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, Boston, MA 02111-1307, USA.  */
  19
  20 #include "defs.h"
  21 #include "inferior.h"
  22 #include "gdbcore.h"
  23 #include "target.h"
  24
  25 #include <sys/time.h>
  26 #include <sys/procfs.h>
  27 #include <setjmp.h>             /* For JB_XXX.  */
  28
  29 /* Size of elements in jmpbuf */
  30
  31 #define JB_ELEMENT_SIZE 4
  32
  33 /*
  34  * See the comment in m68k-tdep.c regarding the utility of these functions.
  35  *
  36  * These definitions are from the MIPS SVR4 ABI, so they may work for
  37  * any MIPS SVR4 target.
  38  */
  39
  40 void
  41 supply_gregset (gregsetp)
  42      gregset_t *gregsetp;
  43 {
  44   register int regi;
  45   register greg_t *regp = &(*gregsetp)[0];
  46   static char zerobuf[MAX_REGISTER_RAW_SIZE] = {0};
  47
  48   for (regi = 0; regi <= CXT_RA; regi++)
  49     supply_register (regi, (char *)(regp + regi));
  50
  51   supply_register (PC_REGNUM, (char *)(regp + CXT_EPC));
  52   supply_register (HI_REGNUM, (char *)(regp + CXT_MDHI));
  53   supply_register (LO_REGNUM, (char *)(regp + CXT_MDLO));
  54   supply_register (CAUSE_REGNUM, (char *)(regp + CXT_CAUSE));
  55
  56   /* Fill inaccessible registers with zero.  */
  57   supply_register (PS_REGNUM, zerobuf);
  58   supply_register (BADVADDR_REGNUM, zerobuf);
  59   supply_register (FP_REGNUM, zerobuf);
  60   supply_register (UNUSED_REGNUM, zerobuf);
  61   for (regi = FIRST_EMBED_REGNUM; regi <= LAST_EMBED_REGNUM; regi++)
  62     supply_register (regi, zerobuf);
  63 }
  64
  65 void
  66 fill_gregset (gregsetp, regno)
  67      gregset_t *gregsetp;
  68      int regno;
  69 {
  70   int regi;
  71   register greg_t *regp = &(*gregsetp)[0];
  72
  73   for (regi = 0; regi <= 32; regi++)
  74     if ((regno == -1) || (regno == regi))
  75       *(regp + regi) = *(greg_t *) &registers[REGISTER_BYTE (regi)];
  76
  77   if ((regno == -1) || (regno == PC_REGNUM))
  78     *(regp + CXT_EPC) = *(greg_t *) &registers[REGISTER_BYTE (PC_REGNUM)];
  79
  80   if ((regno == -1) || (regno == CAUSE_REGNUM))
  81     *(regp + CXT_CAUSE) = *(greg_t *) &registers[REGISTER_BYTE (CAUSE_REGNUM)];
  82
  83   if ((regno == -1) || (regno == HI_REGNUM))
  84     *(regp + CXT_MDHI) = *(greg_t *) &registers[REGISTER_BYTE (HI_REGNUM)];
  85
  86   if ((regno == -1) || (regno == LO_REGNUM))
  87     *(regp + CXT_MDLO) = *(greg_t *) &registers[REGISTER_BYTE (LO_REGNUM)];
  88 }
  89
  90 /*
  91  * Now we do the same thing for floating-point registers.
  92  * We don't bother to condition on FP0_REGNUM since any
  93  * reasonable MIPS configuration has an R3010 in it.
  94  *
  95  * Again, see the comments in m68k-tdep.c.
  96  */
  97
  98 void
  99 supply_fpregset (fpregsetp)
 100      fpregset_t *fpregsetp;
 101 {
 102   register int regi;
 103   static char zerobuf[MAX_REGISTER_RAW_SIZE] = {0};
 104
 105   for (regi = 0; regi < 32; regi++)
 106     supply_register (FP0_REGNUM + regi,
 107                      (char *)&fpregsetp->fp_r.fp_regs[regi]);
 108
 109   supply_register (FCRCS_REGNUM, (char *)&fpregsetp->fp_csr);
 110
 111   /* FIXME: how can we supply FCRIR_REGNUM?  The ABI doesn't tell us. */
 112   supply_register (FCRIR_REGNUM, zerobuf);
 113 }
 114
 115 void
 116 fill_fpregset (fpregsetp, regno)
 117      fpregset_t *fpregsetp;
 118      int regno;
 119 {
 120   int regi;
 121   char *from, *to;
 122
 123   for (regi = FP0_REGNUM; regi < FP0_REGNUM + 32; regi++)
 124     {
 125       if ((regno == -1) || (regno == regi))
 126         {
 127           from = (char *) &registers[REGISTER_BYTE (regi)];
 128           to = (char *) &(fpregsetp->fp_r.fp_regs[regi - FP0_REGNUM]);
 129           memcpy(to, from, REGISTER_RAW_SIZE (regi));
 130         }
 131     }
 132
 133   if ((regno == -1) || (regno == FCRCS_REGNUM))
 134     fpregsetp->fp_csr = *(unsigned *) &registers[REGISTER_BYTE(FCRCS_REGNUM)];
 135 }
 136
 137
 138 /* Figure out where the longjmp will land.
 139    We expect the first arg to be a pointer to the jmp_buf structure from which
 140    we extract the pc (_JB_PC) that we will land at.  The pc is copied into PC.
 141    This routine returns true on success. */
 142
 143 int
 144 get_longjmp_target (pc)
 145      CORE_ADDR *pc;
 146 {
 147   char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
 148   CORE_ADDR jb_addr;
 149
 150   jb_addr = read_register (A0_REGNUM);
 151
 152   if (target_read_memory (jb_addr + _JB_PC * JB_ELEMENT_SIZE, buf,
 153                           TARGET_PTR_BIT / TARGET_CHAR_BIT))
 154     return 0;
 155
 156   *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
 157
 158   return 1;
 159 }