gdb/tm-mips.h

   1 /* Definitions to make GDB run on a mips box under 4.3bsd.
   2    Copyright 1986, 1987, 1989, 1991, 1992, 1993 Free Software Foundation, Inc.
   3    Contributed by Per Bothner (bothner@cs.wisc.edu) at U.Wisconsin
   4    and by Alessandro Forin (af@cs.cmu.edu) at CMU..
   5
   6 This file is part of GDB.
   7
   8 This program is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2 of the License, or
  11 (at your option) any later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program; if not, write to the Free Software
  20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  21
  22 #include "coff/sym.h"           /* Needed for PDR below.  */
  23 #include "coff/symconst.h"
  24
  25 #if !defined (TARGET_BYTE_ORDER)
  26 #define TARGET_BYTE_ORDER LITTLE_ENDIAN
  27 #endif
  28
  29 /* Floating point is IEEE compliant */
  30 #define IEEE_FLOAT
  31
  32 /* Some MIPS boards are provided both with and without a floating
  33    point coprocessor; we provide a user settable variable to tell gdb
  34    whether there is one or not.  */
  35 extern int mips_fpu;
  36
  37 /* Offset from address of function to start of its code.
  38    Zero on most machines.  */
  39
  40 #define FUNCTION_START_OFFSET 0
  41
  42 /* Advance PC across any function entry prologue instructions
  43    to reach some "real" code.  */
  44
  45 #define SKIP_PROLOGUE(pc)       pc = mips_skip_prologue(pc)
  46
  47 /* Immediately after a function call, return the saved pc.
  48    Can't always go through the frames for this because on some machines
  49    the new frame is not set up until the new function executes
  50    some instructions.  */
  51
  52 #define SAVED_PC_AFTER_CALL(frame)      read_register(RA_REGNUM)
  53
  54 /* Are we currently handling a signal */
  55
  56 #define IN_SIGTRAMP(pc, name)   in_sigtramp(pc, name)
  57
  58 /* Address of end of stack space.  */
  59
  60 #define STACK_END_ADDR (0x7ffff000)
  61
  62 /* Stack grows downward.  */
  63
  64 #define INNER_THAN <
  65
  66 #define BIG_ENDIAN 4321
  67 #if TARGET_BYTE_ORDER == BIG_ENDIAN
  68 #define BREAKPOINT {0, 0x5, 0, 0xd}
  69 #else
  70 #define BREAKPOINT {0xd, 0, 0x5, 0}
  71 #endif
  72
  73 /* Amount PC must be decremented by after a breakpoint.
  74    This is often the number of bytes in BREAKPOINT
  75    but not always.  */
  76
  77 #define DECR_PC_AFTER_BREAK 0
  78
  79 /* Nonzero if instruction at PC is a return instruction. "j ra" on mips. */
  80
  81 #define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 4) == 0x3e00008)
  82
  83 /* Return 1 if P points to an invalid floating point value. */
  84
  85 #define INVALID_FLOAT(p,l)      isa_NAN(p,l)
  86
  87 /* Say how long (all) registers are.  */
  88
  89 #define REGISTER_TYPE long
  90
  91 /* Number of machine registers */
  92
  93 #define NUM_REGS 80
  94
  95 /* Initializer for an array of names of registers.
  96    There should be NUM_REGS strings in this initializer.  */
  97
  98 #define REGISTER_NAMES  \
  99     {   "zero", "at",   "v0",   "v1",   "a0",   "a1",   "a2",   "a3", \
 100         "t0",   "t1",   "t2",   "t3",   "t4",   "t5",   "t6",   "t7", \
 101         "s0",   "s1",   "s2",   "s3",   "s4",   "s5",   "s6",   "s7", \
 102         "t8",   "t9",   "k0",   "k1",   "gp",   "sp",   "s8",   "ra", \
 103         "sr",   "lo",   "hi",   "bad",  "cause","pc",    \
 104         "f0",   "f1",   "f2",   "f3",   "f4",   "f5",   "f6",   "f7", \
 105         "f8",   "f9",   "f10",  "f11",  "f12",  "f13",  "f14",  "f15", \
 106         "f16",  "f17",  "f18",  "f19",  "f20",  "f21",  "f22",  "f23",\
 107         "f24",  "f25",  "f26",  "f27",  "f28",  "f29",  "f30",  "f31",\
 108         "fsr",  "fir",  "fp",   "inx",  "rand", "tlblo","ctxt", "tlbhi",\
 109         "epc",  "prid"\
 110     }
 111
 112 /* Register numbers of various important registers.
