src/intel/compiler/brw_vec4_tes.cpp

   1 /*
   2  * Copyright © 2013 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /**
  25  * \file brw_vec4_tes.cpp
  26  *
  27  * Tessellaton evaluation shader specific code derived from the vec4_visitor class.
  28  */
  29
  30 #include "brw_vec4_tes.h"
  31 #include "brw_cfg.h"
  32 #include "common/gen_debug.h"
  33
  34 namespace brw {
  35
  36 vec4_tes_visitor::vec4_tes_visitor(const struct brw_compiler *compiler,
  37                                   void *log_data,
  38                                   const struct brw_tes_prog_key *key,
  39                                   struct brw_tes_prog_data *prog_data,
  40                                   const nir_shader *shader,
  41                                   void *mem_ctx,
  42                                   int shader_time_index)
  43    : vec4_visitor(compiler, log_data, &key->tex, &prog_data->base,
  44                   shader, mem_ctx, false, shader_time_index)
  45 {
  46 }
  47
  48 void
  49 vec4_tes_visitor::setup_payload()
  50 {
  51    int reg = 0;
  52
  53    /* The payload always contains important data in r0 and r1, which contains
  54     * the URB handles that are passed on to the URB write at the end
  55     * of the thread.
  56     */
  57    reg += 2;
  58
  59    reg = setup_uniforms(reg);
  60
  61    foreach_block_and_inst(block, vec4_instruction, inst, cfg) {
  62       for (int i = 0; i < 3; i++) {
  63          if (inst->src[i].file != ATTR)
  64             continue;
  65
  66          bool is_64bit = type_sz(inst->src[i].type) == 8;
  67
  68          unsigned slot = inst->src[i].nr + inst->src[i].offset / 16;
  69          struct brw_reg grf = brw_vec4_grf(reg + slot / 2, 4 * (slot % 2));
  70          grf = stride(grf, 0, is_64bit ? 2 : 4, 1);
  71          grf.swizzle = inst->src[i].swizzle;
  72          grf.type = inst->src[i].type;
  73          grf.abs = inst->src[i].abs;
  74          grf.negate = inst->src[i].negate;
  75
  76          /* For 64-bit attributes we can end up with components XY in the
  77           * second half of a register and components ZW in the first half
  78           * of the next. Fix it up here.
  79           */
  80          if (is_64bit && grf.subnr > 0) {
  81             /* We can't do swizzles that mix XY and ZW channels in this case.
  82              * Such cases should have been handled by the scalarization pass.
  83              */
  84             assert((brw_mask_for_swizzle(grf.swizzle) & 0x3) ^
  85                    (brw_mask_for_swizzle(grf.swizzle) & 0xc));
  86             if (brw_mask_for_swizzle(grf.swizzle) & 0xc) {
  87                grf.subnr = 0;
  88                grf.nr++;
  89                grf.swizzle -= BRW_SWIZZLE_ZZZZ;
  90             }
  91          }
  92
  93          inst->src[i] = grf;
  94       }
  95    }
  96
  97    reg += 8 * prog_data->urb_read_length;
  98
  99    this->first_non_payload_grf = reg;
 100 }
 101
 102
 103 void
 104 vec4_tes_visitor::emit_prolog()
 105 {
 106    input_read_header = src_reg(this, glsl_type::uvec4_type);
 107    emit(TES_OPCODE_CREATE_INPUT_READ_HEADER, dst_reg(input_read_header));
 108
 109    this->current_annotation = NULL;
 110 }
 111
 112
 113 void
 114 vec4_tes_visitor::emit_urb_write_header(int mrf)
 115 {
 116    /* No need to do anything for DS; an implied write to this MRF will be
 117     * performed by VS_OPCODE_URB_WRITE.
 118     */
 119    (void) mrf;
 120 }
 121
 122
 123 vec4_instruction *
 124 vec4_tes_visitor::emit_urb_write_opcode(bool complete)
 125 {
 126    /* For DS, the URB writes end the thread. */
 127    if (complete) {
 128       if (INTEL_DEBUG & DEBUG_SHADER_TIME)
 129          emit_shader_time_end();
 130    }
 131
 132    vec4_instruction *inst = emit(VS_OPCODE_URB_WRITE);
 133    inst->urb_write_flags = complete ?
