Fix String.compareTo AVX512 intrinsic typos.

compiler/src/org.graalvm.compiler.lir.amd64/src/org/graalvm/compiler/lir/amd64/AMD64ArrayCompareToOp.java

@@ -155,7 +155,7 @@ public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) {
         AMD64Address.Scale scale2 = null;
 
         // if (ae != StrIntrinsicNode::LL) {
-        if (kind1 == JavaKind.Byte && kind2 == JavaKind.Byte) {
+        if (!(kind1 == JavaKind.Byte && kind2 == JavaKind.Byte)) {
             stride2x2 = 0x20;
         }
 
@@ -531,7 +531,7 @@ public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) {
             masm.notq(cnt1);
             masm.bsfq(cnt2, cnt1);
             // if (ae != StrIntrinsicNode::LL) {
-            if (kind1 != JavaKind.Byte && kind2 != JavaKind.Byte) {
+            if (!(kind1 == JavaKind.Byte && kind2 == JavaKind.Byte)) {
                 // Divide diff by 2 to get number of chars
                 masm.sarl(cnt2, 1);
             }

compiler/src/org.graalvm.compiler.replacements.test/src/org/graalvm/compiler/replacements/test/StringCompareToAVX512Test.java

@@ -0,0 +1,61 @@
+/*
+ * 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.test;
+
+import org.graalvm.compiler.core.test.GraalCompilerTest;
+import org.junit.Test;
+
+// JDK-8228903
+public final class StringCompareToAVX512Test extends GraalCompilerTest {
+
+    public static int compareTo(String str1, String str2) {
+        return str1.compareTo(str2);
+    }
+
+    @Test
+    public void testLatin1VsUtf16_2() {
+        String latin1 = "000000001111111122222222333333334444444455555555666666667777777\u0099888888889";
+        String utf16 = "000000001111111122222222333333334444444455555555666666667777777\u0699888888889";
+        test("compareTo", latin1, utf16);
+        test("compareTo", utf16, latin1);
+    }
+
+    @Test
+    public void testLatin1VsUtf16_3() {
+        String latin1 = "00000000111111112222222233333333444444445555555566666666777777778888888\u008799999999AAAAAAAAB";
+        String utf16 = "00000000111111112222222233333333444444445555555566666666777777778888888\u058799999999AAAAAAAAB";
+        test("compareTo", latin1, utf16);
+        test("compareTo", utf16, latin1);
+    }
+
+    @Test
+    public void testLatin1VsUtf16() {
+        // java.lang.AssertionError: expected:<-1536> but was:<0>
+        String latin1 = "00000000111111112222222233333333\u0099444444455555555";
+        String utf16 = "00000000111111112222222233333333\u0699xxxxxxxxxxxxxxx";
+        test("compareTo", latin1, utf16);
+        test("compareTo", utf16, latin1);
+    }
+}