gdb/config/arc/tm-arc.h

   1 /* Parameters for target machine ARC, for GDB, the GNU debugger.
   2    Copyright (C) 1995 Free Software Foundation, Inc.
   3    Contributed by Cygnus Support Corporation.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 /* Byte order is configurable, but this machine runs little-endian.  */
  22 #define TARGET_BYTE_ORDER       LITTLE_ENDIAN
  23
  24 /* We have IEEE floating point, if we have any float at all.  */
  25 #define IEEE_FLOAT
  26
  27 /* Offset from address of function to start of its code.
  28    Zero on most machines.  */
  29 #define FUNCTION_START_OFFSET 0
  30
  31 /* Advance pc across any function entry prologue instructions
  32    to reach some "real" code.  */
  33
  34 #define SKIP_PROLOGUE(pc)       { pc = skip_prologue (pc); }
  35 extern CORE_ADDR skip_prologue ();
  36
  37 /* Sequence of bytes for breakpoint instruction.  */
  38 #define BREAKPOINT {0x01, 0x80, 0xbe, 0x1f}
  39
  40 #define DECR_PC_AFTER_BREAK 4
  41
  42 /* Immediately after a function call, return the saved pc.
  43    Can't always go through the frames for this because on some machines
  44    the new frame is not set up until the new function
  45    executes some instructions.  */
  46
  47 #define SAVED_PC_AFTER_CALL(frame) (read_register (BLINK_REGNUM))
  48
  49 /* Stack grows upward */
  50
  51 #define INNER_THAN <
  52
  53 /* Nonzero if instruction at pc is a return instruction.  */
  54
  55 #define ABOUT_TO_RETURN(pc) (read_memory_integer(pc,4) == 0x380f8000)
  56
  57 /* Say how long (ordinary) registers are.  This is a piece of bogosity
  58    used in push_word and a few other places; REGISTER_RAW_SIZE is the
  59    real way to know how big a register is.  */
  60 #define REGISTER_SIZE 4
  61
  62 /* Number of machine registers */
  63 #define NUM_REGS 91
  64
  65 /* Initializer for an array of names of registers.
  66    There should be NUM_REGS strings in this initializer.  */
  67
  68 #define REGISTER_NAMES \
  69 { \
  70     /*  0 */ "r0",  "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7", \
  71     /*  8 */ "r8",  "r9",  "r10", "r11", "r12", "r13", "r14", "r15", \
  72     /* 16 */ "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23", \
  73     /* 24 */ "r24", "r25", "r26", "fp", "sp", "ilink1", "ilink2", "blink", \
  74     /* 32 */ "r32", "r33", "r34", "r35", "r36", "r37", "r38", "r39", \
  75     /* 40 */ "r40", "r41", "r42", "r43", "r44", "r45", "r46", "r47", \
  76     /* 48 */ "r48", "r49", "r50", "r51", "r52", "r53", "r54", "r55", \
  77     /* 56 */ "r56", "mlo", "mmid", "mhi", "lp_count", \
  78     /* 61 */ "status", "sema", "lp_start", "lp_end", "identity", "debug", \
  79     /* 67 */ "aux10", "aux11", "aux12", "aux13", "aux14", \
  80     /* 72 */ "aux15", "aux16", "aux17", "aux18", "aux19", \
  81     /* 77 */ "aux1a", "aux1b", "aux1c", "aux1d", "aux1e", \
  82     /* 82 */ "aux1f", "aux20", "aux21", "aux22", \
  83     /* 86 */ "aux30", "aux31", "aux32", "aux33", "aux40", \
  84     /* 91 */ "pc" \
  85 }
  86
  87 /* Register numbers of various important registers (used to index
  88    into arrays of register names and register values).  */
  89
  90 #define R0_REGNUM   0      /* First local register              */
  91 #define R59_REGNUM 59      /* Last local register               */
  92 #define FP_REGNUM  27      /* Contains address of executing stack frame */
  93 #define SP_REGNUM  28      /* stack pointer */
  94 #define BLINK_REGNUM 31    /* link register */
  95 #define STA_REGNUM 61      /* processor status word */
  96 #define PC_REGNUM  91      /* instruction pointer */
  97 #define AUX_BEG_REGNUM  61 /* aux reg begins */
  98 #define AUX_END_REGNUM  90 /* aux reg ends, pc not real aux reg */
  99
 100 #define AUX_REG_MAP \
 101 { \
 102    {  0,  1,  2,  3,  4,  5, \
 103      16, -1, -1, -1, -1, \
 104      -1, -1, -1, -1, -1, \
 105      -1, -1, -1, -1, 30, \
 106      -1, 32, 33, -1, \
 107       48, 49, 50, 51, 64, \
 108       0 \
 109     }, \
 110    {  0,  1,  2,  3,  4,  5, \
 111      16, -1, -1, -1, -1, \
 112      -1, -1, -1, -1, -1, \
 113      -1, -1, -1, -1, 30, \
 114      31, 32, 33, -1, \
 115      -1, -1, -1, -1, -1, \
 116       0 \
 117     }, \
 118    {  0,  1,  2,  3,  4,  5, \
 119       16, 17, 18, 19, 20, \
