gdb call0 patch

0001-XTensa-call0-ABI-Reference-register-cache.patch

From b08ec678a9e4cd3cb8d41979c4049315004a94dd Mon Sep 17 00:00:00 2001
From: Angus Gratton <gus@projectgus.com>
Date: Wed, 6 May 2015 11:19:42 +1000
Subject: [PATCH] XTensa call0 ABI: Reference register cache from a0 when
 unwinding

Fixes bug where wrong Frame Pointer value was read during backtrace,
leading to corrupt stack traces.
---
 gdb/xtensa-tdep.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/gdb/xtensa-tdep.c b/gdb/xtensa-tdep.c
index a66d00a..eacd656 100644
--- a/gdb/xtensa-tdep.c
+++ b/gdb/xtensa-tdep.c
@@ -1505,10 +1505,11 @@ xtensa_frame_prev_register (struct frame_info *this_frame,
     }
   else /* Call0 ABI.  */
     {
-      int reg = (regnum >= gdbarch_tdep (gdbarch)->ar_base
-		&& regnum <= (gdbarch_tdep (gdbarch)->ar_base
+      int reg = (regnum >= gdbarch_tdep (gdbarch)->a0_base
+		&& regnum <= (gdbarch_tdep (gdbarch)->a0_base
 			       + C0_NREGS))
-		  ? regnum - gdbarch_tdep (gdbarch)->ar_base : regnum;
+		  ? regnum - gdbarch_tdep (gdbarch)->a0_base : regnum;
+
 
       if (reg < C0_NREGS)
 	{
-- 
2.1.4