[GR-62672] Refactorings for the identity hashcode support.

substratevm/src/com.oracle.objectfile/src/com/oracle/objectfile/debugentry/DebugInfoBase.java

@@ -171,11 +171,11 @@ public abstract class DebugInfoBase {
     /**
      * Bit mask used for tagging oops.
      */
-    private int reservedBitsMask;
+    private int reservedHubBitsMask;
     /**
      * Number of low order bits used for tagging oops.
      */
-    private int numReservedBits;
+    private int numReservedHubBits;
     /**
      * Number of bytes used to store an oop reference.
      */
@@ -211,8 +211,8 @@ public abstract class DebugInfoBase {
     public DebugInfoBase(ByteOrder byteOrder) {
         this.byteOrder = byteOrder;
         this.useHeapBase = true;
-        this.reservedBitsMask = 0;
-        this.numReservedBits = 0;
+        this.reservedHubBitsMask = 0;
+        this.numReservedHubBits = 0;
         this.compressionShift = 0;
         this.referenceSize = 0;
         this.pointerSize = 0;
@@ -250,12 +250,12 @@ public void installDebugInfo(DebugInfoProvider debugInfoProvider) {
         /*
          * Save count of low order tag bits that may appear in references.
          */
-        reservedBitsMask = debugInfoProvider.reservedBitsMask();
+        reservedHubBitsMask = debugInfoProvider.reservedHubBitsMask();
 
         /* Mask must be contiguous from bit 0. */
-        assert ((reservedBitsMask + 1) & reservedBitsMask) == 0;
+        assert ((reservedHubBitsMask + 1) & reservedHubBitsMask) == 0;
 
-        numReservedBits = Integer.bitCount(reservedBitsMask);
+        numReservedHubBits = Integer.bitCount(reservedHubBitsMask);
 
         /* Save amount we need to shift references by when loading from an object field. */
         compressionShift = debugInfoProvider.compressionShift();
@@ -705,12 +705,12 @@ public boolean useHeapBase() {
         return useHeapBase;
     }
 
-    public int reservedBitsMask() {
-        return reservedBitsMask;
+    public int reservedHubBitsMask() {
+        return reservedHubBitsMask;
     }
 
-    public int numReservedBits() {
-        return numReservedBits;
+    public int numReservedHubBits() {
+        return numReservedHubBits;
     }
 
     public int compressionShift() {

substratevm/src/com.oracle.objectfile/src/com/oracle/objectfile/debuginfo/DebugInfoProvider.java

@@ -52,7 +52,7 @@ public interface DebugInfoProvider {
     /**
      * Mask selecting low order bits used for tagging oops.
      */
-    int reservedBitsMask();
+    int reservedHubBitsMask();
 
     /**
      * Number of bytes used to store an oop reference.

substratevm/src/com.oracle.objectfile/src/com/oracle/objectfile/elf/dwarf/DwarfInfoSectionImpl.java

@@ -2132,8 +2132,8 @@ public int writeCompressedOopConversionExpression(boolean isHub, byte[] buffer,
          */
 
         boolean useHeapBase = dwarfSections.useHeapBase();
-        int reservedBitsMask = dwarfSections.reservedBitsMask();
-        int numReservedBits = dwarfSections.numReservedBits();
+        int reservedHubBitsMask = dwarfSections.reservedHubBitsMask();
+        int numReservedHubBits = dwarfSections.numReservedHubBits();
         int compressionShift = dwarfSections.compressionShift();
         int numAlignmentBits = dwarfSections.numAlignmentBits();
 
