mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-27 04:52:05 +08:00
3666a04883
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
616 lines
21 KiB
C
616 lines
21 KiB
C
/* Common target-dependent code for ppc64 GDB, the GNU debugger.
|
|
|
|
Copyright (C) 1986-2021 Free Software Foundation, Inc.
|
|
|
|
This file is part of GDB.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
|
|
|
#include "defs.h"
|
|
#include "frame.h"
|
|
#include "gdbcore.h"
|
|
#include "infrun.h"
|
|
#include "ppc-tdep.h"
|
|
#include "ppc64-tdep.h"
|
|
#include "elf-bfd.h"
|
|
|
|
/* Macros for matching instructions. Note that, since all the
|
|
operands are masked off before they're or-ed into the instruction,
|
|
you can use -1 to make masks. */
|
|
|
|
#define insn_d(opcd, rts, ra, d) \
|
|
((((unsigned (opcd)) & 0x3f) << 26) \
|
|
| (((unsigned (rts)) & 0x1f) << 21) \
|
|
| (((unsigned (ra)) & 0x1f) << 16) \
|
|
| ((unsigned (d)) & 0xffff))
|
|
|
|
#define insn_ds(opcd, rts, ra, d, xo) \
|
|
((((unsigned (opcd)) & 0x3f) << 26) \
|
|
| (((unsigned (rts)) & 0x1f) << 21) \
|
|
| (((unsigned (ra)) & 0x1f) << 16) \
|
|
| ((unsigned (d)) & 0xfffc) \
|
|
| ((unsigned (xo)) & 0x3))
|
|
|
|
#define insn_xfx(opcd, rts, spr, xo) \
|
|
((((unsigned (opcd)) & 0x3f) << 26) \
|
|
| (((unsigned (rts)) & 0x1f) << 21) \
|
|
| (((unsigned (spr)) & 0x1f) << 16) \
|
|
| (((unsigned (spr)) & 0x3e0) << 6) \
|
|
| (((unsigned (xo)) & 0x3ff) << 1))
|
|
|
|
/* PLT_OFF is the TOC-relative offset of a 64-bit PowerPC PLT entry.
|
|
Return the function's entry point. */
|
|
|
|
static CORE_ADDR
|
|
ppc64_plt_entry_point (struct frame_info *frame, CORE_ADDR plt_off)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
|
|
CORE_ADDR tocp;
|
|
|
|
if (execution_direction == EXEC_REVERSE)
|
|
{
|
|
/* If executing in reverse, r2 will have been stored to the stack. */
|
|
CORE_ADDR sp = get_frame_register_unsigned (frame,
|
|
tdep->ppc_gp0_regnum + 1);
|
|
unsigned int sp_off = tdep->elf_abi == POWERPC_ELF_V1 ? 40 : 24;
|
|
tocp = read_memory_unsigned_integer (sp + sp_off, 8, byte_order);
|
|
}
|
|
else
|
|
tocp = get_frame_register_unsigned (frame, tdep->ppc_gp0_regnum + 2);
|
|
|
|
/* The first word of the PLT entry is the function entry point. */
|
|
return read_memory_unsigned_integer (tocp + plt_off, 8, byte_order);
|
|
}
|
|
|
|
/* Patterns for the standard linkage functions. These are built by
|
|
build_plt_stub in bfd/elf64-ppc.c. */
|
|
|
|
/* Old ELFv1 PLT call stub. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage1[] =
|
|
{
|
|
/* addis r12, r2, <any> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (15, 12, 2, 0), 0 },
|
|
|
|
/* std r2, 40(r1) */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 40, 0), 0 },
|
|
|
|
/* ld r11, <any>(r12) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 12, 0, 0), 0 },
|
|
|
|
/* addis r12, r12, 1 <optional> */
|
|
{ insn_d (-1, -1, -1, -1), insn_d (15, 12, 12, 1), 1 },
|
|
|
|
/* ld r2, <any>(r12) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 2, 12, 0, 0), 0 },
|
|
|
|
/* addis r12, r12, 1 <optional> */
|
|
{ insn_d (-1, -1, -1, -1), insn_d (15, 12, 12, 1), 1 },
|
|
|
|
/* mtctr r11 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 11, 9, 467), 0 },
|
|
|
|
/* ld r11, <any>(r12) <optional> */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 12, 0, 0), 1 },
|
|
|
|
/* bctr */
|
|
{ (unsigned) -1, 0x4e800420, 0 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* ELFv1 PLT call stub to access PLT entries more than +/- 32k from r2.
