re PR middle-end/25529 ((unsigned * 2)/2 is not changed into unsigned &0x7FFFFFFF)

PR middle-end/25529
2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>

gcc/testsuite/ChangeLog:
	* gcc.dg/pr25529.c: New test.

gcc/ChangeLog:
	* match.pd (trunc_div (mult @0 integer_pow2p@1) @1) : New simplifier.

From-SVN: r226136

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 211f82ba6f73807422b442933ca471e1bf246a43..aca1f829b76e88bc32b9bc050c748dbf60378cfe 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
+
+         PR middle-end/25529
+         * match.pd (trunc_div (mult @0 integer_pow2p@1) @1) : New simplifier.
+
 2015-07-23  Kugan Vivekanandarajah  <kuganv@linaro.org>
 
        * config/arm/arm.c (arm_emit_movpair): Add REG_EQUAL notes to

diff --git a/gcc/match.pd b/gcc/match.pd
index 9c181f6e1424f06ed16b89c7f86a65a24e9003d0..cc3089753aa2b860d3fce5204a0a694edc2b0c67 100644 (file)
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -29,7 +29,8 @@ along with GCC; see the file COPYING3.  If not see
    integer_each_onep integer_truep
    real_zerop real_onep real_minus_onep
    CONSTANT_CLASS_P
-   tree_expr_nonnegative_p)
+   tree_expr_nonnegative_p
+   integer_pow2p)
 
 /* Operator lists.  */
 (define_operator_list tcc_comparison
@@ -280,6 +281,14 @@ along with GCC; see the file COPYING3.  If not see
        && integer_pow2p (@2) && tree_int_cst_sgn (@2) > 0)
    (bit_and @0 (convert (minus @1 { build_int_cst (TREE_TYPE (@1), 1); }))))))
 
+/* Simplify (unsigned t * 2)/2 -> unsigned t & 0x7FFFFFFF.  */
+(simplify
+ (trunc_div (mult @0 integer_pow2p@1) @1)
+ (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
+  (bit_and @0 { wide_int_to_tree
+               (type, wi::mask (TYPE_PRECISION (type) - wi::exact_log2 (@1),
+                                false, TYPE_PRECISION (type))); })))
+
 /* X % Y is smaller than Y.  */
 (for cmp (lt ge)
  (simplify

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 81d09f6fffc25dd6176fadd08cd3b56dac8340c2..9adf8768165a7c695a14216f5a1ed5a03063776b 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-07-24  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
+
+       PR middle-end/25529
+       * gcc.dg/pr25529.c: New test.
+
 2015-07-23  Kugan Vivekanandarajah  <kuganv@linaro.org>
 
        * gcc.target/arm/reg_equal_test.c: New test.

diff --git a/gcc/testsuite/gcc.dg/pr25529.c b/gcc/testsuite/gcc.dg/pr25529.c
new file mode 100644 (file)
index 0000000..336d93b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr25529.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* { dg-require-effective-target int32 } */
+
+int
+f (unsigned t)
+{
+  return (t * 2) / 2;
+}
+
+/* { dg-final { scan-tree-dump "\& 2147483647" "optimized" } } */