PR tree-optimization/81588

	* tree-ssa-reassoc.c (optimize_range_tests_var_bound): If
	ranges[i].in_p, invert comparison code ccode.  For >/>=,
	swap rhs1 and rhs2 and comparison code unconditionally,
	for </<= don't do that.  Don't swap rhs1/rhs2 again if
	ranges[i].in_p, instead invert comparison code ccode if
	opcode or oe->rank is BIT_IOR_EXPR.

	* gcc.dg/tree-ssa/pr81588.c: New test.
	* gcc.dg/pr81588.c: New test.
	* gcc.c-torture/execute/pr81588.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-7-branch@250761 138bc75d-0d04-0410-961f-82ee72b054a4

6 files changed, 126 insertions, 9 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d3d5d7241b6..d1403195e63 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+2017-08-01  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/81588
+	* tree-ssa-reassoc.c (optimize_range_tests_var_bound): If
+	ranges[i].in_p, invert comparison code ccode.  For >/>=,
+	swap rhs1 and rhs2 and comparison code unconditionally,
+	for </<= don't do that.  Don't swap rhs1/rhs2 again if
+	ranges[i].in_p, instead invert comparison code ccode if
+	opcode or oe->rank is BIT_IOR_EXPR.
+
 2017-07-31  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
 	Backport from mainline
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 0659b699920..ace54311caa 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2017-08-01  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/81588
+	* gcc.dg/tree-ssa/pr81588.c: New test.
+	* gcc.dg/pr81588.c: New test.
+	* gcc.c-torture/execute/pr81588.c: New test.
+
 2017-07-31  Jakub Jelinek  <jakub@redhat.com>
 
 	PR sanitizer/81604
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr81588.c b/gcc/testsuite/gcc.c-torture/execute/pr81588.c
new file mode 100644
index 00000000000..b8f84b3e18c
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr81588.c
@@ -0,0 +1,45 @@
+/* PR tree-optimization/81588 */
+
+__attribute__((noinline, noclone)) int
+bar (int x)
+{
+  __asm volatile ("" : : "g" (x) : "memory");
+}
+
+__attribute__((noinline, noclone)) int
+foo (unsigned x, long long y)
+{
+  if (y < 0)
+    return 0;
+  if (y < (long long) (4 * x))
+    {
+      bar (y);
+      return 1;
+    }
+  return 0;
+}     
+
+int
+main ()
+{
+  volatile unsigned x = 10;
+  volatile long long y = -10000;
+  if (foo (x, y) != 0)
+    __builtin_abort ();
+  y = -1;
+  if (foo (x, y) != 0)
+    __builtin_abort ();
+  y = 0;
+  if (foo (x, y) != 1)
+    __builtin_abort ();
+  y = 39;
+  if (foo (x, y) != 1)
+    __builtin_abort ();
+  y = 40;
+  if (foo (x, y) != 0)
+    __builtin_abort ();
+  y = 10000;
+  if (foo (x, y) != 0)
+    __builtin_abort ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/pr81588.c b/gcc/testsuite/gcc.dg/pr81588.c
new file mode 100644
index 00000000000..4e83607f2a8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr81588.c
@@ -0,0 +1,26 @@
+/* PR tree-optimization/81588 */
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+long long int a = 5011877430933453486LL, c = 1;
+unsigned short b = 24847;
+
+#include "tree-ssa/pr81588.c"
+
+int
+main ()
+{
+  foo ();
+  if (c != 0)
+    __builtin_abort ();
+  a = 24846;
+  c = 1;
+  foo ();
+  if (c != 1)
+    __builtin_abort ();
+  a = -5;
+  foo ();
+  if (c != 0)
+    __builtin_abort ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr81588.c b/gcc/testsuite/gcc.dg/tree-ssa/pr81588.c
new file mode 100644
index 00000000000..2709abd89a1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr81588.c
@@ -0,0 +1,15 @@
+/* PR tree-optimization/81588 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-reassoc1-details" } */
+ 	
+extern long long int a, c;
+extern unsigned short b;
+
+/* { dg-final { scan-tree-dump-times "Optimizing range test \[^\n\r]* and comparison" 1 "reassoc1" } } */
+
+__attribute__((noinline, noclone)) void
+foo (void)
+{
+  if ((b > a) != (1 + (a < 0)))
+    c = 0;
+}
diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c
index cca41d3209c..e57a343c532 100644
--- a/gcc/tree-ssa-reassoc.c
+++ b/gcc/tree-ssa-reassoc.c
@@ -2941,17 +2941,26 @@ optimize_range_tests_var_bound (enum tree_code opcode, int first, int length,
 	{
 	case GT_EXPR:
 	case GE_EXPR:
-	  if (!ranges[i].in_p)
-	    std::swap (rhs1, rhs2);
+	case LT_EXPR:
+	case LE_EXPR:
+	  break;
+	default:
+	  continue;
+	}
+      if (ranges[i].in_p)
+	ccode = invert_tree_comparison (ccode, false);
+      switch (ccode)
+	{
+	case GT_EXPR:
+	case GE_EXPR:
+	  std::swap (rhs1, rhs2);
 	  ccode = swap_tree_comparison (ccode);
 	  break;
 	case LT_EXPR:
 	case LE_EXPR:
-	  if (ranges[i].in_p)
-	    std::swap (rhs1, rhs2);
 	  break;
 	default:
-	  continue;
+	  gcc_unreachable ();
 	}
 
       int *idx = map->get (rhs1);
@@ -2998,8 +3007,14 @@ optimize_range_tests_var_bound (enum tree_code opcode, int first, int length,
 	  fprintf (dump_file, "\n");
 	}
 
-      if (ranges[i].in_p)
-	std::swap (rhs1, rhs2);
+      operand_entry *oe = (*ops)[ranges[i].idx];
+      ranges[i].in_p = 0;
+      if (opcode == BIT_IOR_EXPR
+	  || (opcode == ERROR_MARK && oe->rank == BIT_IOR_EXPR))
+	{
+	  ranges[i].in_p = 1;
+	  ccode = invert_tree_comparison (ccode, false);
+	}
 
       unsigned int uid = gimple_uid (stmt);
       gimple_stmt_iterator gsi = gsi_for_stmt (stmt);
@@ -3026,7 +3041,6 @@ optimize_range_tests_var_bound (enum tree_code opcode, int first, int length,
 	}
       else
 	{
-	  operand_entry *oe = (*ops)[ranges[i].idx];
 	  tree ctype = oe->op ? TREE_TYPE (oe->op) : boolean_type_node;
 	  if (!INTEGRAL_TYPE_P (ctype)
 	      || (TREE_CODE (ctype) != BOOLEAN_TYPE
@@ -3048,7 +3062,7 @@ optimize_range_tests_var_bound (enum tree_code opcode, int first, int length,
 	  ranges[i].high = ranges[i].low;
 	}
       ranges[i].strict_overflow_p = false;
-      operand_entry *oe = (*ops)[ranges[*idx].idx];
+      oe = (*ops)[ranges[*idx].idx];
       /* Now change all the other range test immediate uses, so that
 	 those tests will be optimized away.  */
       if (opcode == ERROR_MARK)