gdb/arm-tdep.h

   1 /* Common target dependent code for GDB on ARM systems.
   2    Copyright (C) 2002-2022 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 ARM_TDEP_H
  20 #define ARM_TDEP_H
  21
  22 /* Forward declarations.  */
  23 struct regset;
  24 struct address_space;
  25 struct get_next_pcs;
  26 struct arm_get_next_pcs;
  27 struct gdb_get_next_pcs;
  28
  29 /* Set to true if the 32-bit mode is in use.  */
  30
  31 extern bool arm_apcs_32;
  32
  33 #include "gdbarch.h"
  34 #include "arch/arm.h"
  35 #include "infrun.h"
  36
  37 #include <vector>
  38
  39 /* Number of machine registers.  The only define actually required
  40    is gdbarch_num_regs.  The other definitions are used for documentation
  41    purposes and code readability.  */
  42 /* For 26 bit ARM code, a fake copy of the PC is placed in register 25 (PS)
  43    (and called PS for processor status) so the status bits can be cleared
  44    from the PC (register 15).  For 32 bit ARM code, a copy of CPSR is placed
  45    in PS.  */
  46 #define NUM_FREGS       8       /* Number of floating point registers.  */
  47 #define NUM_SREGS       2       /* Number of status registers.  */
  48 #define NUM_GREGS       16      /* Number of general purpose registers.  */
  49
  50
  51
  52 /* Type of floating-point code in use by inferior.  There are really 3 models
  53    that are traditionally supported (plus the endianness issue), but gcc can
  54    only generate 2 of those.  The third is APCS_FLOAT, where arguments to
  55    functions are passed in floating-point registers.
  56
  57    In addition to the traditional models, VFP adds two more.
  58
  59    If you update this enum, don't forget to update fp_model_strings in
  60    arm-tdep.c.  */
  61
  62 enum arm_float_model
  63 {
  64   ARM_FLOAT_AUTO,       /* Automatic detection.  Do not set in tdep.  */
  65   ARM_FLOAT_SOFT_FPA,   /* Traditional soft-float (mixed-endian on LE ARM).  */
  66   ARM_FLOAT_FPA,        /* FPA co-processor.  GCC calling convention.  */
  67   ARM_FLOAT_SOFT_VFP,   /* Soft-float with pure-endian doubles.  */
  68   ARM_FLOAT_VFP,        /* Full VFP calling convention.  */
  69   ARM_FLOAT_LAST        /* Keep at end.  */
  70 };
  71
  72 /* ABI used by the inferior.  */
  73 enum arm_abi_kind
  74 {
  75   ARM_ABI_AUTO,
  76   ARM_ABI_APCS,
  77   ARM_ABI_AAPCS,
  78   ARM_ABI_LAST
  79 };
  80
  81 /* Convention for returning structures.  */
  82
  83 enum struct_return
  84 {
  85   pcc_struct_return,            /* Return "short" structures in memory.  */
  86   reg_struct_return             /* Return "short" structures in registers.  */
  87 };
  88
  89 /* Target-dependent structure in gdbarch.  */
  90 struct arm_gdbarch_tdep : gdbarch_tdep_base
  91 {
  92   /* The ABI for this architecture.  It should never be set to
  93      ARM_ABI_AUTO.  */
  94   enum arm_abi_kind arm_abi {};
  95
  96   enum arm_float_model fp_model {}; /* Floating point calling conventions.  */
  97
  98   bool have_fpa_registers = false;      /* Does the target report the FPA registers?  */
  99   bool have_wmmx_registers = false;     /* Does the target report the WMMX registers?  */
 100   /* The number of VFP registers reported by the target.  It is zero
 101      if VFP registers are not supported.  */
 102   int vfp_register_count = 0;
 103   bool have_s_pseudos = false;  /* Are we synthesizing the single precision
 104                                    VFP registers?  */
 105   int s_pseudo_base = 0;        /* Register number for the first S pseudo
 106                                    register.  */
 107   int s_pseudo_count = 0;       /* Number of S pseudo registers.  */
 108   bool have_q_pseudos = false;  /* Are we synthesizing the quad precision
 109                                    Q (NEON or MVE) registers?  Requires
 110                                    have_s_pseudos.  */
 111   int q_pseudo_base = 0;        /* Register number for the first quad
 112                                    precision pseudo register.  */
 113   int q_pseudo_count = 0;       /* Number of quad precision pseudo
 114                                    registers.  */
 115   bool have_neon = false;       /* Do we have a NEON unit?  */
 116
 117   bool have_mve = false;        /* Do we have a MVE extension?  */
 118   int mve_vpr_regnum = 0;       /* MVE VPR register number.  */
 119   int mve_pseudo_base = 0;      /* Number of the first MVE pseudo register.  */