 113    Note that some of these values are "real" register numbers,
 114    and correspond to the general registers of the machine,
 115    and some are "phony" register numbers which are too large
 116    to be actual register numbers as far as the user is concerned
 117    but do serve to get the desired values when passed to read_register.  */
 118
 119 #define ZERO_REGNUM 0           /* read-only register, always 0 */
 120 #define A0_REGNUM 4             /* Loc of first arg during a subr call */
 121 #define SP_REGNUM 29            /* Contains address of top of stack */
 122 #define RA_REGNUM 31            /* Contains return address value */
 123 #define PS_REGNUM 32            /* Contains processor status */
 124 #define HI_REGNUM 34            /* Multiple/divide temp */
 125 #define LO_REGNUM 33            /* ... */
 126 #define BADVADDR_REGNUM 35      /* bad vaddr for addressing exception */
 127 #define CAUSE_REGNUM 36         /* describes last exception */
 128 #define PC_REGNUM 37            /* Contains program counter */
 129 #define FP0_REGNUM 38           /* Floating point register 0 (single float) */
 130 #define FCRCS_REGNUM 70         /* FP control/status */
 131 #define FCRIR_REGNUM 71         /* FP implementation/revision */
 132 #define FP_REGNUM 72            /* Pseudo register that contains true address of executing stack frame */
 133 #define FIRST_EMBED_REGNUM 73   /* First supervisor register for embedded use */
 134 #define LAST_EMBED_REGNUM 79    /* Last one */
 135
 136 /* Define DO_REGISTERS_INFO() to do machine-specific formatting
 137    of register dumps. */
 138
 139 #define DO_REGISTERS_INFO(_regnum, fp) mips_do_registers_info(_regnum, fp)
 140
 141 /* Total amount of space needed to store our copies of the machine's
 142    register state, the array `registers'.  */
 143 #define REGISTER_BYTES (NUM_REGS*4)
 144
 145 /* Index within `registers' of the first byte of the space for
 146    register N.  */
 147
 148 #define REGISTER_BYTE(N) ((N) * 4)
 149
 150 /* Number of bytes of storage in the actual machine representation
 151    for register N.  On mips, all regs are 4 bytes.  */
 152
 153 #define REGISTER_RAW_SIZE(N) 4
 154
 155 /* Number of bytes of storage in the program's representation
 156    for register N.  On mips, all regs are 4 bytes.  */
 157
 158 #define REGISTER_VIRTUAL_SIZE(N) 4
 159
 160 /* Largest value REGISTER_RAW_SIZE can have.  */
 161
 162 #define MAX_REGISTER_RAW_SIZE 4
 163
 164 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 165
 166 #define MAX_REGISTER_VIRTUAL_SIZE 4
 167
 168 /* Nonzero if register N requires conversion
 169    from raw format to virtual format.  */
 170
 171 #define REGISTER_CONVERTIBLE(N) 0
 172
 173 /* Convert data from raw format for register REGNUM
 174    to virtual format for register REGNUM.  */
 175
 176 #define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO)     \
 177   bcopy ((FROM), (TO), 4);
 178
 179 /* Convert data from virtual format for register REGNUM
 180    to raw format for register REGNUM.  */
 181
 182 #define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) \
 183   bcopy ((FROM), (TO), 4);
 184
 185 /* Return the GDB type object for the "standard" data type
 186    of data in register N.  */
 187
 188 #define REGISTER_VIRTUAL_TYPE(N) \
 189         (((N) >= FP0_REGNUM && (N) < FP0_REGNUM+32)  \
 190          ? builtin_type_float : builtin_type_int) \
 191
 192 /* Store the address of the place in which to copy the structure the
 193    subroutine will return.  This is called from call_function. */
 194
 195 #define STORE_STRUCT_RETURN(addr, sp) \
 196   { sp = push_word(sp, addr);}
 197
 198 /* Extract from an array REGBUF containing the (raw) register state
 199    a function return value of type TYPE, and copy that, in virtual format,
 200    into VALBUF.  XXX floats */
 201
