./: * libgcc2.c (__throw): Use __builtin_return_addr instead of __eh_pc.

	* except.c: Lose outer_context_label_stack.
 	(expand_eh_region_end): Rethrow from outer_context here.
	(expand_fixup_region_end): Let expand_eh_region_end do the rethrow.
	(expand_internal_throw): Take no args.
	(expand_internal_throw_indirect): Lose.
	(expand_leftover_cleanups, expand_start_all_catch): Use expand_rethrow.
	(expand_start_all_catch): Start a rethrow region.
	(expand_end_all_catch): End it.
	(expand_rethrow): New fn.
	* except.h: Reflect above changes.

cp/:	* except.c (expand_end_catch_block): Lose rethrow region.
	(expand_start_catch_block): Likewise.
	(expand_end_catch_block): Don't expand_leftover_cleanups.

From-SVN: r16937

gcc/ChangeLog

+Wed Dec  3 12:01:56 1997  Jason Merrill  <jason@yorick.cygnus.com>
+
+	* libgcc2.c (__throw): Use __builtin_return_addr instead of __eh_pc.
+	* except.c: Lose outer_context_label_stack.
+ 	(expand_eh_region_end): Rethrow from outer_context here.
+	(expand_fixup_region_end): Let expand_eh_region_end do the rethrow.
+	(expand_internal_throw): Take no args.
+	(expand_internal_throw_indirect): Lose.
+	(expand_leftover_cleanups, expand_start_all_catch): Use expand_rethrow.
+	(expand_start_all_catch): Start a rethrow region.
+	(expand_end_all_catch): End it.
+	(expand_rethrow): New fn.
+	* except.h: Reflect above changes.
+	* flow.c: Revert change of Nov 27.
+
 Thu Dec  4 00:24:09 1997  Jeffrey A Law  (law@cygnus.com)
 
 	* i386/t-sol2 (CRTSTUFF_T_CFLAGS): Turn on the optimizer.

gcc/Makefile.in

@@ -280,7 +280,7 @@ LIBGCC2 = libgcc2.a
 #
 # -fexceptions is necessary for eh.o now that the exceptions are
 # the default for g++ only.
-LIBGCC2_DEBUG_CFLAGS = -g1
+LIBGCC2_DEBUG_CFLAGS = -g
 LIBGCC2_CFLAGS = -O2 $(LIBGCC2_INCLUDES) $(GCC_CFLAGS) $(TARGET_LIBGCC2_CFLAGS) $(LIBGCC2_DEBUG_CFLAGS) -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED -fexceptions @inhibit_libc@ 
 
 # Additional options to use when compiling libgcc2.a.

gcc/cp/ChangeLog

+Wed Dec  3 20:02:39 1997  Jason Merrill  <jason@yorick.cygnus.com>
+
+	* except.c (expand_end_catch_block): Lose rethrow region.
+	(expand_start_catch_block): Likewise.
+	(expand_end_catch_block): Don't expand_leftover_cleanups.
+
 Wed Dec  3 13:24:04 1997  Benjamin Kosnik  <bkoz@rhino.cygnus.com>
 
 	* pt.c (tsubst): Remove tree_cons call (places redundant info into

gcc/cp/except.c

@@ -185,10 +185,13 @@ static tree Unwind;
 
    ========================================================================= */
 
+#ifndef DWARF2_UNWIND_INFO
 /* Holds the pc for doing "throw" */
 static tree saved_pc;
 
 extern int throw_used;
+#endif
+
 extern rtx catch_clauses;
 extern tree const_ptr_type_node;
 
@@ -255,12 +258,14 @@ init_exception_processing ()
 
   pop_lang_context ();
 
+#ifndef DWARF2_UNWIND_INFO
   d = build_decl (VAR_DECL, get_identifier ("__eh_pc"), ptr_type_node);
   TREE_PUBLIC (d) = 1;
   DECL_EXTERNAL (d) = 1;
   DECL_ARTIFICIAL (d) = 1;
   cp_finish_decl (d, NULL_TREE, NULL_TREE, 0, 0);
   saved_pc = d;
+#endif
 
   /* If we use setjmp/longjmp EH, arrange for all cleanup actions to
      be protected with __terminate.  */
@@ -520,17 +525,6 @@ expand_start_catch_block (declspecs, declarator)
   if (! doing_eh (1))
     return;
 
-  /* If we are not doing setjmp/longjmp EH, because we are reordered
-     out of line, we arrange to rethrow in the outer context so as to
-     skip through the terminate region we are nested in, should we
-     encounter an exception in the catch handler.  We also need to do
-     this because we are not physically within the try block, if any,
-     that contains this catch block.
-
-     Matches the end in expand_end_catch_block.  */
-  if (! exceptions_via_longjmp)
-    expand_eh_region_start ();
-
   /* Create a binding level for the eh_info and the exception object
      cleanup.  */
   pushlevel (0);
@@ -655,36 +649,11 @@ expand_end_catch_block ()
   expand_end_bindings (getdecls (), kept_level_p (), 0);
   poplevel (kept_level_p (), 1, 0);
 