|
|
Also supports older stub with different placement of std 2,40(1),
|
|
a stub that omits the std 2,40(1), and both versions of power7
|
|
thread safety read barriers. Note that there are actually two more
|
|
instructions following "cmpldi r2, 0", "bnectr+" and "b <glink_i>",
|
|
but there isn't any need to match them. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage2[] =
|
|
{
|
|
/* std r2, 40(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 40, 0), 1 },
|
|
|
|
/* addis r12, r2, <any> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (15, 12, 2, 0), 0 },
|
|
|
|
/* std r2, 40(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 40, 0), 1 },
|
|
|
|
/* ld r11, <any>(r12) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 12, 0, 0), 0 },
|
|
|
|
/* addi r12, r12, <any> <optional> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (14, 12, 12, 0), 1 },
|
|
|
|
/* mtctr r11 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 11, 9, 467), 0 },
|
|
|
|
/* xor r11, r11, r11 <optional> */
|
|
{ (unsigned) -1, 0x7d6b5a78, 1 },
|
|
|
|
/* add r12, r12, r11 <optional> */
|
|
{ (unsigned) -1, 0x7d8c5a14, 1 },
|
|
|
|
/* ld r2, <any>(r12) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 2, 12, 0, 0), 0 },
|
|
|
|
/* ld r11, <any>(r12) <optional> */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 12, 0, 0), 1 },
|
|
|
|
/* bctr <optional> */
|
|
{ (unsigned) -1, 0x4e800420, 1 },
|
|
|
|
/* cmpldi r2, 0 <optional> */
|
|
{ (unsigned) -1, 0x28220000, 1 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* ELFv1 PLT call stub to access PLT entries within +/- 32k of r2. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage3[] =
|
|
{
|
|
/* std r2, 40(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 40, 0), 1 },
|
|
|
|
/* ld r11, <any>(r2) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 2, 0, 0), 0 },
|
|
|
|
/* addi r2, r2, <any> <optional> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (14, 2, 2, 0), 1 },
|
|
|
|
/* mtctr r11 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 11, 9, 467), 0 },
|
|
|
|
/* xor r11, r11, r11 <optional> */
|
|
{ (unsigned) -1, 0x7d6b5a78, 1 },
|
|
|
|
/* add r2, r2, r11 <optional> */
|
|
{ (unsigned) -1, 0x7c425a14, 1 },
|
|
|
|
/* ld r11, <any>(r2) <optional> */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 2, 0, 0), 1 },
|
|
|
|
/* ld r2, <any>(r2) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 2, 2, 0, 0), 0 },
|
|
|
|
/* bctr <optional> */
|
|
{ (unsigned) -1, 0x4e800420, 1 },
|
|
|
|
/* cmpldi r2, 0 <optional> */
|
|
{ (unsigned) -1, 0x28220000, 1 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* ELFv1 PLT call stub to access PLT entries more than +/- 32k from r2.
|
|
A more modern variant of ppc64_standard_linkage2 differing in
|
|
register usage. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage4[] =
|
|
{
|
|
/* std r2, 40(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 40, 0), 1 },
|
|
|
|
/* addis r11, r2, <any> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (15, 11, 2, 0), 0 },
|
|
|
|
/* ld r12, <any>(r11) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 12, 11, 0, 0), 0 },
|
|
|
|
/* addi r11, r11, <any> <optional> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (14, 11, 11, 0), 1 },
|
|
|
|
/* mtctr r12 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 12, 9, 467), 0 },
|
|
|
|
/* xor r2, r12, r12 <optional> */
|
|
{ (unsigned) -1, 0x7d826278, 1 },
|
|
|
|
/* add r11, r11, r2 <optional> */
|
|
{ (unsigned) -1, 0x7d6b1214, 1 },
|
|
|
|
/* ld r2, <any>(r11) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 2, 11, 0, 0), 0 },
|
|
|
|
/* ld r11, <any>(r11) <optional> */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 11, 0, 0), 1 },
|
|
|
|
/* bctr <optional> */
|
|
{ (unsigned) -1, 0x4e800420, 1 },
|
|
|
|
/* cmpldi r2, 0 <optional> */
|
|
{ (unsigned) -1, 0x28220000, 1 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* ELFv1 PLT call stub to access PLT entries within +/- 32k of r2.
