2006-10-24 Richard Guenther <rguenther@suse.de>

	* builtins.c (fold_builtin_floor): Fold floor (x) where
	x is nonnegative to trunc (x).
	(fold_builtin_int_roundingfn): Fold lfloor (x) where x is
	nonnegative to FIX_TRUNC_EXPR.

	* gcc.dg/builtins-57.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@117998 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1505a08..ac9dcf7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,12 @@
 2006-10-24  Richard Guenther  <rguenther@suse.de>
 
+       * builtins.c (fold_builtin_floor): Fold floor (x) where
+       x is nonnegative to trunc (x).
+       (fold_builtin_int_roundingfn): Fold lfloor (x) where x is
+       nonnegative to FIX_TRUNC_EXPR.
+
+2006-10-24  Richard Guenther  <rguenther@suse.de>
+
        PR tree-optimization/29567
        * tree-vrp.c (register_edge_assert_for_1): Fix wrong logic
        for TRUTH_NOT_EXPR.  Clarify comments.

diff --git a/gcc/builtins.c b/gcc/builtins.c
index c165e34..78fc11f 100644 (file)
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -7355,6 +7355,12 @@ fold_builtin_floor (tree fndecl, tree arglist)
        }
     }
 
+  /* Fold floor (x) where x is nonnegative to trunc (x).  */
+  if (tree_expr_nonnegative_p (arg))
+    return build_function_call_expr (mathfn_built_in (TREE_TYPE (arg),
+                                                     BUILT_IN_TRUNC),
+                                    arglist);
+
   return fold_trunc_transparent_mathfn (fndecl, arglist);
 }
 
@@ -7473,6 +7479,18 @@ fold_builtin_int_roundingfn (tree fndecl, tree arglist)
        }
     }
 
+  switch (DECL_FUNCTION_CODE (fndecl))
+    {
+    CASE_FLT_FN (BUILT_IN_LFLOOR):
+    CASE_FLT_FN (BUILT_IN_LLFLOOR):
+      /* Fold lfloor (x) where x is nonnegative to FIX_TRUNC (x).  */
+      if (tree_expr_nonnegative_p (arg))
+       return fold_build1 (FIX_TRUNC_EXPR, TREE_TYPE (TREE_TYPE (fndecl)),
+                           arg);
+      break;
+    default:;
+    }
+
   return fold_fixed_mathfn (fndecl, arglist);
 }
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9136286..98445d5 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,9 @@
 2006-10-24  Richard Guenther  <rguenther@suse.de>
 
+       * gcc.dg/builtins-57.c: New testcase.
+
+2006-10-24  Richard Guenther  <rguenther@suse.de>
+
        PR tree-optimization/29567
        * gfortran.fortran-torture/compile/vrp_1.f90: New testcase.
 

diff --git a/gcc/testsuite/gcc.dg/builtins-57.c b/gcc/testsuite/gcc.dg/builtins-57.c
new file mode 100644 (file)
index 0000000..87fbd44
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/builtins-57.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-gimple" } */
+
+double foo (double x)
+{
+  return __builtin_floor (__builtin_fabs (x));
+}
+
+long bar (double x)
+{
+  return __builtin_lfloor (__builtin_fabs (x));
+}
+
+/* { dg-final { scan-tree-dump-not "lfloor" "gimple" } } */
+/* { dg-final { scan-tree-dump "trunc" "gimple" } } */
+/* { dg-final { cleanup-tree-dump "gimple" } } */