1 /* 2 * Generic intermediate code generation. 3 * 4 * Copyright (C) 2016-2017 Lluís Vilanova <vilanova@ac.upc.edu> 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 */ 9 10 #ifndef EXEC__TRANSLATOR_H 11 #define EXEC__TRANSLATOR_H 12 13 /* 14 * Include this header from a target-specific file, and add a 15 * 16 * DisasContextBase base; 17 * 18 * member in your target-specific DisasContext. 19 */ 20 21 #include "exec/memop.h" 22 #include "exec/vaddr.h" 23 24 /** 25 * DisasJumpType: 26 * @DISAS_NEXT: Next instruction in program order. 27 * @DISAS_TOO_MANY: Too many instructions translated. 28 * @DISAS_NORETURN: Following code is dead. 29 * @DISAS_TARGET_*: Start of target-specific conditions. 30 * 31 * What instruction to disassemble next. 32 */ 33 typedef enum DisasJumpType { 34 DISAS_NEXT, 35 DISAS_TOO_MANY, 36 DISAS_NORETURN, 37 DISAS_TARGET_0, 38 DISAS_TARGET_1, 39 DISAS_TARGET_2, 40 DISAS_TARGET_3, 41 DISAS_TARGET_4, 42 DISAS_TARGET_5, 43 DISAS_TARGET_6, 44 DISAS_TARGET_7, 45 DISAS_TARGET_8, 46 DISAS_TARGET_9, 47 DISAS_TARGET_10, 48 DISAS_TARGET_11, 49 } DisasJumpType; 50 51 /** 52 * DisasContextBase: 53 * @tb: Translation block for this disassembly. 54 * @pc_first: Address of first guest instruction in this TB. 55 * @pc_next: Address of next guest instruction in this TB (current during 56 * disassembly). 57 * @is_jmp: What instruction to disassemble next. 58 * @num_insns: Number of translated instructions (including current). 59 * @max_insns: Maximum number of instructions to be translated in this TB. 60 * @plugin_enabled: TCG plugin enabled in this TB. 61 * @fake_insn: True if translator_fake_ldb used. 62 * @insn_start: The last op emitted by the insn_start hook, 63 * which is expected to be INDEX_op_insn_start. 64 * 65 * Architecture-agnostic disassembly context. 66 */ 67 struct DisasContextBase { 68 TranslationBlock *tb; 69 vaddr pc_first; 70 vaddr pc_next; 71 DisasJumpType is_jmp; 72 int num_insns; 73 int max_insns; 74 bool plugin_enabled; 75 bool fake_insn; 76 uint8_t code_mmuidx; 77 struct TCGOp *insn_start; 78 void *host_addr[2]; 79 80 /* 81 * Record insn data that we cannot read directly from host memory. 82 * There are only two reasons we cannot use host memory: 83 * (1) We are executing from I/O, 84 * (2) We are executing a synthetic instruction (s390x EX). 85 * In both cases we need record exactly one instruction, 86 * and thus the maximum amount of data we record is limited. 87 */ 88 int record_start; 89 int record_len; 90 uint8_t record[32]; 91 }; 92 93 /** 94 * TranslatorOps: 95 * @init_disas_context: 96 * Initialize the target-specific portions of DisasContext struct. 97 * The generic DisasContextBase has already been initialized. 98 * 99 * @tb_start: 100 * Emit any code required before the start of the main loop, 101 * after the generic gen_tb_start(). 102 * 103 * @insn_start: 104 * Emit the tcg_gen_insn_start opcode. 105 * 106 * @translate_insn: 107 * Disassemble one instruction and set db->pc_next for the start 108 * of the following instruction. Set db->is_jmp as necessary to 109 * terminate the main loop. 110 * 111 * @tb_stop: 112 * Emit any opcodes required to exit the TB, based on db->is_jmp. 113 * 114 * @disas_log: 115 * Print instruction disassembly to log. 116 */ 117 typedef struct TranslatorOps { 118 void (*init_disas_context)(DisasContextBase *db, CPUState *cpu); 119 void (*tb_start)(DisasContextBase *db, CPUState *cpu); 120 void (*insn_start)(DisasContextBase *db, CPUState *cpu); 121 void (*translate_insn)(DisasContextBase *db, CPUState *cpu); 122 void (*tb_stop)(DisasContextBase *db, CPUState *cpu); 123 bool (*disas_log)(const DisasContextBase *db, CPUState *cpu, FILE *f); 124 } TranslatorOps; 125 126 /** 127 * translator_loop: 128 * @cpu: Target vCPU. 129 * @tb: Translation block. 130 * @max_insns: Maximum number of insns to translate. 131 * @pc: guest virtual program counter address 132 * @host_pc: host physical program counter address 133 * @ops: Target-specific operations. 134 * @db: Disassembly context. 135 * 136 * Generic translator loop. 137 * 138 * Translation will stop in the following cases (in order): 139 * - When is_jmp set by #TranslatorOps::breakpoint_check. 140 * - set to DISAS_TOO_MANY exits after translating one more insn 141 * - set to any other value than DISAS_NEXT exits immediately. 142 * - When is_jmp set by #TranslatorOps::translate_insn. 143 * - set to any value other than DISAS_NEXT exits immediately. 144 * - When the TCG operation buffer is full. 145 * - When single-stepping is enabled (system-wide or on the current vCPU). 