1 /*
2  * Copyright © 2018 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 DEALINGS
21  * IN THE SOFTWARE.
22  */
23 
24 #include <gtest/gtest.h>
25 #include "brw_vec4.h"
26 #include "program/program.h"
27 
28 using namespace brw;
29 
30 class dead_code_eliminate_vec4_test : public ::testing::Test {
31    virtual void SetUp();
32    virtual void TearDown();
33 
34 public:
35    struct brw_compiler *compiler;
36    struct intel_device_info *devinfo;
37    void *ctx;
38    struct gl_shader_program *shader_prog;
39    struct brw_vue_prog_data *prog_data;
40    vec4_visitor *v;
41 };
42 
43 class dead_code_eliminate_vec4_visitor : public vec4_visitor
44 {
45 public:
dead_code_eliminate_vec4_visitor(struct brw_compiler * compiler,void * mem_ctx,nir_shader * shader,struct brw_vue_prog_data * prog_data)46    dead_code_eliminate_vec4_visitor(struct brw_compiler *compiler,
47                                  void *mem_ctx,
48                                  nir_shader *shader,
49                                  struct brw_vue_prog_data *prog_data)
50       : vec4_visitor(compiler, NULL, NULL, prog_data, shader, mem_ctx,
51                      false /* no_spills */, false)
52    {
53       prog_data->dispatch_mode = DISPATCH_MODE_4X2_DUAL_OBJECT;
54    }
55 
56 protected:
make_reg_for_system_value(int)57    virtual dst_reg *make_reg_for_system_value(int /* location */)
58    {
59       unreachable("Not reached");
60    }
61 
setup_payload()62    virtual void setup_payload()
63    {
64       unreachable("Not reached");
65    }
66 
emit_prolog()67    virtual void emit_prolog()
68    {
69       unreachable("Not reached");
70    }
71 
emit_thread_end()72    virtual void emit_thread_end()
73    {
74       unreachable("Not reached");
75    }
76 
emit_urb_write_header(int)77    virtual void emit_urb_write_header(int /* mrf */)
78    {
79       unreachable("Not reached");
80    }
81 
emit_urb_write_opcode(bool)82    virtual vec4_instruction *emit_urb_write_opcode(bool /* complete */)
83    {
84       unreachable("Not reached");
85    }
86 };
87 
88 
SetUp()89 void dead_code_eliminate_vec4_test::SetUp()
90 {
91    ctx = ralloc_context(NULL);
92    compiler = rzalloc(ctx, struct brw_compiler);
93    devinfo = rzalloc(ctx, struct intel_device_info);
94    compiler->devinfo = devinfo;
95 
96    prog_data = ralloc(ctx, struct brw_vue_prog_data);
97    nir_shader *shader =
98       nir_shader_create(ctx, MESA_SHADER_VERTEX, NULL, NULL);
99 
100   v = new dead_code_eliminate_vec4_visitor(compiler, ctx, shader, prog_data);
101 
102    devinfo->ver = 4;
103    devinfo->verx10 = devinfo->ver * 10;
104 }
105 
TearDown()106 void dead_code_eliminate_vec4_test::TearDown()
107 {
108    delete v;
109    v = NULL;
110 
111    ralloc_free(ctx);
112    ctx = NULL;
113 }
114 
115 static void
dead_code_eliminate(vec4_visitor * v)116 dead_code_eliminate(vec4_visitor *v)
117 {
118    const bool print = getenv("TEST_DEBUG");
119 
120    if (print) {
121       fprintf(stderr, "instructions before:\n");
122       v->dump_instructions();
123    }
124 
125    v->calculate_cfg();
126    v->dead_code_eliminate();
127 
128    if (print) {
129       fprintf(stderr, "instructions after:\n");
130       v->dump_instructions();
131    }
132 }
133 
TEST_F(dead_code_eliminate_vec4_test,some_dead_channels_all_flags_used)134 TEST_F(dead_code_eliminate_vec4_test, some_dead_channels_all_flags_used)
135 {
136    const vec4_builder bld = vec4_builder(v).at_end();
137    src_reg r1 = src_reg(v, glsl_type::vec4_type);
138    src_reg r2 = src_reg(v, glsl_type::vec4_type);
139    src_reg r3 = src_reg(v, glsl_type::vec4_type);
140    src_reg r4 = src_reg(v, glsl_type::vec4_type);
141    src_reg r5 = src_reg(v, glsl_type::vec4_type);
142    src_reg r6 = src_reg(v, glsl_type::vec4_type);
143 
144    /* Sequence like the following should not be modified by DCE.
145     *
146     *     cmp.l.f0(8)     g4<1>F         g2<4,4,1>.wF   g1<4,4,1>.xF
147     *     mov(8)          g5<1>.xF       g4<4,4,1>.xF
148     *     (+f0.x) sel(8)  g6<1>UD        g3<4>UD        g6<4>UD
149     */
150    vec4_instruction *test_cmp =
151       bld.CMP(dst_reg(r4), r2, r1, BRW_CONDITIONAL_L);
152 
153    test_cmp->src[0].swizzle = BRW_SWIZZLE_WWWW;
154    test_cmp->src[1].swizzle = BRW_SWIZZLE_XXXX;
155 
156    vec4_instruction *test_mov =
157       bld.MOV(dst_reg(r5), r4);
158 
159    test_mov->dst.writemask = WRITEMASK_X;
160    test_mov->src[0].swizzle = BRW_SWIZZLE_XXXX;
161 
162    vec4_instruction *test_sel =
163       bld.SEL(dst_reg(r6), r3, r6);
164 
165    set_predicate(BRW_PREDICATE_NORMAL, test_sel);
166 
167    /* The scratch write is here just to make r5 and r6 be live so that the
168     * whole program doesn't get eliminated by DCE.
169     */
170    v->emit(v->SCRATCH_WRITE(dst_reg(r4), r6, r5));
171 
172    dead_code_eliminate(v);
173 
174    EXPECT_EQ(test_cmp->dst.writemask, WRITEMASK_XYZW);
175 }
176