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-rw-r--r--sysdeps/sparc/dl-machine.h250
-rw-r--r--sysdeps/sparc/elf/start.S111
2 files changed, 361 insertions, 0 deletions
diff --git a/sysdeps/sparc/dl-machine.h b/sysdeps/sparc/dl-machine.h
new file mode 100644
index 0000000000..695b9d6af3
--- /dev/null
+++ b/sysdeps/sparc/dl-machine.h
@@ -0,0 +1,250 @@
+/* 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 (???)
diff --git a/sysdeps/sparc/elf/start.S b/sysdeps/sparc/elf/start.S
new file mode 100644
index 0000000000..6dae08bafa
--- /dev/null
+++ b/sysdeps/sparc/elf/start.S
@@ -0,0 +1,111 @@
+/* Startup code compliant to the ELF SPARC ABI.
+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.  */
+
+/* This is the canonical entry point, usually the first thing in the text
+   segment.  The SVR4/SPARC ABI (NOTE: I don't actually have it) says that
+   when the entry point runs, most registers' values are unspecified,
+   except for:
+
+   %g1		Contains a function pointer to be registered with `atexit'.
+   		This is how the dynamic linker arranges to have DT_FINI
+		functions called for shared libraries that have been loaded
+		before this code runs.
+
+   %sp		The stack contains the arguments and environment:
+   		0(%sp)			argc
+		4(%sp)			argv[0]
+		...
+		(4*argc)(%sp)		NULL
+		(4*(argc+1))(%sp)	envp[0]
+		...
+					NULL
+*/
+
+	.text
+	.align 16
+	.global _start
+_start:
+	/* %g1 contains the address of the shared library termination
+	   function, which we will register with `atexit' to be called by
+	   `exit'.  I suspect that on some systems, and when statically
+	   linked, this will not be set by anything to any function
+	   pointer; hopefully it will be zero so we don't try to call
+	   random pointers.  */
+	orcc %g1, %g0, %o0	/* Move %g1 to %o0 while testing it.  */
+	be nofini
+
+	/* In delay slot: clear the frame pointer.  The ABI suggests this
+	   be done, to mark the outermost frame obviously.  */
+	clr %fp
+
+	/* Call atexit, argument was set in %o0 above.  */
+	call atexit
+	nop
+nofini:
+
+	/* We will use some local variables in registers below.  %g1 and
+	   the %oN registers are call-clobbered, so we can't just use them.  */
+#define ARGC	%l0
+#define ARGV	%l1
+#define ENVP	%l2
+#define TMP	%l3
+
+	/* Do essential libc initialization.  In statically linked
+	   programs under the GNU Hurd, this is what sets up the
+	   arguments on the stack for the code below.  */
+	call __libc_init_first
+	sethi %hi(_environ), TMP /* In delay slot: prepare to use &_environ. */
+
+	/* Extract the arguments and environment as encoded on the stack
+	   and save them in local variables.  */
+	ld [%sp + 64], ARGC	/* After the register save area, ARGC. */
+	add %sp, 64+4, ARGV	/* Next, the ARGV elements.  */
+	/* After ARGC words that are the ARGV elements, and a zero word,
+	   are the ENVP elements.  Do ENVP = &ARGV[ARGC + 1].  */
+	add ARGC, 1, ENVP
+	sll ENVP, 2, ENVP
+	add ARGV, ENVP, ENVP
+	/* Store ENVP in the global variable `_environ'.  */
+	st [TMP + %lo(_environ)], ENVP
+
+	/* Call `_init', which is the entry point to our own `.init'
+	   section; and register with `atexit' to have `exit' call
+	   `_fini', which is the entry point to our own `.fini' section.  */
+	call _init
+	sethi %hi(_fini), TMP	/* In delay slot of call.  */
+	or TMP, %lo(_fini), %o0	/* Argument to atexit is &_fini.  */
+	call atexit
+	nop
+
+	/* Call the user's main function, and exit with its value.  */
+	mov ARGC, %o0
+	mov ARGV, %o1
+	call main
+	mov ENVP, %o2
+
+	call exit		/* This should never return.  */
+	unimp 0			/* Crash if somehow it does return.  */
+
+/* Define a symbol for the first piece of initialized data.  */
+	.data
+	.global __data_start
+__data_start:
+	.long 0
+	.weak data_start
+	data_start = __data_start