Merge pull request #526 from JasonFengJ9/mergetmp

Merge master HEAD into openj9-staging

doc/hotspot-style.html

@@ -72,6 +72,7 @@ <h1 class="title">HotSpot Coding Style</h1>
 <li><a href="#expression-sfinae" id="toc-expression-sfinae">Expression
 SFINAE</a></li>
 <li><a href="#enum" id="toc-enum">enum</a></li>
+<li><a href="#alignas" id="toc-alignas">alignas</a></li>
 <li><a href="#thread_local" id="toc-thread_local">thread_local</a></li>
 <li><a href="#nullptr" id="toc-nullptr">nullptr</a></li>
 <li><a href="#atomic" id="toc-atomic">&lt;atomic&gt;</a></li>
@@ -598,7 +599,7 @@ <h3 id="c-standard-library">C++ Standard Library</h3>
 <code>std::numeric_limits</code>.</li>
 <li><code>#include &lt;type_traits&gt;</code>.</li>
 <li><code>#include &lt;cstddef&gt;</code> to use
-<code>std::nullptr_t</code>.</li>
+<code>std::nullptr_t</code> and <code>std::max_align_t</code>.</li>
 </ul>
 <p>TODO: Rather than directly #including (permitted) Standard Library
 headers, use a convention of #including wrapper headers (in some
@@ -670,6 +671,52 @@ <h3 id="enum">enum</h3>
 constant members. Compilers having such bugs are no longer supported.
 Except where an enum is semantically appropriate, new code should use
 integral constants.</p>
+<h3 id="alignas">alignas</h3>
+<p><em>Alignment-specifiers</em> (<code>alignas</code> <a
+href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2341.pdf">n2341</a>)
+are permitted, with restrictions.</p>
+<p><em>Alignment-specifiers</em> are permitted when the requested
+alignment is a <em>fundamental alignment</em> (not greater than
+<code>alignof(std::max_align_t)</code> <a
+href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf">C++14
+3.11/2</a>).</p>
+<p><em>Alignment-specifiers</em> with an <em>extended alignment</em>
+(greater than <code>alignof(std::max_align_t)</code> <a
+href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf">C++14
+3.11/3</a>) may only be used to align variables with static or automatic
+storage duration (<a
+href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf">C++14
+3.7.1, 3.7.3</a>). As a consequence, <em>over-aligned types</em> are
+forbidden; this may change if HotSpot updates to using C++17 or later <a
+href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html">p0035r4</a>.</p>
+<p>Large <em>extended alignments</em> should be avoided, particularly
+for stack allocated objects. What is a large value may depend on the
+platform and configuration. There may also be hard limits for some
+platforms.</p>
+<p>An <em>alignment-specifier</em> must always be applied to a
+definition (<a
+href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf">C++14
+10.6.2/6</a>). (C++ allows an <em>alignment-specifier</em> to optionally
+also be applied to a declaration, so long as the definition has
+equivalent alignment. There isn't any known benefit from duplicating the
+alignment in a non-definition declaration, so such duplication should be
+avoided in HotSpot code.)</p>
+<p>Enumerations are forbidden from having <em>alignment-specifiers</em>.
+Aligned enumerations were originally permitted but insufficiently
+specified, and were later (C++20) removed <a
+href="https://cplusplus.github.io/CWG/issues/2354.html">CWG 2354</a>.
+Permitting such usage in HotSpot now would just cause problems in the
+future.</p>
+<p><em>Alignment-specifiers</em> are forbidden in <code>typedef</code>
+and <em>alias-declarations</em>. This may work or may have worked in
+some versions of some compilers, but was later (C++14) explicitly
+disallowed <a
+href="https://cplusplus.github.io/CWG/issues/1437.html">CWG
+1437</a>.</p>
+<p>The HotSpot macro <code>ATTRIBUTE_ALIGNED</code> provides similar
+capabilities for platforms that define it. This macro predates the use
+by HotSpot of C++ versions providing <code>alignas</code>. New code
+should use <code>alignas</code>.</p>
 <h3 id="thread_local">thread_local</h3>
 <p>Avoid use of <code>thread_local</code> (<a
 href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2659.htm">n2659</a>);

doc/hotspot-style.md

@@ -573,7 +573,7 @@ There are a few exceptions to this rule.
 * `#include <new>` to use placement `new`, `std::nothrow`, and `std::nothrow_t`.
 * `#include <limits>` to use `std::numeric_limits`.
 * `#include <type_traits>`.
-* `#include <cstddef>` to use `std::nullptr_t`.
+* `#include <cstddef>` to use `std::nullptr_t` and `std::max_align_t`.
 
