Wasm: write more info about classes in DWARF

core/src/main/java/org/teavm/backend/wasm/dwarf/DwarfConstants.java

@@ -24,6 +24,7 @@ public final class DwarfConstants {
     public static final int DW_TAG_FORMAL_PARAMETER = 0x05;
     public static final int DW_TAG_POINTER_TYPE = 0x0F;
     public static final int DW_TAG_COMPILE_UNIT = 0x11;
+    public static final int DW_TAG_INHERITANCE = 0x1C;
     public static final int DW_TAG_BASE_TYPE = 0x24;
     public static final int DW_TAG_SUBPROGRAM = 0x2E;
     public static final int DW_TAG_VARIABLE = 0x34;
@@ -72,6 +73,8 @@ public final class DwarfConstants {
     public static final int DW_FORM_FLAG_PRESENT = 0x19;
     public static final int DW_FORM_LINE_STRP = 0x1F;
 
+    public static final int DW_OP_ADDR = 0x03;
+    public static final int DW_OP_STACK_VALUE = 0x9F;
     public static final int DW_OP_WASM_LOCATION = 0xED;
 
     public static final int DW_LNS_COPY = 0x01;

core/src/main/java/org/teavm/backend/wasm/dwarf/DwarfInfoWriter.java

@@ -20,6 +20,7 @@ import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_CHILDREN_YES;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Objects;
 import java.util.function.Consumer;
 import org.teavm.backend.wasm.dwarf.blob.BinaryDataConsumer;
 import org.teavm.backend.wasm.dwarf.blob.Blob;
@@ -115,6 +116,7 @@ public class DwarfInfoWriter {
     }
 
     public DwarfInfoWriter mark(DwarfPlaceholder placeholder) {
+        Objects.requireNonNull(placeholder);
         placements.add(new Placement(output.ptr()) {
             @Override
             void write(Blob blob) {

core/src/main/java/org/teavm/backend/wasm/generate/DwarfClassGenerator.java

@@ -22,18 +22,25 @@ import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_ATE_UTF;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_AT_BYTE_SIZE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_AT_DECLARATION;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_AT_ENCODING;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_AT_LOCATION;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_AT_NAME;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_AT_TYPE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_DATA1;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_DATA2;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_EXPRLOC;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_FLAG_PRESENT;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_REF4;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_STRP;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_OP_ADDR;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_OP_STACK_VALUE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_BASE_TYPE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_CLASS_TYPE;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_INHERITANCE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_NAMESPACE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_POINTER_TYPE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_SUBPROGRAM;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_UNSPECIFIED_TYPE;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_VARIABLE;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
@@ -57,12 +64,15 @@ public class DwarfClassGenerator {
     private final DwarfStrings strings;
     private DwarfAbbreviation nsAbbrev;
     private DwarfAbbreviation classTypeAbbrev;
+    private DwarfAbbreviation inheritanceAbbrev;
     private DwarfAbbreviation methodAbbrev;
     private DwarfPlaceholder[] primitiveTypes = new DwarfPlaceholder[PrimitiveType.values().length];
     private DwarfPlaceholder unspecifiedType;
     private DwarfAbbreviation baseTypeAbbrev;
     private DwarfAbbreviation pointerAbbrev;
+    private DwarfAbbreviation variableAbbrev;
     private List<Runnable> postponedWrites = new ArrayList<>();
+    private ClassType classClass;
 
     public DwarfClassGenerator(DwarfInfoWriter writer, DwarfStrings strings) {
         this.writer = writer;
@@ -99,10 +109,12 @@ public class DwarfClassGenerator {
     }
 
     public void write() {
+        classClass = getClass("java.lang.Class");
         root.writeChildren();
         for (var subprogram : rootSubprograms) {
             subprogram.write();
         }
+        flushTypes();
     }
 
     private DwarfAbbreviation getMethodAbbrev() {
@@ -128,11 +140,21 @@ public class DwarfClassGenerator {
         if (classTypeAbbrev == null) {
             classTypeAbbrev = writer.abbreviation(DW_TAG_CLASS_TYPE, true, data -> {
                 data.writeLEB(DW_AT_NAME).writeLEB(DW_FORM_STRP);
+                data.writeLEB(DW_AT_BYTE_SIZE).writeLEB(DW_FORM_DATA2);
             });
         }
         return classTypeAbbrev;
     }
 
+    private DwarfAbbreviation getInheritanceAbbrev() {
+        if (inheritanceAbbrev == null) {
+            inheritanceAbbrev = writer.abbreviation(DW_TAG_INHERITANCE, false, data -> {
+                data.writeLEB(DW_AT_TYPE).writeLEB(DW_FORM_REF4);
+            });
+        }
+        return inheritanceAbbrev;
+    }
+
     public DwarfPlaceholder getTypePtr(VariableType type) {
         switch (type) {
             case INT:
@@ -169,7 +191,7 @@ public class DwarfClassGenerator {
     }
 
     private DwarfPlaceholder getClassType(String name) {
-        return getClass(name).getPointerPtr();
+        return getClass(name).ptr;
     }
 
     private DwarfPlaceholder getPrimitivePtr(ValueType.Primitive type) {
@@ -256,6 +278,17 @@ public class DwarfClassGenerator {
         return pointerAbbrev;
     }
 
