brw_fs.h revision 01e04c3f
1/*
2 * Copyright © 2010 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 DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 *    Eric Anholt <eric@anholt.net>
25 *
26 */
27
28#ifndef BRW_FS_H
29#define BRW_FS_H
30
31#include "brw_shader.h"
32#include "brw_ir_fs.h"
33#include "brw_fs_builder.h"
34#include "compiler/nir/nir.h"
35
36struct bblock_t;
37namespace {
38   struct acp_entry;
39}
40
41namespace brw {
42   class fs_live_variables;
43}
44
45struct brw_gs_compile;
46
47static inline fs_reg
48offset(const fs_reg &reg, const brw::fs_builder &bld, unsigned delta)
49{
50   return offset(reg, bld.dispatch_width(), delta);
51}
52
53#define UBO_START ((1 << 16) - 4)
54
55/**
56 * The fragment shader front-end.
57 *
58 * Translates either GLSL IR or Mesa IR (for ARB_fragment_program) into FS IR.
59 */
60class fs_visitor : public backend_shader
61{
62public:
63   fs_visitor(const struct brw_compiler *compiler, void *log_data,
64              void *mem_ctx,
65              const void *key,
66              struct brw_stage_prog_data *prog_data,
67              struct gl_program *prog,
68              const nir_shader *shader,
69              unsigned dispatch_width,
70              int shader_time_index,
71              const struct brw_vue_map *input_vue_map = NULL);
72   fs_visitor(const struct brw_compiler *compiler, void *log_data,
73              void *mem_ctx,
74              struct brw_gs_compile *gs_compile,
75              struct brw_gs_prog_data *prog_data,
76              const nir_shader *shader,
77              int shader_time_index);
78   void init();
79   ~fs_visitor();
80
81   fs_reg vgrf(const glsl_type *const type);
82   void import_uniforms(fs_visitor *v);
83   void setup_uniform_clipplane_values();
84   void compute_clip_distance();
85
86   void VARYING_PULL_CONSTANT_LOAD(const brw::fs_builder &bld,
87                                   const fs_reg &dst,
88                                   const fs_reg &surf_index,
89                                   const fs_reg &varying_offset,
90                                   uint32_t const_offset);
91   void DEP_RESOLVE_MOV(const brw::fs_builder &bld, int grf);
92
93   bool run_fs(bool allow_spilling, bool do_rep_send);
94   bool run_vs();
95   bool run_tcs_single_patch();
96   bool run_tes();
97   bool run_gs();
98   bool run_cs(unsigned min_dispatch_width);
99   void optimize();
100   void allocate_registers(unsigned min_dispatch_width, bool allow_spilling);
101   void setup_fs_payload_gen4();
102   void setup_fs_payload_gen6();
103   void setup_vs_payload();
104   void setup_gs_payload();
105   void setup_cs_payload();
106   void fixup_3src_null_dest();
107   void assign_curb_setup();
108   void calculate_urb_setup();
109   void assign_urb_setup();
110   void convert_attr_sources_to_hw_regs(fs_inst *inst);
111   void assign_vs_urb_setup();
112   void assign_tcs_single_patch_urb_setup();
113   void assign_tes_urb_setup();
114   void assign_gs_urb_setup();
115   bool assign_regs(bool allow_spilling, bool spill_all);
116   void assign_regs_trivial();
117   void calculate_payload_ranges(int payload_node_count,
118                                 int *payload_last_use_ip);
119   void setup_payload_interference(struct ra_graph *g, int payload_reg_count,
120                                   int first_payload_node);
121   int choose_spill_reg(struct ra_graph *g);
122   void spill_reg(int spill_reg);
123   void split_virtual_grfs();
124   bool compact_virtual_grfs();
125   void assign_constant_locations();
126   bool get_pull_locs(const fs_reg &src, unsigned *out_surf_index,
127                      unsigned *out_pull_index);
128   void lower_constant_loads();
129   void invalidate_live_intervals();
130   void calculate_live_intervals();
131   void calculate_register_pressure();
132   void validate();
133   bool opt_algebraic();
134   bool opt_redundant_discard_jumps();
135   bool opt_cse();
136   bool opt_cse_local(bblock_t *block);
137   bool opt_copy_propagation();
138   bool try_copy_propagate(fs_inst *inst, int arg, acp_entry *entry);
