666 lines
26 KiB
C
666 lines
26 KiB
C
/* Parameters for target machine of AMD 29000, for GDB, the GNU debugger.
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Copyright 1990, 1991 Free Software Foundation, Inc.
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Contributed by Cygnus Support. Written by Jim Kingdon.
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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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/* Parameters for an EB29K (a board which plugs into a PC and is
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accessed through EBMON software running on the PC, which we
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use as we'd use a remote stub (see remote-eb.c).
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If gdb is ported to other 29k machines/systems, the
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machine/system-specific parts should be removed from this file (a
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la tm-68k.h). */
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/* Byte order is configurable, but this machine runs big-endian. */
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#define TARGET_BYTE_ORDER BIG_ENDIAN
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/* Floating point uses IEEE representations. */
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#define IEEE_FLOAT
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/* Recognize our magic number. */
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#define BADMAG(x) ((x).f_magic != 0572)
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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(pc) \
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{ pc = skip_prologue (pc); }
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CORE_ADDR skip_prologue ();
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/* Immediately after a function call, return the saved pc.
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Can't 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) (read_register (LR0_REGNUM))
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/* I'm not sure about the exact value of this, but based on looking
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at the stack pointer when we get to main this seems to be right.
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This is the register stack; We call it "CONTROL" in GDB for consistency
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with Pyramid. */
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#define CONTROL_END_ADDR 0x80200000
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/* Memory stack. This is for the default register stack size, which is
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only 0x800 bytes. Perhaps we should let the user specify stack sizes
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(and tell EBMON with the "ZS" command). */
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#define STACK_END_ADDR 0x801ff800
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/* Stack grows downward. */
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#define INNER_THAN <
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/* Stack must be aligned on 32-bit word boundaries. */
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#define STACK_ALIGN(ADDR) (((ADDR) + 3) & ~3)
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/* Sequence of bytes for breakpoint instruction. */
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/* ASNEQ 0x50, gr1, gr1
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The trap number 0x50 is chosen arbitrarily. */
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#if TARGET_BYTE_ORDER == BIG_ENDIAN
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#define BREAKPOINT {0x72, 0x50, 0x01, 0x01}
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#else /* Target is little-endian. */
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#define BREAKPOINT {0x01, 0x01, 0x50, 0x72}
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#endif /* Target is little-endian. */
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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 4
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/* Nonzero if instruction at PC is a return instruction.
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On the 29k, this is a "jmpi l0" instruction. */
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#define ABOUT_TO_RETURN(pc) \
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((read_memory_integer (pc, 4) & 0xff0000ff) == 0xc0000080)
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/* Return 1 if P points to an invalid floating point value. */
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#define INVALID_FLOAT(p, len) 0 /* Just a first guess; not checked */
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/* Say how long (ordinary) registers are. */
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#define REGISTER_TYPE long
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/* Allow the register declarations here to be overridden for remote
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kernel debugging. */
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#if !defined (REGISTER_NAMES)
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/* Number of machine registers */
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#define NUM_REGS 205
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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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FIXME, add floating point registers and support here.
