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Diffstat (limited to 'sysdeps/alpha/dl-machine.h')
-rw-r--r-- | sysdeps/alpha/dl-machine.h | 529 |
1 files changed, 0 insertions, 529 deletions
diff --git a/sysdeps/alpha/dl-machine.h b/sysdeps/alpha/dl-machine.h deleted file mode 100644 index 7580cd29b6..0000000000 --- a/sysdeps/alpha/dl-machine.h +++ /dev/null @@ -1,529 +0,0 @@ -/* Machine-dependent ELF dynamic relocation inline functions. Alpha version. - Copyright (C) 1996-2017 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Richard Henderson <rth@tamu.edu>. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library. If not, see - <http://www.gnu.org/licenses/>. */ - -/* This was written in the absence of an ABI -- don't expect - it to remain unchanged. */ - -#ifndef dl_machine_h -#define dl_machine_h 1 - -#define ELF_MACHINE_NAME "alpha" - -#include <string.h> - - -/* Mask identifying addresses reserved for the user program, - 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) -{ - return ehdr->e_machine == EM_ALPHA; -} - -/* Return the link-time address of _DYNAMIC. The multiple-got-capable - linker no longer allocates the first .got entry for this. But not to - worry, no special tricks are needed. */ -static inline Elf64_Addr -elf_machine_dynamic (void) -{ -#ifndef NO_AXP_MULTI_GOT_LD - return (Elf64_Addr) &_DYNAMIC; -#else - register Elf64_Addr *gp __asm__ ("$29"); - return gp[-4096]; -#endif -} - -/* 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 = ˙ - return (void *)&dot - dot; -} - -/* 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) -{ - 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; - - if (__builtin_expect (profile, 0)) - { - if (secureplt) - resolve = _dl_runtime_profile_new; - else - resolve = _dl_runtime_profile_old; - - if (GLRO(dl_profile) && _dl_name_match_p (GLRO(dl_profile), map)) - { - /* This is the object we are looking for. Say that we really - want profiling and the timers are started. */ - GL(dl_profile_map) = map; - } - } - - pg->resolve = resolve; - pg->link = map; - - return lazy; -} - -/* 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. */ - -#define RTLD_START asm ("\ - .section .text \n\ - .set at \n\ - .globl _start \n\ - .ent _start \n\ -_start: \n\ - .frame $31,0,$31,0 \n\ - br $gp, 0f \n\ -0: ldgp $gp, 0($gp) \n\ - .prologue 0 \n\ - /* Pass pointer to argument block to _dl_start. */ \n\ - mov $sp, $16 \n\ - bsr $26, _dl_start !samegp \n\ - .end _start \n\ - /* FALLTHRU */ \n\ - .globl _dl_start_user \n\ - .ent _dl_start_user \n\ -_dl_start_user: \n\ - .frame $31,0,$31,0 \n\ - .prologue 0 \n\ - /* Save the user entry point address in s0. */ \n\ - mov $0, $9 \n\ - /* See if we were run as a command with the executable \n\ - file name as an extra leading argument. */ \n\ - ldah $1, _dl_skip_args($gp) !gprelhigh \n\ - ldl $1, _dl_skip_args($1) !gprellow \n\ - bne $1, $fixup_stack \n\ -$fixup_stack_ret: \n\ - /* The special initializer gets called with the stack \n\ - just as the application's entry point will see it; \n\ - it can switch stacks if it moves these contents \n\ - over. */ \n\ -" RTLD_START_SPECIAL_INIT " \n\ - /* Call _dl_init(_dl_loaded, argc, argv, envp) to run \n\ - initializers. */ \n\ - ldah $16, _rtld_local($gp) !gprelhigh \n\ - ldq $16, _rtld_local($16) !gprellow \n\ - ldq $17, 0($sp) \n\ - lda $18, 8($sp) \n\ - s8addq $17, 8, $19 \n\ - addq $19, $18, $19 \n\ - bsr $26, _dl_init !samegp \n\ - /* Pass our finalizer function to the user in $0. */ \n\ - ldah $0, _dl_fini($gp) !gprelhigh \n\ - lda $0, _dl_fini($0) !gprellow \n\ - /* Jump to the user's entry point. */ \n\ - mov $9, $27 \n\ - jmp ($9) \n\ -$fixup_stack: \n\ - /* Adjust the stack pointer to skip _dl_skip_args words.\n\ - This involves copying everything down, since the \n\ - stack pointer must always be 16-byte aligned. */ \n\ - ldah $7, __GI__dl_argv($gp) !gprelhigh \n\ - ldq $2, 0($sp) \n\ - ldq $5, __GI__dl_argv($7) !gprellow \n\ - subq $31, $1, $6 \n\ - subq $2, $1, $2 \n\ - s8addq $6, $5, $5 \n\ - mov $sp, $4 \n\ - s8addq $1, $sp, $3 \n\ - stq $2, 0($sp) \n\ - stq $5, __GI__dl_argv($7) !gprellow \n\ - /* Copy down argv. */ \n\ -0: ldq $5, 8($3) \n\ - addq $4, 8, $4 \n\ - addq $3, 8, $3 \n\ - stq $5, 0($4) \n\ - bne $5, 0b \n\ - /* Copy down envp. */ \n\ -1: ldq $5, 8($3) \n\ - addq $4, 8, $4 \n\ - addq $3, 8, $3 \n\ - stq $5, 0($4) \n\ - bne $5, 1b \n\ - /* Copy down auxiliary table. */ \n\ -2: ldq $5, 8($3) \n\ - ldq $6, 16($3) \n\ - addq $4, 16, $4 \n\ - addq $3, 16, $3 \n\ - stq $5, -8($4) \n\ - stq $6, 0($4) \n\ - bne $5, 2b \n\ - br $fixup_stack_ret \n\ - .end _dl_start_user \n\ - .set noat \n\ -.previous"); - -#ifndef RTLD_START_SPECIAL_INIT -#define RTLD_START_SPECIAL_INIT /* nothing */ -#endif - -/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry - or TLS variables, so undefined references should not be allowed - to define the value. - - ELF_RTYPE_CLASS_COPY iff TYPE should not be allowed to resolve - to one of the main executable's symbols, as for a COPY reloc. - This is unused on Alpha. */ - -# define elf_machine_type_class(type) \ - (((type) == R_ALPHA_JMP_SLOT \ - || (type) == R_ALPHA_DTPMOD64 \ - || (type) == R_ALPHA_DTPREL64 \ - || (type) == R_ALPHA_TPREL64) * ELF_RTYPE_CLASS_PLT) - -/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */ -#define ELF_MACHINE_JMP_SLOT R_ALPHA_JMP_SLOT - -/* The alpha never uses Elf64_Rel relocations. */ -#define ELF_MACHINE_NO_REL 1 -#define ELF_MACHINE_NO_RELA 0 - -/* We define an initialization functions. This is called very early in - * _dl_sysdep_start. */ -#define DL_PLATFORM_INIT dl_platform_init () - -static inline void __attribute__ ((unused)) -dl_platform_init (void) -{ - if (GLRO(dl_platform) != NULL && *GLRO(dl_platform) == '\0') - /* Avoid an empty string which would disturb us. */ - GLRO(dl_platform) = NULL; -} - -/* 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, - const Elf64_Rela *reloc, - Elf64_Addr *got_addr, Elf64_Addr value) -{ - const Elf64_Rela *rela_plt; - Elf64_Word *plte; - long int edisp; - - /* 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); - plte += 3 * (reloc - rela_plt); - - /* Find the displacement from the plt entry to the function. */ - edisp = (long int) (value - (Elf64_Addr)&plte[3]) / 4; - - if (edisp >= -0x100000 && edisp < 0x100000) - { - /* If we are in range, use br to perfect branch prediction and - elide the dependency on the address load. This case happens, - e.g., when