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-rw-r--r--ports/sysdeps/m68k/dl-machine.h319
1 files changed, 319 insertions, 0 deletions
diff --git a/ports/sysdeps/m68k/dl-machine.h b/ports/sysdeps/m68k/dl-machine.h
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+++ b/ports/sysdeps/m68k/dl-machine.h
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+/* Machine-dependent ELF dynamic relocation inline functions.  m68k version.
+   Copyright (C) 1996-2001, 2002, 2003, 2004, 2005, 2010, 2011
+   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 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/>.  */
+
+#ifndef dl_machine_h
+#define dl_machine_h
+
+#define ELF_MACHINE_NAME "m68k"
+
+#include <sys/param.h>
+#include <sysdep.h>
+#include <dl-tls.h>
+
+/* Return nonzero iff ELF header is compatible with the running host.  */
+static inline int
+elf_machine_matches_host (const Elf32_Ehdr *ehdr)
+{
+  return ehdr->e_machine == EM_68K;
+}
+
+
+/* Return the link-time address of _DYNAMIC.
+   This must be inlined in a function which uses global data.  */
+static inline Elf32_Addr
+elf_machine_dynamic (void)
+{
+  Elf32_Addr addr;
+
+  asm ("move.l _DYNAMIC@GOT.w(%%a5), %0"
+       : "=a" (addr));
+  return addr;
+}
+
+
+/* Return the run-time load address of the shared object.  */
+static inline Elf32_Addr
+elf_machine_load_address (void)
+{
+  Elf32_Addr addr;
+  asm (PCREL_OP ("lea", "_dl_start", "%0", "%0", "%%pc") "\n\t"
+       "sub.l _dl_start@GOT.w(%%a5), %0"
+       : "=a" (addr));
+  return addr;
+}
+
+
+/* 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 __attribute__ ((always_inline))
+elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
+{
+  Elf32_Addr *got;
+  extern void _dl_runtime_resolve (Elf32_Word);
+  extern void _dl_runtime_profile (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 *) D_PTR (l, l_info[DT_PLTGOT]);
+      got[1] = (Elf32_Addr) l;	/* Identify this shared object.  */
+
+      /* The got[2] entry contains the address of a function which gets
+	 called to get the address of a so far unresolved function and
+	 jump to it.  The profiling extension of the dynamic linker allows
+	 to intercept the calls to collect information.  In this case we
+	 don't store the address in the GOT so that all future calls also
+	 end in this function.  */
+      if (profile)
+	{
+	  got[2] = (Elf32_Addr) &_dl_runtime_profile;
+
+	  if (GLRO(dl_profile) != NULL
+	      && _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;
+	    }
+	}
+      else
+	/* 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;
+    }
+
+  return lazy;
+}
+
+#define ELF_MACHINE_RUNTIME_FIXUP_ARGS long int save_a0, long int save_a1
+
+
+/* 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\n\
+	.globl _start\n\
+	.type _start,@function\n\
+_start:\n\
+	sub.l %fp, %fp\n\
+	move.l %sp, -(%sp)\n\
+	jbsr _dl_start\n\
+	addq.l #4, %sp\n\
+	/* FALLTHRU */\n\
+\n\
+	.globl _dl_start_user\n\
+	.type _dl_start_user,@function\n\
+_dl_start_user:\n\
+	| Save the user entry point address in %a4.\n\
+	move.l %d0, %a4\n\
+	| See if we were run as a command with the executable file\n\
+	| name as an extra leading argument.\n\
+	" PCREL_OP ("move.l", "_dl_skip_args", "%d0", "%d0", "%pc") "\n\
+	| Pop the original argument count\n\
+	move.l (%sp)+, %d1\n\
+	| Subtract _dl_skip_args from it.\n\
+	sub.l %d0, %d1\n\
+	| Adjust the stack pointer to skip _dl_skip_args words.\n\
+	lea (%sp, %d0*4), %sp\n\
+	| Push back the modified argument count.\n\
+	move.l %d1, -(%sp)\n\
+	# Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env)\n\
+	pea 8(%sp, %d1*4)\n\
+	pea 8(%sp)\n\
+	move.l %d1, -(%sp)\n\
+	" PCREL_OP ("move.l", "_rtld_local", "-(%sp)", "%d0", "%pc") "\n\
+	jbsr _dl_init_internal@PLTPC\n\
+	addq.l #8, %sp\n\
+	addq.l #8, %sp\n\
+	| Pass our finalizer function to the user in %a1.\n\
+	" PCREL_OP ("lea", "_dl_fini", "%a1", "%a1", "%pc") "\n\
+	| Initialize %fp with the stack pointer.\n\
+	move.l %sp, %fp\n\
+	| Jump to the user's entry point.\n\
+	jmp (%a4)\n\
+	.size _dl_start_user, . - _dl_start_user\n\
+	.previous");
+
+/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry or
+   TLS variable, so undefined references should not be allowed to
+   define the value.