@@ -2143,12 +2143,12 @@ public int writeCompressedOopConversionExpression(boolean isHub, byte[] buffer,
          * The required expression will be one of these paths:
          *
          * push object address ................................ (1 byte) ..... [offset] ............
-         * IF reservedBitsMask != 0 ................................................................
-         * . push reservedBitsMask ............................ (1 byte) ..... [offset, mask] ......
+         * IF reservedHubBitsMask != 0 .............................................................
+         * . push reservedHubBitsMask.......................... (1 byte) ..... [offset, mask] ......
          * . NOT .............................................. (1 byte) ..... [offset, ~mask] .....
          * . AND .............................................. (1 byte) ..... [offset] ............
-         * . IF numReservedBits == numAlignmentBits && compressionShift == 0 .......................
-         * ... push numReservedBits ........................... (1 byte) ..... [offset, right shift]
+         * . IF numReservedHubBits == numAlignmentBits && compressionShift == 0 ....................
+         * ... push numReservedHubBits ........................ (1 byte) ..... [offset, right shift]
          * ... LSHR ........................................... (1 byte) ..... [offset] ............
          * ... IF compressionShift != numAlignmentBits .............................................
          * ..... push numAlignmentBits - compressionShift ..... (1 byte) ..... [offset, left shift]
@@ -2176,13 +2176,13 @@ public int writeCompressedOopConversionExpression(boolean isHub, byte[] buffer,
         pos = writeULEB(0, buffer, pos);
         int exprStart = pos;
         pos = writeExprOpcode(DwarfExpressionOpcode.DW_OP_push_object_address, buffer, pos);
-        if (isHub && reservedBitsMask != 0) {
-            if (numReservedBits == numAlignmentBits && compressionShift == 0) {
-                pos = writeExprOpcodeLiteral(reservedBitsMask, buffer, pos);
+        if (isHub && reservedHubBitsMask != 0) {
+            if (numReservedHubBits == numAlignmentBits && compressionShift == 0) {
+                pos = writeExprOpcodeLiteral(reservedHubBitsMask, buffer, pos);
                 pos = writeExprOpcode(DwarfExpressionOpcode.DW_OP_not, buffer, pos);
                 pos = writeExprOpcode(DwarfExpressionOpcode.DW_OP_and, buffer, pos);
             } else {
-                pos = writeExprOpcodeLiteral(numReservedBits, buffer, pos);
+                pos = writeExprOpcodeLiteral(numReservedHubBits, buffer, pos);
                 pos = writeExprOpcode(DwarfExpressionOpcode.DW_OP_shr, buffer, pos);
                 if (compressionShift != numAlignmentBits) {
                     pos = writeExprOpcodeLiteral(numAlignmentBits - compressionShift, buffer, pos);

substratevm/src/com.oracle.svm.core.genscavenge/src/com/oracle/svm/core/genscavenge/CompactingOldGeneration.java

@@ -48,6 +48,7 @@
 import com.oracle.svm.core.genscavenge.remset.BrickTable;
 import com.oracle.svm.core.genscavenge.remset.RememberedSet;
 import com.oracle.svm.core.graal.RuntimeCompilation;
+import com.oracle.svm.core.heap.Heap;
 import com.oracle.svm.core.heap.ObjectHeader;
 import com.oracle.svm.core.heap.ObjectVisitor;
 import com.oracle.svm.core.log.Log;
@@ -179,7 +180,8 @@ public Object promoteAlignedObject(Object original, AlignedHeapChunk.AlignedHead
             return space.copyAlignedObject(original, originalSpace);
         }
         assert originalSpace == space;
-        Word header = ObjectHeader.readHeaderFromObject(original);
+        ObjectHeader oh = Heap.getHeap().getObjectHeader();
+        Word header = oh.readHeaderFromObject(original);
         if (ObjectHeaderImpl.isMarkedHeader(header)) {
             return original;
         }
@@ -193,7 +195,7 @@ public Object promoteAlignedObject(Object original, AlignedHeapChunk.AlignedHead
              * object's size. The easiest way to handle this is to copy the object.
              */
             result = space.copyAlignedObject(original, originalSpace);
-            assert !ObjectHeaderImpl.hasIdentityHashFromAddressInline(ObjectHeader.readHeaderFromObject(result));
+            assert !ObjectHeaderImpl.hasIdentityHashFromAddressInline(oh.readHeaderFromObject(result));
         }
         ObjectHeaderImpl.setMarked(result);
         markStack.push(result);

substratevm/src/com.oracle.svm.core.genscavenge/src/com/oracle/svm/core/genscavenge/GreyToBlackObjRefVisitor.java

