Fix minor bugs in WASM backend

core/src/main/java/org/teavm/wasm/Example.java

@@ -15,8 +15,6 @@
  */
 package org.teavm.wasm;
 
-import org.teavm.wasm.runtime.WasmRuntime;
-
 public final class Example {
     private Example() {
     }

core/src/main/java/org/teavm/wasm/WasmRuntime.java

@@ -13,7 +13,7 @@
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
  */
-package org.teavm.wasm.runtime;
+package org.teavm.wasm;
 
 import org.teavm.interop.Import;
 
@@ -22,19 +22,19 @@ public final class WasmRuntime {
     }
 
     public static int compare(int a, int b) {
-        return a > b ? 1 : a < b ? -1 : 0;
+        return gt(a, b) ? 1 : lt(a, b) ? -1 : 0;
     }
 
     public static int compare(long a, long b) {
-        return a > b ? 1 : a < b ? -1 : 0;
+        return gt(a, b) ? 1 : lt(a, b) ? -1 : 0;
     }
 
     public static int compare(float a, float b) {
-        return a > b ? 1 : a < b ? -1 : 0;
+        return gt(a, b) ? 1 : lt(a, b) ? -1 : 0;
     }
 
     public static int compare(double a, double b) {
-        return a > b ? 1 : a < b ? -1 : 0;
+        return gt(a, b) ? 1 : lt(a, b) ? -1 : 0;
     }
 
     public static float remainder(float a, float b) {
@@ -45,6 +45,22 @@ public final class WasmRuntime {
         return a - (double) (long) (a / b) * b;
     }
 
+    private static native boolean lt(int a, int b);
+
+    private static native boolean gt(int a, int b);
+
+    private static native boolean lt(long a, long b);
+
+    private static native boolean gt(long a, long b);
+
+    private static native boolean lt(float a, float b);
+
+    private static native boolean gt(float a, float b);
+
+    private static native boolean lt(double a, double b);
+
+    private static native boolean gt(double a, double b);
+
     @Import(name = "print", module = "spectest")
     public static native void print(int a);
 }

core/src/main/java/org/teavm/wasm/WasmTarget.java

@@ -53,6 +53,7 @@ import org.teavm.wasm.generate.WasmClassGenerator;
 import org.teavm.wasm.generate.WasmGenerationContext;
 import org.teavm.wasm.generate.WasmGenerator;
 import org.teavm.wasm.generate.WasmMangling;
+import org.teavm.wasm.intrinsics.WasmRuntimeIntrinsic;
 import org.teavm.wasm.model.WasmFunction;
 import org.teavm.wasm.model.WasmModule;
 import org.teavm.wasm.model.WasmType;
@@ -69,7 +70,6 @@ import org.teavm.wasm.model.expression.WasmLoadInt32;
 import org.teavm.wasm.model.expression.WasmReturn;
 import org.teavm.wasm.model.expression.WasmStoreInt32;
 import org.teavm.wasm.render.WasmRenderer;
-import org.teavm.wasm.runtime.WasmRuntime;
 
 public class WasmTarget implements TeaVMTarget {
     private TeaVMTargetController controller;
@@ -121,6 +121,7 @@ public class WasmTarget implements TeaVMTarget {
         Decompiler decompiler = new Decompiler(classes, controller.getClassLoader(), new HashSet<>(),
                 new HashSet<>());
         WasmGenerationContext context = new WasmGenerationContext(classes);
+        context.addIntrinsic(new WasmRuntimeIntrinsic());
         WasmGenerator generator = new WasmGenerator(decompiler, classes, context, classGenerator);
 
         WasmModule module = new WasmModule();
@@ -133,6 +134,9 @@ public class WasmTarget implements TeaVMTarget {
                         && method.getName().equals("initialize")) {
                     continue;
                 }
+                if (context.getIntrinsic(method.getReference()) != null) {
+                    continue;
+                }
 
                 if (method.hasModifier(ElementModifier.NATIVE)) {
                     if (method.getOwnerName().equals(Structure.class.getName())

core/src/main/java/org/teavm/wasm/generate/WasmGenerationContext.java

@@ -15,7 +15,9 @@
  */
 package org.teavm.wasm.generate;
 
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import org.teavm.interop.Import;
 import org.teavm.model.AnnotationReader;
@@ -27,15 +29,28 @@ import org.teavm.model.FieldReference;
 import org.teavm.model.MethodReader;
 import org.teavm.model.MethodReference;
 import org.teavm.model.ValueType;
+import org.teavm.wasm.intrinsics.WasmIntrinsic;
 
 public class WasmGenerationContext {
     private ClassReaderSource classSource;
     private Map<MethodReference, ImportedMethod> importedMethods = new HashMap<>();
+    private List<WasmIntrinsic> intrinsics = new ArrayList<>();
+    private Map<MethodReference, WasmIntrinsic> intrinsicCache = new HashMap<>();
 
     public WasmGenerationContext(ClassReaderSource classSource) {
         this.classSource = classSource;
     }
 
