wasm gc: minor optimizations; make initializer functions Wasm start function; fix compilation; remove debugging output

core/src/main/java/org/teavm/backend/wasm/WasmGCModuleGenerator.java

@@ -17,17 +17,6 @@ package org.teavm.backend.wasm;
 
 import org.teavm.backend.wasm.generate.gc.WasmGCDeclarationsGenerator;
 import org.teavm.backend.wasm.model.WasmFunction;
-import org.teavm.backend.wasm.model.WasmGlobal;
-import org.teavm.backend.wasm.model.WasmLocal;
-import org.teavm.backend.wasm.model.WasmType;
-import org.teavm.backend.wasm.model.expression.WasmCall;
-import org.teavm.backend.wasm.model.expression.WasmCallReference;
-import org.teavm.backend.wasm.model.expression.WasmDrop;
-import org.teavm.backend.wasm.model.expression.WasmExpression;
-import org.teavm.backend.wasm.model.expression.WasmFunctionReference;
-import org.teavm.backend.wasm.model.expression.WasmGetGlobal;
-import org.teavm.backend.wasm.model.expression.WasmGetLocal;
-import org.teavm.backend.wasm.model.expression.WasmSetGlobal;
 import org.teavm.backend.wasm.runtime.StringInternPool;
 import org.teavm.backend.wasm.runtime.gc.WasmGCSupport;
 import org.teavm.model.MethodReference;
@@ -35,8 +24,6 @@ import org.teavm.model.ValueType;
 
 public class WasmGCModuleGenerator {
     private WasmGCDeclarationsGenerator declarationsGenerator;
-    private WasmFunction initializer;
-    private WasmGlobal initializerRef;
 
     public WasmGCModuleGenerator(WasmGCDeclarationsGenerator declarationsGenerator) {
         this.declarationsGenerator = declarationsGenerator;
@@ -44,166 +31,66 @@ public class WasmGCModuleGenerator {
 
     public void generate() {
         declarationsGenerator.generate();
-        if (initializer != null) {
-            fillInitializer();
-        }
+        createInitializer();
     }
 
-    private void fillInitializer() {
-        declarationsGenerator.contributeToInitializer(initializer);
-    }
 
     public WasmFunction generateMainFunction(String entryPoint) {
-        var mainFunction = declarationsGenerator.functions().forStaticMethod(new MethodReference(entryPoint,
+        return declarationsGenerator.functions().forStaticMethod(new MethodReference(entryPoint,
                 "main", ValueType.parse(String[].class), ValueType.VOID));
-        var stringArrayType = declarationsGenerator.typeMapper()
-                .mapType(ValueType.parse(String[].class));
-        var mainFunctionCaller = new WasmFunction(declarationsGenerator.functionTypes.of(null, stringArrayType));
-        var argsLocal = new WasmLocal(stringArrayType, "args");
-        declarationsGenerator.module.functions.add(mainFunctionCaller);
-        mainFunctionCaller.getBody().add(callInitializer());
-
-        var callToMainFunction = new WasmCall(mainFunction, new WasmGetLocal(argsLocal));
-        mainFunctionCaller.getBody().add(callToMainFunction);
-
-        return mainFunctionCaller;
     }
 
