gdbserver/ax.h

   1 /* Data structures and functions associated with agent expressions in GDB.
   2    Copyright (C) 2009-2020 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program 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
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef GDBSERVER_AX_H
  20 #define GDBSERVER_AX_H
  21
  22 #include "regcache.h"
  23
  24 #ifdef IN_PROCESS_AGENT
  25 #define debug_threads debug_agent
  26 #endif
  27
  28 struct traceframe;
  29
  30 /* Enumeration of the different kinds of things that can happen during
  31    agent expression evaluation.  */
  32
  33 enum eval_result_type
  34   {
  35     expr_eval_no_error,
  36     expr_eval_empty_expression,
  37     expr_eval_empty_stack,
  38     expr_eval_stack_overflow,
  39     expr_eval_stack_underflow,
  40     expr_eval_unhandled_opcode,
  41     expr_eval_unrecognized_opcode,
  42     expr_eval_divide_by_zero,
  43     expr_eval_invalid_goto
  44   };
  45
  46 struct agent_expr
  47 {
  48   int length;
  49
  50   unsigned char *bytes;
  51 };
  52
  53 #ifndef IN_PROCESS_AGENT
  54
  55 /* The packet form of an agent expression consists of an 'X', number
  56    of bytes in expression, a comma, and then the bytes.  */
  57 struct agent_expr *gdb_parse_agent_expr (const char **actparm);
  58
  59 /* Release an agent expression.  */
  60 void gdb_free_agent_expr (struct agent_expr *aexpr);
  61
  62 /* Convert the bytes of an agent expression back into hex digits, so
  63    they can be printed or uploaded.  This allocates the buffer,
  64    callers should free when they are done with it.  */
  65 char *gdb_unparse_agent_expr (struct agent_expr *aexpr);
  66 void emit_prologue (void);
  67 void emit_epilogue (void);
  68 enum eval_result_type compile_bytecodes (struct agent_expr *aexpr);
  69 #endif
  70
  71 /* The context when evaluating agent expression.  */
  72
  73 struct eval_agent_expr_context
  74 {
  75   /* The registers when evaluating agent expression.  */
  76   struct regcache *regcache;
  77   /* The traceframe, if any, when evaluating agent expression.  */
  78   struct traceframe *tframe;
  79   /* The tracepoint, if any, when evaluating agent expression.  */
  80   struct tracepoint *tpoint;
  81 };
  82
  83 enum eval_result_type
  84   gdb_eval_agent_expr (struct eval_agent_expr_context *ctx,
  85                        struct agent_expr *aexpr,
  86                        ULONGEST *rslt);
  87
  88 /* Bytecode compilation function vector.  */
  89
  90 struct emit_ops
  91 {
  92   void (*emit_prologue) (void);
  93   void (*emit_epilogue) (void);
  94   void (*emit_add) (void);
  95   void (*emit_sub) (void);
  96   void (*emit_mul) (void);
  97   void (*emit_lsh) (void);
  98   void (*emit_rsh_signed) (void);
  99   void (*emit_rsh_unsigned) (void);
 100   void (*emit_ext) (int arg);
 101   void (*emit_log_not) (void);
 102   void (*emit_bit_and) (void);
 103   void (*emit_bit_or) (void);
 104   void (*emit_bit_xor) (void);
 105   void (*emit_bit_not) (void);
 106   void (*emit_equal) (void);
 107   void (*emit_less_signed) (void);
 108   void (*emit_less_unsigned) (void);
 109   void (*emit_ref) (int size);
 110   void (*emit_if_goto) (int *offset_p, int *size_p);
 111   void (*emit_goto) (int *offset_p, int *size_p);
 112   void (*write_goto_address) (CORE_ADDR from, CORE_ADDR to, int size);
 113   void (*emit_const) (LONGEST num);
 114   void (*emit_call) (CORE_ADDR fn);
 115   void (*emit_reg) (int reg);
 116   void (*emit_pop) (void);
 117   void (*emit_stack_flush) (void);
 118   void (*emit_zero_ext) (int arg);
 119   void (*emit_swap) (void);
 120   void (*emit_stack_adjust) (int n);
 121
 122   /* Emit code for a generic function that takes one fixed integer
 123      argument and returns a 64-bit int (for instance, tsv getter).  */
 124   void (*emit_int_call_1) (CORE_ADDR fn, int arg1);
 125
 126   /* Emit code for a generic function that takes one fixed integer
 127      argument and a 64-bit int from the top of the stack, and returns
 128      nothing (for instance, tsv setter).  */
 129   void (*emit_void_call_2) (CORE_ADDR fn, int arg1);
 130
 131   /* Emit code specialized for common combinations of compare followed
 132      by a goto.  */
 133   void (*emit_eq_goto) (int *offset_p, int *size_p);
 134   void (*emit_ne_goto) (int *offset_p, int *size_p);
 135   void (*emit_lt_goto) (int *offset_p, int *size_p);
 136   void (*emit_le_goto) (int *offset_p, int *size_p);
 137   void (*emit_gt_goto) (int *offset_p, int *size_p);
 138   void (*emit_ge_goto) (int *offset_p, int *size_p);
 139 };
 140
 141 extern CORE_ADDR current_insn_ptr;
 142 extern int emit_error;
 143
 144 #endif /* GDBSERVER_AX_H */