|
|
A more modern variant of ppc64_standard_linkage3 differing in
|
|
register usage. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage5[] =
|
|
{
|
|
/* std r2, 40(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 40, 0), 1 },
|
|
|
|
/* ld r12, <any>(r2) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 12, 2, 0, 0), 0 },
|
|
|
|
/* addi r2, r2, <any> <optional> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (14, 2, 2, 0), 1 },
|
|
|
|
/* mtctr r12 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 12, 9, 467), 0 },
|
|
|
|
/* xor r11, r12, r12 <optional> */
|
|
{ (unsigned) -1, 0x7d8b6278, 1 },
|
|
|
|
/* add r2, r2, r11 <optional> */
|
|
{ (unsigned) -1, 0x7c425a14, 1 },
|
|
|
|
/* ld r11, <any>(r2) <optional> */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 11, 2, 0, 0), 1 },
|
|
|
|
/* ld r2, <any>(r2) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 2, 2, 0, 0), 0 },
|
|
|
|
/* bctr <optional> */
|
|
{ (unsigned) -1, 0x4e800420, 1 },
|
|
|
|
/* cmpldi r2, 0 <optional> */
|
|
{ (unsigned) -1, 0x28220000, 1 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* ELFv2 PLT call stub to access PLT entries more than +/- 32k from r2. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage6[] =
|
|
{
|
|
/* std r2, 24(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 24, 0), 1 },
|
|
|
|
/* addis r11, r2, <any> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (15, 11, 2, 0), 0 },
|
|
|
|
/* ld r12, <any>(r11) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 12, 11, 0, 0), 0 },
|
|
|
|
/* mtctr r12 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 12, 9, 467), 0 },
|
|
|
|
/* bctr */
|
|
{ (unsigned) -1, 0x4e800420, 0 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* ELFv2 PLT call stub to access PLT entries within +/- 32k of r2. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage7[] =
|
|
{
|
|
/* std r2, 24(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 24, 0), 1 },
|
|
|
|
/* ld r12, <any>(r2) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 12, 2, 0, 0), 0 },
|
|
|
|
/* mtctr r12 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 12, 9, 467), 0 },
|
|
|
|
/* bctr */
|
|
{ (unsigned) -1, 0x4e800420, 0 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* ELFv2 PLT call stub to access PLT entries more than +/- 32k from r2,
|
|
supporting fusion. */
|
|
|
|
static const struct ppc_insn_pattern ppc64_standard_linkage8[] =
|
|
{
|
|
/* std r2, 24(r1) <optional> */
|
|
{ (unsigned) -1, insn_ds (62, 2, 1, 24, 0), 1 },
|
|
|
|
/* addis r12, r2, <any> */
|
|
{ insn_d (-1, -1, -1, 0), insn_d (15, 12, 2, 0), 0 },
|
|
|
|
/* ld r12, <any>(r12) */
|
|
{ insn_ds (-1, -1, -1, 0, -1), insn_ds (58, 12, 12, 0, 0), 0 },
|
|
|
|
/* mtctr r12 */
|
|
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 12, 9, 467), 0 },
|
|
|
|
/* bctr */
|
|
{ (unsigned) -1, 0x4e800420, 0 },
|
|
|
|
{ 0, 0, 0 }
|
|
};
|
|
|
|
/* When the dynamic linker is doing lazy symbol resolution, the first
|
|
call to a function in another object will go like this:
|
|
|
|
- The user's function calls the linkage function:
|
|
|
|