@@ -31,7 +31,6 @@
 import com.oracle.svm.core.AlwaysInline;
 import com.oracle.svm.core.Uninterruptible;
 import com.oracle.svm.core.genscavenge.remset.RememberedSet;
-import com.oracle.svm.core.heap.ObjectHeader;
 import com.oracle.svm.core.heap.ObjectReferenceVisitor;
 import com.oracle.svm.core.heap.ReferenceAccess;
 import com.oracle.svm.core.hub.LayoutEncoding;
@@ -91,7 +90,7 @@ public boolean visitObjectReferenceInline(Pointer objRef, int innerOffset, boole
         // This is the most expensive check as it accesses the heap fairly randomly, which results
         // in a lot of cache misses.
         ObjectHeaderImpl ohi = ObjectHeaderImpl.getObjectHeaderImpl();
-        Word header = ObjectHeader.readHeaderFromPointer(p);
+        Word header = ohi.readHeaderFromPointer(p);
         if (GCImpl.getGCImpl().isCompleteCollection() || !RememberedSet.get().hasRememberedSet(header)) {
 
             if (ObjectHeaderImpl.isForwardedHeader(header)) {

substratevm/src/com.oracle.svm.core.genscavenge/src/com/oracle/svm/core/genscavenge/HeapImpl.java

@@ -867,7 +867,7 @@ public int maxInvocationCount() {
         @RestrictHeapAccess(access = RestrictHeapAccess.Access.NO_ALLOCATION, reason = "Must not allocate while printing diagnostics.")
         public void printDiagnostics(Log log, ErrorContext context, int maxDiagnosticLevel, int invocationCount) {
             log.string("Heap settings and statistics:").indent(true);
-            log.string("Reserved object header bits: 0b").number(Heap.getHeap().getObjectHeader().getReservedBitsMask(), 2, false).newline();
+            log.string("Reserved hub pointer bits: 0b").number(Heap.getHeap().getObjectHeader().getReservedHubBitsMask(), 2, false).newline();
 
             log.string("Aligned chunk size: ").unsigned(HeapParameters.getAlignedHeapChunkSize()).newline();
             log.string("Large array threshold: ").unsigned(HeapParameters.getLargeArrayThreshold()).newline();

substratevm/src/com.oracle.svm.core.genscavenge/src/com/oracle/svm/core/genscavenge/HeapVerifier.java

@@ -35,6 +35,7 @@
 import com.oracle.svm.core.genscavenge.AlignedHeapChunk.AlignedHeader;
 import com.oracle.svm.core.genscavenge.UnalignedHeapChunk.UnalignedHeader;
 import com.oracle.svm.core.genscavenge.remset.RememberedSet;
+import com.oracle.svm.core.heap.Heap;
 import com.oracle.svm.core.heap.ObjectHeader;
 import com.oracle.svm.core.heap.ObjectReferenceVisitor;
 import com.oracle.svm.core.heap.ObjectVisitor;
@@ -241,7 +242,8 @@ private static boolean verifyObject(Object obj, AlignedHeader aChunk, UnalignedH
             return false;
         }
 
-        Word header = ObjectHeader.readHeaderFromPointer(ptr);
+        ObjectHeader oh = Heap.getHeap().getObjectHeader();
+        Word header = oh.readHeaderFromPointer(ptr);
         if (ObjectHeaderImpl.isProducedHeapChunkZapped(header) || ObjectHeaderImpl.isConsumedHeapChunkZapped(header)) {
             Log.log().string("Object ").zhex(ptr).string(" has a zapped header: ").zhex(header).newline();
             return false;
@@ -352,7 +354,8 @@ private static boolean verifyReference(Object parentObject, Pointer reference, P
             return false;
         }
 
-        Word header = ObjectHeader.readHeaderFromPointer(referencedObject);
+        ObjectHeader oh = Heap.getHeap().getObjectHeader();
+        Word header = oh.readHeaderFromPointer(referencedObject);
         if (!ObjectHeaderImpl.getObjectHeaderImpl().isEncodedObjectHeader(header)) {
             Log.log().string("Object reference at ").zhex(reference).string(" does not point to a Java object or the object header of the Java object is invalid: ").zhex(referencedObject)
                             .string(". ");