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Also note that this list does not attempt to deal with kernel
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debugging (in which the first 32 registers are gr64-gr95). */
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#define REGISTER_NAMES \
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{"gr96", "gr97", "gr98", "gr99", "gr100", "gr101", "gr102", "gr103", "gr104", \
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"gr105", "gr106", "gr107", "gr108", "gr109", "gr110", "gr111", "gr112", \
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"gr113", "gr114", "gr115", "gr116", "gr117", "gr118", "gr119", "gr120", \
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"gr121", "gr122", "gr123", "gr124", "gr125", "gr126", "gr127", \
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"lr0", "lr1", "lr2", "lr3", "lr4", "lr5", "lr6", "lr7", "lr8", "lr9", \
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"lr10", "lr11", "lr12", "lr13", "lr14", "lr15", "lr16", "lr17", "lr18", \
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"lr19", "lr20", "lr21", "lr22", "lr23", "lr24", "lr25", "lr26", "lr27", \
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"lr28", "lr29", "lr30", "lr31", "lr32", "lr33", "lr34", "lr35", "lr36", \
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"lr37", "lr38", "lr39", "lr40", "lr41", "lr42", "lr43", "lr44", "lr45", \
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"lr46", "lr47", "lr48", "lr49", "lr50", "lr51", "lr52", "lr53", "lr54", \
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"lr55", "lr56", "lr57", "lr58", "lr59", "lr60", "lr61", "lr62", "lr63", \
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"lr64", "lr65", "lr66", "lr67", "lr68", "lr69", "lr70", "lr71", "lr72", \
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"lr73", "lr74", "lr75", "lr76", "lr77", "lr78", "lr79", "lr80", "lr81", \
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"lr82", "lr83", "lr84", "lr85", "lr86", "lr87", "lr88", "lr89", "lr90", \
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"lr91", "lr92", "lr93", "lr94", "lr95", "lr96", "lr97", "lr98", "lr99", \
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"lr100", "lr101", "lr102", "lr103", "lr104", "lr105", "lr106", "lr107", \
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"lr108", "lr109", "lr110", "lr111", "lr112", "lr113", "lr114", "lr115", \
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"lr116", "lr117", "lr118", "lr119", "lr120", "lr121", "lr122", "lr123", \
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"lr124", "lr125", "lr126", "lr127", \
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"AI0", "AI1", "AI2", "AI3", "AI4", "AI5", "AI6", "AI7", "AI8", "AI9", \
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"AI10", "AI11", "AI12", "AI13", "AI14", "AI15", "FP", \
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"bp", "fc", "cr", "q", \
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"vab", "ops", "cps", "cfg", "cha", "chd", "chc", "rbp", "tmc", "tmr", \
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"pc0", "pc1", "pc2", "mmu", "lru", "fpe", "int", "fps", "exo", "gr1", \
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"alu", "ipc", "ipa", "ipb" }
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/* Convert Processor Special register #x to REGISTER_NAMES register # */
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#define SR_REGNUM(x) \
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((x) < 15 ? VAB_REGNUM + (x) \
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: (x) >= 128 && (x) < 131 ? IPC_REGNUM + (x) - 128 \
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: (x) == 131 ? Q_REGNUM \
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: (x) == 132 ? ALU_REGNUM \
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: (x) >= 133 && (x) < 136 ? BP_REGNUM + (x) - 133 \
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: (x) >= 160 && (x) < 163 ? FPE_REGNUM + (x) - 160 \
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: (x) == 164 ? EXO_REGNUM \
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: (error ("Internal error in SR_REGNUM"), 0))
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#define GR96_REGNUM 0
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/* Define the return register separately, so it can be overridden for
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kernel procedure calling conventions. */
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#define RETURN_REGNUM GR96_REGNUM
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#define GR1_REGNUM 200
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/* This needs to be the memory stack pointer, not the register stack pointer,
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to make call_function work right. */
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#define SP_REGNUM MSP_REGNUM
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#define FP_REGNUM 33 /* lr1 */
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/* Large Return Pointer (gr123). */
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#define LRP_REGNUM (123 - 96 + GR96_REGNUM)
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/* Static link pointer (gr124). */
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#define SLP_REGNUM (124 - 96 + GR96_REGNUM)
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/* Memory Stack Pointer (gr125). */
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#define MSP_REGNUM (125 - 96 + GR96_REGNUM)
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/* Register allocate bound (gr126). */
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#define RAB_REGNUM (126 - 96 + GR96_REGNUM)
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/* Register Free Bound (gr127). */
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#define RFB_REGNUM (127 - 96 + GR96_REGNUM)
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/* Register Stack Pointer. */
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#define RSP_REGNUM GR1_REGNUM
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#define LR0_REGNUM 32
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#define BP_REGNUM 177
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#define FC_REGNUM 178
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#define CR_REGNUM 179
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#define Q_REGNUM 180
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#define VAB_REGNUM 181
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#define OPS_REGNUM (VAB_REGNUM + 1)
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#define CPS_REGNUM (VAB_REGNUM + 2)
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#define CFG_REGNUM (VAB_REGNUM + 3)
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#define CHA_REGNUM (VAB_REGNUM + 4)
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#define CHD_REGNUM (VAB_REGNUM + 5)
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#define CHC_REGNUM (VAB_REGNUM + 6)
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#define RBP_REGNUM (VAB_REGNUM + 7)
