1 /*
2 * Copyright (C) 2021 Collabora, Ltd.
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 FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 * SOFTWARE.
22 */
23
24 #include "compiler/nir/nir_builder.h"
25 #include "pan_ir.h"
26
27 /* Lower gl_HelperInvocation to (gl_SampleMaskIn == 0), this depends on
28 * architectural details but is required for correct operation with
29 * multisampling. NIR's lowering won't work for us, since there is no in-spec
30 * way to implement load_sample_id_no_per_sample. */
31
32 static bool
pan_lower_helper_invocation_instr(nir_builder * b,nir_intrinsic_instr * intr,void * data)33 pan_lower_helper_invocation_instr(nir_builder *b, nir_intrinsic_instr *intr,
34 void *data)
35 {
36 if (intr->intrinsic != nir_intrinsic_load_helper_invocation)
37 return false;
38
39 b->cursor = nir_before_instr(&intr->instr);
40
41 nir_def *mask = nir_load_sample_mask_in(b);
42 nir_def *eq = nir_ieq_imm(b, mask, 0);
43 nir_def_rewrite_uses(&intr->def, eq);
44
45 return true;
46 }
47
48 bool
pan_lower_helper_invocation(nir_shader * shader)49 pan_lower_helper_invocation(nir_shader *shader)
50 {
51 return nir_shader_intrinsics_pass(
52 shader, pan_lower_helper_invocation_instr,
53 nir_metadata_control_flow, NULL);
54 }
55