Squashed 'third_party/elfutils/' content from commit 555e15e

Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/backends/arm_cfi.c b/backends/arm_cfi.c
new file mode 100644
index 0000000..971a1fc
--- /dev/null
+++ b/backends/arm_cfi.c
@@ -0,0 +1,90 @@
+/* arm ABI-specified defaults for DWARF CFI.
+   Copyright (C) 2013 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils 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
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <dwarf.h>
+
+#define BACKEND arm_
+#include "libebl_CPU.h"
+
+
+/* ABI-specified state of DWARF CFI based on:
+
+   "DWARF for the ARM Architecture ABI r2.09"
+http://infocenter.arm.com/help/topic/com.arm.doc.ihi0040b/IHI0040B_aadwarf.pdf
+
+   "Procedure Call Standard for the ARM Architecture ABI r2.09"
+http://infocenter.arm.com/help/topic/com.arm.doc.ihi0042e/IHI0042E_aapcs.pdf
+*/
+
+int
+arm_abi_cfi (Ebl *ebl __attribute__ ((unused)), Dwarf_CIE *abi_info)
+{
+  static const uint8_t abi_cfi[] =
+    {
+      /* The initial Canonical Frame Address is the value of the
+         Stack Pointer (r13) as setup in the previous frame. */
+      DW_CFA_def_cfa, ULEB128_7 (13), ULEB128_7 (0),
+
+      /* The Stack Pointer (r13) is restored from CFA address by default.  */
+      DW_CFA_val_offset, ULEB128_7 (13), ULEB128_7 (0),
+
+#define SV(n) DW_CFA_same_value, ULEB128_7 (n)
+      /* Callee-saved regs r4-r8, r10, r11.  */
+      SV (4), SV (5), SV (6), SV (7), SV (8), SV (10), SV (11),
+
+      /* The link register contains the return address setup by caller.  */
+      SV (14),
+      DW_CFA_register, ULEB128_7 (15), ULEB128_7 (14), /* pc = lr */
+#undef SV
+
+      /* VFP S16-S31/D8-D15/Q4-Q7 are callee saved.
+         And uleb128 encoded with two bytes.  */
+#define ULEB128_8_2(x) ((x & 0x7f) | 0x80), 0x02
+#define SV(n) DW_CFA_same_value, ULEB128_8_2 (n)
+      SV (264), SV (265), SV (266), SV (267),
+      SV (268), SV (269), SV (270), SV (271),
+
+      /* XXX Note: registers intentionally unused by the program,
+	 for example as a consequence of the procedure call standard
+	 should be initialized as if by DW_CFA_same_value.  */
+    };
+#undef ULEB128_8_2
+#undef SV
+
+  abi_info->initial_instructions = abi_cfi;
+  abi_info->initial_instructions_end = &abi_cfi[sizeof abi_cfi];
+  abi_info->data_alignment_factor = 4;
+
+  abi_info->return_address_register = 15; /* pc.  */
+
+  return 0;
+}