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#define TMC_REGNUM (VAB_REGNUM + 8)
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#define TMR_REGNUM (VAB_REGNUM + 9)
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#define NPC_REGNUM (VAB_REGNUM + 10) /* pc0 */
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#define PC_REGNUM (VAB_REGNUM + 11) /* pc1 */
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#define PC2_REGNUM (VAB_REGNUM + 12)
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#define MMU_REGNUM (VAB_REGNUM + 13)
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#define LRU_REGNUM (VAB_REGNUM + 14)
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#define FPE_REGNUM (VAB_REGNUM + 15)
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#define INT_REGNUM (VAB_REGNUM + 16)
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#define FPS_REGNUM (VAB_REGNUM + 17)
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#define EXO_REGNUM (VAB_REGNUM + 18)
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/* gr1 is defined above as 200 = VAB_REGNUM + 19 */
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#define ALU_REGNUM (VAB_REGNUM + 20)
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#define PS_REGNUM ALU_REGNUM
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#define IPC_REGNUM (VAB_REGNUM + 21)
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#define IPA_REGNUM (VAB_REGNUM + 22)
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#define IPB_REGNUM (VAB_REGNUM + 23)
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#endif /* !defined(REGISTER_NAMES) */
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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 * 4)
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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)*4)
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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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/* All regs are 4 bytes. */
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#define REGISTER_RAW_SIZE(N) (4)
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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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/* All regs are 4 bytes. */
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#define REGISTER_VIRTUAL_SIZE(N) (4)
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/* Largest value REGISTER_RAW_SIZE can have. */
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#define MAX_REGISTER_RAW_SIZE (4)
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/* Largest value REGISTER_VIRTUAL_SIZE can have. */
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#define MAX_REGISTER_VIRTUAL_SIZE (4)
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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) \
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{ bcopy ((FROM), (TO), 4); }
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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) \
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{ bcopy ((FROM), (TO), 4); }
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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) \
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(((N) == PC_REGNUM || (N) == LRP_REGNUM || (N) == SLP_REGNUM \
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|| (N) == MSP_REGNUM || (N) == RAB_REGNUM || (N) == RFB_REGNUM \
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|| (N) == GR1_REGNUM || (N) == FP_REGNUM || (N) == LR0_REGNUM \
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|| (N) == NPC_REGNUM || (N) == PC2_REGNUM) \
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? lookup_pointer_type (builtin_type_void) : builtin_type_int)
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/* Store the address of the place in which to copy the structure the
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subroutine will return. This is called from call_function. */
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/* On the 29k the LRP points to the part of the structure beyond the first
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16 words. */
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#define STORE_STRUCT_RETURN(ADDR, SP) \
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write_register (LRP_REGNUM, (ADDR) + 16 * 4);
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/* Should call_function allocate stack space for a struct return? */
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/* On the 29k objects over 16 words require the caller to allocate space. */
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#define USE_STRUCT_CONVENTION(gcc_p, type) (TYPE_LENGTH (type) > 16 * 4)
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/* Extract from an array REGBUF containing the (raw) register state
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a function return value of type TYPE, and copy that, in virtual format,
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into VALBUF. */
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#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
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{ \
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int reg_length = TYPE_LENGTH (TYPE); \
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if (reg_length > 16 * 4) \
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{ \
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reg_length = 16 * 4; \
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read_memory (*((int *)(REGBUF) + LRP_REGNUM), (VALBUF) + 16 * 4, \
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TYPE_LENGTH (TYPE) - 16 * 4); \
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} \
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bcopy (((int *)(REGBUF))+RETURN_REGNUM, (VALBUF), reg_length); \
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}
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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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{ \
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int reg_length = TYPE_LENGTH (TYPE); \
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if (reg_length > 16 * 4) \
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{ \
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reg_length = 16 * 4; \
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write_memory (read_register (LRP_REGNUM), \
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(char *)(VALBUF) + 16 * 4, \
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TYPE_LENGTH (TYPE) - 16 * 4); \
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} \
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write_register_bytes (REGISTER_BYTE (RETURN_REGNUM), (char *)(VALBUF), \
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TYPE_LENGTH (TYPE)); \
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}
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/* The am29k user's guide documents well what the stacks look like.
