Update vararg handling to match JDK22

Author: Solène Husseini

substratevm/src/com.oracle.svm.core.foreign/src/com/oracle/svm/core/foreign/AbiUtils.java

@@ -511,9 +511,22 @@ protected CallingSequence makeCallingSequence(MethodType type, FunctionDescripto
         @Override
         protected List<Adapter.Adaptation> generateAdaptations(NativeEntryPointInfo nep) {
             var adaptations = super.generateAdaptations(nep);
-            /* Drop the rax parametersAssignment */
-            assert adaptations.get(adaptations.size() - 1) == null;
-            adaptations.set(adaptations.size() - 1, Adapter.drop());
+            var assignments = nep.parametersAssignment();
+
+            if (assignments.length > 0) {
+                final int last = assignments.length - 1;
+                if (assignments[last].equals(X86_64Architecture.Regs.rax)) {
+                    /*
+                     * This branch is only taken when the function is variadic, that is when rax is
+                     * passed as an additional pseudo-parameter, where it will contain the number of
+                     * XMM registers passed as arguments. However, we need to remove the rax
+                     * assignment since rax will already be assigned separately in
+                     * SubstrateAMD64RegisterConfig.getCallingConvention and later used in
+                     * SubstrateAMD64NodeLIRBuilder.visitInvokeArguments.
+                     */
+                    adaptations.set(last, Adapter.drop());
+                }
+            }
             return adaptations;
         }
 

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/graal/snippets/CFunctionSnippets.java

@@ -30,15 +30,12 @@
 
 import org.graalvm.compiler.api.replacements.Snippet;
 import org.graalvm.compiler.api.replacements.Snippet.ConstantParameter;
-import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;
 import org.graalvm.compiler.graph.Node;
 import org.graalvm.compiler.nodes.FixedNode;
 import org.graalvm.compiler.nodes.FixedWithNextNode;
 import org.graalvm.compiler.nodes.Invoke;
 import org.graalvm.compiler.nodes.InvokeNode;
 import org.graalvm.compiler.nodes.InvokeWithExceptionNode;
-import org.graalvm.compiler.nodes.ValueNode;
-import org.graalvm.compiler.nodes.extended.ForeignCallNode;
 import org.graalvm.compiler.nodes.extended.MembarNode;
 import org.graalvm.compiler.nodes.spi.LoweringTool;
 import org.graalvm.compiler.options.OptionValues;
@@ -50,7 +47,6 @@
 import org.graalvm.compiler.replacements.Snippets;
 import org.graalvm.nativeimage.Platforms;
 import org.graalvm.nativeimage.c.struct.SizeOf;
-import org.graalvm.nativeimage.c.type.CIntPointer;
 import org.graalvm.nativeimage.impl.InternalPlatform;
 import org.graalvm.word.LocationIdentity;
 
@@ -62,7 +58,6 @@
 import com.oracle.svm.core.graal.nodes.VerificationMarkerNode;
 import com.oracle.svm.core.graal.stackvalue.LoweredStackValueNode;
 import com.oracle.svm.core.graal.stackvalue.StackValueNode.StackSlotIdentity;
-import com.oracle.svm.core.nodes.CFunctionCaptureNode;
 import com.oracle.svm.core.nodes.CFunctionEpilogueNode;
 import com.oracle.svm.core.nodes.CFunctionPrologueDataNode;
 import com.oracle.svm.core.nodes.CFunctionPrologueNode;
@@ -98,7 +93,6 @@
 public final class CFunctionSnippets extends SubstrateTemplates implements Snippets {
 
     private final SnippetInfo prologue;
-    private final SnippetInfo capture;
     private final SnippetInfo epilogue;
 
     /**
@@ -123,14 +117,6 @@ private static CPrologueData prologueSnippet(@ConstantParameter int newThreadSta
         return CFunctionPrologueDataNode.cFunctionPrologueData(anchor, newThreadStatus);
     }
 
