1 /* Target-dependent code for GNU/Linux on Alpha.
2 Copyright (C) 2002-2014 Free Software Foundation, Inc.
4 This file is part of GDB.
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 3 of the License, or
9 (at your option) any later version.
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.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "solib-svr4.h"
26 #include "linux-tdep.h"
27 #include "alpha-tdep.h"
29 /* This enum represents the signals' numbers on the Alpha
30 architecture. It just contains the signal definitions which are
31 different from the generic implementation.
33 It is derived from the file <arch/alpha/include/uapi/asm/signal.h>,
34 from the Linux kernel tree. */
38 /* SIGABRT is the same as in the generic implementation, but is
39 defined here because SIGIOT depends on it. */
40 ALPHA_LINUX_SIGABRT = 6,
41 ALPHA_LINUX_SIGEMT = 7,
42 ALPHA_LINUX_SIGBUS = 10,
43 ALPHA_LINUX_SIGSYS = 12,
44 ALPHA_LINUX_SIGURG = 16,
45 ALPHA_LINUX_SIGSTOP = 17,
46 ALPHA_LINUX_SIGTSTP = 18,
47 ALPHA_LINUX_SIGCONT = 19,
48 ALPHA_LINUX_SIGCHLD = 20,
49 ALPHA_LINUX_SIGIO = 23,
50 ALPHA_LINUX_SIGINFO = 29,
51 ALPHA_LINUX_SIGUSR1 = 30,
52 ALPHA_LINUX_SIGUSR2 = 31,
53 ALPHA_LINUX_SIGPOLL = ALPHA_LINUX_SIGIO,
54 ALPHA_LINUX_SIGPWR = ALPHA_LINUX_SIGINFO,
55 ALPHA_LINUX_SIGIOT = ALPHA_LINUX_SIGABRT,
58 /* Under GNU/Linux, signal handler invocations can be identified by
59 the designated code sequence that is used to return from a signal
60 handler. In particular, the return address of a signal handler
61 points to a sequence that copies $sp to $16, loads $0 with the
62 appropriate syscall number, and finally enters the kernel.
64 This is somewhat complicated in that:
65 (1) the expansion of the "mov" assembler macro has changed over
66 time, from "bis src,src,dst" to "bis zero,src,dst",
67 (2) the kernel has changed from using "addq" to "lda" to load the
69 (3) there is a "normal" sigreturn and an "rt" sigreturn which
70 has a different stack layout. */
73 alpha_linux_sigtramp_offset_1 (struct gdbarch *gdbarch, CORE_ADDR pc)
75 switch (alpha_read_insn (gdbarch, pc))
77 case 0x47de0410: /* bis $30,$30,$16 */
78 case 0x47fe0410: /* bis $31,$30,$16 */
81 case 0x43ecf400: /* addq $31,103,$0 */
82 case 0x201f0067: /* lda $0,103($31) */
83 case 0x201f015f: /* lda $0,351($31) */
86 case 0x00000083: /* call_pal callsys */
95 alpha_linux_sigtramp_offset (struct gdbarch *gdbarch, CORE_ADDR pc)
102 /* Guess where we might be in the sequence. */
103 off = alpha_linux_sigtramp_offset_1 (gdbarch, pc);
107 /* Verify that the other two insns of the sequence are as we expect. */
109 for (i = 0; i < 12; i += 4)
113 if (alpha_linux_sigtramp_offset_1 (gdbarch, pc + i) != i)
121 alpha_linux_pc_in_sigtramp (struct gdbarch *gdbarch,
122 CORE_ADDR pc, const char *func_name)
124 return alpha_linux_sigtramp_offset (gdbarch, pc) >= 0;
128 alpha_linux_sigcontext_addr (struct frame_info *this_frame)
130 struct gdbarch *gdbarch = get_frame_arch (this_frame);
135 pc = get_frame_pc (this_frame);
136 sp = get_frame_register_unsigned (this_frame, ALPHA_SP_REGNUM);
138 off = alpha_linux_sigtramp_offset (gdbarch, pc);