 202 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 203   bcopy (REGBUF + REGISTER_BYTE ((TYPE_CODE (TYPE) == TYPE_CODE_FLT && mips_fpu) ? FP0_REGNUM : 2), VALBUF, TYPE_LENGTH (TYPE))
 204
 205 /* Write into appropriate registers a function return value
 206    of type TYPE, given in virtual format.  */
 207
 208 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 209   write_register_bytes (REGISTER_BYTE ((TYPE_CODE (TYPE) == TYPE_CODE_FLT && mips_fpu) ? FP0_REGNUM : 2), VALBUF, TYPE_LENGTH (TYPE))
 210
 211 /* Extract from an array REGBUF containing the (raw) register state
 212    the address in which a function should return its structure value,
 213    as a CORE_ADDR (or an expression that can be used as one).  */
 214
 215 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF+16))
 216
 217 /* Structures are returned by ref in extra arg0 */
 218 #define USE_STRUCT_CONVENTION(gcc_p, type)      1
 219
 220 \f
 221 /* Describe the pointer in each stack frame to the previous stack frame
 222    (its caller).  */
 223
 224 /* FRAME_CHAIN takes a frame's nominal address
 225    and produces the frame's chain-pointer. */
 226
 227 #define FRAME_CHAIN(thisframe) (FRAME_ADDR)mips_frame_chain(thisframe)
 228
 229 /* Define other aspects of the stack frame.  */
 230
 231
 232 /* A macro that tells us whether the function invocation represented
 233    by FI does not have a frame on the stack associated with it.  If it
 234    does not, FRAMELESS is set to 1, else 0.  */
 235 /* We handle this differently for mips, and maybe we should not */
 236
 237 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS)  {(FRAMELESS) = 0;}
 238
 239 /* Saved Pc.  */
 240
 241 #define FRAME_SAVED_PC(FRAME)   (mips_frame_saved_pc(FRAME))
 242
 243 #define FRAME_ARGS_ADDRESS(fi)  (fi)->frame
 244
 245 #define FRAME_LOCALS_ADDRESS(fi) (fi)->frame
 246
 247 /* Return number of args passed to a frame.
 248    Can return -1, meaning no way to tell.  */
 249
 250 #define FRAME_NUM_ARGS(num, fi) (num = mips_frame_num_args(fi))
 251
 252 /* Return number of bytes at start of arglist that are not really args.  */
 253
 254 #define FRAME_ARGS_SKIP 0
 255
 256 /* Put here the code to store, into a struct frame_saved_regs,
 257    the addresses of the saved registers of frame described by FRAME_INFO.
 258    This includes special registers such as pc and fp saved in special
 259    ways in the stack frame.  sp is even more special:
 260    the address we return for it IS the sp for the next frame.  */
 261
 262 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) ( \
 263   (frame_saved_regs) = *(frame_info)->saved_regs, \
 264   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame)
 265
 266 \f
 267 /* Things needed for making the inferior call functions.  */
 268
 269 /* Stack has strict alignment. However, use PUSH_ARGUMENTS
 270    to take care of it. */
 271 /*#define STACK_ALIGN(addr)     (((addr)+3)&~3)*/
 272
 273 #define PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr) \
 274     sp = mips_push_arguments(nargs, args, sp, struct_return, struct_addr)
 275
 276 /* Push an empty stack frame, to record the current PC, etc.  */
 277
 278 #define PUSH_DUMMY_FRAME        mips_push_dummy_frame()
 279
 280 /* Discard from the stack the innermost frame, restoring all registers.  */
 281
 282 #define POP_FRAME               mips_pop_frame()
 283
 284 #define MK_OP(op,rs,rt,offset) (((op)<<26)|((rs)<<21)|((rt)<<16)|(offset))
 285 #define CALL_DUMMY_SIZE (16*4)
 286 #define Dest_Reg 2
 287 #define CALL_DUMMY {\
 288  MK_OP(0,RA_REGNUM,0,8),        /* jr $ra # Fake ABOUT_TO_RETURN ...*/\
 289  0,                             /* nop    #  ... to stop raw backtrace*/\
 290  0x27bd0000,                    /* addu sp,?0 # Pseudo prologue */\
 291 /* Start here: */\
 292  MK_OP(061,SP_REGNUM,12,0),     /* lwc1 $f12,0(sp) # Reload FP regs*/\
 293  MK_OP(061,SP_REGNUM,13,4),     /* lwc1 $f13,4(sp) */\
 294  MK_OP(061,SP_REGNUM,14,8),     /* lwc1 $f14,8(sp) */\
