1 /*
2 * Copyright © 2018 Valve Corporation
3 * Copyright © 2018 Google
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 *
24 */
25
26 #include "aco_builder.h"
27 #include "aco_ir.h"
28
29 #include <vector>
30
31 /*
32 * Insert p_linear_start instructions right before RA to correctly allocate
33 * temporaries for reductions that have to disrespect EXEC by executing in
34 * WWM.
35 */
36
37 namespace aco {
38
39 void
setup_reduce_temp(Program * program)40 setup_reduce_temp(Program* program)
41 {
42 unsigned last_top_level_block_idx = 0;
43 unsigned maxSize = 0;
44
45 std::vector<bool> hasReductions(program->blocks.size());
46 for (Block& block : program->blocks) {
47 for (aco_ptr<Instruction>& instr : block.instructions) {
48 if (instr->opcode == aco_opcode::p_interp_gfx11 ||
49 instr->opcode == aco_opcode::p_bpermute_permlane) {
50 maxSize = MAX2(maxSize, 1);
51 hasReductions[block.index] = true;
52 } else if (instr->format == Format::PSEUDO_REDUCTION) {
53 maxSize = MAX2(maxSize, instr->operands[0].size());
54 hasReductions[block.index] = true;
55 }
56 }
57 }
58
59 if (maxSize == 0)
60 return;
61
62 assert(maxSize == 1 || maxSize == 2);
63 Temp reduceTmp(0, RegClass(RegType::vgpr, maxSize).as_linear());
64 Temp vtmp(0, RegClass(RegType::vgpr, maxSize).as_linear());
65 int inserted_at = -1;
66 int vtmp_inserted_at = -1;
67
68 for (Block& block : program->blocks) {
69
70 if (block.kind & block_kind_top_level) {
71 last_top_level_block_idx = block.index;
72
73 /* TODO: this could be improved in this case:
74 * start_linear_vgpr
75 * if (...) {
76 * use_linear_vgpr
77 * }
78 * end_linear_vgpr
79 * Here, the linear vgpr is used before any phi copies, so this isn't necessary.
80 */
81 if (inserted_at >= 0) {
82 aco_ptr<Instruction> end{create_instruction<Instruction>(
83 aco_opcode::p_end_linear_vgpr, Format::PSEUDO, vtmp_inserted_at >= 0 ? 2 : 1, 0)};
84 end->operands[0] = Operand(reduceTmp);
85 if (vtmp_inserted_at >= 0)
86 end->operands[1] = Operand(vtmp);
87 /* insert after the phis of the block */
88 std::vector<aco_ptr<Instruction>>::iterator it = block.instructions.begin();
89 while ((*it)->opcode == aco_opcode::p_linear_phi || (*it)->opcode == aco_opcode::p_phi)
90 ++it;
91 block.instructions.insert(it, std::move(end));
92 inserted_at = vtmp_inserted_at = -1;
93 }
94 }
95
96 if (!hasReductions[block.index])
97 continue;
98
99 std::vector<aco_ptr<Instruction>>::iterator it;
100 for (it = block.instructions.begin(); it != block.instructions.end(); ++it) {
101 Instruction* instr = (*it).get();
102 if (instr->format != Format::PSEUDO_REDUCTION &&
103 instr->opcode != aco_opcode::p_interp_gfx11 &&
104 instr->opcode != aco_opcode::p_bpermute_permlane)
105 continue;
106
107 if ((int)last_top_level_block_idx != inserted_at) {
108 reduceTmp = program->allocateTmp(reduceTmp.regClass());
109 aco_ptr<Pseudo_instruction> create{create_instruction<Pseudo_instruction>(
110 aco_opcode::p_start_linear_vgpr, Format::PSEUDO, 0, 1)};
111 create->definitions[0] = Definition(reduceTmp);
112 /* find the right place to insert this definition */
113 if (last_top_level_block_idx == block.index) {
114 /* insert right before the current instruction */
115 it = block.instructions.insert(it, std::move(create));
116 it++;
117 /* inserted_at is intentionally not updated here, so later blocks
118 * would insert at the end instead of using this one. */
119 } else {
120 assert(last_top_level_block_idx < block.index);
121 /* insert before the branch at last top level block */
122 std::vector<aco_ptr<Instruction>>& instructions =
123 program->blocks[last_top_level_block_idx].instructions;
124 instructions.insert(std::next(instructions.begin(), instructions.size() - 1),
125 std::move(create));
126 inserted_at = last_top_level_block_idx;
127 }
128 }
129
130 /* same as before, except for the vector temporary instead of the reduce temporary */
131 bool need_vtmp = false;
132 if (instr->isReduction()) {
133 ReduceOp op = instr->reduction().reduce_op;
134 unsigned cluster_size = instr->reduction().cluster_size;
135 need_vtmp = op == imul32 || op == fadd64 || op == fmul64 || op == fmin64 ||
136 op == fmax64 || op == umin64 || op == umax64 || op == imin64 ||
137 op == imax64 || op == imul64;
138 bool gfx10_need_vtmp = op == imul8 || op == imax8 || op == imin8 || op == umin8 ||
139 op == imul16 || op == imax16 || op == imin16 || op == umin16 ||
140 op == iadd64;
141
142 if (program->gfx_level >= GFX10 && cluster_size == 64)
143 need_vtmp = true;
144 if (program->gfx_level >= GFX10 && gfx10_need_vtmp)
145 need_vtmp = true;
146 if (program->gfx_level <= GFX7)
147 need_vtmp = true;
148
149 need_vtmp |= cluster_size == 32;
150 }
151
152 if (need_vtmp && (int)last_top_level_block_idx != vtmp_inserted_at) {
153 vtmp = program->allocateTmp(vtmp.regClass());
154 aco_ptr<Pseudo_instruction> create{create_instruction<Pseudo_instruction>(
155 aco_opcode::p_start_linear_vgpr, Format::PSEUDO, 0, 1)};
156 create->definitions[0] = Definition(vtmp);
157 if (last_top_level_block_idx == block.index) {
158 it = block.instructions.insert(it, std::move(create));
159 it++;
160 } else {
161 assert(last_top_level_block_idx < block.index);
162 std::vector<aco_ptr<Instruction>>& instructions =
163 program->blocks[last_top_level_block_idx].instructions;
164 instructions.insert(std::next(instructions.begin(), instructions.size() - 1),
165 std::move(create));
166 vtmp_inserted_at = last_top_level_block_idx;
167 }
168 }
169
170 if (instr->isReduction()) {
171 instr->operands[1] = Operand(reduceTmp);
172 if (need_vtmp)
173 instr->operands[2] = Operand(vtmp);
174 } else {
175 assert(instr->opcode == aco_opcode::p_interp_gfx11 ||
176 instr->opcode == aco_opcode::p_bpermute_permlane);
177 instr->operands[0] = Operand(reduceTmp);
178 instr->operands[0].setLateKill(true);
179 }
180 }
181 }
182 }
183
184 }; // namespace aco
185