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authorDavid S. Miller <davem@davemloft.net>2010-02-10 07:42:17 -0800
committerUlrich Drepper <drepper@redhat.com>2010-02-10 07:42:17 -0800
commit311927f1bd58b6e2b36e3bbb83bbc4dbdb507155 (patch)
treeeae31d6ce51c8a6f279b6ad43787a4ffbc3a7a5f /sysdeps/sparc/sparc32/dl-plt.h
parent57e065ae1eda898a42d9cb8e2ea344290d05578c (diff)
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Sparc STT_GNU_IFUNC support
Diffstat (limited to 'sysdeps/sparc/sparc32/dl-plt.h')
-rw-r--r--sysdeps/sparc/sparc32/dl-plt.h62
1 files changed, 62 insertions, 0 deletions
diff --git a/sysdeps/sparc/sparc32/dl-plt.h b/sysdeps/sparc/sparc32/dl-plt.h
new file mode 100644
index 0000000000..edcc5c1374
--- /dev/null
+++ b/sysdeps/sparc/sparc32/dl-plt.h
@@ -0,0 +1,62 @@
+/* PLT fixups.  Sparc 32-bit version.
+   Copyright (C) 1996-2003, 2004, 2005, 2006, 2007, 2010
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+/* Some SPARC opcodes we need to use for self-modifying code.  */
+#define OPCODE_NOP	0x01000000 /* nop */
+#define OPCODE_CALL	0x40000000 /* 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_SP	0x9de3bfa8 /* save %sp, -(16+6)*4, %sp */
+#define OPCODE_BA	0x30800000 /* b,a ?; add PC-rel word address */
+
+static inline __attribute__ ((always_inline)) Elf32_Addr
+sparc_fixup_plt (const Elf32_Rela *reloc, Elf32_Addr *reloc_addr,
+		 Elf32_Addr value, int t, int do_flush)
+{
+  Elf32_Sword disp = value - (Elf32_Addr) reloc_addr;
+
+  if (0 && disp >= -0x800000 && disp < 0x800000)
+    {
+      /* Don't need to worry about thread safety. We're writing just one
+	 instruction.  */
+
+      reloc_addr[0] = OPCODE_BA | ((disp >> 2) & 0x3fffff);
+      if (do_flush)
+	__asm __volatile ("flush %0" : : "r"(reloc_addr));
+    }
+  else
+    {
+      /* For thread safety, write the instructions from the bottom and
+	 flush before we overwrite the critical "b,a".  This of course
+	 need not be done during bootstrapping, since there are no threads.
+	 But we also can't tell if we _can_ use flush, so don't. */
+
+      reloc_addr += t;
+      reloc_addr[1] = OPCODE_JMP_G1 | (value & 0x3ff);
+      if (do_flush)
+	__asm __volatile ("flush %0+4" : : "r"(reloc_addr));
+
+      reloc_addr[0] = OPCODE_SETHI_G1 | (value >> 10);
+      if (do_flush)
+	__asm __volatile ("flush %0" : : "r"(reloc_addr));
+    }
+
+  return value;
+}