     public WasmFunction generateCreateStringBuilderFunction() {
-        var function = declarationsGenerator.functions().forStaticMethod(new MethodReference(
+        return declarationsGenerator.functions().forStaticMethod(new MethodReference(
                 WasmGCSupport.class, "createStringBuilder", StringBuilder.class));
-        var caller = new WasmFunction(function.getType());
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmCall(function));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     public WasmFunction generateCreateStringArrayFunction() {
-        var function = declarationsGenerator.functions().forStaticMethod(new MethodReference(
+        return declarationsGenerator.functions().forStaticMethod(new MethodReference(
                 WasmGCSupport.class, "createStringArray", int.class, String[].class));
-        var caller = new WasmFunction(function.getType());
-        var sizeLocal = new WasmLocal(WasmType.INT32, "length");
-        caller.add(sizeLocal);
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmCall(function, new WasmGetLocal(sizeLocal)));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     public WasmFunction generateAppendCharFunction() {
-        var function = declarationsGenerator.functions().forInstanceMethod(new MethodReference(
+        return declarationsGenerator.functions().forInstanceMethod(new MethodReference(
                 StringBuilder.class, "append", char.class, StringBuilder.class));
-        var stringBuilderType = declarationsGenerator.typeMapper().mapType(ValueType.parse(StringBuilder.class));
-        var caller = new WasmFunction(declarationsGenerator.functionTypes.of(null, stringBuilderType, WasmType.INT32));
-        var stringBuilderLocal = new WasmLocal(stringBuilderType, "stringBuilder");
-        var codeLocal = new WasmLocal(WasmType.INT32, "charCode");
-        caller.add(stringBuilderLocal);
-        caller.add(codeLocal);
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmDrop(new WasmCall(function, new WasmGetLocal(stringBuilderLocal),
-                new WasmGetLocal(codeLocal))));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     public WasmFunction generateBuildStringFunction() {
-        var function = declarationsGenerator.functions().forInstanceMethod(new MethodReference(
+        return declarationsGenerator.functions().forInstanceMethod(new MethodReference(
                 StringBuilder.class, "toString", String.class));
-        var stringBuilderType = declarationsGenerator.typeMapper().mapType(ValueType.parse(StringBuilder.class));
-        var stringType = declarationsGenerator.typeMapper().mapType(ValueType.parse(String.class));
-        var caller = new WasmFunction(declarationsGenerator.functionTypes.of(stringType, stringBuilderType));
-        var stringBuilderLocal = new WasmLocal(stringBuilderType, "stringBuilder");
-        caller.add(stringBuilderLocal);
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmCall(function, new WasmGetLocal(stringBuilderLocal)));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     public WasmFunction generateSetToStringArrayFunction() {
-        var function = declarationsGenerator.functions().forStaticMethod(new MethodReference(
+        return declarationsGenerator.functions().forStaticMethod(new MethodReference(
                 WasmGCSupport.class, "setToStringArray", String[].class, int.class, String.class, void.class));
-        var stringArrayType = declarationsGenerator.typeMapper().mapType(ValueType.parse(String[].class));
-        var stringType = declarationsGenerator.typeMapper().mapType(ValueType.parse(String.class));
-        var caller = new WasmFunction(function.getType());
-        var arrayLocal = new WasmLocal(stringArrayType, "array");
-        var indexLocal = new WasmLocal(WasmType.INT32, "index");
-        var valueLocal = new WasmLocal(stringType, "string");
-        caller.add(arrayLocal);
-        caller.add(indexLocal);
-        caller.add(valueLocal);
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmCall(function, new WasmGetLocal(arrayLocal),
-                new WasmGetLocal(indexLocal), new WasmGetLocal(valueLocal)));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     public WasmFunction generateStringLengthFunction() {
-        var function = declarationsGenerator.functions().forInstanceMethod(new MethodReference(
+        return declarationsGenerator.functions().forInstanceMethod(new MethodReference(
                 String.class, "length", int.class));
-        var stringType = declarationsGenerator.typeMapper().mapType(ValueType.parse(String.class));
-        var caller = new WasmFunction(function.getType());
-        var stringLocal = new WasmLocal(stringType, "string");
-        caller.add(stringLocal);
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmCall(function, new WasmGetLocal(stringLocal)));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     public WasmFunction generateCharAtFunction() {
-        var function = declarationsGenerator.functions().forInstanceMethod(new MethodReference(
+        return declarationsGenerator.functions().forInstanceMethod(new MethodReference(
                 String.class, "charAt", int.class, char.class));
-        var stringType = declarationsGenerator.typeMapper().mapType(ValueType.parse(String.class));
-        var caller = new WasmFunction(function.getType());
-        var stringLocal = new WasmLocal(stringType, "string");
-        var indexLocal = new WasmLocal(WasmType.INT32, "index");
-        caller.add(stringLocal);
-        caller.add(indexLocal);
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmCall(function, new WasmGetLocal(stringLocal),
-                new WasmGetLocal(indexLocal)));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     public WasmFunction generateReportGarbageCollectedStringFunction() {
         var entryType = ValueType.object(StringInternPool.class.getName() + "$Entry");
-        var function = declarationsGenerator.functions().forStaticMethod(new MethodReference(
+        return declarationsGenerator.functions().forStaticMethod(new MethodReference(
                 StringInternPool.class.getName(),
                 "remove",
                 entryType,
                 ValueType.VOID
         ));
-        var caller = new WasmFunction(function.getType());
-        var entryLocal = new WasmLocal(declarationsGenerator.typeMapper().mapType(entryType));
-        caller.add(entryLocal);
-        caller.getBody().add(callInitializer());
-        caller.getBody().add(new WasmCall(function, new WasmGetLocal(entryLocal)));
-        declarationsGenerator.module.functions.add(caller);
-        return caller;
     }
 