-    @Node.NodeIntrinsic(value = ForeignCallNode.class)
-    public static native void callCaptureFunction(@Node.ConstantNodeParameter ForeignCallDescriptor descriptor, int states, CIntPointer captureBuffer);
-
-    @Snippet
-    private static void captureSnippet(@ConstantParameter ForeignCallDescriptor captureFunction, int statesToCapture, CIntPointer captureBuffer) {
-        callCaptureFunction(captureFunction, statesToCapture, captureBuffer);
-    }
-
     @Snippet
     private static void epilogueSnippet(@ConstantParameter int oldThreadStatus) {
         if (SubstrateOptions.MultiThreaded.getValue()) {
@@ -157,11 +143,9 @@ private static void epilogueSnippet(@ConstantParameter int oldThreadStatus) {
         super(options, providers);
 
         this.prologue = snippet(providers, CFunctionSnippets.class, "prologueSnippet");
-        this.capture = snippet(providers, CFunctionSnippets.class, "captureSnippet");
         this.epilogue = snippet(providers, CFunctionSnippets.class, "epilogueSnippet");
 
         lowerings.put(CFunctionPrologueNode.class, new CFunctionPrologueLowering());
-        lowerings.put(CFunctionCaptureNode.class, new CFunctionCaptureLowering());
         lowerings.put(CFunctionEpilogueNode.class, new CFunctionEpilogueLowering());
     }
 
@@ -193,27 +177,6 @@ public void lower(CFunctionPrologueNode node, LoweringTool tool) {
         }
     }
 
-    class CFunctionCaptureLowering implements NodeLoweringProvider<CFunctionCaptureNode> {
-        @Override
-        public void lower(CFunctionCaptureNode node, LoweringTool tool) {
-            if (tool.getLoweringStage() != LoweringTool.StandardLoweringStage.LOW_TIER) {
-                return;
-            }
-
-            ValueNode statesToCapture = node.getStatesToCapture();
-            ForeignCallDescriptor captureFunction = node.getCaptureFunction();
-            ValueNode buffer = node.getCaptureBuffer();
-            Arguments args = new Arguments(capture, node.graph().getGuardsStage(), tool.getLoweringStage());
-            args.addConst("captureFunction", captureFunction);
-            args.add("statesToCapture", statesToCapture);
-            args.add("captureBuffer", buffer);
-
-            SnippetTemplate template = template(tool, node, args);
-            template.setMayRemoveLocation(true);
-            template.instantiate(tool.getMetaAccess(), node, SnippetTemplate.DEFAULT_REPLACER, args);
-        }
-    }
-
     class CFunctionEpilogueLowering implements NodeLoweringProvider<CFunctionEpilogueNode> {
         @Override
         public void lower(CFunctionEpilogueNode node, LoweringTool tool) {

substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/nodes/CFunctionCaptureNode.java

@@ -37,8 +37,10 @@
 import org.graalvm.compiler.nodeinfo.NodeInfo;
 import org.graalvm.compiler.nodes.FixedWithNextNode;
 import org.graalvm.compiler.nodes.ValueNode;
+import org.graalvm.compiler.nodes.extended.ForeignCallNode;
 import org.graalvm.compiler.nodes.memory.SingleMemoryKill;
 import org.graalvm.compiler.nodes.spi.Lowerable;
+import org.graalvm.compiler.nodes.spi.LoweringTool;
 import org.graalvm.word.LocationIdentity;
 
 /**
@@ -76,15 +78,13 @@ public LocationIdentity getKilledLocationIdentity() {
         return LocationIdentity.any();
     }
 
-    public ForeignCallDescriptor getCaptureFunction() {
-        return captureFunction;
-    }
-
-    public ValueNode getStatesToCapture() {
-        return statesToCapture;
-    }
+    @Override
+    public void lower(LoweringTool tool) {
+        if (tool.getLoweringStage() != LoweringTool.StandardLoweringStage.LOW_TIER) {
+            return;
+        }
 
-    public ValueNode getCaptureBuffer() {
-        return captureBuffer;
+        final ForeignCallNode call = graph().add(new ForeignCallNode(captureFunction, statesToCapture, captureBuffer));
+        graph().replaceFixedWithFixed(this, call);
     }
 }