tm-29k.h

早期freebsd实现

/* Parameters for target machine of AMD 29000, for GDB, the GNU debugger.
   Copyright 1990, 1991 Free Software Foundation, Inc.
   Contributed by Cygnus Support.  Written by Jim Kingdon.

This file is part of GDB.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

/* Parameters for an EB29K (a board which plugs into a PC and is
   accessed through EBMON software running on the PC, which we
   use as we'd use a remote stub (see remote-eb.c).

   If gdb is ported to other 29k machines/systems, the
   machine/system-specific parts should be removed from this file (a
   la tm-68k.h).  */

/* Byte order is configurable, but this machine runs big-endian.  */
#define TARGET_BYTE_ORDER BIG_ENDIAN

/* Floating point uses IEEE representations.  */
#define IEEE_FLOAT

/* Recognize our magic number.  */
#define BADMAG(x) ((x).f_magic != 0572)

/* Define this if the C compiler puts an underscore at the front
   of external names before giving them to the linker.  */

#define NAMES_HAVE_UNDERSCORE

/* Offset from address of function to start of its code.
   Zero on most machines.  */

#define FUNCTION_START_OFFSET 0

/* Advance PC across any function entry prologue instructions
   to reach some "real" code.  */

#define SKIP_PROLOGUE(pc) \
  { pc = skip_prologue (pc); }
CORE_ADDR skip_prologue ();

/* Immediately after a function call, return the saved pc.
   Can't go through the frames for this because on some machines
   the new frame is not set up until the new function executes
   some instructions.  */

#define SAVED_PC_AFTER_CALL(frame) (read_register (LR0_REGNUM))

/* I'm not sure about the exact value of this, but based on looking
   at the stack pointer when we get to main this seems to be right.

   This is the register stack; We call it "CONTROL" in GDB for consistency
   with Pyramid.  */
#define CONTROL_END_ADDR 0x80200000

/* Memory stack.  This is for the default register stack size, which is
   only 0x800 bytes.  Perhaps we should let the user specify stack sizes
   (and tell EBMON with the "ZS" command).  */
#define STACK_END_ADDR 0x801ff800

/* Stack grows downward.  */

#define INNER_THAN <

/* Stack must be aligned on 32-bit word boundaries.  */
#define STACK_ALIGN(ADDR) (((ADDR) + 3) & ~3)

/* Sequence of bytes for breakpoint instruction.  */
/* ASNEQ 0x50, gr1, gr1
   The trap number 0x50 is chosen arbitrarily.
   We let the command line (or previously included files) override this
   setting.  */
#ifndef BREAKPOINT
#if TARGET_BYTE_ORDER == BIG_ENDIAN
#define BREAKPOINT {0x72, 0x50, 0x01, 0x01}
#else /* Target is little-endian.  */
#define BREAKPOINT {0x01, 0x01, 0x50, 0x72}
#endif /* Target is little-endian.  */
#endif /* BREAKPOINT */

/* Amount PC must be decremented by after a breakpoint.
   This is often the number of bytes in BREAKPOINT
   but not always.  */

#define DECR_PC_AFTER_BREAK 0

/* Nonzero if instruction at PC is a return instruction.
   On the 29k, this is a "jmpi l0" instruction.  */

#define ABOUT_TO_RETURN(pc) \
  ((read_memory_integer (pc, 4) & 0xff0000ff) == 0xc0000080)

/* Return 1 if P points to an invalid floating point value.  */

#define INVALID_FLOAT(p, len) 0   /* Just a first guess; not checked */

/* Say how long (ordinary) registers are.  */

#define REGISTER_TYPE long

/* Allow the register declarations here to be overridden for remote
   kernel debugging.  */
#if !defined (REGISTER_NAMES)

/* Number of machine registers */

#define NUM_REGS 205

/* Initializer for an array of names of registers.
   There should be NUM_REGS strings in this initializer.

   FIXME, add floating point registers and support here.

