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-rw-r--r--sysdeps/sparc/sparc32/dl-machine.h363
1 files changed, 363 insertions, 0 deletions
diff --git a/sysdeps/sparc/sparc32/dl-machine.h b/sysdeps/sparc/sparc32/dl-machine.h
new file mode 100644
index 0000000000..f7bcba0c2f
--- /dev/null
+++ b/sysdeps/sparc/sparc32/dl-machine.h
@@ -0,0 +1,363 @@
+/* Machine-dependent ELF dynamic relocation inline functions.  SPARC version.
+   Copyright (C) 1996, 1997 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.,
+   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#define ELF_MACHINE_NAME "sparc"
+
+#include <assert.h>
+#include <string.h>
+#include <link.h>
+#include <sys/param.h>
+
+
+/* Some SPARC opcodes we need to use for self-modifying code.  */
+#define OPCODE_NOP	0x01000000 /* nop */
+#define OPCODE_CALL	0x40000000 /* call ?; add PC-rel word address */
+#define OPCODE_SETHI_G1	0x03000000 /* sethi ?, %g1; add value>>10 */
+#define OPCODE_JMP_G1	0x81c06000 /* jmp %g1+?; add lo 10 bits of value */
+#define OPCODE_SAVE_SP64 0x9de3bfc0 /* save %sp, -64, %sp */
+
+
+/* Return nonzero iff E_MACHINE is compatible with the running host.  */
+static inline int
+elf_machine_matches_host (Elf32_Half e_machine)
+{
+  return e_machine == EM_SPARC;
+}
+
+
+/* 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 Elf32_Addr
+elf_machine_dynamic (void)
+{
+  register Elf32_Addr *got asm ("%l7");
+  return *got;
+}
+
+/* Return the run-time load address of the shared object.  */
+static inline Elf32_Addr
+elf_machine_load_address (void)
+{
+  register Elf32_Addr pc __asm("%o7"), got;
+
+  /* Utilize the fact that a local .got entry will be partially
+     initialized at startup awaiting its RELATIVE fixup.  */
+
+  __asm("sethi %%hi(.Load_address),%1\n"
+        ".Load_address:\n\t"
+        "call 1f\n\t"
+        "or %1,%%lo(.Load_address),%1\n"
+        "1:\tld [%%l7+%1],%1"
+        : "=r"(pc), "=r"(got));
+
+  return pc - got;
+}
+
+  Elf32_Addr addr;
+
+  asm (
+       "add   %%fp,0x44,%%o2\n\t"	/* o2 = point to argc */
+       "ld    [%%o2 - 4],%%o0\n\t"	/* o0 = load argc     */
+       "sll   %%o0, 2, %%o0\n\t"	/* o0 = argc * sizeof (int) */
+       "add   %%o2,%%o0,%%o2\n\t"	/* o2 = skip over argv */
+       "add   %%o2,4,%%o2\n\t"		/* skip over null after argv */
+
+       /* Now %o2 is pointing to env, skip over that as well.  */
+       "1:\n\t"
+       "ld    [%%o2],%%o0\n\t"
+        "cmp   %%o0,0\n\t"
+       "bnz   1b\n\t"
+       "add   %%o2,4,%%o2\n\t"
+
+       /* Note that above, we want to advance the NULL after envp so
+	  we always add 4.  */
+
+       /* Now, search for the AT_BASE property.  */
+       "2:\n\t"
+       "ld   [%%o2],%%o0\n\t"
+       "cmp  %%o0,0\n\t"
+       "be,a 3f\n\t"
+       "or   %%g0,%%g0,%0\n\t"
+       "cmp  %%o0,7\n\t"	/* AT_BASE = 7 */
+       "be,a 3f\n\t"
+       "ld   [%%o2+4],%0\n\t"
+       "b    2b\n\t"
+       "add  %%o2,8,%%o2\n\t"
+       /* At this point %0 has the load address for the interpreter */
+       "3:\n\t"
+       : "=r" (addr)
+       : /* no inputs */
+       : "o0", "o2");
+  return addr;
+}
+
+#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_rela (struct link_map *map, const Elf32_Rela *reloc,
+		  const Elf32_Sym *sym, const struct r_found_version *version,
+		  Elf32_Addr *const reloc_addr)
+{
+  Elf32_Addr loadbase;
+
+  if (ELF32_R_TYPE (reloc->r_info) == R_SPARC_RELATIVE)
+    {