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But what isn't so clear there is how this interracts with the
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symbols, or with GDB.
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In the following saved_msp, saved memory stack pointer (which functions
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as a memory frame pointer), means either
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a register containing the memory frame pointer or, in the case of
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functions with fixed size memory frames (i.e. those who don't use
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alloca()), the result of the calculation msp + msize.
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LOC_ARG, LOC_LOCAL - For GCC, these are relative to saved_msp.
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For high C, these are relative to msp (making alloca impossible).
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LOC_REGISTER, LOC_REGPARM - The register number is the number at the
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time the function is running (after the prologue), or in the case
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of LOC_REGPARM, may be a register number in the range 160-175.
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The compilers do things like store an argument into memory, and then put out
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a LOC_ARG for it, or put it into global registers and put out a
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LOC_REGPARM. Thus is it important to execute the first line of
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code (i.e. the line of the open brace, i.e. the prologue) of a function
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before trying to print arguments or anything.
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The following diagram attempts to depict what is going on in memory
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(see also the _am29k user's guide_) and also how that interacts with
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GDB frames. We arbitrarily pick fci->frame to point the same place
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as the register stack pointer; since we set it ourself in
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INIT_EXTRA_FRAME_INFO, and access it only through the FRAME_*
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macros, it doesn't really matter exactly how we
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do it. However, note that FRAME_FP is used in two ways in GDB:
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(1) as a "magic cookie" which uniquely identifies frames (even over
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calls to the inferior), (2) (in PC_IN_CALL_DUMMY [ON_STACK])
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as the value of SP_REGNUM before the dummy frame was pushed. These
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two meanings would be incompatible for the 29k if we defined
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CALL_DUMMY_LOCATION == ON_STACK (but we don't, so don't worry about it).
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Also note that "lr1" below, while called a frame pointer
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in the user's guide, has only one function: To determine whether
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registers need to be filled in the function epilogue.
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Consider the code:
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< call bar>
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loc1: . . .
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bar: sub gr1,gr1,rsize_b
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. . .
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add mfp,msp,0
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sub msp,msp,msize_b
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. . .
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< call foo >
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loc2: . . .
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foo: sub gr1,gr1,rsize_f
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. . .
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add mfp,msp,0
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sub msp,msp,msize_f
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. . .
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loc3: < suppose the inferior stops here >
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memory stack register stack
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| | |____________|
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| | |____loc1____|
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+------->|___________| | | ^
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| | ^ | | locals_b | |
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| | | | |____________| |
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| | | | | | | rsize_b
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| | | msize_b | | args_to_f | |
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| | | | |____________| |
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| | | | |____lr1_____| V
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| | V | |____loc2____|<----------------+
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| +--->|___________|<---------mfp | ^ |
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| | | ^ | | locals_f | | |
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| | | | msize_f | |____________| | |
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| | | | | | | | rsize_f |
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| | | V | | args | | |
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| | |___________|<msp |____________| | |
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| | |_____lr1____| V |
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| | |___garbage__| <- gr1 <----+ |
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| | | |
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| | | |
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| | pc=loc3 | |
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| | | |
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| | | |
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| | frame cache | |
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| | |_________________| | |
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| | |rsize=rsize_b | | |
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| | |msize=msize_b | | |
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+---|--------saved_msp | | |
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| |frame------------------------------------|---+
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| |pc=loc2 | |
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| |_________________| |
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| |rsize=rsize_f | |
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| |msize=msize_f | |
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+--------saved_msp | |
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|frame------------------------------------+
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|pc=loc3 |
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|_________________|
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So, is that sufficiently confusing? Welcome to the 29000.
