diff options
Diffstat (limited to 'gdb/m68k-tdep.c')
| -rw-r--r-- | gdb/m68k-tdep.c | 327 |
1 files changed, 319 insertions, 8 deletions
diff --git a/gdb/m68k-tdep.c b/gdb/m68k-tdep.c index edb87db..2408718 100644 --- a/gdb/m68k-tdep.c +++ b/gdb/m68k-tdep.c @@ -3,24 +3,335 @@ This file is part of GDB. -GDB is free software; you can redistribute it and/or modify +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 1, or (at your option) -any later version. +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. -GDB is distributed in the hope that it will be useful, +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 GDB; see the file COPYING. If not, write to -the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ +along with this program; if not, write to the Free Software +Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "defs.h" #include "ieee-float.h" +#include "param.h" +#include "frame.h" +#include "symtab.h" -const struct ext_format ext_format_68881 [] = { +const struct ext_format ext_format_68881 = { /* tot sbyte smask expbyte manbyte */ - { 12, 0, 0x80, 0,1, 4,8 }, /* mc68881 */ + 12, 0, 0x80, 0,1, 4,8 /* mc68881 */ }; + + +/* Things needed for making the inferior call functions. + It seems like every m68k based machine has almost identical definitions + in the individual machine's configuration files. Most other cpu types + (mips, i386, etc) have routines in their *-tdep.c files to handle this + for most configurations. The m68k family should be able to do this as + well. These macros can still be overridden when necessary. */ + +/* Push an empty stack frame, to record the current PC, etc. */ + +void +m68k_push_dummy_frame () +{ + register CORE_ADDR sp = read_register (SP_REGNUM); + register int regnum; + char raw_buffer[12]; + + sp = push_word (sp, read_register (PC_REGNUM)); + sp = push_word (sp, read_register (FP_REGNUM)); + write_register (FP_REGNUM, sp); +#if defined (HAVE_68881) + for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--) + { + read_register_bytes (REGISTER_BYTE (regnum), raw_buffer, 12); + sp = push_bytes (sp, raw_buffer, 12); + } +#endif + for (regnum = FP_REGNUM - 1; regnum >= 0; regnum--) + { + sp = push_word (sp, read_register (regnum)); + } + sp = push_word (sp, read_register (PS_REGNUM)); + write_register (SP_REGNUM, sp); +} + +/* Discard from the stack the innermost frame, + restoring all saved registers. */ + +void +m68k_pop_frame () +{ + register FRAME frame = get_current_frame (); + register CORE_ADDR fp; + register int regnum; + struct frame_saved_regs fsr; + struct frame_info *fi; + char raw_buffer[12]; + + fi = get_frame_info (frame); + fp = fi -> frame; + get_frame_saved_regs (fi, &fsr); +#if defined (HAVE_68881) + for (regnum = FP0_REGNUM + 7 ; regnum >= FP0_REGNUM ; regnum--) + { + if (fsr.regs[regnum]) + { + read_memory (fsr.regs[regnum], raw_buffer, 12); + write_register_bytes (REGISTER_BYTE (regnum), raw_buffer, 12); + } + } +#endif + for (regnum = FP_REGNUM - 1 ; regnum >= 0 ; regnum--) + { + if (fsr.regs[regnum]) + { + write_register (regnum, read_memory_integer (fsr.regs[regnum], 4)); + } + } + if (fsr.regs[PS_REGNUM]) + { + write_register (PS_REGNUM, read_memory_integer (fsr.regs[PS_REGNUM], 4)); + } + write_register (FP_REGNUM, read_memory_integer (fp, 4)); + write_register (PC_REGNUM, read_memory_integer (fp + 4, 4)); + write_register (SP_REGNUM, fp + 8); + flush_cached_frames (); + set_current_frame (create_new_frame (read_register (FP_REGNUM), + read_pc ())); +} + + +/* Given an ip value corresponding to the start of a function, + return the ip of the first instruction after the function + prologue. This is the generic m68k support. Machines which + require something different can override the SKIP_PROLOGUE + macro to point elsewhere. + + Some instructions which typically may appear in a function + prologue include: + + A link instruction, word form: + + link.w %a6,&0 4e56 XXXX + + A link instruction, long form: + + link.l %fp,&F%1 480e XXXX XXXX + + A movm instruction to preserve integer regs: + + movm.l &M%1,(4,%sp) 48ef XXXX XXXX + + A fmovm instruction to preserve float regs: + + fmovm &FPM%1,(FPO%1,%sp) f237 XXXX XXXX XXXX XXXX + + Some profiling setup code (FIXME, not recognized yet): + + lea.l (.L3,%pc),%a1 43fb XXXX XXXX XXXX + bsr _mcount 61ff XXXX XXXX + + */ + +#define P_LINK_L 0x480e +#define P_LINK_W 0x4e56 +#define P_MOV_L 0x207c +#define P_JSR 0x4eb9 +#define P_BSR 0x61ff +#define P_LEA_L 0x43fb +#define P_MOVM_L 0x48ef +#define P_FMOVM 0xf237 + +CORE_ADDR +m68k_skip_prologue (ip) +CORE_ADDR ip; +{ + register CORE_ADDR limit; + struct symtab_and_line sal; + register int op; + + /* Find out if there is a known limit for the extent of the prologue. + If so, ensure we don't go past it. If not, assume "infinity". */ + + sal = find_pc_line (ip, 0); + limit = (sal.end) ? sal.end : (CORE_ADDR) ~0; + + while (ip < limit) + { + op = read_memory_integer (ip, 2); + op &= 0xFFFF; + + if (op == P_LINK_W) + { + ip += 4; /* Skip link.w */ + } + else if (op == P_LINK_L) + { + ip += 6; /* Skip link.l */ + } + else if (op == P_MOVM_L) + { + ip += 6; /* Skip movm.l */ + } + else if (op == P_FMOVM) + { + ip += 10; /* Skip fmovm */ + } + else + { + break; /* Found unknown code, bail out. */ + } + } + return (ip); +} + +#ifdef USE_PROC_FS /* Target dependent support for /proc */ + +#include <sys/procfs.h> + +/* The /proc interface divides the target machine's register set up into + two different sets, the general register set (gregset) and the floating + point register set (fpregset). For each set, there is an ioctl to get + the current register set and another ioctl to set the current values. + + The actual structure passed through the ioctl interface is, of course, + naturally machine dependent, and is different for each set of registers. + For the m68k for example, the general register set is typically defined + by: + + typedef int gregset_t[18]; + + #define R_D0 0 + ... + #define R_PS 17 + + and the floating point set by: + + typedef struct fpregset { + int f_pcr; + int f_psr; + int f_fpiaddr; + int f_fpregs[8][3]; (8 regs, 96 bits each) + } fpregset_t; + + These routines provide the packing and unpacking of gregset_t and + fpregset_t formatted data. + + */ + + +/* Given a pointer to a general register set in /proc format (gregset_t *), + unpack the register contents and supply them as gdb's idea of the current + register values. */ + +void +supply_gregset (gregsetp) +gregset_t *gregsetp; +{ + register int regno; + register greg_t *regp = (greg_t *) gregsetp; + + for (regno = 0 ; regno < R_PC ; regno++) + { + supply_register (regno, (char *) (regp + regno)); + } + supply_register (PS_REGNUM, (char *) (regp + R_PS)); + supply_register (PC_REGNUM, (char *) (regp + R_PC)); +} + +void +fill_gregset (gregsetp, regno) +gregset_t *gregsetp; +int regno; +{ + int regi; + register greg_t *regp = (greg_t *) gregsetp; + extern char registers[]; + + for (regi = 0 ; regi < R_PC ; regi++) + { + if ((regno == -1) || (regno == regi)) + { + *(regp + regno) = *(int *) ®isters[REGISTER_BYTE (regi)]; + } + } + if ((regno == -1) || (regno == PS_REGNUM)) + { + *(regp + R_PS) = *(int *) ®isters[REGISTER_BYTE (PS_REGNUM)]; + } + if ((regno == -1) || (regno == PC_REGNUM)) + { + *(regp + R_PC) = *(int *) ®isters[REGISTER_BYTE (PC_REGNUM)]; + } +} + +#if defined (FP0_REGNUM) + +/* Given a pointer to a floating point register set in /proc format + (fpregset_t *), unpack the register contents and supply them as gdb's + idea of the current floating point register values. */ + +void +supply_fpregset (fpregsetp) +fpregset_t *fpregsetp; +{ + register int regno; + + for (regno = FP0_REGNUM ; regno < FPC_REGNUM ; regno++) + { + supply_register (regno, (char *) &(fpregsetp -> f_fpregs[regno][0])); + } + supply_register (FPC_REGNUM, (char *) &(fpregsetp -> f_pcr)); + supply_register (FPS_REGNUM, (char *) &(fpregsetp -> f_psr)); + supply_register (FPI_REGNUM, (char *) &(fpregsetp -> f_fpiaddr)); +} + +/* Given a pointer to a floating point register set in /proc format + (fpregset_t *), update the register specified by REGNO from gdb's idea + of the current floating point register set. If REGNO is -1, update + them all. */ + +void +fill_fpregset (fpregsetp, regno) +fpregset_t *fpregsetp; +int regno; +{ + int regi; + char *to; + char *from; + extern char registers[]; + + for (regi = FP0_REGNUM ; regi < FPC_REGNUM ; regi++) + { + if ((regno == -1) || (regno == regi)) + { + from = (char *) ®isters[REGISTER_BYTE (regi)]; + to = (char *) &(fpregsetp -> f_fpregs[regi][0]); + bcopy (from, to, REGISTER_RAW_SIZE (regno)); + } + } + if ((regno == -1) || (regno == FPC_REGNUM)) + { + fpregsetp -> f_pcr = *(int *) ®isters[REGISTER_BYTE (FPC_REGNUM)]; + } + if ((regno == -1) || (regno == FPS_REGNUM)) + { + fpregsetp -> f_psr = *(int *) ®isters[REGISTER_BYTE (FPS_REGNUM)]; + } + if ((regno == -1) || (regno == FPI_REGNUM)) + { + fpregsetp -> f_fpiaddr = *(int *) ®isters[REGISTER_BYTE (FPI_REGNUM)]; + } +} + +#endif /* defined (FP0_REGNUM) */ + +#endif /* USE_PROC_FS */ |