xref: /openbsd/gnu/usr.bin/binutils/gdb/i386v4-nat.c (revision 09467b48)
1 /* Native-dependent code for Unix SVR4 running on i386's.
2 
3    Copyright 1988, 1989, 1991, 1992, 1996, 1997, 1998, 1999, 2000,
4    2001, 2002, 2004
5    Free Software Foundation, Inc.
6 
7    This file is part of GDB.
8 
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 2 of the License, or
12    (at your option) any later version.
13 
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18 
19    You should have received a copy of the GNU General Public License
20    along with this program; if not, write to the Free Software
21    Foundation, Inc., 59 Temple Place - Suite 330,
22    Boston, MA 02111-1307, USA.  */
23 
24 #include "defs.h"
25 #include "value.h"
26 #include "inferior.h"
27 #include "regcache.h"
28 
29 #ifdef HAVE_SYS_REG_H
30 #include <sys/reg.h>
31 #endif
32 
33 #include "i386-tdep.h"
34 #include "i387-tdep.h"
35 
36 #ifdef HAVE_SYS_PROCFS_H
37 
38 #include <sys/procfs.h>
39 
40 /* Prototypes for supply_gregset etc. */
41 #include "gregset.h"
42 
43 /* The `/proc' interface divides the target machine's register set up
44    into two different sets, the general purpose register set (gregset)
45    and the floating-point register set (fpregset).  For each set,
46    there is an ioctl to get the current register set and another ioctl
47    to set the current values.
48 
49    The actual structure passed through the ioctl interface is, of
50    course, naturally machine dependent, and is different for each set
51    of registers.  For the i386 for example, the general-purpose
52    register set is typically defined by:
53 
54    typedef int gregset_t[19];           (in <sys/regset.h>)
55 
56    #define GS   0                       (in <sys/reg.h>)
57    #define FS   1
58    ...
59    #define UESP 17
60    #define SS   18
61 
62    and the floating-point set by:
63 
64    typedef struct fpregset   {
65            union {
66                    struct fpchip_state            // fp extension state //
67                    {
68                            int     state[27];     // 287/387 saved state //
69                            int     status;        // status word saved at //
70                                                   // exception //
71                    } fpchip_state;
72                    struct fp_emul_space           // for emulators //
73                    {
74                            char    fp_emul[246];
75                            char    fp_epad[2];
76                    } fp_emul_space;
77                    int     f_fpregs[62];          // union of the above //
78            } fp_reg_set;
79            long            f_wregs[33];           // saved weitek state //
80    } fpregset_t;
81 
82    Incidentally fpchip_state contains the FPU state in the same format
83    as used by the "fsave" instruction, and that's the only thing we
84    support here.  I don't know how the emulator stores it state.  The
85    Weitek stuff definitely isn't supported.
86 
87    The routines defined here, provide the packing and unpacking of
88    gregset_t and fpregset_t formatted data.  */
89 
90 #ifdef HAVE_GREGSET_T
91 
92 /* Mapping between the general-purpose registers in `/proc'
93    format and GDB's register array layout.  */
94 static int regmap[] =
95 {
96   EAX, ECX, EDX, EBX,
97   UESP, EBP, ESI, EDI,
98   EIP, EFL, CS, SS,
99   DS, ES, FS, GS
100 };
101 
102 /* Fill GDB's register array with the general-purpose register values
103    in *GREGSETP.  */
104 
105 void
106 supply_gregset (gregset_t *gregsetp)
107 {
108   greg_t *regp = (greg_t *) gregsetp;
109   int regnum;
110 
111   for (regnum = 0; regnum < I386_NUM_GREGS; regnum++)
112     regcache_raw_supply (current_regcache, regnum, regp + regmap[regnum]);
113 }
114 
115 /* Fill register REGNUM (if it is a general-purpose register) in
116    *GREGSETPS with the value in GDB's register array.  If REGNUM is -1,
117    do this for all registers.  */
118 
119 void
120 fill_gregset (gregset_t *gregsetp, int regnum)
121 {
122   greg_t *regp = (greg_t *) gregsetp;
123   int i;
124 
125   for (i = 0; i < I386_NUM_GREGS; i++)
126     if (regnum == -1 || regnum == i)
127       regcache_raw_collect (current_regcache, i, regp + regmap[i]);
128 }
129 
130 #endif /* HAVE_GREGSET_T */
131 
132 #ifdef HAVE_FPREGSET_T
133 
134 /* Fill GDB's register array with the floating-point register values in
135    *FPREGSETP.  */
136 
137 void
138 supply_fpregset (fpregset_t *fpregsetp)
139 {
140   if (FP0_REGNUM == 0)
141     return;
142 
143   i387_supply_fsave (current_regcache, -1, fpregsetp);
144 }
145 
146 /* Fill register REGNO (if it is a floating-point register) in
147    *FPREGSETP with the value in GDB's register array.  If REGNO is -1,
148    do this for all registers.  */
149 
150 void
151 fill_fpregset (fpregset_t *fpregsetp, int regno)
152 {
153   if (FP0_REGNUM == 0)
154     return;
155 
156   i387_fill_fsave ((char *) fpregsetp, regno);
157 }
158 
159 #endif /* HAVE_FPREGSET_T */
160 
161 #endif /* HAVE_SYS_PROCFS_H */
162