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Notes:
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* The frame for foo uses a memory frame pointer but the frame for
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bar does not. In the latter case the saved_msp is
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computed by adding msize to the saved_msp of the
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next frame.
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* msize is in the frame cache only for high C's sake. */
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void read_register_stack ();
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long read_register_stack_integer ();
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#define EXTRA_FRAME_INFO \
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CORE_ADDR saved_msp; \
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unsigned int rsize; \
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unsigned int msize;
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/* Because INIT_FRAME_PC gets passed fromleaf, that's where we init
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not only ->pc and ->frame, but all the extra stuff, when called from
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get_prev_frame_info, that is. */
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#define INIT_EXTRA_FRAME_INFO(fromleaf, fci) \
|
||
init_extra_frame_info(fci);
|
||
void init_extra_frame_info ();
|
||
#define INIT_FRAME_PC(fromleaf, fci) \
|
||
init_frame_pc(fromleaf, fci);
|
||
void init_frame_pc ();
|
||
|
||
/* FRAME_CHAIN takes a FRAME
|
||
and produces the frame's chain-pointer.
|
||
|
||
However, if FRAME_CHAIN_VALID returns zero,
|
||
it means the given frame is the outermost one and has no caller. */
|
||
|
||
/* On the 29k, the nominal address of a frame is the address on the
|
||
register stack of the return address (the one next to the incoming
|
||
arguments, not down at the bottom so nominal address == stack pointer).
|
||
|
||
GDB expects "nominal address" to equal contents of FP_REGNUM,
|
||
at least when it comes time to create the innermost frame.
|
||
However, that doesn't work for us, so when creating the innermost
|
||
frame we set ->frame ourselves in INIT_EXTRA_FRAME_INFO. */
|
||
|
||
/* These are mostly dummies for the 29k because INIT_FRAME_PC
|
||
sets prev->frame instead. */
|
||
#define FRAME_CHAIN(thisframe) (0)
|
||
|
||
/* Not sure how to figure out where the bottom frame is. There is
|
||
no frame for start. In my tests so far the
|
||
pc has been outside the text segment, though, so check for that.
|
||
FIXME!!!
|
||
However, allow a pc in a call dummy. */
|
||
#define FRAME_CHAIN_VALID(chain, thisframe) \
|
||
(outside_startup_file (FRAME_SAVED_PC (thisframe)))
|
||
|
||
/* Define other aspects of the stack frame. */
|
||
|
||
/* A macro that tells us whether the function invocation represented
|
||
by FI does not have a frame on the stack associated with it. If it
|
||
does not, FRAMELESS is set to 1, else 0. */
|
||
#define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
|
||
(FRAMELESS) = frameless_look_for_prologue(FI)
|
||
|
||
/* Saved pc (i.e. return address). */
|
||
#define FRAME_SAVED_PC(fraim) \
|
||
(read_register_stack_integer ((fraim)->frame + (fraim)->rsize, 4))
|
||
|
||
/* Local variables (i.e. LOC_LOCAL) are on the memory stack, with their
|
||
offsets being relative to the memory stack pointer (high C) or
|
||
saved_msp (gcc). */
|
||
|
||
#define FRAME_LOCALS_ADDRESS(fi) frame_locals_address (fi)
|
||
extern CORE_ADDR frame_locals_address ();
|
||
|
||
/* Return number of args passed to a frame.
|
||
Can return -1, meaning no way to tell. */
|
||
/* While we could go the effort of finding the tags word and getting
|
||
the argcount field from it,
|
||
(1) It only counts arguments in registers, i.e. the first 16 words
|
||
of arguments
|
||
(2) It gives the number of arguments the function was declared with
|
||
not how many it was called with (or some variation, like all 16
|
||
words for varadic functions). This makes argcount pretty much
|
||
redundant with -g info, even for varadic functions.
