src/gallium/drivers/r600/sb/sb_gvn.cpp

   1 /*
   2  * Copyright 2013 Vadim Girlin <vadimgirlin@gmail.com>
   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  * on the rights to use, copy, modify, merge, publish, distribute, sub
   8  * license, and/or sell copies of the Software, and to permit persons to whom
   9  * the 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 NON-INFRINGEMENT. IN NO EVENT SHALL
  18  * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
  19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  21  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *      Vadim Girlin
  25  */
  26
  27 #define GVN_DEBUG 0
  28
  29 #if GVN_DEBUG
  30 #define GVN_DUMP(q) do { q } while (0)
  31 #else
  32 #define GVN_DUMP(q)
  33 #endif
  34
  35 #include "sb_shader.h"
  36 #include "sb_pass.h"
  37 #include "sb_sched.h"
  38
  39 namespace r600_sb {
  40
  41 bool gvn::visit(node& n, bool enter) {
  42         if (enter) {
  43
  44
  45                 bool rewrite = true;
  46
  47                 if (n.dst[0]->is_agpr()) {
  48                         rewrite = false;
  49                 }
  50
  51
  52                 process_op(n, rewrite);
  53
  54                 assert(n.parent);
  55
  56                 if (n.parent->subtype == NST_LOOP_PHI_CONTAINER) {
  57                         // There is a problem - sometimes with nested loops
  58                         // loop counter initialization for inner loop is incorrectly hoisted
  59                         // out of the outer loop
  60
  61                         // FIXME not sure if this is enough to fix a problem completely,
  62                         // possibly more complete fix is needed (anyway, the
  63                         // problem was seen only in relatively complex
  64                         // case involving nested loops and
  65                         // indirect access to loop counters (without proper array info
  66                         // loop counters may be considered as array elements too),
  67                         // was not seen in any tests
  68                         // or real apps when proper array information is available in TGSI).
  69
  70                         // For now just mark the instructions that initialize loop counters
  71                         // with DONT_HOIST flag to prevent the insts like MOV r, 0
  72                         // (initialization of inner loop's counter with const)
  73                         // from being hoisted out of the outer loop
  74
  75                         assert(!n.src.empty());
  76                         value *v = n.src[0];
  77
  78                         if (v->is_any_gpr() && v->def)
  79                                 v->def->flags |= NF_DONT_HOIST;
  80                 }
  81
  82         } else {
  83         }
  84         return true;
  85 }
  86
  87 bool gvn::visit(cf_node& n, bool enter) {
  88         if (enter) {
  89                 process_op(n);
  90         } else {
  91         }
  92         return true;
  93 }
  94
  95 bool gvn::visit(alu_node& n, bool enter) {
  96         if (enter) {
  97                 process_op(n);
  98         } else {
  99         }
 100         return true;
 101 }
 102
 103 bool gvn::visit(alu_packed_node& n, bool enter) {
 104         if (enter) {
 105                 process_op(n);
 106         } else {
 107         }
 108         return false;
 109 }
 110
 111 bool gvn::visit(fetch_node& n, bool enter) {
 112         if (enter) {
 113                 process_op(n);
 114         } else {
 115         }
 116         return true;
 117 }
 118
 119 bool gvn::visit(region_node& n, bool enter) {
 120         if (enter) {
 121 // FIXME: loop_phi sources are undefined yet (except theone from the preceding
 122 // code), can we handle that somehow?
 123 //              if (n.loop_phi)
 124 //                      run_on(*n.loop_phi);
 125         } else {
 126                 if (n.loop_phi)
 127                         run_on(*n.loop_phi);
 128
 129                 if (n.phi)
 130                         run_on(*n.phi);
 131         }
 132         return true;
 133 }
 134
 135 bool gvn::process_src(value* &v, bool rewrite) {
 136         if (!v->gvn_source)
 137                 sh.vt.add_value(v);
 138
 139         if (rewrite && !v->gvn_source->is_rel()) {
 140                 v = v->gvn_source;
 141                 return true;
 142         }
 143         return false;
 144 }
 145
 146 // FIXME: maybe handle it in the scheduler?
 147 void gvn::process_alu_src_constants(node &n, value* &v) {
 148         if (n.src.size() < 3) {
 149                 process_src(v, true);
 150                 return;
 151         }
 152
 153         if (!v->gvn_source)
 154                 sh.vt.add_value(v);
 155
 156         rp_kcache_tracker kc(sh);
 157
 158         if (v->gvn_source->is_kcache())
 159                 kc.try_reserve(v->gvn_source->select);
 160
 161         // don't propagate 3rd constant to the trans-only instruction
 162         if (!n.is_alu_packed()) {
 163                 alu_node *a = static_cast<alu_node*>(&n);
 164                 if (a->bc.op_ptr->src_count == 3 && !(a->bc.slot_flags & AF_V)) {
 165                         unsigned const_count = 0;
 166                         for (vvec::iterator I = n.src.begin(), E = n.src.end(); I != E;
 167                                         ++I) {
 168                                 value *c = (*I);
 169                                 if (c && c->is_readonly() && ++const_count == 2) {
 170                                         process_src(v, false);
 171                                         return;
 172                                 }
 173                         }
 174                 }
 175         }
 176
 177         for (vvec::iterator I = n.src.begin(), E = n.src.end(); I != E; ++I) {
 178                 value *c = (*I);
 179
 180                 if (c->is_kcache() && !kc.try_reserve(c->select)) {
 181                         process_src(v, false);
 182                         return;
 183                 }
 184         }
 185         process_src(v, true);
 186 }
 187
 188 void gvn::process_op(node& n, bool rewrite) {
 189
 190         for(vvec::iterator I = n.src.begin(), E = n.src.end(); I != E; ++I) {
 191                 value* &v = *I;
 192                 if (v) {
 193                         if (v->rel) {
 194                                 process_src(v->rel, rewrite);
 195                         }
 196
 197                         if (rewrite && v->gvn_source && v->gvn_source->is_readonly() &&
 198                                         n.is_any_alu()) {
 199                                 process_alu_src_constants(n, v);
 200                         } else if (rewrite && v->gvn_source && v->gvn_source->is_const() &&
 201                                         (n.is_fetch_op(FETCH_OP_VFETCH) ||
 202                                                         n.is_fetch_op(FETCH_OP_SEMFETCH)))
 203                                 process_src(v, false);
 204                         else
 205                                 process_src(v, rewrite);
 206                 }
 207         }
 208         if (n.pred)
 209                 process_src(n.pred, false);
 210
 211         if (n.type == NT_IF) {
 212                 if_node &i = (if_node&)n;
 213                 if (i.cond)
 214                         process_src(i.cond, false);
 215         }
 216
 217         for(vvec::iterator I = n.dst.begin(), E = n.dst.end(); I != E; ++I) {
 218                 value *v = *I;
 219                 if (v) {
 220                         if (v->rel)
 221                                 process_src(v->rel, rewrite);
 222                         sh.vt.add_value(v);
 223                 }
 224         }
 225 }
 226
 227 } // namespace r600_sb