139 gdb_assert (off >= 0);
141 /* __NR_rt_sigreturn has a couple of structures on the stack. This is:
148 offsetof (struct rt_sigframe, uc.uc_mcontext); */
150 if (alpha_read_insn (gdbarch, pc - off + 4) == 0x201f015f)
153 /* __NR_sigreturn has the sigcontext structure at the top of the stack. */
157 /* Supply register REGNUM from the buffer specified by GREGS and LEN
158 in the general-purpose register set REGSET to register cache
159 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
162 alpha_linux_supply_gregset (const struct regset *regset,
163 struct regcache *regcache,
164 int regnum, const void *gregs, size_t len)
166 const gdb_byte *regs = gregs;
168 gdb_assert (len >= 32 * 8);
170 for (i = 0; i < ALPHA_ZERO_REGNUM; i++)
172 if (regnum == i || regnum == -1)
173 regcache_raw_supply (regcache, i, regs + i * 8);
176 if (regnum == ALPHA_PC_REGNUM || regnum == -1)
177 regcache_raw_supply (regcache, ALPHA_PC_REGNUM, regs + 31 * 8);
179 if (regnum == ALPHA_UNIQUE_REGNUM || regnum == -1)
180 regcache_raw_supply (regcache, ALPHA_UNIQUE_REGNUM,
181 len >= 33 * 8 ? regs + 32 * 8 : NULL);
184 /* Supply register REGNUM from the buffer specified by FPREGS and LEN
185 in the floating-point register set REGSET to register cache
186 REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
189 alpha_linux_supply_fpregset (const struct regset *regset,
190 struct regcache *regcache,
191 int regnum, const void *fpregs, size_t len)
193 const gdb_byte *regs = fpregs;
195 gdb_assert (len >= 32 * 8);
197 for (i = ALPHA_FP0_REGNUM; i < ALPHA_FP0_REGNUM + 31; i++)
199 if (regnum == i || regnum == -1)
200 regcache_raw_supply (regcache, i, regs + (i - ALPHA_FP0_REGNUM) * 8);
203 if (regnum == ALPHA_FPCR_REGNUM || regnum == -1)
204 regcache_raw_supply (regcache, ALPHA_FPCR_REGNUM, regs + 31 * 8);
207 static const struct regset alpha_linux_gregset =
210 alpha_linux_supply_gregset
213 static const struct regset alpha_linux_fpregset =
216 alpha_linux_supply_fpregset
219 /* Return the appropriate register set for the core section identified
220 by SECT_NAME and SECT_SIZE. */
222 static const struct regset *
223 alpha_linux_regset_from_core_section (struct gdbarch *gdbarch,
224 const char *sect_name, size_t sect_size)
226 if (strcmp (sect_name, ".reg") == 0 && sect_size >= 32 * 8)
227 return &alpha_linux_gregset;
229 if (strcmp (sect_name, ".reg2") == 0 && sect_size >= 32 * 8)
230 return &alpha_linux_fpregset;
235 /* Implementation of `gdbarch_gdb_signal_from_target', as defined in
238 static enum gdb_signal
239 alpha_linux_gdb_signal_from_target (struct gdbarch *gdbarch,
244 case ALPHA_LINUX_SIGEMT:
245 return GDB_SIGNAL_EMT;
247 case ALPHA_LINUX_SIGBUS:
248 return GDB_SIGNAL_BUS;
250 case ALPHA_LINUX_SIGSYS:
251 return GDB_SIGNAL_SYS;
253 case ALPHA_LINUX_SIGURG:
254 return GDB_SIGNAL_URG;
256 case ALPHA_LINUX_SIGSTOP:
257 return GDB_SIGNAL_STOP;
259 case ALPHA_LINUX_SIGTSTP:
260 return GDB_SIGNAL_TSTP;
262 case ALPHA_LINUX_SIGCONT:
263 return GDB_SIGNAL_CONT;
265 case ALPHA_LINUX_SIGCHLD:
266 return GDB_SIGNAL_CHLD;
268 /* No way to differentiate between SIGIO and SIGPOLL.