   Also note that this list does not attempt to deal with kernel
   debugging (in which the first 32 registers are gr64-gr95).  */

#define REGISTER_NAMES \
{"gr96", "gr97", "gr98", "gr99", "gr100", "gr101", "gr102", "gr103", "gr104", \
 "gr105", "gr106", "gr107", "gr108", "gr109", "gr110", "gr111", "gr112", \
 "gr113", "gr114", "gr115", "gr116", "gr117", "gr118", "gr119", "gr120", \
 "gr121", "gr122", "gr123", "gr124", "gr125", "gr126", "gr127",		 \
 "lr0", "lr1", "lr2", "lr3", "lr4", "lr5", "lr6", "lr7", "lr8", "lr9",   \
 "lr10", "lr11", "lr12", "lr13", "lr14", "lr15", "lr16", "lr17", "lr18", \
 "lr19", "lr20", "lr21", "lr22", "lr23", "lr24", "lr25", "lr26", "lr27", \
 "lr28", "lr29", "lr30", "lr31", "lr32", "lr33", "lr34", "lr35", "lr36", \
 "lr37", "lr38", "lr39", "lr40", "lr41", "lr42", "lr43", "lr44", "lr45", \
 "lr46", "lr47", "lr48", "lr49", "lr50", "lr51", "lr52", "lr53", "lr54", \
 "lr55", "lr56", "lr57", "lr58", "lr59", "lr60", "lr61", "lr62", "lr63", \
 "lr64", "lr65", "lr66", "lr67", "lr68", "lr69", "lr70", "lr71", "lr72", \
 "lr73", "lr74", "lr75", "lr76", "lr77", "lr78", "lr79", "lr80", "lr81", \
 "lr82", "lr83", "lr84", "lr85", "lr86", "lr87", "lr88", "lr89", "lr90", \
 "lr91", "lr92", "lr93", "lr94", "lr95", "lr96", "lr97", "lr98", "lr99", \
 "lr100", "lr101", "lr102", "lr103", "lr104", "lr105", "lr106", "lr107", \
 "lr108", "lr109", "lr110", "lr111", "lr112", "lr113", "lr114", "lr115", \
 "lr116", "lr117", "lr118", "lr119", "lr120", "lr121", "lr122", "lr123", \
 "lr124", "lr125", "lr126", "lr127",					 \
  "AI0", "AI1", "AI2", "AI3", "AI4", "AI5", "AI6", "AI7", "AI8", "AI9",  \
  "AI10", "AI11", "AI12", "AI13", "AI14", "AI15", "FP",			 \
  "bp", "fc", "cr", "q",						 \
  "vab", "ops", "cps", "cfg", "cha", "chd", "chc", "rbp", "tmc", "tmr",	 \
  "pc0", "pc1", "pc2", "mmu", "lru", "fpe", "inte", "fps", "exo", "gr1",  \
  "alu", "ipc", "ipa", "ipb" }

/*
 * Converts an sdb register number to an internal gdb register number.
 * Currently under epi, gr96->0...gr127->31...lr0->32...lr127->159, or...
 * 		  	gr64->0...gr95->31, lr0->32...lr127->159.
 */
#define SDB_REG_TO_REGNUM(value) \
  (((value) >= 96 && (value) <= 127) ? ((value) - 96) : \
   ((value) >= 128 && (value) <=  255) ? ((value) - 128 + LR0_REGNUM) : \
   (value))

/*
 * Provide the processor register numbers of some registers that are
 * expected/written in instructions that might change under different
 * register sets.  Namely, gcc can compile (-mkernel-registers) so that
 * it uses gr64-gr95 in stead of gr96-gr127.
 */
#define MSP_HW_REGNUM	125		/* gr125 */
#define RAB_HW_REGNUM	126		/* gr126 */

