xref: /openbsd-src/gnu/usr.bin/binutils/gdb/mipsv4-nat.c (revision 63addd46c1e40ca0f49488ddcdc4ab598023b0c1)
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
supply_gregset(gregset_t * gregsetp)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, 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, UNUSED_REGNUM, zerobuf);
72   for (regi = FIRST_EMBED_REGNUM; regi <= LAST_EMBED_REGNUM; regi++)
73     regcache_raw_supply (current_regcache, regi, zerobuf);
74 }
75 
76 void
fill_gregset(gregset_t * gregsetp,int regno)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
supply_fpregset(fpregset_t * fpregsetp)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
fill_fpregset(fpregset_t * fpregsetp,int regno)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
get_longjmp_target(CORE_ADDR * pc)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 (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 }
174