|
||
So don't bother. */
|
||
#define FRAME_NUM_ARGS(numargs, fi) ((numargs) = -1)
|
||
|
||
#define FRAME_ARGS_ADDRESS(fi) FRAME_LOCALS_ADDRESS (fi)
|
||
|
||
/* Return number of bytes at start of arglist that are not really args. */
|
||
|
||
#define FRAME_ARGS_SKIP 0
|
||
|
||
/* Provide our own get_saved_register. HAVE_REGISTER_WINDOWS is insufficient
|
||
because registers get renumbered on the 29k without getting saved. */
|
||
|
||
#define GET_SAVED_REGISTER
|
||
|
||
/* Call function stuff. */
|
||
|
||
/* The dummy frame looks like this (see also the general frame picture
|
||
above):
|
||
|
||
register stack
|
||
|
||
| | frame for function
|
||
| locals_sproc | executing at time
|
||
|________________| of call_function.
|
||
| | We must not disturb
|
||
| args_out_sproc | it.
|
||
memory stack |________________|
|
||
|____lr1_sproc___|
|
||
| | |__retaddr_sproc_| <- gr1 (at start)
|
||
|____________|<-msp 0 <-----------mfp_dummy_____|
|
||
| | (at start) | |
|
||
| arg_slop | | saved regs |
|
||
| (16 words) | | gr96-gr124 |
|
||
|____________|<-msp 1--after | sr128-sr135 |
|
||
| | PUSH_DUMMY_FRAME| |
|
||
| struct ret | |________________|
|
||
| 17+ | | |
|
||
|____________|<- lrp | args_out_dummy |
|
||
| struct ret | | (16 words) |
|
||
| 16 | |________________|
|
||
| (16 words) | |____lr1_dummy___|
|
||
|____________|<- msp 2--after |_retaddr_dummy__|<- gr1 after
|
||
| | struct ret | | PUSH_DUMMY_FRAME
|
||
| margs17+ | area allocated | locals_inf |
|
||
| | |________________| called
|
||
|____________|<- msp 4--when | | function's
|
||
| | inf called | args_out_inf | frame (set up
|
||
| margs16 | |________________| by called
|
||
| (16 words) | |_____lr1_inf____| function).
|
||
|____________|<- msp 3--after | . |
|
||
| | args pushed | . |
|
||
| | | . |
|
||
| |
|
||
|
||
arg_slop: This area is so that when the call dummy adds 16 words to
|
||
the msp, it won't end up larger than mfp_dummy (it is needed in the
|
||
case where margs and struct_ret do not add up to at least 16 words).
|
||
struct ret: This area is allocated by GDB if the return value is more
|
||
than 16 words. struct ret_16 is not used on the 29k.
|
||
margs: Pushed by GDB. The call dummy copies the first 16 words to
|
||
args_out_dummy.
|
||
retaddr_sproc: Contains the PC at the time we call the function.
|
||
set by PUSH_DUMMY_FRAME and read by POP_FRAME.
|
||
retaddr_dummy: This points to a breakpoint instruction in the dummy. */
|
||
|
||
/* Rsize for dummy frame, in bytes. */
|
||
|
||
/* Bytes for outgoing args, lr1, and retaddr. */
|
||
#define DUMMY_ARG (2 * 4 + 16 * 4)
|
||
|
||
/* Number of special registers (sr128-) to save. */
|
||
#define DUMMY_SAVE_SR128 8
|
||
/* Number of general (gr96- or gr64-) registers to save. */
|
||
#define DUMMY_SAVE_GREGS 29
|
||
|
||
#define DUMMY_FRAME_RSIZE \
|
||
(4 /* mfp_dummy */ \
|
||
+ DUMMY_SAVE_GREGS * 4 \
|
||
+ DUMMY_SAVE_SR128 * 4 \
|
||
+ DUMMY_ARG \
|
||
)
|
||
|
||
/* Push an empty stack frame, to record the current PC, etc. */
|
||
|
||
#define PUSH_DUMMY_FRAME push_dummy_frame();
|
||
extern void push_dummy_frame ();
|
||
|
||
/* Discard from the stack the innermost frame,
|
||
restoring all saved registers. */
|
||
|
||
#define POP_FRAME pop_frame ();
|
||
extern void pop_frame ();
|
||
|
||
