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-rw-r--r--sysdeps/nios2/dl-machine.h335
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diff --git a/sysdeps/nios2/dl-machine.h b/sysdeps/nios2/dl-machine.h
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+/* Machine-dependent ELF dynamic relocation inline functions.  Nios II version.
+   Copyright (C) 1995-2015 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 "nios2"
+
+#include <string.h>
+#include <link.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_ALTERA_NIOS2;
+}
+
+
+/* Return the link-time address of _DYNAMIC.  Conveniently, this is the
+   first element of the GOT.  */
+static inline Elf32_Addr
+elf_machine_dynamic (void)
+{
+  Elf32_Addr *dynamic;
+  int tmp;
+  asm ("nextpc\t%0\n\t"
+       "1: movhi\t%1, %%hiadj(_GLOBAL_OFFSET_TABLE_ - 1b)\n\t"
+       "addi\t%1, %1, %%lo(_GLOBAL_OFFSET_TABLE_ - 1b)\n\t"
+       "add\t%0, %0, %1\n"
+       : "=r" (dynamic), "=r" (tmp));
+  return *dynamic;
+}
+
+
+/* Return the run-time load address of the shared object.  */
+static inline Elf32_Addr
+elf_machine_load_address (void)
+{
+  Elf32_Addr result;
+  int tmp;
+  asm ("nextpc\t%0\n\t"
+       "1: movhi\t%1, %%hiadj(1b)\n\t"
+       "addi\t%1, %1, %%lo(1b)\n\t"
+       "sub\t%0, %0, %1\n"
+       : "=r" (result), "=r" (tmp));
+  return result;
+}
+
+/* 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)
+{
+  extern void _dl_runtime_resolve (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 load r15 with
+         an offset into the .got section, load r14 with
+	 _GLOBAL_OFFSET_TABLE_[1], and then jump to _GLOBAL_OFFSET_TABLE[2].
+      */
+      Elf32_Addr *got = (Elf32_Addr *) D_PTR (l, l_info[DT_PLTGOT]);
+      got[1] = (Elf32_Addr) l;	/* Identify this shared object.  */
+
+      /* 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;
+}
+
+/* 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\
+        /* At start time, all the args are on the stack.  */\n\
+        mov r4, sp\n\
+\n\
+        /* Start the calculation of the GOT pointer.  */\n\
+        nextpc r22\n\
+1:      movhi r8, %hiadj(_gp_got - 1b)\n\
+        addi r8, r8, %lo(_gp_got - 1b)\n\
+\n\
+        /* Figure out where _dl_start will need to return to.  */\n\
+        movhi ra, %hiadj(2f - 1b)\n\
+        addi ra, ra, %lo(2f - 1b)\n\
+        add ra, ra, r22\n\
+\n\
+        /* Finish the calculation of the GOT pointer.  */\n\
+        add r22, r22, r8\n\
+\n\
+        br _dl_start\n\
+\n\
+        /* Save the returned user entry point.  */\n\
+2:      mov r16, r2\n\
+\n\
+        /* Initialize gp.  */\n\
+        ldw r4, %got(_rtld_local)(r22)\n\
+        ldw r4, 0(r4)\n\
+        ldw r8, %call(_dl_nios2_get_gp_value)(r22)\n\
+        callr r8\n\
+        mov gp, r2\n\
+\n\
+        /* Find the number of arguments to skip.  */\n\
+        ldw r8, %got(_dl_skip_args)(r22)\n\
+        ldw r8, 0(r8)\n\
+\n\
+        /* Find the main_map from the GOT.  */\n\
+        ldw r4, %got(_rtld_local)(r22)\n\
+        ldw r4, 0(r4)\n\
+\n\
+        /* Find argc.  */\n\
+        ldw r5, 0(sp)\n\
+        sub r5, r5, r8\n\
+        stw r5, 0(sp)\n\
+\n\
+        /* Find the first unskipped argument.  */\n\
+        slli r8, r8, 2\n\
+        addi r6, sp, 4\n\
+        add r9, r6, r8\n\
+        mov r10, r6\n\
+\n\
+        /* Shuffle argv down.  */\n\
+3:      ldw r11, 0(r9)\n\
+        stw r11, 0(r10)\n\
+        addi r9, r9, 4\n\
+        addi r10, r10, 4\n\
+        bne r11, zero, 3b\n\
+\n\