     private void createInitializer() {
-        if (initializer != null) {
-            return;
-        }
         var functionType = declarationsGenerator.functionTypes.of(null);
-        initializer = new WasmFunction(functionType);
-        initializer.setReferenced(true);
+        var initializer = new WasmFunction(functionType);
         initializer.setName("teavm@initializer");
         declarationsGenerator.module.functions.add(initializer);
-        initializerRef = new WasmGlobal("teavm@initializerRef", functionType.getNonNullReference(),
-                new WasmFunctionReference(initializer));
-        declarationsGenerator.module.globals.add(initializerRef);
-        initializer.getBody().add(new WasmSetGlobal(initializerRef,
-                new WasmFunctionReference(declarationsGenerator.dummyInitializer())));
-    }
-
-    private WasmExpression callInitializer() {
-        createInitializer();
-        return new WasmCallReference(new WasmGetGlobal(initializerRef), declarationsGenerator.functionTypes.of(null));
+        declarationsGenerator.module.setStartFunction(initializer);
+        declarationsGenerator.contributeToInitializer(initializer);
     }
 }

core/src/main/java/org/teavm/backend/wasm/debug/DebugLinesBuilder.java

@@ -48,7 +48,6 @@ public class DebugLinesBuilder extends DebugSectionBuilder implements DebugLines
     public void location(String file, int line) {
         if (Objects.equals(file, this.file) && this.ptr != lastWrittenPtr && this.line != line) {
             if (this.ptr - lastWrittenPtr < 32 && Math.abs(line - this.line) <= 3) {
-                System.out.println(blob.ptr() + indent.toString() + "[user] ptr: " + this.ptr + ", line: " + line);
                 blob.writeByte(DebugConstants.LOC_USER + (this.ptr - lastWrittenPtr) + 32 * (line - this.line + 3));
                 this.line = line;
                 lastWrittenPtr = ptr;
@@ -59,12 +58,10 @@ public class DebugLinesBuilder extends DebugSectionBuilder implements DebugLines
             flushPtr();
             this.line = 1;
             this.file = file;
-            System.out.println(blob.ptr() + indent.toString() + "[file] " + file);
             blob.writeByte(DebugConstants.LOC_FILE).writeLEB(file != null ? files.filePtr(file) : 0);
         }
         if (this.line != line) {
             flushPtr();
-            System.out.println(blob.ptr() + indent.toString() + "[line] " + line);
             blob.writeByte(DebugConstants.LOC_LINE).writeSLEB(line - this.line);
             this.line = line;
         }
@@ -77,7 +74,6 @@ public class DebugLinesBuilder extends DebugSectionBuilder implements DebugLines
 
