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Re: mips64 n32 and n64 support in dl-machine.h


On Mar 14, 2003, Andreas Jaeger <aj at suse dot de> wrote:

> Getting rid of the mips64-specific file is definitly fine.  I don't
> think it ever worked.

Should I put it in in advance, or wait to check both files in at once?

>> [...]
>> Index: sysdeps/mips/dl-machine.h
>> [...]
>> -/* The MIPS never uses Elfxx_Rela relocations.  */
>> +/* No mips dynamic relocations are RELA.  We do have code in this file
>> +   is conditional to ! ELF_MACHINE_NO_RELA.  It was never

> Shouldn't this be: "We do have code in this file that is..." ?

Yes, thanks.  I'm taking it out, along with the code referenced in the
new comment.

>> +	__builtin_memcpy (&reloc_value, reloc_addr, sizeof (reloc_value));

> Why is this line needed?  I don't understand the need for it.

To support mis-aligned relocations.  According to Ralf Baechle, we
must support them.  I had this in the ChangeLog, but somehow got rid
of it while cleaning up some duplication.

> And why a memcpy and not just an assignment?  Please add a comment to
> explain this line - and the other memcpy line below.

Done.

> I suggest to leave this out completly since it's not used anywhere.

Ok.  I'm adding comments for any differences I had found out between
them.


Here's the revised patch.  Ok?

Index: ChangeLog
2003-03-14  Alexandre Oliva  <aoliva at redhat dot com>

	* 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.