 TODO: Rather than directly \#including (permitted) Standard Library
 headers, use a convention of \#including wrapper headers (in some
@@ -651,6 +651,51 @@ constant members.  Compilers having such bugs are no longer supported.
 Except where an enum is semantically appropriate, new code should use
 integral constants.
 
+### alignas
+
+_Alignment-specifiers_ (`alignas`
+[n2341](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2341.pdf))
+are permitted, with restrictions.
+
+_Alignment-specifiers_ are permitted when the requested alignment is a
+_fundamental alignment_ (not greater than `alignof(std::max_align_t)`
+[C++14 3.11/2](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf)).
+
+_Alignment-specifiers_ with an _extended alignment_ (greater than
+`alignof(std::max_align_t)`
+[C++14 3.11/3](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf))
+may only be used to align variables with static or automatic storage duration
+([C++14 3.7.1, 3.7.3](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf)).
+As a consequence, _over-aligned types_ are forbidden; this may change if
+HotSpot updates to using C++17 or later
+[p0035r4](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html).
+
+Large _extended alignments_ should be avoided, particularly for stack
+allocated objects.  What is a large value may depend on the platform and
+configuration.  There may also be hard limits for some platforms.
+
+An _alignment-specifier_ must always be applied to a definition
+([C++14 10.6.2/6](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4296.pdf)).
+(C++ allows an _alignment-specifier_ to optionally also be applied to a
+declaration, so long as the definition has equivalent alignment. There isn't
+any known benefit from duplicating the alignment in a non-definition
+declaration, so such duplication should be avoided in HotSpot code.)
+
+Enumerations are forbidden from having _alignment-specifiers_. Aligned
+enumerations were originally permitted but insufficiently specified, and were
+later (C++20) removed
+[CWG 2354](https://cplusplus.github.io/CWG/issues/2354.html).
+Permitting such usage in HotSpot now would just cause problems in the future.
+
+_Alignment-specifiers_ are forbidden in `typedef` and _alias-declarations_.
+This may work or may have worked in some versions of some compilers, but was
+later (C++14) explicitly disallowed
+[CWG 1437](https://cplusplus.github.io/CWG/issues/1437.html).
+
+The HotSpot macro `ATTRIBUTE_ALIGNED` provides similar capabilities for
+platforms that define it. This macro predates the use by HotSpot of C++
+versions providing `alignas`. New code should use `alignas`.
+
 ### thread_local
 
 Avoid use of `thread_local`

src/java.base/share/classes/java/lang/invoke/LambdaForm.java

@@ -1089,7 +1089,7 @@ boolean contains(Name name) {
     static class NamedFunction {
         final MemberName member;
         private @Stable MethodHandle resolvedHandle;
-        @Stable MethodHandle invoker;
+        private @Stable MethodType type;
 
         NamedFunction(MethodHandle resolvedHandle) {
             this(resolvedHandle.internalMemberName(), resolvedHandle);
@@ -1185,10 +1185,6 @@ Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable {
             Object rval;
             try {
                 traceInterpreter("[ call", this, arguments);
-                if (invoker == null) {
-                    traceInterpreter("| getInvoker", this);
-                    invoker();
-                }
                 // resolvedHandle might be uninitialized, ok for tracing
                 if (resolvedHandle == null) {
                     traceInterpreter("| resolve", this);
@@ -1204,17 +1200,24 @@ Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable {
         }
 
         private MethodHandle invoker() {
-            if (invoker != null)  return invoker;
-            // Get an invoker and cache it.
-            return invoker = computeInvoker(methodType().form());
+            return computeInvoker(methodType().form());
         }
 