100003d4: 4b ff ff ad bl 10000380 <nnnn.plt_call.printf>
|
|
100003d8: e8 41 00 28 ld r2,40(r1)
|
|
|
|
- The linkage function loads the entry point and toc pointer from
|
|
the function descriptor in the PLT, and jumps to it:
|
|
|
|
<nnnn.plt_call.printf>:
|
|
10000380: f8 41 00 28 std r2,40(r1)
|
|
10000384: e9 62 80 78 ld r11,-32648(r2)
|
|
10000388: 7d 69 03 a6 mtctr r11
|
|
1000038c: e8 42 80 80 ld r2,-32640(r2)
|
|
10000390: 28 22 00 00 cmpldi r2,0
|
|
10000394: 4c e2 04 20 bnectr+
|
|
10000398: 48 00 03 a0 b 10000738 <printf@plt>
|
|
|
|
- But since this is the first time that PLT entry has been used, it
|
|
sends control to its glink entry. That loads the number of the
|
|
PLT entry and jumps to the common glink0 code:
|
|
|
|
<printf@plt>:
|
|
10000738: 38 00 00 01 li r0,1
|
|
1000073c: 4b ff ff bc b 100006f8 <__glink_PLTresolve>
|
|
|
|
- The common glink0 code then transfers control to the dynamic
|
|
linker's fixup code:
|
|
|
|
100006f0: 0000000000010440 .quad plt0 - (. + 16)
|
|
<__glink_PLTresolve>:
|
|
100006f8: 7d 88 02 a6 mflr r12
|
|
100006fc: 42 9f 00 05 bcl 20,4*cr7+so,10000700
|
|
10000700: 7d 68 02 a6 mflr r11
|
|
10000704: e8 4b ff f0 ld r2,-16(r11)
|
|
10000708: 7d 88 03 a6 mtlr r12
|
|
1000070c: 7d 82 5a 14 add r12,r2,r11
|
|
10000710: e9 6c 00 00 ld r11,0(r12)
|
|
10000714: e8 4c 00 08 ld r2,8(r12)
|
|
10000718: 7d 69 03 a6 mtctr r11
|
|
1000071c: e9 6c 00 10 ld r11,16(r12)
|
|
10000720: 4e 80 04 20 bctr
|
|
|
|
Eventually, this code will figure out how to skip all of this,
|
|
including the dynamic linker. At the moment, we just get through
|
|
the linkage function. */
|
|
|
|
/* If the current thread is about to execute a series of instructions
|
|
matching the ppc64_standard_linkage pattern, and INSN is the result
|
|
from that pattern match, return the code address to which the
|
|
standard linkage function will send them. (This doesn't deal with
|
|
dynamic linker lazy symbol resolution stubs.) */
|
|
|
|
static CORE_ADDR
|
|
ppc64_standard_linkage1_target (struct frame_info *frame, unsigned int *insn)
|
|
{
|
|
CORE_ADDR plt_off = ((ppc_insn_d_field (insn[0]) << 16)
|
|
+ ppc_insn_ds_field (insn[2]));
|
|
|
|
return ppc64_plt_entry_point (frame, plt_off);
|
|
}
|
|
|
|
static CORE_ADDR
|
|
ppc64_standard_linkage2_target (struct frame_info *frame, unsigned int *insn)
|
|
{
|
|
CORE_ADDR plt_off = ((ppc_insn_d_field (insn[1]) << 16)
|
|
+ ppc_insn_ds_field (insn[3]));
|
|
|
|
return ppc64_plt_entry_point (frame, plt_off);
|
|
}
|
|
|
|
static CORE_ADDR
|
|
ppc64_standard_linkage3_target (struct frame_info *frame, unsigned int *insn)
|
|
{
|
|
CORE_ADDR plt_off = ppc_insn_ds_field (insn[1]);
|
|
|
|
return ppc64_plt_entry_point (frame, plt_off);
|
|
}
|
|
|
|
static CORE_ADDR
|
|
ppc64_standard_linkage4_target (struct frame_info *frame, unsigned int *insn)
|
|
{
|
|
CORE_ADDR plt_off = ((ppc_insn_d_field (insn[1]) << 16)
|
|
+ ppc_insn_ds_field (insn[2]));
|
|
|
|
return ppc64_plt_entry_point (frame, plt_off);
|
|
}
|
|
|
|
|
|
/* Given that we've begun executing a call trampoline at PC, return
|
|
the entry point of the function the trampoline will go to.
