xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/sparc-sol2-tdep.c (revision c38e7cc395b1472a774ff828e46123de44c628e9)
1 /* Target-dependent code for Solaris SPARC.
2 
3    Copyright (C) 2003-2016 Free Software Foundation, Inc.
4 
5    This file is part of GDB.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 #include "defs.h"
21 #include "frame.h"
22 #include "frame-unwind.h"
23 #include "gdbcore.h"
24 #include "symtab.h"
25 #include "objfiles.h"
26 #include "osabi.h"
27 #include "regcache.h"
28 #include "regset.h"
29 #include "target.h"
30 #include "trad-frame.h"
31 
32 #include "sol2-tdep.h"
33 #include "sparc-tdep.h"
34 #include "solib-svr4.h"
35 
36 /* From <sys/regset.h>.  */
37 const struct sparc_gregmap sparc32_sol2_gregmap =
38 {
39   32 * 4,			/* %psr */
40   33 * 4,			/* %pc */
41   34 * 4,			/* %npc */
42   35 * 4,			/* %y */
43   36 * 4,			/* %wim */
44   37 * 4,			/* %tbr */
45   1 * 4,			/* %g1 */
46   16 * 4,			/* %l0 */
47 };
48 
49 const struct sparc_fpregmap sparc32_sol2_fpregmap =
50 {
51   0 * 4,			/* %f0 */
52   33 * 4,			/* %fsr */
53 };
54 
55 static void
56 sparc32_sol2_supply_core_gregset (const struct regset *regset,
57 				  struct regcache *regcache,
58 				  int regnum, const void *gregs, size_t len)
59 {
60   sparc32_supply_gregset (&sparc32_sol2_gregmap, regcache, regnum, gregs);
61 }
62 
63 static void
64 sparc32_sol2_collect_core_gregset (const struct regset *regset,
65 				   const struct regcache *regcache,
66 				   int regnum, void *gregs, size_t len)
67 {
68   sparc32_collect_gregset (&sparc32_sol2_gregmap, regcache, regnum, gregs);
69 }
70 
71 static void
72 sparc32_sol2_supply_core_fpregset (const struct regset *regset,
73 				   struct regcache *regcache,
74 				   int regnum, const void *fpregs, size_t len)
75 {
76   sparc32_supply_fpregset (&sparc32_sol2_fpregmap, regcache, regnum, fpregs);
77 }
78 
79 static void
80 sparc32_sol2_collect_core_fpregset (const struct regset *regset,
81 				    const struct regcache *regcache,
82 				    int regnum, void *fpregs, size_t len)
83 {
84   sparc32_collect_fpregset (&sparc32_sol2_fpregmap, regcache, regnum, fpregs);
85 }
86 
87 static const struct regset sparc32_sol2_gregset =
88   {
89     NULL,
90     sparc32_sol2_supply_core_gregset,
91     sparc32_sol2_collect_core_gregset
92   };
93 
94 static const struct regset sparc32_sol2_fpregset =
95   {
96     NULL,
97     sparc32_sol2_supply_core_fpregset,
98     sparc32_sol2_collect_core_fpregset
99   };
100 
101 
102 /* The Solaris signal trampolines reside in libc.  For normal signals,
103    the function `sigacthandler' is used.  This signal trampoline will
104    call the signal handler using the System V calling convention,
105    where the third argument is a pointer to an instance of
106    `ucontext_t', which has a member `uc_mcontext' that contains the
107    saved registers.  Incidentally, the kernel passes the `ucontext_t'
108    pointer as the third argument of the signal trampoline too, and
109    `sigacthandler' simply passes it on.  However, if you link your
110    program with "-L/usr/ucblib -R/usr/ucblib -lucb", the function
111    `ucbsigvechandler' will be used, which invokes the using the BSD
112    convention, where the third argument is a pointer to an instance of
113    `struct sigcontext'.  It is the `ucbsigvechandler' function that
114    converts the `ucontext_t' to a `sigcontext', and back.  Unless the
115    signal handler modifies the `struct sigcontext' we can safely