Index: sysdeps/mips/mips64/dl-machine.h
===================================================================
RCS file: sysdeps/mips/mips64/dl-machine.h
diff -N sysdeps/mips/mips64/dl-machine.h
--- sysdeps/mips/mips64/dl-machine.h 28 Feb 2002 22:36:31 -0000 1.21
+++ /dev/null	1 Jan 1970 00:00:00 -0000
@@ -1,594 +0,0 @@
-/* Machine-dependent ELF dynamic relocation inline functions.  MIPS64 version.
-   Copyright (C) 1996,1997,1999,2000,2001,2002 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Kazumoto Kojima <kkojima at info dot kanagawa-u dot ac dot jp>.
-
-   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, write to the Free
-   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
-   02111-1307 USA.  */
-
-#ifndef dl_machine_h
-#define dl_machine_h
-
-#define ELF_MACHINE_NAME "MIPS"
-
-#define ELF_MACHINE_NO_PLT
-
-#include <entry.h>
-
-#ifndef ENTRY_POINT
-#error ENTRY_POINT needs to be defined for MIPS.
-#endif
-
-#ifndef _RTLD_PROLOGUE
-# define _RTLD_PROLOGUE(entry) "\n\t.globl " __STRING(entry)	\
-			       "\n\t.ent " __STRING(entry)	\
-			       "\n\t" __STRING(entry) ":\n\t"
-#endif
-
-#ifndef _RTLD_EPILOGUE
-# define _RTLD_EPILOGUE(entry) "\t.end " __STRING(entry) "\n"
-#endif
-
-/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries.
-   This makes no sense on MIPS but we have to define this to R_MIPS_REL32
-   to avoid the asserts in dl-lookup.c from blowing.  */
-#define ELF_MACHINE_JMP_SLOT			R_MIPS_REL32
-#define elf_machine_type_class(type)		ELF_RTYPE_CLASS_PLT
-
-/* Translate a processor specific dynamic tag to the index
-   in l_info array.  */
-#define DT_MIPS(x) (DT_MIPS_##x - DT_LOPROC + DT_NUM)
-
-#if 0
-/* We may need 64k alignment. */
-#define ELF_MACHINE_ALIGN_MASK 0xffff
-#endif
-
-/*
- * MIPS libraries are usually linked to a non-zero base address.  We
- * subtrace the base address from the address where we map the object
- * to.  This results in more efficient address space usage.
- */
-#if 0
-#define MAP_BASE_ADDR(l) ((l)->l_info[DT_MIPS(BASE_ADDRESS)] ? \
-			  (l)->l_info[DT_MIPS(BASE_ADDRESS)]->d_un.d_ptr : 0)
-#else
-#define MAP_BASE_ADDR(l) 0x5ffe0000
-#endif
-
-/* If there is a DT_MIPS_RLD_MAP entry in the dynamic section, fill it in
-   with the run-time address of the r_debug structure  */
-#define ELF_MACHINE_DEBUG_SETUP(l,r) \
-do { if ((l)->l_info[DT_MIPS (RLD_MAP)]) \
-       *(ElfW(Addr) *)((l)->l_info[DT_MIPS (RLD_MAP)]->d_un.d_ptr) = \
-       (ElfW(Addr)) (r); \
-   } while (0)
-
-/* Return nonzero iff ELF  header is compatible with the running host.  */
-static inline int __attribute__ ((unused))
-elf_machine_matches_host (const ElfW(Ehdr) *ehdr)
-{
-  switch (ehdr->e_machine)
-    {
-    case EM_MIPS:
-    case EM_MIPS_RS3_LE:
-      return 1;
-    default:
-      return 0;
-    }
-}
-
-static inline ElfW(Addr) *
-elf_mips_got_from_gpreg (ElfW(Addr) gpreg)
-{
-  /* FIXME: the offset of gp from GOT may be system-dependent. */
-  return (ElfW(Addr) *) (gpreg - 0x7ff0);
-}
-
-/* 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.  */
-static inline ElfW(Addr)
-elf_machine_dynamic (void)
-{
-  register ElfW(Addr) gp __asm__ ("$28");
-
-  return *elf_mips_got_from_gpreg (gp);
-}
-
-
-/* Return the run-time load address of the shared object.  */
-static inline ElfW(Addr)
-elf_machine_load_address (void)
-{
-  ElfW(Addr) addr;
-  asm ("	.set noreorder\n"
-       "	dla %0, here\n"
-       "	bltzal $0, here\n"
-       "	nop\n"
-       "here:	dsubu %0, $31, %0\n"
-       "	.set reorder\n"
-       :	"=r" (addr)
-       :	/* No inputs */
-       :	"$31");
-  return addr;
-}
-
-/* The MSB of got[1] of a gnu object is set to identify gnu objects. */
