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-rw-r--r--REORG.TODO/sysdeps/powerpc/powerpc32/dl-machine.h455
1 files changed, 455 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/powerpc/powerpc32/dl-machine.h b/REORG.TODO/sysdeps/powerpc/powerpc32/dl-machine.h
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index 0000000000..28eb50f92d
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+++ b/REORG.TODO/sysdeps/powerpc/powerpc32/dl-machine.h
@@ -0,0 +1,455 @@
+/* Machine-dependent ELF dynamic relocation inline functions.  PowerPC version.
+   Copyright (C) 1995-2017 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 "powerpc"
+
+#include <assert.h>
+#include <dl-tls.h>
+#include <dl-irel.h>
+#include <hwcapinfo.h>
+
+/* Translate a processor specific dynamic tag to the index
+   in l_info array.  */
+#define DT_PPC(x) (DT_PPC_##x - DT_LOPROC + DT_NUM)
+
+/* 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_PPC;
+}
+
+/* Return the value of the GOT pointer.  */
+static inline Elf32_Addr * __attribute__ ((const))
+ppc_got (void)
+{
+  Elf32_Addr *got;
+
+  asm ("bcl 20,31,1f\n"
+       "1:	mflr %0\n"
+       "	addis %0,%0,_GLOBAL_OFFSET_TABLE_-1b@ha\n"
+       "	addi %0,%0,_GLOBAL_OFFSET_TABLE_-1b@l\n"
+       : "=b" (got) : : "lr");
+
+  return got;
+}
+
+/* Return the link-time address of _DYNAMIC, stored as
+   the first value in the GOT. */
+static inline Elf32_Addr __attribute__ ((const))
+elf_machine_dynamic (void)
+{
+  return *ppc_got ();
+}
+
+/* Return the run-time load address of the shared object.  */
+static inline Elf32_Addr __attribute__ ((const))
+elf_machine_load_address (void)
+{
+  Elf32_Addr *branchaddr;
+  Elf32_Addr runtime_dynamic;
+
+  /* This is much harder than you'd expect.  Possibly I'm missing something.
+     The 'obvious' way:
+
+       Apparently, "bcl 20,31,$+4" is what should be used to load LR
+       with the address of the next instruction.
+       I think this is so that machines that do bl/blr pairing don't
+       get confused.
+
+     asm ("bcl 20,31,0f ;"
+	  "0: mflr 0 ;"
+	  "lis %0,0b@ha;"
+	  "addi %0,%0,0b@l;"
+	  "subf %0,%0,0"
+	  : "=b" (addr) : : "r0", "lr");
+
+     doesn't work, because the linker doesn't have to (and in fact doesn't)
+     update the @ha and @l references; the loader (which runs after this
+     code) will do that.
+
+     Instead, we use the following trick:
+
+     The linker puts the _link-time_ address of _DYNAMIC at the first
+     word in the GOT. We could branch to that address, if we wanted,
+     by using an @local reloc; the linker works this out, so it's safe
+     to use now. We can't, of course, actually branch there, because
+     we'd cause an illegal instruction exception; so we need to compute
+     the address ourselves. That gives us the following code: */
+
+  /* Get address of the 'b _DYNAMIC@local'...  */
+  asm ("bcl 20,31,0f;"
+       "b _DYNAMIC@local;"
+       "0:"
+       : "=l" (branchaddr));
+
+  /* So now work out the difference between where the branch actually points,
+     and the offset of that location in memory from the start of the file.  */
+  runtime_dynamic = ((Elf32_Addr) branchaddr
+		     + ((Elf32_Sword) (*branchaddr << 6 & 0xffffff00) >> 6));
+
+  return runtime_dynamic - elf_machine_dynamic ();
+}
+
+#define ELF_MACHINE_BEFORE_RTLD_RELOC(dynamic_info) /* nothing */
+
+/* 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	0xf0000000UL
