1 files changed, 401 insertions, 0 deletions

diff --git a/sysdeps/aarch64/dl-machine.h b/sysdeps/aarch64/dl-machine.h
new file mode 100644
index 0000000..997c860
--- /dev/null
+++ b/sysdeps/aarch64/dl-machine.h
@@ -0,0 +1,401 @@
+/* Copyright (C) 1995-2014 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 "aarch64"
+
+#include <tls.h>
+#include <dl-tlsdesc.h>
+#include <dl-irel.h>
+
+/* Return nonzero iff ELF header is compatible with the running host.  */
+static inline int __attribute__ ((unused))
+elf_machine_matches_host (const ElfW(Ehdr) *ehdr)
+{
+  return ehdr->e_machine == EM_AARCH64;
+}
+
+/* Return the link-time address of _DYNAMIC.  Conveniently, this is the
+   first element of the GOT. */
+static inline ElfW(Addr) __attribute__ ((unused))
+elf_machine_dynamic (void)
+{
+  extern const ElfW(Addr) _GLOBAL_OFFSET_TABLE_[] attribute_hidden;
+  return _GLOBAL_OFFSET_TABLE_[0];
+}
+
+/* Return the run-time load address of the shared object.  */
+
+static inline ElfW(Addr) __attribute__ ((unused))
+elf_machine_load_address (void)
+{
+  /* To figure out the load address we use the definition that for any symbol:
+     dynamic_addr(symbol) = static_addr(symbol) + load_addr
+
+     The choice of symbol is arbitrary. The static address we obtain
+     by constructing a non GOT reference to the symbol, the dynamic
+     address of the symbol we compute using adrp/add to compute the
+     symbol's address relative to the PC. */
+
+  ElfW(Addr) static_addr;
+  ElfW(Addr) dynamic_addr;
+
+  asm ("					\n\
+	adrp	%1, _dl_start;			\n\
+        add	%1, %1, #:lo12:_dl_start        \n\
+        ldr	%w0, 1f				\n\
+	b	2f				\n\
+1:	.word	_dl_start			\n\
+2:						\n\
+       " : "=r" (static_addr),  "=r" (dynamic_addr));
+  return dynamic_addr - static_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__ ((unused))
+elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
+{
+  if (l->l_info[DT_JMPREL] && lazy)
+    {
+      ElfW(Addr) *got;
+      extern void _dl_runtime_resolve (ElfW(Word));
+      extern void _dl_runtime_profile (ElfW(Word));
+
+      got = (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]);
+      if (got[1])
+	{
+	  l->l_mach.plt = got[1] + l->l_addr;
+	}
+      got[1] = (ElfW(Addr)) l;
+
+      /* 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] = (ElfW(Addr)) &_dl_runtime_profile;
+
+	  if (GLRO(dl_profile) != NULL
+	      && _dl_name_match_p (GLRO(dl_profile), l))
+	    /* 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] = (ElfW(Addr)) &_dl_runtime_resolve;
+	}
+    }
+
+  if (l->l_info[ADDRIDX (DT_TLSDESC_GOT)] && lazy)
+    *(Elf64_Addr*)(D_PTR (l, l_info[ADDRIDX (DT_TLSDESC_GOT)]) + l->l_addr)
+      = (Elf64_Addr) &_dl_tlsdesc_resolve_rela;
+
+  return lazy;
+}
+
+/* Initial entry point 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\
+.globl _dl_start_user						\n\
+.type _dl_start_user, %function					\n\
+_start:								\n\
+	mov	x0,	sp					\n\
+	bl	_dl_start					\n\
+	// returns user entry point in x0			\n\
+	mov	x21, x0						\n\
+_dl_start_user:							\n\
+	// get the original arg count				\n\
+	ldr	x1, [sp]					\n\
+	// get the argv address					\n\
+	add	x2, sp, #8					\n\
+	// get _dl_skip_args to see if we were			\n\
+	// invoked as an executable				\n\
+	adrp	x4, _dl_skip_args				\n\
+        ldr	w4, [x4, #:lo12:_dl_skip_args]			\n\
+	// do we need to adjust argc/argv			\n\
