gdb/mipsv4-nat.c

   1 /* Native support for MIPS running SVR4, for GDB.
   2    Copyright 1994, 1995, 2000, 2001 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 #include "regcache.h"
  26
  27 #include <sys/time.h>
  28 #include <sys/procfs.h>
  29 #include <setjmp.h>             /* For JB_XXX.  */
  30
  31 /* Prototypes for supply_gregset etc. */
  32 #include "gregset.h"
  33
  34 /* Size of elements in jmpbuf */
  35
  36 #define JB_ELEMENT_SIZE 4
  37
  38 /*
  39  * See the comment in m68k-tdep.c regarding the utility of these functions.
  40  *
  41  * These definitions are from the MIPS SVR4 ABI, so they may work for
  42  * any MIPS SVR4 target.
  43  */
  44
  45 void
  46 supply_gregset (gregset_t *gregsetp)
  47 {
  48   int regi;
  49   greg_t *regp = &(*gregsetp)[0];
  50   char zerobuf[MAX_REGISTER_SIZE];
  51   memset (zerobuf, 0, MAX_REGISTER_SIZE);
  52
  53   for (regi = 0; regi <= CXT_RA; regi++)
  54     regcache_raw_supply (current_regcache, regi, (char *) (regp + regi));
  55
  56   regcache_raw_supply (current_regcache, mips_regnum (current_gdbarch)->pc,
  57                        (char *) (regp + CXT_EPC));
  58   regcache_raw_supply (current_regcache, mips_regnum (current_gdbarch)->hi,
  59                        (char *) (regp + CXT_MDHI));
  60   regcache_raw_supply (current_regcache, mips_regnum (current_gdbarch)->lo,
  61                        (char *) (regp + CXT_MDLO));
  62   regcache_raw_supply (current_regcache, mips_regnum (current_gdbarch)->cause,
  63                        (char *) (regp + CXT_CAUSE));
  64
  65   /* Fill inaccessible registers with zero.  */
  66   regcache_raw_supply (current_regcache, MIPS_PS_REGNUM, zerobuf);
  67   regcache_raw_supply (current_regcache,
  68                        mips_regnum (current_gdbarch)->badvaddr,
  69                        zerobuf);
  70   regcache_raw_supply (current_regcache, DEPRECATED_FP_REGNUM, zerobuf);
  71   regcache_raw_supply (current_regcache, MIPS_UNUSED_REGNUM, zerobuf);
  72   for (regi = MIPS_FIRST_EMBED_REGNUM; regi <= MIPS_LAST_EMBED_REGNUM; regi++)
  73     regcache_raw_supply (current_regcache, regi, zerobuf);
  74 }
  75
  76 void
  77 fill_gregset (gregset_t *gregsetp, int regno)
  78 {
  79   int regi;
  80   greg_t *regp = &(*gregsetp)[0];
  81
  82   for (regi = 0; regi <= 32; regi++)
  83     if ((regno == -1) || (regno == regi))
  84       *(regp + regi) = *(greg_t *) & deprecated_registers[DEPRECATED_REGISTER_BYTE (regi)];
  85
  86   if ((regno == -1) || (regno == mips_regnum (current_gdbarch)->pc))
  87     *(regp + CXT_EPC) = *(greg_t *) & deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->pc)];
  88
  89   if ((regno == -1) || (regno == mips_regnum (current_gdbarch)->cause))
  90     *(regp + CXT_CAUSE) = *(greg_t *) & deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->cause)];
  91
  92   if ((regno == -1) || (regno == mips_regnum (current_gdbarch)->hi))
  93     *(regp + CXT_MDHI) = *(greg_t *) & deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->hi)];
  94
  95   if ((regno == -1) || (regno == mips_regnum (current_gdbarch)->lo))
  96     *(regp + CXT_MDLO) = *(greg_t *) & deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->lo)];
  97 }
  98
  99 /*
 100  * Now we do the same thing for floating-point registers.
 101  * We don't bother to condition on FP0 regnum since any
 102  * reasonable MIPS configuration has an R3010 in it.
 103  *
 104  * Again, see the comments in m68k-tdep.c.
 105  */
 106
 107 void
 108 supply_fpregset (fpregset_t *fpregsetp)
 109 {
 110   int regi;
 111   char zerobuf[MAX_REGISTER_SIZE];
 112   memset (zerobuf, 0, MAX_REGISTER_SIZE);
 113
 114   for (regi = 0; regi < 32; regi++)
 115     regcache_raw_supply (current_regcache,
 116                          mips_regnum (current_gdbarch)->fp0 + regi,
 117                          (char *) &fpregsetp->fp_r.fp_regs[regi]);
 118
 119   regcache_raw_supply (current_regcache,
 120                        mips_regnum (current_gdbarch)->fp_control_status,
 121                        (char *) &fpregsetp->fp_csr);
 122
 123   /* FIXME: how can we supply FCRIR?  The ABI doesn't tell us. */
 124   regcache_raw_supply (current_regcache,
 125                        mips_regnum (current_gdbarch)->fp_implementation_revision,
 126                        zerobuf);
 127 }
 128
 129 void
 130 fill_fpregset (fpregset_t *fpregsetp, int regno)
 131 {
 132   int regi;
 133   char *from, *to;
 134
 135   for (regi = mips_regnum (current_gdbarch)->fp0;
 136        regi < mips_regnum (current_gdbarch)->fp0 + 32; regi++)
 137     {
 138       if ((regno == -1) || (regno == regi))
 139         {
 140           from = (char *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (regi)];
 141           to = (char *) &(fpregsetp->fp_r.fp_regs[regi - mips_regnum (current_gdbarch)->fp0]);
 142           memcpy (to, from, register_size (current_gdbarch, regi));
 143         }
 144     }
 145
 146   if ((regno == -1)
 147       || (regno == mips_regnum (current_gdbarch)->fp_control_status))
 148     fpregsetp->fp_csr = *(unsigned *) &deprecated_registers[DEPRECATED_REGISTER_BYTE (mips_regnum (current_gdbarch)->fp_control_status)];
 149 }
 150
 151
 152 /* Figure out where the longjmp will land.
 153    We expect the first arg to be a pointer to the jmp_buf structure from which
 154    we extract the pc (_JB_PC) that we will land at.  The pc is copied into PC.
 155    This routine returns true on success. */
 156
 157 int
 158 get_longjmp_target (CORE_ADDR *pc)
 159 {
 160   char *buf;
 161   CORE_ADDR jb_addr;
 162
 163   buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT);
 164   jb_addr = read_register (MIPS_A0_REGNUM);
 165
 166   if (target_read_memory (jb_addr + _JB_PC * JB_ELEMENT_SIZE, buf,
 167                           TARGET_PTR_BIT / TARGET_CHAR_BIT))
 168     return 0;
 169
 170   *pc = extract_unsigned_integer (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
 171
 172   return 1;
 173 }