tree-tailcall.c (tree_optimize_tail_calls_1): Use fold_convert, reverting my…

tree-tailcall.c (tree_optimize_tail_calls_1): Use fold_convert, reverting my 2004-09-07 patch to use build_int_cst.

.:	* tree-tailcall.c (tree_optimize_tail_calls_1): Use fold_convert,
	reverting my 2004-09-07 patch to use build_int_cst.
testsuite:
	* gcc.c-torture/compile/acc1.c: New.

From-SVN: r88759

gcc/ChangeLog

+2004-10-08  Nathan Sidwell  <nathan@codesourcery.com>
+
+	* tree-tailcall.c (tree_optimize_tail_calls_1): Use fold_convert,
+	reverting my 2004-09-07 patch to use build_int_cst.
+
 2004-10-08  Eric Botcazou  <ebotcazou@libertysurf.fr>
 
 	PR target/17245

gcc/testsuite/ChangeLog

+2004-10-08  Nathan Sidwell  <nathan@codesourcery.com>
+
+	* gcc.c-torture/compile/acc1.c: New.
+
 2004-10-08  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	* gcc.dg/darwin-longdouble.c: Include stdlib.h and string.h.
@@ -22329,7 +22333,7 @@ Thu Apr 27 15:58:18 MET DST 2000  Jan Hubicka  <jh@suse.cz>
 
 	* gcc.c-torture/compile/labels-2.c: New test.
 
-1999-12-27  Martin von Löwis  <loewis@informatik.hu-berlin.de>
+1999-12-27  Martin von Lwis  <loewis@informatik.hu-berlin.de>
 
 	* gcc.c-torture/execute/991227-1.c: New test.
 
@@ -22337,7 +22341,7 @@ Thu Apr 27 15:58:18 MET DST 2000  Jan Hubicka  <jh@suse.cz>
 
 	* g++.old-deja/g++.pt/instantiate6.C: Remove excess errors XFAIL.
 
-1999-12-21  Martin von Löwis  <loewis@informatik.hu-berlin.de>
+1999-12-21  Martin von Lwis  <loewis@informatik.hu-berlin.de>
 
 	* gcc.c-torture/execute/991221-1.c: New test.
 

gcc/testsuite/gcc.c-torture/compile/acc1.c

+/* { dg-options "-O2 -ffast-math" } */
+
+/* Fast maths allows tail recursion to be turned into iteration.  */
+
+double
+foo (int n, double f)
+{
+  if (n == 0)
+    return f;
+  else
+    return f + foo (n - 1, f);
+}
+
+double
+bar (int n, double f)
+{
+  if (n == 0)
+    return f;
+  else
+    return f * bar (n - 1, f);
+}

gcc/tree-tailcall.c

@@ -896,7 +896,11 @@ tree_optimize_tail_calls_1 (bool opt_tailcalls)
 	  add_referenced_tmp_var (tmp);
 
 	  phi = create_phi_node (tmp, first);
-	  add_phi_arg (&phi, build_int_cst (ret_type, 0), EDGE_PRED (first, 0));
+	  add_phi_arg (&phi,
+		       /* RET_TYPE can be a float when -ffast-maths is
+			  enabled.  */
+		       fold_convert (ret_type, integer_zero_node),
+		       EDGE_PRED (first, 0));
 	  a_acc = PHI_RESULT (phi);
 	}
 
@@ -908,7 +912,11 @@ tree_optimize_tail_calls_1 (bool opt_tailcalls)
 	  add_referenced_tmp_var (tmp);
 
 	  phi = create_phi_node (tmp, first);
-	  add_phi_arg (&phi, build_int_cst (ret_type, 1), EDGE_PRED (first, 0));
+	  add_phi_arg (&phi,
+		       /* RET_TYPE can be a float when -ffast-maths is
+			  enabled.  */
+		       fold_convert (ret_type, integer_one_node),
+		       EDGE_PRED (first, 0));
 	  m_acc = PHI_RESULT (phi);
 	}
     }