+        cmp	w4, 0						\n\
+	beq	.L_done_stack_adjust				\n\
+	// subtract _dl_skip_args from original arg count	\n\
+	sub	x1, x1, x4					\n\
+	// store adjusted argc back to stack			\n\
+	str	x1, [sp]					\n\
+	// find the first unskipped argument			\n\
+	mov	x3, x2						\n\
+	add	x4, x2, x4, lsl #3				\n\
+	// shuffle argv down					\n\
+1:	ldr	x5, [x4], #8					\n\
+	str	x5, [x3], #8					\n\
+	cmp	x5, #0						\n\
+	bne	1b						\n\
+	// shuffle envp down					\n\
+1:	ldr	x5, [x4], #8					\n\
+	str	x5, [x3], #8					\n\
+	cmp	x5, #0						\n\
+	bne	1b						\n\
+	// shuffle auxv down					\n\
+1:	ldp	x0, x5, [x4, #16]!				\n\
+	stp	x0, x5, [x3], #16				\n\
+	cmp	x0, #0						\n\
+	bne	1b						\n\
+	// Update _dl_argv					\n\
+	adrp	x3, _dl_argv					\n\
+	str	x2, [x3, #:lo12:_dl_argv]			\n\
+.L_done_stack_adjust:						\n\
+	// compute envp						\n\
+	add	x3, x2, x1, lsl #3				\n\
+	add	x3, x3, #8					\n\
+	adrp	x16, _rtld_local				\n\
+        add	x16, x16, #:lo12:_rtld_local			\n\
+        ldr	x0, [x16]					\n\
+	bl	_dl_init_internal				\n\
+	// load the finalizer function				\n\
+	adrp	x0, _dl_fini					\n\
+	add	x0, x0, #:lo12:_dl_fini				\n\
+	// jump to the user_s entry point			\n\
+	br      x21						\n\
+");
+
+#define elf_machine_type_class(type)					\
+  ((((type) == R_AARCH64_JUMP_SLOT ||					\
+     (type) == R_AARCH64_TLS_DTPMOD64 ||				\
+     (type) == R_AARCH64_TLS_DTPREL64 ||				\
+     (type) == R_AARCH64_TLS_TPREL64 ||					\
+     (type) == R_AARCH64_TLSDESC) * ELF_RTYPE_CLASS_PLT)		\
+   | (((type) == R_AARCH64_COPY) * ELF_RTYPE_CLASS_COPY))
+
+#define ELF_MACHINE_JMP_SLOT	R_AARCH64_JUMP_SLOT
+
+/* AArch64 uses RELA not REL */
+#define ELF_MACHINE_NO_REL 1
+
+static inline ElfW(Addr)
+elf_machine_fixup_plt (struct link_map *map, lookup_t t,
+		       const ElfW(Rela) *reloc,
+		       ElfW(Addr) *reloc_addr,
+		       ElfW(Addr) value)
+{
+  return *reloc_addr = value;
+}
+
+/* Return the final value of a plt relocation.  */
+static inline ElfW(Addr)
+elf_machine_plt_value (struct link_map *map,
+		       const ElfW(Rela) *reloc,
+		       ElfW(Addr) value)
+{
+  return value;
+}
+
+#endif
+
+/* Names of the architecture-specific auditing callback functions.  */
+#define ARCH_LA_PLTENTER aarch64_gnu_pltenter
+#define ARCH_LA_PLTEXIT  aarch64_gnu_pltexit
+
+#ifdef RESOLVE_MAP
+
+auto inline void
+__attribute__ ((always_inline))
+elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
+		  const ElfW(Sym) *sym, const struct r_found_version *version,
+		  void *const reloc_addr_arg, int skip_ifunc)
+{
+  ElfW(Addr) *const reloc_addr = reloc_addr_arg;
+  const unsigned int r_type = ELF64_R_TYPE (reloc->r_info);
+
+  if (__builtin_expect (r_type == R_AARCH64_RELATIVE, 0))
+      *reloc_addr = map->l_addr + reloc->r_addend;
+  else if (__builtin_expect (r_type == R_AARCH64_NONE, 0))
+      return;
+  else
+    {
+      const ElfW(Sym) *const refsym = sym;
+      struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
+      ElfW(Addr) value = sym_map == NULL ? 0 : sym_map->l_addr + sym->st_value;
+
+      if (sym != NULL
+	  && __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC)
+	  && __glibc_likely (sym->st_shndx != SHN_UNDEF)
+	  && __glibc_likely (!skip_ifunc))
+	value = elf_ifunc_invoke (value);
+
+      switch (r_type)
+	{
+	case R_AARCH64_COPY:
+	  if (sym == NULL)
+	      break;