139   bool try_constant_propagate(fs_inst *inst, acp_entry *entry);
140   bool opt_copy_propagation_local(void *mem_ctx, bblock_t *block,
141                                   exec_list *acp);
142   bool opt_drop_redundant_mov_to_flags();
143   bool opt_register_renaming();
144   bool opt_bank_conflicts();
145   unsigned bank_conflict_cycles(const fs_inst *inst) const;
146   bool register_coalesce();
147   bool compute_to_mrf();
148   bool eliminate_find_live_channel();
149   bool dead_code_eliminate();
150   bool remove_duplicate_mrf_writes();
151   bool remove_extra_rounding_modes();
152
153   bool opt_sampler_eot();
154   bool virtual_grf_interferes(int a, int b);
155   void schedule_instructions(instruction_scheduler_mode mode);
156   void insert_gen4_send_dependency_workarounds();
157   void insert_gen4_pre_send_dependency_workarounds(bblock_t *block,
158                                                    fs_inst *inst);
159   void insert_gen4_post_send_dependency_workarounds(bblock_t *block,
160                                                     fs_inst *inst);
161   void vfail(const char *msg, va_list args);
162   void fail(const char *msg, ...);
163   void limit_dispatch_width(unsigned n, const char *msg);
164   void lower_uniform_pull_constant_loads();
165   bool lower_load_payload();
166   bool lower_pack();
167   bool lower_conversions();
168   bool lower_logical_sends();
169   bool lower_integer_multiplication();
170   bool lower_minmax();
171   bool lower_simd_width();
172   bool opt_combine_constants();
173
174   void emit_dummy_fs();
175   void emit_repclear_shader();
176   void emit_fragcoord_interpolation(fs_reg wpos);
177   fs_reg *emit_frontfacing_interpolation();
178   fs_reg *emit_samplepos_setup();
179   fs_reg *emit_sampleid_setup();
180   fs_reg *emit_samplemaskin_setup();
181   void emit_interpolation_setup_gen4();
182   void emit_interpolation_setup_gen6();
183   void compute_sample_position(fs_reg dst, fs_reg int_sample_pos);
184   fs_reg emit_mcs_fetch(const fs_reg &coordinate, unsigned components,
185                         const fs_reg &sampler);
186   void emit_gen6_gather_wa(uint8_t wa, fs_reg dst);
187   fs_reg resolve_source_modifiers(const fs_reg &src);
188   void emit_discard_jump();
189   bool opt_peephole_sel();
190   bool opt_peephole_csel();
191   bool opt_peephole_predicated_break();
192   bool opt_saturate_propagation();
193   bool opt_cmod_propagation();
194   bool opt_zero_samples();
195
196   void emit_nir_code();
197   void nir_setup_outputs();
198   void nir_setup_uniforms();
199   void nir_emit_system_values();
200   void nir_emit_impl(nir_function_impl *impl);
201   void nir_emit_cf_list(exec_list *list);
202   void nir_emit_if(nir_if *if_stmt);
203   void nir_emit_loop(nir_loop *loop);
204   void nir_emit_block(nir_block *block);
205   void nir_emit_instr(nir_instr *instr);
206   void nir_emit_alu(const brw::fs_builder &bld, nir_alu_instr *instr);
207   void nir_emit_load_const(const brw::fs_builder &bld,
208                            nir_load_const_instr *instr);
209   void nir_emit_vs_intrinsic(const brw::fs_builder &bld,
210                              nir_intrinsic_instr *instr);
211   void nir_emit_tcs_intrinsic(const brw::fs_builder &bld,
212                               nir_intrinsic_instr *instr);
213   void nir_emit_gs_intrinsic(const brw::fs_builder &bld,
214                              nir_intrinsic_instr *instr);
215   void nir_emit_fs_intrinsic(const brw::fs_builder &bld,
216                              nir_intrinsic_instr *instr);
217   void nir_emit_cs_intrinsic(const brw::fs_builder &bld,
218                              nir_intrinsic_instr *instr);
219   fs_reg get_nir_image_intrinsic_image(const brw::fs_builder &bld,
220                                        nir_intrinsic_instr *instr);
221   void nir_emit_intrinsic(const brw::fs_builder &bld,
222                           nir_intrinsic_instr *instr);
223   void nir_emit_tes_intrinsic(const brw::fs_builder &bld,
224                               nir_intrinsic_instr *instr);
225   void nir_emit_ssbo_atomic(const brw::fs_builder &bld,
