1 /*
2 * Copyright © 2020 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 #include <gtest/gtest.h>
24 #include "nir.h"
25 #include "nir_builder.h"
26
27 class nir_opt_lower_returns_test : public ::testing::Test {
28 protected:
29 nir_opt_lower_returns_test();
30 ~nir_opt_lower_returns_test();
31
32 nir_builder bld;
33
34 nir_ssa_def *in_def;
35 };
36
nir_opt_lower_returns_test()37 nir_opt_lower_returns_test::nir_opt_lower_returns_test()
38 {
39 glsl_type_singleton_init_or_ref();
40
41 static const nir_shader_compiler_options options = { };
42 bld = nir_builder_init_simple_shader(MESA_SHADER_VERTEX, &options, "lower returns test");
43
44 nir_variable *var = nir_variable_create(bld.shader, nir_var_shader_in, glsl_int_type(), "in");
45 in_def = nir_load_var(&bld, var);
46 }
47
~nir_opt_lower_returns_test()48 nir_opt_lower_returns_test::~nir_opt_lower_returns_test()
49 {
50 ralloc_free(bld.shader);
51 glsl_type_singleton_decref();
52 }
53
create_one_source_phi(nir_shader * shader,nir_block * pred,nir_ssa_def * def)54 nir_phi_instr *create_one_source_phi(nir_shader *shader, nir_block *pred,
55 nir_ssa_def *def)
56 {
57 nir_phi_instr *phi = nir_phi_instr_create(shader);
58
59 nir_phi_instr_add_src(phi, pred, nir_src_for_ssa(def));
60
61 nir_ssa_dest_init(&phi->instr, &phi->dest,
62 def->num_components, def->bit_size, NULL);
63
64 return phi;
65 }
66
TEST_F(nir_opt_lower_returns_test,phis_after_loop)67 TEST_F(nir_opt_lower_returns_test, phis_after_loop)
68 {
69 /* Test that after lowering of "return" the phis in block_5
70 * have two sources, because block_2 will have block_5
71 * as a successor.
72 *
73 * block block_0:
74 * loop {
75 * block block_1:
76 * if ssa_2 {
77 * block block_2:
78 * return
79 * // succs: block_6
80 * } else {
81 * block block_3:
82 * break;
83 * // succs: block_5
84 * }
85 * block block_4:
86 * }
87 * block block_5:
88 * // preds: block_3
89 * vec1 32 ssa_4 = phi block_3: ssa_1
90 * vec1 32 ssa_5 = phi block_3: ssa_1
91 * // succs: block_6
92 * block block_6:
93 */
94
95 nir_loop *loop = nir_push_loop(&bld);
96
97 nir_ssa_def *one = nir_imm_int(&bld, 1);
98
99 nir_ssa_def *cmp_result = nir_ieq(&bld, in_def, one);
100 nir_if *nif = nir_push_if(&bld, cmp_result);
101
102 nir_jump(&bld, nir_jump_return);
103
104 nir_push_else(&bld, NULL);
105
106 nir_jump(&bld, nir_jump_break);
107
108 nir_pop_if(&bld, NULL);
109
110 nir_block *else_block = nir_if_last_else_block(nif);
111
112 nir_pop_loop(&bld, loop);
113
114 bld.cursor = nir_after_cf_node_and_phis(&loop->cf_node);
115
116 nir_phi_instr *const phi_1 =
117 create_one_source_phi(bld.shader, else_block, one);
118 nir_builder_instr_insert(&bld, &phi_1->instr);
119
120 nir_phi_instr *const phi_2 =
121 create_one_source_phi(bld.shader, else_block, one);
122 nir_builder_instr_insert(&bld, &phi_2->instr);
123
124 ASSERT_TRUE(nir_lower_returns(bld.shader));
125 EXPECT_EQ(phi_1->srcs.length(), 2);
126 EXPECT_EQ(phi_2->srcs.length(), 2);
127
128 nir_validate_shader(bld.shader, NULL);
129 }
130
TEST_F(nir_opt_lower_returns_test,phis_after_outer_loop)131 TEST_F(nir_opt_lower_returns_test, phis_after_outer_loop)
132 {
133 /* Test that after lowering of "return" the phis in block_7
134 * have two sources, because block_6 will have a conditional break
135 * inserted, which will add a new predcessor to block_7.
136 *
137 * block block_0:
138 * loop {
139 * block block_1:
140 * loop {
141 * block block_2:
142 * if ssa_2 {
143 * block block_3:
144 * return
145 * // succs: block_8
146 * } else {
147 * block block_4:
148 * break;
149 * // succs: block_6
150 * }
151 * block block_5:
152 * }
153 * block block_6:
154 * break;
155 * // succs: block_7
156 * }
157 * block block_7:
158 * // preds: block_6
159 * vec1 32 ssa_4 = phi block_6: ssa_1
160 * vec1 32 ssa_5 = phi block_6: ssa_1
161 * // succs: block_8
162 * block block_8:
163 */
164
165 nir_loop *loop_outer = nir_push_loop(&bld);
166
167 bld.cursor = nir_after_cf_list(&loop_outer->body);
168
169 nir_loop *loop_inner = nir_push_loop(&bld);
170
171 bld.cursor = nir_after_cf_list(&loop_inner->body);
172
173 nir_ssa_def *one = nir_imm_int(&bld, 1);
174
175 nir_ssa_def *cmp_result = nir_ieq(&bld, in_def, one);
176 nir_push_if(&bld, cmp_result);
177
178 nir_jump(&bld, nir_jump_return);
179
180 nir_push_else(&bld, NULL);
181
182 nir_jump(&bld, nir_jump_break);
183
184 nir_pop_if(&bld, NULL);
185
186 nir_pop_loop(&bld, loop_inner);
187
188 bld.cursor = nir_after_cf_node_and_phis(&loop_inner->cf_node);
189
190 nir_jump(&bld, nir_jump_break);
191
192 nir_pop_loop(&bld, loop_outer);
193
194 bld.cursor = nir_after_cf_node_and_phis(&loop_outer->cf_node);
195
196 nir_phi_instr *const phi_1 =
197 create_one_source_phi(bld.shader, nir_loop_last_block(loop_outer), one);
198 nir_builder_instr_insert(&bld, &phi_1->instr);
199
200 nir_phi_instr *const phi_2 =
201 create_one_source_phi(bld.shader, nir_loop_last_block(loop_outer), one);
202 nir_builder_instr_insert(&bld, &phi_2->instr);
203
204 ASSERT_TRUE(nir_lower_returns(bld.shader));
205 EXPECT_EQ(phi_1->srcs.length(), 2);
206 EXPECT_EQ(phi_2->srcs.length(), 2);
207
208 nir_validate_shader(bld.shader, NULL);
209 }
210