gdbserver/ax.h

   1 /* Data structures and functions associated with agent expressions in GDB.
   2    Copyright (C) 2009-2021 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 #include "gdbsupport/agent.h"
  26 #define debug_threads debug_agent
  27 #endif
  28
  29 struct traceframe;
  30
  31 /* Enumeration of the different kinds of things that can happen during
  32    agent expression evaluation.  */
  33
  34 enum eval_result_type
  35   {
  36     expr_eval_no_error,
  37     expr_eval_empty_expression,
  38     expr_eval_empty_stack,
  39     expr_eval_stack_overflow,
  40     expr_eval_stack_underflow,
  41     expr_eval_unhandled_opcode,
  42     expr_eval_unrecognized_opcode,
  43     expr_eval_divide_by_zero,
  44     expr_eval_invalid_goto
  45   };
  46
  47 struct agent_expr
  48 {
  49   int length;
  50
  51   unsigned char *bytes;
  52 };
  53
  54 #ifndef IN_PROCESS_AGENT
  55
  56 /* The packet form of an agent expression consists of an 'X', number
  57    of bytes in expression, a comma, and then the bytes.  */
  58 struct agent_expr *gdb_parse_agent_expr (const char **actparm);
  59
  60 /* Release an agent expression.  */
  61 void gdb_free_agent_expr (struct agent_expr *aexpr);
  62
  63 /* Convert the bytes of an agent expression back into hex digits, so
  64    they can be printed or uploaded.  This allocates the buffer,
  65    callers should free when they are done with it.  */
  66 char *gdb_unparse_agent_expr (struct agent_expr *aexpr);
  67 void emit_prologue (void);
  68 void emit_epilogue (void);
  69 enum eval_result_type compile_bytecodes (struct agent_expr *aexpr);
  70 #endif
  71
  72 /* The context when evaluating agent expression.  */
  73
  74 struct eval_agent_expr_context
  75 {
  76   /* The registers when evaluating agent expression.  */
  77   struct regcache *regcache;
  78   /* The traceframe, if any, when evaluating agent expression.  */
  79   struct traceframe *tframe;
  80   /* The tracepoint, if any, when evaluating agent expression.  */
  81   struct tracepoint *tpoint;
  82 };
  83
  84 enum eval_result_type
  85   gdb_eval_agent_expr (struct eval_agent_expr_context *ctx,
  86                        struct agent_expr *aexpr,
  87                        ULONGEST *rslt);
  88
  89 /* Bytecode compilation function vector.  */
  90
  91 struct emit_ops
  92 {
  93   void (*emit_prologue) (void);
  94   void (*emit_epilogue) (void);
  95   void (*emit_add) (void);
  96   void (*emit_sub) (void);
  97   void (*emit_mul) (void);
  98   void (*emit_lsh) (void);
  99   void (*emit_rsh_signed) (void);
 100   void (*emit_rsh_unsigned) (void);
 101   void (*emit_ext) (int arg);
 102   void (*emit_log_not) (void);
 103   void (*emit_bit_and) (void);
 104   void (*emit_bit_or) (void);
 105   void (*emit_bit_xor) (void);
 106   void (*emit_bit_not) (void);
 107   void (*emit_equal) (void);
 108   void (*emit_less_signed) (void);
 109   void (*emit_less_unsigned) (void);
 110   void (*emit_ref) (int size);
 111   void (*emit_if_goto) (int *offset_p, int *size_p);
 112   void (*emit_goto) (int *offset_p, int *size_p);
 113   void (*write_goto_address) (CORE_ADDR from, CORE_ADDR to, int size);
 114   void (*emit_const) (LONGEST num);
 115   void (*emit_call) (CORE_ADDR fn);
 116   void (*emit_reg) (int reg);
 117   void (*emit_pop) (void);
 118   void (*emit_stack_flush) (void);
 119   void (*emit_zero_ext) (int arg);
 120   void (*emit_swap) (void);
 121   void (*emit_stack_adjust) (int n);
 122
 123   /* Emit code for a generic function that takes one fixed integer
 124      argument and returns a 64-bit int (for instance, tsv getter).  */
 125   void (*emit_int_call_1) (CORE_ADDR fn, int arg1);
 126
 127   /* Emit code for a generic function that takes one fixed integer
 128      argument and a 64-bit int from the top of the stack, and returns
 129      nothing (for instance, tsv setter).  */
 130   void (*emit_void_call_2) (CORE_ADDR fn, int arg1);
 131
 132   /* Emit code specialized for common combinations of compare followed
 133      by a goto.  */
 134   void (*emit_eq_goto) (int *offset_p, int *size_p);
 135   void (*emit_ne_goto) (int *offset_p, int *size_p);
 136   void (*emit_lt_goto) (int *offset_p, int *size_p);
 137   void (*emit_le_goto) (int *offset_p, int *size_p);
 138   void (*emit_gt_goto) (int *offset_p, int *size_p);
 139   void (*emit_ge_goto) (int *offset_p, int *size_p);
 140 };
 141
 142 extern CORE_ADDR current_insn_ptr;
 143 extern int emit_error;
 144
 145 #endif /* GDBSERVER_AX_H */