 120       21, 22, 23, 24, 25, \
 121       26, 27, 28, 29, 30, \
 122       31, 32, 33, 34, \
 123      -1, -1, -1, -1, -1, \
 124       0 \
 125     } \
 126 }
 127
 128 #define PFP_REGNUM R0_REGNUM    /* Previous frame pointer       */
 129
 130 /* Total amount of space needed to store our copies of the machine's
 131    register state, the array `registers'.  */
 132 #define REGISTER_BYTES (91*4)
 133
 134 /* Index within `registers' of the first byte of the space for register N.  */
 135 #define REGISTER_BYTE(N) (4*(N))
 136
 137 /* Number of bytes of storage in the actual machine representation
 138    for register N. */
 139 #define REGISTER_RAW_SIZE(N) 4
 140
 141 /* Number of bytes of storage in the program's representation for register N. */
 142 #define REGISTER_VIRTUAL_SIZE(N) 4
 143
 144 /* Largest value REGISTER_RAW_SIZE can have.  */
 145 #define MAX_REGISTER_RAW_SIZE 4
 146
 147 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 148 #define MAX_REGISTER_VIRTUAL_SIZE 4
 149
 150 /* Return the GDB type object for the "standard" data type
 151    of data in register N.  */
 152 #define REGISTER_VIRTUAL_TYPE(N) (builtin_type_int)
 153
 154 \f
 155 /* Macros for understanding function return values... */
 156
 157 /* Does the specified function use the "struct returning" convention
 158    or the "value returning" convention?  The "value returning" convention
 159    almost invariably returns the entire value in registers.  The
 160    "struct returning" convention often returns the entire value in
 161    memory, and passes a pointer (out of or into the function) saying
 162    where the value (is or should go).
 163
 164    Since this sometimes depends on whether it was compiled with GCC,
 165    this is also an argument.  This is used in call_function to build a
 166    stack, and in value_being_returned to print return values.
 167
 168    On arc, a structure is always retunred with pointer in r??. */
 169
 170 #define USE_STRUCT_CONVENTION(gcc_p, type) 1
 171
 172 /* Extract from an array REGBUF containing the (raw) register state
 173    a function return value of type TYPE, and copy that, in virtual format,
 174    into VALBUF.  This is only called if USE_STRUCT_CONVENTION for this
 175    type is 0.
 176 */
 177 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 178         memcpy(VALBUF, REGBUF+REGISTER_BYTE(R0_REGNUM), TYPE_LENGTH (TYPE))
 179
 180 /* If USE_STRUCT_CONVENTION produces a 1,
 181    extract from an array REGBUF containing the (raw) register state
 182    the address in which a function should return its structure value,
 183    as a CORE_ADDR (or an expression that can be used as one). */
 184 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) \
 185    (error("Don't know where large structure is returned on arc"), 0)
 186
 187 /* Write into appropriate registers a function return value
 188    of type TYPE, given in virtual format, for "value returning" functions.
 189    For 'return' command:  not (yet) implemented for arc.  */
 190 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 191     error ("Returning values from functions is not implemented in arc gdb")
 192
 193 /* Store the address of the place in which to copy the structure the
 194    subroutine will return.  This is called from call_function. */
 195 #define STORE_STRUCT_RETURN(ADDR, SP) \
 196     error ("Returning values from functions is not implemented in arc gdb")
 197
 198 \f
 199 /* Describe the pointer in each stack frame to the previous stack frame
 200    (its caller).  */
 201
 202 /* FRAME_CHAIN takes a frame's nominal address
 203    and produces the frame's chain-pointer.
 204    However, if FRAME_CHAIN_VALID returns zero,
 205    it means the given frame is the outermost one and has no caller.  */
 206
 207 /* We cache information about saved registers in the frame structure,
 208    to save us from having to re-scan function prologues every time
 209    a register in a non-current frame is accessed.  */
 210
 211 #define EXTRA_FRAME_INFO \
 212         struct frame_saved_regs *fsr; \
 213         CORE_ADDR arg_pointer;
 214
 215 /* Zero the frame_saved_regs pointer when the frame is initialized,
 216    so that FRAME_FIND_SAVED_REGS () will know to allocate and
 217    initialize a frame_saved_regs struct the first time it is called.
