re PR tree-optimization/17671 (PHI-OPT is not smart enough)

2005-03-06  Andrew Pinski  <pinskia@physics.uc.edu>

	PR tree-opt/17671
	* tree-ssa-phiopt.c (tree_ssa_phiopt): Rewrite so we base the
	bbs on the COND_EXPR instead of the PHI_NODEs.
	(candidate_bb_for_phi_optimization): Remove.
	(replace_phi_with_stmt): Rename to ...
	(replace_phi_edge_with_variable): this and change so that we
	replace the phi argument instead of removing the PHI.
	(conditional_replacement): Change so we deal with PHI with more
	than two arguments.
	(value_replacement): Likewise.
	(abs_replacement): Likewise.

2005-03-06  Andrew Pinski  <pinskia@physics.uc.edu>

	PR tree-opt/17671
	* gcc.dg/tree-ssa/phi-opt-[1-4].c: New tests.

From-SVN: r96067

gcc/ChangeLog

+2005-03-06  Andrew Pinski  <pinskia@physics.uc.edu>
+	
+	PR tree-opt/17671
+	* tree-ssa-phiopt.c (tree_ssa_phiopt): Rewrite so we base the
+	bbs on the COND_EXPR instead of the PHI_NODEs.
+	(candidate_bb_for_phi_optimization): Remove.
+	(replace_phi_with_stmt): Rename to ...
+	(replace_phi_edge_with_variable): this and change so that we
+	replace the phi argument instead of removing the PHI.
+	(conditional_replacement): Change so we deal with PHI with more
+	than two arguments.
+	(value_replacement): Likewise.
+	(abs_replacement): Likewise.
+
 2005-03-07  Aldy Hernandez  <aldyh@redhat.com>
 
 	* config/rs6000/rs6000-protos.h: Rename output_e500_flip_eq_bit to

gcc/testsuite/ChangeLog

+2005-03-06  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR tree-opt/17671
+	* gcc.dg/tree-ssa/phi-opt-[1-4].c: New tests.
+
 2005-03-07  Mark Mitchell  <mark@codesourcery.com>
 
 	* g++.dg/warn/Wnvdtor.C: New test.

gcc/testsuite/gcc.dg/tree-ssa/phi-opt-1.c

+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+int f(int a, int b, int c)
+{
+  if (c == 0) goto temp;
+  if (a == 0)
+   return 0;
+temp:
+  if (a == b)
+   return a;
+ return a;
+}
+
+/* There should be no ifs as the PHI arguments, we did not
+   optimize this before because PHI-OPT did not look at 
+   PHIs which have more than two arguments.  */
+/* { dg-final { scan-tree-dump-times "if" 0 "optimized"} } */
+

gcc/testsuite/gcc.dg/tree-ssa/phi-opt-2.c

+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+_Bool f1(_Bool a, _Bool b)
+{
+  if (a)
+   {
+     if (b)
+      return 1;
+     else
+      return 0;
+   }
+  return 0;
+}
+
+
+/* There should be only one if, the outer one; the inner one
+   should have been changed to straight line code with the
+   value of b (except that we don't fold ! (b != 0) into b
+   which can be fixed in a different patch).  */
+/* { dg-final { scan-tree-dump-times "if" 1 "optimized"} } */

gcc/testsuite/gcc.dg/tree-ssa/phi-opt-3.c

+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+int f(int a, int b)
+{
+  if (a == 0)
+   return 0;
+  if (a != b)
+   return a;
+ return a;
+}
+
+/* There should be no ifs as the PHI arguments, we did not
+   optimize this before because PHI-OPT did not look at 
+   PHIs which have more than two arguments.  */
+/* { dg-final { scan-tree-dump-times "if" 0 "optimized"} } */
+

gcc/testsuite/gcc.dg/tree-ssa/phi-opt-4.c

+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+_Bool t();
+_Bool t1();
+
+_Bool f1()
+{
+  return t() && t1();
+}
+
+/* There should be only one if, the outer one; the inner one
+   should have been changed to straight line code with the
+   value of b (except that we don't fold ! (b != 0) into b
+   which means that we miss a sib calling opportunity).  */
+/* { dg-final { scan-tree-dump-times "if " 1 "optimized"} } */
+