+        /* Shuffle envp down.  */\n\
+        mov r7, r10\n\
+4:      ldw r11, 0(r9)\n\
+        stw r11, 0(r10)\n\
+        addi r9, r9, 4\n\
+        addi r10, r10, 4\n\
+        bne r11, zero, 4b\n\
+\n\
+        /* Shuffle auxv down.  */\n\
+5:      ldw r11, 4(r9)\n\
+        stw r11, 4(r10)\n\
+        ldw r11, 0(r9)\n\
+        stw r11, 0(r10)\n\
+        addi r9, r9, 8\n\
+        addi r10, r10, 8\n\
+        bne r11, zero, 5b\n\
+\n\
+        /* Update _dl_argv.  */\n\
+        ldw r2, %got(_dl_argv)(r22)\n\
+        stw r6, 0(r2)\n\
+\n\
+        /* Call _dl_init through the PLT.  */\n\
+        ldw r8, %call(_dl_init)(r22)\n\
+        callr r8\n\
+\n\
+        /* Find the finalization function.  */\n\
+        ldw r4, %got(_dl_fini)(r22)\n\
+\n\
+        /* Jump to the user's entry point.  */\n\
+        jmp r16\n\
+");
+
+/* 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_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_NIOS2_JUMP_SLOT				\
+     || (type) == R_NIOS2_TLS_DTPMOD				\
+     || (type) == R_NIOS2_TLS_DTPREL				\
+     || (type) == R_NIOS2_TLS_TPREL) * ELF_RTYPE_CLASS_PLT)	\
+   | (((type) == R_NIOS2_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_NIOS2_JUMP_SLOT
+
+/* The Nios II never uses Elf32_Rel relocations.  */
+#define ELF_MACHINE_NO_REL 1
+#define ELF_MACHINE_NO_RELA 0
+
+/* Fixup a PLT entry to bounce directly to the function at VALUE.  */
+
+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.  */
+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 nios2_gnu_pltenter
+#define ARCH_LA_PLTEXIT nios2_gnu_pltexit
+
+#endif /* dl_machine_h */
+
+#ifdef RESOLVE_MAP
+
+/* 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 ElfW(Rela) *reloc,
+                  const ElfW(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 (__glibc_unlikely (r_type == R_NIOS2_RELATIVE))
+    *reloc_addr = map->l_addr + reloc->r_addend;
+  else if (__glibc_unlikely (r_type == R_NIOS2_NONE))
+    return;
+  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_NIOS2_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_NIOS2_GLOB_DAT:
+	case R_NIOS2_JUMP_SLOT:
+# ifdef RTLD_BOOTSTRAP
+          /* Fix weak undefined references.  */
+          if (sym != NULL && sym->st_value == 0)
+            *reloc_addr = 0;
+          else
+# endif
+            *reloc_addr = value;
+          break;
+#ifndef RTLD_BOOTSTRAP
+        case R_NIOS2_TLS_DTPMOD:
+          /* 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_NIOS2_TLS_DTPREL:
+          *reloc_addr = reloc->r_addend + TLS_DTPREL_VALUE(sym);
+          break;
+
+        case R_NIOS2_TLS_TPREL:
+          if (sym != NULL)
+            {
+              CHECK_STATIC_TLS (map, sym_map);
+              *reloc_addr = reloc->r_addend + TLS_TPREL_VALUE(sym_map, sym);
+            }
+          break;
+#endif
+        case R_NIOS2_BFD_RELOC_32:
+          *reloc_addr = value + reloc->r_addend;
+          break;
+
+	default:
+          _dl_reloc_bad_type (map, r_type, 0);
+          break;
+	}
+    }
+}
+
+auto inline void __attribute__((always_inline))
+elf_machine_rela_relative (ElfW(Addr) l_addr, const ElfW(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,
+		      ElfW(Addr) l_addr, const ElfW(Rela) *reloc,
+		      int skip_ifunc)
+{
+  Elf32_Addr *const reloc_addr = (void *) (l_addr + reloc->r_offset);
+  if (ELF32_R_TYPE (reloc->r_info) == R_NIOS2_JUMP_SLOT)
+    *reloc_addr += l_addr;
+  else
+    _dl_reloc_bad_type (map, ELF32_R_TYPE (reloc->r_info), 1);
+}
+
+#endif /* RESOLVE_MAP */