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authorAlexandre Oliva <aoliva@redhat.com>2003-03-14 08:43:13 +0000
committerAlexandre Oliva <aoliva@redhat.com>2003-03-14 08:43:13 +0000
commit365eccdb099f7cff2fdc589bef7be7806a4bc9c7 (patch)
tree6892ddc3a1acb68b3491780b29f851b3cdbe53e0 /sysdeps/mips/dl-machine.h
parentd4c803f80a95075271defb43f91e193fd94f1f45 (diff)
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* sysdeps/mips/dl-machine.h: Include sys/asm.h. (elf_machine_matches_host): Prevent linking of o32 and n32 together. (elf_machine_dynamic): Document assumption on $gp. (STRINGXP, STRINGXV, STRINGV_): New macros. (elf_machine_load_address): Use them to stringize PTR_LA and PTR_SUBU. (ELF_DL_FRAME_SIZE, ELF_DL_SAVE_ARG_REGS, ELF_DL_RESTORE_ARG_REGS, IFABIO32): New macros used in... (_dl_runtime_resolve): Adjust it for all 3 ABIs. (__dl_runtime_resolve): Cast the symtab initializer to the right type. (RTLD_START): Use it. Adjust it for all 3 ABIs. (elf_machine_rel): Mark as always_inline in RTLD_BOOTSTRAP. Handle 64-bit R_MIPS_REL composite relocation and accept R_MIPS_64 relocations to shift addend size to 64 bits. Document assumption regarding local GOT entries. Document backward-compatibility departing from the ABI behavior in applying relocations that reference section symbols, no longer used. Support relocations to mis-aligned offsets. * sysdeps/mips/mips64/dl-machine.h: Deleted, obsolete.
* sysdeps/mips/dl-machine.h: Include sys/asm.h. (elf_machine_matches_host): Prevent linking of o32 and n32 together. (elf_machine_dynamic): Document assumption on $gp. (STRINGXP, STRINGXV, STRINGV_): New macros. (elf_machine_load_address): Use them to stringize PTR_LA and PTR_SUBU. (ELF_DL_FRAME_SIZE, ELF_DL_SAVE_ARG_REGS, ELF_DL_RESTORE_ARG_REGS, IFABIO32): New macros used in... (_dl_runtime_resolve): Adjust it for all 3 ABIs. (__dl_runtime_resolve): Cast the symtab initializer to the right type. (RTLD_START): Use it. Adjust it for all 3 ABIs. (elf_machine_rel): Mark as always_inline in RTLD_BOOTSTRAP. Handle 64-bit R_MIPS_REL composite relocation and accept R_MIPS_64 relocations to shift addend size to 64 bits. Document assumption regarding local GOT entries. Document backward-compatibility departing from the ABI behavior in applying relocations that reference section symbols, no longer used. Support relocations to mis-aligned offsets. * sysdeps/mips/mips64/dl-machine.h: Deleted, obsolete.
Diffstat (limited to 'sysdeps/mips/dl-machine.h')
-rw-r--r--sysdeps/mips/dl-machine.h221
1 files changed, 159 insertions, 62 deletions
diff --git a/sysdeps/mips/dl-machine.h b/sysdeps/mips/dl-machine.h
index c4864c21d2..62c3f20736 100644
--- a/sysdeps/mips/dl-machine.h
+++ b/sysdeps/mips/dl-machine.h
@@ -32,6 +32,8 @@
#error ENTRY_POINT needs to be defined for MIPS.
