[committed] Fix multiple_p for two non-poly_ints

[Richard Sandiford]

Fix a stupid inversion.  This function is very rarely used and was
mostly to help split patches up, which is why it didn't get picked
up during initial testing.  Sorry for the mistake.

Tested on aarch64-linux-gnu, x86_64-linux-gnu and powerpc64-linux-gnu.
Applied as obvious.

Richard


2017-12-20  Richard Sandiford  <richard.sandif...@linaro.org>

gcc/
        * poly-int.h (multiple_p): Fix handling of two non-poly_ints.

gcc/testsuite/
        * gcc.dg/plugin/poly-int-tests.h (test_nonpoly_multiple_p): New
        function.
        (test_nonpoly_type): Call it.

Index: gcc/poly-int.h
===================================================================
--- gcc/poly-int.h      2017-12-20 08:55:30.768462429 +0000
+++ gcc/poly-int.h      2017-12-20 08:55:55.911492315 +0000
@@ -2027,7 +2027,7 @@ constant_multiple_p (const poly_int_pod<
 inline typename if_nonpoly2<Ca, Cb, bool>::type
 multiple_p (Ca a, Cb b)
 {
-  return a % b != 0;
+  return a % b == 0;
 }
 
 /* Return true if A is a (polynomial) multiple of B.  */
Index: gcc/testsuite/gcc.dg/plugin/poly-int-tests.h
===================================================================
--- gcc/testsuite/gcc.dg/plugin/poly-int-tests.h        2017-12-14 
00:05:54.955021396 +0000
+++ gcc/testsuite/gcc.dg/plugin/poly-int-tests.h        2017-12-20 
08:55:55.912492276 +0000
@@ -4505,6 +4505,19 @@ test_uhwi ()
                                   wi::uhwi (210, 16)));
 }
 
+/* Test multiple_p for non-polynomial T.  */
+
+template<typename T>
+static void
+test_nonpoly_multiple_p ()
+{
+  ASSERT_TRUE (multiple_p (T (6), T (2)));
+  ASSERT_TRUE (multiple_p (T (6), T (3)));
+  ASSERT_FALSE (multiple_p (T (6), T (4)));
+  ASSERT_FALSE (multiple_p (T (7), T (4)));
+  ASSERT_TRUE (multiple_p (T (8), T (4)));
+}
+
 /* Test known_size_p for non-polynomial T.  */
 
 template<typename T>
@@ -4523,6 +4536,7 @@ test_nonpoly_known_size_p ()
 static void
 test_nonpoly_type ()
 {
+  test_nonpoly_multiple_p<T> ();
   test_nonpoly_known_size_p<T> ();
 }