+#ifndef RTLD_BOOTSTRAP
+      if (map != &_dl_rtld_map) /* Already done in rtld itself. */
+#endif
+	*reloc_addr += map->l_addr + reloc->r_addend;
+    }
+  else
+    {
+      const Elf32_Sym *const refsym = sym;
+      Elf32_Addr value;
+      if (sym->st_shndx != SHN_UNDEF &&
+	  ELF32_ST_BIND (sym->st_info) == STB_LOCAL)
+	value = map->l_addr;
+      else
+	{
+	  value = RESOLVE (&sym, version, ELF32_R_TYPE (reloc->r_info));
+	  if (sym)
+	    value += sym->st_value;
+	}
+      value += reloc->r_addend;	/* Assume copy relocs have zero addend.  */
+
+      switch (ELF32_R_TYPE (reloc->r_info))
+	{
+	case R_SPARC_COPY:
+	  if (sym->st_size > refsym->st_size
+	      || (_dl_verbose && sym->st_size < refsym->st_size))
+	    {
+	      extern char **_dl_argv;
+	      const char *strtab;
+
+	      strtab = ((void *) map->l_addr
+			+ map->l_info[DT_STRTAB]->d_un.d_ptr);
+	      _dl_sysdep_error (_dl_argv[0] ?: "<program name unknown>",
+				": Symbol `", strtab + refsym->st_name,
+				"' has different size in shared object, "
+				"consider re-linking\n", NULL);
+	    }
+	  memcpy (reloc_addr, (void *) value, MIN (sym->st_size,
+						   refsym->st_size));
+	  break;
+	case R_SPARC_GLOB_DAT:
+	case R_SPARC_32:
+	  *reloc_addr = value;
+	  break;
+	case R_SPARC_JMP_SLOT:
+	  reloc_addr[1] = OPCODE_SETHI_G1 | (value >> 10);
+	  reloc_addr[2] = OPCODE_JMP_G1 | (value & 0x3ff);
+	  break;
+	case R_SPARC_8:
+	  *(char *) reloc_addr = value;
+	  break;
+	case R_SPARC_16:
+	  *(short *) reloc_addr = value;
+	  break;
+	case R_SPARC_DISP8:
+	  *(char *) reloc_addr = (value - (Elf32_Addr) reloc_addr);
+	  break;
+	case R_SPARC_DISP16:
+	  *(short *) reloc_addr = (value - (Elf32_Addr) reloc_addr);
+	  break;
+	case R_SPARC_DISP32:
+	  *reloc_addr = (value - (Elf32_Addr) reloc_addr);
+	  break;
+	case R_SPARC_LO10:
+	  *reloc_addr = (*reloc_addr & ~0x3ff) | (value & 0x3ff);
+	  break;
+	case R_SPARC_WDISP30:
+	  *reloc_addr = ((*reloc_addr & 0xc0000000)
+			 | ((value - (unsigned int) reloc_addr) >> 2));
+	  break;
+	case R_SPARC_HI22:
+	  *reloc_addr = (*reloc_addr & 0xffc00000) | (value >> 10);
+	  break;
+	case R_SPARC_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)
+{
+  switch (ELF32_R_TYPE (reloc->r_info))
+    {
+    case R_SPARC_NONE:
+      break;
+    case R_SPARC_JMP_SLOT:
+      break;
+    default:
+      assert (! "unexpected PLT reloc type");
+      break;
+    }
+}
+
+#endif	/* RESOLVE */
+
+/* Nonzero iff TYPE should not be allowed to resolve to one of
+   the main executable's symbols, as for a COPY reloc.  */
+#define elf_machine_lookup_noexec_p(type) ((type) == R_SPARC_COPY)
+
+/* Nonzero iff TYPE describes relocation of a PLT entry, so
+   PLT entries should not be allowed to define the value.  */
+#define elf_machine_lookup_noplt_p(type) ((type) == R_SPARC_JMP_SLOT)
+
+/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries.  */
+#define ELF_MACHINE_RELOC_NOPLT	R_SPARC_JMP_SLOT
+
+/* The SPARC never uses Elf32_Rel relocations.  */
+#define ELF_MACHINE_NO_REL 1
+
+/* The SPARC overlaps DT_RELA and DT_PLTREL.  */
+#define ELF_MACHINE_PLTREL_OVERLAP 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 int
+elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
+{
+  Elf32_Addr *plt;
+  extern void _dl_runtime_resolve (Elf32_Word);
+
+  if (l->l_info[DT_JMPREL] && lazy)
+    {
+      /* The entries for functions in the PLT have not yet been filled in.