#endif
+#include <sys/asm.h>
+
/* The offset of gp from GOT might be system-dependent. It's set by
ld. The same value is also */
#define OFFSET_GP_GOT 0x7ff0
@@ -72,6 +74,13 @@ do { if ((l)->l_info[DT_MIPS (RLD_MAP)]) \
static inline int __attribute_used__
elf_machine_matches_host (const ElfW(Ehdr) *ehdr)
{
+#if _MIPS_SIM == _MIPS_SIM_ABI32 || _MIPS_SIM == _MIPS_SIM_NABI32
+ /* Don't link o32 and n32 together. */
+ if (((ehdr->e_flags & EF_MIPS_ABI2) != 0)
+ != (_MIPS_SIM != _MIPS_SIM_ABI32))
+ return 0;
+#endif
+
switch (ehdr->e_machine)
{
case EM_MIPS:
@@ -91,7 +100,7 @@ elf_mips_got_from_gpreg (ElfW(Addr) gpreg)
/* Return the link-time address of _DYNAMIC. Conveniently, this is the
first element of the GOT. This must be inlined in a function which
- uses global data. */
+ uses global data. We assume its $gp points to the primary GOT. */
static inline ElfW(Addr)
elf_machine_dynamic (void)
{
@@ -99,6 +108,9 @@ elf_machine_dynamic (void)
return *elf_mips_got_from_gpreg (gp);
}
+#define STRINGXP(X) __STRING(X)
+#define STRINGXV(X) STRINGV_(X)
+#define STRINGV_(...) # __VA_ARGS__
/* Return the run-time load address of the shared object. */
static inline ElfW(Addr)
@@ -106,10 +118,10 @@ elf_machine_load_address (void)
{
ElfW(Addr) addr;
asm (" .set noreorder\n"
- " la %0, here\n"
- " bltzal $0, here\n"
+ " " STRINGXP (PTR_LA) " %0, 0f\n"
+ " bltzal $0, 0f\n"
" nop\n"
- "here: subu %0, $31, %0\n"
+ "0: " STRINGXP (PTR_SUBU) " %0, $31, %0\n"
" .set reorder\n"
: "=r" (addr)
: /* No inputs */
@@ -242,6 +254,55 @@ elf_machine_runtime_link_map (ElfW(Addr) gpreg, ElfW(Addr) stub_pc)
return NULL;
}
+#if _MIPS_SIM == _MIPS_SIM_ABI32
+#define ELF_DL_FRAME_SIZE 40
+
+#define ELF_DL_SAVE_ARG_REGS "\
+ sw $15, 36($29)\n \
+ sw $4, 16($29)\n \
+ sw $5, 20($29)\n \
+ sw $6, 24($29)\n \
+ sw $7, 28($29)\n \
+"
+
+#define ELF_DL_RESTORE_ARG_REGS "\
+ lw $31, 36($29)\n \
+ lw $4, 16($29)\n \
+ lw $5, 20($29)\n \
+ lw $6, 24($29)\n \
+ lw $7, 28($29)\n \
+"
+
+#define IFABIO32(X) X
+
+#else /* _MIPS_SIM == _MIPS_SIM_NABI32 || _MIPS_SIM == _MIPS_SIM_ABI64 */
+
+#define ELF_DL_FRAME_SIZE 64
+
+#define ELF_DL_SAVE_ARG_REGS "\
+ sd $15, 56($29)\n \
+ sd $4, 8($29)\n \
+ sd $5, 16($29)\n \
+ sd $6, 24($29)\n \
+ sd $7, 32($29)\n \
+ sd $8, 40($29)\n \
+ sd $9, 48($29)\n \
+"
+
+#define ELF_DL_RESTORE_ARG_REGS "\
+ ld $31, 56($29)\n \
+ ld $4, 8($29)\n \
