tree-eh.c (lower_try_finally_dup_block): Clear location information on stack restore statements.

	* tree-eh.c (lower_try_finally_dup_block): Clear location information
	on stack restore statements.
	(decide_copy_try_finally): Do not consider a stack restore statement as
	coming from sources.

From-SVN: r227805

gcc/ChangeLog

+2015-09-15  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* tree-eh.c (lower_try_finally_dup_block): Clear location information
+	on stack restore statements.
+	(decide_copy_try_finally): Do not consider a stack restore statement as
+	coming from sources.
+
 2015-09-15  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/alpha/alpha.c (alpha_expand_block_clear): Use

gcc/testsuite/ChangeLog

+2015-09-15  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/array24.adb: New test.
+	* gnat.dg/blocklocs.adb: Delete.
+
 2015-09-15  Marek Polacek  <polacek@redhat.com>
 
 	PR c/67580

gcc/testsuite/gnat.dg/array24.adb

+-- { dg-do compile }
+-- { dg-options "-fdump-tree-optimized" }
+
+procedure Array24 (N : Natural) is
+  S : String (1 .. N);
+  pragma Volatile (S);
+begin
+  S := (others => '0');
+end;
+
+-- { dg-final { scan-tree-dump-not "builtin_unwind_resume" "optimized"  } }

gcc/testsuite/gnat.dg/blocklocs.adb

--- { dg-do compile { target *-*-linux* } }
--- { dg-options "-gdwarf-2" }
-
-procedure Blocklocs (Choice : Integer; N : in out Integer) is
-begin
-   if Choice > 0 then
-      declare -- line 7
-         S : String (1 .. N * 2);
-         pragma Volatile (S);
-      begin
-	 S := (others => 'B');
-      end;    -- line 12
-   else
-      declare -- line 14
-	 S : String (1 .. N );
-	 pragma Volatile (S);
-      begin
-	 S := (others => '1');
-      end;    -- line 19
-   end if;
-end;
-   
--- { dg-final { scan-assembler "loc 1 7" } }
--- { dg-final { scan-assembler "loc 1 12" } }
--- { dg-final { scan-assembler "loc 1 14" } }
--- { dg-final { scan-assembler "loc 1 19" } }

gcc/tree-eh.c

@@ -915,7 +915,12 @@ lower_try_finally_dup_block (gimple_seq seq, struct leh_state *outer_state,
   for (gsi = gsi_start (new_seq); !gsi_end_p (gsi); gsi_next (&gsi))
     {
       gimple stmt = gsi_stmt (gsi);
-      if (LOCATION_LOCUS (gimple_location (stmt)) == UNKNOWN_LOCATION)
+      /* We duplicate __builtin_stack_restore at -O0 in the hope of eliminating
+	 it on the EH paths.  When it is not eliminated, make it transparent in
+	 the debug info.  */
+      if (gimple_call_builtin_p (stmt, BUILT_IN_STACK_RESTORE))
+	gimple_set_location (stmt, UNKNOWN_LOCATION);
+      else if (LOCATION_LOCUS (gimple_location (stmt)) == UNKNOWN_LOCATION)
 	{
 	  tree block = gimple_block (stmt);
 	  gimple_set_location (stmt, loc);
@@ -1604,8 +1609,12 @@ decide_copy_try_finally (int ndests, bool may_throw, gimple_seq finally)
 
       for (gsi = gsi_start (finally); !gsi_end_p (gsi); gsi_next (&gsi))
 	{
+	  /* Duplicate __builtin_stack_restore in the hope of eliminating it
+	     on the EH paths and, consequently, useless cleanups.  */
 	  gimple stmt = gsi_stmt (gsi);
-	  if (!is_gimple_debug (stmt) && !gimple_clobber_p (stmt))
+	  if (!is_gimple_debug (stmt)
+	      && !gimple_clobber_p (stmt)
+	      && !gimple_call_builtin_p (stmt, BUILT_IN_STACK_RESTORE))
 	    return false;
 	}
       return true;