src/gallium/drivers/lima/ir/pp/node_to_instr.c

   1 /*
   2  * Copyright (c) 2017 Lima Project
   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, sub license,
   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
  12  * next paragraph) shall be included in all copies or substantial portions
  13  * of the 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 NON-INFRINGEMENT. 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 #include "ppir.h"
  26
  27
  28 static bool create_new_instr(ppir_block *block, ppir_node *node)
  29 {
  30    ppir_instr *instr = ppir_instr_create(block);
  31    if (unlikely(!instr))
  32       return false;
  33
  34    if (!ppir_instr_insert_node(instr, node))
  35       return false;
  36
  37    return true;
  38 }
  39
  40 /*
  41  * If a node has a pipeline dest, schedule it in the same instruction as its
  42  * successor.
  43  * Since it has a pipeline dest, it must have only one successor and since we
  44  * schedule nodes backwards, its successor must have already been scheduled.
  45  * Load varyings can't output to a pipeline register but are also potentially
  46  * trivial to insert and save an instruction if they have a single successor.
  47  */
  48 static bool ppir_do_node_to_instr_try_insert(ppir_block *block, ppir_node *node)
  49 {
  50    ppir_dest *dest = ppir_node_get_dest(node);
  51
  52    if (dest && dest->type == ppir_target_pipeline) {
  53       assert(ppir_node_has_single_src_succ(node));
  54       ppir_node *succ = ppir_node_first_succ(node);
  55       assert(succ);
  56       assert(succ->instr);
  57
  58       return ppir_instr_insert_node(succ->instr, node);
  59    }
  60
  61    switch (node->type) {
  62       case ppir_node_type_load:
  63          break;
  64       default:
  65          return false;
  66    }
  67
  68    if (!ppir_node_has_single_src_succ(node))
  69       return false;
  70
  71    ppir_node *succ = ppir_node_first_succ(node);
  72    assert(succ);
  73    assert(succ->instr);
  74
  75    return ppir_instr_insert_node(succ->instr, node);
  76 }
  77
  78 static bool ppir_do_one_node_to_instr(ppir_block *block, ppir_node *node)
  79 {
  80    switch (node->type) {
  81    case ppir_node_type_alu:
  82    {
  83       /* don't create an instr for undef node */
  84       if (node->op == ppir_op_undef)
  85          break;
  86
  87       /* merge pred mul and succ add in the same instr can save a reg
  88        * by using pipeline reg ^vmul/^fmul */
  89       ppir_alu_node *alu = ppir_node_to_alu(node);
  90       if (alu->dest.type == ppir_target_ssa &&
  91           ppir_node_has_single_src_succ(node)) {
  92          ppir_node *succ = ppir_node_first_succ(node);
  93          if (succ->instr_pos == PPIR_INSTR_SLOT_ALU_VEC_ADD) {
  94             node->instr_pos = PPIR_INSTR_SLOT_ALU_VEC_MUL;
  95             ppir_instr_insert_mul_node(succ, node);
  96          }
  97          else if (succ->instr_pos == PPIR_INSTR_SLOT_ALU_SCL_ADD &&
  98                   alu->dest.ssa.num_components == 1) {
  99             node->instr_pos = PPIR_INSTR_SLOT_ALU_SCL_MUL;
 100             ppir_instr_insert_mul_node(succ, node);
 101          }
 102       }
 103
 104       /* can't inserted to any existing instr, create one */
 105       if (!node->instr && !create_new_instr(block, node))
 106          return false;
 107
 108       break;
 109    }
 110    case ppir_node_type_load:
 111    case ppir_node_type_load_texture:
 112    {
 113       if (!create_new_instr(block, node))
 114          return false;
 115
 116       /* load varying output can be a register, it doesn't need a mov */
 117       switch (node->op) {
 118       case ppir_op_load_varying:
 119       case ppir_op_load_coords:
 120       case ppir_op_load_coords_reg:
 121       case ppir_op_load_fragcoord:
 122       case ppir_op_load_pointcoord:
 123       case ppir_op_load_frontface:
 124          return true;
 125       default:
 126          break;
 127       }
 128
 129       /* Load cannot be pipelined, likely slot is already taken. Create a mov */
 130       assert(ppir_node_has_single_src_succ(node));
 131       ppir_dest *dest = ppir_node_get_dest(node);
 132       assert(dest->type == ppir_target_pipeline);
 133       ppir_pipeline pipeline_reg = dest->pipeline;
 134
 135       /* Turn dest back to SSA, so we can update predecessors */
 136       ppir_node *succ = ppir_node_first_succ(node);
 137
 138       /* Single succ can still have multiple references to this node */
 139       for (int i = 0; i < ppir_node_get_src_num(succ); i++) {
 140          ppir_src *src = ppir_node_get_src(succ, i);
 141          if (src && src->node == node) {
 142             /* Can consume uniforms directly */
 143             dest->type = ppir_target_ssa;
 144             dest->ssa.index = -1;
 145             ppir_node_target_assign(src, node);
 146          }
 147       }
 148
 149       ppir_node *move = ppir_node_insert_mov(node);
 150       if (unlikely(!move))
 151          return false;
 152
 153       ppir_src *mov_src = ppir_node_get_src(move, 0);
 154       mov_src->type = dest->type = ppir_target_pipeline;
 155       mov_src->pipeline = dest->pipeline = pipeline_reg;
 156
 157       ppir_debug("node_to_instr create move %d for load %d\n",
 158                  move->index, node->index);
 159
 160       if (!ppir_instr_insert_node(node->instr, move))
 161          return false;
 162
 163       break;
 164    }
 165    case ppir_node_type_const: {
 166       /* Const cannot be pipelined, too many consts in the instruction.
