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      1 /*
      2  *  Host code generation
      3  *
      4  *  Copyright (c) 2003 Fabrice Bellard
      5  *
      6  * This library is free software; you can redistribute it and/or
      7  * modify it under the terms of the GNU Lesser General Public
      8  * License as published by the Free Software Foundation; either
      9  * version 2 of the License, or (at your option) any later version.
     10  *
     11  * This library is distributed in the hope that it will be useful,
     12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14  * Lesser General Public License for more details.
     15  *
     16  * You should have received a copy of the GNU Lesser General Public
     17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
     18  */
     19 #include <stdarg.h>
     20 #include <stdlib.h>
     21 #include <stdio.h>
     22 #include <string.h>
     23 #include <inttypes.h>
     24 
     25 #include "config.h"
     26 
     27 #define NO_CPU_IO_DEFS
     28 #include "cpu.h"
     29 #include "exec-all.h"
     30 #include "disas.h"
     31 #include "tcg.h"
     32 #include "qemu-timer.h"
     33 
     34 /* code generation context */
     35 TCGContext tcg_ctx;
     36 
     37 uint16_t gen_opc_buf[OPC_BUF_SIZE];
     38 TCGArg gen_opparam_buf[OPPARAM_BUF_SIZE];
     39 
     40 target_ulong gen_opc_pc[OPC_BUF_SIZE];
     41 uint16_t gen_opc_icount[OPC_BUF_SIZE];
     42 uint8_t gen_opc_instr_start[OPC_BUF_SIZE];
     43 #if defined(TARGET_I386)
     44 uint8_t gen_opc_cc_op[OPC_BUF_SIZE];
     45 #elif defined(TARGET_SPARC)
     46 target_ulong gen_opc_npc[OPC_BUF_SIZE];
     47 target_ulong gen_opc_jump_pc[2];
     48 #elif defined(TARGET_MIPS) || defined(TARGET_SH4)
     49 uint32_t gen_opc_hflags[OPC_BUF_SIZE];
     50 #endif
     51 
     52 #ifdef CONFIG_MEMCHECK
     53 /*
     54  * Memchecker code in this module copies TB PC <-> Guest PC map to the TB
     55  * descriptor after guest code has been translated in cpu_gen_init routine.
     56  */
     57 #include "memcheck/memcheck_api.h"
     58 
     59 /* Array of (tb_pc, guest_pc) pairs, big enough for all translations. This
     60  * array is used to obtain guest PC address from a translated PC address.
     61  * tcg_gen_code_common will fill it up when memchecker is enabled. */
     62 static void* gen_opc_tpc2gpc[OPC_BUF_SIZE * 2];
     63 void** gen_opc_tpc2gpc_ptr = &gen_opc_tpc2gpc[0];
     64 /* Number of (tb_pc, guest_pc) pairs stored in gen_opc_tpc2gpc array. */
     65 unsigned int gen_opc_tpc2gpc_pairs;
     66 #endif  // CONFIG_MEMCHECK
     67 
     68 /* XXX: suppress that */
     69 unsigned long code_gen_max_block_size(void)
     70 {
     71     static unsigned long max;
     72 
     73     if (max == 0) {
     74         max = TCG_MAX_OP_SIZE;
     75 #define DEF(name, iarg, oarg, carg, flags) DEF2((iarg) + (oarg) + (carg))
     76 #define DEF2(copy_size) max = (copy_size > max) ? copy_size : max;
     77 #include "tcg-opc.h"
     78 #undef DEF
     79 #undef DEF2
     80         max *= OPC_MAX_SIZE;
     81     }
     82 
     83     return max;
     84 }
     85 
     86 void cpu_gen_init(void)
     87 {
     88     tcg_context_init(&tcg_ctx);
     89     tcg_set_frame(&tcg_ctx, TCG_AREG0, offsetof(CPUState, temp_buf),
     90                   CPU_TEMP_BUF_NLONGS * sizeof(long));
     91 }
     92 
     93 /* return non zero if the very first instruction is invalid so that
     94    the virtual CPU can trigger an exception.
     95 
     96    '*gen_code_size_ptr' contains the size of the generated code (host
     97    code).