 134       BRW_URB_WRITE_EOT_COMPLETE : BRW_URB_WRITE_NO_FLAGS;
 135
 136    return inst;
 137 }
 138
 139 void
 140 vec4_tes_visitor::nir_emit_intrinsic(nir_intrinsic_instr *instr)
 141 {
 142    const struct brw_tes_prog_data *tes_prog_data =
 143       (const struct brw_tes_prog_data *) prog_data;
 144
 145    switch (instr->intrinsic) {
 146    case nir_intrinsic_load_tess_coord:
 147       /* gl_TessCoord is part of the payload in g1 channels 0-2 and 4-6. */
 148       emit(MOV(get_nir_dest(instr->dest, BRW_REGISTER_TYPE_F),
 149                src_reg(brw_vec8_grf(1, 0))));
 150       break;
 151    case nir_intrinsic_load_tess_level_outer:
 152       if (tes_prog_data->domain == BRW_TESS_DOMAIN_ISOLINE) {
 153          emit(MOV(get_nir_dest(instr->dest, BRW_REGISTER_TYPE_F),
 154                   swizzle(src_reg(ATTR, 1, glsl_type::vec4_type),
 155                           BRW_SWIZZLE_ZWZW)));
 156       } else {
 157          emit(MOV(get_nir_dest(instr->dest, BRW_REGISTER_TYPE_F),
 158                   swizzle(src_reg(ATTR, 1, glsl_type::vec4_type),
 159                           BRW_SWIZZLE_WZYX)));
 160       }
 161       break;
 162    case nir_intrinsic_load_tess_level_inner:
 163       if (tes_prog_data->domain == BRW_TESS_DOMAIN_QUAD) {
 164          emit(MOV(get_nir_dest(instr->dest, BRW_REGISTER_TYPE_F),
 165                   swizzle(src_reg(ATTR, 0, glsl_type::vec4_type),
 166                           BRW_SWIZZLE_WZYX)));
 167       } else {
 168          emit(MOV(get_nir_dest(instr->dest, BRW_REGISTER_TYPE_F),
 169                   src_reg(ATTR, 1, glsl_type::float_type)));
 170       }
 171       break;
 172    case nir_intrinsic_load_primitive_id:
 173       emit(TES_OPCODE_GET_PRIMITIVE_ID,
 174            get_nir_dest(instr->dest, BRW_REGISTER_TYPE_UD));
 175       break;
 176
 177    case nir_intrinsic_load_input:
 178    case nir_intrinsic_load_per_vertex_input: {
 179       src_reg indirect_offset = get_indirect_offset(instr);
 180       unsigned imm_offset = instr->const_index[0];
 181       src_reg header = input_read_header;
 182       bool is_64bit = nir_dest_bit_size(instr->dest) == 64;
 183       unsigned first_component = nir_intrinsic_component(instr);
 184       if (is_64bit)
 185          first_component /= 2;
 186
 187       if (indirect_offset.file != BAD_FILE) {
 188          header = src_reg(this, glsl_type::uvec4_type);
 189          emit(TES_OPCODE_ADD_INDIRECT_URB_OFFSET, dst_reg(header),
 190               input_read_header, indirect_offset);
 191       } else {
 192          /* Arbitrarily only push up to 24 vec4 slots worth of data,
 193           * which is 12 registers (since each holds 2 vec4 slots).
 194           */
 195          const unsigned max_push_slots = 24;
 196          if (imm_offset < max_push_slots) {
 197             const glsl_type *src_glsl_type =
 198                is_64bit ? glsl_type::dvec4_type : glsl_type::ivec4_type;
 199             src_reg src = src_reg(ATTR, imm_offset, src_glsl_type);
 200             src.swizzle = BRW_SWZ_COMP_INPUT(first_component);
 201
 202             const brw_reg_type dst_reg_type =
 203                is_64bit ? BRW_REGISTER_TYPE_DF : BRW_REGISTER_TYPE_D;
 204             emit(MOV(get_nir_dest(instr->dest, dst_reg_type), src));
 205
 206             prog_data->urb_read_length =
 207                MAX2(prog_data->urb_read_length,
 208                     DIV_ROUND_UP(imm_offset + (is_64bit ? 2 : 1), 2));
 209             break;
 210          }
 211       }
 212
 213       if (!is_64bit) {
 214          dst_reg temp(this, glsl_type::ivec4_type);
 215          vec4_instruction *read =
 216             emit(VEC4_OPCODE_URB_READ, temp, src_reg(header));
 217          read->offset = imm_offset;
 218          read->urb_write_flags = BRW_URB_WRITE_PER_SLOT_OFFSET;
 219
 220          src_reg src = src_reg(temp);
 221          src.swizzle = BRW_SWZ_COMP_INPUT(first_component);
 222
 223          /* Copy to target.  We might end up with some funky writemasks landing
 224           * in here, but we really don't want them in the above pseudo-ops.
 225           */
 226          dst_reg dst = get_nir_dest(instr->dest, BRW_REGISTER_TYPE_D);
 227          dst.writemask = brw_writemask_for_size(instr->num_components);
 228          emit(MOV(dst, src));
 229       } else {
 230          /* For 64-bit we need to load twice as many 32-bit components, and for
 231           * dvec3/4 we need to emit 2 URB Read messages
 232           */
 233          dst_reg temp(this, glsl_type::dvec4_type);
 234          dst_reg temp_d = retype(temp, BRW_REGISTER_TYPE_D);
 235
 236          vec4_instruction *read =
 237             emit(VEC4_OPCODE_URB_READ, temp_d, src_reg(header));
 238          read->offset = imm_offset;
 239          read->urb_write_flags = BRW_URB_WRITE_PER_SLOT_OFFSET;
 240
 241          if (instr->num_components > 2) {
 242             read = emit(VEC4_OPCODE_URB_READ, byte_offset(temp_d, REG_SIZE),
 243                         src_reg(header));
 244             read->offset = imm_offset + 1;
 245             read->urb_write_flags = BRW_URB_WRITE_PER_SLOT_OFFSET;
 246          }
 247
 248          src_reg temp_as_src = src_reg(temp);
 249          temp_as_src.swizzle = BRW_SWZ_COMP_INPUT(first_component);
 250
 251          dst_reg shuffled(this, glsl_type::dvec4_type);
 252          shuffle_64bit_data(shuffled, temp_as_src, false);
 253
 254          dst_reg dst = get_nir_dest(instr->dest, BRW_REGISTER_TYPE_DF);
 255          dst.writemask = brw_writemask_for_size(instr->num_components);
 256          emit(MOV(dst, src_reg(shuffled)));
 257       }
 258       break;
 259    }
 260    default:
 261       vec4_visitor::nir_emit_intrinsic(instr);
 262    }
 263 }
 264
 265
 266 void
 267 vec4_tes_visitor::emit_thread_end()
 268 {
 269    /* For DS, we always end the thread by emitting a single vertex.
 270     * emit_urb_write_opcode() will take care of setting the eot flag on the
 271     * SEND instruction.
 272     */
 273    emit_vertex();
 274 }
 275
 276 } /* namespace brw */