 167        * Create a mov. */
 168
 169       ppir_node *move = ppir_node_insert_mov(node);
 170       if (!create_new_instr(block, move))
 171          return false;
 172
 173       ppir_debug("node_to_instr create move %d for const %d\n",
 174                  move->index, node->index);
 175
 176       ppir_dest *dest = ppir_node_get_dest(node);
 177       ppir_src *mov_src = ppir_node_get_src(move, 0);
 178
 179       /* update succ from ^const to ssa mov output */
 180       ppir_dest *move_dest = ppir_node_get_dest(move);
 181       move_dest->type = ppir_target_ssa;
 182       ppir_node *succ = ppir_node_first_succ(move);
 183       ppir_node_replace_child(succ, node, move);
 184
 185       mov_src->type = dest->type = ppir_target_pipeline;
 186       mov_src->pipeline = dest->pipeline = ppir_pipeline_reg_const0;
 187
 188       if (!ppir_instr_insert_node(move->instr, node))
 189          return false;
 190
 191       break;
 192    }
 193    case ppir_node_type_store:
 194    {
 195       if (node->op == ppir_op_store_temp) {
 196          if (!create_new_instr(block, node))
 197             return false;
 198          break;
 199       }
 200    }
 201    case ppir_node_type_discard:
 202       if (!create_new_instr(block, node))
 203          return false;
 204       node->instr->is_end = true;
 205       break;
 206    case ppir_node_type_branch:
 207       if (!create_new_instr(block, node))
 208          return false;
 209       break;
 210    default:
 211       return false;
 212    }
 213
 214    return true;
 215 }
 216
 217 static bool ppir_do_node_to_instr(ppir_block *block, ppir_node *node)
 218 {
 219    /* first try pipeline sched, if that didn't succeed try normal scheduling */
 220    if (!ppir_do_node_to_instr_try_insert(block, node))
 221       if (!ppir_do_one_node_to_instr(block, node))
 222          return false;
 223
 224    if (node->is_end)
 225       node->instr->is_end = true;
 226
 227    /* we have to make sure the dep not be destroyed (due to
 228     * succ change) in ppir_do_node_to_instr, otherwise we can't
 229     * do recursion like this */
 230    ppir_node_foreach_pred(node, dep) {
 231       ppir_node *pred = dep->pred;
 232       bool ready = true;
 233
 234       /* pred may already be processed by the previous pred
 235        * (this pred may be both node and previous pred's child) */
 236       if (pred->instr)
 237          continue;
 238
 239       /* insert pred only when all its successors have been inserted */
 240       ppir_node_foreach_succ(pred, dep) {
 241          ppir_node *succ = dep->succ;
 242          if (!succ->instr) {
 243             ready = false;
 244             break;
 245          }
 246       }
 247
 248       if (ready) {
 249          if (!ppir_do_node_to_instr(block, pred))
 250             return false;
 251       }
 252    }
 253
 254    return true;
 255 }
 256
 257 static bool ppir_create_instr_from_node(ppir_compiler *comp)
 258 {
 259    list_for_each_entry(ppir_block, block, &comp->block_list, list) {
 260       list_for_each_entry(ppir_node, node, &block->node_list, list) {
 261          if (ppir_node_is_root(node)) {
 262             if (!ppir_do_node_to_instr(block, node))
 263                return false;
 264          }
 265       }
 266    }
 267
 268    return true;
 269 }
 270
 271 static void ppir_build_instr_dependency(ppir_compiler *comp)
 272 {
 273    list_for_each_entry(ppir_block, block, &comp->block_list, list) {
 274       list_for_each_entry(ppir_instr, instr, &block->instr_list, list) {
 275          for (int i = 0; i < PPIR_INSTR_SLOT_NUM; i++) {
 276             ppir_node *node = instr->slots[i];
 277             if (node) {
 278                ppir_node_foreach_pred(node, dep) {
 279                   ppir_node *pred = dep->pred;
 280                   if (pred->instr && pred->instr != instr)
 281                      ppir_instr_add_dep(instr, pred->instr);
 282                }
 283             }
 284          }
 285       }
 286    }
 287 }
 288
 289 bool ppir_node_to_instr(ppir_compiler *comp)
 290 {
 291    if (!ppir_create_instr_from_node(comp))
 292       return false;
 293    ppir_instr_print_list(comp);
 294
 295    ppir_build_instr_dependency(comp);
 296    ppir_instr_print_dep(comp);
 297
 298    return true;
 299 }