--- /dev/null
+/* Machine-dependent ELF dynamic relocation inline functions. m68k version.
+Copyright (C) 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#define ELF_MACHINE_NAME "m68k"
+
+#include <assert.h>
+#include <string.h>
+#include <link.h>
+
+
+/* Return nonzero iff E_MACHINE is compatible with the running host. */
+static inline int
+elf_machine_matches_host (Elf32_Half e_machine)
+{
+ switch (e_machine)
+ {
+ case EM_68K:
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+
+/* Return the run-time address of the _GLOBAL_OFFSET_TABLE_.
+ Must be inlined in a function which uses global data. */
+static inline Elf32_Addr *
+elf_machine_got (void)
+{
+ register Elf32_Addr *got asm ("%a5");
+ return got;
+}
+
+
+/* Return the run-time load address of the shared object. */
+static inline Elf32_Addr
+elf_machine_load_address (void)
+{
+ ...
+}
+
+/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
+ MAP is the object containing the reloc. */
+
+static inline void
+elf_machine_rela (struct link_map *map,
+ const Elf32_Rela *reloc,
+ Elf32_Addr sym_loadaddr, const Elf32_Sym *sym)
+{
+ Elf32_Addr *const reloc_addr = (void *) (map->l_addr + reloc->r_offset);
+ const Elf32_Addr sym_value = sym ? sym_loadaddr + sym->st_value : 0;
+
+ switch (ELF32_R_TYPE (reloc->r_info))
+ {
+ case R_68K_COPY:
+ memcpy (reloc_addr, (void *) sym_value, sym->st_size);
+ break;
+ case R_68K_GLOB_DAT:
+ case R_68K_JMP_SLOT:
+ *reloc_addr = sym_value;
+ break;
+ case R_68K_8:
+ *(char *) reloc_addr = sym_value + reloc->r_addend;
+ break;
+ case R_68K_16:
+ *(short *) reloc_addr = sym_value + reloc->r_addend;
+ break;
+ case R_68K_32:
+ *reloc_addr = sym_value + reloc->r_addend;
+ break;
+ case R_68K_RELATIVE:
+ *reloc_addr = map->l_addr + reloc->r_addend;
+ break;
+ case R_68K_PC8:
+ *(char *) reloc_addr = (sym_value + reloc->r_addend
+ - (Elf32_Addr) reloc_addr);
+ break;
+ case R_68K_PC16:
+ *(short *) reloc_addr = (sym_value + reloc->r_addend
+ - (Elf32_Addr) reloc_addr);
+ break;
+ case R_68K_PC32:
+ *reloc_addr = sym_value + reloc->r_addend - (Elf32_Addr) reloc_addr;
+ break;
+ case R_68K_NONE: /* Alright, Wilbur. */
+ break;
+ default:
+ assert (! "unexpected dynamic reloc type");
+ break;
+ }
+}
+
+static inline void
+elf_machine_lazy_rel (struct link_map *map, const Elf32_Rela *reloc)
+{
+ Elf32_Addr *const reloc_addr = (void *) (map->l_addr + reloc->r_offset);
+ switch (ELF32_R_TYPE (reloc->r_info))
+ {
+ case R_68K_NONE:
+ break;
+ case R_68K_JMP_SLOT:
+ *reloc_addr += map->l_addr;
+ break;
+ default:
+ assert (! "unexpected PLT reloc type");
+ break;
+ }
+}
+
+/* The m68k never uses Elf32_Rel relocations. */
+#define ELF_MACHINE_NO_REL 1
+
+
+/* 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 void
+elf_machine_runtime_setup (struct link_map *l, int lazy)
+{
+ Elf32_Addr *got;
+ extern void _dl_runtime_resolve (Elf32_Word);
+
+ if (l->l_info[DT_JMPREL] && lazy)
+ {
+ /* The GOT entries for functions in the PLT have not yet been
+ filled in. Their initial contents will arrange when called
+ to push an offset into the .rela.plt section, push
+ _GLOBAL_OFFSET_TABLE_[1], and then jump to
+ _GLOBAL_OFFSET_TABLE_[2]. */
+ got = (Elf32_Addr *) (l->l_addr + l->l_info[DT_PLTGOT]->d_un.d_ptr);
+ got[1] = (Elf32_Addr) l; /* Identify this shared object. */
+ /* This function will get called to fix up the GOT entry
+ indicated by the offset on the stack, and then jump to the
+ resolved address. */
+ got[2] = (Elf32_Addr) &_dl_runtime_resolve;
+ }
+
+ /* This code is used in dl-runtime.c to call the `fixup' function
+ and then redirect to the address it returns. */
+#define ELF_MACHINE_RUNTIME_TRAMPOLINE asm ("\
+| Trampoline for _dl_runtime_resolver
+ .globl _dl_runtime_resolve
+ .type _dl_runtime_resolve, @function
+_dl_runtime_resolve:
+ | Save %a0 (struct return address).
+ move.l %a0, -(%sp)
+ | Call the real address resolver.
