disas/disas-target.c

   1 /*
   2  * Routines for target instruction disassembly.
   3  * SPDX-License-Identifier: GPL-2.0-or-later
   4  */
   5
   6 #include "qemu/osdep.h"
   7 #include "disas/disas.h"
   8 #include "disas/capstone.h"
   9 #include "exec/translator.h"
  10 #include "disas-internal.h"
  11
  12
  13 static int translator_read_memory(bfd_vma memaddr, bfd_byte *myaddr,
  14                                   int length, struct disassemble_info *info)
  15 {
  16     const DisasContextBase *db = info->application_data;
  17     return translator_st(db, myaddr, memaddr, length) ? 0 : EIO;
  18 }
  19
  20 void target_disas(FILE *out, CPUState *cpu, const struct DisasContextBase *db)
  21 {
  22     uint64_t code = db->pc_first;
  23     size_t size = translator_st_len(db);
  24     uint64_t pc;
  25     int count;
  26     CPUDebug s;
  27
  28     disas_initialize_debug_target(&s, cpu);
  29     s.info.read_memory_func = translator_read_memory;
  30     s.info.application_data = (void *)db;
  31     s.info.fprintf_func = fprintf;
  32     s.info.stream = out;
  33     s.info.buffer_vma = code;
  34     s.info.buffer_length = size;
  35     s.info.show_opcodes = true;
  36
  37     if (s.info.cap_arch >= 0 && cap_disas_target(&s.info, code, size)) {
  38         return;
  39     }
  40
  41     if (s.info.print_insn == NULL) {
  42         s.info.print_insn = print_insn_od_target;
  43     }
  44
  45     for (pc = code; size > 0; pc += count, size -= count) {
  46         fprintf(out, "0x%08" PRIx64 ":  ", pc);
  47         count = s.info.print_insn(pc, &s.info);
  48         fprintf(out, "\n");
  49         if (count < 0) {
  50             break;
  51         }
  52         if (size < count) {
  53             fprintf(out,
  54                     "Disassembler disagrees with translator over instruction "
  55                     "decoding\n"
  56                     "Please report this to qemu-devel@nongnu.org\n");
  57             break;
  58         }
  59     }
  60 }
  61
  62 #ifdef CONFIG_PLUGIN
  63 static void plugin_print_address(bfd_vma addr, struct disassemble_info *info)
  64 {
  65     /* does nothing */
  66 }
  67
  68 /*
  69  * We should only be dissembling one instruction at a time here. If
  70  * there is left over it usually indicates the front end has read more
  71  * bytes than it needed.
  72  */
  73 char *plugin_disas(CPUState *cpu, const DisasContextBase *db,
  74                    uint64_t addr, size_t size)
  75 {
  76     CPUDebug s;
  77     GString *ds = g_string_new(NULL);
  78
  79     disas_initialize_debug_target(&s, cpu);
  80     s.info.read_memory_func = translator_read_memory;
  81     s.info.application_data = (void *)db;
  82     s.info.fprintf_func = disas_gstring_printf;
  83     s.info.stream = (FILE *)ds;  /* abuse this slot */
  84     s.info.buffer_vma = addr;
  85     s.info.buffer_length = size;
  86     s.info.print_address_func = plugin_print_address;
  87
  88     if (s.info.cap_arch >= 0 && cap_disas_plugin(&s.info, addr, size)) {
  89         ; /* done */
  90     } else if (s.info.print_insn) {
  91         s.info.print_insn(addr, &s.info);
  92     } else {
  93         ; /* cannot disassemble -- return empty string */
  94     }
  95
  96     /* Return the buffer, freeing the GString container.  */
  97     return g_string_free(ds, false);
  98 }
  99 #endif /* CONFIG_PLUGIN */