recog.c (peephole2_optimize): Split blocks when EH insns are generated in the middle...

        * recog.c (peephole2_optimize): Split blocks when EH insns are
        generated in the middle of a block.  Do global life update if
        zapped EH edges.

From-SVN: r51285

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d8103b4162b25d2a20f0071e4eb0734da347f5c6..cb4a988bec023faed2af056a4e3e378e75cc0b25 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2002-03-24  Richard Henderson  <rth@redhat.com>
+
+       * recog.c (peephole2_optimize): Split blocks when EH insns are 
+       generated in the middle of a block.  Do global life update if
+       zapped EH edges.
+
 2002-03-24  Richard Henderson  <rth@redhat.com>
 
        * mips.c (mips_function_value): Only promote_mode for non-libcalls.

diff --git a/gcc/recog.c b/gcc/recog.c
index cb1cb666a8c3bfbdd1014f2a8da3ea650e0705e1..769c267efedd5c52ea947c502083d5a4ee195309 100644 (file)
--- a/gcc/recog.c
+++ b/gcc/recog.c
@@ -3000,8 +3000,9 @@ peephole2_optimize (dump_file)
   int i, b;
 #ifdef HAVE_conditional_execution
   sbitmap blocks;
-  int changed;
+  bool changed;
 #endif
+  bool do_cleanup_cfg = false;
 
   /* Initialize the regsets we're going to use.  */
   for (i = 0; i < MAX_INSNS_PER_PEEP2 + 1; ++i)
@@ -3011,7 +3012,7 @@ peephole2_optimize (dump_file)
 #ifdef HAVE_conditional_execution
   blocks = sbitmap_alloc (n_basic_blocks);
   sbitmap_zero (blocks);
-  changed = 0;
+  changed = false;
 #else
   count_or_remove_death_notes (NULL, 1);
 #endif
@@ -3137,20 +3138,46 @@ peephole2_optimize (dump_file)
                                                REG_EH_REGION, NULL_RTX)))
                    {
                      rtx x;
+                     edge eh_edge;
+
+                     for (eh_edge = bb->succ; eh_edge
+                          ; eh_edge = eh_edge->succ_next)
+                       if (eh_edge->flags & EDGE_EH)
+                         break;
+
                      for (x = NEXT_INSN (peep2_insn_data[i].insn);
                           x != NEXT_INSN (try); x = NEXT_INSN (x))
                        if (GET_CODE (x) == CALL_INSN
                            || (flag_non_call_exceptions
                                && may_trap_p (PATTERN (x))))
-                         REG_NOTES (x)
-                           = gen_rtx_EXPR_LIST (REG_EH_REGION,
-                                                XEXP (note, 0),
-                                                REG_NOTES (x));
+                         {
+                           REG_NOTES (x)
+                             = gen_rtx_EXPR_LIST (REG_EH_REGION,
+                                                  XEXP (note, 0),
+                                                  REG_NOTES (x));
+
+                           if (x != bb->end && eh_edge)
+                             {
+                               edge nfte = split_block (bb, x);
+                               edge nehe = make_edge (nfte->src, eh_edge->dest,
+                                                      eh_edge->flags);
+                               nehe->probability = eh_edge->probability;
+                               nfte->probability
+                                 = REG_BR_PROB_BASE - nehe->probability;
+
+                               do_cleanup_cfg |= purge_dead_edges (nfte->dest);
+#ifdef HAVE_conditional_execution
+                               SET_BIT (blocks, nfte->dest->index);
+                               changed = true;
+#endif
+                               bb = nfte->src;
+                             }
+                         }
+
+                     /* Converting possibly trapping insn to non-trapping is
+                        possible.  Zap dummy outgoing edges.  */
+                     do_cleanup_cfg |= purge_dead_edges (bb);
                    }
-                 /* Converting possibly trapping insn to non-trapping is
-                    possible.  Zap dummy outgoing edges.  */
-                 if (try == bb->end)
-                   purge_dead_edges (bb);
 
 #ifdef HAVE_conditional_execution
                  /* With conditional execution, we cannot back up the
@@ -3159,7 +3186,7 @@ peephole2_optimize (dump_file)
                     So record that we've made a modification to this
                     block and update life information at the end.  */
                  SET_BIT (blocks, b);
-                 changed = 1;
+                 changed = true;
 
                  for (i = 0; i < MAX_INSNS_PER_PEEP2 + 1; ++i)
                    peep2_insn_data[i].insn = NULL_RTX;
@@ -3205,9 +3232,20 @@ peephole2_optimize (dump_file)
     FREE_REG_SET (peep2_insn_data[i].live_before);
   FREE_REG_SET (live);
 
+  /* If we eliminated EH edges, we may be able to merge blocks.  Further,
+     we've changed global life since exception handlers are no longer
+     reachable.  */
+  if (do_cleanup_cfg)
+    {
+      cleanup_cfg (0);
+      update_life_info (0, UPDATE_LIFE_GLOBAL_RM_NOTES, PROP_DEATH_NOTES);
+    }
 #ifdef HAVE_conditional_execution
-  count_or_remove_death_notes (blocks, 1);
-  update_life_info (blocks, UPDATE_LIFE_LOCAL, PROP_DEATH_NOTES);
+  else
+    {
+      count_or_remove_death_notes (blocks, 1);
+      update_life_info (blocks, UPDATE_LIFE_LOCAL, PROP_DEATH_NOTES);
+    }
   sbitmap_free (blocks);
 #endif
 }