src/compiler/nir/tests/opt_if_tests.cpp

   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_if_test : public ::testing::Test {
  28 protected:
  29    nir_opt_if_test();
  30    ~nir_opt_if_test();
  31
  32    nir_builder bld;
  33
  34    nir_ssa_def *in_def;
  35    nir_variable *out_var;
  36 };
  37
  38 nir_opt_if_test::nir_opt_if_test()
  39 {
  40    glsl_type_singleton_init_or_ref();
  41
  42    static const nir_shader_compiler_options options = { };
  43    nir_builder_init_simple_shader(&bld, NULL, MESA_SHADER_VERTEX, &options);
  44
  45    nir_variable *var = nir_variable_create(bld.shader, nir_var_shader_in, glsl_int_type(), "in");
  46    in_def = nir_load_var(&bld, var);
  47
  48    out_var = nir_variable_create(bld.shader, nir_var_shader_out, glsl_int_type(), "out");
  49 }
  50
  51 nir_opt_if_test::~nir_opt_if_test()
  52 {
  53    ralloc_free(bld.shader);
  54    glsl_type_singleton_decref();
  55 }
  56
  57 TEST_F(nir_opt_if_test, opt_if_simplification)
  58 {
  59    /* Tests that opt_if_simplification correctly optimizes a simple case:
  60     *
  61     * vec1 1 ssa_2 = ieq ssa_0, ssa_1
  62     * if ssa_2 {
  63     *    block block_2:
  64     * } else {
  65     *    block block_3:
  66     *    do_work()
  67     * }
  68     */
  69
  70    nir_ssa_def *one = nir_imm_int(&bld, 1);
  71
  72    nir_ssa_def *cmp_result = nir_ieq(&bld, in_def, one);
  73    nir_if *nif = nir_push_if(&bld, cmp_result);
  74
  75    nir_push_else(&bld, NULL);
  76
  77    // do_work
  78    nir_store_var(&bld, out_var, one, 1);
  79
  80    nir_pop_if(&bld, NULL);
  81
  82    ASSERT_TRUE(nir_opt_if(bld.shader, false));
  83
  84    nir_validate_shader(bld.shader, NULL);
  85
  86    ASSERT_TRUE(!exec_list_is_empty((&nir_if_first_then_block(nif)->instr_list)));
  87    ASSERT_TRUE(exec_list_is_empty((&nir_if_first_else_block(nif)->instr_list)));
  88 }
  89
  90 TEST_F(nir_opt_if_test, opt_if_simplification_single_source_phi_after_if)
  91 {
  92    /* Tests that opt_if_simplification correctly handles single-source
  93     * phis after the if.
  94     *
  95     * vec1 1 ssa_2 = ieq ssa_0, ssa_1
  96     * if ssa_2 {
  97     *    block block_2:
  98     * } else {
  99     *    block block_3:
 100     *    do_work()
 101     *    return
 102     * }
 103     * block block_4:
 104     * vec1 32 ssa_3 = phi block_2: ssa_0
 105     */
 106
 107    nir_ssa_def *one = nir_imm_int(&bld, 1);
 108
 109    nir_ssa_def *cmp_result = nir_ieq(&bld, in_def, one);
 110    nir_if *nif = nir_push_if(&bld, cmp_result);
 111
 112    nir_push_else(&bld, NULL);
 113
 114    // do_work
 115    nir_store_var(&bld, out_var, one, 1);
 116
 117    nir_jump_instr *jump = nir_jump_instr_create(bld.shader, nir_jump_return);
 118    nir_builder_instr_insert(&bld, &jump->instr);
 119
 120    nir_pop_if(&bld, NULL);
 121
 122    nir_block *then_block = nir_if_last_then_block(nif);
 123
 124    nir_phi_instr *const phi = nir_phi_instr_create(bld.shader);
 125
 126    nir_phi_src *phi_src;
 127    phi_src = ralloc(phi, nir_phi_src);
 128    phi_src->pred = then_block;
 129    phi_src->src = nir_src_for_ssa(one);
 130    exec_list_push_tail(&phi->srcs, &phi_src->node);
 131
 132    nir_ssa_dest_init(&phi->instr, &phi->dest,
 133                      one->num_components, one->bit_size, NULL);
 134
 135    nir_builder_instr_insert(&bld, &phi->instr);
 136
 137    ASSERT_TRUE(nir_opt_if(bld.shader, false));
 138
 139    nir_validate_shader(bld.shader, NULL);
 140
 141    ASSERT_TRUE(nir_block_ends_in_jump(nir_if_last_then_block(nif)));
 142    ASSERT_TRUE(exec_list_is_empty((&nir_if_first_else_block(nif)->instr_list)));
 143 }