/* Common target-dependent code for ppc64 GDB, the GNU debugger.
- Copyright (C) 1986-2013 Free Software Foundation, Inc.
+ Copyright (C) 1986-2015 Free Software Foundation, Inc.
This file is part of GDB.
#include "defs.h"
#include "frame.h"
#include "gdbcore.h"
+#include "infrun.h"
#include "ppc-tdep.h"
#include "ppc64-tdep.h"
#include "elf-bfd.h"
| (((spr) & 0x3e0) << 6) \
| (((xo) & 0x3ff) << 1))
-/* If DESC is the address of a 64-bit PowerPC FreeBSD function
- descriptor, return the descriptor's entry point. */
+/* If PLT is the address of a 64-bit PowerPC PLT entry,
+ return the function's entry point. */
static CORE_ADDR
-ppc64_desc_entry_point (struct gdbarch *gdbarch, CORE_ADDR desc)
+ppc64_plt_entry_point (struct gdbarch *gdbarch, CORE_ADDR plt)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
- /* The first word of the descriptor is the entry point. */
- return (CORE_ADDR) read_memory_unsigned_integer (desc, 8, byte_order);
+ /* The first word of the PLT entry is the function entry point. */
+ return (CORE_ADDR) read_memory_unsigned_integer (plt, 8, byte_order);
}
-/* Pattern for the standard linkage function. These are built by
- build_plt_stub in elf64-ppc.c, whose GLINK argument is always
- zero. */
+/* Patterns for the standard linkage functions. These are built by
+ build_plt_stub in bfd/elf64-ppc.c. */
+
+/* Old ELFv1 PLT call stub. */
static struct ppc_insn_pattern ppc64_standard_linkage1[] =
{
{ 0, 0, 0 }
};
-#define PPC64_STANDARD_LINKAGE1_LEN ARRAY_SIZE (ppc64_standard_linkage1)
+/* 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 struct ppc_insn_pattern ppc64_standard_linkage2[] =
{
+ /* std r2, 40(r1) <optional> */
+ { -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) */
- { -1, insn_ds (62, 2, 1, 40, 0), 0 },
+ /* std r2, 40(r1) <optional> */
+ { -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 },
/* mtctr r11 */
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 11, 9, 467), 0 },
+ /* xor r11, r11, r11 <optional> */
+ { -1, 0x7d6b5a78, 1 },
+
+ /* add r12, r12, r11 <optional> */
+ { -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 */
- { -1, 0x4e800420, 0 },
+ /* bctr <optional> */
+ { -1, 0x4e800420, 1 },
+
+ /* cmpldi r2, 0 <optional> */
+ { -1, 0x28220000, 1 },
{ 0, 0, 0 }
};
-#define PPC64_STANDARD_LINKAGE2_LEN ARRAY_SIZE (ppc64_standard_linkage2)
+/* ELFv1 PLT call stub to access PLT entries within +/- 32k of r2. */
static struct ppc_insn_pattern ppc64_standard_linkage3[] =
{
- /* std r2, 40(r1) */
- { -1, insn_ds (62, 2, 1, 40, 0), 0 },
+ /* std r2, 40(r1) <optional> */
+ { -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 },
/* mtctr r11 */
{ insn_xfx (-1, -1, -1, -1), insn_xfx (31, 11, 9, 467), 0 },
+ /* xor r11, r11, r11 <optional> */
+ { -1, 0x7d6b5a78, 1 },
+
+ /* add r2, r2, r11 <optional> */
+ { -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> */
+ { -1, 0x4e800420, 1 },
+
+ /* cmpldi r2, 0 <optional> */
+ { -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 struct ppc_insn_pattern ppc64_standard_linkage4[] =
+ {
+ /* std r2, 40(r1) <optional> */
+ { -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> */
+ { -1, 0x7d826278, 1 },
+
+ /* add r11, r11, r2 <optional> */
+ { -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> */
+ { -1, 0x4e800420, 1 },
+
+ /* cmpldi r2, 0 <optional> */
+ { -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 struct ppc_insn_pattern ppc64_standard_linkage5[] =
+ {
+ /* std r2, 40(r1) <optional> */
+ { -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> */
+ { -1, 0x7d8b6278, 1 },
+
+ /* add r2, r2, r11 <optional> */
+ { -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> */
+ { -1, 0x4e800420, 1 },
+
+ /* cmpldi r2, 0 <optional> */
+ { -1, 0x28220000, 1 },
+
+ { 0, 0, 0 }
+ };
+
+/* ELFv2 PLT call stub to access PLT entries more than +/- 32k from r2. */
+
+static struct ppc_insn_pattern ppc64_standard_linkage6[] =
+ {
+ /* std r2, 24(r1) <optional> */
+ { -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 */
{ -1, 0x4e800420, 0 },
{ 0, 0, 0 }
};
-#define PPC64_STANDARD_LINKAGE3_LEN ARRAY_SIZE (ppc64_standard_linkage3)
+/* ELFv2 PLT call stub to access PLT entries within +/- 32k of r2. */
+
+static struct ppc_insn_pattern ppc64_standard_linkage7[] =
+ {
+ /* std r2, 24(r1) <optional> */
+ { -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 */
+ { -1, 0x4e800420, 0 },
+
+ { 0, 0, 0 }
+ };
+
+/* ELFv2 PLT call stub to access PLT entries more than +/- 32k from r2,
+ supporting fusion. */
+
+static struct ppc_insn_pattern ppc64_standard_linkage8[] =
+ {
+ /* std r2, 24(r1) <optional> */
+ { -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 */
+ { -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:
- 100007c4: 4b ff fc d5 bl 10000498
- 100007c8: e8 41 00 28 ld r2,40(r1)
+ 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 other stuff) from
- the function descriptor in the PLT, and jumps to it:
+ - The linkage function loads the entry point and toc pointer from
+ the function descriptor in the PLT, and jumps to it:
- 10000498: 3d 82 00 00 addis r12,r2,0
