Makefile.in (reload1.o): Add dedendancy on except.h

* Makefile.in (reload1.o): Add dedendancy on except.h
        * basic-block.h (purge_all_dead_edges, purge_dead_edges): Update
        prototypes.
        * flow.c (purge_dead_edges, purge_all_dead_edges): Return bool
        indicating wehther edges has been cleaned up.
        * reload1.c: Inlucde except.h
        (fixup_abnormal_edges): Accept deleted insns.
        * toplev.c (rest_of_compilation): Purge dead edges unconditionally
        after combine.

From-SVN: r44654

gcc/ChangeLog

@@ -1,3 +1,15 @@
+2001-08-05  Jan Hubicka  <jh@suse.cz>
+
+	* Makefile.in (reload1.o): Add dedendancy on except.h
+	* basic-block.h (purge_all_dead_edges, purge_dead_edges): Update
+	prototypes.
+	* flow.c (purge_dead_edges, purge_all_dead_edges): Return bool
+	indicating wehther edges has been cleaned up.
+	* reload1.c: Inlucde except.h
+	(fixup_abnormal_edges): Accept deleted insns.
+	* toplev.c (rest_of_compilation): Purge dead edges unconditionally
+	after combine.
+
 2001-08-06  Neil Booth  <neil@daikokuya.demon.co.uk>
 
 	* cpplib.c (do_line): Correct line number after pop_buffer.

gcc/Makefile.in

@@ -1510,7 +1510,8 @@ reload.o : reload.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) flags.h output.h $(EXPR_H)
    function.h real.h toplev.h $(TM_P_H)
 reload1.o : reload1.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) real.h flags.h $(EXPR_H) \
    reload.h $(REGS_H) hard-reg-set.h insn-config.h \
-   $(BASIC_BLOCK_H) $(RECOG_H) output.h function.h toplev.h cselib.h $(TM_P_H)
+   $(BASIC_BLOCK_H) $(RECOG_H) output.h function.h toplev.h cselib.h $(TM_P_H) \
+   except.h
 caller-save.o : caller-save.c $(CONFIG_H) $(SYSTEM_H) $(RTL_H) flags.h \
    $(REGS_H) hard-reg-set.h insn-config.h $(BASIC_BLOCK_H) function.h \
    $(RECOG_H) reload.h $(EXPR_H) toplev.h $(TM_P_H)

gcc/basic-block.h

@@ -615,8 +615,8 @@ extern basic_block redirect_edge_and_branch_force PARAMS ((edge, basic_block));
 extern bool redirect_edge_and_branch	PARAMS ((edge, basic_block));
 extern rtx block_label			PARAMS ((basic_block));
 extern bool forwarder_block_p		PARAMS ((basic_block));
-extern void purge_all_dead_edges	PARAMS ((void));
+extern bool purge_all_dead_edges	PARAMS ((void));
-extern void purge_dead_edges		PARAMS ((basic_block));
+extern bool purge_dead_edges		PARAMS ((basic_block));
 extern void find_sub_basic_blocks	PARAMS ((basic_block));
 
 

gcc/flow.c

@@ -10187,26 +10187,28 @@ init_flow ()
 }
 
 /* Assume that the preceeding pass has possibly eliminated jump instructions
-   or converted the unconditional jumps.  Eliminate the edges from CFG.  */
+   or converted the unconditional jumps.  Eliminate the edges from CFG.
+   Return true if any edges are eliminated.  */
 
-void
+bool
 purge_dead_edges (bb)
      basic_block bb;
 {
   edge e, next;
   rtx insn = bb->end;
+  bool purged = false;
+
   if (GET_CODE (insn) == JUMP_INSN && !simplejump_p (insn))
-    return;
+    return false;
   if (GET_CODE (insn) == JUMP_INSN)
     {
-      int removed = 0;
       rtx note;
       edge b,f;
       /* We do care only about conditional jumps and simplejumps.  */
       if (!any_condjump_p (insn)
 	  && !returnjump_p (insn)
 	  && !simplejump_p (insn))
-	return;
+	return false;
       for (e = bb->succ; e; e = next)
 	{
 	  next = e->succ_next;
@@ -10221,15 +10223,15 @@ purge_dead_edges (bb)
 	  if (e->dest == EXIT_BLOCK_PTR
 	      && returnjump_p (insn))
 	    continue;
-	  removed = 1;
+	  purged = true;
 	  remove_edge (e);
 	}
-      if (!bb->succ || !removed)
+      if (!bb->succ || !purged)
-	return;
+	return false;
       if (rtl_dump_file)
 	fprintf (rtl_dump_file, "Purged edges from bb %i\n", bb->index);
       if (!optimize)
-	return;
+	return purged;
 