-#define ELF_MIPS_GNU_GOT1_MASK 0x80000000
-
-/* Relocate GOT. */
-static inline void
-elf_machine_got_rel (struct link_map *map, int lazy)
-{
-  ElfW(Addr) *got;
-  ElfW(Sym) *sym;
-  int i, n;
-  const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
-
-#define RESOLVE_GOTSYM(sym) \
-    ({ \
-      const ElfW(Sym) *ref = sym; \
-      ElfW(Addr) sym_loadaddr; \
-      sym_loadaddr = _dl_lookup_symbol (strtab + sym->st_name, &ref, \
-					map->l_scope, \
-					map->l_name, R_MIPS_REL32);\
-      (ref)? sym_loadaddr + ref->st_value: 0; \
-    })
-
-  got = (ElfW(Addr) *) D_PTR (map, l_info[DT_PLTGOT]);
-
-  /* got[0] is reserved. got[1] is also reserved for the dynamic object
-     generated by gnu ld. Skip these reserved entries from relocation.  */
-  i = (got[1] & ELF_MIPS_GNU_GOT1_MASK)? 2: 1;
-  n = map->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val;
-  /* Add the run-time display to all local got entries. */
-  while (i < n)
-    got[i++] += map->l_addr;
-
-  /* Handle global got entries. */
-  got += n;
-  sym = (ElfW(Sym) *) D_PTR (map, l_info[DT_SYMTAB]);
-  sym += map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val;
-  i = (map->l_info[DT_MIPS (SYMTABNO)]->d_un.d_val
-       - map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val);
-
-  while (i--)
-    {
-      if (sym->st_shndx == SHN_UNDEF)
-	{
-	  if (ELFW(ST_TYPE) (sym->st_info) == STT_FUNC)
-	    {
-	      if (sym->st_value && lazy)
-		*got = sym->st_value + map->l_addr;
-	      else
-		*got = RESOLVE_GOTSYM (sym);
-	    }
-	  else /* if (*got == 0 || *got == QS) */
-	    *got = RESOLVE_GOTSYM (sym);
-	}
-      else if (sym->st_shndx == SHN_COMMON)
-	*got = RESOLVE_GOTSYM (sym);
-      else if (ELFW(ST_TYPE) (sym->st_info) == STT_FUNC
-	       && *got != sym->st_value
-	       && lazy)
-	*got += map->l_addr;
-      else if (ELFW(ST_TYPE) (sym->st_info) == STT_SECTION)
-	{
-	  if (sym->st_other == 0)
-	    *got += map->l_addr;
-	}
-      else
-	*got = RESOLVE_GOTSYM (sym);
-
-      got++;
-      sym++;
-    }
-
-#undef RESOLVE_GOTSYM
-
-  return;
-}
-
-/* Set up the loaded object described by L so its stub function
-   will jump to the on-demand fixup code in dl-runtime.c.  */
-
-static inline int
-elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
-{
-  ElfW(Addr) *got;
-  extern void _dl_runtime_resolve (ElfW(Word));
-  extern int _dl_mips_gnu_objects;
-
-#ifdef RTLD_BOOTSTRAP
-    {
-      return lazy;
-    }
-#endif
-  if (lazy)
-    {
-      /* The GOT entries for functions have not yet been filled in.
-	 Their initial contents will arrange when called to put an
-	 offset into the .dynsym section in t8, the return address
-	 in t7 and then jump to _GLOBAL_OFFSET_TABLE[0].  */
-      got = (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]);
-
-      /* This function will get called to fix up the GOT entry indicated by
-	 the register t8, and then jump to the resolved address.  */
-      got[0] = (ElfW(Addr)) &_dl_runtime_resolve;
-
-      /* Store l to _GLOBAL_OFFSET_TABLE[1] for gnu object. The MSB
-	 of got[1] of a gnu object is set to identify gnu objects.
-	 Where we can store l for non gnu objects? XXX  */
-      if ((got[1] & ELF_MIPS_GNU_GOT1_MASK) != 0)
-	got[1] = (ElfW(Addr)) ((unsigned) l | ELF_MIPS_GNU_GOT1_MASK);
-      else
-	_dl_mips_gnu_objects = 0;
-    }
-
-  /* Relocate global offset table.  */
-  elf_machine_got_rel (l, lazy);
-
-  return lazy;
-}
-
-/* Get link_map for this object.  */
-static inline struct link_map *
-elf_machine_runtime_link_map (ElfW(Addr) gpreg, ElfW(Addr) stub_pc)
-{
-  extern int _dl_mips_gnu_objects;
-
-  /* got[1] is reserved to keep its link map address for the shared
