gdb/mipsv4-nat.c

   1 /* Native support for MIPS running SVR4, for GDB.
   2    Copyright 1994, 1995 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include "inferior.h"
  23 #include "gdbcore.h"
  24 #include "target.h"
  25
  26 #include <sys/time.h>
  27 #include <sys/procfs.h>
  28 #include <setjmp.h>             /* For JB_XXX.  */
  29
  30 /* Prototypes for supply_gregset etc. */
  31 #include "gregset.h"
  32
  33 /* Size of elements in jmpbuf */
  34
  35 #define JB_ELEMENT_SIZE 4
  36
  37 /*
  38  * See the comment in m68k-tdep.c regarding the utility of these functions.
  39  *
  40  * These definitions are from the MIPS SVR4 ABI, so they may work for
  41  * any MIPS SVR4 target.
  42  */
  43
  44 void
  45 supply_gregset (gregsetp)
  46      gregset_t *gregsetp;
  47 {
  48   register int regi;
  49   register greg_t *regp = &(*gregsetp)[0];
  50   static char zerobuf[MAX_REGISTER_RAW_SIZE] =
  51   {0};
  52
  53   for (regi = 0; regi <= CXT_RA; regi++)
  54     supply_register (regi, (char *) (regp + regi));
  55
  56   supply_register (PC_REGNUM, (char *) (regp + CXT_EPC));
  57   supply_register (HI_REGNUM, (char *) (regp + CXT_MDHI));
  58   supply_register (LO_REGNUM, (char *) (regp + CXT_MDLO));
  59   supply_register (CAUSE_REGNUM, (char *) (regp + CXT_CAUSE));
  60
  61   /* Fill inaccessible registers with zero.  */
  62   supply_register (PS_REGNUM, zerobuf);
  63   supply_register (BADVADDR_REGNUM, zerobuf);
  64   supply_register (FP_REGNUM, zerobuf);
  65   supply_register (UNUSED_REGNUM, zerobuf);
  66   for (regi = FIRST_EMBED_REGNUM; regi <= LAST_EMBED_REGNUM; regi++)
  67     supply_register (regi, zerobuf);
  68 }
  69
  70 void
  71 fill_gregset (gregsetp, regno)
  72      gregset_t *gregsetp;
  73      int regno;
  74 {
  75   int regi;
  76   register greg_t *regp = &(*gregsetp)[0];
  77
  78   for (regi = 0; regi <= 32; regi++)
  79     if ((regno == -1) || (regno == regi))
  80       *(regp + regi) = *(greg_t *) & registers[REGISTER_BYTE (regi)];
  81
  82   if ((regno == -1) || (regno == PC_REGNUM))
  83     *(regp + CXT_EPC) = *(greg_t *) & registers[REGISTER_BYTE (PC_REGNUM)];
  84
  85   if ((regno == -1) || (regno == CAUSE_REGNUM))
  86     *(regp + CXT_CAUSE) = *(greg_t *) & registers[REGISTER_BYTE (CAUSE_REGNUM)];
  87
  88   if ((regno == -1) || (regno == HI_REGNUM))
  89     *(regp + CXT_MDHI) = *(greg_t *) & registers[REGISTER_BYTE (HI_REGNUM)];
  90
  91   if ((regno == -1) || (regno == LO_REGNUM))
  92     *(regp + CXT_MDLO) = *(greg_t *) & registers[REGISTER_BYTE (LO_REGNUM)];
  93 }
  94
  95 /*
  96  * Now we do the same thing for floating-point registers.
  97  * We don't bother to condition on FP0_REGNUM since any
  98  * reasonable MIPS configuration has an R3010 in it.
  99  *
 100  * Again, see the comments in m68k-tdep.c.
 101  */
 102
 103 void
 104 supply_fpregset (fpregsetp)
 105      fpregset_t *fpregsetp;
 106 {
 107   register int regi;
 108   static char zerobuf[MAX_REGISTER_RAW_SIZE] =
 109   {0};
 110
 111   for (regi = 0; regi < 32; regi++)
 112     supply_register (FP0_REGNUM + regi,
 113                      (char *) &fpregsetp->fp_r.fp_regs[regi]);
 114
 115   supply_register (FCRCS_REGNUM, (char *) &fpregsetp->fp_csr);
 116
 117   /* FIXME: how can we supply FCRIR_REGNUM?  The ABI doesn't tell us. */
 118   supply_register (FCRIR_REGNUM, zerobuf);
 119 }
 120
 121 void
 122 fill_fpregset (fpregsetp, regno)
 123      fpregset_t *fpregsetp;
 124      int regno;
 125 {
 126   int regi;
 127   char *from, *to;
 128
 129   for (regi = FP0_REGNUM; regi < FP0_REGNUM + 32; regi++)
 130     {
 131       if ((regno == -1) || (regno == regi))
 132         {
 133           from = (char *) &registers[REGISTER_BYTE (regi)];
 134           to = (char *) &(fpregsetp->fp_r.fp_regs[regi - FP0_REGNUM]);
 135           memcpy (to, from, REGISTER_RAW_SIZE (regi));
 136         }
 137     }
 138
 139   if ((regno == -1) || (regno == FCRCS_REGNUM))
 140     fpregsetp->fp_csr = *(unsigned *) &registers[REGISTER_BYTE (FCRCS_REGNUM)];
 141 }
 142
 143
 144 /* Figure out where the longjmp will land.
 145    We expect the first arg to be a pointer to the jmp_buf structure from which
 146    we extract the pc (_JB_PC) that we will land at.  The pc is copied into PC.
 147    This routine returns true on success. */
 148
 149 int
 150 get_longjmp_target (pc)
 151      CORE_ADDR *pc;
 152 {
 153   char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
 154   CORE_ADDR jb_addr;
 155
 156   jb_addr = read_register (A0_REGNUM);
 157
 158   if (target_read_memory (jb_addr + _JB_PC * JB_ELEMENT_SIZE, buf,
 159                           TARGET_PTR_BIT / TARGET_CHAR_BIT))
 160     return 0;
 161
 162   *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
 163
 164   return 1;
 165 }