1 /* Target-dependent code for GNU/Linux running on PA-RISC, for GDB.
3 Copyright (C) 2004-2024 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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/>. */
25 #include "solib-svr4.h"
26 #include "glibc-tdep.h"
27 #include "frame-unwind.h"
28 #include "trad-frame.h"
29 #include "dwarf2/frame.h"
33 #include "hppa-tdep.h"
34 #include "linux-tdep.h"
35 #include "elf/common.h"
37 /* Map DWARF DBX register numbers to GDB register numbers. */
39 hppa_dwarf_reg_to_regnum (struct gdbarch
*gdbarch
, int reg
)
41 /* The general registers and the sar are the same in both sets. */
42 if (reg
>= 0 && reg
<= 32)
45 /* fr4-fr31 (left and right halves) are mapped from 72. */
46 if (reg
>= 72 && reg
<= 72 + 28 * 2)
47 return HPPA_FP4_REGNUM
+ (reg
- 72);
53 hppa_linux_target_write_pc (struct regcache
*regcache
, CORE_ADDR v
)
55 /* Probably this should be done by the kernel, but it isn't. */
56 regcache_cooked_write_unsigned (regcache
, HPPA_PCOQ_HEAD_REGNUM
, v
| 0x3);
57 regcache_cooked_write_unsigned (regcache
,
58 HPPA_PCOQ_TAIL_REGNUM
, (v
+ 4) | 0x3);
61 /* An instruction to match. */
64 unsigned int data
; /* See if it matches this.... */
65 unsigned int mask
; /* ... with this mask. */
68 static struct insn_pattern hppa_sigtramp
[] = {
69 /* ldi 0, %r25 or ldi 1, %r25 */
70 { 0x34190000, 0xfffffffd },
71 /* ldi __NR_rt_sigreturn, %r20 */
72 { 0x3414015a, 0xffffffff },
73 /* be,l 0x100(%sr2, %r0), %sr0, %r31 */
74 { 0xe4008200, 0xffffffff },
76 { 0x08000240, 0xffffffff },
80 #define HPPA_MAX_INSN_PATTERN_LEN (4)
82 /* Return non-zero if the instructions at PC match the series
83 described in PATTERN, or zero otherwise. PATTERN is an array of
84 'struct insn_pattern' objects, terminated by an entry whose mask is
87 When the match is successful, fill INSN[i] with what PATTERN[i]
90 insns_match_pattern (struct gdbarch
*gdbarch
, CORE_ADDR pc
,
91 struct insn_pattern
*pattern
,
94 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
98 for (i
= 0; pattern
[i
].mask
; i
++)
102 target_read_memory (npc
, buf
, 4);
103 insn
[i
] = extract_unsigned_integer (buf
, 4, byte_order
);
104 if ((insn
[i
] & pattern
[i
].mask
) == pattern
[i
].data
)
114 /* (This is derived from MD_FALLBACK_FRAME_STATE_FOR in gcc.)
116 Unfortunately, because of various bugs and changes to the kernel,
117 we have several cases to deal with.
119 In 2.4, the signal trampoline is 4 bytes, and pc should point directly at
120 the beginning of the trampoline and struct rt_sigframe.
122 In <= 2.6.5-rc2-pa3, the signal trampoline is 9 bytes, and pc points at
123 the 4th word in the trampoline structure. This is wrong, it should point
124 at the 5th word. This is fixed in 2.6.5-rc2-pa4.
126 To detect these cases, we first take pc, align it to 64-bytes
127 to get the beginning of the signal frame, and then check offsets 0, 4
128 and 5 to see if we found the beginning of the trampoline. This will
129 tell us how to locate the sigcontext structure.