/* Convert Processor Special register #x to REGISTER_NAMES register # */
#define SR_REGNUM(x) \
  ((x) < 15  ? VAB_REGNUM + (x)					 \
   : (x) >= 128 && (x) < 131 ? IPC_REGNUM + (x) - 128		 \
   : (x) == 131 ? Q_REGNUM					 \
   : (x) == 132 ? ALU_REGNUM					 \
   : (x) >= 133 && (x) < 136 ? BP_REGNUM + (x) - 133		 \
   : (x) >= 160 && (x) < 163 ? FPE_REGNUM + (x) - 160		 \
   : (x) == 164 ? EXO_REGNUM                                     \
   : (error ("Internal error in SR_REGNUM"), 0))
#define GR96_REGNUM 0
/* Define the return register separately, so it can be overridden for
   kernel procedure calling conventions. */
#define	RETURN_REGNUM	GR96_REGNUM
#define GR1_REGNUM 200
/* This needs to be the memory stack pointer, not the register stack pointer,
   to make call_function work right.  */
#define SP_REGNUM MSP_REGNUM
#define FP_REGNUM 33 /* lr1 */
/* Large Return Pointer (gr123).  */
#define LRP_REGNUM (123 - 96 + GR96_REGNUM)
/* Static link pointer (gr124).  */
#define SLP_REGNUM (124 - 96 + GR96_REGNUM)
/* Memory Stack Pointer (gr125).  */
#define MSP_REGNUM (125 - 96 + GR96_REGNUM)
/* Register allocate bound (gr126).  */
#define RAB_REGNUM (126 - 96 + GR96_REGNUM)
/* Register Free Bound (gr127).  */
#define RFB_REGNUM (127 - 96 + GR96_REGNUM)
/* Register Stack Pointer.  */
#define RSP_REGNUM GR1_REGNUM
#define LR0_REGNUM 32
#define BP_REGNUM 177
#define FC_REGNUM 178
#define CR_REGNUM 179
#define Q_REGNUM 180
#define VAB_REGNUM 181
#define OPS_REGNUM (VAB_REGNUM + 1)
#define CPS_REGNUM (VAB_REGNUM + 2)
#define CFG_REGNUM (VAB_REGNUM + 3)
#define CHA_REGNUM (VAB_REGNUM + 4)
#define CHD_REGNUM (VAB_REGNUM + 5)
#define CHC_REGNUM (VAB_REGNUM + 6)
#define RBP_REGNUM (VAB_REGNUM + 7)
#define TMC_REGNUM (VAB_REGNUM + 8)
#define TMR_REGNUM (VAB_REGNUM + 9)
#define NPC_REGNUM (VAB_REGNUM + 10)  /* pc0 */
#define PC_REGNUM  (VAB_REGNUM + 11)  /* pc1 */
#define PC2_REGNUM (VAB_REGNUM + 12)
#define MMU_REGNUM (VAB_REGNUM + 13)
#define LRU_REGNUM (VAB_REGNUM + 14)
#define FPE_REGNUM (VAB_REGNUM + 15)
#define INTE_REGNUM (VAB_REGNUM + 16)
#define FPS_REGNUM (VAB_REGNUM + 17)
#define EXO_REGNUM (VAB_REGNUM + 18)
/* gr1 is defined above as 200 = VAB_REGNUM + 19 */
#define ALU_REGNUM (VAB_REGNUM + 20)
#define PS_REGNUM  ALU_REGNUM
#define IPC_REGNUM (VAB_REGNUM + 21)
#define IPA_REGNUM (VAB_REGNUM + 22)
#define IPB_REGNUM (VAB_REGNUM + 23)

#endif	/* !defined(REGISTER_NAMES) */

/* Total amount of space needed to store our copies of the machine's
   register state, the array `registers'.  */
#define REGISTER_BYTES (NUM_REGS * 4)

/* Index within `registers' of the first byte of the space for
   register N.  */
#define REGISTER_BYTE(N)  ((N)*4)

/* Number of bytes of storage in the actual machine representation
   for register N.  */

/* All regs are 4 bytes.  */

#define REGISTER_RAW_SIZE(N) (4)

/* Number of bytes of storage in the program's representation
   for register N.  */

/* All regs are 4 bytes.  */

#define REGISTER_VIRTUAL_SIZE(N) (4)

/* Largest value REGISTER_RAW_SIZE can have.  */

#define MAX_REGISTER_RAW_SIZE (4)

/* Largest value REGISTER_VIRTUAL_SIZE can have.  */

#define MAX_REGISTER_VIRTUAL_SIZE (4)