     98 */
     99 int cpu_gen_code(CPUState *env, TranslationBlock *tb, int *gen_code_size_ptr)
    100 {
    101     TCGContext *s = &tcg_ctx;
    102     uint8_t *gen_code_buf;
    103     int gen_code_size;
    104 #ifdef CONFIG_PROFILER
    105     int64_t ti;
    106 #endif
    107 
    108 #ifdef CONFIG_PROFILER
    109     s->tb_count1++; /* includes aborted translations because of
    110                        exceptions */
    111     ti = profile_getclock();
    112 #endif
    113     tcg_func_start(s);
    114 
    115     gen_intermediate_code(env, tb);
    116 
    117     /* generate machine code */
    118     gen_code_buf = tb->tc_ptr;
    119     tb->tb_next_offset[0] = 0xffff;
    120     tb->tb_next_offset[1] = 0xffff;
    121     s->tb_next_offset = tb->tb_next_offset;
    122 #ifdef USE_DIRECT_JUMP
    123     s->tb_jmp_offset = tb->tb_jmp_offset;
    124     s->tb_next = NULL;
    125     /* the following two entries are optional (only used for string ops) */
    126     /* XXX: not used ? */
    127     tb->tb_jmp_offset[2] = 0xffff;
    128     tb->tb_jmp_offset[3] = 0xffff;
    129 #else
    130     s->tb_jmp_offset = NULL;
    131     s->tb_next = tb->tb_next;
    132 #endif
    133 
    134 #ifdef CONFIG_PROFILER
    135     s->tb_count++;
    136     s->interm_time += profile_getclock() - ti;
    137     s->code_time -= profile_getclock();
    138 #endif
    139     gen_code_size = tcg_gen_code(s, gen_code_buf);
    140     *gen_code_size_ptr = gen_code_size;
    141 #ifdef CONFIG_PROFILER
    142     s->code_time += profile_getclock();
    143     s->code_in_len += tb->size;
    144     s->code_out_len += gen_code_size;
    145 #endif
    146 
    147 #ifdef CONFIG_MEMCHECK
    148     /* Save translated PC -> guest PC map into TB. */
    149     if (memcheck_enabled && gen_opc_tpc2gpc_pairs && is_cpu_user(env)) {
    150         tb->tpc2gpc =
    151                 qemu_malloc(gen_opc_tpc2gpc_pairs * 2 * sizeof(uintptr_t));
    152         if (tb->tpc2gpc != NULL) {
    153             memcpy(tb->tpc2gpc, gen_opc_tpc2gpc_ptr,
    154                    gen_opc_tpc2gpc_pairs * 2 * sizeof(uintptr_t));
    155             tb->tpc2gpc_pairs = gen_opc_tpc2gpc_pairs;
    156         }
    157 
    158     }
    159 #endif  // CONFIG_MEMCHECK
    160 
    161 #ifdef DEBUG_DISAS
    162     if (qemu_loglevel_mask(CPU_LOG_TB_OUT_ASM)) {
    163         qemu_log("OUT: [size=%d]\n", *gen_code_size_ptr);
    164         log_disas(tb->tc_ptr, *gen_code_size_ptr);
    165         qemu_log("\n");
    166         qemu_log_flush();
    167     }
    168 #endif
    169     return 0;
    170 }
    171 
    172 /* The cpu state corresponding to 'searched_pc' is restored.
    173  */
    174 int cpu_restore_state(TranslationBlock *tb,
    175                       CPUState *env, unsigned long searched_pc)
    176 {
    177     TCGContext *s = &tcg_ctx;
    178     int j;
    179     unsigned long tc_ptr;
    180 #ifdef CONFIG_PROFILER
    181     int64_t ti;
    182 #endif
    183 
    184 #ifdef CONFIG_PROFILER
    185     ti = profile_getclock();
    186 #endif
    187     tcg_func_start(s);
    188 
    189     gen_intermediate_code_pc(env, tb);
    190 
    191     if (use_icount) {
    192         /* Reset the cycle counter to the start of the block.  */
    193         env->icount_decr.u16.low += tb->icount;
    194         /* Clear the IO flag.  */
    195         env->can_do_io = 0;
    196     }
    197 
    198     /* find opc index corresponding to search_pc */
    199     tc_ptr = (unsigned long)tb->tc_ptr;
    200     if (searched_pc < tc_ptr)
    201         return -1;
    202 
    203     s->tb_next_offset = tb->tb_next_offset;
    204 #ifdef USE_DIRECT_JUMP
    205     s->tb_jmp_offset = tb->tb_jmp_offset;
    206     s->tb_next = NULL;
    207 #else
    208     s->tb_jmp_offset = NULL;
    209     s->tb_next = tb->tb_next;
    210 #endif
    211     j = tcg_gen_code_search_pc(s, (uint8_t *)tc_ptr, searched_pc - tc_ptr);
    212     if (j < 0)
    213         return -1;
    214     /* now find start of instruction before */
    215     while (gen_opc_instr_start[j] == 0)
    216         j--;
    217     env->icount_decr.u16.low -= gen_opc_icount[j];
    218 
    219     restore_state_to_opc(env, tb, j);
    220 
    221 #ifdef CONFIG_PROFILER
    222     s->restore_time += profile_getclock() - ti;
    223     s->restore_count++;
    224 #endif
    225     return 0;
    226 }
    227