+   ELF_RTYPE_CLASS_NOCOPY iff TYPE should not be allowed to resolve to one
+   of the main executable's symbols, as for a COPY reloc.  */
+#define elf_machine_type_class(type) \
+  ((((type) == R_68K_JMP_SLOT	     \
+     || (type) == R_68K_TLS_DTPMOD32 \
+     || (type) == R_68K_TLS_DTPREL32 \
+     || (type) == R_68K_TLS_TPREL32) * ELF_RTYPE_CLASS_PLT)	\
+   | (((type) == R_68K_COPY) * ELF_RTYPE_CLASS_COPY))
+
+/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries.  */
+#define ELF_MACHINE_JMP_SLOT	R_68K_JMP_SLOT
+
+/* The m68k never uses Elf32_Rel relocations.  */
+#define ELF_MACHINE_NO_REL 1
+
+static inline Elf32_Addr
+elf_machine_fixup_plt (struct link_map *map, lookup_t t,
+		       const Elf32_Rela *reloc,
+		       Elf32_Addr *reloc_addr, Elf32_Addr value)
+{
+  return *reloc_addr = value;
+}
+
+/* Return the final value of a plt relocation.  On the m68k the JMP_SLOT
+   relocation ignores the addend.  */
+static inline Elf32_Addr
+elf_machine_plt_value (struct link_map *map, const Elf32_Rela *reloc,
+		       Elf32_Addr value)
+{
+  return value;
+}
+
+/* Names of the architecture-specific auditing callback functions.  */
+#define ARCH_LA_PLTENTER m68k_gnu_pltenter
+#define ARCH_LA_PLTEXIT m68k_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__ ((unused, always_inline))
+elf_machine_rela (struct link_map *map, const Elf32_Rela *reloc,
+		  const Elf32_Sym *sym, const struct r_found_version *version,
+		  void *const reloc_addr_arg, int skip_ifunc)
+{
+  Elf32_Addr *const reloc_addr = reloc_addr_arg;
+  const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
+
+  if (__builtin_expect (r_type == R_68K_RELATIVE, 0))
+    *reloc_addr = map->l_addr + reloc->r_addend;
+  else
+    {
+      const Elf32_Sym *const refsym = sym;
+      struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
+      Elf32_Addr value = sym == NULL ? 0 : sym_map->l_addr + sym->st_value;
+
+      switch (r_type)
+	{
+	case R_68K_COPY:
+	  if (sym == NULL)
+	    /* This can happen in trace mode if an object could not be
+	       found.  */
+	    break;
+	  if (sym->st_size > refsym->st_size
+	      || (sym->st_size < refsym->st_size && GLRO(dl_verbose)))
+	    {
+	      const char *strtab;
+
+	      strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
+	      _dl_error_printf ("\
+%s: Symbol `%s' has different size in shared object, consider re-linking\n",
+				rtld_progname ?: "<program name unknown>",
+				strtab + refsym->st_name);
+	    }
+	  memcpy (reloc_addr_arg, (void *) value,
+		  MIN (sym->st_size, refsym->st_size));
+	  break;
+	case R_68K_GLOB_DAT:
+	case R_68K_JMP_SLOT:
+	  *reloc_addr = value;
+	  break;
+	case R_68K_8:
+	  *(char *) reloc_addr = value + reloc->r_addend;
+	  break;
+	case R_68K_16:
+	  *(short *) reloc_addr = value + reloc->r_addend;
+	  break;
+	case R_68K_32:
+	  *reloc_addr = value + reloc->r_addend;
+	  break;
+	case R_68K_PC8:
+	  *(char *) reloc_addr
+	    = value + reloc->r_addend - (Elf32_Addr) reloc_addr;
+	  break;
+	case R_68K_PC16:
+	  *(short *) reloc_addr
+	    = value + reloc->r_addend - (Elf32_Addr) reloc_addr;
+	  break;
+	case R_68K_PC32:
+	  *reloc_addr = value + reloc->r_addend - (Elf32_Addr) reloc_addr;
+	  break;
+#ifndef RTLD_BOOTSTRAP
+	case R_68K_TLS_DTPMOD32:
+	  /* Get the information from the link map returned by the
+	     resolv function.  */
+	  if (sym_map != NULL)
+	    *reloc_addr = sym_map->l_tls_modid;
+	  break;
+	case R_68K_TLS_DTPREL32:
+	  if (sym != NULL)
+	    *reloc_addr = TLS_DTPREL_VALUE (sym, reloc);
+	  break;
+	case R_68K_TLS_TPREL32:
+	  if (sym != NULL)
+	    {
+	      CHECK_STATIC_TLS (map, sym_map);
+	      *reloc_addr = TLS_TPREL_VALUE (sym_map, sym, reloc);
+	    }
+	  break;
+#endif /* !RTLD_BOOTSTRAP */
+	case R_68K_NONE:		/* Alright, Wilbur.  */
+	  break;
+	default:
+	  _dl_reloc_bad_type (map, r_type, 0);
+	  break;
+	}
+    }
+}
+
+auto inline void __attribute__ ((unused, always_inline))
+elf_machine_rela_relative (Elf32_Addr l_addr, const Elf32_Rela *reloc,
+			   void *const reloc_addr_arg)
+{
+  Elf32_Addr *const reloc_addr = reloc_addr_arg;
+  *reloc_addr = l_addr + reloc->r_addend;
+}
+
+auto inline void __attribute__ ((unused, always_inline))
+elf_machine_lazy_rel (struct link_map *map,
+		      Elf32_Addr l_addr, const Elf32_Rela *reloc,
+		      int skip_ifunc)
+{
+  Elf32_Addr *const reloc_addr = (void *) (l_addr + reloc->r_offset);
+  if (ELF32_R_TYPE (reloc->r_info) == R_68K_JMP_SLOT)
+    *reloc_addr += l_addr;
+  else
+    _dl_reloc_bad_type (map, ELF32_R_TYPE (reloc->r_info), 1);
+}
+
+#endif /* RESOLVE_MAP */