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
28using namespace brw;
29
30class dead_code_eliminate_test : public ::testing::Test {
31   virtual void SetUp();
32   virtual void TearDown();
33
34public:
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
43class dead_code_eliminate_vec4_visitor : public vec4_visitor
44{
45public:
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 */, -1, false)
52   {
53      prog_data->dispatch_mode = DISPATCH_MODE_4X2_DUAL_OBJECT;
54   }
55
56protected:
57   virtual dst_reg *make_reg_for_system_value(int /* location */)
58   {
59      unreachable("Not reached");
60   }
61
62   virtual void setup_payload()
63   {
64      unreachable("Not reached");
65   }
66
67   virtual void emit_prolog()
68   {
69      unreachable("Not reached");
70   }
71
72   virtual void emit_thread_end()
73   {
74      unreachable("Not reached");
75   }
76
77   virtual void emit_urb_write_header(int /* mrf */)
78   {
79      unreachable("Not reached");
80   }
81
82   virtual vec4_instruction *emit_urb_write_opcode(bool /* complete */)
83   {
84      unreachable("Not reached");
85   }
86};
87
88
89void dead_code_eliminate_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
106void dead_code_eliminate_test::TearDown()
107{
108   delete v;
109   v = NULL;
110
111   ralloc_free(ctx);
112   ctx = NULL;
113}
114
115static void
116dead_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
134TEST_F(dead_code_eliminate_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