269 Therefore, we just handle the first one. */
270 case ALPHA_LINUX_SIGIO:
271 return GDB_SIGNAL_IO;
273 /* No way to differentiate between SIGINFO and SIGPWR.
274 Therefore, we just handle the first one. */
275 case ALPHA_LINUX_SIGINFO:
276 return GDB_SIGNAL_INFO;
278 case ALPHA_LINUX_SIGUSR1:
279 return GDB_SIGNAL_USR1;
281 case ALPHA_LINUX_SIGUSR2:
282 return GDB_SIGNAL_USR2;
285 return linux_gdb_signal_from_target (gdbarch, signal);
288 /* Implementation of `gdbarch_gdb_signal_to_target', as defined in
292 alpha_linux_gdb_signal_to_target (struct gdbarch *gdbarch,
293 enum gdb_signal signal)
298 return ALPHA_LINUX_SIGEMT;
301 return ALPHA_LINUX_SIGBUS;
304 return ALPHA_LINUX_SIGSYS;
307 return ALPHA_LINUX_SIGURG;
309 case GDB_SIGNAL_STOP:
310 return ALPHA_LINUX_SIGSTOP;
312 case GDB_SIGNAL_TSTP:
313 return ALPHA_LINUX_SIGTSTP;
315 case GDB_SIGNAL_CONT:
316 return ALPHA_LINUX_SIGCONT;
318 case GDB_SIGNAL_CHLD:
319 return ALPHA_LINUX_SIGCHLD;
322 return ALPHA_LINUX_SIGIO;
324 case GDB_SIGNAL_INFO:
325 return ALPHA_LINUX_SIGINFO;
327 case GDB_SIGNAL_USR1:
328 return ALPHA_LINUX_SIGUSR1;
330 case GDB_SIGNAL_USR2:
331 return ALPHA_LINUX_SIGUSR2;
333 case GDB_SIGNAL_POLL:
334 return ALPHA_LINUX_SIGPOLL;
337 return ALPHA_LINUX_SIGPWR;
340 return linux_gdb_signal_to_target (gdbarch, signal);
344 alpha_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
346 struct gdbarch_tdep *tdep;
348 linux_init_abi (info, gdbarch);
350 /* Hook into the DWARF CFI frame unwinder. */
351 alpha_dwarf2_init_abi (info, gdbarch);
353 /* Hook into the MDEBUG frame unwinder. */
354 alpha_mdebug_init_abi (info, gdbarch);
356 tdep = gdbarch_tdep (gdbarch);
357 tdep->dynamic_sigtramp_offset = alpha_linux_sigtramp_offset;
358 tdep->sigcontext_addr = alpha_linux_sigcontext_addr;
359 tdep->pc_in_sigtramp = alpha_linux_pc_in_sigtramp;
361 tdep->jb_elt_size = 8;
363 set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
365 set_solib_svr4_fetch_link_map_offsets
366 (gdbarch, svr4_lp64_fetch_link_map_offsets);
368 /* Enable TLS support. */
369 set_gdbarch_fetch_tls_load_module_address (gdbarch,
370 svr4_fetch_objfile_link_map);
372 set_gdbarch_regset_from_core_section
373 (gdbarch, alpha_linux_regset_from_core_section);
375 set_gdbarch_gdb_signal_from_target (gdbarch,
376 alpha_linux_gdb_signal_from_target);
377 set_gdbarch_gdb_signal_to_target (gdbarch,
378 alpha_linux_gdb_signal_to_target);
381 /* Provide a prototype to silence -Wmissing-prototypes. */
382 extern initialize_file_ftype _initialize_alpha_linux_tdep;
385 _initialize_alpha_linux_tdep (void)
387 gdbarch_register_osabi (bfd_arch_alpha, 0, GDB_OSABI_LINUX,
388 alpha_linux_init_abi);