+ ld $5, 16($29)\n \
+ ld $6, 24($29)\n \
+ ld $7, 32($29)\n \
+ ld $8, 40($29)\n \
+ ld $9, 48($29)\n \
+"
+
+#define IFABIO32(X)
+
+#endif
+
/* Define mips specific runtime resolver. The function __dl_runtime_resolve
is called from assembler function _dl_runtime_resolve which converts
special argument registers t7 ($15) and t8 ($24):
@@ -272,9 +333,8 @@ __dl_runtime_resolve (ElfW(Word) sym_index, \
{ \
struct link_map *l = elf_machine_runtime_link_map (old_gpreg, stub_pc); \
const ElfW(Sym) *const symtab \
- = (const void *) D_PTR (l, l_info[DT_SYMTAB]); \
- const char *strtab \
- = (const void *) D_PTR (l, l_info[DT_STRTAB]); \
+ = (const ElfW(Sym) *) D_PTR (l, l_info[DT_SYMTAB]); \
+ const char *strtab = (const void *) D_PTR (l, l_info[DT_STRTAB]); \
ElfW(Addr) *got \
= (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]); \
const ElfW(Word) local_gotno \
@@ -333,36 +393,30 @@ asm ("\n \
.type _dl_runtime_resolve,@function\n \
.ent _dl_runtime_resolve\n \
_dl_runtime_resolve:\n \
- .frame $29, 40, $31\n \
+ .frame $29, " STRINGXP(ELF_DL_FRAME_SIZE) ", $31\n \
.set noreorder\n \
# Save GP.\n \
move $3, $28\n \
+ # Save arguments and sp value in stack.\n \
+ " STRINGXP(PTR_SUBIU) " $29, " STRINGXP(ELF_DL_FRAME_SIZE) "\n \
# Modify t9 ($25) so as to point .cpload instruction.\n \
- addu $25, 8\n \
+ " IFABIO32(STRINGXP(PTR_ADDIU) " $25, 12\n") " \
# Compute GP.\n \
- .cpload $25\n \
+ " STRINGXP(SETUP_GP) "\n \
+ " STRINGXV(SETUP_GP64 (0, _dl_runtime_resolve)) "\n \
.set reorder\n \
# Save slot call pc.\n \
move $2, $31\n \
- # Save arguments and sp value in stack.\n \
- subu $29, 40\n \
- .cprestore 32\n \
- sw $15, 36($29)\n \
- sw $4, 16($29)\n \
- sw $5, 20($29)\n \
- sw $6, 24($29)\n \
- sw $7, 28($29)\n \
+ " IFABIO32(STRINGXP(CPRESTORE(32))) "\n \
+ " ELF_DL_SAVE_ARG_REGS " \
move $4, $24\n \
move $5, $15\n \
move $6, $3\n \
move $7, $2\n \
jal __dl_runtime_resolve\n \
- lw $31, 36($29)\n \
- lw $4, 16($29)\n \
- lw $5, 20($29)\n \
- lw $6, 24($29)\n \
- lw $7, 28($29)\n \
- addu $29, 40\n \
+ " ELF_DL_RESTORE_ARG_REGS " \
+ " STRINGXP(RESTORE_GP64) "\n \
+ " STRINGXP(PTR_ADDIU) " $29, " STRINGXP(ELF_DL_FRAME_SIZE) "\n \
move $25, $2\n \
jr $25\n \
.end _dl_runtime_resolve\n \
@@ -374,7 +428,6 @@ _dl_runtime_resolve:\n \
#define ELF_MACHINE_USER_ADDRESS_MASK 0x80000000UL
-
/* 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.
