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-rw-r--r--sysdeps/sparc/dl-machine.h250
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diff --git a/sysdeps/sparc/dl-machine.h b/sysdeps/sparc/dl-machine.h
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+/* Machine-dependent ELF dynamic relocation inline functions. SPARC version.
+Copyright (C) 1996 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., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#define ELF_MACHINE_NAME "sparc"
+
+#include <assert.h>
+#include <string.h>
+#include <link.h>
+
+
+/* Some SPARC opcodes we need to use for self-modifying code. */
+#define OPCODE_NOP 0x01000000 /* nop */
+#define OPCODE_CALL 0x04000000 /* 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)
+{
+ switch (e_machine)
+ {
+ case EM_SPARC:
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+
+/* Return the run-time address of the _GLOBAL_OFFSET_TABLE_.
+ Must be inlined in a function which uses global data. */
+static inline Elf32_Addr *
+elf_machine_got (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)
+{
+ Elf32_Addr addr;
+???
+ return addr;
+}
+
+/* The `subl' insn above will contain an R_68K_RELATIVE relocation
+ entry intended to insert the run-time address of the label `here'.
+ This will be the first relocation in the text of the dynamic
+ linker; we skip it to avoid trying to modify read-only text in this
+ early stage. */
+#define ELF_MACHINE_BEFORE_RTLD_RELOC(dynamic_info) \
+ ((dynamic_info)[DT_RELA]->d_un.d_ptr += sizeof (Elf32_Rela), \
+ (dynamic_info)[DT_RELASZ]->d_un.d_val -= sizeof (Elf32_Rela))
+
+/* 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,
+ Elf32_Addr (*resolve) (const Elf32_Sym **ref,
+ Elf32_Addr reloc_addr,
+ int noplt))
+{
+ Elf32_Addr *const reloc_addr = (void *) (map->l_addr + reloc->r_offset);
+ Elf32_Addr loadbase;
+
+ switch (ELF32_R_TYPE (reloc->r_info))
+ {
+ case R_SPARC_COPY:
+ loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
+ memcpy (reloc_addr, (void *) (loadbase + sym->st_value), sym->st_size);
+ break;
+ case R_SPARC_GLOB_DAT:
+ case R_SPARC_32:
+ loadbase = (resolve ? (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0) :
+ /* RESOLVE is null during bootstrap relocation. */
+ map->l_addr);
+ *reloc_addr = ((sym ? (loadbase + sym->st_value) : 0)
+ + reloc->r_addend);
+ break;
+ case R_SPARC_JMP_SLOT:
+ loadbase = (resolve ? (*resolve) (&sym, (Elf32_Addr) reloc_addr, 1) :
+ /* RESOLVE is null during bootstrap relocation. */
+ map->l_addr);
+ {
+ Elf32_Addr value = ((sym ? (loadbase + sym->st_value) : 0)
+ + reloc->r_addend);
+ reloc_addr[1] = OPCODE_SETHI | (value >> 10);
+ reloc_addr[2] = OPCODE_JMP_G1 | (value & 0x3ff);
+ }
+ break;
+ case R_SPARC_8:
+ loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
+ *(char *) reloc_addr = ((sym ? (loadbase + sym->st_value) : 0)
+ + reloc->r_addend);
+ break;
+ case R_SPARC_16:
+ loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
+ *(short *) reloc_addr = ((sym ? (loadbase + sym->st_value) : 0)
+ + reloc->r_addend);
+ break;
+ case R_SPARC_32:
+ loadbase = (resolve ? (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0) :
+ /* RESOLVE is null during bootstrap relocation. */
+ map->l_addr);
+ break;
+ case R_SPARC_RELATIVE:
+ *reloc_addr = map->l_addr + reloc->r_addend;
+ break;
+ case R_SPARC_DISP8:
+ loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
+ *(char *) reloc_addr = ((sym ? (loadbase + sym->st_value) : 0)
+ + reloc->r_addend
+ - (Elf32_Addr) reloc_addr);
+ break;
+ case R_SPARC_DISP16:
+ loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
+ *(short *) reloc_addr = ((sym ? (loadbase + sym->st_value) : 0)
+ + reloc->r_addend
+ - (Elf32_Addr) reloc_addr);
+ break;
+ case R_SPARC_DISP32:
+ loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
+ *reloc_addr = ((sym ? (loadbase + sym->st_value) : 0)
+ + reloc->r_addend
+ - (Elf32_Addr) reloc_addr);
+ 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;
+ }
+}
+
+/* Nonzero iff TYPE describes relocation of a PLT entry, so
+ PLT entries should not be allowed to define the value. */
+#define elf_machine_pltrel_p(type) ((type) == R_SPARC_JMP_SLOT)
+
+/* The SPARC never uses Elf32_Rel relocations. */
+#define ELF_MACHINE_NO_REL 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 void
+elf_machine_runtime_setup (struct link_map *l, int lazy)
+{
+ 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] = l;
+ }
+
+ /* 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:
+ | 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 (???)