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 "tcg/tcg.h" 27 28 29 /** 30 * DisasJumpType: 31 * @DISAS_NEXT: Next instruction in program order. 32 * @DISAS_TOO_MANY: Too many instructions translated. 33 * @DISAS_NORETURN: Following code is dead. 34 * @DISAS_TARGET_*: Start of target-specific conditions. 35 * 36 * What instruction to disassemble next. 37 */ 38 typedef enum DisasJumpType { 39 DISAS_NEXT, 40 DISAS_TOO_MANY, 41 DISAS_NORETURN, 42 DISAS_TARGET_0, 43 DISAS_TARGET_1, 44 DISAS_TARGET_2, 45 DISAS_TARGET_3, 46 DISAS_TARGET_4, 47 DISAS_TARGET_5, 48 DISAS_TARGET_6, 49 DISAS_TARGET_7, 50 DISAS_TARGET_8, 51 DISAS_TARGET_9, 52 DISAS_TARGET_10, 53 DISAS_TARGET_11, 54 } DisasJumpType; 55 56 /** 57 * DisasContextBase: 58 * @tb: Translation block for this disassembly. 59 * @pc_first: Address of first guest instruction in this TB. 60 * @pc_next: Address of next guest instruction in this TB (current during 61 * disassembly). 62 * @is_jmp: What instruction to disassemble next. 63 * @num_insns: Number of translated instructions (including current). 64 * @max_insns: Maximum number of instructions to be translated in this TB. 65 * @singlestep_enabled: "Hardware" single stepping enabled. 66 * 67 * Architecture-agnostic disassembly context. 68 */ 69 typedef struct DisasContextBase { 70 const TranslationBlock *tb; 71 target_ulong pc_first; 72 target_ulong pc_next; 73 DisasJumpType is_jmp; 74 int num_insns; 75 int max_insns; 76 bool singlestep_enabled; 77 } DisasContextBase; 78 79 /** 80 * TranslatorOps: 81 * @init_disas_context: 82 * Initialize the target-specific portions of DisasContext struct. 83 * The generic DisasContextBase has already been initialized. 84 * 85 * @tb_start: 86 * Emit any code required before the start of the main loop, 87 * after the generic gen_tb_start(). 88 * 89 * @insn_start: 90 * Emit the tcg_gen_insn_start opcode. 91 * 92 * @breakpoint_check: 93 * When called, the breakpoint has already been checked to match the PC, 94 * but the target may decide the breakpoint missed the address 95 * (e.g., due to conditions encoded in their flags). Return true to 96 * indicate that the breakpoint did hit, in which case no more breakpoints 97 * are checked. If the breakpoint did hit, emit any code required to 98 * signal the exception, and set db->is_jmp as necessary to terminate 99 * the main loop. 100 * 101 * @translate_insn: 102 * Disassemble one instruction and set db->pc_next for the start 103 * of the following instruction. Set db->is_jmp as necessary to 104 * terminate the main loop. 105 * 106 * @tb_stop: 107 * Emit any opcodes required to exit the TB, based on db->is_jmp. 108 * 109 * @disas_log: 110 * Print instruction disassembly to log. 111 */ 112 typedef struct TranslatorOps { 113 void (*init_disas_context)(DisasContextBase *db, CPUState *cpu); 114 void (*tb_start)(DisasContextBase *db, CPUState *cpu); 115 void (*insn_start)(DisasContextBase *db, CPUState *cpu); 116 bool (*breakpoint_check)(DisasContextBase *db, CPUState *cpu, 117 const CPUBreakpoint *bp); 118 void (*translate_insn)(DisasContextBase *db, CPUState *cpu); 119 void (*tb_stop)(DisasContextBase *db, CPUState *cpu); 120 void (*disas_log)(const DisasContextBase *db, CPUState *cpu); 121 } TranslatorOps; 122 123 /** 124 * translator_loop: 125 * @ops: Target-specific operations. 126 * @db: Disassembly context. 127 * @cpu: Target vCPU. 128 * @tb: Translation block. 129 * @max_insns: Maximum number of insns to translate. 130 * 131 * Generic translator loop. 132 * 133 * Translation will stop in the following cases (in order): 134 * - When is_jmp set by #TranslatorOps::breakpoint_check. 135 * - set to DISAS_TOO_MANY exits after translating one more insn 136 * - set to any other value than DISAS_NEXT exits immediately. 137 * - When is_jmp set by #TranslatorOps::translate_insn. 138 * - set to any value other than DISAS_NEXT exits immediately. 139 * - When the TCG operation buffer is full. 140 * - When single-stepping is enabled (system-wide or on the current vCPU). 141 * - When too many instructions have been translated. 142 */ 143 void translator_loop(const TranslatorOps *ops, DisasContextBase *db, 144 CPUState *cpu, TranslationBlock *tb, int max_insns); 145 146 void translator_loop_temp_check(DisasContextBase *db); 147 148 /** 149 * translator_use_goto_tb 150 * @db: Disassembly context 151 * @dest: target pc of the goto 152 * 153 * Return true if goto_tb is allowed between the current TB 154 * and the destination PC. 155 */ 156 bool translator_use_goto_tb(DisasContextBase *db, target_ulong dest); 157 158 /* 159 * Translator Load Functions 160 * 161 * These are intended to replace the direct usage of the cpu_ld*_code 162 * functions and are mandatory for front-ends that have been migrated 163 * to the common translator_loop. These functions are only intended 164 * to be called from the translation stage and should not be called 165 * from helper functions. Those functions should be converted to encode 166 * the relevant information at translation time. 167 */ 168 169 #define GEN_TRANSLATOR_LD(fullname, type, load_fn, swap_fn) \ 170 static inline type \ 171 fullname ## _swap(CPUArchState *env, abi_ptr pc, bool do_swap) \ 172 { \ 173 type ret = load_fn(env, pc); \ 174 if (do_swap) { \ 175 ret = swap_fn(ret); \ 176 } \ 177 plugin_insn_append(&ret, sizeof(ret)); \ 178 return ret; \ 179 } \ 180 \ 181 static inline type fullname(CPUArchState *env, abi_ptr pc) \ 182 { \ 183 return fullname ## _swap(env, pc, false); \ 184 } 185 186 GEN_TRANSLATOR_LD(translator_ldub, uint8_t, cpu_ldub_code, /* no swap */) 187 GEN_TRANSLATOR_LD(translator_ldsw, int16_t, cpu_ldsw_code, bswap16) 188 GEN_TRANSLATOR_LD(translator_lduw, uint16_t, cpu_lduw_code, bswap16) 189 GEN_TRANSLATOR_LD(translator_ldl, uint32_t, cpu_ldl_code, bswap32) 190 GEN_TRANSLATOR_LD(translator_ldq, uint64_t, cpu_ldq_code, bswap64) 191 #undef GEN_TRANSLATOR_LD 192 193 #endif /* EXEC__TRANSLATOR_H */ 194