         MethodType methodType() {
-            if (resolvedHandle != null)
+            MethodType type = this.type;
+            if (type == null) {
+                this.type = type = calculateMethodType(member, resolvedHandle);
+            }
+            return type;
+        }
+
+        private static MethodType calculateMethodType(MemberName member, MethodHandle resolvedHandle) {
+            if (resolvedHandle != null) {
                 return resolvedHandle.type();
-            else
+            } else {
                 // only for certain internal LFs during bootstrapping
                 return member.getInvocationType();
+            }
         }
 
         MemberName member() {

src/java.base/share/classes/java/math/MutableBigInteger.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2022, 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
@@ -1531,13 +1531,10 @@ private MutableBigInteger divideMagnitude(MutableBigInteger div,
         quotient.intLen = limit;
         int[] q = quotient.value;
 
-
-        // Must insert leading 0 in rem if its length did not change
-        if (rem.intLen == nlen) {
-            rem.offset = 0;
-            rem.value[0] = 0;
-            rem.intLen++;
-        }
+        // Insert leading 0 in rem
+        rem.offset = 0;
+        rem.value[0] = 0;
+        rem.intLen++;
 
         int dh = divisor[0];
         long dhLong = dh & LONG_MASK;

src/java.base/share/classes/sun/net/www/protocol/http/HttpURLConnection.java

@@ -1999,8 +1999,8 @@ private InputStream getInputStream0() throws IOException {
                 return inputStream;
             } while (redirects < maxRedirects);
 
-            throw new ProtocolException("Server redirected too many " +
-                                        " times ("+ redirects + ")");
+            throw new ProtocolException("Server redirected too many times (" +
+                    redirects + ")");
         } catch (RuntimeException e) {
             disconnectInternal();
             rememberedException = e;

src/java.desktop/macosx/native/libawt_lwawt/awt/CClipboard.m

@@ -136,15 +136,16 @@ - (BOOL) checkPasteboardWithoutNotification:(id)application {
     jint nElements = (*env)->GetArrayLength(env, inTypes);
     NSMutableArray *formatArray = [NSMutableArray arrayWithCapacity:nElements];
     jlong *elements = (*env)->GetPrimitiveArrayCritical(env, inTypes, NULL);
+    if (elements != NULL) {
+        for (i = 0; i < nElements; i++) {
+            NSString *pbFormat = formatForIndex(elements[i]);
+            if (pbFormat)
+                [formatArray addObject:pbFormat];
+        }
 
-    for (i = 0; i < nElements; i++) {
-        NSString *pbFormat = formatForIndex(elements[i]);
-        if (pbFormat)
-            [formatArray addObject:pbFormat];
+        (*env)->ReleasePrimitiveArrayCritical(env, inTypes, elements, JNI_ABORT);
+        [[CClipboard sharedClipboard] declareTypes:formatArray withOwner:inJavaClip jniEnv:env];
     }
-
-    (*env)->ReleasePrimitiveArrayCritical(env, inTypes, elements, JNI_ABORT);
-    [[CClipboard sharedClipboard] declareTypes:formatArray withOwner:inJavaClip jniEnv:env];
 JNI_COCOA_EXIT(env);
 }
 

src/java.desktop/macosx/native/libawt_lwawt/font/CCharToGlyphMapper.m

@@ -58,12 +58,14 @@
 {
     jint *glyphCodeInts = (*env)->GetPrimitiveArrayCritical(env, glyphs, 0);
 
-    CTS_GetGlyphsAsIntsForCharacters(awtFont, unicodes,
-                                     cgGlyphs, glyphCodeInts, count);
+    if (glyphCodeInts != NULL) {
+        CTS_GetGlyphsAsIntsForCharacters(awtFont, unicodes,
+                                         cgGlyphs, glyphCodeInts, count);
 
-    // Do not use JNI_COMMIT, as that will not free the buffer copy
-    // when +ProtectJavaHeap is on.
-    (*env)->ReleasePrimitiveArrayCritical(env, glyphs, glyphCodeInts, 0);
+        // Do not use JNI_COMMIT, as that will not free the buffer copy
+        // when +ProtectJavaHeap is on.
+        (*env)->ReleasePrimitiveArrayCritical(env, glyphs, glyphCodeInts, 0);
+    }
 }
 
 static inline void

src/java.desktop/macosx/native/libosxui/JRSUIController.m

@@ -277,11 +277,13 @@ static inline jint doPaintCGContext(CGContextRef cgRef, jlong controlPtr, jlong
     CGRect partBounds = JRSUIControlGetScrollBarPartBounds(control, frame, part);
 
