Mercurial > hg > graal-compiler

changeset 10800:69e305a5cf09

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Introduce new read opcode that allows compressed oops and read barriers
author Christos Kotselidis <christos.kotselidis@oracle.com>
date Wed, 17 Jul 2013 19:52:20 +0200
parents a84634196540
children 4bfbd4be6e7a
files graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/WriteBarrierSnippets.java graal/com.oracle.graal.word/src/com/oracle/graal/word/Pointer.java graal/com.oracle.graal.word/src/com/oracle/graal/word/Word.java graal/com.oracle.graal.word/src/com/oracle/graal/word/phases/WordTypeRewriterPhase.java
diffstat 4 files changed, 25 insertions(+), 28 deletions(-) [+]
line wrap: on
line diff
--- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/WriteBarrierSnippets.java	Wed Jul 17 19:31:46 2013 +0200
+++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/WriteBarrierSnippets.java	Wed Jul 17 19:52:20 2013 +0200
@@ -118,7 +118,7 @@
             // If the previous value has to be loaded (before the write), the load is issued.
             // The load is always issued except the cases of CAS and referent field.
             if (probability(LIKELY_PROBABILITY, doLoad)) {
-                previousOop = (Word) Word.fromObject(field.readObjectCompressed(0));
+                previousOop = (Word) Word.fromObject(field.readObject(0, 0, true));
                 if (trace) {
                     log(trace, "[%d] G1-Pre Thread %p Previous Object %p\n ", gcCycle, thread.rawValue(), previousOop.rawValue());
                     verifyOop(previousOop.toObject());
@@ -225,7 +225,7 @@
 
         for (int i = startIndex; i < length; i++) {
             Word address = (Word) Word.fromObject(dest).add(header).add(Word.unsigned(i * (long) scale));
-            oop = (Word) Word.fromObject(address.readObjectCompressed(0));
+            oop = (Word) Word.fromObject(address.readObject(0, 0, true));
             if (oop.notEqual(0)) {
                 if (indexValue.notEqual(0)) {
                     Word nextIndex = indexValue.subtract(wordSize());
--- a/graal/com.oracle.graal.word/src/com/oracle/graal/word/Pointer.java	Wed Jul 17 19:31:46 2013 +0200
+++ b/graal/com.oracle.graal.word/src/com/oracle/graal/word/Pointer.java	Wed Jul 17 19:52:20 2013 +0200
@@ -610,17 +610,19 @@
     Object readObject(WordBase offset);
 
     /**
-     * Reads the memory at address {@code (this + offset)} and uncompresses it. Both the base
-     * address and offset are in bytes.
+     * Reads the memory at address {@code (this + offset)}. This particular access can allow
+     * decompression and read barriers (G1 referent field).
      * <p>
      * The offset is always treated as a {@link Signed} value. However, the static type is
      * {@link WordBase} to avoid the frequent casts to of {@link Unsigned} values (where the caller
      * knows that the highest-order bit of the unsigned value is never used).
      * 
      * @param offset the signed offset for the memory access
+     * @param barrierType the type of the read barrier to be added
+     * @param compress whether or not the object is a decompression candidate
      * @return the result of the memory access
      */
-    Object readObjectCompressed(WordBase offset);
+    Object readObject(WordBase offset, int barrierType, boolean compress);
 
     /**
      * Reads the memory at address {@code (this + offset)}. Both the base address and offset are in
@@ -704,13 +706,15 @@
     Object readObject(int offset);
 
     /**
-     * Reads the memory at address {@code (this + offset)} and decompressed it. Both the base
-     * address and offset are in bytes.
+     * Reads the memory at address {@code (this + offset)}. This particular access can be
+     * parameterized to allow decompression and read barriers (G1 referent field).
      * 
      * @param offset the signed offset for the memory access
+     * @param barrierType the type of the read barrier to be added
+     * @param compress whether or not the object is a decompression candidate
      * @return the result of the memory access
      */
-    Object readObjectCompressed(int offset);
+    Object readObject(int offset, int barrierType, boolean compress);
 
