flow.c (update_life_info): Zap life info after cleanup_cfg.

        * flow.c (update_life_info): Zap life info after cleanup_cfg.
        (regno_uninitialized): Use correct live at function entry set.
        (regno_clobbered_at_setjmp): Likewise.

From-SVN: r62172

1 files changed, 12 insertions, 2 deletions

diff --git a/gcc/flow.c b/gcc/flow.c
index 5e51818..24f8691 100644
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -693,6 +693,16 @@ update_life_info (blocks, extent, prop_flags)
 	     partial improvement (see MAX_MEM_SET_LIST_LEN usage).
 	     Further improvement may be possible.  */
 	  cleanup_cfg (CLEANUP_EXPENSIVE);
+
+	  /* Zap the life information from the last round.  If we don't 
+	     do this, we can wind up with registers that no longer appear
+	     in the code being marked live at entry, which twiggs bogus
+	     warnings from regno_uninitialized.  */
+	  FOR_EACH_BB (bb)
+	    {
+	      CLEAR_REG_SET (bb->global_live_at_start);
+	      CLEAR_REG_SET (bb->global_live_at_end);
+	    }
 	}
 
       /* If asked, remove notes from the blocks we'll update.  */
@@ -2379,7 +2389,7 @@ regno_uninitialized (regno)
 	      || FUNCTION_ARG_REGNO_P (regno))))
     return 0;
 
-  return REGNO_REG_SET_P (ENTRY_BLOCK_PTR->next_bb->global_live_at_start, regno);
+  return REGNO_REG_SET_P (ENTRY_BLOCK_PTR->global_live_at_end, regno);
 }
 
 /* 1 if register REGNO was alive at a place where `setjmp' was called
@@ -2394,7 +2404,7 @@ regno_clobbered_at_setjmp (regno)
     return 0;
 
   return ((REG_N_SETS (regno) > 1
-	   || REGNO_REG_SET_P (ENTRY_BLOCK_PTR->next_bb->global_live_at_start, regno))
+	   || REGNO_REG_SET_P (ENTRY_BLOCK_PTR->global_live_at_end, regno))
 	  && REGNO_REG_SET_P (regs_live_at_setjmp, regno));
 }