401 lines
13 KiB
C
401 lines
13 KiB
C
/* Target machine description for generic Motorola 88000, for GDB.
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Copyright 1986, 1987, 1988, 1989, 1990, 1991 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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/* g++ support is not yet included. */
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#define TARGET_BYTE_ORDER BIG_ENDIAN
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/* We cache information about saved registers in the frame structure,
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to save us from having to re-scan function prologues every time
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a register in a non-current frame is accessed. */
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#define EXTRA_FRAME_INFO \
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struct frame_saved_regs *fsr; \
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CORE_ADDR locals_pointer; \
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CORE_ADDR args_pointer;
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/* Zero the frame_saved_regs pointer when the frame is initialized,
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so that FRAME_FIND_SAVED_REGS () will know to allocate and
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initialize a frame_saved_regs struct the first time it is called.
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Set the arg_pointer to -1, which is not valid; 0 and other values
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indicate real, cached values. */
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#define INIT_EXTRA_FRAME_INFO(fromleaf, fi) \
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init_extra_frame_info (fromleaf, fi)
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extern void init_extra_frame_info ();
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#define IEEE_FLOAT
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/* Define this if the C compiler puts an underscore at the front
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of external names before giving them to the linker. */
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#define NAMES_HAVE_UNDERSCORE
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/* Offset from address of function to start of its code.
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Zero on most machines. */
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#define FUNCTION_START_OFFSET 0
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/* Advance PC across any function entry prologue instructions
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to reach some "real" code. */
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#define SKIP_PROLOGUE(frompc) \
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skip_prologue (frompc)
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extern CORE_ADDR skip_prologue ();
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/* The m88k kernel aligns all instructions on 4-byte boundaries. The
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kernel also uses the least significant two bits for its own hocus
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pocus. When gdb receives an address from the kernel, it needs to
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preserve those right-most two bits, but gdb also needs to be careful
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to realize that those two bits are not really a part of the address
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of an instruction. Shrug. */
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#define ADDR_BITS_REMOVE(addr) ((addr) & ~3)
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#define ADDR_BITS_SET(addr) (((addr) | 0x00000002) - 4)
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/* Immediately after a function call, return the saved pc.
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Can't always go through the frames for this because on some machines
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the new frame is not set up until the new function executes
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some instructions. */
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#define SAVED_PC_AFTER_CALL(frame) \
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(ADDR_BITS_REMOVE (read_register (SRP_REGNUM)))
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/* Stack grows downward. */
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#define INNER_THAN <
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/* Sequence of bytes for breakpoint instruction. */
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/* instruction 0xF000D1FF is 'tb0 0,r0,511'
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If Bit bit 0 of r0 is clear (always true),
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initiate exception processing (trap).
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*/
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#define BREAKPOINT {0xF0, 0x00, 0xD1, 0xFF}
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/* Amount PC must be decremented by after a breakpoint.
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This is often the number of bytes in BREAKPOINT
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but not always. */
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#define DECR_PC_AFTER_BREAK 0
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/* Nonzero if instruction at PC is a return instruction. */
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/* 'jmp r1' or 'jmp.n r1' is used to return from a subroutine. */
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#define ABOUT_TO_RETURN(pc) (read_memory_integer (pc, 2) == 0xF800)
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/* Return 1 if P points to an invalid floating point value.
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LEN is the length in bytes. */
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#define INVALID_FLOAT(p, len) IEEE_isNAN(p,len)
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/* Say how long (ordinary) registers are. */
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#define REGISTER_TYPE long
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/* Number of machine registers */
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#define NUM_REGS 38
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/* Initializer for an array of names of registers.
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There should be NUM_REGS strings in this initializer. */
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#define REGISTER_NAMES {\
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"r0",\
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"r1",\
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"r2",\
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"r3",\
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"r4",\
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"r5",\
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"r6",\
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"r7",\
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"r8",\
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"r9",\
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"r10",\
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"r11",\
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"r12",\
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"r13",\
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"r14",\
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"r15",\
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"r16",\
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"r17",\
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"r18",\
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"r19",\
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"r20",\
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"r21",\
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"r22",\
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"r23",\
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"r24",\
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"r25",\
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"r26",\
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"r27",\
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"r28",\
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"r29",\
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"r30",\
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"r31",\
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"psr",\
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"fpsr",\
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"fpcr",\
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"sxip",\
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"snip",\
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"sfip",\
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"vbr",\
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"dmt0",\
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"dmd0",\
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"dma0",\
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"dmt1",\
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"dmd1",\
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"dma1",\
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"dmt2",\
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"dmd2",\
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"dma2",\
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"sr0",\
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"sr1",\
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"sr2",\
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"sr3",\
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"fpecr",\
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"fphs1",\
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"fpls1",\
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"fphs2",\
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"fpls2",\
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"fppt",\
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"fprh",\
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"fprl",\
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"fpit",\
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"fpsr",\
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"fpcr",\
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};
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/* Register numbers of various important registers.