131 Note that with a 2.4 64-bit kernel, the signal context is not properly
132 passed back to userspace so the unwind will not work correctly. */
134 hppa_linux_sigtramp_find_sigcontext (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
136 unsigned int dummy
[HPPA_MAX_INSN_PATTERN_LEN
];
139 /* offsets to try to find the trampoline */
140 static int pcoffs
[] = { 0, 4*4, 5*4 };
141 /* offsets to the rt_sigframe structure */
142 static int sfoffs
[] = { 4*4, 10*4, 10*4 };
145 /* Most of the time, this will be correct. The one case when this will
146 fail is if the user defined an alternate stack, in which case the
147 beginning of the stack will not be align_down (pc, 64). */
148 sp
= align_down (pc
, 64);
150 /* rt_sigreturn trampoline:
151 3419000x ldi 0, %r25 or ldi 1, %r25 (x = 0 or 2)
152 3414015a ldi __NR_rt_sigreturn, %r20
153 e4008200 be,l 0x100(%sr2, %r0), %sr0, %r31
156 for (attempt
= 0; attempt
< ARRAY_SIZE (pcoffs
); attempt
++)
158 if (insns_match_pattern (gdbarch
, sp
+ pcoffs
[attempt
],
159 hppa_sigtramp
, dummy
))
161 offs
= sfoffs
[attempt
];
168 if (insns_match_pattern (gdbarch
, pc
, hppa_sigtramp
, dummy
))
170 /* sigaltstack case: we have no way of knowing which offset to
171 use in this case; default to new kernel handling. If this is
172 wrong the unwinding will fail. */
174 sp
= pc
- pcoffs
[attempt
];
180 /* sp + sfoffs[try] points to a struct rt_sigframe, which contains
181 a struct siginfo and a struct ucontext. struct ucontext contains
182 a struct sigcontext. Return an offset to this sigcontext here. Too
183 bad we cannot include system specific headers :-(.
184 sizeof(struct siginfo) == 128
185 offsetof(struct ucontext, uc_mcontext) == 24. */
186 return sp
+ sfoffs
[attempt
] + 128 + 24;
189 struct hppa_linux_sigtramp_unwind_cache
192 trad_frame_saved_reg
*saved_regs
;
195 static struct hppa_linux_sigtramp_unwind_cache
*
196 hppa_linux_sigtramp_frame_unwind_cache (const frame_info_ptr
&this_frame
,
199 struct gdbarch
*gdbarch
= get_frame_arch (this_frame
);
200 struct hppa_linux_sigtramp_unwind_cache
*info
;
205 return (struct hppa_linux_sigtramp_unwind_cache
*) *this_cache
;
207 info
= FRAME_OBSTACK_ZALLOC (struct hppa_linux_sigtramp_unwind_cache
);
209 info
->saved_regs
= trad_frame_alloc_saved_regs (this_frame
);
211 pc
= get_frame_pc (this_frame
);
212 scptr
= hppa_linux_sigtramp_find_sigcontext (gdbarch
, pc
);
214 /* structure of struct sigcontext:
217 unsigned long sc_flags;
218 unsigned long sc_gr[32];
219 unsigned long long sc_fr[32];
220 unsigned long sc_iasq[2];
221 unsigned long sc_iaoq[2];
222 unsigned long sc_sar; */
227 /* GR[0] is the psw. */
228 info
->saved_regs
[HPPA_IPSW_REGNUM
].set_addr (scptr
);
231 /* General registers. */
232 for (i
= 1; i
< 32; i
++)
234 info
->saved_regs
[HPPA_R0_REGNUM
+ i
].set_addr (scptr
);
238 /* Pad to long long boundary. */
241 /* FP regs; FP0-3 are not restored. */
244 for (i
= 4; i
< 32; i
++)
246 info
->saved_regs
[HPPA_FP0_REGNUM
+ (i
* 2)].set_addr (scptr
);
248 info
->saved_regs
[HPPA_FP0_REGNUM
+ (i
* 2) + 1].set_addr (scptr
);
253 info
->saved_regs
[HPPA_PCSQ_HEAD_REGNUM
].set_addr (scptr
);
255 info
->saved_regs
[HPPA_PCSQ_TAIL_REGNUM
].set_addr (scptr
);
258 info
->saved_regs
[HPPA_PCOQ_HEAD_REGNUM
].set_addr (scptr
);
260 info
->saved_regs
[HPPA_PCOQ_TAIL_REGNUM
].set_addr (scptr
);
263 info
->saved_regs
[HPPA_SAR_REGNUM
].set_addr (scptr
);
265 info
->base
= get_frame_register_unsigned (this_frame