+
+	  if (sym->st_size > refsym->st_size
+	      || (GLRO(dl_verbose) && sym->st_size < refsym->st_size))
+	    {
+	      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, strtab + refsym->st_name);
+	    }
+	  memcpy (reloc_addr_arg, (void *) value,
+		  MIN (sym->st_size, refsym->st_size));
+	  break;
+
+	case R_AARCH64_RELATIVE:
+	case R_AARCH64_GLOB_DAT:
+	case R_AARCH64_JUMP_SLOT:
+	case R_AARCH64_ABS32:
+	case R_AARCH64_ABS64:
+	  *reloc_addr = value + reloc->r_addend;
+	  break;
+
+	case R_AARCH64_TLSDESC:
+	  {
+	    struct tlsdesc volatile *td =
+	      (struct tlsdesc volatile *)reloc_addr;
+#ifndef RTLD_BOOTSTRAP
+	    if (! sym)
+	      {
+		td->arg = (void*)reloc->r_addend;
+		td->entry = _dl_tlsdesc_undefweak;
+	      }
+	    else
+#endif
+	      {
+#ifndef RTLD_BOOTSTRAP
+# ifndef SHARED
+		CHECK_STATIC_TLS (map, sym_map);
+# else
+		if (!TRY_STATIC_TLS (map, sym_map))
+		  {
+		    td->arg = _dl_make_tlsdesc_dynamic
+		      (sym_map, sym->st_value + reloc->r_addend);
+		    td->entry = _dl_tlsdesc_dynamic;
+		  }
+		else
+# endif
+#endif
+		  {
+		    td->arg = (void*)(sym->st_value + sym_map->l_tls_offset
+				      + reloc->r_addend);
+		    td->entry = _dl_tlsdesc_return;
+		  }
+	      }
+	    break;
+	  }
+
+	case R_AARCH64_TLS_DTPMOD64:
+#ifdef RTLD_BOOTSTRAP
+	  *reloc_addr = 1;
+#else
+	  if (sym_map != NULL)
+	    {
+	      *reloc_addr = sym_map->l_tls_modid;
+	    }
+#endif
+	  break;
+
+	case R_AARCH64_TLS_DTPREL64:
+	  if (sym)
+	    *reloc_addr = sym->st_value + reloc->r_addend;
+	  break;
+
+	case R_AARCH64_TLS_TPREL64:
+	  if (sym)
+	    {
+	      CHECK_STATIC_TLS (map, sym_map);
+	      *reloc_addr =
+		sym->st_value + reloc->r_addend + sym_map->l_tls_offset;
+	    }
+	  break;
+
+	case R_AARCH64_IRELATIVE:
+	  value = map->l_addr + reloc->r_addend;
+	  value = elf_ifunc_invoke (value);
+	  *reloc_addr = value;
+	  break;
+
+	default:
+	  _dl_reloc_bad_type (map, r_type, 0);
+	  break;
+	}
+    }
+}
+
+inline void
+__attribute__ ((always_inline))
+elf_machine_rela_relative (ElfW(Addr) l_addr,
+			   const ElfW(Rela) *reloc,
+			   void *const reloc_addr_arg)
+{
+  ElfW(Addr) *const reloc_addr = reloc_addr_arg;
+  *reloc_addr = l_addr + reloc->r_addend;
+}
+
+inline void
+__attribute__ ((always_inline))
+elf_machine_lazy_rel (struct link_map *map,
+		      ElfW(Addr) l_addr,
+		      const ElfW(Rela) *reloc,
+		      int skip_ifunc)
+{
+  ElfW(Addr) *const reloc_addr = (void *) (l_addr + reloc->r_offset);
+  const unsigned int r_type = ELF64_R_TYPE (reloc->r_info);
+  /* Check for unexpected PLT reloc type.  */
+  if (__builtin_expect (r_type == R_AARCH64_JUMP_SLOT, 1))
+    {
+      if (__builtin_expect (map->l_mach.plt, 0) == 0)
+	*reloc_addr += l_addr;
+      else
+	*reloc_addr = map->l_mach.plt;
+    }
+  else if (__builtin_expect (r_type == R_AARCH64_TLSDESC, 1))
+    {
+      struct tlsdesc volatile *td =
+	(struct tlsdesc volatile *)reloc_addr;
+
+      td->arg = (void*)reloc;
+      td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)])
+			  + map->l_addr);
+    }
+  else if (__glibc_unlikely (r_type == R_AARCH64_IRELATIVE))
+    {
+      ElfW(Addr) value = map->l_addr + reloc->r_addend;
+      if (__glibc_likely (!skip_ifunc))
+	value = elf_ifunc_invoke (value);
+      *reloc_addr = value;
+    }
+  else
+    _dl_reloc_bad_type (map, r_type, 1);
+}
+
+#endif