-     object generated by the gnu linker.  If all are such objects, we
-     can find the link map from current GPREG simply.  If not so, get
-     the link map for caller's object containing STUB_PC.  */
-
-  if (_dl_mips_gnu_objects)
-    {
-      ElfW(Addr) *got = elf_mips_got_from_gpreg (gpreg);
-      ElfW(Word) g1;
-
-      g1 = ((ElfW(Word) *) got)[1];
-
-      if ((g1 & ELF_MIPS_GNU_GOT1_MASK) != 0)
-	{
-	  struct link_map *l =
-	    (struct link_map *) (g1 & ~ELF_MIPS_GNU_GOT1_MASK);
-	  ElfW(Addr) base, limit;
-	  const ElfW(Phdr) *p = l->l_phdr;
-	  ElfW(Half) this, nent = l->l_phnum;
-
-	  /* For the common case of a stub being called from the containing
-	     object, STUB_PC will point to somewhere within the object that
-	     is described by the link map fetched via got[1].  Otherwise we
-	     have to scan all maps.  */
-	  for (this = 0; this < nent; this++)
-	    {
-	      if (p[this].p_type == PT_LOAD)
-		{
-		  base = p[this].p_vaddr + l->l_addr;
-		  limit = base + p[this].p_memsz;
-		  if (stub_pc >= base && stub_pc < limit)
-		    return l;
-		}
-	      this++;
-	    }
-	}
-    }
-
-    {
-      struct link_map *l = GL(dl_loaded);
-
-      while (l)
-	{
-	  ElfW(Addr) base, limit;
-	  const ElfW(Phdr) *p = l->l_phdr;
-	  ElfW(Half) this, nent = l->l_phnum;
-
-	  for (this = 0; this < nent; this++)
-	    {
-	      if (p[this].p_type == PT_LOAD)
-		{
-		  base = p[this].p_vaddr + l->l_addr;
-		  limit = base + p[this].p_memsz;
-		  if (stub_pc >= base && stub_pc < limit)
-		    return l;
-		}
-	    }
-	  l = l->l_next;
-	}
-    }
-
-  _dl_signal_error (0, NULL, NULL, "cannot find runtime link map");
-  return NULL;
-}
-
-/* Mips has no PLT but define elf_machine_relplt to be elf_machine_rel. */
-#define elf_machine_relplt elf_machine_rel
-
-/* 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):
-     t7  address to return to the caller of the function
-     t8  index for this function symbol in .dynsym
-   to usual c arguments.  */
-
-#define ELF_MACHINE_RUNTIME_TRAMPOLINE					      \
-/* The flag _dl_mips_gnu_objects is set if all dynamic objects are	      \
-   generated by the gnu linker. */					      \
-int _dl_mips_gnu_objects = 1;						      \
-									      \
-/* This is called from assembly stubs below which the compiler can't see.  */ \
-static ElfW(Addr)							      \
-__dl_runtime_resolve (ElfW(Word), ElfW(Word), ElfW(Addr), ElfW(Addr))	      \
-                  __attribute__ ((unused));				      \
-									      \
-static ElfW(Addr)							      \
-__dl_runtime_resolve (ElfW(Word) sym_index,				      \
-		      ElfW(Word) return_address,			      \
-		      ElfW(Addr) old_gpreg,				      \
-		      ElfW(Addr) stub_pc)				      \
-{									      \
-  struct link_map *l = elf_machine_runtime_link_map (old_gpreg, stub_pc);     \
-  const ElfW(Sym) *const symtab						      \
-    = (const ElfW(Sym) *) D_PTR (l, l_info[DT_SYMTAB]);			      \
-  const char *strtab = (const void *) D_PTR (l, l_info[DT_STRTAB]);	      \
-  const ElfW(Addr) *got							      \
-    = (const ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]);		      \
-  const ElfW(Word) local_gotno						      \
-    = (const ElfW(Word)) l->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val;	      \
-  const ElfW(Word) gotsym						      \
-    = (const ElfW(Word)) l->l_info[DT_MIPS (GOTSYM)]->d_un.d_val;	      \
-  const ElfW(Sym) *definer;						      \
-  ElfW(Addr) loadbase;							      \
-  ElfW(Addr) funcaddr;							      \
-									      \
-  /* Look up the symbol's run-time value.  */				      \
-  definer = &symtab[sym_index];						      \
-									      \
-  loadbase = _dl_lookup_symbol (strtab + definer->st_name, &definer,	      \