     private void flushPtr() {
         if (ptr != lastWrittenPtr) {
-            System.out.println(blob.ptr() + indent.toString() + "[ptr] " + ptr);
             blob.writeLEB(DebugConstants.LOC_PTR);
             blob.writeLEB(ptr - lastWrittenPtr);
             lastWrittenPtr = ptr;
@@ -87,7 +83,6 @@ public class DebugLinesBuilder extends DebugSectionBuilder implements DebugLines
     @Override
     public void start(MethodReference methodReference) {
         flushPtr();
-        System.out.println(blob.ptr() + indent.toString() + "[start] method: " + methodReference);
         indent.append(".");
         blob.writeLEB(DebugConstants.LOC_START);
         blob.writeLEB(methods.methodPtr(methodReference));
@@ -100,7 +95,6 @@ public class DebugLinesBuilder extends DebugSectionBuilder implements DebugLines
     public void end() {
         flushPtr();
         indent.setLength(indent.length() - 1);
-        System.out.println(blob.ptr() + indent.toString() + "[end]");
         blob.writeLEB(DebugConstants.LOC_END);
         if (!states.isEmpty()) {
             var state = states.pop();

core/src/main/java/org/teavm/backend/wasm/generate/common/methods/BaseWasmGenerationVisitor.java

@@ -132,6 +132,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
     private boolean async;
     protected WasmExpression result;
     protected List<WasmExpression> resultConsumer;
+    protected int blockLevel;
 
     public BaseWasmGenerationVisitor(BaseWasmGenerationContext context, MethodReference currentMethod,
             WasmFunction function, int firstVariable, boolean async) {
@@ -591,9 +592,11 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
     @Override
     public void visit(ConditionalStatement statement) {
         accept(statement.getCondition());
+        ++blockLevel;
         var conditional = new WasmConditional(forCondition(result));
         visitMany(statement.getConsequent(), conditional.getThenBlock().getBody());
         visitMany(statement.getAlternative(), conditional.getElseBlock().getBody());
+        --blockLevel;
         resultConsumer.add(conditional);
     }
 
@@ -616,6 +619,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
                 .max().orElse(0);
 
         var defaultBlock = new WasmBlock(false);
+        ++blockLevel;
         breakTargets.put(statement, defaultBlock);
         var oldBreakTarget = currentBreakTarget;
         currentBreakTarget = statement;
@@ -651,6 +655,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
         breakTargets.remove(statement);
         currentBreakTarget = oldBreakTarget;
 
+        --blockLevel;
         resultConsumer.add(wrapper);
     }
 
@@ -738,6 +743,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
         var wrapper = new WasmBlock(false);
         var loop = new WasmBlock(true);
 
+        ++blockLevel;
         continueTargets.put(statement, loop);
         breakTargets.put(statement, wrapper);
         var oldBreakTarget = currentBreakTarget;
@@ -765,6 +771,8 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
         } else {
             resultConsumer.add(loop);
         }
+
+        --blockLevel;
     }
 
     protected WasmExpression invocation(InvocationExpr expr, List<WasmExpression> resultConsumer, boolean willDrop) {
@@ -957,6 +965,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
     @Override
     public void visit(BlockStatement statement) {
         var block = new WasmBlock(false);
+        ++blockLevel;
 
         if (statement.getId() != null) {
             breakTargets.put(statement, block);
@@ -969,6 +978,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
         }
 
         resultConsumer.add(block);
+        --blockLevel;
     }
 
 
@@ -1053,9 +1063,15 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
         } else {
             result = null;
         }
-        var wasmStatement = new WasmReturn(result);
-        wasmStatement.setLocation(statement.getLocation());
-        resultConsumer.add(wasmStatement);
+        if (blockLevel == 0) {
+            if (result != null) {
+                resultConsumer.add(result);
+            }
+        } else {
+            var wasmStatement = new WasmReturn(result);
+            wasmStatement.setLocation(statement.getLocation());
+            resultConsumer.add(wasmStatement);
+        }
     }
 