+    public void addIntrinsic(WasmIntrinsic intrinsic) {
+        intrinsics.add(intrinsic);
+    }
+
+    public WasmIntrinsic getIntrinsic(MethodReference method) {
+        return intrinsicCache.computeIfAbsent(method, key -> intrinsics.stream()
+                .filter(intrinsic -> intrinsic.isApplicable(key))
+                .findFirst().orElse(null));
+    }
+
     public ImportedMethod getImportedMethod(MethodReference reference) {
         return importedMethods.computeIfAbsent(reference, ref -> {
             ClassReader cls = classSource.get(ref.getClassName());

core/src/main/java/org/teavm/wasm/generate/WasmGenerationVisitor.java

@@ -67,6 +67,8 @@ import org.teavm.model.MethodReference;
 import org.teavm.model.ValueType;
 import org.teavm.runtime.Allocator;
 import org.teavm.runtime.RuntimeClass;
+import org.teavm.wasm.intrinsics.WasmIntrinsic;
+import org.teavm.wasm.intrinsics.WasmIntrinsicManager;
 import org.teavm.wasm.model.WasmFunction;
 import org.teavm.wasm.model.WasmLocal;
 import org.teavm.wasm.model.WasmType;
@@ -102,7 +104,7 @@ import org.teavm.wasm.model.expression.WasmStoreFloat64;
 import org.teavm.wasm.model.expression.WasmStoreInt32;
 import org.teavm.wasm.model.expression.WasmStoreInt64;
 import org.teavm.wasm.model.expression.WasmSwitch;
-import org.teavm.wasm.runtime.WasmRuntime;
+import org.teavm.wasm.WasmRuntime;
 
 class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
     private WasmGenerationContext context;
@@ -416,11 +418,11 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
     @Override
     public void visit(ConditionalExpr expr) {
         expr.getCondition().acceptVisitor(this);
-        WasmConditional conditional = new WasmConditional(result);
+        WasmConditional conditional = new WasmConditional(forCondition(result));
         expr.getConsequent().acceptVisitor(this);
         conditional.getThenBlock().getBody().add(result);
         expr.getAlternative().acceptVisitor(this);
-        conditional.getThenBlock().getBody().add(result);
+        conditional.getElseBlock().getBody().add(result);
         result = conditional;
     }
 
@@ -456,7 +458,7 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
     @Override
     public void visit(ConditionalStatement statement) {
         statement.getCondition().acceptVisitor(this);
-        WasmConditional conditional = new WasmConditional(result);
+        WasmConditional conditional = new WasmConditional(forCondition(result));
         for (Statement part : statement.getConsequent()) {
             part.acceptVisitor(this);
             if (result != null) {
@@ -569,6 +571,12 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
             return;
         }
 
+        WasmIntrinsic intrinsic = context.getIntrinsic(expr.getMethod());
+        if (intrinsic != null) {
+            result = intrinsic.apply(expr, intrinsicManager);
+            return;
+        }
+
         if (expr.getType() == InvocationType.STATIC || expr.getType() == InvocationType.SPECIAL) {
             String methodName = WasmMangling.mangleMethod(expr.getMethod());
 
@@ -900,6 +908,35 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
         return expression instanceof WasmInt32Constant && ((WasmInt32Constant) expression).getValue() == 1;
     }
 
+    private boolean isZero(WasmExpression expression) {
+        return expression instanceof WasmInt32Constant && ((WasmInt32Constant) expression).getValue() == 0;
+    }
+
+    private WasmExpression forCondition(WasmExpression expression) {
+        if (expression instanceof WasmIntBinary) {
+            WasmIntBinary binary = (WasmIntBinary) expression;
+            switch (binary.getOperation()) {
+                case EQ:
+                    if (isZero(binary.getFirst())) {
+                        return negate(binary.getSecond());
+                    } else if (isZero(binary.getSecond())) {
+                        return negate(binary.getFirst());
+                    }
+                    break;
+                case NE:
+                    if (isZero(binary.getFirst())) {
+                        return binary.getSecond();
+                    } else if (isZero(binary.getSecond())) {
+                        return binary.getFirst();
+                    }
+                    break;
+                default:
+                    break;
+            }
+        }
+        return expression;
+    }
+
     private WasmIntBinaryOperation negate(WasmIntBinaryOperation op) {
         switch (op) {
             case EQ:
@@ -945,4 +982,12 @@ class WasmGenerationVisitor implements StatementVisitor, ExprVisitor {
                 return null;
         }
     }
+
+    private WasmIntrinsicManager intrinsicManager = new WasmIntrinsicManager() {
+        @Override
+        public WasmExpression generate(Expr expr) {
+            expr.acceptVisitor(WasmGenerationVisitor.this);
+            return result;
+        }
+    };
 }