@@ -392,71 +445,71 @@ _dl_runtime_resolve:\n \
#define RTLD_START asm (\
".text\n"\
- _RTLD_PROLOGUE(ENTRY_POINT)\
- ".set noreorder\n\
- bltzal $0, 0f\n\
- nop\n\
-0: .cpload $31\n\
- .set reorder\n\
+ _RTLD_PROLOGUE(ENTRY_POINT) "\
+ " STRINGXV(SETUP_GPX($25)) "\n\
+ " STRINGXV(SETUP_GPX64($18,$25)) "\n\
# i386 ABI book says that the first entry of GOT holds\n\
# the address of the dynamic structure. Though MIPS ABI\n\
# doesn't say nothing about this, I emulate this here.\n\
- la $4, _DYNAMIC\n\
+ " STRINGXP(PTR_LA) " $4, _DYNAMIC\n\
# Subtract OFFSET_GP_GOT\n\
- sw $4, -0x7ff0($28)\n\
+ " STRINGXP(PTR_S) " $4, -0x7ff0($28)\n\
move $4, $29\n\
- subu $29, 16\n\
+ " STRINGXP(PTR_SUBIU) " $29, 16\n\
\n\
- la $8, coff\n\
- bltzal $8, coff\n\
-coff: subu $8, $31, $8\n\
+ " STRINGXP(PTR_LA) " $8, .Lcoff\n\
+ bltzal $8, .Lcoff\n\
+.Lcoff: " STRINGXP(PTR_SUBU) " $8, $31, $8\n\
\n\
- la $25, _dl_start\n\
- addu $25, $8\n\
+ " STRINGXP(PTR_LA) " $25, _dl_start\n\
+ " STRINGXP(PTR_ADDU) " $25, $8\n\
jalr $25\n\
\n\
- addiu $29, 16\n\
+ " STRINGXP(PTR_ADDIU) " $29, 16\n\
# Get the value of label '_dl_start_user' in t9 ($25).\n\
- la $25, _dl_start_user\n\
+ " STRINGXP(PTR_LA) " $25, _dl_start_user\n\
.globl _dl_start_user\n\
+ .type _dl_start_user,@function\n\
+ .ent _dl_start_user\n\
_dl_start_user:\n\
- .set noreorder\n\
- .cpload $25\n\
- .set reorder\n\
+ " STRINGXP(SETUP_GP) "\n\
+ " STRINGXV(SETUP_GP64($18,_dl_start_user)) "\n\
move $16, $28\n\
# Save the user entry point address in a saved register.\n\
move $17, $2\n\
# Store the highest stack address\n\
- sw $29, __libc_stack_end\n\
+ " STRINGXP(PTR_S) " $29, __libc_stack_end\n\
# See if we were run as a command with the executable file\n\
# name as an extra leading argument.\n\
lw $2, _dl_skip_args\n\
beq $2, $0, 1f\n\
# Load the original argument count.\n\
- lw $4, 0($29)\n\
+ " STRINGXP(PTR_L) " $4, 0($29)\n\
# Subtract _dl_skip_args from it.\n\
subu $4, $2\n\
# Adjust the stack pointer to skip _dl_skip_args words.\n\
- sll $2, 2\n\
- addu $29, $2\n\
+ sll $2, " STRINGXP (PTRLOG) "\n\
+ " STRINGXP(PTR_ADDU) " $29, $2\n\
# Save back the modified argument count.\n\
- sw $4, 0($29)\n\
+ " STRINGXP(PTR_S) " $4, 0($29)\n\
1: # Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env) \n\
- lw $4, _rtld_local\n\
- lw $5, 0($29)\n\
- la $6, 4($29)\n\
- sll $7, $5, 2\n\
- addu $7, $7, $6\n\
- addu $7, $7, 4\n\
- subu $29, 16\n\
+ " STRINGXP(PTR_L) " $4, _rtld_local\n\
+ " STRINGXP(PTR_L) /* or lw??? fixme */ " $5, 0($29)\n\
+ " STRINGXP(PTR_LA) " $6, " STRINGXP (PTRSIZE) "($29)\n\
+ sll $7, $5, " STRINGXP (PTRLOG) "\n\
+ " STRINGXP(PTR_ADDU) " $7, $7, $6\n\
+ " STRINGXP(PTR_ADDU) " $7, $7, " STRINGXP (PTRSIZE) " \n\
+ " STRINGXP(PTR_SUBIU) " $29, 32\n\
+ " STRINGXP(SAVE_GP(16)) "\n\
# Call the function to run the initializers.\n\
jal _dl_init_internal\n\
- addiu $29, 16\n\
+ " STRINGXP(PTR_ADDIU) " $29, 32\n\
# Pass our finalizer function to the user in $2 as per ELF ABI.\n\
- la $2, _dl_fini\n\
+ " STRINGXP(PTR_LA) " $2, _dl_fini\n\
# Jump to the user entry point.\n\
move $25, $17\n\
- jr $25\n\t"\
+ jr $25\n\
+ .end _dl_start_user\n\t"\
