d12_begin_emit_primitives_gs(&emit_ctx, ctx, key, MESA_PRIM_TRIANGLE_STRIP, 3);
424 
425    /**
426     *  [...] // Copy variables
427     *
428     *  EmitVertex();
429     */
430 
431    nir_def *incr = NULL;
432 
433    if (key->provoking_vertex > 0)
434       incr = nir_imm_int(b, key->provoking_vertex);
435    else
436       incr = nir_imm_int(b, 3);
437 
438    if (key->alternate_tri) {
439       nir_def *odd = nir_imod_imm(b, nir_load_primitive_id(b), 2);
440       incr = nir_isub(b, incr, odd);
441    }
442 
443    assert(incr != NULL);
444    nir_def *index = nir_imod_imm(b, nir_iadd(b, emit_ctx.loop_index, incr), 3);
445    for (unsigned i = 0; i < emit_ctx.num_vars; ++i) {
446       nir_deref_instr *in_value = nir_build_deref_array(b, nir_build_deref_var(b, emit_ctx.in[i]), index);
447       copy_vars(b, nir_build_deref_var(b, emit_ctx.out[i]), in_value);
448    }
449    nir_emit_vertex(b, 0);
450 
451    return d3d12_finish_emit_primitives_gs(&emit_ctx, true);
452 }
453 
454 static uint32_t
hash_gs_variant_key(const void * key)455 hash_gs_variant_key(const void *key)
456 {
457    d3d12_gs_variant_key *v = (d3d12_gs_variant_key*)key;
458    uint32_t hash = _mesa_hash_data(v, offsetof(d3d12_gs_variant_key, varyings));
459    if (v->varyings)
460       hash = _mesa_hash_data_with_seed(v->varyings->slots, sizeof(v->varyings->slots[0]) * v->varyings->max, hash);
461    return hash;
462 }
463 
464 static bool
equals_gs_variant_key(const void * a,const void * b)465 equals_gs_variant_key(const void *a, const void *b)
466 {
467    return memcmp(a, b, sizeof(d3d12_gs_variant_key)) == 0;
468 }
469 
470 void
d3d12_gs_variant_cache_init(struct d3d12_context * ctx)471 d3d12_gs_variant_cache_init(struct d3d12_context *ctx)
472 {
473    ctx->gs_variant_cache = _mesa_hash_table_create(NULL, NULL, equals_gs_variant_key);
474 }
475 
476 static void
delete_entry(struct hash_entry * entry)477 delete_entry(struct hash_entry *entry)
478 {
479    d3d12_shader_free((d3d12_shader_selector *)entry->data);
480 }
481 
482 void
d3d12_gs_variant_cache_destroy(struct d3d12_context * ctx)483 d3d12_gs_variant_cache_destroy(struct d3d12_context *ctx)
484 {
485    _mesa_hash_table_destroy(ctx->gs_variant_cache, delete_entry);
486 }
487 
488 static struct d3d12_shader_selector *
create_geometry_shader_variant(struct d3d12_context * ctx,struct d3d12_gs_variant_key * key)489 create_geometry_shader_variant(struct d3d12_context *ctx, struct d3d12_gs_variant_key *key)
490 {
491    d3d12_shader_selector *gs = NULL;
492 
493    if (key->passthrough)
494       gs = d3d12_make_passthrough_gs(ctx, key);
495    else if (key->provoking_vertex > 0 || key->alternate_tri)
496       gs = d3d12_emit_triangles(ctx, key);
497    else if (key->fill_mode == PIPE_POLYGON_MODE_POINT)
498       gs = d3d12_emit_points(ctx, key);
499    else if (key->fill_mode == PIPE_POLYGON_MODE_LINE)
500       gs = d3d12_emit_lines(ctx, key);
501 
502    if (gs) {
503       gs->is_variant = true;
504       gs->gs_key = *key;
505    }
506 
507    return gs;
508 }
509 
510 d3d12_shader_selector *
d3d12_get_gs_variant(struct d3d12_context * ctx,struct d3d12_gs_variant_key * key)511 d3d12_get_gs_variant(struct d3d12_context *ctx, struct d3d12_gs_variant_key *key)
512 {
513    uint32_t hash = hash_gs_variant_key(key);
514    struct hash_entry *entry = _mesa_hash_table_search_pre_hashed(ctx->gs_variant_cache,
515                                                                  hash, key);
516    if (!entry) {
517       d3d12_shader_selector *gs = create_geometry_shader_variant(ctx, key);
518       entry = _mesa_hash_table_insert_pre_hashed(ctx->gs_variant_cache,
519                                                  hash, &gs->gs_key, gs);
520       assert(entry);
521    }
522 
523    return (d3d12_shader_selector *)entry->data;
524 }
525