 218    Set the arg_pointer to -1, which is not valid; 0 and other values
 219    indicate real, cached values.  */
 220
 221 #define INIT_EXTRA_FRAME_INFO(fromleaf, fi) \
 222         ((fi)->fsr = 0, (fi)->arg_pointer = -1)
 223
 224 /* On the arc, we get the chain pointer by reading the PFP saved
 225    on the stack. */
 226 /* the PFP and RPC is in fp and fp+4. or it is in fp+4 and fp+8 ??? */
 227
 228 #define FRAME_CHAIN(thisframe) \
 229   (read_memory_integer (FRAME_FP(thisframe), 4))
 230
 231 /* FRAME_CHAIN_VALID returns zero if the given frame is the outermost one
 232    and has no caller.
 233 #define FRAME_CHAIN_VALID(thisframe) \
 234    1
 235
 236 /* A macro that tells us whether the function invocation represented
 237    by FI does not have a frame on the stack associated with it.  If it
 238    does not, FRAMELESS is set to 1, else 0.  */
 239
 240 #define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
 241   do { \
 242     if ((FI)->signal_handler_caller) \
 243       (FRAMELESS) = 0; \
 244     else \
 245       (FRAMELESS) = frameless_look_for_prologue(FI); \
 246   } while (0)
 247
 248 #define FRAME_SAVED_PC(frame) \
 249   (read_memory_integer(FRAME_CHAIN(frame)+8,4))
 250
 251 /* On the ARC, FRAME_ARGS_ADDRESS should return the value of
 252    g14 as passed into the frame, if known.  We need a function for this.
 253    We cache this value in the frame info if we've already looked it up.  */
 254
 255 #define FRAME_ARGS_ADDRESS(fi)  \
 256   (((fi)->arg_pointer != -1)? (fi)->arg_pointer: (fi)->frame + 4)
 257
 258 /* This is the same except it should return 0 when
 259    it does not really know where the args are, rather than guessing.
 260    This value is not cached since it is only used infrequently.  */
 261
 262 #define FRAME_LOCALS_ADDRESS(fi)        (fi)->frame + 4
 263
 264 /* Set NUMARGS to the number of args passed to a frame.
 265    Can return -1, meaning no way to tell.  */
 266
 267 #define FRAME_NUM_ARGS(numargs, fi)     (numargs = -1)
 268
 269 /* Return number of bytes at start of arglist that are not really args.  */
 270
 271 #define FRAME_ARGS_SKIP 0
 272
 273 /* Produce the positions of the saved registers in a stack frame.  */
 274
 275 #define FRAME_FIND_SAVED_REGS(frame_info_addr, sr) \
 276         frame_find_saved_regs (frame_info_addr, &sr)
 277 extern void frame_find_saved_regs();            /* See arc-tdep.c */
 278
 279 \f
 280 /* Things needed for making calls to functions in the inferior process */
 281 #define PUSH_DUMMY_FRAME \
 282         push_dummy_frame ()
 283
 284 /* Discard from the stack the innermost frame, restoring all registers.  */
 285 #define POP_FRAME \
 286         pop_frame ()
 287
 288 /* This sequence of words is the instructions  bl xxxx, flag 1 */
 289 #define CALL_DUMMY { 0x28000000, 0x1fbe8001 }
 290 #define CALL_DUMMY_LENGTH 8
 291
 292 /* Start execution at beginning of dummy */
 293 #define CALL_DUMMY_START_OFFSET 0
 294
 295 /* Insert the specified number of args and function address
 296    into a call sequence of the above form stored at 'dummyname'.*/
 297 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p) \
 298 { \
 299         int from, to, delta, loc; \
 300         loc = (int)(read_register (SP_REGNUM) - CALL_DUMMY_LENGTH); \
 301         from = loc + 4; \
 302         to = (int)(fun); \
 303         delta = (to - from) >> 2; \
 304         *((char *)(dummyname) + 1) = (delta & 0x1); \
 305         *((char *)(dummyname) + 2) = ((delta >> 1) & 0xff); \
 306         *((char *)(dummyname) + 3) = ((delta >> 9) & 0xff); \
 307         *((char *)(dummyname) + 4) = ((delta >> 17) & 0x7); \
 308 }
 309