226                             int op, nir_intrinsic_instr *instr);
227   void nir_emit_ssbo_atomic_float(const brw::fs_builder &bld,
228                                   int op, nir_intrinsic_instr *instr);
229   void nir_emit_shared_atomic(const brw::fs_builder &bld,
230                               int op, nir_intrinsic_instr *instr);
231   void nir_emit_shared_atomic_float(const brw::fs_builder &bld,
232                                     int op, nir_intrinsic_instr *instr);
233   void nir_emit_texture(const brw::fs_builder &bld,
234                         nir_tex_instr *instr);
235   void nir_emit_jump(const brw::fs_builder &bld,
236                      nir_jump_instr *instr);
237   fs_reg get_nir_src(const nir_src &src);
238   fs_reg get_nir_src_imm(const nir_src &src);
239   fs_reg get_nir_dest(const nir_dest &dest);
240   fs_reg get_indirect_offset(nir_intrinsic_instr *instr);
241   void emit_percomp(const brw::fs_builder &bld, const fs_inst &inst,
242                     unsigned wr_mask);
243
244   bool optimize_extract_to_float(nir_alu_instr *instr,
245                                  const fs_reg &result);
246   bool optimize_frontfacing_ternary(nir_alu_instr *instr,
247                                     const fs_reg &result);
248
249   void emit_alpha_test();
250   fs_inst *emit_single_fb_write(const brw::fs_builder &bld,
251                                 fs_reg color1, fs_reg color2,
252                                 fs_reg src0_alpha, unsigned components);
253   void emit_fb_writes();
254   fs_inst *emit_non_coherent_fb_read(const brw::fs_builder &bld,
255                                      const fs_reg &dst, unsigned target);
256   void emit_urb_writes(const fs_reg &gs_vertex_count = fs_reg());
257   void set_gs_stream_control_data_bits(const fs_reg &vertex_count,
258                                        unsigned stream_id);
259   void emit_gs_control_data_bits(const fs_reg &vertex_count);
260   void emit_gs_end_primitive(const nir_src &vertex_count_nir_src);
261   void emit_gs_vertex(const nir_src &vertex_count_nir_src,
262                       unsigned stream_id);
263   void emit_gs_thread_end();
264   void emit_gs_input_load(const fs_reg &dst, const nir_src &vertex_src,
265                           unsigned base_offset, const nir_src &offset_src,
266                           unsigned num_components, unsigned first_component);
267   void emit_cs_terminate();
268   fs_reg *emit_cs_work_group_id_setup();
269
270   void emit_barrier();
271
272   void emit_shader_time_begin();
273   void emit_shader_time_end();
274   void SHADER_TIME_ADD(const brw::fs_builder &bld,
275                        int shader_time_subindex,
276                        fs_reg value);
277
278   fs_reg get_timestamp(const brw::fs_builder &bld);
279
280   fs_reg interp_reg(int location, int channel);
281
282   int implied_mrf_writes(fs_inst *inst) const;
283
284   virtual void dump_instructions();
285   virtual void dump_instructions(const char *name);
286   void dump_instruction(backend_instruction *inst);
287   void dump_instruction(backend_instruction *inst, FILE *file);
288
289   const void *const key;
290   const struct brw_sampler_prog_key_data *key_tex;
291
292   struct brw_gs_compile *gs_compile;
293
294   struct brw_stage_prog_data *prog_data;
295   struct gl_program *prog;
296
297   const struct brw_vue_map *input_vue_map;
298
299   int *virtual_grf_start;
300   int *virtual_grf_end;
301   brw::fs_live_variables *live_intervals;
302
303   int *regs_live_at_ip;
304
305   /** Number of uniform variable components visited. */
306   unsigned uniforms;
307
308   /** Byte-offset for the next available spot in the scratch space buffer. */
309   unsigned last_scratch;
310
311   /**
312    * Array mapping UNIFORM register numbers to the pull parameter index,
313    * or -1 if this uniform register isn't being uploaded as a pull constant.
314    */
315   int *pull_constant_loc;
316
317   /**
318    * Array mapping UNIFORM register numbers to the push parameter index,
319    * or -1 if this uniform register isn't being uploaded as a push constant.