/* Nonzero if register N requires conversion
   from raw format to virtual format.  */

#define REGISTER_CONVERTIBLE(N) (0)

/* Convert data from raw format for register REGNUM
   to virtual format for register REGNUM.  */

#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) \
{ bcopy ((FROM), (TO), 4); }

/* Convert data from virtual format for register REGNUM
   to raw format for register REGNUM.  */

#define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO)	\
{ bcopy ((FROM), (TO), 4); }

/* Return the GDB type object for the "standard" data type
   of data in register N.  */

#define REGISTER_VIRTUAL_TYPE(N) \
  (((N) == PC_REGNUM || (N) == LRP_REGNUM || (N) == SLP_REGNUM         \
    || (N) == MSP_REGNUM || (N) == RAB_REGNUM || (N) == RFB_REGNUM     \
    || (N) == GR1_REGNUM || (N) == FP_REGNUM || (N) == LR0_REGNUM       \
    || (N) == NPC_REGNUM || (N) == PC2_REGNUM)                           \
   ? lookup_pointer_type (builtin_type_void) : builtin_type_int)

/* Store the address of the place in which to copy the structure the
   subroutine will return.  This is called from call_function. */
/* On the 29k the LRP points to the part of the structure beyond the first
   16 words.  */
#define STORE_STRUCT_RETURN(ADDR, SP) \
  write_register (LRP_REGNUM, (ADDR) + 16 * 4);

/* Should call_function allocate stack space for a struct return?  */
/* On the 29k objects over 16 words require the caller to allocate space.  */
#define USE_STRUCT_CONVENTION(gcc_p, type) (TYPE_LENGTH (type) > 16 * 4)

/* Extract from an array REGBUF containing the (raw) register state
   a function return value of type TYPE, and copy that, in virtual format,
   into VALBUF.  */

#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF)	      \
  {    	       	       	       	       	       	       	       	       	   \
    int reg_length = TYPE_LENGTH (TYPE);				   \
    if (reg_length > 16 * 4)						   \
      {									   \
	reg_length = 16 * 4;						   \
	read_memory (*((int *)(REGBUF) + LRP_REGNUM), (VALBUF) + 16 * 4,   \
		     TYPE_LENGTH (TYPE) - 16 * 4);			   \
      }									   \
    bcopy (((int *)(REGBUF))+RETURN_REGNUM, (VALBUF), reg_length);	   \
  }

/* Write into appropriate registers a function return value
   of type TYPE, given in virtual format.  */

#define STORE_RETURN_VALUE(TYPE,VALBUF) \
  {									  \
    int reg_length = TYPE_LENGTH (TYPE);				  \
    if (reg_length > 16 * 4)						  \
      {									  \
        reg_length = 16 * 4;						  \
        write_memory (read_register (LRP_REGNUM),			  \
		      (char *)(VALBUF) + 16 * 4,			  \
		      TYPE_LENGTH (TYPE) - 16 * 4);			  \
      }									  \
    write_register_bytes (REGISTER_BYTE (RETURN_REGNUM), (char *)(VALBUF),  \
			  TYPE_LENGTH (TYPE));				  \
  }

/* The am29k user's guide documents well what the stacks look like.
   But what isn't so clear there is how this interracts with the
   symbols, or with GDB.
   In the following saved_msp, saved memory stack pointer (which functions
   as a memory frame pointer), means either
   a register containing the memory frame pointer or, in the case of
   functions with fixed size memory frames (i.e. those who don't use
   alloca()), the result of the calculation msp + msize.

   LOC_ARG, LOC_LOCAL - For GCC, these are relative to saved_msp.
     For high C, these are relative to msp (making alloca impossible).
   LOC_REGISTER, LOC_REGPARM - The register number is the number at the
     time the function is running (after the prologue), or in the case
     of LOC_REGPARM, may be a register number in the range 160-175.

   The compilers do things like store an argument into memory, and then put out
   a LOC_ARG for it, or put it into global registers and put out a
   LOC_REGPARM.  Thus is it important to execute the first line of