a shared library call is resolved to the same library. */ - - int hi, lo; - hi = value - (Elf64_Addr)&plte[0]; - lo = (short int) hi; - hi = (hi - lo) >> 16; - - /* Emit "lda $27,lo($27)" */ - plte[1] = 0x237b0000 | (lo & 0xffff); - - /* Emit "br $31,function" */ - plte[2] = 0xc3e00000 | (edisp & 0x1fffff); - - /* Think about thread-safety -- the previous instructions must be - committed to memory before the first is overwritten. */ - __asm__ __volatile__("wmb" : : : "memory"); - - /* Emit "ldah $27,hi($27)" */ - plte[0] = 0x277b0000 | (hi & 0xffff); - } - else - { - /* Don't bother with the hint since we already know the hint is - wrong. Eliding it prevents the wrong page from getting pulled - into the cache. */ - - int hi, lo; - hi = (Elf64_Addr)got_addr - (Elf64_Addr)&plte[0]; - lo = (short)hi; - hi = (hi - lo) >> 16; - - /* Emit "ldq $27,lo($27)" */ - plte[1] = 0xa77b0000 | (lo & 0xffff); - - /* Emit "jmp $31,($27)" */ - plte[2] = 0x6bfb0000; - - /* Think about thread-safety -- the previous instructions must be - committed to memory before the first is overwritten. */ - __asm__ __volatile__("wmb" : : : "memory"); - - /* Emit "ldah $27,hi($27)" */ - plte[0] = 0x277b0000 | (hi & 0xffff); - } - - /* At this point, if we've been doing runtime resolution, Icache is dirty. - This will be taken care of in _dl_runtime_resolve. If instead we are - doing this as part of non-lazy startup relocation, that bit of code - hasn't made it into Icache yet, so there's nothing to clean up. */ - - return value; -} - -/* Return the final value of a plt relocation. */ -static inline Elf64_Addr -elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc, - Elf64_Addr value) -{ - 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 - -/* 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, - const struct r_found_version *version, - void *const reloc_addr_arg, - int skip_ifunc) -{ - Elf64_Addr *const reloc_addr = reloc_addr_arg; - unsigned long int const r_type = ELF64_R_TYPE (reloc->r_info); - -#if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC && !defined SHARED - /* This is defined in rtld.c, but nowhere in the static libc.a; make the - reference weak so static programs can still link. This declaration - cannot be done when compiling rtld.c (i.e. #ifdef RTLD_BOOTSTRAP) - because rtld.c contains the common defn for _dl_rtld_map, which is - incompatible with a weak decl in the same file. */ - weak_extern (_dl_rtld_map); -#endif - - /* We cannot use a switch here because we cannot locate the switch - jump table until we've self-relocated. */ - -#if !defined RTLD_BOOTSTRAP || !defined HAVE_Z_COMBRELOC - if (__builtin_expect (r_type == R_ALPHA_RELATIVE, 0)) - { -# if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC - /* Already done in dynamic linker. */ - if (map != &GL(dl_rtld_map)) -# endif - { - /* XXX Make some timings. Maybe it's preferable to test for - unaligned access and only do it the complex way if necessary. */ - Elf64_Addr reloc_addr_val; - - /* Load value without causing unaligned trap. */ - memcpy (&reloc_addr_val, reloc_addr_arg, 8); - reloc_addr_val += map->l_addr; - - /* Store value without causing unaligned trap. */ - memcpy (reloc_addr_arg, &reloc_addr_val, 