+ bsr.l fixup
+ | Restore register %a0.
+ move.l (%sp)+, %a0
+ | Pop parameters
+ addq.l #8, %sp
+ | Call real function.
+ jmp (%d0)
+ .size _dl_runtime_resolve, . - _dl_runtime_resolve
+");
+#define ELF_MACHINE_RUNTIME_FIXUP_ARGS long int save_a0
+}
+
+
+/* Mask identifying addresses reserved for the user program,
+ where the dynamic linker should not map anything. */
+#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. */
+
+#define RTLD_START asm ("\
+.text
+.globl _start
+.globl _dl_start_user
+_start:
+ jbsr _dl_start
+_dl_start_user:
+ | Save the user entry point address in %a4.
+ move.l %d0, %a4
+ | Point %a5 at the GOT.
+ lea _GLOBAL_OFFSET_TABLE_@GOTPC(%pc), %a5
+ | See if we were run as a command with the executable file
+ | name as an extra leading argument.
+ move.l ([_dl_skip_args@GOT, %a5]), %d0
+ jeq 0f
+ | Pop the original argument count
+ move.l (%sp)+, %d1
+ | Subtract _dl_skip_args from it.
+ sub.l %d0, %d1
+ | Adjust the stack pointer to skip _dl_skip_args words.
+ lea (%sp, %d0*4), %sp
+ | Push back the modified argument count.
+ move.l %d1, -(%sp)
+ | Call _dl_init_next to return the address of an initializer
+ | function to run.
+0: bsr.l _dl_init_next@PLTPC
+ | Check for zero return, when out of initializers.
+ tst.l %d0
+ jeq 1f
+ | Call the shared object initializer function.
+ | NOTE: We depend only on the registers (%a4 and %a5)
+ | and the return address pushed by this call;
+ | the initializer is called with the stack just
+ | as it appears on entry, and it is free to move
+ | the stack around, as long as it winds up jumping to
+ | the return address on the top of the stack.
+ move.l %d0, %a0
+ jsr (%a0)
+ | Loop to call _dl_init_next for the next initializer.
+ jra 0b
+1: | Pass our finalizer function to the user in %a1.
+ move.l _dl_fini@GOT(%a5), %a1
+ | Initialize %fp with the stack pointer.
+ move.l %sp, %fp
+ | Jump to the user's entry point.
+ jmp (%a4)");
--- /dev/null
+/* Startup code compliant to the ELF m68k ABI.
+Copyright (C) 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+/* This is the canonical entry point, usually the first thing in the text
+ segment. The SVR4/m68k ABI says that when the entry point runs,
+ most registers' values are unspecified, except for:
+
+ %a1 Contains a function pointer to be registered with `atexit'.
+ This is how the dynamic linker arranges to have DT_FINI
+ functions called for shared libraries that have been loaded
+ before this code runs.
+
+ %sp The stack contains the arguments and environment:
+ 0(%sp) argc
+ 4(%sp) argv[0]
+ ...
+ (4*argc)(%sp) NULL
+ (4*(argc+1))(%sp) envp[0]
+ ...
+ NULL
+*/
+
+ .text
+ .globl _start
+_start:
+ /* Clear the frame pointer. The ABI suggests this be done, to mark
+ the outermost frame obviously. */
+ sub.l %fp, %fp
+
+ /* %a1 contains the address of the shared library termination
+ function, which we will register with `atexit' to be called by
+ `exit'. */
+ tstl %a1
+ jbeq 1f
+ move.l %a1, -(%sp)
+ jbsr atexit
+ addql #4, %sp
+1:
+
+ /* Do essential libc initialization. In statically linked
+ programs under the GNU Hurd, this is what sets up the
+ arguments on the stack for the code below. */
+ jbsr __libc_init_first
+
+ /* Extract the arguments and environment as encoded on the stack
+ and set up the arguments for `main': argc, argv, envp. */
+ move.l (%sp)+, %d0 /* Pop the argument count. */
+ lea (4,%sp,%d0*4), %a0 /* envp = &argv[argc + 1] */
+ move.l %a0, _environ /* Store it in the global variable. */
+ pea (%a0) /* Push third argument: envp. */
+ pea 4(%sp) /* Push second argument: argv. */
+ move.l %d0, -(%sp) /* Push first argument: argc. */
+
+ /* Call `_init', which is the entry point to our own `.init'
+ section; and register with `atexit' to have `exit' call
+ `_fini', which is the entry point to our own `.fini' section. */
+ jbsr _init
+ move.l #_fini, -(%sp)
+ jbsr atexit
+ addq.l #4, %sp
+
+ /* Call the user's main function, and exit with its value. */
+ jbsr main
+ move.l %d0, (%sp)
+1: jbsr exit /* This should never return. */
+ jbra 1b /* Try again if somehow it does return. */
+
+/* Define a symbol for the first piece of initialized data. */
+ .data
+ .globl __data_start
+__data_start:
+ .long 0
+ .weak data_start
+ data_start = __data_start
projects / platform / upstream / glibc.git / commitdiff