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 22 #include "qemu/bswap.h" 23 #include "exec/exec-all.h" 24 #include "exec/cpu_ldst.h" 25 #include "exec/plugin-gen.h" 26 #include "exec/translate-all.h" 27 #include "tcg/tcg.h" 28 29 30 /** 31 * DisasJumpType: 32 * @DISAS_NEXT: Next instruction in program order. 33 * @DISAS_TOO_MANY: Too many instructions translated. 34 * @DISAS_NORETURN: Following code is dead. 35 * @DISAS_TARGET_*: Start of target-specific conditions. 36 * 37 * What instruction to disassemble next. 38 */ 39 typedef enum DisasJumpType { 40 DISAS_NEXT, 41 DISAS_TOO_MANY, 42 DISAS_NORETURN, 43 DISAS_TARGET_0, 44 DISAS_TARGET_1, 45 DISAS_TARGET_2, 46 DISAS_TARGET_3, 47 DISAS_TARGET_4, 48 DISAS_TARGET_5, 49 DISAS_TARGET_6, 50 DISAS_TARGET_7, 51 DISAS_TARGET_8, 52 DISAS_TARGET_9, 53 DISAS_TARGET_10, 54 DISAS_TARGET_11, 55 } DisasJumpType; 56 57 /** 58 * DisasContextBase: 59 * @tb: Translation block for this disassembly. 60 * @pc_first: Address of first guest instruction in this TB. 61 * @pc_next: Address of next guest instruction in this TB (current during 62 * disassembly). 63 * @is_jmp: What instruction to disassemble next. 64 * @num_insns: Number of translated instructions (including current). 65 * @max_insns: Maximum number of instructions to be translated in this TB. 66 * @singlestep_enabled: "Hardware" single stepping enabled. 67 * 68 * Architecture-agnostic disassembly context. 69 */ 70 typedef struct DisasContextBase { 71 const TranslationBlock *tb; 72 target_ulong pc_first; 73 target_ulong pc_next; 74 DisasJumpType is_jmp; 75 int num_insns; 76 int max_insns; 77 bool singlestep_enabled; 78 #ifdef CONFIG_USER_ONLY 79 /* 80 * Guest address of the last byte of the last protected page. 81 * 82 * Pages containing the translated instructions are made non-writable in 83 * order to achieve consistency in case another thread is modifying the 84 * code while translate_insn() fetches the instruction bytes piecemeal. 85 * Such writer threads are blocked on mmap_lock() in page_unprotect(). 86 */ 87 target_ulong page_protect_end; 88 #endif 89 } DisasContextBase; 90 91 /** 92 * TranslatorOps: 93 * @init_disas_context: 94 * Initialize the target-specific portions of DisasContext struct. 95 * The generic DisasContextBase has already been initialized. 96 * 97 * @tb_start: 98 * Emit any code required before the start of the main loop, 99 * after the generic gen_tb_start(). 100 * 101 * @insn_start: 102 * Emit the tcg_gen_insn_start opcode. 103 * 104 * @translate_insn: 105 * Disassemble one instruction and set db->pc_next for the start 106 * of the following instruction. Set db->is_jmp as necessary to 107 * terminate the main loop. 108 * 109 * @tb_stop: 110 * Emit any opcodes required to exit the TB, based on db->is_jmp. 111 * 112 * @disas_log: 113 * Print instruction disassembly to log. 114 */ 115 typedef struct TranslatorOps { 116 void (*init_disas_context)(DisasContextBase *db, CPUState *cpu); 117 void (*tb_start)(DisasContextBase *db, CPUState *cpu); 118 void (*insn_start)(DisasContextBase *db, CPUState *cpu); 119 void (*translate_insn)(DisasContextBase *db, CPUState *cpu); 120 void (*tb_stop)(DisasContextBase *db, CPUState *cpu); 121 void (*disas_log)(const DisasContextBase *db, CPUState *cpu); 122 } TranslatorOps; 123 124 /** 125 * translator_loop: 126 * @ops: Target-specific operations. 127 * @db: Disassembly context. 128 * @cpu: Target vCPU. 129 * @tb: Translation block. 130 * @max_insns: Maximum number of insns to translate. 131 * 132 * Generic translator loop. 133 * 134 * Translation will stop in the following cases (in order): 135 * - When is_jmp set by #TranslatorOps::breakpoint_check. 136 * - set to DISAS_TOO_MANY exits after translating one more insn 137 * - set to any other value than DISAS_NEXT exits immediately. 138 * - When is_jmp set by #TranslatorOps::translate_insn. 139 * - set to any value other than DISAS_NEXT exits immediately. 140 * - When the TCG operation buffer is full. 141 * - When single-stepping is enabled (system-wide or on the current vCPU). 142 * - When too many instructions have been translated. 143 */ 144 void translator_loop(const TranslatorOps *ops, DisasContextBase *db, 145 CPUState *cpu, TranslationBlock *tb, int max_insns); 146 147 void translator_loop_temp_check(DisasContextBase *db); 148 149 /** 150 * translator_use_goto_tb 151 * @db: Disassembly context 152 * @dest: target pc of the goto 153 * 154 * Return true if goto_tb is allowed between the current TB 155 * and the destination PC. 156 */ 157 bool translator_use_goto_tb(DisasContextBase *db, target_ulong dest); 158 159 /* 160 * Translator Load Functions 161 * 162 * These are intended to replace the direct usage of the cpu_ld*_code 163 * functions and are mandatory for front-ends that have been migrated 164 * to the common translator_loop. These functions are only intended 165 * to be called from the translation stage and should not be called 166 * from helper functions. Those functions should be converted to encode 167 * the relevant information at translation time. 168 */ 169 170 #define GEN_TRANSLATOR_LD(fullname, type, load_fn, swap_fn) \ 171 type fullname ## _swap(CPUArchState *env, DisasContextBase *dcbase, \ 172 abi_ptr pc, bool do_swap); \ 173 static inline type fullname(CPUArchState *env, \ 174 DisasContextBase *dcbase, abi_ptr pc) \ 175 { \ 176 return fullname ## _swap(env, dcbase, pc, false); \ 177 } 178 179 #define FOR_EACH_TRANSLATOR_LD(F) \ 180 F(translator_ldub, uint8_t, cpu_ldub_code, /* no swap */) \ 181 F(translator_ldsw, int16_t, cpu_ldsw_code, bswap16) \ 182 F(translator_lduw, uint16_t, cpu_lduw_code, bswap16) \ 183 F(translator_ldl, uint32_t, cpu_ldl_code, bswap32) \ 184 F(translator_ldq, uint64_t, cpu_ldq_code, bswap64) 185 186 FOR_EACH_TRANSLATOR_LD(GEN_TRANSLATOR_LD) 187 188 #undef GEN_TRANSLATOR_LD 189 190 #endif /* EXEC__TRANSLATOR_H */ 191