320    */
321   int *push_constant_loc;
322
323   fs_reg subgroup_id;
324   fs_reg frag_depth;
325   fs_reg frag_stencil;
326   fs_reg sample_mask;
327   fs_reg outputs[VARYING_SLOT_MAX];
328   fs_reg dual_src_output;
329   int first_non_payload_grf;
330   /** Either BRW_MAX_GRF or GEN7_MRF_HACK_START */
331   unsigned max_grf;
332
333   fs_reg *nir_locals;
334   fs_reg *nir_ssa_values;
335   fs_reg *nir_system_values;
336
337   bool failed;
338   char *fail_msg;
339
340   /** Register numbers for thread payload fields. */
341   struct thread_payload {
342      uint8_t subspan_coord_reg[2];
343      uint8_t source_depth_reg[2];
344      uint8_t source_w_reg[2];
345      uint8_t aa_dest_stencil_reg[2];
346      uint8_t dest_depth_reg[2];
347      uint8_t sample_pos_reg[2];
348      uint8_t sample_mask_in_reg[2];
349      uint8_t barycentric_coord_reg[BRW_BARYCENTRIC_MODE_COUNT][2];
350      uint8_t local_invocation_id_reg[2];
351
352      /** The number of thread payload registers the hardware will supply. */
353      uint8_t num_regs;
354   } payload;
355
356   bool source_depth_to_render_target;
357   bool runtime_check_aads_emit;
358
359   fs_reg pixel_x;
360   fs_reg pixel_y;
361   fs_reg wpos_w;
362   fs_reg pixel_w;
363   fs_reg delta_xy[BRW_BARYCENTRIC_MODE_COUNT];
364   fs_reg shader_start_time;
365   fs_reg userplane[MAX_CLIP_PLANES];
366   fs_reg final_gs_vertex_count;
367   fs_reg control_data_bits;
368   fs_reg invocation_id;
369
370   unsigned grf_used;
371   bool spilled_any_registers;
372
373   const unsigned dispatch_width; /**< 8, 16 or 32 */
374   unsigned max_dispatch_width;
375
376   int shader_time_index;
377
378   unsigned promoted_constants;
379   brw::fs_builder bld;
380};
381
382/**
383 * The fragment shader code generator.
384 *
385 * Translates FS IR to actual i965 assembly code.
386 */
387class fs_generator
388{
389public:
390   fs_generator(const struct brw_compiler *compiler, void *log_data,
391                void *mem_ctx,
392                struct brw_stage_prog_data *prog_data,
393                unsigned promoted_constants,
394                bool runtime_check_aads_emit,
395                gl_shader_stage stage);
396   ~fs_generator();
397
398   void enable_debug(const char *shader_name);
399   int generate_code(const cfg_t *cfg, int dispatch_width);
400   const unsigned *get_assembly();
401
402private:
403   void fire_fb_write(fs_inst *inst,
404                      struct brw_reg payload,
405                      struct brw_reg implied_header,
406                      GLuint nr);
407   void generate_fb_write(fs_inst *inst, struct brw_reg payload);
408   void generate_fb_read(fs_inst *inst, struct brw_reg dst,
409                         struct brw_reg payload);
410   void generate_urb_read(fs_inst *inst, struct brw_reg dst, struct brw_reg payload);
411   void generate_urb_write(fs_inst *inst, struct brw_reg payload);
412   void generate_cs_terminate(fs_inst *inst, struct brw_reg payload);
413   void generate_barrier(fs_inst *inst, struct brw_reg src);
414   bool generate_linterp(fs_inst *inst, struct brw_reg dst,
415			 struct brw_reg *src);
416   void generate_tex(fs_inst *inst, struct brw_reg dst, struct brw_reg src,
417                     struct brw_reg surface_index,
418                     struct brw_reg sampler_index);
419   void generate_get_buffer_size(fs_inst *inst, struct brw_reg dst,
420                                 struct brw_reg src,
421                                 struct brw_reg surf_index);
422   void generate_ddx(const fs_inst *inst,
423                     struct brw_reg dst, struct brw_reg src);
424   void generate_ddy(const fs_inst *inst,
425                     struct brw_reg dst, struct brw_reg src);
426   void generate_scratch_write(fs_inst *inst, struct brw_reg src);
427   void generate_scratch_read(fs_inst *inst, struct brw_reg dst);
428   void generate_scratch_read_gen7(fs_inst *inst, struct brw_reg dst);
429   void generate_uniform_pull_constant_load(fs_inst *inst, struct brw_reg dst,
430                                            struct brw_reg index,
431                                            struct brw_reg offset);
432   void generate_uniform_pull_constant_load_gen7(fs_inst *inst,
433                                                 struct brw_reg dst,
434                                                 struct brw_reg surf_index,
435                                                 struct brw_reg payload);
436   void generate_varying_pull_constant_load_gen4(fs_inst *inst,
437                                                 struct brw_reg dst,
438                                                 struct brw_reg index);
439   void generate_varying_pull_constant_load_gen7(fs_inst *inst,
440                                                 struct brw_reg dst,
441                                                 struct brw_reg index,
442                                                 struct brw_reg offset);
443   void generate_mov_dispatch_to_flags(fs_inst *inst);
444
445   void generate_pixel_interpolator_query(fs_inst *inst,