     protected WasmExpression forceType(WasmExpression expression, ValueType type) {
@@ -1181,6 +1197,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
     protected void generateTry(List<TryCatchStatement> tryCatchStatements, List<Statement> protectedBody) {
         var throwableType = mapType(ValueType.object("java.lang.Throwable"));
         var innerCatchBlock = new WasmBlock(false);
+        ++blockLevel;
 
         var catchBlocks = new ArrayList<WasmBlock>();
         for (int i = 0; i < tryCatchStatements.size(); ++i) {
@@ -1247,6 +1264,7 @@ public abstract class BaseWasmGenerationVisitor implements StatementVisitor, Exp
 
         resultConsumer.add(outerCatchBlock);
         tempVars.release(exceptionVar);
+        --blockLevel;
     }
 
     protected void checkExceptionType(TryCatchStatement tryCatch, WasmLocal exceptionVar, List<WasmExpression> target,

core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationVisitor.java

@@ -24,6 +24,7 @@ import org.teavm.ast.ArrayType;
 import org.teavm.ast.BinaryExpr;
 import org.teavm.ast.CastExpr;
 import org.teavm.ast.ConditionalExpr;
+import org.teavm.ast.ConstantExpr;
 import org.teavm.ast.Expr;
 import org.teavm.ast.InstanceOfExpr;
 import org.teavm.ast.InvocationExpr;
@@ -281,20 +282,12 @@ public class WasmGCGenerationVisitor extends BaseWasmGenerationVisitor {
         if (expr.getType() == null) {
             switch (expr.getOperation()) {
                 case EQUALS: {
-                    accept(expr.getFirstOperand());
-                    var first = result;
-                    accept(expr.getSecondOperand());
-                    var second = result;
-                    result = new WasmReferencesEqual(first, second);
+                    isReferenceEq(expr);
                     result.setLocation(expr.getLocation());
                     return;
                 }
                 case NOT_EQUALS:
-                    accept(expr.getFirstOperand());
-                    var first = result;
-                    accept(expr.getSecondOperand());
-                    var second = result;
-                    result = new WasmReferencesEqual(first, second);
+                    isReferenceEq(expr);
                     result = new WasmIntUnary(WasmIntType.INT32, WasmIntUnaryOperation.EQZ, result);
                     result.setLocation(expr.getLocation());
                     return;
@@ -305,6 +298,29 @@ public class WasmGCGenerationVisitor extends BaseWasmGenerationVisitor {
         super.visit(expr);
     }
 
+    private void isReferenceEq(BinaryExpr expr) {
+        if (isNull(expr.getFirstOperand())) {
+            accept(expr.getSecondOperand());
+            result = new WasmIsNull(result);
+        } else if (isNull(expr.getSecondOperand())) {
+            accept(expr.getFirstOperand());
+            result = new WasmIsNull(result);
+        } else {
+            accept(expr.getFirstOperand());
+            var first = result;
+            accept(expr.getSecondOperand());
+            var second = result;
+            result = new WasmReferencesEqual(first, second);
+        }
+    }
+
+    private boolean isNull(Expr expr) {
+        if (!(expr instanceof ConstantExpr)) {
+            return false;
+        }
+        return ((ConstantExpr) expr).getValue() == null;
+    }
+
     @Override
     protected WasmExpression generateVirtualCall(WasmLocal instance, MethodReference method,
             List<WasmExpression> arguments) {

core/src/main/java/org/teavm/backend/wasm/render/WasmBinaryRenderingVisitor.java

@@ -1406,7 +1406,7 @@ class WasmBinaryRenderingVisitor implements WasmExpressionVisitor {
         if (debugLines != null) {
             debugLines.advance(writer.getPosition() + addressOffset);
             while (!methodStack.isEmpty()) {
-                methodStack.removeLast();
+                methodStack.remove(methodStack.size() - 1);
                 debugLines.end();
             }
             debugLines.end();