--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.replacements.amd64/src/org/graalvm/compiler/replacements/amd64/AMD64LongSubstitutions.java	Thu Oct 31 16:54:16 2019 -0700
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2019, 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.
+ */
+
+
+package org.graalvm.compiler.replacements.amd64;
+
+// JaCoCo Exclude
+
+import static org.graalvm.compiler.replacements.NodeIntrinsificationProvider.INJECTED_TARGET;
+
+import org.graalvm.compiler.api.replacements.ClassSubstitution;
+import org.graalvm.compiler.api.replacements.Fold;
+import org.graalvm.compiler.api.replacements.MethodSubstitution;
+import org.graalvm.compiler.core.common.SuppressFBWarnings;
+import org.graalvm.compiler.replacements.nodes.BitScanForwardNode;
+import org.graalvm.compiler.replacements.nodes.BitScanReverseNode;
+
+import jdk.vm.ci.amd64.AMD64;
+import jdk.vm.ci.code.TargetDescription;
+
+@ClassSubstitution(Long.class)
+public class AMD64LongSubstitutions {
+
+    @Fold
+    static boolean lzcnt(@Fold.InjectedParameter TargetDescription target) {
+        AMD64 arch = (AMD64) target.arch;
+        return arch.getFeatures().contains(AMD64.CPUFeature.LZCNT) && arch.getFlags().contains(AMD64.Flag.UseCountLeadingZerosInstruction);
+    }
+
+    @Fold
+    static boolean tzcnt(@Fold.InjectedParameter TargetDescription target) {
+        AMD64 arch = (AMD64) target.arch;
+        return arch.getFeatures().contains(AMD64.CPUFeature.BMI1) && arch.getFlags().contains(AMD64.Flag.UseCountTrailingZerosInstruction);
+    }
+
+    @MethodSubstitution
+    @SuppressFBWarnings(value = "NP_NULL_PARAM_DEREF_NONVIRTUAL", justification = "foldable method parameters are injected")
+    public static int numberOfLeadingZeros(long i) {
+        if (lzcnt(INJECTED_TARGET)) {
+            return AMD64CountLeadingZerosNode.countLeadingZeros(i);
+        }
+        if (i == 0) {
+            return 64;
+        }
+        return 63 - BitScanReverseNode.unsafeScan(i);
+    }
+
+    @MethodSubstitution
+    @SuppressFBWarnings(value = "NP_NULL_PARAM_DEREF_NONVIRTUAL", justification = "foldable method parameters are injected")
+    public static int numberOfTrailingZeros(long i) {
+        if (tzcnt(INJECTED_TARGET)) {
+            return AMD64CountTrailingZerosNode.countTrailingZeros(i);
+        }
+
+        if (i == 0) {
+            return 64;
+        }
+        return BitScanForwardNode.unsafeScan(i);
+    }
+}