8184271: Time related C1 intrinsics produce inconsistent results when floating around

Summary: C1 intrinsics for System.nanoTime(), System.currentTimeMillis() and JVM.counterTime() should be pinned.
Reviewed-by: kvn, vlivanov, iveresov

src/share/vm/c1/c1_Instruction.hpp

@@ -1568,7 +1568,7 @@ LEAF(Intrinsic, StateSplit)
     set_needs_null_check(has_receiver);
 
     // some intrinsics can't trap, so don't force them to be pinned
-    if (!can_trap()) {
+    if (!can_trap() && !vmIntrinsics::should_be_pinned(_id)) {
       unpin(PinStateSplitConstructor);
     }
   }

src/share/vm/classfile/vmSymbols.cpp

@@ -324,6 +324,20 @@ vmIntrinsics::ID vmIntrinsics::for_raw_conversion(BasicType src, BasicType dest)
   return vmIntrinsics::_none;
 }
 
+// Some intrinsics produce different results if they are not pinned
+bool vmIntrinsics::should_be_pinned(vmIntrinsics::ID id) {
+  assert(id != vmIntrinsics::_none, "must be a VM intrinsic");
+  switch(id) {
+#ifdef TRACE_HAVE_INTRINSICS
+  case vmIntrinsics::_counterTime:
+#endif
+  case vmIntrinsics::_currentTimeMillis:
+  case vmIntrinsics::_nanoTime:
+    return true;
+  default:
+    return false;
+  }
+}
 
 #define VM_INTRINSIC_INITIALIZE(id, klass, name, sig, flags) #id "\0"
 static const char* vm_intrinsic_name_bodies =

src/share/vm/classfile/vmSymbols.hpp

@@ -1301,6 +1301,8 @@ public:
 
   // Raw conversion:
   static ID for_raw_conversion(BasicType src, BasicType dest);
+
+  static bool should_be_pinned(vmIntrinsics::ID id);
 };
 
 #endif // SHARE_VM_CLASSFILE_VMSYMBOLS_HPP

test/compiler/c1/TestPinnedIntrinsics.java

+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8184271
+ * @summary Test correct scheduling of System.nanoTime and System.currentTimeMillis C1 intrinsics.
+ * @run main/othervm -XX:TieredStopAtLevel=1 -Xbatch
+ *                   -XX:CompileCommand=dontinline,compiler.c1.TestPinnedIntrinsics::checkNanoTime
+ *                   -XX:CompileCommand=dontinline,compiler.c1.TestPinnedIntrinsics::checkCurrentTimeMillis
+ *                   compiler.c1.TestPinnedIntrinsics
+ */
+
+package compiler.c1;
+
+public class TestPinnedIntrinsics {
+
+    private static void testNanoTime() {
+        long start = System.nanoTime();
+        long end = System.nanoTime();
+        checkNanoTime(end - start);
+    }
+
+    private static void checkNanoTime(long diff) {
+        if (diff < 0) {
+            throw new RuntimeException("testNanoTime failed with " + diff);
+        }
+    }
+
+    private static void testCurrentTimeMillis() {
+        long start = System.currentTimeMillis();
+        long end = System.currentTimeMillis();
+        checkCurrentTimeMillis(end - start);
+    }
+
+    private static void checkCurrentTimeMillis(long diff) {
+        if (diff < 0) {
+            throw new RuntimeException("testCurrentTimeMillis failed with " + diff);
+        }
+    }
+
+    public static void main(String[] args) {
+        for (int i = 0; i < 100_000; ++i) {
+            testNanoTime();
+            testCurrentTimeMillis();
+        }
+    }
+}