       /* Redistribute probabilities.  */
       if (!bb->succ->succ_next)
@@ -10241,7 +10243,7 @@ purge_dead_edges (bb)
 	{
 	  note = find_reg_note (insn, REG_BR_PROB, NULL);
 	  if (!note)
-	    return;
+	    return purged;
 	  b = BRANCH_EDGE (bb);
 	  f = FALLTHRU_EDGE (bb);
 	  b->probability = INTVAL (XEXP (note, 0));
@@ -10249,8 +10251,22 @@ purge_dead_edges (bb)
 	  b->count = bb->count * b->probability / REG_BR_PROB_BASE;
 	  f->count = bb->count * f->probability / REG_BR_PROB_BASE;
 	}
-      return;
+      return purged;
     }
+
+  /* Cleanup abnormal edges caused by throwing insns that have been
+     eliminated.  */
+  if (! can_throw_internal (bb->end))
+    for (e = bb->succ; e; e = next)
+      {
+	next = e->succ_next;
+	if (e->flags & EDGE_EH)
+	  {
+	    remove_edge (e);
+	    purged = true;
+	  }
+      }
+
   /* If we don't see a jump insn, we don't know exactly why the block would
      have been broken at this point.  Look for a simple, non-fallthru edge,
      as these are only created by conditional branches.  If we find such an
@@ -10259,12 +10275,12 @@ purge_dead_edges (bb)
   for (e = bb->succ; e && (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU));
        e = e->succ_next);
   if (!e)
-    return;
+    return purged;
   for (e = bb->succ; e; e = next)
     {
       next = e->succ_next;
       if (!(e->flags & EDGE_FALLTHRU))
-	remove_edge (e);
+	remove_edge (e), purged = true;
     }
   if (!bb->succ || bb->succ->succ_next)
     abort ();
@@ -10274,15 +10290,19 @@ purge_dead_edges (bb)
   if (rtl_dump_file)
     fprintf (rtl_dump_file, "Purged non-fallthru edges from bb %i\n",
 	     bb->index);
-  return;
+  return purged;
 }
 
-/* Search all basic blocks for potentionally dead edges and purge them.  */
+/* Search all basic blocks for potentionally dead edges and purge them.
   
-void
+   Return true ifif some edge has been elliminated.
+ */
+
+bool
 purge_all_dead_edges ()
 {
-  int i;
+  int i, purged = false;
   for (i = 0; i < n_basic_blocks; i++)
-    purge_dead_edges (BASIC_BLOCK (i));
+    purged |= purge_dead_edges (BASIC_BLOCK (i));
+  return purged;
 }

gcc/reload1.c

@@ -39,6 +39,7 @@ Boston, MA 02111-1307, USA.  */
 #include "cselib.h"
 #include "real.h"
 #include "toplev.h"
+#include "except.h"
 
 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
@@ -9506,7 +9507,11 @@ fixup_abnormal_edges ()
 	  for (e = bb->succ; e; e = e->succ_next)
 	    if (e->flags & EDGE_FALLTHRU)
 	      break;
-	  while (GET_CODE (insn) == INSN && !can_throw_internal (insn))
+	  /* Get past the new insns generated. Allow notes, as the insns may
+	     be already deleted.  */
+	  while ((GET_CODE (insn) == INSN || GET_CODE (insn) == NOTE)
+		 && !can_throw_internal (insn)
+		 && insn != bb->head)
 	    insn = PREV_INSN (insn);
 	  if (GET_CODE (insn) != CALL_INSN && !can_throw_internal (insn))
 	    abort ();

gcc/toplev.c

@@ -3267,6 +3267,10 @@ rest_of_compilation (decl)
       rebuild_jump_labels_after_combine
 	= combine_instructions (insns, max_reg_num ());
 
+      /* Always purge dead edges, as we may eliminate an insn throwing
+         exception.  */
+      rebuild_jump_labels_after_combine |= purge_all_dead_edges ();
+
       /* Combining insns may have turned an indirect jump into a
 	 direct jump.  Rebuid the JUMP_LABEL fields of jumping
 	 instructions.  */
@@ -3277,7 +3281,6 @@ rest_of_compilation (decl)
 	  timevar_pop (TV_JUMP);
 
 	  timevar_push (TV_FLOW);
-	  purge_all_dead_edges ();
 	  cleanup_cfg (CLEANUP_EXPENSIVE);
 
 	  /* Blimey.  We've got to have the CFG up to date for the call to