116    ignore this.  */
117 
118 int
119 sparc_sol2_pc_in_sigtramp (CORE_ADDR pc, const char *name)
120 {
121   return (name && (strcmp (name, "sigacthandler") == 0
122 		   || strcmp (name, "ucbsigvechandler") == 0
123 		   || strcmp (name, "__sighndlr") == 0));
124 }
125 
126 static struct sparc_frame_cache *
127 sparc32_sol2_sigtramp_frame_cache (struct frame_info *this_frame,
128 				   void **this_cache)
129 {
130   struct sparc_frame_cache *cache;
131   CORE_ADDR mcontext_addr, addr;
132   int regnum;
133 
134   if (*this_cache)
135     return (struct sparc_frame_cache *) *this_cache;
136 
137   cache = sparc_frame_cache (this_frame, this_cache);
138   gdb_assert (cache == *this_cache);
139 
140   cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
141 
142   /* The third argument is a pointer to an instance of `ucontext_t',
143      which has a member `uc_mcontext' that contains the saved
144      registers.  */
145   regnum =
146     (cache->copied_regs_mask & 0x04) ? SPARC_I2_REGNUM : SPARC_O2_REGNUM;
147   mcontext_addr = get_frame_register_unsigned (this_frame, regnum) + 40;
148 
149   cache->saved_regs[SPARC32_PSR_REGNUM].addr = mcontext_addr + 0 * 4;
150   cache->saved_regs[SPARC32_PC_REGNUM].addr = mcontext_addr + 1 * 4;
151   cache->saved_regs[SPARC32_NPC_REGNUM].addr = mcontext_addr + 2 * 4;
152   cache->saved_regs[SPARC32_Y_REGNUM].addr = mcontext_addr + 3 * 4;
153 
154   /* Since %g0 is always zero, keep the identity encoding.  */
155   for (regnum = SPARC_G1_REGNUM, addr = mcontext_addr + 4 * 4;
156        regnum <= SPARC_O7_REGNUM; regnum++, addr += 4)
157     cache->saved_regs[regnum].addr = addr;
158 
159   if (get_frame_memory_unsigned (this_frame, mcontext_addr + 19 * 4, 4))
160     {
161       /* The register windows haven't been flushed.  */
162       for (regnum = SPARC_L0_REGNUM; regnum <= SPARC_I7_REGNUM; regnum++)
163 	trad_frame_set_unknown (cache->saved_regs, regnum);
164     }
165   else
166     {
167       addr = cache->saved_regs[SPARC_SP_REGNUM].addr;
168       addr = get_frame_memory_unsigned (this_frame, addr, 4);
169       for (regnum = SPARC_L0_REGNUM;
170 	   regnum <= SPARC_I7_REGNUM; regnum++, addr += 4)
171 	cache->saved_regs[regnum].addr = addr;
172     }
173 
174   return cache;
175 }
176 
177 static void
178 sparc32_sol2_sigtramp_frame_this_id (struct frame_info *this_frame,
179 				     void **this_cache,
180 				     struct frame_id *this_id)
181 {
182   struct sparc_frame_cache *cache =
183     sparc32_sol2_sigtramp_frame_cache (this_frame, this_cache);
184 
185   (*this_id) = frame_id_build (cache->base, cache->pc);
186 }
187 
188 static struct value *
189 sparc32_sol2_sigtramp_frame_prev_register (struct frame_info *this_frame,
190 					   void **this_cache,
191 					   int regnum)
192 {
193   struct sparc_frame_cache *cache =
194     sparc32_sol2_sigtramp_frame_cache (this_frame, this_cache);
195 
196   return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum);
197 }
198 
199 static int
200 sparc32_sol2_sigtramp_frame_sniffer (const struct frame_unwind *self,
201 				     struct frame_info *this_frame,
202 				     void **this_cache)
203 {
204   CORE_ADDR pc = get_frame_pc (this_frame);
205   const char *name;
206 
207   find_pc_partial_function (pc, &name, NULL, NULL);
208   if (sparc_sol2_pc_in_sigtramp (pc, name))
209     return 1;
210 
211   return 0;
212 }
213 
214 static const struct frame_unwind sparc32_sol2_sigtramp_frame_unwind =
215 {