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Note that some of these values are "real" register numbers,
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and correspond to the general registers of the machine,
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and some are "phony" register numbers which are too large
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to be actual register numbers as far as the user is concerned
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but do serve to get the desired values when passed to read_register. */
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#define SRP_REGNUM 1 /* Contains subroutine return pointer */
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#define RV_REGNUM 2 /* Contains simple return values */
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#define SRA_REGNUM 12 /* Contains address of struct return values */
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#define FP_REGNUM 31 /* Reg fetched to locate frame when pgm stops */
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#define SP_REGNUM 31 /* Contains address of top of stack */
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#define SXIP_REGNUM 35 /* Contains Shadow Execute Instruction Pointer */
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#define SNIP_REGNUM 36 /* Contains Shadow Next Instruction Pointer */
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#define PC_REGNUM SXIP_REGNUM /* Program Counter */
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#define NPC_REGNUM SNIP_REGNUM /* Next Program Counter */
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#define PSR_REGNUM 32 /* Processor Status Register */
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#define FPSR_REGNUM 33 /* Floating Point Status Register */
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#define FPCR_REGNUM 34 /* Floating Point Control Register */
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#define SFIP_REGNUM 37 /* Contains Shadow Fetched Intruction pointer */
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#define NNPC_REGNUM SFIP_REGNUM /* Next Next Program Counter */
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/* PSR status bit definitions. */
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#define PSR_MODE 0x80000000
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#define PSR_BYTE_ORDER 0x40000000
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#define PSR_SERIAL_MODE 0x20000000
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#define PSR_CARRY 0x10000000
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#define PSR_SFU_DISABLE 0x000003f0
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#define PSR_SFU1_DISABLE 0x00000008
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#define PSR_MXM 0x00000004
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#define PSR_IND 0x00000002
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#define PSR_SFRZ 0x00000001
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/* BCS requires that the SXIP_REGNUM (or PC_REGNUM) contain the address
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of the next instr to be executed when a breakpoint occurs. Because
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the kernel gets the next instr (SNIP_REGNUM), the instr in SNIP needs
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to be put back into SFIP, and the instr in SXIP should be shifted
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to SNIP */
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/* Are you sitting down? It turns out that the 88K BCS (binary compatibility
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standard) folks originally felt that the debugger should be responsible
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for backing up the IPs, not the kernel (as is usually done). Well, they
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have reversed their decision, and in future releases our kernel will be
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handling the backing up of the IPs. So, eventually, we won't need to
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do the SHIFT_INST_REGS stuff. But, for now, since there are 88K systems out
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there that do need the debugger to do the IP shifting, and since there
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will be systems where the kernel does the shifting, the code is a little
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more complex than perhaps it needs to be (we still go inside SHIFT_INST_REGS,
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and if the shifting hasn't occurred then gdb goes ahead and shifts). */
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#define SHIFT_INST_REGS
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/* Total amount of space needed to store our copies of the machine's
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register state, the array `registers'. */
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#define REGISTER_BYTES (NUM_REGS * sizeof(REGISTER_TYPE))
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/* Index within `registers' of the first byte of the space for
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register N. */
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#define REGISTER_BYTE(N) ((N)*sizeof(REGISTER_TYPE))
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/* Number of bytes of storage in the actual machine representation
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for register N. */
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#define REGISTER_RAW_SIZE(N) (sizeof(REGISTER_TYPE))
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/* Number of bytes of storage in the program's representation
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for register N. */
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#define REGISTER_VIRTUAL_SIZE(N) (sizeof(REGISTER_TYPE))
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/* Largest value REGISTER_RAW_SIZE can have. */
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#define MAX_REGISTER_RAW_SIZE (sizeof(REGISTER_TYPE))
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/* Largest value REGISTER_VIRTUAL_SIZE can have.