-				l->l_scope, l->l_name,			      \
-				R_MIPS_REL32);				      \
-									      \
-  /* Apply the relocation with that value.  */				      \
-  funcaddr = loadbase + definer->st_value;				      \
-  *(got + local_gotno + sym_index - gotsym) = funcaddr;			      \
-									      \
-  return funcaddr;							      \
-}									      \
-									      \
-asm ("\n								      \
-	.text\n								      \
-	.align	3\n							      \
-	.globl	_dl_runtime_resolve\n					      \
-	.type	_dl_runtime_resolve,@function\n				      \
-	.ent	_dl_runtime_resolve\n					      \
-_dl_runtime_resolve:\n							      \
-	.set noreorder\n						      \
-	# Save old GP to $3.\n						      \
-	move	$3,$28\n						      \
-	# Modify t9 ($25) so as to point .cpload instruction.\n		      \
-	daddu	$25,2*8\n						      \
-	# Compute GP.\n							      \
-	.cpload $25\n							      \
-	.set reorder\n							      \
-	# Save slot call pc.\n						      \
-        move	$2, $31\n						      \
-	# Save arguments and sp value in stack.\n			      \
-	dsubu	$29, 10*8\n						      \
-	.cprestore 8*8\n						      \
-	sd	$15, 9*8($29)\n						      \
-	sd	$4, 3*8($29)\n						      \
-	sd	$5, 4*8($29)\n						      \
-	sd	$6, 5*8($29)\n						      \
-	sd	$7, 6*8($29)\n						      \
-	sd	$16, 7*8($29)\n						      \
-	move	$16, $29\n						      \
-	move	$4, $24\n						      \
-	move	$5, $15\n						      \
-	move	$6, $3\n						      \
-	move	$7, $2\n						      \
-	jal	__dl_runtime_resolve\n					      \
-	move	$29, $16\n						      \
-	ld	$31, 9*8($29)\n						      \
-	ld	$4, 3*8($29)\n						      \
-	ld	$5, 4*8($29)\n						      \
-	ld	$6, 5*8($29)\n						      \
-	ld	$7, 6*8($29)\n						      \
-	ld	$16, 7*8($29)\n						      \
-	daddu	$29, 10*8\n						      \
-	move	$25, $2\n						      \
-	jr	$25\n							      \
-	.end	_dl_runtime_resolve\n					      \
-	.previous\n							      \
-");
-
-/* 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.
-   Note how we have to be careful about two things:
-
-   1) That we allocate a minimal stack of 24 bytes for
-      every function call, the MIPS ABI states that even
-      if all arguments are passed in registers the procedure
-      called can use the 16 byte area pointed to by $sp
-      when it is called to store away the arguments passed
-      to it.
-
-   2) That under Linux the entry is named __start
-      and not just plain _start.  */
-
-#define RTLD_START asm ("\
-	.text\n\
-	.align	3\n"\
-_RTLD_PROLOGUE (ENTRY_POINT)\
-"	.globl _dl_start_user\n\
-	.set noreorder\n\
-	bltzal $0, 0f\n\
-	nop\n\
-0:	.cpload $31\n\
-	.set reorder\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\
-	dla $4, _DYNAMIC\n\
-	sd $4, -0x7ff0($28)\n\
-	dsubu $29, 16\n\
-	move $4, $29\n\
-	jal _dl_start\n\
-	daddiu $29, 16\n\
-	# Get the value of label '_dl_start_user' in t9 ($25).\n\
-	dla $25, _dl_start_user\n\
-_dl_start_user:\n\
-	.set noreorder\n\
-	.cpload $25\n\
-	.set reorder\n\
-	move $16, $28\n\
-	# Save the user entry point address in saved register.\n\
-	move $17, $2\n\
-	# Store the highest stack address\n\
-	sd $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\
-	ld $2, _dl_skip_args\n\
-	beq $2, $0, 1f\n\
-	# Load the original argument count.\n\
-	ld $4, 0($29)\n\
-	# Subtract _dl_skip_args from it.\n\
-	dsubu $4, $2\n\
-	# Adjust the stack pointer to skip _dl_skip_args words.\n\
-	dsll $2,2\n\
-	daddu $29, $2\n\
-	# Save back the modified argument count.\n\
-	sd $4, 0($29)\n\
-1:	# Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env) \n\
-	ld $4, _rtld_local\n\
-	ld $5, 0($29)\n\
-	dla $6, 4($29)\n\
-	dla $7, 8($29)\n\
-	dsubu $29, 16\n\
-	# Call the function to run the initializers.\n\