146 * - When too many instructions have been translated. 147 */ 148 void translator_loop(CPUState *cpu, TranslationBlock *tb, int *max_insns, 149 vaddr pc, void *host_pc, const TranslatorOps *ops, 150 DisasContextBase *db); 151 152 /** 153 * translator_use_goto_tb 154 * @db: Disassembly context 155 * @dest: target pc of the goto 156 * 157 * Return true if goto_tb is allowed between the current TB 158 * and the destination PC. 159 */ 160 bool translator_use_goto_tb(DisasContextBase *db, vaddr dest); 161 162 /** 163 * translator_io_start 164 * @db: Disassembly context 165 * 166 * If icount is enabled, set cpu->can_do_io, adjust db->is_jmp to 167 * DISAS_TOO_MANY if it is still DISAS_NEXT, and return true. 168 * Otherwise return false. 169 */ 170 bool translator_io_start(DisasContextBase *db); 171 172 /* 173 * Translator Load Functions 174 * 175 * These are intended to replace the direct usage of the cpu_ld*_code 176 * functions and are mandatory for front-ends that have been migrated 177 * to the common translator_loop. These functions are only intended 178 * to be called from the translation stage and should not be called 179 * from helper functions. Those functions should be converted to encode 180 * the relevant information at translation time. 181 */ 182 183 uint8_t translator_ldub(CPUArchState *env, DisasContextBase *db, vaddr pc); 184 uint16_t translator_lduw_end(CPUArchState *env, DisasContextBase *db, 185 vaddr pc, MemOp endian); 186 uint32_t translator_ldl_end(CPUArchState *env, DisasContextBase *db, 187 vaddr pc, MemOp endian); 188 uint64_t translator_ldq_end(CPUArchState *env, DisasContextBase *db, 189 vaddr pc, MemOp endian); 190 191 #ifdef COMPILING_PER_TARGET 192 static inline uint16_t 193 translator_lduw(CPUArchState *env, DisasContextBase *db, vaddr pc) 194 { 195 return translator_lduw_end(env, db, pc, MO_TE); 196 } 197 198 static inline uint32_t 199 translator_ldl(CPUArchState *env, DisasContextBase *db, vaddr pc) 200 { 201 return translator_ldl_end(env, db, pc, MO_TE); 202 } 203 204 static inline uint64_t 205 translator_ldq(CPUArchState *env, DisasContextBase *db, vaddr pc) 206 { 207 return translator_ldq_end(env, db, pc, MO_TE); 208 } 209 210 static inline uint16_t 211 translator_lduw_swap(CPUArchState *env, DisasContextBase *db, 212 vaddr pc, bool do_swap) 213 { 214 return translator_lduw_end(env, db, pc, MO_TE ^ (do_swap * MO_BSWAP)); 215 } 216 217 static inline uint32_t 218 translator_ldl_swap(CPUArchState *env, DisasContextBase *db, 219 vaddr pc, bool do_swap) 220 { 221 return translator_ldl_end(env, db, pc, MO_TE ^ (do_swap * MO_BSWAP)); 222 } 223 224 static inline uint64_t 225 translator_ldq_swap(CPUArchState *env, DisasContextBase *db, 226 vaddr pc, bool do_swap) 227 { 228 return translator_ldq_end(env, db, pc, MO_TE ^ (do_swap * MO_BSWAP)); 229 } 230 #endif /* COMPILING_PER_TARGET */ 231 232 /** 233 * translator_fake_ld - fake instruction load 234 * @db: Disassembly context 235 * @data: bytes of instruction 236 * @len: number of bytes 237 * 238 * This is a special case helper used where the instruction we are 239 * about to translate comes from somewhere else (e.g. being 240 * re-synthesised for s390x "ex"). It ensures we update other areas of 241 * the translator with details of the executed instruction. 242 */ 243 void translator_fake_ld(DisasContextBase *db, const void *data, size_t len); 244 245 /** 246 * translator_st 247 * @db: disassembly context 248 * @dest: address to copy into 249 * @addr: virtual address within TB 250 * @len: length 251 * 252 * Copy @len bytes from @addr into @dest. 253 * All bytes must have been read during translation. 254 * Return true on success or false on failure. 255 */ 256 bool translator_st(const DisasContextBase *db, void *dest, 257 vaddr addr, size_t len); 258 259 /** 260 * translator_st_len 261 * @db: disassembly context 262 * 263 * Return the number of bytes available to copy from the 264 * current translation block with translator_st. 265 */ 266 size_t translator_st_len(const DisasContextBase *db); 267 268 /** 269 * translator_is_same_page 270 * @db: disassembly context 271 * @addr: virtual address within TB 272 * 273 * Return whether @addr is on the same page as where disassembly started. 274 * Translators can use this to enforce the rule that only single-insn 275 * translation blocks are allowed to cross page boundaries. 276 */ 277 bool translator_is_same_page(const DisasContextBase *db, vaddr addr); 278 279 #endif /* EXEC__TRANSLATOR_H */ 280