+	 Their initial contents will arrange when called to set the high 22
+	 bits of %g1 with an offset into the .rela.plt section and jump to
+	 the beginning of the PLT.  */
+      plt = (Elf32_Addr *) (l->l_addr + l->l_info[DT_PLTGOT]->d_un.d_ptr);
+
+      /* The beginning of the PLT does:
+
+	 	save %sp, -64, %sp
+	 pltpc:	call _dl_runtime_resolve
+		nop
+		.word MAP
+
+         This saves the register window containing the arguments, and the
+	 PC value (pltpc) implicitly saved in %o7 by the call points near the
+	 location where we store the link_map pointer for this object.  */
+
+      plt[0] = OPCODE_SAVE_SP64; /* save %sp, -64, %sp */
+      /* Construct PC-relative word address.  */
+      plt[1] = OPCODE_CALL | (((Elf32_Addr) &_dl_runtime_resolve -
+			       (Elf32_Addr) &plt[1]) >> 2);
+      plt[2] = OPCODE_NOP;	/* Fill call delay slot.  */
+      plt[3] = (Elf32_Addr *) l;
+    }
+
+  return lazy;
+}
+
+/* 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:
+	t 1
+	#call  %g0
+	# Pass two args to fixup: the PLT address computed from the PC saved
+	# in the PLT's call insn, and the reloc offset passed in %g1.
+	#ld [%o7 + 8], %o1      | Second arg, loaded from PLTPC[2].
+	#call fixup
+	#shrl %g1, 22, %o0      | First arg, set in delay slot of call.
+	# Jump to the real function.
+	#jmpl %o0, %g0
+	# In the delay slot of that jump, restore the register window
+	# saved by the first insn of the PLT.
+	#restore
+	.size _dl_runtime_resolve, . - _dl_runtime_resolve
+");
+
+/* The PLT uses Elf32_Rela relocs.  */
+#define elf_machine_relplt elf_machine_rela
+
+
+/* Mask identifying addresses reserved for the user program,
+   where the dynamic linker should not map anything.  */
+#define ELF_MACHINE_USER_ADDRESS_MASK	???
+
+/* 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\
+  /* Pass pointer to argument block to _dl_start.  */\n\
+  add %sp,64,%o0\n\
+  call _dl_start\n\
+   nop\n\
+  \n\
+  mov %o0,%l0\n\
+  \n\
+2:\n\
+   call 1f\n\
+   nop\n\
+1:\n\
+  sethi %hi(_GLOBAL_OFFSET_TABLE_-(2b-.)),%l2\n\
+  sethi %hi(_dl_default_scope),%l3\n\
+  or    %l2,%lo(_GLOBAL_OFFSET_TABLE_-(2b-.)),%l2\n\
+  or    %l3,%lo(_dl_default_scope),%l3\n\
+  add   %o7,%l2,%l1\n\
+  # %l1 has the GOT. %l3 has _dl_default_scope GOT offset\n\
+  ld    [%l1+%l3],%l4\n\
+  # %l4 has pointer to _dl_default_scope.  Now, load _dl_default_scope [2]\n\
+  ld    [%l4+8],%l4\n\
+  # %l4 has _dl_default_scope [2]\n\
+  # call _dl_init_next until it returns 0, pass _dl_default_scope [2]\n\
+3:\n\
+  call  _dl_init_next\n\
+   mov   %l4,%o0\n\
+  cmp   %o0,%g0\n\
+  bz,a  4f\n\
+   nop\n\
+  call  %o0\n\
+  /* Pass pointer to argument block to this init function */\n\
+   add %sp,64,%o0\n\
+  b,a   3b\n\
+4:\n\
+  # Clear the _dl_starting_up variable and pass _dl_fini in %g1 as per ELF ABI.\n\
+  sethi %hi(_dl_starting_up),%l4\n\
+  sethi %hi(_dl_fini),%l3\n\
+  or    %l4,%lo(_dl_starting_up),%l4\n\
+  or    %l3,%lo(_dl_fini),%l3\n\
+  # clear _dl_starting_up\n\
+  ld    [%l1+%l4],%l5\n\
+  st    %g0,[%l5]\n\
+  # load out fini function for atexit in %g1\n\
+  ld    [%l3+%l1],%g1\n\
+  # jump to the user program entry point.\n\
+  jmpl %l0,%g0\n\
+  nop\n\
+");