[PATCH 1/3] rs6000: rs6000_dbx_register_number for fp/ap/mq

[Segher Boessenkool]

The frame pointer and the argument pointer aren't real registers.  MQ
was a register on old POWER.  All three are still used as arguments to
rs6000_dbx_register_number during initialisation.  If we handle them
explicitly we can do a gcc_unreachable to catch other unexpected
registers.

Tested on powerpc64-linux {-m32,-m64} and on powerpc64le-linux;
installing on trunk.


Segher


2019-05-06  Segher Boessenkool  <seg...@kernel.crashing.org>

        * config/rs6000/rs6000.c (rs6000_dbx_register_number): Handle
        FRAME_POINTER_REGNUM, ARG_POINTER_REGNUM, and 64 (which was MQ).

--
 gcc/config/rs6000/rs6000.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index c75fd86..6f46fdd 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -36305,7 +36305,15 @@ rs6000_dbx_register_number (unsigned int regno, 
unsigned int format)
       if (regno == TEXASR_REGNO)
        return 230;
 
-      return regno;
+      /* These do not make much sense.  */
+      if (regno == FRAME_POINTER_REGNUM)
+       return 111;
+      if (regno == ARG_POINTER_REGNUM)
+       return 67;
+      if (regno == 64)
+       return 100;
+
+      gcc_unreachable ();
 #endif
     }
 
@@ -36337,7 +36345,14 @@ rs6000_dbx_register_number (unsigned int regno, 
unsigned int format)
   if (regno == TEXASR_REGNO)
     return 116;
 
-  return regno;
+  if (regno == FRAME_POINTER_REGNUM)
+    return 111;
+  if (regno == ARG_POINTER_REGNUM)
+    return 67;
+  if (regno == 64)
+    return 64;
+
+  gcc_unreachable ();
 }
 
 /* target hook eh_return_filter_mode */
-- 
1.8.3.1