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/* Are FPS1, FPS2, FPR "virtual" regisers? */
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#define MAX_REGISTER_VIRTUAL_SIZE (sizeof(REGISTER_TYPE))
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/* Nonzero if register N requires conversion
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from raw format to virtual format. */
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#define REGISTER_CONVERTIBLE(N) (0)
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/* Convert data from raw format for register REGNUM
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to virtual format for register REGNUM. */
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#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,FROM,TO) {bcopy ((FROM), (TO), (sizeof(REGISTER_TYPE)));}
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/* Convert data from virtual format for register REGNUM
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to raw format for register REGNUM. */
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#define REGISTER_CONVERT_TO_RAW(REGNUM,FROM,TO) {bcopy ((FROM), (TO), (sizeof(REGISTER_TYPE)));}
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/* Return the GDB type object for the "standard" data type
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of data in register N. */
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#define REGISTER_VIRTUAL_TYPE(N) (builtin_type_int)
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/* The 88k call/return conventions call for "small" values to be returned
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into consecutive registers starting from r2. */
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#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
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bcopy (&(((char *)REGBUF)[REGISTER_BYTE(RV_REGNUM)]), (VALBUF), TYPE_LENGTH (TYPE))
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#define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
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/* Write into appropriate registers a function return value
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of type TYPE, given in virtual format. */
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#define STORE_RETURN_VALUE(TYPE,VALBUF) \
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write_register_bytes (2*sizeof(void*), (VALBUF), TYPE_LENGTH (TYPE))
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/* In COFF, if PCC says a parameter is a short or a char, do not
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change it to int (it seems the convention is to change it). */
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#define BELIEVE_PCC_PROMOTION 1
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/* Describe the pointer in each stack frame to the previous stack frame
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(its caller). */
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/* FRAME_CHAIN takes a frame's nominal address
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and produces the frame's chain-pointer.
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However, if FRAME_CHAIN_VALID returns zero,
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it means the given frame is the outermost one and has no caller. */
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extern CORE_ADDR frame_chain ();
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extern int frame_chain_valid ();
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extern int frameless_function_invocation ();
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#define FRAME_CHAIN(thisframe) \
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frame_chain (thisframe)
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#define FRAME_CHAIN_VALID(chain, thisframe) \
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frame_chain_valid (chain, thisframe)
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#define FRAMELESS_FUNCTION_INVOCATION(frame, fromleaf) \
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fromleaf = frameless_function_invocation (frame)
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/* Define other aspects of the stack frame. */
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#define FRAME_SAVED_PC(FRAME) \
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frame_saved_pc (FRAME)
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extern CORE_ADDR frame_saved_pc ();
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#define FRAME_ARGS_ADDRESS(fi) \
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frame_args_address (fi)
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extern CORE_ADDR frame_args_address ();
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#define FRAME_LOCALS_ADDRESS(fi) \
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frame_locals_address (fi)
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extern CORE_ADDR frame_locals_address ();
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/* Return number of args passed to a frame.
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Can return -1, meaning no way to tell. */
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#define FRAME_NUM_ARGS(numargs, fi) ((numargs) = -1)
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/* Return number of bytes at start of arglist that are not really args. */
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#define FRAME_ARGS_SKIP 0
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/* Put here the code to store, into a struct frame_saved_regs,
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the addresses of the saved registers of frame described by FRAME_INFO.
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This includes special registers such as pc and fp saved in special
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ways in the stack frame. sp is even more special:
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the address we return for it IS the sp for the next frame. */
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/* On the 88k, parameter registers get stored into the so called "homing"
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area. This *always* happens when you compiled with GCC and use -g.
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Also, (with GCC and -g) the saving of the parameter register values
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always happens right within the function prologue code, so these register
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values can generally be relied upon to be already copied into their
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respective homing slots by the time you will normally try to look at
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them (we hope).
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Note that homing area stack slots are always at *positive* offsets from
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the frame pointer. Thus, the homing area stack slots for the parameter
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registers (passed values) for a given function are actually part of the
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frame area of the caller. This is unusual, but it should not present
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any special problems for GDB.
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Note also that on the 88k, we are only interested in finding the
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registers that might have been saved in memory. This is a subset of
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the whole set of registers because the standard calling sequence allows
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the called routine to clobber many registers.
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We could manage to locate values for all of the so called "preserved"
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registers (some of which may get saved within any particular frame) but
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that would require decoding all of the tdesc information. Tht would be
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nice information for GDB to have, but it is not strictly manditory if we
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can live without the ability to look at values within (or backup to)
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previous frames.
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*/
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#define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
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frame_find_saved_regs (frame_info, &frame_saved_regs)
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/* There is not currently a functioning way to call functions in the
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inferior. */
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/* But if there was this is where we'd put the call dummy. */
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/* #define CALL_DUMMY_LOCATION AFTER_TEXT_END */
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/* When popping a frame on the 88k (say when doing a return command), the
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calling function only expects to have the "preserved" registers restored.
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Thus, those are the only ones that we even try to restore here. */
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#define POP_FRAME pop_frame ()
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extern void pop_frame ();
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