     jdouble *rect = (*env)->GetPrimitiveArrayCritical(env, rectArray, NULL);
-    rect[0] = partBounds.origin.x;
-    rect[1] = partBounds.origin.y;
-    rect[2] = partBounds.size.width;
-    rect[3] = partBounds.size.height;
-    (*env)->ReleasePrimitiveArrayCritical(env, rectArray, rect, 0);
+    if (rect != NULL) {
+        rect[0] = partBounds.origin.x;
+        rect[1] = partBounds.origin.y;
+        rect[2] = partBounds.size.width;
+        rect[3] = partBounds.size.height;
+        (*env)->ReleasePrimitiveArrayCritical(env, rectArray, rect, 0);
+    }
 }
 
 /*

src/java.desktop/share/classes/java/awt/image/DataBuffer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2022, 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
@@ -35,13 +35,13 @@
 
 package java.awt.image;
 
-import sun.java2d.StateTrackable.State;
-import static sun.java2d.StateTrackable.State.*;
-import sun.java2d.StateTrackableDelegate;
+import java.lang.annotation.Native;
 
 import sun.awt.image.SunWritableRaster;
+import sun.java2d.StateTrackable.State;
+import sun.java2d.StateTrackableDelegate;
 
-import java.lang.annotation.Native;
+import static sun.java2d.StateTrackable.State.UNTRACKABLE;
 
 /**
  * This class exists to wrap one or more data arrays.  Each data array in
@@ -75,16 +75,16 @@ public abstract class DataBuffer {
     /** Tag for unsigned short data. */
     @Native public static final int TYPE_USHORT = 1;
 
-    /** Tag for signed short data.  Placeholder for future use. */
+    /** Tag for signed short data. */
     @Native public static final int TYPE_SHORT = 2;
 
     /** Tag for int data. */
     @Native public static final int TYPE_INT   = 3;
 
-    /** Tag for float data.  Placeholder for future use. */
+    /** Tag for float data. */
     @Native public static final int TYPE_FLOAT  = 4;
 
-    /** Tag for double data.  Placeholder for future use. */
+    /** Tag for double data. */
     @Native public static final int TYPE_DOUBLE  = 5;
 
     /** Tag for undefined data. */

src/java.desktop/share/classes/javax/swing/JPasswordField.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2022, 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
@@ -36,8 +36,10 @@
 import javax.accessibility.AccessibleRole;
 import javax.accessibility.AccessibleText;
 import javax.accessibility.AccessibleTextSequence;
+import javax.swing.text.AbstractDocument;
 import javax.swing.text.BadLocationException;
 import javax.swing.text.Document;
+import javax.swing.text.DocumentFilter;
 import javax.swing.text.Segment;
 
 /**
@@ -300,21 +302,27 @@ public String getText(int offs, int len) throws BadLocationException {
     public void setText(String t) {
         // overwrite the old data first
         Document doc = getDocument();
-        int nleft = doc.getLength();
-        Segment text = new Segment();
-        // we would like to get direct data array access, not a copy of it
-        text.setPartialReturn(true);
-        int offs = 0;
-        try {
-            while (nleft > 0) {
-                doc.getText(offs, nleft, text);
-                Arrays.fill(text.array, text.offset,
-                            text.count + text.offset, '\u0000');
-                nleft -= text.count;
-                offs += text.count;
+        DocumentFilter filter = null;
+        if (doc instanceof AbstractDocument adoc) {
+            filter = adoc.getDocumentFilter();
+        }
+        if (filter == null) {
+            int nleft = doc.getLength();
+            Segment text = new Segment();
+            // we would like to get direct data array access, not a copy of it
+            text.setPartialReturn(true);
+            int offs = 0;
+            try {
+                while (nleft > 0) {
+                    doc.getText(offs, nleft, text);
+                    Arrays.fill(text.array, text.offset,
+                                text.count + text.offset, '\u0000');
+                    nleft -= text.count;
+                    offs += text.count;
+                }
+            } catch (BadLocationException ignored) {
+                // we tried
             }
-        } catch (BadLocationException ignored) {
-            // we tried
         }
         super.setText(t);
     }