8); - } - } - else -#endif - if (__builtin_expect (r_type == R_ALPHA_NONE, 0)) - return; - else - { - struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type); - Elf64_Addr sym_value; - Elf64_Addr sym_raw_value; - - sym_raw_value = sym_value = reloc->r_addend; - if (sym_map) - { - sym_raw_value += sym->st_value; - sym_value = sym_raw_value + sym_map->l_addr; - } - - if (r_type == R_ALPHA_GLOB_DAT) - *reloc_addr = sym_value; -#ifdef RESOLVE_CONFLICT_FIND_MAP - /* In .gnu.conflict section, R_ALPHA_JMP_SLOT relocations have - R_ALPHA_JMP_SLOT in lower 8 bits and the remaining 24 bits - are .rela.plt index. */ - else if ((r_type & 0xff) == R_ALPHA_JMP_SLOT) - { - /* elf_machine_fixup_plt needs the map reloc_addr points into, - while in _dl_resolve_conflicts map is _dl_loaded. */ - RESOLVE_CONFLICT_FIND_MAP (map, reloc_addr); - reloc = ((const Elf64_Rela *) D_PTR (map, l_info[DT_JMPREL])) - + (r_type >> 8); - elf_machine_fixup_plt (map, 0, reloc, reloc_addr, sym_value); - } -#else - else if (r_type == R_ALPHA_JMP_SLOT) - elf_machine_fixup_plt (map, 0, reloc, reloc_addr, sym_value); -#endif -#ifndef RTLD_BOOTSTRAP - else if (r_type == R_ALPHA_REFQUAD) - { - /* Store value without causing unaligned trap. */ - memcpy (reloc_addr_arg, &sym_value, 8); - } -#endif - else if (r_type == R_ALPHA_DTPMOD64) - { -# ifdef RTLD_BOOTSTRAP - /* During startup the dynamic linker is always index 1. */ - *reloc_addr = 1; -# else - /* Get the information from the link map returned by the - resolv function. */ - if (sym_map != NULL) - *reloc_addr = sym_map->l_tls_modid; -# endif - } - else if (r_type == R_ALPHA_DTPREL64) - { -# ifndef RTLD_BOOTSTRAP - /* During relocation all TLS symbols are defined and used. - Therefore the offset is already correct. */ - *reloc_addr = sym_raw_value; -# endif - } - else if (r_type == R_ALPHA_TPREL64) - { -# ifdef RTLD_BOOTSTRAP - *reloc_addr = sym_raw_value + map->l_tls_offset; -# else - if (sym_map) - { - CHECK_STATIC_TLS (map, sym_map); - *reloc_addr = sym_raw_value + sym_map->l_tls_offset; - } -# endif - } - else - _dl_reloc_bad_type (map, r_type, 0); - } -} - -/* Let do-rel.h know that on Alpha if l_addr is 0, all RELATIVE relocs - can be skipped. */ -#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) -{ - /* XXX Make some timings. Maybe it's preferable to test for - unaligned access and only do it the complex way if necessary. */ - Elf64_Addr reloc_addr_val; - - /* Load value without causing unaligned trap. */ - memcpy (&reloc_addr_val, reloc_addr_arg, 8); - reloc_addr_val += l_addr; - - /* Store value without causing unaligned trap. */ - memcpy (reloc_addr_arg, &reloc_addr_val, 8); -} - -auto inline void -__attribute__ ((always_inline)) -elf_machine_lazy_rel (struct link_map *map, - Elf64_Addr l_addr, const Elf64_Rela *reloc, - int skip_ifunc) -{ - Elf64_Addr * const reloc_addr = (void *)(l_addr + reloc->r_offset); - unsigned long int const r_type = ELF64_R_TYPE (reloc->r_info); - - if (r_type == R_ALPHA_JMP_SLOT) - { - /* Perform a RELATIVE reloc on the .got entry that transfers - to the .plt. */ - *reloc_addr += l_addr; - } - else if (r_type == R_ALPHA_NONE) - return; - else - _dl_reloc_bad_type (map, r_type, 1); -} - -#endif /* RESOLVE_MAP */ |