 295  MK_OP(061,SP_REGNUM,15,12),    /* lwc1 $f15,12(sp) */\
 296  MK_OP(043,SP_REGNUM,4,0),      /* lw $r4,0(sp) # Reload first 4 args*/\
 297  MK_OP(043,SP_REGNUM,5,4),      /* lw $r5,4(sp) */\
 298  MK_OP(043,SP_REGNUM,6,8),      /* lw $r6,8(sp) */\
 299  MK_OP(043,SP_REGNUM,7,12),     /* lw $r7,12(sp) */\
 300  (017<<26)| (Dest_Reg << 16),   /* lui $r31,<target upper 16 bits>*/\
 301  MK_OP(13,Dest_Reg,Dest_Reg,0), /* ori $r31,$r31,<lower 16 bits>*/ \
 302  (Dest_Reg<<21) | (31<<11) | 9, /* jalr $r31 */\
 303  MK_OP(043,SP_REGNUM,7,12),     /* lw $r7,12(sp) */\
 304  0x5000d,                       /* bpt */\
 305 }
 306
 307 #define CALL_DUMMY_START_OFFSET 12
 308
 309 /* Insert the specified number of args and function address
 310    into a call sequence of the above form stored at DUMMYNAME.  */
 311
 312 #define FIX_CALL_DUMMY(dummyname, start_sp, fun, nargs, args, rettype, gcc_p)\
 313   do \
 314     { \
 315       ((int*)(dummyname))[11] |= ((unsigned long)(fun)) >> 16; \
 316       ((int*)(dummyname))[12] |= (unsigned short)(fun); \
 317       if (! mips_fpu) \
 318         { \
 319           ((int *) (dummyname))[3] = 0; \
 320           ((int *) (dummyname))[4] = 0; \
 321           ((int *) (dummyname))[5] = 0; \
 322           ((int *) (dummyname))[6] = 0; \
 323         } \
 324     } \
 325   while (0)
 326
 327 /* There's a mess in stack frame creation.  See comments in blockframe.c
 328    near reference to INIT_FRAME_PC_FIRST.  */
 329
 330 #define INIT_FRAME_PC(fromleaf, prev) /* nada */
 331
 332 #define INIT_FRAME_PC_FIRST(fromleaf, prev) \
 333   (prev)->pc = ((fromleaf) ? SAVED_PC_AFTER_CALL ((prev)->next) : \
 334               (prev)->next ? FRAME_SAVED_PC ((prev)->next) : read_pc ());
 335
 336 /* Special symbol found in blocks associated with routines.  We can hang
 337    mips_extra_func_info_t's off of this.  */
 338
 339 #define MIPS_EFI_SYMBOL_NAME "__GDB_EFI_INFO__"
 340
 341 /* Specific information about a procedure.
 342    This overlays the MIPS's PDR records,
 343    mipsread.c (ab)uses this to save memory */
 344
 345 typedef struct mips_extra_func_info {
 346         long    numargs;        /* number of args to procedure (was iopt) */
 347         PDR     pdr;            /* Procedure descriptor record */
 348 } *mips_extra_func_info_t;
 349
 350 #define EXTRA_FRAME_INFO \
 351   mips_extra_func_info_t proc_desc; \
 352   int num_args;\
 353   struct frame_saved_regs *saved_regs;
 354
 355 #define INIT_EXTRA_FRAME_INFO(fromleaf, fci) init_extra_frame_info(fci)
 356
 357 #define PRINT_EXTRA_FRAME_INFO(fi) \
 358   { \
 359     if (fi && fi->proc_desc && fi->proc_desc->pdr.framereg < NUM_REGS) \
 360       printf_filtered (" frame pointer is at %s+%d\n", \
 361                        reg_names[fi->proc_desc->pdr.framereg], \
 362                                  fi->proc_desc->pdr.frameoffset); \
 363   }
 364
 365 /* It takes two values to specify a frame on the MIPS.  Sigh.
 366
 367    In fact, at the moment, the *PC* is the primary value that sets up
 368    a frame.  The PC is looked up to see what function it's in; symbol
 369    information from that function tells us which register is the frame
 370    pointer base, and what offset from there is the "virtual frame pointer".
 371    (This is usually an offset from SP.)  FIXME -- this should be cleaned
 372    up so that the primary value is the SP, and the PC is used to disambiguate
 373    multiple functions with the same SP that are at different stack levels. */
 374
 375 #define SETUP_ARBITRARY_FRAME(argc, argv) setup_arbitrary_frame (argc, argv)
 376 /* FIXME:  Depends on equivalence between FRAME and "struct frame_info *",
 377    and equivalence between CORE_ADDR and FRAME_ADDR. */
 378 extern struct frame_info *setup_arbitrary_frame PARAMS ((int, CORE_ADDR *));
 379
 380 #define STAB_REG_TO_REGNUM(num) ((num) < 32 ? (num) : (num)+FP0_REGNUM-32)