xref: /third_party/mesa3d/src/freedreno/ir3/ir3_cse.c (revision bf215546)
1/*
2 * Copyright (C) 2014 Valve 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 FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 * SOFTWARE.
22 */
23
24#include "ir3.h"
25
26#define XXH_INLINE_ALL
27#include "xxhash.h"
28
29/* This pass handles CSE'ing repeated expressions created in the process of
30 * translating from NIR. Currently this is just collect's. Also, currently
31 * this is intra-block only, to make it work over multiple block we'd need to
32 * bring forward dominance calculation.
33 */
34
35#define HASH(hash, data) XXH32(&(data), sizeof(data), hash)
36
37static uint32_t
38hash_instr(const void *data)
39{
40   const struct ir3_instruction *instr = data;
41   uint32_t hash = 0;
42
43   hash = HASH(hash, instr->opc);
44   hash = HASH(hash, instr->dsts[0]->flags);
45   foreach_src (src, (struct ir3_instruction *)instr) {
46      if (src->flags & IR3_REG_CONST) {
47         if (src->flags & IR3_REG_RELATIV)
48            hash = HASH(hash, src->array.offset);
49         else
50            hash = HASH(hash, src->num);
51      } else if (src->flags & IR3_REG_IMMED) {
52         hash = HASH(hash, src->uim_val);
53      } else {
54         if (src->flags & IR3_REG_ARRAY)
55            hash = HASH(hash, src->array.offset);
56         hash = HASH(hash, src->def);
57      }
58   }
59
60   if (opc_cat(instr->opc) == 1) {
61      hash = HASH(hash, instr->cat1.dst_type);
62      hash = HASH(hash, instr->cat1.src_type);
63      hash = HASH(hash, instr->cat1.round);
64   }
65
66   return hash;
67}
68
69static bool
70instrs_equal(const struct ir3_instruction *i1, const struct ir3_instruction *i2)
71{
72   if (i1->opc != i2->opc)
73      return false;
74
75   if (i1->dsts_count != i2->dsts_count)
76      return false;
77
78   if (i1->srcs_count != i2->srcs_count)
79      return false;
80
81   if (i1->dsts[0]->flags != i2->dsts[0]->flags)
82      return false;
83
84   for (unsigned i = 0; i < i1->srcs_count; i++) {
85      const struct ir3_register *i1_reg = i1->srcs[i], *i2_reg = i2->srcs[i];
86
87      if (i1_reg->flags != i2_reg->flags)
88         return false;
89
90      if (i1_reg->flags & IR3_REG_CONST) {
91         if (i1_reg->flags & IR3_REG_RELATIV) {
92            if (i1_reg->array.offset != i2_reg->array.offset)
93               return false;
94         } else {
95            if (i1_reg->num != i2_reg->num)
96               return false;
97         }
98      } else if (i1_reg->flags & IR3_REG_IMMED) {
99         if (i1_reg->uim_val != i2_reg->uim_val)
100            return false;
101      } else {
102         if (i1_reg->flags & IR3_REG_ARRAY) {
103            if (i1_reg->array.offset != i2_reg->array.offset)
104               return false;
105         }
106         if (i1_reg->def != i2_reg->def)
107            return false;
108      }
109   }
110
111   if (opc_cat(i1->opc) == 1) {
112      if (i1->cat1.dst_type != i2->cat1.dst_type ||
113          i1->cat1.src_type != i2->cat1.src_type ||
114          i1->cat1.round != i2->cat1.round)
115         return false;
116   }
117
118   return true;
119}
120
121static bool
122instr_can_cse(const struct ir3_instruction *instr)
123{
124   if (instr->opc != OPC_META_COLLECT && instr->opc != OPC_MOV)
125      return false;
126
127   if (!is_dest_gpr(instr->dsts[0]) || (instr->dsts[0]->flags & IR3_REG_ARRAY))
128      return false;
129
130   return true;
131}
132
133static bool
134cmp_func(const void *data1, const void *data2)
135{
136   return instrs_equal(data1, data2);
137}
138
139bool
140ir3_cse(struct ir3 *ir)
141{
142   struct set *instr_set = _mesa_set_create(NULL, hash_instr, cmp_func);
143   foreach_block (block, &ir->block_list) {
144      _mesa_set_clear(instr_set, NULL);
145
146      foreach_instr (instr, &block->instr_list) {
147         instr->data = NULL;
148
149         if (!instr_can_cse(instr))
150            continue;
151
152         bool found;
153         struct set_entry *entry =
154            _mesa_set_search_or_add(instr_set, instr, &found);
155         if (found)
156            instr->data = (void *)entry->key;
157      }
158   }
159
160   bool progress = false;
161   foreach_block (block, &ir->block_list) {
162      foreach_instr (instr, &block->instr_list) {
163         foreach_src (src, instr) {
164            if ((src->flags & IR3_REG_SSA) && src->def &&
165                src->def->instr->data) {
166               progress = true;
167               struct ir3_instruction *instr = src->def->instr->data;
168               src->def = instr->dsts[0];
169            }
170         }
171      }
172   }
173
174   _mesa_set_destroy(instr_set, NULL);
175   return progress;
176}
177