From ed14c914b7a42bdb6ed6a455096993b8d51d716a Mon Sep 17 00:00:00 2001
From: prathamesh3492 <prathamesh3492@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Wed, 27 Sep 2017 00:03:07 +0000
Subject: [PATCH] 2017-09-26  Prathamesh Kulkarni 
 <prathamesh.kulkarni@linaro.org>

	* match.pd ((X / Y) == 0 -> X < Y): New pattern.
	((X / Y) != 0 -> X >= Y): Likewise.

testsuite/
	* gcc.dg/tree-ssa/cmpdiv.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@253218 138bc75d-0d04-0410-961f-82ee72b054a4
---
 gcc/ChangeLog                          |  5 +++++
 gcc/match.pd                           | 12 ++++++++++++
 gcc/testsuite/ChangeLog                |  4 ++++
 gcc/testsuite/gcc.dg/tree-ssa/cmpdiv.c | 18 ++++++++++++++++++
 4 files changed, 39 insertions(+)
 create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/cmpdiv.c

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 40e179bf79e..ad090d2161c 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2017-09-26  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>
+
+	* match.pd ((X / Y) == 0 -> X < Y): New pattern.
+	((X / Y) != 0 -> X >= Y): Likewise.
+
 2017-09-26  Carl Love  <cel@us.ibm.com>
 
 	* config/rs6000/rs6000-c.c (P9V_BUILTIN_VEC_XL_LEN_R,
diff --git a/gcc/match.pd b/gcc/match.pd
index 0863273b244..43ab226a705 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1275,6 +1275,18 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
 	   || TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0))))
    (op @1 @0))))
 
+/* Transform:
+ * (X / Y) == 0 -> X < Y if X, Y are unsigned.
+ * (X / Y) != 0 -> X >= Y, if X, Y are unsigned.
+ */
+(for cmp (eq ne)
+     ocmp (lt ge)
+ (simplify
+  (cmp (trunc_div @0 @1) integer_zerop)
+  (if (TYPE_UNSIGNED (TREE_TYPE (@0))
+       && (VECTOR_TYPE_P (type) || !VECTOR_TYPE_P (TREE_TYPE (@0))))
+   (ocmp @0 @1))))
+
 /* X == C - X can never be true if C is odd.  */
 (for cmp (eq ne)
  (simplify
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 64aea85c664..c064775317b 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2017-09-26  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>
+
+	* gcc.dg/tree-ssa/cmpdiv.c: New test.
+
 2017-09-26  Carl Love  <cel@us.ibm.com>
 
 	* gcc.target/powerpc/builtins-5-p9-runnable.c: Add new runable test
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/cmpdiv.c b/gcc/testsuite/gcc.dg/tree-ssa/cmpdiv.c
new file mode 100644
index 00000000000..14161f5ea6f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/cmpdiv.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized-raw" } */
+
+_Bool f1(unsigned x, unsigned y)
+{
+  unsigned t1 = x / y;
+  _Bool t2 = (t1 != 0);
+  return t2;
+}
+
+_Bool f2(unsigned x, unsigned y)
+{
+  unsigned t1 = x / y;
+  _Bool t2 = (t1 == 0);
+  return t2;
+}
+
+/* { dg-final { scan-tree-dump-not "trunc_div_expr" "optimized" } } */
-- 
2.11.4.GIT