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authorUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
committerUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
commita334319f6530564d22e775935d9c91663623a1b4 (patch)
treeb5877475619e4c938e98757d518bb1e9cbead751 /sysdeps/alpha/dl-machine.h
parent0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (diff)
downloadglibc-a334319f6530564d22e775935d9c91663623a1b4.tar.gz
(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.
Diffstat (limited to 'sysdeps/alpha/dl-machine.h')
-rw-r--r--sysdeps/alpha/dl-machine.h309
1 files changed, 235 insertions, 74 deletions
diff --git a/sysdeps/alpha/dl-machine.h b/sysdeps/alpha/dl-machine.h
index 88c357ea07..780a3a57fd 100644
--- a/sysdeps/alpha/dl-machine.h
+++ b/sysdeps/alpha/dl-machine.h
@@ -1,5 +1,5 @@
/* Machine-dependent ELF dynamic relocation inline functions. Alpha version.
- Copyright (C) 1996-2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 1996-2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <rth@tamu.edu>.
@@ -33,9 +33,6 @@
where the dynamic linker should not map anything. */
#define ELF_MACHINE_USER_ADDRESS_MASK 0x120000000UL
-/* Translate a processor specific dynamic tag to the index in l_info array. */
-#define DT_ALPHA(x) (DT_ALPHA_##x - DT_LOPROC + DT_NUM)
-
/* Return nonzero iff ELF header is compatible with the running host. */
static inline int
elf_machine_matches_host (const Elf64_Ehdr *ehdr)
@@ -58,77 +55,244 @@ elf_machine_dynamic (void)
}
/* Return the run-time load address of the shared object. */
-
static inline Elf64_Addr
elf_machine_load_address (void)
{
- /* This relies on the compiler using gp-relative addresses for static symbols. */
- static void *dot = &dot;
- return (void *)&dot - dot;
+ /* NOTE: While it is generally unfriendly to put data in the text
+ segment, it is only slightly less so when the "data" is an
+ instruction. While we don't have to worry about GLD just yet, an
+ optimizing linker might decide that our "data" is an unreachable
+ instruction and throw it away -- with the right switches, DEC's
+ linker will do this. What ought to happen is we should add
+ something to GAS to allow us access to the new GPREL_HI32/LO32
+ relocation types stolen from OSF/1 3.0. */
+ /* This code relies on the fact that BRADDR relocations do not
+ appear in dynamic relocation tables. Not that that would be very
+ useful anyway -- br/bsr has a 4MB range and the shared libraries
+ are usually many many terabytes away. */
+
+ Elf64_Addr dot;
+ long int zero_disp;
+
+ asm("br %0, 1f\n"
+ "0:\n\t"
+ "br $0, 2f\n"
+ "1:\n\t"
+ ".section\t.data\n"
+ "2:\n\t"
+ ".quad 0b\n\t"
+ ".previous"
+ : "=r"(dot));
+
+ zero_disp = *(int *) dot;
+ zero_disp = (zero_disp << 43) >> 41;
+
+ return dot - *(Elf64_Addr *) (dot + 4 + zero_disp);
}
/* Set up the loaded object described by L so its unrelocated PLT
entries will jump to the on-demand fixup code in dl-runtime.c. */
static inline int
-elf_machine_runtime_setup (struct link_map *map, int lazy, int profile)
+elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
{
- extern char _dl_runtime_resolve_new[] attribute_hidden;
- extern char _dl_runtime_profile_new[] attribute_hidden;
- extern char _dl_runtime_resolve_old[] attribute_hidden;
- extern char _dl_runtime_profile_old[] attribute_hidden;
-
- struct pltgot {
- char *resolve;
- struct link_map *link;
- };