+
+/* The actual _start code is in dl-start.S.  Use a really
+   ugly bit of assembler to let dl-start.o see _dl_start.  */
+#define RTLD_START asm (".globl _dl_start");
+
+/* Decide where a relocatable object should be loaded.  */
+extern ElfW(Addr)
+__elf_preferred_address(struct link_map *loader, size_t maplength,
+			ElfW(Addr) mapstartpref);
+#define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) \
+  __elf_preferred_address (loader, maplength, mapstartpref)
+
+/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry, so
+   PLT entries 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.  */
+/* We never want to use a PLT entry as the destination of a
+   reloc, when what is being relocated is a branch. This is
+   partly for efficiency, but mostly so we avoid loops.  */
+#define elf_machine_type_class(type)			\
+  ((((type) == R_PPC_JMP_SLOT				\
+    || (type) == R_PPC_REL24				\
+    || ((type) >= R_PPC_DTPMOD32 /* contiguous TLS */	\
+	&& (type) <= R_PPC_DTPREL32)			\
+    || (type) == R_PPC_ADDR24) * ELF_RTYPE_CLASS_PLT)	\
+   | (((type) == R_PPC_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_PPC_JMP_SLOT
+
+/* The PowerPC never uses REL relocations.  */
+#define ELF_MACHINE_NO_REL 1
+#define ELF_MACHINE_NO_RELA 0
+
+/* We define an initialization function to initialize HWCAP/HWCAP2 and
+   platform data so it can be copied into the TCB later.  This is called
+   very early in _dl_sysdep_start for dynamically linked binaries.  */
+#ifdef SHARED
+# define DL_PLATFORM_INIT dl_platform_init ()
+
+static inline void __attribute__ ((unused))
+dl_platform_init (void)
+{
+  __tcb_parse_hwcap_and_convert_at_platform ();
+}
+#endif
+
+/* Set up the loaded object described by MAP so its unrelocated PLT
+   entries will jump to the on-demand fixup code in dl-runtime.c.
+   Also install a small trampoline to be used by entries that have
+   been relocated to an address too far away for a single branch.  */
+extern int __elf_machine_runtime_setup (struct link_map *map,
+					int lazy, int profile);
+
+static inline int
+elf_machine_runtime_setup (struct link_map *map,
+			   int lazy, int profile)
+{
+  if (map->l_info[DT_JMPREL] == 0)
+    return lazy;
+
+  if (map->l_info[DT_PPC(GOT)] == 0)
+    /* Handle old style PLT.  */
+    return __elf_machine_runtime_setup (map, lazy, profile);
+
+  /* New style non-exec PLT consisting of an array of addresses.  */
+  map->l_info[DT_PPC(GOT)]->d_un.d_ptr += map->l_addr;
+  if (lazy)
+    {
+      Elf32_Addr *plt, *got, glink;
+      Elf32_Word num_plt_entries;
+      void (*dlrr) (void);
+      extern void _dl_runtime_resolve (void);
+      extern void _dl_prof_resolve (void);
+
+      if (__glibc_likely (!profile))
+	dlrr = _dl_runtime_resolve;
+      else
+	{
+	  if (GLRO(dl_profile) != NULL
+	      &&_dl_name_match_p (GLRO(dl_profile), map))
+	    GL(dl_profile_map) = map;
+	  dlrr = _dl_prof_resolve;
+	}
+      got = (Elf32_Addr *) map->l_info[DT_PPC(GOT)]->d_un.d_ptr;
+      glink = got[1];
+      got[1] = (Elf32_Addr) dlrr;
+      got[2] = (Elf32_Addr) map;
+
+      /* Relocate everything in .plt by the load address offset.  */
+      plt = (Elf32_Addr *) D_PTR (map, l_info[DT_PLTGOT]);
+      num_plt_entries = (map->l_info[DT_PLTRELSZ]->d_un.d_val
+			 / sizeof (Elf32_Rela));
+
+      /* If a library is prelinked but we have to relocate anyway,
+	 we have to be able to undo the prelinking of .plt section.
