1 /* 2 * Copyright © 2020 Google, Inc. 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 #ifndef _DECODE_H_ 25 #define _DECODE_H_ 26 27 #include <isaspec-isa.h> 28 #include <stdbool.h> 29 #include <stdint.h> 30 31 /* 32 * Defines the tables which are generated from xml for disassembly 33 */ 34 35 struct decode_scope; 36 struct isa_bitset; 37 38 /** 39 * Table of enum values 40 */ 41 struct isa_enum { 42 unsigned num_values; 43 struct { 44 unsigned val; 45 const char *display; 46 } values[]; 47 }; 48 49 /** 50 * An expression used to for conditional overrides, derived fields, etc 51 */ 52 typedef uint64_t (*isa_expr_t)(struct decode_scope *scope); 53 54 /** 55 * Used by generated expr functions 56 */ 57 uint64_t isa_decode_field(struct decode_scope *scope, const char *field_name); 58 59 /** 60 * For bitset fields, there are some cases where we want to "remap" field 61 * names, essentially allowing one to parameterize a nested bitset when 62 * it resolves fields in an enclosing bitset. 63 */ 64 struct isa_field_params { 65 unsigned num_params; 66 struct { 67 const char *name; 68 const char *as; 69 } params[]; 70 }; 71 72 /** 73 * Description of a single field within a bitset case. 74 */ 75 struct isa_field { 76 const char *name; 77 isa_expr_t expr; /* for virtual "derived" fields */ 78 unsigned low; 79 unsigned high; 80 enum { 81 /* Basic types: */ 82 TYPE_BRANCH, /* branch target, like INT but optional labeling*/ 83 TYPE_INT, 84 TYPE_UINT, 85 TYPE_HEX, 86 TYPE_OFFSET, /* Like INT but formated with +/- or omitted if ==0 */ 87 TYPE_UOFFSET, /* Like UINT but formated with + or omitted if ==0 */ 88 TYPE_FLOAT, 89 TYPE_BOOL, 90 TYPE_ENUM, 91 92 /* To assert a certain value in a given range of bits.. not 93 * used for pattern matching, but allows an override to specify 94 * that a certain bitpattern in some "unused" bits is expected 95 */ 96 TYPE_ASSERT, 97 98 /* For fields that are decoded with another bitset hierarchy: */ 99 TYPE_BITSET, 100 } type; 101 union { 102 const struct isa_bitset **bitsets; /* if type==BITSET */ 103 bitmask_t val; /* if type==ASSERT */ 104 const struct isa_enum *enums; /* if type==ENUM */ 105 const char *display; /* if type==BOOL */ 106 }; 107 108 /** 109 * type==BITSET fields can also optionally provide remapping for 110 * field names 111 */ 112 const struct isa_field_params *params; 113 }; 114 115 /** 116 * A bitset consists of N "cases", with the last one (with case->expr==NULL) 117 * being the default. 118 * 119 * When resolving a field, display template string, etc, all the cases with 120 * an expression that evaluates to non-zero are consider, falling back to 121 * the last (default) case. 122 */ 123 struct isa_case { 124 isa_expr_t expr; 125 const char *display; 126 unsigned num_fields; 127 struct isa_field fields[]; 128 }; 129 130 /** 131 * An individual bitset, the leaves of a bitset inheritance hiearchy will 132 * have the match and mask to match a single instruction (or arbitrary 133 * bit-pattern) against. 134 */ 135 struct isa_bitset { 136 const struct isa_bitset *parent; 137 const char *name; 138 struct { 139 unsigned min; 140 unsigned max; 141 } gen; 142 bitmask_t match; 143 bitmask_t dontcare; 144 bitmask_t mask; 145 unsigned num_cases; 146 const struct isa_case *cases[]; 147 }; 148 149 #endif /* _DECODE_H_ */ 150