iris6.h (DWARF_FRAME_RETURN_COLUMN): Redefine to match what the system unwinder expects.

	* config/mips/iris6.h (DWARF_FRAME_RETURN_COLUMN): Redefine to
	match what the system unwinder expects.
	* config/mips/mips.c (mips_frame_set): If we're saving the return
	address register and the dwarf return address column number differs
	from the hard register number, adjust the note reg to refer to the
	former.

From-SVN: r97617

gcc/ChangeLog

+2005-04-05  Olivier Hainque  <hainque@adacore.com>
+	
+	* config/mips/iris6.h (DWARF_FRAME_RETURN_COLUMN): Redefine to
+	match what the system unwinder expects.
+	* config/mips/mips.c (mips_frame_set): If we're saving the return
+	address register and the dwarf return address column number differs
+	from the hard register number, adjust the note reg to refer to the
+	former.
+
 2004-04-05  Richard Sandiford  <rsandifo@redhat.com>
 
 	* config/mn10300/mn10300-protos.h (mn10300_override_options): Declare.

gcc/config/mips/iris6.h

@@ -38,6 +38,11 @@ Boston, MA 02111-1307, USA.  */
    compiling -g.  This guarantees that we can unwind the stack.  */
 #define DWARF2_FRAME_INFO 1
 
+/* The system unwinder in libexc requires a specific dwarf return address
+   column to work.  */
+#undef  DWARF_FRAME_RETURN_COLUMN
+#define DWARF_FRAME_RETURN_COLUMN (FP_REG_LAST + 1)
+
 #undef MACHINE_TYPE
 #define MACHINE_TYPE "SGI running IRIX 6.x"
 

gcc/config/mips/mips.c

@@ -6276,8 +6276,18 @@ mips_set_frame_expr (rtx frame_pattern)
 static rtx
 mips_frame_set (rtx mem, rtx reg)
 {
-  rtx set = gen_rtx_SET (VOIDmode, mem, reg);
+  rtx set;
+
+  /* If we're saving the return address register and the dwarf return
+     address column differs from the hard register number, adjust the
+     note reg to refer to the former.  */
+  if (REGNO (reg) == GP_REG_FIRST + 31
+      && DWARF_FRAME_RETURN_COLUMN != GP_REG_FIRST + 31)
+    reg = gen_rtx_REG (GET_MODE (reg), DWARF_FRAME_RETURN_COLUMN);
+
+  set = gen_rtx_SET (VOIDmode, mem, reg);
   RTX_FRAME_RELATED_P (set) = 1;
+
   return set;
 }