 120   int mve_pseudo_count = 0;     /* Total number of MVE pseudo registers.  */
 121
 122   bool have_pacbti = false;     /* True if we have the ARMv8.1-m PACBTI
 123                                    extensions.  */
 124   int pacbti_pseudo_base = 0;   /* Number of the first PACBTI pseudo
 125                                    register.  */
 126   int pacbti_pseudo_count = 0;  /* Total number of PACBTI pseudo registers.  */
 127
 128   int m_profile_msp_regnum = ARM_SP_REGNUM;     /* M-profile MSP register number.  */
 129   int m_profile_psp_regnum = ARM_SP_REGNUM;     /* M-profile PSP register number.  */
 130
 131   /* Secure and Non-secure stack pointers with security extension.  */
 132   int m_profile_msp_ns_regnum = ARM_SP_REGNUM;  /* M-profile MSP_NS register number.  */
 133   int m_profile_psp_ns_regnum = ARM_SP_REGNUM;  /* M-profile PSP_NS register number.  */
 134   int m_profile_msp_s_regnum = ARM_SP_REGNUM;   /* M-profile MSP_S register number.  */
 135   int m_profile_psp_s_regnum = ARM_SP_REGNUM;   /* M-profile PSP_S register number.  */
 136
 137   int tls_regnum = 0;           /* Number of the tpidruro register.  */
 138
 139   bool is_m = false;            /* Does the target follow the "M" profile.  */
 140   bool have_sec_ext = false;    /* Do we have security extensions?  */
 141   CORE_ADDR lowest_pc = 0;      /* Lowest address at which instructions
 142                                    will appear.  */
 143
 144   const gdb_byte *arm_breakpoint = nullptr;     /* Breakpoint pattern for an ARM insn.  */
 145   int arm_breakpoint_size = 0;  /* And its size.  */
 146   const gdb_byte *thumb_breakpoint = nullptr;   /* Breakpoint pattern for a Thumb insn.  */
 147   int thumb_breakpoint_size = 0;        /* And its size.  */
 148
 149   /* If the Thumb breakpoint is an undefined instruction (which is
 150      affected by IT blocks) rather than a BKPT instruction (which is
 151      not), then we need a 32-bit Thumb breakpoint to preserve the
 152      instruction count in IT blocks.  */
 153   const gdb_byte *thumb2_breakpoint = nullptr;
 154   int thumb2_breakpoint_size = 0;
 155
 156   int jb_pc = 0;                        /* Offset to PC value in jump buffer.
 157                                    If this is negative, longjmp support
 158                                    will be disabled.  */
 159   size_t jb_elt_size = 0;               /* And the size of each entry in the buf.  */
 160
 161   /* Convention for returning structures.  */
 162   enum struct_return struct_return {};
 163
 164   /* ISA-specific data types.  */
 165   struct type *arm_ext_type = nullptr;
 166   struct type *neon_double_type = nullptr;
 167   struct type *neon_quad_type = nullptr;
 168
 169    /* syscall record.  */
 170   int (*arm_syscall_record) (struct regcache *regcache,
 171                              unsigned long svc_number) = nullptr;
 172 };
 173
 174 /* Structures used for displaced stepping.  */
 175
 176 /* The maximum number of temporaries available for displaced instructions.  */
 177 #define DISPLACED_TEMPS                 16
 178 /* The maximum number of modified instructions generated for one single-stepped
 179    instruction, including the breakpoint (usually at the end of the instruction
 180    sequence) and any scratch words, etc.  */
 181 #define ARM_DISPLACED_MODIFIED_INSNS    8
 182
 183 struct arm_displaced_step_copy_insn_closure
 184   : public displaced_step_copy_insn_closure
 185 {
 186   ULONGEST tmp[DISPLACED_TEMPS];
 187   int rd;
 188   int wrote_to_pc;
 189   union
 190   {
 191     struct
 192     {
 193       int xfersize;
 194       int rn;                      /* Writeback register.  */
 195       unsigned int immed : 1;      /* Offset is immediate.  */
 196       unsigned int writeback : 1;  /* Perform base-register writeback.  */
 197       unsigned int restore_r4 : 1; /* Used r4 as scratch.  */
 198     } ldst;
 199
 200     struct
 201     {
 202       unsigned long dest;
 203       unsigned int link : 1;
 204       unsigned int exchange : 1;
 205       unsigned int cond : 4;
 206     } branch;
 207
 208     struct
 209     {
 210       unsigned int regmask;
 211       int rn;
 212       CORE_ADDR xfer_addr;
 213       unsigned int load : 1;
 214       unsigned int user : 1;
 215       unsigned int increment : 1;
 216       unsigned int before : 1;
 217       unsigned int writeback : 1;
 218       unsigned int cond : 4;
 219     } block;
 220
 221     struct
 222     {
 223       unsigned int immed : 1;
 224     } preload;