+	 The prelinker saved us at got[1] address of .glink
+	 section's start.  */
+      if (glink)
+	{
+	  glink += map->l_addr;
+	  while (num_plt_entries-- != 0)
+	    *plt++ = glink, glink += 4;
+	}
+      else
+	while (num_plt_entries-- != 0)
+	  *plt++ += map->l_addr;
+    }
+  return lazy;
+}
+
+/* Change the PLT entry whose reloc is 'reloc' to call the actual routine.  */
+extern Elf32_Addr __elf_machine_fixup_plt (struct link_map *map,
+					   Elf32_Addr *reloc_addr,
+					   Elf32_Addr finaladdr);
+
+static inline Elf32_Addr
+elf_machine_fixup_plt (struct link_map *map, lookup_t t,
+		       const Elf32_Rela *reloc,
+		       Elf32_Addr *reloc_addr, Elf64_Addr finaladdr)
+{
+  if (map->l_info[DT_PPC(GOT)] == 0)
+    /* Handle old style PLT.  */
+    return __elf_machine_fixup_plt (map, reloc_addr, finaladdr);
+
+  *reloc_addr = finaladdr;
+  return finaladdr;
+}
+
+/* Return the final value of a plt relocation.  */
+static inline Elf32_Addr
+elf_machine_plt_value (struct link_map *map, const Elf32_Rela *reloc,
+		       Elf32_Addr value)
+{
+  return value + reloc->r_addend;
+}
+
+
+/* Names of the architecture-specific auditing callback functions.  */
+#define ARCH_LA_PLTENTER ppc32_gnu_pltenter
+#define ARCH_LA_PLTEXIT ppc32_gnu_pltexit
+
+#endif /* dl_machine_h */
+
+#ifdef RESOLVE_MAP
+
+/* Do the actual processing of a reloc, once its target address
+   has been determined.  */
+extern void __process_machine_rela (struct link_map *map,
+				    const Elf32_Rela *reloc,
+				    struct link_map *sym_map,
+				    const Elf32_Sym *sym,
+				    const Elf32_Sym *refsym,
+				    Elf32_Addr *const reloc_addr,
+				    Elf32_Addr finaladdr,
+				    int rinfo) attribute_hidden;
+
+/* Call _dl_signal_error when a resolved value overflows a relocated area.  */
+extern void _dl_reloc_overflow (struct link_map *map,
+				const char *name,
+				Elf32_Addr *const reloc_addr,
+				const Elf32_Sym *refsym) attribute_hidden;
+
+/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
+   LOADADDR is the load address of the object; INFO is an array indexed
+   by DT_* of the .dynamic section info.  */
+
+auto inline void __attribute__ ((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 Elf32_Sym *const refsym = sym;
+  Elf32_Addr value;
+  const int r_type = ELF32_R_TYPE (reloc->r_info);
+  struct link_map *sym_map = NULL;
+
+#ifndef RESOLVE_CONFLICT_FIND_MAP
+  if (r_type == R_PPC_RELATIVE)
+    {
+      *reloc_addr = map->l_addr + reloc->r_addend;
+      return;
+    }
+
+  if (__glibc_unlikely (r_type == R_PPC_NONE))
+    return;
+
+  /* binutils on ppc32 includes st_value in r_addend for relocations
+     against local symbols.  */
+  if (__builtin_expect (ELF32_ST_BIND (sym->st_info) == STB_LOCAL, 0)
+      && sym->st_shndx != SHN_UNDEF)
+    value = map->l_addr;
+  else
+    {
+      sym_map = RESOLVE_MAP (&sym, version, r_type);
+      value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value;
+    }
+  value += reloc->r_addend;
+#else
+  value = reloc->r_addend;
+#endif
+
+  if (sym != NULL
+      && __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC, 0)
+      && __builtin_expect (sym->st_shndx != SHN_UNDEF, 1)
+      && __builtin_expect (!skip_ifunc, 1))
+    value = elf_ifunc_invoke (value);
