src/compiler/nir/nir_search.h

   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
  35 typedef enum {
  36    nir_search_value_expression,
  37    nir_search_value_variable,
  38    nir_search_value_constant,
  39 } nir_search_value_type;
  40
  41 typedef struct {
  42    nir_search_value_type type;
  43
  44    unsigned bit_size;
  45 } nir_search_value;
  46
  47 typedef 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
  83 typedef 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
  95 typedef 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
 116 NIR_DEFINE_CAST(nir_search_value_as_variable, nir_search_value,
 117                 nir_search_variable, value,
 118                 type, nir_search_value_variable)
 119 NIR_DEFINE_CAST(nir_search_value_as_constant, nir_search_value,
 120                 nir_search_constant, value,
 121                 type, nir_search_value_constant)
 122 NIR_DEFINE_CAST(nir_search_value_as_expression, nir_search_value,
 123                 nir_search_expression, value,
 124                 type, nir_search_value_expression)
 125
 126 nir_alu_instr *
 127 nir_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_ */