|
|
|
|
When the execution direction is EXEC_REVERSE, scan backward to
|
|
check whether we are in the middle of a PLT stub. */
|
|
|
|
static CORE_ADDR
|
|
ppc64_skip_trampoline_code_1 (struct frame_info *frame, CORE_ADDR pc)
|
|
{
|
|
#define MAX(a,b) ((a) > (b) ? (a) : (b))
|
|
unsigned int insns[MAX (MAX (MAX (ARRAY_SIZE (ppc64_standard_linkage1),
|
|
ARRAY_SIZE (ppc64_standard_linkage2)),
|
|
MAX (ARRAY_SIZE (ppc64_standard_linkage3),
|
|
ARRAY_SIZE (ppc64_standard_linkage4))),
|
|
MAX (MAX (ARRAY_SIZE (ppc64_standard_linkage5),
|
|
ARRAY_SIZE (ppc64_standard_linkage6)),
|
|
MAX (ARRAY_SIZE (ppc64_standard_linkage7),
|
|
ARRAY_SIZE (ppc64_standard_linkage8))))
|
|
- 1];
|
|
CORE_ADDR target;
|
|
int scan_limit, i;
|
|
|
|
scan_limit = 1;
|
|
/* When reverse-debugging, scan backward to check whether we are
|
|
in the middle of trampoline code. */
|
|
if (execution_direction == EXEC_REVERSE)
|
|
scan_limit = ARRAY_SIZE (insns) - 1;
|
|
|
|
for (i = 0; i < scan_limit; i++)
|
|
{
|
|
if (i < ARRAY_SIZE (ppc64_standard_linkage8) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage8, insns))
|
|
pc = ppc64_standard_linkage4_target (frame, insns);
|
|
else if (i < ARRAY_SIZE (ppc64_standard_linkage7) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage7,
|
|
insns))
|
|
pc = ppc64_standard_linkage3_target (frame, insns);
|
|
else if (i < ARRAY_SIZE (ppc64_standard_linkage6) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage6,
|
|
insns))
|
|
pc = ppc64_standard_linkage4_target (frame, insns);
|
|
else if (i < ARRAY_SIZE (ppc64_standard_linkage5) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage5,
|
|
insns)
|
|
&& (insns[8] != 0 || insns[9] != 0))
|
|
pc = ppc64_standard_linkage3_target (frame, insns);
|
|
else if (i < ARRAY_SIZE (ppc64_standard_linkage4) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage4,
|
|
insns)
|
|
&& (insns[9] != 0 || insns[10] != 0))
|
|
pc = ppc64_standard_linkage4_target (frame, insns);
|
|
else if (i < ARRAY_SIZE (ppc64_standard_linkage3) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage3,
|
|
insns)
|
|
&& (insns[8] != 0 || insns[9] != 0))
|
|
pc = ppc64_standard_linkage3_target (frame, insns);
|
|
else if (i < ARRAY_SIZE (ppc64_standard_linkage2) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage2,
|
|
insns)
|
|
&& (insns[10] != 0 || insns[11] != 0))
|
|
pc = ppc64_standard_linkage2_target (frame, insns);
|
|
else if (i < ARRAY_SIZE (ppc64_standard_linkage1) - 1
|
|
&& ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage1,
|
|
insns))
|
|
pc = ppc64_standard_linkage1_target (frame, insns);
|
|
else
|
|
{
|
|
/* Scan backward one more instructions if doesn't match. */
|
|
pc -= 4;
|
|
continue;
|
|
}
|
|
|
|
/* The PLT descriptor will either point to the already resolved target
|
|
address, or else to a glink stub. As the latter carry synthetic @plt
|
|
symbols, find_solib_trampoline_target should be able to resolve them. */
|
|
target = find_solib_trampoline_target (frame, pc);
|
|
return target ? target : pc;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Wrapper of ppc64_skip_trampoline_code_1 checking also
|
|
ppc_elfv2_skip_entrypoint. */
|
|
|
|
CORE_ADDR
|
|
ppc64_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
|
|
pc = ppc64_skip_trampoline_code_1 (frame, pc);
|
|
if (pc != 0 && gdbarch_skip_entrypoint_p (gdbarch))
|
|
pc = gdbarch_skip_entrypoint (gdbarch, pc);
|
|
return pc;
|
|
}
|
|
|
|
/* Support for convert_from_func_ptr_addr (ARCH, ADDR, TARG) on PPC64
|
|
GNU/Linux.