/* This sequence of words is the instructions
|
||
mtsrim cr, 15
|
||
loadm 0, 0, lr2, msp ; load first 16 words of arguments into registers
|
||
add msp, msp, 16 * 4 ; point to the remaining arguments
|
||
CONST_INSN:
|
||
const gr96,inf
|
||
consth gr96,inf
|
||
calli lr0, gr96
|
||
aseq 0x40,gr1,gr1 ; nop
|
||
asneq 0x50,gr1,gr1 ; breakpoint
|
||
*/
|
||
|
||
/* Position of the "const" instruction within CALL_DUMMY in bytes. */
|
||
#define CONST_INSN (3 * 4)
|
||
#if TARGET_BYTE_ORDER == HOST_BYTE_ORDER
|
||
#define CALL_DUMMY {0x0400870f, 0x3600827d, 0x157d7d40, 0x03ff60ff, \
|
||
0x02ff60ff, 0xc8008060, 0x70400101, 0x72500101}
|
||
#else /* Byte order differs. */
|
||
you lose
|
||
#endif /* Byte order differs. */
|
||
#define CALL_DUMMY_LENGTH (8 * 4)
|
||
|
||
#define CALL_DUMMY_START_OFFSET 0 /* Start execution at beginning of dummy */
|
||
|
||
/* Helper macro for FIX_CALL_DUMMY. WORDP is a long * which points to a
|
||
word in target byte order; bits 0-7 and 16-23 of *WORDP are replaced with
|
||
bits 0-7 and 8-15 of DATA (which is in host byte order). */
|
||
|
||
#if TARGET_BYTE_ORDER == BIG_ENDIAN
|
||
#define STUFF_I16(WORDP, DATA) \
|
||
{ \
|
||
*((char *)(WORDP) + 3) = ((DATA) & 0xff);\
|
||
*((char *)(WORDP) + 1) = (((DATA) >> 8) & 0xff);\
|
||
}
|
||
#else /* Target is little endian. */
|
||
#define STUFF_I16(WORDP, DATA) \
|
||
{
|
||
*(char *)(WORDP) = ((DATA) & 0xff);
|
||
*((char *)(WORDP) + 2) = (((DATA) >> 8) & 0xff);
|
||
}
|
||
#endif /* Target is little endian. */
|
||
|
||
/* Insert the specified number of args and function address
|
||
into a call sequence of the above form stored at DUMMYNAME. */
|
||
|
||
/* Currently this stuffs in the address of the function that we are calling.
|
||
If different 29k systems use different breakpoint instructions, it
|
||
could also stuff BREAKPOINT in the right place (to avoid having to
|
||
duplicate CALL_DUMMY in each tm-*.h file). */
|
||
|
||
#define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p) \
|
||
{\
|
||
STUFF_I16((char *)dummyname + CONST_INSN, fun);\
|
||
STUFF_I16((char *)dummyname + CONST_INSN + 4, fun >> 16);\
|
||
}
|
||
|
||
/* 29k architecture has separate data & instruction memories -- wired to
|
||
different pins on the chip -- and can't execute the data memory.
|
||
Also, there should be space after text_end;
|
||
we won't get a SIGSEGV or scribble on data space. */
|
||
|
||
#define CALL_DUMMY_LOCATION AFTER_TEXT_END
|
||
|
||
/* Because of this, we need (as a kludge) to know the addresses of the
|
||
text section. */
|
||
|
||
#define NEED_TEXT_START_END
|
||
|
||
/* How to translate register numbers in the .stab's into gdb's internal register
|
||
numbers. We don't translate them, but we warn if an invalid register
|
||
number is seen. Note that FIXME, we use the value "sym" as an implicit
|
||
argument in printing the error message. It happens to be available where
|
||
this macro is used. (This macro definition appeared in a late revision
|
||
of gdb-3.91.6 and is not well tested. Also, it should be a "complaint".) */
|
||
|
||
#define STAB_REG_TO_REGNUM(num) \
|
||
(((num) > LR0_REGNUM + 127) \
|
||
? fprintf(stderr, \
|
||
"Invalid register number %d in symbol table entry for %s\n", \
|
||
(num), SYMBOL_NAME (sym)), (num) \
|
||
: (num))
|