core/src/main/java/org/teavm/wasm/intrinsics/WasmIntrinsic.java

@@ -0,0 +1,26 @@
+/*
+ *  Copyright 2016 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.wasm.intrinsics;
+
+import org.teavm.ast.InvocationExpr;
+import org.teavm.model.MethodReference;
+import org.teavm.wasm.model.expression.WasmExpression;
+
+public interface WasmIntrinsic {
+    boolean isApplicable(MethodReference methodReference);
+
+    WasmExpression apply(InvocationExpr invocation, WasmIntrinsicManager manager);
+}

core/src/main/java/org/teavm/wasm/intrinsics/WasmIntrinsicManager.java

@@ -0,0 +1,23 @@
+/*
+ *  Copyright 2016 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.wasm.intrinsics;
+
+import org.teavm.ast.Expr;
+import org.teavm.wasm.model.expression.WasmExpression;
+
+public interface WasmIntrinsicManager {
+    WasmExpression generate(Expr expr);
+}

core/src/main/java/org/teavm/wasm/intrinsics/WasmRuntimeIntrinsic.java

@@ -0,0 +1,73 @@
+/*
+ *  Copyright 2016 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.wasm.intrinsics;
+
+import org.teavm.ast.InvocationExpr;
+import org.teavm.model.MethodReference;
+import org.teavm.wasm.WasmRuntime;
+import org.teavm.wasm.generate.WasmGeneratorUtil;
+import org.teavm.wasm.model.WasmType;
+import org.teavm.wasm.model.expression.WasmExpression;
+import org.teavm.wasm.model.expression.WasmFloatBinary;
+import org.teavm.wasm.model.expression.WasmFloatBinaryOperation;
+import org.teavm.wasm.model.expression.WasmFloatType;
+import org.teavm.wasm.model.expression.WasmIntBinary;
+import org.teavm.wasm.model.expression.WasmIntBinaryOperation;
+import org.teavm.wasm.model.expression.WasmIntType;
+
+public class WasmRuntimeIntrinsic implements WasmIntrinsic {
+    @Override
+    public boolean isApplicable(MethodReference methodReference) {
+        return methodReference.getClassName().equals(WasmRuntime.class.getName()) &&
+                (methodReference.getName().equals("lt") || methodReference.getName().equals("gt"));
+    }
+
+    @Override
+    public WasmExpression apply(InvocationExpr invocation, WasmIntrinsicManager manager) {
+        WasmType type = WasmGeneratorUtil.mapType(invocation.getMethod().parameterType(0));
+
+        WasmExpression first = manager.generate(invocation.getArguments().get(0));
+        WasmExpression second = manager.generate(invocation.getArguments().get(1));
+
+        WasmIntBinaryOperation intOp;
+        WasmFloatBinaryOperation floatOp;
+        switch (invocation.getMethod().getName()) {
+            case "lt":
+                intOp = WasmIntBinaryOperation.LT_SIGNED;
+                floatOp = WasmFloatBinaryOperation.LT;
+                break;
+            case "gt":
+                intOp = WasmIntBinaryOperation.GT_SIGNED;
+                floatOp = WasmFloatBinaryOperation.GT;
+                break;
+            default:
+                throw new IllegalArgumentException(invocation.getMethod().getName());
+        }
+
+        switch (type) {
+            case INT32:
+                return new WasmIntBinary(WasmIntType.INT32, intOp, first, second);
+            case INT64:
+                return new WasmIntBinary(WasmIntType.INT64, intOp, first, second);
+            case FLOAT32:
+                return new WasmFloatBinary(WasmFloatType.FLOAT32, floatOp, first, second);
+            case FLOAT64:
+                return new WasmFloatBinary(WasmFloatType.FLOAT64, floatOp, first, second);
+        }
+
+        return null;
+    }
+}

core/src/main/java/org/teavm/wasm/render/WasmRenderingVisitor.java

@@ -180,7 +180,7 @@ class WasmRenderingVisitor implements WasmExpressionVisitor {
         renderBlock(expression.getThenBlock(), "then");
 
         lf();
-        renderBlock(expression.getThenBlock(), "else");
+        renderBlock(expression.getElseBlock(), "else");
 
         close();
     }