-	jal _dl_init_internal\n\
-	daddiu $29, 16\n\
-	# Pass our finalizer function to the user in ra.\n\
-	dla $31, _dl_fini\n\
-	# Jump to the user entry point.\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\
-	la $7, 8($29)\n\
-	subu $29, 16\n\
-	# Call the function to run the initializers.\n\
-	jal _dl_init_internal\n\
-	addiu $29, 16\n\
-	# Pass our finalizer function to the user in ra.\n\
-	dla $31, _dl_fini\n\
-	# Jump to the user entry point.\n\
-	move $25, $17\n\
-	ld $4, 0($29)\n\
-	ld $5, 1*8($29)\n\
-	ld $6, 2*8$29)\n\
-	ld $7, 3*8($29)\n\
-	jr $25\n"\
-_RTLD_EPILOGUE(ENTRY_POINT) \
-	"\n.previous"\
-);
-
-
-/* The MIPS never uses Elfxx_Rela relocations.  */
-#define ELF_MACHINE_NO_RELA 1
-
-#endif /* !dl_machine_h */
-
-#ifdef RESOLVE
-
-/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
-   MAP is the object containing the reloc.  */
-
-static inline void
-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)
-{
-  const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info);
-  ElfW(Addr) loadbase;
-  ElfW(Addr) undo __attribute__ ((unused));
-
-  switch (r_type)
-    {
-    case R_MIPS_REL32:
-      {
-	ElfW(Addr) undo = 0;
-
-	if (ELFW(ST_BIND) (sym->st_info) == STB_LOCAL
-	    && (ELFW(ST_TYPE) (sym->st_info) == STT_SECTION
-		|| ELFW(ST_TYPE) (sym->st_info) == STT_NOTYPE))
-	  {
-	    *reloc_addr += map->l_addr;
-	    break;
-	  }
-#ifndef RTLD_BOOTSTRAP
-	/* 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.  */
-# ifndef SHARED
-	weak_extern (GL(dl_rtld_map));
-# endif
-	if (map == &GL(dl_rtld_map))
-	  /* Undo the relocation done here during bootstrapping.  Now we will
-	     relocate it anew, possibly using a binding found in the user
-	     program or a loaded library rather than the dynamic linker's
-	     built-in definitions used while loading those libraries.  */
-	  undo = map->l_addr + sym->st_value;
-#endif
-	  loadbase = RESOLVE (&sym, version, 0);
-	  *reloc_addr += (sym ? (loadbase + sym->st_value) : 0) - undo;
-	}
-      break;
-#ifndef RTLD_BOOTSTRAP
-    case R_MIPS_NONE:		/* Alright, Wilbur.  */
-      break;
-#endif
-    default:
-      _dl_reloc_bad_type (map, r_type, 0);
-      break;
-    }
-}
-
-static inline void
-elf_machine_rel_relative (ElfW(Addr) l_addr, const ElfW(Rel) *reloc,
-			  ElfW(Addr) *const reloc_addr)
-{
-  /* XXX Nothing to do.  There is no relative relocation, right?  */
-}
-
-static inline void
-elf_machine_lazy_rel (struct link_map *map, ElfW(Addr) l_addr,
-		      const ElfW(Rel) *reloc)
-{
-  /* Do nothing.  */
-}
-
-#endif /* RESOLVE */
Index: sysdeps/mips/dl-machine.h
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/mips/dl-machine.h,v
retrieving revision 1.65
diff -u -p -r1.65 dl-machine.h
--- sysdeps/mips/dl-machine.h 12 Feb 2003 09:42:48 -0000 1.65
+++ sysdeps/mips/dl-machine.h 14 Mar 2003 07:43:38 -0000
@@ -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) gpre
 
 /* 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)
   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_ind
 {									      \
   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, c
 
   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, c
 
 	    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, c
 		  = (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, c
 #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;
-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                 aoliva at {redhat dot com, gcc.gnu.org}
CS PhD student at IC-Unicamp        oliva at {lsd dot ic dot unicamp dot br, gnu.org}
Free Software Evangelist                Professional serial bug killer

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