446                                          struct brw_reg dst,
447                                          struct brw_reg src,
448                                          struct brw_reg msg_data,
449                                          unsigned msg_type);
450
451   void generate_set_sample_id(fs_inst *inst,
452                               struct brw_reg dst,
453                               struct brw_reg src0,
454                               struct brw_reg src1);
455
456   void generate_discard_jump(fs_inst *inst);
457
458   void generate_pack_half_2x16_split(fs_inst *inst,
459                                      struct brw_reg dst,
460                                      struct brw_reg x,
461                                      struct brw_reg y);
462   void generate_unpack_half_2x16_split(fs_inst *inst,
463                                        struct brw_reg dst,
464                                        struct brw_reg src);
465
466   void generate_shader_time_add(fs_inst *inst,
467                                 struct brw_reg payload,
468                                 struct brw_reg offset,
469                                 struct brw_reg value);
470
471   void generate_mov_indirect(fs_inst *inst,
472                              struct brw_reg dst,
473                              struct brw_reg reg,
474                              struct brw_reg indirect_byte_offset);
475
476   void generate_shuffle(fs_inst *inst,
477                         struct brw_reg dst,
478                         struct brw_reg src,
479                         struct brw_reg idx);
480
481   void generate_quad_swizzle(const fs_inst *inst,
482                              struct brw_reg dst, struct brw_reg src,
483                              unsigned swiz);
484
485   bool patch_discard_jumps_to_fb_writes();
486
487   const struct brw_compiler *compiler;
488   void *log_data; /* Passed to compiler->*_log functions */
489
490   const struct gen_device_info *devinfo;
491
492   struct brw_codegen *p;
493   struct brw_stage_prog_data * const prog_data;
494
495   unsigned dispatch_width; /**< 8, 16 or 32 */
496
497   exec_list discard_halt_patches;
498   unsigned promoted_constants;
499   bool runtime_check_aads_emit;
500   bool debug_flag;
501   const char *shader_name;
502   gl_shader_stage stage;
503   void *mem_ctx;
504};
505
506namespace brw {
507   inline fs_reg
508   fetch_payload_reg(const brw::fs_builder &bld, uint8_t regs[2],
509                     brw_reg_type type = BRW_REGISTER_TYPE_F, unsigned n = 1)
510   {
511      if (!regs[0])
512         return fs_reg();
513
514      if (bld.dispatch_width() > 16) {
515         const fs_reg tmp = bld.vgrf(type, n);
516         const brw::fs_builder hbld = bld.exec_all().group(16, 0);
517         const unsigned m = bld.dispatch_width() / hbld.dispatch_width();
518         fs_reg *const components = new fs_reg[n * m];
519
520         for (unsigned c = 0; c < n; c++) {
521            for (unsigned g = 0; g < m; g++) {
522               components[c * m + g] =
523                  offset(retype(brw_vec8_grf(regs[g], 0), type), hbld, c);
524            }
525         }
526
527         hbld.LOAD_PAYLOAD(tmp, components, n * m, 0);
528
529         delete[] components;
530         return tmp;
531
532      } else {
533         return fs_reg(retype(brw_vec8_grf(regs[0], 0), type));
534      }
535   }
536
537   /**
538    * Remove any modifiers from the \p i-th source region of the instruction,
539    * including negate, abs and any implicit type conversion to the execution
540    * type.  Instead any source modifiers will be implemented as a separate
541    * MOV instruction prior to the original instruction.
542    */
543   inline bool
544   lower_src_modifiers(fs_visitor *v, bblock_t *block, fs_inst *inst, unsigned i)
545   {
546      assert(inst->components_read(i) == 1);
547      const fs_builder ibld(v, block, inst);
548      const fs_reg tmp = ibld.vgrf(get_exec_type(inst));
549
550      ibld.MOV(tmp, inst->src[i]);
551      inst->src[i] = tmp;
552
553      return true;
554   }
555}
556
557void shuffle_from_32bit_read(const brw::fs_builder &bld,
558                             const fs_reg &dst,
559                             const fs_reg &src,
560                             uint32_t first_component,
561                             uint32_t components);
562
563fs_reg shuffle_for_32bit_write(const brw::fs_builder &bld,
564                               const fs_reg &src,
565                               uint32_t first_component,
566                               uint32_t components);
567
568fs_reg setup_imm_df(const brw::fs_builder &bld,
569                    double v);
570
571fs_reg setup_imm_b(const brw::fs_builder &bld,
572                   int8_t v);
573
574fs_reg setup_imm_ub(const brw::fs_builder &bld,
575                   uint8_t v);
576
577enum brw_barycentric_mode brw_barycentric_mode(enum glsl_interp_mode mode,
578                                               nir_intrinsic_op op);
579
580#endif /* BRW_FS_H */
581