return (CORE_ADDR) read_memory_unsigned_integer (desc, 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 PLT call stub. */
static struct ppc_insn_pattern ppc64_standard_linkage1[] =
{
{ 0, 0, 0 }
};
-#define PPC64_STANDARD_LINKAGE1_LEN ARRAY_SIZE (ppc64_standard_linkage1)
+/* Current 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)
+/* Current 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 */
- { -1, 0x4e800420, 0 },
+ /* bctr <optional> */
+ { -1, 0x4e800420, 1 },
+
+ /* cmpldi r2, 0 <optional> */
+ { -1, 0x28220000, 1 },
{ 0, 0, 0 }
};
-#define PPC64_STANDARD_LINKAGE3_LEN ARRAY_SIZE (ppc64_standard_linkage3)
-
/* 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
CORE_ADDR desc
= ((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);
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 (ARRAY_SIZE (ppc64_standard_linkage1),
+ ARRAY_SIZE (ppc64_standard_linkage2)),
+ ARRAY_SIZE (ppc64_standard_linkage3)) - 1];
CORE_ADDR target;
- 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);
+ if (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 (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 (ppc_insns_match_pattern (frame, pc, ppc64_standard_linkage1, insns))
+ pc = ppc64_standard_linkage1_target (frame, pc, insns);
else
return 0;
projects / binutils-gdb.git / commitdiff