-
- struct pltgot *pg;
- long secureplt;
- char *resolve;
-
- if (map->l_info[DT_JMPREL] == 0 || !lazy)
- return lazy;
-
- /* Check to see if we're using the read-only plt form. */
- secureplt = map->l_info[DT_ALPHA(PLTRO)] != 0;
-
- /* If the binary uses the read-only secure plt format, PG points to
- the .got.plt section, which is the right place for ld.so to place
- its hooks. Otherwise, PG is currently pointing at the start of
- the plt; the hooks go at offset 16. */
- pg = (struct pltgot *) D_PTR (map, l_info[DT_PLTGOT]);
- pg += !secureplt;
-
- /* This function will be called to perform the relocation. They're
- not declared as functions to convince the compiler to use gp
- relative relocations for them. */
- if (secureplt)
- resolve = _dl_runtime_resolve_new;
- else
- resolve = _dl_runtime_resolve_old;
+ Elf64_Addr plt;
+ extern void _dl_runtime_resolve (void);
+ extern void _dl_runtime_profile (void);
- if (__builtin_expect (profile, 0))
+ if (l->l_info[DT_JMPREL] && lazy)
{
- if (secureplt)
- resolve = _dl_runtime_profile_new;
+ /* The GOT entries for the functions in the PLT have not been
+ filled in yet. Their initial contents are directed to the
+ PLT which arranges for the dynamic linker to be called. */
+ plt = D_PTR (l, l_info[DT_PLTGOT]);
+
+ /* This function will be called to perform the relocation. */
+ if (!profile)
+ *(Elf64_Addr *)(plt + 16) = (Elf64_Addr) &_dl_runtime_resolve;
else
- resolve = _dl_runtime_profile_old;
+ {
+ *(Elf64_Addr *)(plt + 16) = (Elf64_Addr) &_dl_runtime_profile;
+
+ if (_dl_name_match_p (GLRO(dl_profile), l))
+ {
+ /* This is the object we are looking for. Say that we really
+ want profiling and the timers are started. */
+ GL(dl_profile_map) = l;
+ }
+ }
+
+ /* Identify this shared object */
+ *(Elf64_Addr *)(plt + 24) = (Elf64_Addr) l;
- if (GLRO(dl_profile) && _dl_name_match_p (GLRO(dl_profile), map))
+ /* If the first instruction of the plt entry is not
+ "br $28, plt0", we have to reinitialize .plt for lazy relocation. */
+ if (*(unsigned int *)(plt + 32) != 0xc39ffff7)
{
- /* This is the object we are looking for. Say that we really
- want profiling and the timers are started. */
- GL(dl_profile_map) = map;
+ unsigned int val = 0xc39ffff7;
+ unsigned int *slot, *end;
+ const Elf64_Rela *rela = (const Elf64_Rela *)
+ D_PTR (l, l_info[DT_JMPREL]);
+ Elf64_Addr l_addr = l->l_addr;
+
+ /* br t12,.+4; ldq t12,12(t12); nop; jmp t12,(t12),.+4 */
+ *(unsigned long *)plt = 0xa77b000cc3600000;
+ *(unsigned long *)(plt + 8) = 0x6b7b000047ff041f;
+ slot = (unsigned int *)(plt + 32);
+ end = (unsigned int *)(plt + 32
+ + l->l_info[DT_PLTRELSZ]->d_un.d_val / 2);
+ while (slot < end)
+ {
+ /* br at,.plt+0 */
+ *slot = val;
+ *(Elf64_Addr *) rela->r_offset = (Elf64_Addr) slot - l_addr;
+ val -= 3;
+ slot += 3;
+ ++rela;
+ }
}
}
- pg->resolve = resolve;
- pg->link = map;
-
return lazy;
}
+/* This code is used in dl-runtime.c to call the `fixup' function
+ and then redirect to the address it returns. */
+#define TRAMPOLINE_TEMPLATE(tramp_name, fixup_name, IMB) \
+ extern void tramp_name (void); \
+ asm ( "\
+ .globl " #tramp_name " \n\
+ .ent " #tramp_name " \n\
+" #tramp_name ": \n\
+ lda $sp, -44*8($sp) \n\
+ .frame $sp, 44*8, $26 \n\
+ /* Preserve all integer registers that C normally \n\
+ doesn't. */ \n\
+ stq $26, 0*8($sp) \n\
+ stq $0, 1*8($sp) \n\
+ stq $1, 2*8($sp) \n\
+ stq $2, 3*8($sp) \n\