 225
 226     struct
 227     {
 228       /* If non-NULL, override generic SVC handling (e.g. for a particular
 229          OS).  */
 230       int (*copy_svc_os) (struct gdbarch *gdbarch, struct regcache *regs,
 231                           arm_displaced_step_copy_insn_closure *dsc);
 232     } svc;
 233   } u;
 234
 235   /* The size of original instruction, 2 or 4.  */
 236   unsigned int insn_size;
 237   /* True if the original insn (and thus all replacement insns) are Thumb
 238      instead of ARM.   */
 239   unsigned int is_thumb;
 240
 241   /* The slots in the array is used in this way below,
 242      - ARM instruction occupies one slot,
 243      - Thumb 16 bit instruction occupies one slot,
 244      - Thumb 32-bit instruction occupies *two* slots, one part for each.  */
 245   unsigned long modinsn[ARM_DISPLACED_MODIFIED_INSNS];
 246   int numinsns;
 247   CORE_ADDR insn_addr;
 248   CORE_ADDR scratch_base;
 249   void (*cleanup) (struct gdbarch *, struct regcache *,
 250                    arm_displaced_step_copy_insn_closure *);
 251 };
 252
 253 /* Values for the WRITE_PC argument to displaced_write_reg.  If the register
 254    write may write to the PC, specifies the way the CPSR T bit, etc. is
 255    modified by the instruction.  */
 256
 257 enum pc_write_style
 258 {
 259   BRANCH_WRITE_PC,
 260   BX_WRITE_PC,
 261   LOAD_WRITE_PC,
 262   ALU_WRITE_PC,
 263   CANNOT_WRITE_PC
 264 };
 265
 266 extern void
 267   arm_process_displaced_insn (struct gdbarch *gdbarch, CORE_ADDR from,
 268                               CORE_ADDR to, struct regcache *regs,
 269                               arm_displaced_step_copy_insn_closure *dsc);
 270 extern void
 271   arm_displaced_init_closure (struct gdbarch *gdbarch, CORE_ADDR from,
 272                               CORE_ADDR to,
 273                               arm_displaced_step_copy_insn_closure *dsc);
 274 extern ULONGEST
 275   displaced_read_reg (regcache *regs, arm_displaced_step_copy_insn_closure *dsc,
 276                       int regno);
 277 extern void
 278   displaced_write_reg (struct regcache *regs,
 279                        arm_displaced_step_copy_insn_closure *dsc, int regno,
 280                        ULONGEST val, enum pc_write_style write_pc);
 281
 282 CORE_ADDR arm_skip_stub (struct frame_info *, CORE_ADDR);
 283
 284 ULONGEST arm_get_next_pcs_read_memory_unsigned_integer (CORE_ADDR memaddr,
 285                                                         int len,
 286                                                         int byte_order);
 287
 288 CORE_ADDR arm_get_next_pcs_addr_bits_remove (struct arm_get_next_pcs *self,
 289                                              CORE_ADDR val);
 290
 291 int arm_get_next_pcs_is_thumb (struct arm_get_next_pcs *self);
 292
 293 std::vector<CORE_ADDR> arm_software_single_step (struct regcache *);
 294 int arm_is_thumb (struct regcache *regcache);
 295 int arm_frame_is_thumb (struct frame_info *frame);
 296
 297 extern void arm_displaced_step_fixup (struct gdbarch *,
 298                                       displaced_step_copy_insn_closure *,
 299                                       CORE_ADDR, CORE_ADDR, struct regcache *);
 300
 301 /* Return the bit mask in ARM_PS_REGNUM that indicates Thumb mode.  */
 302 extern int arm_psr_thumb_bit (struct gdbarch *);
 303
 304 /* Is the instruction at the given memory address a Thumb or ARM
 305    instruction?  */
 306 extern int arm_pc_is_thumb (struct gdbarch *, CORE_ADDR);
 307
 308 extern int arm_process_record (struct gdbarch *gdbarch,
 309                                struct regcache *regcache, CORE_ADDR addr);
 310 /* Functions exported from arm-bsd-tdep.h.  */
 311
 312 /* Return the appropriate register set for the core section identified
 313    by SECT_NAME and SECT_SIZE.  */
 314
 315 extern void
 316   armbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
 317                                        iterate_over_regset_sections_cb *cb,
 318                                        void *cb_data,
 319                                        const struct regcache *regcache);
 320
 321 /* Get the correct Arm target description with given FP hardware type.  */
 322 const target_desc *arm_read_description (arm_fp_type fp_type, bool tls);
 323
 324 /* Get the correct Arm M-Profile target description with given hardware
 325    type.  */
 326 const target_desc *arm_read_mprofile_description (arm_m_profile_type m_type);
 327
 328 #endif /* arm-tdep.h */