+
+  /* A small amount of code is duplicated here for speed.  In libc,
+     more than 90% of the relocs are R_PPC_RELATIVE; in the X11 shared
+     libraries, 60% are R_PPC_RELATIVE, 24% are R_PPC_GLOB_DAT or
+     R_PPC_ADDR32, and 16% are R_PPC_JMP_SLOT (which this routine
+     wouldn't usually handle).  As an bonus, doing this here allows
+     the switch statement in __process_machine_rela to work.  */
+  switch (r_type)
+    {
+    case R_PPC_GLOB_DAT:
+    case R_PPC_ADDR32:
+      *reloc_addr = value;
+      break;
+
+#ifndef RESOLVE_CONFLICT_FIND_MAP
+# ifdef RTLD_BOOTSTRAP
+#  define NOT_BOOTSTRAP 0
+# else
+#  define NOT_BOOTSTRAP 1
+# endif
+
+    case R_PPC_DTPMOD32:
+      if (map->l_info[DT_PPC(OPT)]
+	  && (map->l_info[DT_PPC(OPT)]->d_un.d_val & PPC_OPT_TLS))
+	{
+	  if (!NOT_BOOTSTRAP)
+	    {
+	      reloc_addr[0] = 0;
+	      reloc_addr[1] = (sym_map->l_tls_offset - TLS_TP_OFFSET
+			       + TLS_DTV_OFFSET);
+	      break;
+	    }
+	  else if (sym_map != NULL)
+	    {
+# ifndef SHARED
+	      CHECK_STATIC_TLS (map, sym_map);
+# else
+	      if (TRY_STATIC_TLS (map, sym_map))
+# endif
+		{
+		  reloc_addr[0] = 0;
+		  /* Set up for local dynamic.  */
+		  reloc_addr[1] = (sym_map->l_tls_offset - TLS_TP_OFFSET
+				   + TLS_DTV_OFFSET);
+		  break;
+		}
+	    }
+	}
+      if (!NOT_BOOTSTRAP)
+	/* During startup the dynamic linker is always index 1.  */
+	*reloc_addr = 1;
+      else if (sym_map != NULL)
+	/* Get the information from the link map returned by the
+	   RESOLVE_MAP function.  */
+	*reloc_addr = sym_map->l_tls_modid;
+      break;
+    case R_PPC_DTPREL32:
+      if (map->l_info[DT_PPC(OPT)]
+	  && (map->l_info[DT_PPC(OPT)]->d_un.d_val & PPC_OPT_TLS))
+	{
+	  if (!NOT_BOOTSTRAP)
+	    {
+	      *reloc_addr = TLS_TPREL_VALUE (sym_map, sym, reloc);
+	      break;
+	    }
+	  else if (sym_map != NULL)
+	    {
+	      /* This reloc is always preceded by R_PPC_DTPMOD32.  */
+# ifndef SHARED
+	      assert (HAVE_STATIC_TLS (map, sym_map));
+# else
+	      if (HAVE_STATIC_TLS (map, sym_map))
+# endif
+		{
+		  *reloc_addr = TLS_TPREL_VALUE (sym_map, sym, reloc);
+		  break;
+		}
+	    }
+	}
+      /* During relocation all TLS symbols are defined and used.
+	 Therefore the offset is already correct.  */
+      if (NOT_BOOTSTRAP && sym_map != NULL)
+	*reloc_addr = TLS_DTPREL_VALUE (sym, reloc);
+      break;
+    case R_PPC_TPREL32:
+      if (!NOT_BOOTSTRAP || sym_map != NULL)
+	{
+	  if (NOT_BOOTSTRAP)
+	    CHECK_STATIC_TLS (map, sym_map);
+	  *reloc_addr = TLS_TPREL_VALUE (sym_map, sym, reloc);
+	}
+      break;
+#endif
+
+    case R_PPC_JMP_SLOT:
+#ifdef RESOLVE_CONFLICT_FIND_MAP
+      RESOLVE_CONFLICT_FIND_MAP (map, reloc_addr);
+#endif
+      if (map->l_info[DT_PPC(GOT)] != 0)
+	{
+	  *reloc_addr = value;
+	  break;
+	}
+      /* FALLTHROUGH */
+
+    default:
+      __process_machine_rela (map, reloc, sym_map, sym, refsym,
+			      reloc_addr, value, r_type);
+    }
+}
+
+auto inline void __attribute__ ((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__ ((always_inline))
+elf_machine_lazy_rel (struct link_map *map,
+		      Elf32_Addr l_addr, const Elf32_Rela *reloc,
+		      int skip_ifunc)
+{
+  /* elf_machine_runtime_setup handles this. */
+}
+
+#endif /* RESOLVE_MAP */