+ stq $3, 4*8($sp) \n\
+ stq $4, 5*8($sp) \n\
+ stq $5, 6*8($sp) \n\
+ stq $6, 7*8($sp) \n\
+ stq $7, 8*8($sp) \n\
+ stq $8, 9*8($sp) \n\
+ stq $16, 10*8($sp) \n\
+ stq $17, 11*8($sp) \n\
+ stq $18, 12*8($sp) \n\
+ stq $19, 13*8($sp) \n\
+ stq $20, 14*8($sp) \n\
+ stq $21, 15*8($sp) \n\
+ stq $22, 16*8($sp) \n\
+ stq $23, 17*8($sp) \n\
+ stq $24, 18*8($sp) \n\
+ stq $25, 19*8($sp) \n\
+ stq $29, 20*8($sp) \n\
+ stt $f0, 21*8($sp) \n\
+ stt $f1, 22*8($sp) \n\
+ stt $f10, 23*8($sp) \n\
+ stt $f11, 24*8($sp) \n\
+ stt $f12, 25*8($sp) \n\
+ stt $f13, 26*8($sp) \n\
+ stt $f14, 27*8($sp) \n\
+ stt $f15, 28*8($sp) \n\
+ stt $f16, 29*8($sp) \n\
+ stt $f17, 30*8($sp) \n\
+ stt $f18, 31*8($sp) \n\
+ stt $f19, 32*8($sp) \n\
+ stt $f20, 33*8($sp) \n\
+ stt $f21, 34*8($sp) \n\
+ stt $f22, 35*8($sp) \n\
+ stt $f23, 36*8($sp) \n\
+ stt $f24, 37*8($sp) \n\
+ stt $f25, 38*8($sp) \n\
+ stt $f26, 39*8($sp) \n\
+ stt $f27, 40*8($sp) \n\
+ stt $f28, 41*8($sp) \n\
+ stt $f29, 42*8($sp) \n\
+ stt $f30, 43*8($sp) \n\
+ .mask 0x27ff01ff, -44*8 \n\
+ .fmask 0xfffffc03, -(44-21)*8 \n\
+ /* Set up our $gp */ \n\
+ br $gp, .+4 \n\
+ ldgp $gp, 0($gp) \n\
+ .prologue 0 \n\
+ /* Set up the arguments for fixup: */ \n\
+ /* $16 = link_map out of plt0 */ \n\
+ /* $17 = offset of reloc entry = ($28 - $27 - 20) /12 * 24 */\n\
+ /* $18 = return address */ \n\
+ subq $28, $27, $17 \n\
+ ldq $16, 8($27) \n\
+ subq $17, 20, $17 \n\
+ mov $26, $18 \n\
+ addq $17, $17, $17 \n\
+ /* Do the fixup */ \n\
+ bsr $26, " #fixup_name " !samegp \n\
+ /* Move the destination address into position. */ \n\
+ mov $0, $27 \n\
+ /* Restore program registers. */ \n\
+ ldq $26, 0*8($sp) \n\
+ ldq $0, 1*8($sp) \n\
+ ldq $1, 2*8($sp) \n\
+ ldq $2, 3*8($sp) \n\
+ ldq $3, 4*8($sp) \n\
+ ldq $4, 5*8($sp) \n\
+ ldq $5, 6*8($sp) \n\
+ ldq $6, 7*8($sp) \n\
+ ldq $7, 8*8($sp) \n\
+ ldq $8, 9*8($sp) \n\
+ ldq $16, 10*8($sp) \n\
+ ldq $17, 11*8($sp) \n\
+ ldq $18, 12*8($sp) \n\
+ ldq $19, 13*8($sp) \n\
+ ldq $20, 14*8($sp) \n\
+ ldq $21, 15*8($sp) \n\
+ ldq $22, 16*8($sp) \n\
+ ldq $23, 17*8($sp) \n\
+ ldq $24, 18*8($sp) \n\
+ ldq $25, 19*8($sp) \n\
+ ldq $29, 20*8($sp) \n\
+ ldt $f0, 21*8($sp) \n\
+ ldt $f1, 22*8($sp) \n\
+ ldt $f10, 23*8($sp) \n\
+ ldt $f11, 24*8($sp) \n\
+ ldt $f12, 25*8($sp) \n\
+ ldt $f13, 26*8($sp) \n\
+ ldt $f14, 27*8($sp) \n\
+ ldt $f15, 28*8($sp) \n\
+ ldt $f16, 29*8($sp) \n\
+ ldt $f17, 30*8($sp) \n\
+ ldt $f18, 31*8($sp) \n\
+ ldt $f19, 32*8($sp) \n\
+ ldt $f20, 33*8($sp) \n\
+ ldt $f21, 34*8($sp) \n\
+ ldt $f22, 35*8($sp) \n\
+ ldt $f23, 36*8($sp) \n\
+ ldt $f24, 37*8($sp) \n\
+ ldt $f25, 38*8($sp) \n\
+ ldt $f26, 39*8($sp) \n\
+ ldt $f27, 40*8($sp) \n\
+ ldt $f28, 41*8($sp) \n\
+ ldt $f29, 42*8($sp) \n\
+ ldt $f30, 43*8($sp) \n\
+ /* Flush the Icache after having modified the .plt code. */\n\
+ " #IMB " \n\
+ /* Clean up and turn control to the destination */ \n\
+ lda $sp, 44*8($sp) \n\
+ jmp $31, ($27) \n\
+ .end " #tramp_name)
+
+#ifndef PROF
+#define ELF_MACHINE_RUNTIME_TRAMPOLINE \
+ TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup, imb); \
+ TRAMPOLINE_TEMPLATE (_dl_runtime_profile, profile_fixup, /* nop */);
+#else
+#define ELF_MACHINE_RUNTIME_TRAMPOLINE \
+ TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup, imb); \
+ strong_alias (_dl_runtime_resolve, _dl_runtime_profile);
+#endif
+
/* Initial entry point code for the dynamic linker.