- 1000049c: f8 41 00 28 std r2,40(r1)
- 100004a0: e9 6c 80 98 ld r11,-32616(r12)
- 100004a4: e8 4c 80 a0 ld r2,-32608(r12)
- 100004a8: 7d 69 03 a6 mtctr r11
- 100004ac: e9 6c 80 a8 ld r11,-32600(r12)
- 100004b0: 4e 80 04 20 bctr
+ <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:
+ sends control to its glink entry. That loads the number of the
+ PLT entry and jumps to the common glink0 code:
- 10000c98: 38 00 00 00 li r0,0
- 10000c9c: 4b ff ff dc b 10000c78
+ <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:
-
- 10000c78: e8 41 00 28 ld r2,40(r1)
- 10000c7c: 3d 82 00 00 addis r12,r2,0
- 10000c80: e9 6c 80 80 ld r11,-32640(r12)
- 10000c84: e8 4c 80 88 ld r2,-32632(r12)
- 10000c88: 7d 69 03 a6 mtctr r11
- 10000c8c: e9 6c 80 90 ld r11,-32624(r12)
- 10000c90: 4e 80 04 20 bctr
+ 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
struct gdbarch *gdbarch = get_frame_arch (frame);
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- /* The address of the function descriptor this linkage function
- references. */
- CORE_ADDR desc
+ /* The address of the PLT entry this linkage function references. */
+ CORE_ADDR plt
= ((CORE_ADDR) get_frame_register_unsigned (frame,
tdep->ppc_gp0_regnum + 2)
+ (ppc_insn_d_field (insn[0]) << 16)
+ ppc_insn_ds_field (insn[2]));
- /* The first word of the descriptor is the entry point. Return that. */
- return ppc64_desc_entry_point (gdbarch, desc);
+ return ppc64_plt_entry_point (gdbarch, plt);
}
static CORE_ADDR
struct gdbarch *gdbarch = get_frame_arch (frame);
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- /* The address of the function descriptor this linkage function
- references. */
- CORE_ADDR desc
+ /* The address of the PLT entry this linkage function references. */
+ CORE_ADDR plt
= ((CORE_ADDR) get_frame_register_unsigned (frame,
tdep->ppc_gp0_regnum + 2)
- + (ppc_insn_d_field (insn[0]) << 16)
- + ppc_insn_ds_field (insn[2]));
+ + (ppc_insn_d_field (insn[1]) << 16)
+ + ppc_insn_ds_field (insn[3]));
- /* The first word of the descriptor is the entry point. Return that. */
- return ppc64_desc_entry_point (gdbarch, desc);
+ return ppc64_plt_entry_point (gdbarch, plt);
}
static CORE_ADDR
struct gdbarch *gdbarch = get_frame_arch (frame);
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- /* The address of the function descriptor this linkage function
- references. */
- CORE_ADDR desc
+ /* The address of the PLT entry this linkage function references. */
+ CORE_ADDR plt
= ((CORE_ADDR) get_frame_register_unsigned (frame,
tdep->ppc_gp0_regnum + 2)
+ ppc_insn_ds_field (insn[1]));
- /* The first word of the descriptor is the entry point. Return that. */
- return ppc64_desc_entry_point (gdbarch, desc);
+ return ppc64_plt_entry_point (gdbarch, plt);
+}
+
+static CORE_ADDR
+ppc64_standard_linkage4_target (struct frame_info *frame,
+ CORE_ADDR pc, unsigned int *insn)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ CORE_ADDR plt
+ = ((CORE_ADDR) get_frame_register_unsigned (frame, tdep->ppc_gp0_regnum + 2)
+ + (ppc_insn_d_field (insn[1]) << 16)
+ + ppc_insn_ds_field (insn[2]));
+
+ return ppc64_plt_entry_point (gdbarch, plt);
}
/* Given that we've begun executing a call trampoline at PC, return
- the entry point of the function the trampoline will go to. */
+ 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. */
CORE_ADDR
ppc64_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
{
- unsigned int ppc64_standard_linkage1_insn[PPC64_STANDARD_LINKAGE1_LEN];
- unsigned int ppc64_standard_linkage2_insn[PPC64_STANDARD_LINKAGE2_LEN];
- unsigned int ppc64_standard_linkage3_insn[PPC64_STANDARD_LINKAGE3_LEN];
+#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;
- if (ppc_insns_match_pattern (pc, ppc64_standard_linkage1,
- ppc64_standard_linkage1_insn))
- pc = ppc64_standard_linkage1_target (frame, pc,
- ppc64_standard_linkage1_insn);
- else if (ppc_insns_match_pattern (pc, ppc64_standard_linkage2,
- ppc64_standard_linkage2_insn))
- pc = ppc64_standard_linkage2_target (frame, pc,
- ppc64_standard_linkage2_insn);
- else if (ppc_insns_match_pattern (pc, ppc64_standard_linkage3,
- ppc64_standard_linkage3_insn))
- pc = ppc64_standard_linkage3_target (frame, pc,
- ppc64_standard_linkage3_insn);
- else
- return 0;
-
- /* 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;
+ 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, pc, 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, pc, 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, pc, 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, pc, 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, pc, 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, pc, 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, pc, 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, pc, 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;
}
/* Support for convert_from_func_ptr_addr (ARCH, ADDR, TARG) on PPC64
gdb_byte buf[8];
int res;
- res = bfd_get_section_contents (s->bfd, s->the_bfd_section,
+ 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)
projects / deliverable / binutils-gdb.git / blobdiff