     /**
      * Writes the memory at address {@code (this + offset)}. Both the base address and offset are in
--- a/graal/com.oracle.graal.word/src/com/oracle/graal/word/Word.java	Wed Jul 17 19:31:46 2013 +0200
+++ b/graal/com.oracle.graal.word/src/com/oracle/graal/word/Word.java	Wed Jul 17 19:52:20 2013 +0200
@@ -59,7 +59,7 @@
          COMPARISON,
          NOT,
          READ,
-         READ_COMPRESSED,
+         READ_HEAP,
          WRITE,
          INITIALIZE,
          ZERO,
@@ -880,9 +880,8 @@
     @Operation(opcode = Opcode.READ)
     public native Object readObject(WordBase offset);
 
-    @Override
-    @Operation(opcode = Opcode.READ_COMPRESSED)
-    public native Object readObjectCompressed(WordBase offset);
+    @Operation(opcode = Opcode.READ_HEAP)
+    public native Object readObject(WordBase offset, int barrierType, boolean compress);
 
     @Override
     @Operation(opcode = Opcode.READ)
@@ -938,10 +937,9 @@
         return readObject(signed(offset));
     }
 
-    @Override
-    @Operation(opcode = Opcode.READ_COMPRESSED)
-    public Object readObjectCompressed(int offset) {
-        return readObjectCompressed(signed(offset));
+    @Operation(opcode = Opcode.READ_HEAP)
+    public Object readObject(int offset, int barrierType, boolean compress) {
+        return readObject(signed(offset), barrierType, compress);
     }
 
     @Override
--- a/graal/com.oracle.graal.word/src/com/oracle/graal/word/phases/WordTypeRewriterPhase.java	Wed Jul 17 19:31:46 2013 +0200
+++ b/graal/com.oracle.graal.word/src/com/oracle/graal/word/phases/WordTypeRewriterPhase.java	Wed Jul 17 19:52:20 2013 +0200
@@ -175,19 +175,14 @@
                         } else {
                             location = makeLocation(graph, arguments.get(1), readKind, arguments.get(2));
                         }
-                        replace(invoke, readOp(graph, arguments.get(0), invoke, location, false));
+                        replace(invoke, readOp(graph, arguments.get(0), invoke, location, 0, false));
                         break;
                     }
-                    case READ_COMPRESSED: {
-                        assert arguments.size() == 2 || arguments.size() == 3;
+                    case READ_HEAP: {
+                        assert arguments.size() == 4;
                         Kind readKind = asKind(callTargetNode.returnType());
-                        LocationNode location;
-                        if (arguments.size() == 2) {
-                            location = makeLocation(graph, arguments.get(1), readKind, ANY_LOCATION);
-                        } else {
-                            location = makeLocation(graph, arguments.get(1), readKind, arguments.get(2));
-                        }
-                        replace(invoke, readOp(graph, arguments.get(0), invoke, location, true));
+                        LocationNode location = makeLocation(graph, arguments.get(1), readKind, ANY_LOCATION);
+                        replace(invoke, readOp(graph, arguments.get(0), invoke, location, arguments.get(2).asConstant().asInt(), arguments.get(3).asConstant().asInt() == 0 ? false : true));
                         break;
                     }
                     case WRITE:
@@ -328,8 +323,8 @@
         return IndexedLocationNode.create(locationIdentity, readKind, 0, offset, graph, 1);
     }
 
-    private static ValueNode readOp(StructuredGraph graph, ValueNode base, Invoke invoke, LocationNode location, boolean compress) {
-        ReadNode read = graph.add(new ReadNode(base, location, invoke.asNode().stamp(), WriteBarrierType.NONE, compress));
+    private static ValueNode readOp(StructuredGraph graph, ValueNode base, Invoke invoke, LocationNode location, int barrierType, boolean compress) {
+        ReadNode read = graph.add(new ReadNode(base, location, invoke.asNode().stamp(), WriteBarrierType.values()[barrierType], compress));
         graph.addBeforeFixed(invoke.asNode(), read);
         // The read must not float outside its block otherwise it may float above an explicit zero
         // check on its base address