The C function `_dl_start' is the real entry point;
its return value is the user program's entry point. */
@@ -252,7 +416,7 @@ $fixup_stack: \n\
/* Fix up the instructions of a PLT entry to invoke the function
rather than the dynamic linker. */
static inline Elf64_Addr
-elf_machine_fixup_plt (struct link_map *map, lookup_t t,
+elf_machine_fixup_plt (struct link_map *l, lookup_t t,
const Elf64_Rela *reloc,
Elf64_Addr *got_addr, Elf64_Addr value)
{
@@ -263,16 +427,10 @@ elf_machine_fixup_plt (struct link_map *map, lookup_t t,
/* Store the value we are going to load. */
*got_addr = value;
- /* If this binary uses the read-only secure plt format, we're done. */
- if (map->l_info[DT_ALPHA(PLTRO)])
- return value;
-
- /* Otherwise we have to modify the plt entry in place to do the branch. */
-
/* Recover the PLT entry address by calculating reloc's index into the
.rela.plt, and finding that entry in the .plt. */
- rela_plt = (const Elf64_Rela *) D_PTR (map, l_info[DT_JMPREL]);
- plte = (Elf64_Word *) (D_PTR (map, l_info[DT_PLTGOT]) + 32);
+ rela_plt = (void *) D_PTR (l, l_info[DT_JMPREL]);
+ plte = (void *) (D_PTR (l, l_info[DT_PLTGOT]) + 32);
plte += 3 * (reloc - rela_plt);
/* Find the displacement from the plt entry to the function. */
@@ -343,18 +501,13 @@ elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc,
return value + reloc->r_addend;
}
-/* Names of the architecture-specific auditing callback functions. */
-#define ARCH_LA_PLTENTER alpha_gnu_pltenter
-#define ARCH_LA_PLTEXIT alpha_gnu_pltexit
-
#endif /* !dl_machine_h */
-#ifdef RESOLVE_MAP
+#ifdef RESOLVE
/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
MAP is the object containing the reloc. */
auto inline void
-__attribute__ ((always_inline))
elf_machine_rela (struct link_map *map,
const Elf64_Rela *reloc,
const Elf64_Sym *sym,
@@ -402,16 +555,26 @@ elf_machine_rela (struct link_map *map,
return;
else
{
- struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
Elf64_Addr sym_value;
Elf64_Addr sym_raw_value;
+#if defined USE_TLS && !defined RTLD_BOOTSTRAP
+ struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
sym_raw_value = sym_value = reloc->r_addend;
- if (sym_map)
+ if (sym)
{
sym_raw_value += sym->st_value;
sym_value = sym_raw_value + sym_map->l_addr;
}
+#else
+ Elf64_Addr loadbase = RESOLVE (&sym, version, r_type);
+ sym_raw_value = sym_value = reloc->r_addend;
+ if (sym)
+ {
+ sym_raw_value += sym->st_value;
+ sym_value = sym_raw_value + loadbase;
+ }
+#endif
if (r_type == R_ALPHA_GLOB_DAT)
*reloc_addr = sym_value;
@@ -483,7 +646,6 @@ elf_machine_rela (struct link_map *map,
#define ELF_MACHINE_REL_RELATIVE 1
auto inline void
-__attribute__ ((always_inline))
elf_machine_rela_relative (Elf64_Addr l_addr, const Elf64_Rela *reloc,
void *const reloc_addr_arg)
{
@@ -500,7 +662,6 @@ elf_machine_rela_relative (Elf64_Addr l_addr, const Elf64_Rela *reloc,
}
auto inline void
-__attribute__ ((always_inline))
elf_machine_lazy_rel (struct link_map *map,
Elf64_Addr l_addr, const Elf64_Rela *reloc)
{
@@ -519,4 +680,4 @@ elf_machine_lazy_rel (struct link_map *map,
_dl_reloc_bad_type (map, r_type, 1);
}
-#endif /* RESOLVE_MAP */
+#endif /* RESOLVE */