|
|
|
|
Usually a function pointer's representation is simply the address
|
|
of the function. On GNU/Linux on the PowerPC however, a function
|
|
pointer may be a pointer to a function descriptor.
|
|
|
|
For PPC64, a function descriptor is a TOC entry, in a data section,
|
|
which contains three words: the first word is the address of the
|
|
function, the second word is the TOC pointer (r2), and the third word
|
|
is the static chain value.
|
|
|
|
Throughout GDB it is currently assumed that a function pointer contains
|
|
the address of the function, which is not easy to fix. In addition, the
|
|
conversion of a function address to a function pointer would
|
|
require allocation of a TOC entry in the inferior's memory space,
|
|
with all its drawbacks. To be able to call C++ virtual methods in
|
|
the inferior (which are called via function pointers),
|
|
find_function_addr uses this function to get the function address
|
|
from a function pointer.
|
|
|
|
If ADDR points at what is clearly a function descriptor, transform
|
|
it into the address of the corresponding function, if needed. Be
|
|
conservative, otherwise GDB will do the transformation on any
|
|
random addresses such as occur when there is no symbol table. */
|
|
|
|
CORE_ADDR
|
|
ppc64_convert_from_func_ptr_addr (struct gdbarch *gdbarch,
|
|
CORE_ADDR addr,
|
|
struct target_ops *targ)
|
|
{
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
struct target_section *s = target_section_by_addr (targ, addr);
|
|
|
|
/* Check if ADDR points to a function descriptor. */
|
|
if (s && strcmp (s->the_bfd_section->name, ".opd") == 0)
|
|
{
|
|
/* There may be relocations that need to be applied to the .opd
|
|
section. Unfortunately, this function may be called at a time
|
|
where these relocations have not yet been performed -- this can
|
|
happen for example shortly after a library has been loaded with
|
|
dlopen, but ld.so has not yet applied the relocations.
|
|
|
|
To cope with both the case where the relocation has been applied,
|
|
and the case where it has not yet been applied, we do *not* read
|
|
the (maybe) relocated value from target memory, but we instead
|
|
read the non-relocated value from the BFD, and apply the relocation
|
|
offset manually.
|
|
|
|
This makes the assumption that all .opd entries are always relocated
|
|
by the same offset the section itself was relocated. This should
|
|
always be the case for GNU/Linux executables and shared libraries.
|
|
Note that other kind of object files (e.g. those added via
|
|
add-symbol-files) will currently never end up here anyway, as this
|
|
function accesses *target* sections only; only the main exec and
|
|
shared libraries are ever added to the target. */
|
|
|
|
gdb_byte buf[8];
|
|
int res;
|
|
|
|
res = bfd_get_section_contents (s->the_bfd_section->owner,
|
|
s->the_bfd_section,
|
|
&buf, addr - s->addr, 8);
|
|
if (res != 0)
|
|
return (extract_unsigned_integer (buf, 8, byte_order)
|
|
- bfd_section_vma (s->the_bfd_section) + s->addr);
|
|
}
|
|
|
|
return addr;
|
|
}
|
|
|
|
/* A synthetic 'dot' symbols on ppc64 has the udata.p entry pointing
|
|
back to the original ELF symbol it was derived from. Get the size
|
|
from that symbol. */
|
|
|
|
void
|
|
ppc64_elf_make_msymbol_special (asymbol *sym, struct minimal_symbol *msym)
|
|
{
|
|
if ((sym->flags & BSF_SYNTHETIC) != 0 && sym->udata.p != NULL)
|
|
{
|
|
elf_symbol_type *elf_sym = (elf_symbol_type *) sym->udata.p;
|
|
SET_MSYMBOL_SIZE (msym, elf_sym->internal_elf_sym.st_size);
|
|
}
|
|
}
|