, HPPA_SP_REGNUM
);
271 hppa_linux_sigtramp_frame_this_id (const frame_info_ptr
&this_frame
,
272 void **this_prologue_cache
,
273 struct frame_id
*this_id
)
275 struct hppa_linux_sigtramp_unwind_cache
*info
276 = hppa_linux_sigtramp_frame_unwind_cache (this_frame
, this_prologue_cache
);
277 *this_id
= frame_id_build (info
->base
, get_frame_pc (this_frame
));
280 static struct value
*
281 hppa_linux_sigtramp_frame_prev_register (const frame_info_ptr
&this_frame
,
282 void **this_prologue_cache
,
285 struct hppa_linux_sigtramp_unwind_cache
*info
286 = hppa_linux_sigtramp_frame_unwind_cache (this_frame
, this_prologue_cache
);
287 return hppa_frame_prev_register_helper (this_frame
,
288 info
->saved_regs
, regnum
);
291 /* hppa-linux always uses "new-style" rt-signals. The signal handler's return
292 address should point to a signal trampoline on the stack. The signal
293 trampoline is embedded in a rt_sigframe structure that is aligned on
294 the stack. We take advantage of the fact that sp must be 64-byte aligned,
295 and the trampoline is small, so by rounding down the trampoline address
296 we can find the beginning of the struct rt_sigframe. */
298 hppa_linux_sigtramp_frame_sniffer (const struct frame_unwind
*self
,
299 const frame_info_ptr
&this_frame
,
300 void **this_prologue_cache
)
302 struct gdbarch
*gdbarch
= get_frame_arch (this_frame
);
303 CORE_ADDR pc
= get_frame_pc (this_frame
);
305 if (hppa_linux_sigtramp_find_sigcontext (gdbarch
, pc
))
311 static const struct frame_unwind hppa_linux_sigtramp_frame_unwind
= {
312 "hppa linux sigtramp",
314 default_frame_unwind_stop_reason
,
315 hppa_linux_sigtramp_frame_this_id
,
316 hppa_linux_sigtramp_frame_prev_register
,
318 hppa_linux_sigtramp_frame_sniffer
321 /* Attempt to find (and return) the global pointer for the given
324 This is a rather nasty bit of code searchs for the .dynamic section
325 in the objfile corresponding to the pc of the function we're trying
326 to call. Once it finds the addresses at which the .dynamic section
327 lives in the child process, it scans the Elf32_Dyn entries for a
328 DT_PLTGOT tag. If it finds one of these, the corresponding
329 d_un.d_ptr value is the global pointer. */
332 hppa_linux_find_global_pointer (struct gdbarch
*gdbarch
,
333 struct value
*function
)
335 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
336 struct obj_section
*faddr_sect
;
339 faddr
= value_as_address (function
);
341 /* Is this a plabel? If so, dereference it to get the gp value. */
349 status
= target_read_memory (faddr
+ 4, buf
, sizeof (buf
));
351 return extract_unsigned_integer (buf
, sizeof (buf
), byte_order
);
354 /* If the address is in the plt section, then the real function hasn't
355 yet been fixed up by the linker so we cannot determine the gp of
357 if (in_plt_section (faddr
))
360 faddr_sect
= find_pc_section (faddr
);
361 if (faddr_sect
!= NULL
)
363 for (obj_section
*osect
: faddr_sect
->objfile
->sections ())
365 if (strcmp (osect
->the_bfd_section
->name
, ".dynamic") == 0)
367 CORE_ADDR addr
, endaddr
;
369 addr
= osect
->addr ();
370 endaddr
= osect
->endaddr ();
372 while (addr
< endaddr
)
378 status
= target_read_memory (addr
, buf
, sizeof (buf
));
381 tag
= extract_signed_integer (buf
, byte_order
);
383 if (tag
== DT_PLTGOT
)
385 CORE_ADDR global_pointer
;
387 status
= target_read_memory (addr
+ 4, buf
,
392 = extract_unsigned_integer (buf
, sizeof (buf
),
395 return global_pointer
;
411 * Registers saved in a coredump:
416 * sar, iir, isr, ior, ipsw
422 static const struct regcache_map_entry hppa_linux_gregmap
[] =
424 { 32, HPPA_R0_REGNUM
},
425 { 1, HPPA_SR4_REGNUM
+1 },
426 { 1, HPPA_SR4_REGNUM
+2 },
427 { 1, HPPA_SR4_REGNUM
+3 },
428 { 1, HPPA_SR4_REGNUM
+4 },
429 { 1, HPPA_SR4_REGNUM
},
430 { 1, HPPA_SR4_REGNUM
+5 },
431 { 1, HPPA_SR4_REGNUM
+6 },
432 { 1, HPPA_SR4_REGNUM
+7 },
433 { 1, HPPA_PCOQ_HEAD_REGNUM
},
434 { 1, HPPA_PCOQ_TAIL_REGNUM
},
435 { 1, HPPA_PCSQ_HEAD_REGNUM
},
436 { 1, HPPA_PCSQ_TAIL_REGNUM
},
437 { 1, HPPA_SAR_REGNUM
},
438 { 1, HPPA_IIR_REGNUM
},
439 { 1, HPPA_ISR_REGNUM
},
440 { 1, HPPA_IOR_REGNUM
},
441 { 1, HPPA_IPSW_REGNUM
},
442 { 1, HPPA_RCR_REGNUM
},
443 { 8, HPPA_TR0_REGNUM
},
444 { 4, HPPA_PID0_REGNUM
},
445 { 1, HPPA_CCR_REGNUM
},
446 { 1, HPPA_EIEM_REGNUM
},
450 static const struct regcache_map_entry hppa_linux_fpregmap
[] =
452 /* FIXME: Only works for 32-bit mode. In 64-bit mode there should
453 be 32 fpregs, 8 bytes each. */
454 { 64, HPPA_FP0_REGNUM
, 4 },
458 /* HPPA Linux kernel register set. */
459 static const struct regset hppa_linux_regset
=
462 regcache_supply_regset
, regcache_collect_regset
465 static const struct regset hppa_linux_fpregset
=
468 regcache_supply_regset
, regcache_collect_regset
472 hppa_linux_iterate_over_regset_sections (struct gdbarch
*gdbarch
,
473 iterate_over_regset_sections_cb
*cb
,
475 const struct regcache
*regcache
)
477 hppa_gdbarch_tdep
*tdep
= gdbarch_tdep
<hppa_gdbarch_tdep
> (gdbarch
);
479 cb (".reg", 80 * tdep
->bytes_per_address
, 80 * tdep
->bytes_per_address
,
480 &hppa_linux_regset
, NULL
, cb_data
);
481 cb (".reg2", 64 * 4, 64 * 4, &hppa_linux_fpregset
, NULL
, cb_data
);
485 hppa_linux_init_abi (struct gdbarch_info info
, struct gdbarch
*gdbarch
)
487 hppa_gdbarch_tdep
*tdep
= gdbarch_tdep
<hppa_gdbarch_tdep
> (gdbarch
);
489 linux_init_abi (info
, gdbarch
, 0);
491 /* GNU/Linux is always ELF. */
494 tdep
->find_global_pointer
= hppa_linux_find_global_pointer
;
496 set_gdbarch_write_pc (gdbarch
, hppa_linux_target_write_pc
);
498 frame_unwind_append_unwinder (gdbarch
, &hppa_linux_sigtramp_frame_unwind
);
500 /* GNU/Linux uses SVR4-style shared libraries. */
501 set_solib_svr4_fetch_link_map_offsets
502 (gdbarch
, linux_ilp32_fetch_link_map_offsets
);
504 tdep
->in_solib_call_trampoline
= hppa_in_solib_call_trampoline
;
505 set_gdbarch_skip_trampoline_code (gdbarch
, hppa_skip_trampoline_code
);
507 /* GNU/Linux uses the dynamic linker included in the GNU C Library. */
508 set_gdbarch_skip_solib_resolver (gdbarch
, glibc_skip_solib_resolver
);
510 /* On hppa-linux, currently, sizeof(long double) == 8. There has been
511 some discussions to support 128-bit long double, but it requires some
512 more work in gcc and glibc first. */
513 set_gdbarch_long_double_bit (gdbarch
, 64);
514 set_gdbarch_long_double_format (gdbarch
, floatformats_ieee_double
);
516 set_gdbarch_iterate_over_regset_sections
517 (gdbarch
, hppa_linux_iterate_over_regset_sections
);
519 set_gdbarch_dwarf2_reg_to_regnum (gdbarch
, hppa_dwarf_reg_to_regnum
);
521 /* Enable TLS support. */
522 set_gdbarch_fetch_tls_load_module_address (gdbarch
,
523 svr4_fetch_objfile_link_map
);
526 void _initialize_hppa_linux_tdep ();
528 _initialize_hppa_linux_tdep ()
530 gdbarch_register_osabi (bfd_arch_hppa
, 0, GDB_OSABI_LINUX
,
531 hppa_linux_init_abi
);
532 gdbarch_register_osabi (bfd_arch_hppa
, bfd_mach_hppa20w
,
533 GDB_OSABI_LINUX
, hppa_linux_init_abi
);