_RTLD_EPILOGUE(ENTRY_POINT)\
".previous"\
);
@@ -472,6 +525,9 @@ _dl_start_user:\n\
MAP is the object containing the reloc. */
static inline void
+#ifdef RTLD_BOOTSTRAP
+ __attribute__ ((always_inline))
+#endif
elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc,
const ElfW(Sym) *sym, const struct r_found_version *version,
ElfW(Addr) *const reloc_addr)
@@ -490,9 +546,19 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc,
switch (r_type)
{
+#if _MIPS_SIM == _MIPS_SIM_ABI64
+ case (R_MIPS_64 << 8) | R_MIPS_REL32:
+#else
case R_MIPS_REL32:
+#endif
{
int symidx = ELFW(R_SYM) (reloc->r_info);
+ ElfW(Addr) reloc_value;
+
+ /* Support relocations on mis-aligned offsets. Should we ever
+ implement RELA, this should be replaced with an assignment
+ from reloc->r_addend. */
+ __builtin_memcpy (&reloc_value, reloc_addr, sizeof (reloc_value));
if (symidx)
{
@@ -501,10 +567,25 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc,
if (symidx < gotsym)
{
+ /* This wouldn't work for a symbol imported from other
+ libraries for which there's no GOT entry, but MIPS
+ requires every symbol referenced in a dynamic
+ relocation to have a GOT entry in the primary GOT,
+ so we only get here for locally-defined symbols.
+ For section symbols, we should *NOT* be adding
+ sym->st_value (per the definition of the meaning of
+ S in reloc expressions in the ELF64 MIPS ABI),
+ since it should have already been added to
+ reloc_value by the linker, but older versions of
+ GNU ld didn't add it, and newer versions don't emit
+ useless relocations to section symbols any more, so
+ it is safe to keep on adding sym->st_value, even
+ though it's not ABI compliant. Some day we should
+ bite the bullet and stop doing this. */
#ifndef RTLD_BOOTSTRAP
if (map != &GL(dl_rtld_map))
#endif
- *reloc_addr += sym->st_value + map->l_addr;
+ reloc_value += sym->st_value + map->l_addr;
}
else
{
@@ -515,7 +596,7 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc,
= (const ElfW(Word))
map->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val;
- *reloc_addr += got[symidx + local_gotno - gotsym];
+ reloc_value += got[symidx + local_gotno - gotsym];
#endif
}
}
@@ -523,11 +604,27 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc,
#ifndef RTLD_BOOTSTRAP
if (map != &GL(dl_rtld_map))
#endif
- *reloc_addr += map->l_addr;
+ reloc_value += map->l_addr;
+
+ __builtin_memcpy (reloc_addr, &reloc_value, sizeof (reloc_value));
}
break;
case R_MIPS_NONE: /* Alright, Wilbur. */
break;
+#if _MIPS_SIM == _MIPS_SIM_ABI64
+ case R_MIPS_64:
+ /* For full compliance with the ELF64 ABI, one must precede the
+ _REL32/_64 pair of relocations with a _64 relocation, such
+ that the in-place addend is read as a 64-bit value. IRIX
+ didn't pick up on this requirement, so we treat the
+ _REL32/_64 relocation as a 64-bit relocation even if it's by
+ itself. For ABI compliance, we ignore such _64 dummy
+ relocations. For RELA, this may be simply removed, since
+ it's totally unnecessary. */
+ if (ELFW(R_SYM) (reloc->r_info) == 0)
+ break;
+ /* Fall through. */
+#endif
default:
_dl_reloc_bad_type (map, r_type, 0);
break;