2005-11-26 Andrew Pinski <pinskia@physics.uc.edu>

        PR middle-end/23669
        * fold-const.c (fold_binary): Convert -A/-B to A/B for signed types
        when overflow is undefined.
2005-11-26  Andrew Pinski  <pinskia@physics.uc.edu>

        PR middle-end/23669
        * gcc.dg/tree-ssa/divide-1.c: New test.
        * gcc.dg/tree-ssa/divide-2.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@107543 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f9b467d..cc7b153 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2005-11-26  Andrew Pinski  <pinskia@physics.uc.edu>
+
+       PR middle-end/23669
+       * fold-const.c (fold_binary): Convert -A/-B to A/B for signed types
+       when overflow is undefined.
+
 2005-11-26  Hans-Peter Nilsson  <hp@axis.com>
 
        * doc/md.texi (Insn Canonicalizations): Refer to the

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 59037d5..63f1294 100644 (file)
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -8440,6 +8440,19 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
          && TREE_INT_CST_HIGH (arg1) == -1)
        return fold_convert (type, negate_expr (arg0));
 
+      /* Convert -A / -B to A / B when the type is signed and overflow is
+        undefined.  */
+      if (!TYPE_UNSIGNED (type) && !flag_wrapv
+         && TREE_CODE (arg0) == NEGATE_EXPR
+         && negate_expr_p (arg1))
+       return fold_build2 (code, type, TREE_OPERAND (arg0, 0),
+                           negate_expr (arg1));
+      if (!TYPE_UNSIGNED (type) && !flag_wrapv
+         && TREE_CODE (arg1) == NEGATE_EXPR
+         && negate_expr_p (arg0))
+       return fold_build2 (code, type, negate_expr (arg0),
+                           TREE_OPERAND (arg1, 0));
+
       /* If arg0 is a multiple of arg1, then rewrite to the fastest div
         operation, EXACT_DIV_EXPR.
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 126a70d..2cbcd6d 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2005-11-26  Andrew Pinski  <pinskia@physics.uc.edu>
+
+       PR middle-end/23669
+       * gcc.dg/tree-ssa/divide-1.c: New test.
+       * gcc.dg/tree-ssa/divide-2.c: New test.
+
 2005-11-26  Janne Blomqvist  <jb@gcc.gnu.org>
 
        PR libgfortran/24945

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/divide-1.c b/gcc/testsuite/gcc.dg/tree-ssa/divide-1.c
new file mode 100644 (file)
index 0000000..90acd8b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/divide-1.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+int f(int a)
+{
+  return (-a)/10;
+}
+
+
+/* { dg-final { scan-tree-dump-times "-a / 10" 0 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "a / -10" 1 "optimized"} } */
+
+/* { dg-final { cleanup-tree-dump "optimized" } } */
+

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/divide-2.c b/gcc/testsuite/gcc.dg/tree-ssa/divide-2.c
new file mode 100644 (file)
index 0000000..5d719c0
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/divide-2.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+int f(int a)
+{
+  return 10/-a;
+}
+
+
+/* { dg-final { scan-tree-dump-times "10 / -a" 0 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "-10 / a" 1 "optimized"} } */
+
+/* { dg-final { cleanup-tree-dump "optimized" } } */
+