1/*
2 * Copyright © 2014 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 * Authors:
24 *    Jason Ekstrand (jason@jlekstrand.net)
25 *
26 */
27
28#ifndef _NIR_SEARCH_
29#define _NIR_SEARCH_
30
31#include "nir.h"
32
33#define NIR_SEARCH_MAX_VARIABLES 16
34
35typedef enum {
36   nir_search_value_expression,
37   nir_search_value_variable,
38   nir_search_value_constant,
39} nir_search_value_type;
40
41typedef struct {
42   nir_search_value_type type;
43
44   unsigned bit_size;
45} nir_search_value;
46
47typedef struct {
48   nir_search_value value;
49
50   /** The variable index;  Must be less than NIR_SEARCH_MAX_VARIABLES */
51   unsigned variable;
52
53   /** Indicates that the given variable must be a constant
54    *
55    * This is only allowed in search expressions and indicates that the
56    * given variable is only allowed to match constant values.
57    */
58   bool is_constant;
59
60   /** Indicates that the given variable must have a certain type
61    *
62    * This is only allowed in search expressions and indicates that the
63    * given variable is only allowed to match values that come from an ALU
64    * instruction with the given output type.  A type of nir_type_void
65    * means it can match any type.
66    *
67    * Note: A variable that is both constant and has a non-void type will
68    * never match anything.
69    */
70   nir_alu_type type;
71
72   /** Optional condition fxn ptr
73    *
74    * This is only allowed in search expressions, and allows additional
75    * constraints to be placed on the match.  Typically used for 'is_constant'
76    * variables to require, for example, power-of-two in order for the search
77    * to match.
78    */
79   bool (*cond)(nir_alu_instr *instr, unsigned src,
80                unsigned num_components, const uint8_t *swizzle);
81} nir_search_variable;
82
83typedef struct {
84   nir_search_value value;
85
86   nir_alu_type type;
87
88   union {
89      uint64_t u;
90      int64_t i;
91      double d;
92   } data;
93} nir_search_constant;
94
95typedef struct {
96   nir_search_value value;
97
98   /* When set on a search expression, the expression will only match an SSA
99    * value that does *not* have the exact bit set.  If unset, the exact bit
100    * on the SSA value is ignored.
101    */
102   bool inexact;
103
104   nir_op opcode;
105   const nir_search_value *srcs[4];
106
107   /** Optional condition fxn ptr
108    *
109    * This allows additional constraints on expression matching, it is
110    * typically used to match an expressions uses such as the number of times
111    * the expression is used, and whether its used by an if.
112    */
113   bool (*cond)(nir_alu_instr *instr);
114} nir_search_expression;
115
116NIR_DEFINE_CAST(nir_search_value_as_variable, nir_search_value,
117                nir_search_variable, value,
118                type, nir_search_value_variable)
119NIR_DEFINE_CAST(nir_search_value_as_constant, nir_search_value,
120                nir_search_constant, value,
121                type, nir_search_value_constant)
122NIR_DEFINE_CAST(nir_search_value_as_expression, nir_search_value,
123                nir_search_expression, value,
124                type, nir_search_value_expression)
125
126nir_alu_instr *
127nir_replace_instr(nir_alu_instr *instr, const nir_search_expression *search,
128                  const nir_search_value *replace, void *mem_ctx);
129
130#endif /* _NIR_SEARCH_ */
131