-  if (! exceptions_via_longjmp)
-    {
-      /* If we are not doing setjmp/longjmp EH, we need an extra
-	 region around the whole catch block to skip through the
-	 terminate region we are nested in.  */
-
-      tree t = make_node (RTL_EXPR);
-      TREE_TYPE (t) = void_type_node;
-      RTL_EXPR_RTL (t) = const0_rtx;
-      TREE_SIDE_EFFECTS (t) = 1;
-      do_pending_stack_adjust ();
-      start_sequence_for_rtl_expr (t);
-
-      expand_internal_throw (outer_context_label_stack->u.rlabel);
-
-      do_pending_stack_adjust ();
-      RTL_EXPR_SEQUENCE (t) = get_insns ();
-      end_sequence ();
-
-      /* For the rethrow region.  */
-      expand_eh_region_end (t);
-    }
-
   /* Fall to outside the try statement when done executing handler and
      we fall off end of handler.  This is jump Lresume in the
      documentation.  */
   expand_goto (top_label_entry (&caught_return_label_stack));
 
-  expand_leftover_cleanups ();
-
   /* label we emit to jump to if this catch block didn't match.  */
   /* This the closing } in the `if (eq) {' of the documentation.  */
   emit_label (pop_label_entry (&false_label_stack));
@@ -1318,18 +1287,7 @@ expand_throw (exp)
       expand_expr (exp, const0_rtx, VOIDmode, EXPAND_NORMAL);
     }
 
-  if (exceptions_via_longjmp)
-    emit_throw ();
-  else
-    {
-      /* This is the label that represents where in the code we were, when
-	 we got an exception.  This needs to be updated when we rethrow an
-	 exception, so that the matching routine knows to search out.  */
-      label = gen_label_rtx ();
-      emit_label (label);
-
-      expand_internal_throw (label);
-    }
+  expand_internal_throw ();
 }
 
 /* Build a throw expression.  */

gcc/except.h

@@ -192,10 +192,9 @@ extern void add_partial_entry			PROTO((tree handler));
 
 extern void end_protect_partials		PROTO((void));
 
-/* An internal throw with a direct CONTEXT we want to throw
-   from. CONTEXT must be a label.  */
+/* An internal throw.  */
 
-extern void expand_internal_throw		PROTO((rtx context));
+extern void expand_internal_throw		PROTO((void));
 
 /* Called from expand_exception_blocks and expand_end_catch_block to
    expand and pending handlers.  */
@@ -227,11 +226,6 @@ extern void check_exception_handler_labels	PROTO((void));
 
 extern struct label_node *caught_return_label_stack;
 
-/* Keeps track of the label used as the context of a throw to rethrow an
-   exception to the outer exception region.  */
-
-extern struct label_node *outer_context_label_stack;
-
 /* A random area used for purposes elsewhere.  */
 
 extern struct label_node *false_label_stack;

gcc/flow.c

@@ -472,15 +472,10 @@ find_basic_blocks (f, nonlocal_label_list)
       /* If we encounter a CALL_INSN, note which exception handler it
 	 might pass control to.
 
-	 Because we do rethrows by loading the address of a label into
-	 __eh_pc and throwing, we need to treat labels as potentially
-	 jumping to exception handlers.
-
 	 If doing asynchronous exceptions, record the active EH handler
 	 for every insn, since most insns can throw.  */
       else if (eh_note
 	       && (asynchronous_exceptions
-		   || code == CODE_LABEL
 		   || (GET_CODE (insn) == CALL_INSN
 		       && ! find_reg_note (insn, REG_RETVAL, NULL_RTX))))
 	active_eh_handler[INSN_UID (insn)] = XEXP (eh_note, 0);
@@ -574,11 +569,7 @@ find_basic_blocks (f, nonlocal_label_list)
 			   associated insns aren't marked dead, so we make
 			   the block in question live and create an edge from
 			   this insn to the label.  This is not strictly
-			   correct, but it is close enough for now.
-
-			   We also need to mark the CODE_LABEL as reaching
-			   its exception handler for nested exceptions to
-			   to work.  */
+			   correct, but it is close enough for now.  */
 			for (note = REG_NOTES (insn);
 			     note;
 			     note = XEXP (note, 1))
@@ -590,14 +581,6 @@ find_basic_blocks (f, nonlocal_label_list)
 				mark_label_ref (gen_rtx (LABEL_REF,
 							 VOIDmode, x),
 						insn, 0);
-
-				/* If the CODE_LABEL has an active exception
-				   handler, then make an edge to the exception
-				   handler from this insn.  */
-				if (active_eh_handler[INSN_UID (x)])
-				  mark_label_ref (gen_rtx (LABEL_REF, VOIDmode,
-							   active_eh_handler[INSN_UID (x)]),
-						  insn, 0);
 			      }
 			  }
 

gcc/libgcc2.c

@@ -3154,8 +3154,6 @@ __sjpopnthrow ()
 /* This value identifies the place from which an exception is being
    thrown.  */
 
-void *__eh_pc;
-
 #ifdef EH_TABLE_LOOKUP
 
 EH_TABLE_LOOKUP
@@ -3212,6 +3210,8 @@ find_exception_handler (void *pc, exception_table *table)
 /* Support code for exception handling using inline unwinders or
    __unwind_function.  */
 
+void *__eh_pc;
+
 #ifndef EH_TABLE_LOOKUP
 typedef struct exception_table_node {
   exception_table *table;
@@ -3489,7 +3489,7 @@ in_reg_window (int reg, frame_state *udata)
 void
 __throw ()
 {
-  void *pc, *handler, *retaddr;
+  void *pc, *handler, *retaddr, *__eh_pc;
   frame_state ustruct, ustruct2;
   frame_state *udata = &ustruct;
   frame_state *sub_udata = &ustruct2;
@@ -3524,6 +3524,7 @@ label:
   __builtin_unwind_init ();
 
   /* Now reset pc to the right throw point.  */
+  __eh_pc = __builtin_extract_return_addr (__builtin_return_address (0)) - 1;
   pc = __eh_pc;
 
   handler = 0;