+    private DwarfAbbreviation getVariableAbbrev() {
+        if (variableAbbrev == null) {
+            variableAbbrev = writer.abbreviation(DW_TAG_VARIABLE, false, blob -> {
+                blob.writeLEB(DW_AT_NAME).writeLEB(DW_FORM_STRP);
+                blob.writeLEB(DW_AT_TYPE).writeLEB(DW_FORM_REF4);
+                blob.writeLEB(DW_AT_LOCATION).writeLEB(DW_FORM_EXPRLOC);
+            });
+        }
+        return variableAbbrev;
+    }
+
     public class Namespace {
         public final String name;
         final Map<String, Namespace> namespaces = new LinkedHashMap<>();
@@ -295,16 +328,31 @@ public class DwarfClassGenerator {
         final DwarfPlaceholder ptr;
         private DwarfPlaceholder pointerPtr;
         final Map<MethodDescriptor, Subprogram> subprograms = new LinkedHashMap<>();
+        private ClassType superclass;
+        private int size;
+        private int pointer = -1;
 
         private ClassType(String name) {
             ptr = writer.placeholder(4);
             this.name = name;
         }
 
+        public void setSuperclass(ClassType superclass) {
+            this.superclass = superclass;
+        }
+
         public Subprogram getSubprogram(MethodDescriptor desc) {
             return subprograms.computeIfAbsent(desc, d -> new Subprogram(d.getName(), desc));
         }
 
+        public void setSize(int size) {
+            this.size = size;
+        }
+
+        public void setPointer(int pointer) {
+            this.pointer = pointer;
+        }
+
         public DwarfPlaceholder getPointerPtr() {
             if (pointerPtr == null) {
                 pointerPtr = writer.placeholder(4);
@@ -315,6 +363,10 @@ public class DwarfClassGenerator {
         private void write() {
             writer.mark(ptr).tag(getClassTypeAbbrev());
             writer.writeInt(strings.stringRef(name));
+            writer.writeShort(size);
+            if (superclass != null) {
+                writer.tag(getInheritanceAbbrev()).ref(superclass.ptr, Blob::writeInt);
+            }
             for (var child : subprograms.values()) {
                 child.write();
             }
@@ -322,6 +374,15 @@ public class DwarfClassGenerator {
                 writer.mark(pointerPtr).tag(getPointerAbbrev());
                 writer.ref(ptr, Blob::writeInt);
             }
+            if (pointer >= 0) {
+                writer.tag(getVariableAbbrev());
+                writer.writeInt(strings.stringRef("__class__"));
+                writer.ref(classClass.ptr, Blob::writeInt);
+                var ops = new Blob();
+                ops.writeByte(DW_OP_ADDR).writeInt(pointer).writeByte(DW_OP_STACK_VALUE);
+                writer.writeLEB(ops.size());
+                ops.newReader(writer::write).readRemaining();
+            }
             writer.emptyTag();
         }
     }

core/src/main/java/org/teavm/backend/wasm/generate/DwarfFunctionGenerator.java

@@ -25,6 +25,7 @@ import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_ADDR;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_EXPRLOC;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_REF4;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_FORM_STRP;
+import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_OP_STACK_VALUE;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_OP_WASM_LOCATION;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_FORMAL_PARAMETER;
 import static org.teavm.backend.wasm.dwarf.DwarfConstants.DW_TAG_SUBPROGRAM;
@@ -33,6 +34,7 @@ import org.teavm.backend.wasm.dwarf.DwarfAbbreviation;
 import org.teavm.backend.wasm.dwarf.blob.Blob;
 import org.teavm.backend.wasm.dwarf.blob.Marker;
 import org.teavm.backend.wasm.model.WasmFunction;
+import org.teavm.model.util.VariableType;
 
 public class DwarfFunctionGenerator {
     private DwarfClassGenerator classGen;
@@ -114,6 +116,9 @@ public class DwarfFunctionGenerator {
 
             var operations = new Blob();
             operations.writeByte(DW_OP_WASM_LOCATION).writeByte(0).writeLEB(i + 1);
+            if (local.getJavaType() == VariableType.OBJECT) {
+                operations.writeByte(DW_OP_STACK_VALUE);
+            }
             writer.writeLEB(operations.size());
             operations.newReader(writer::write).readRemaining();
         }

core/src/main/java/org/teavm/backend/wasm/generate/WasmClassGenerator.java

@@ -179,12 +179,22 @@ public class WasmClassGenerator {
             var cls = classSource.get(className);
 
             if (cls != null) {
-                calculateLayout(cls, binaryData);
+                DwarfClassGenerator.ClassType dwarfClass;
+                if (dwarfClassGenerator != null) {
+                    dwarfClass = dwarfClassGenerator.getClass(className);
+                    dwarfClass.setSuperclass(cls.getParent() != null
+                            ? dwarfClassGenerator.getClass(cls.getParent())
+                            : null);
+                } else {
+                    dwarfClass = null;
+                }
+                calculateLayout(cls, binaryData, dwarfClass);
                 if (binaryData.start >= 0) {
                     binaryData.start = binaryWriter.append(createStructure(binaryData));
                 }
-                if (dwarfClassGenerator != null) {
+                if (dwarfClass != null) {
-                    dwarfClassGenerator.getClass(className);
+                    dwarfClass.setSize(binaryData.size);
+                    dwarfClass.setPointer(binaryData.start);
                 }
             }
         } else if (type instanceof ValueType.Array) {
@@ -486,7 +496,7 @@ public class WasmClassGenerator {
         return binaryDataMap.get(type).function;
     }
 
-    private void calculateLayout(ClassReader cls, ClassBinaryData data) {
+    private void calculateLayout(ClassReader cls, ClassBinaryData data, DwarfClassGenerator.ClassType dwarfClass) {
         if (cls.getName().equals(Structure.class.getName()) || cls.getName().equals(Address.class.getName())) {
             data.size = 0;
             data.start = -1;