216   SIGTRAMP_FRAME,
217   default_frame_unwind_stop_reason,
218   sparc32_sol2_sigtramp_frame_this_id,
219   sparc32_sol2_sigtramp_frame_prev_register,
220   NULL,
221   sparc32_sol2_sigtramp_frame_sniffer
222 };
223 
224 /* Unglobalize NAME.  */
225 
226 const char *
227 sparc_sol2_static_transform_name (const char *name)
228 {
229   /* The Sun compilers (Sun ONE Studio, Forte Developer, Sun WorkShop,
230      SunPRO) convert file static variables into global values, a
231      process known as globalization.  In order to do this, the
232      compiler will create a unique prefix and prepend it to each file
233      static variable.  For static variables within a function, this
234      globalization prefix is followed by the function name (nested
235      static variables within a function are supposed to generate a
236      warning message, and are left alone).  The procedure is
237      documented in the Stabs Interface Manual, which is distrubuted
238      with the compilers, although version 4.0 of the manual seems to
239      be incorrect in some places, at least for SPARC.  The
240      globalization prefix is encoded into an N_OPT stab, with the form
241      "G=<prefix>".  The globalization prefix always seems to start
242      with a dollar sign '$'; a dot '.' is used as a seperator.  So we
243      simply strip everything up until the last dot.  */
244 
245   if (name[0] == '$')
246     {
247       const char *p = strrchr (name, '.');
248       if (p)
249         return p + 1;
250     }
251 
252   return name;
253 }
254 
255 
256 void
257 sparc32_sol2_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
258 {
259   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
260 
261   tdep->gregset = &sparc32_sol2_gregset;
262   tdep->sizeof_gregset = 152;
263 
264   tdep->fpregset = &sparc32_sol2_fpregset;
265   tdep->sizeof_fpregset = 400;
266 
267   /* The Sun compilers (Sun ONE Studio, Forte Developer, Sun WorkShop, SunPRO)
268      compiler puts out 0 instead of the address in N_SO stabs.  Starting with
269      SunPRO 3.0, the compiler does this for N_FUN stabs too.  */
270   set_gdbarch_sofun_address_maybe_missing (gdbarch, 1);
271 
272   /* The Sun compilers also do "globalization"; see the comment in
273      sparc_sol2_static_transform_name for more information.  */
274   set_gdbarch_static_transform_name
275     (gdbarch, sparc_sol2_static_transform_name);
276 
277   /* Solaris has SVR4-style shared libraries...  */
278   set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
279   set_gdbarch_skip_solib_resolver (gdbarch, sol2_skip_solib_resolver);
280   set_solib_svr4_fetch_link_map_offsets
281     (gdbarch, svr4_ilp32_fetch_link_map_offsets);
282 
283   /* ...which means that we need some special handling when doing
284      prologue analysis.  */
285   tdep->plt_entry_size = 12;
286 
287   /* Solaris has kernel-assisted single-stepping support.  */
288   set_gdbarch_software_single_step (gdbarch, NULL);
289 
290   frame_unwind_append_unwinder (gdbarch, &sparc32_sol2_sigtramp_frame_unwind);
291 
292   /* How to print LWP PTIDs from core files.  */
293   set_gdbarch_core_pid_to_str (gdbarch, sol2_core_pid_to_str);
294 }
295 
296 
297 /* Provide a prototype to silence -Wmissing-prototypes.  */
298 void _initialize_sparc_sol2_tdep (void);
299 
300 void
301 _initialize_sparc_sol2_tdep (void)
302 {
303   gdbarch_register_osabi (bfd_arch_sparc, 0,
304 			  GDB_OSABI_SOLARIS, sparc32_sol2_init_abi);
305 }
306