[WASM] Allow declaring native wasm arrays.

Arrays of native types will be considered as native wasm arrays. PiperOrigin-RevId: 571345388
google · Oct 6, 2023 · 49bac39 · 49bac39
1 parent 5023572
commit 49bac39
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Showing 6 changed files with 66 additions and 9 deletions.
diff --git a/transpiler/java/com/google/j2cl/transpiler/ast/ArrayTypeDescriptor.java b/transpiler/java/com/google/j2cl/transpiler/ast/ArrayTypeDescriptor.java
@@ -75,7 +75,22 @@ public boolean isUntypedArray() {
    * Returns true for arrays where raw wasm array representation is enough. These arrays are located
    * in {@see javaemul.internal.WasmArrays}.
    */
-  public abstract boolean isNativeWasmArray();
+  public abstract boolean isMarkedAsNativeWasmArray();
+
+  @Override
+  public boolean isNativeWasmArray() {
+    if (isMarkedAsNativeWasmArray()) {
+      return true;
+    }
+
+    if (getComponentTypeDescriptor().toRawTypeDescriptor() instanceof DeclaredTypeDescriptor) {
+      DeclaredTypeDescriptor componentTypeDescriptor =
+          (DeclaredTypeDescriptor) getComponentTypeDescriptor().toRawTypeDescriptor();
+      return componentTypeDescriptor.getTypeDeclaration().getWasmInfo() != null;
+    }
+
+    return false;
+  }
 
   @Override
   public abstract boolean isNullable();
@@ -228,7 +243,7 @@ public static Builder newBuilder() {
     return new AutoValue_ArrayTypeDescriptor.Builder()
         // Default values.
         .setNullable(true)
-        .setNativeWasmArray(false);
+        .setMarkedAsNativeWasmArray(false);
   }
 
   /** Builder for an ArrayTypeDescriptor. */
@@ -242,7 +257,7 @@ public static Builder from(ArrayTypeDescriptor arrayTypeDescriptor) {
 
     public abstract Builder setNullable(boolean isNullable);
 
-    public abstract Builder setNativeWasmArray(boolean wasmNative);
+    public abstract Builder setMarkedAsNativeWasmArray(boolean wasmNative);
 
     abstract ArrayTypeDescriptor autoBuild();
 

diff --git a/transpiler/java/com/google/j2cl/transpiler/ast/TypeDescriptor.java b/transpiler/java/com/google/j2cl/transpiler/ast/TypeDescriptor.java
@@ -114,6 +114,11 @@ public boolean isAnnotatedWithFunctionalInterface() {
     return false;
   }
 
+  /** Returns whether the described type is a wasm native array. */
+  public boolean isNativeWasmArray() {
+    return false;
+  }
+
   /**
    * Returns the mangled name of a type.
    *

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/wasm/WasmGenerationEnvironment.java b/transpiler/java/com/google/j2cl/transpiler/backend/wasm/WasmGenerationEnvironment.java
@@ -146,7 +146,10 @@ String getWasmTypeName(TypeDescriptor typeDescriptor) {
     if (typeDescriptor.isArray()) {
       ArrayTypeDescriptor arrayTypeDescriptor = (ArrayTypeDescriptor) typeDescriptor;
       if (arrayTypeDescriptor.isNativeWasmArray()) {
-        return getWasmTypeName(arrayTypeDescriptor.getComponentTypeDescriptor()) + ".array";
+        String wasmTypeName = getWasmTypeName(arrayTypeDescriptor.getComponentTypeDescriptor());
+        // Make sure the resulting type name always has $ prefix.
+        String prefix = wasmTypeName.startsWith("$") ? "" : "$";
+        return format("%s%s.array", prefix, wasmTypeName);
       }
       return getWasmTypeName(TypeDescriptors.getWasmArrayType(arrayTypeDescriptor));
     }
@@ -172,9 +175,6 @@ private static String getTypeSignature(TypeDescriptor typeDescriptor) {
   }
 
   public String getWasmEmptyArrayGlobalName(ArrayTypeDescriptor arrayTypeDescriptor) {
-    checkArgument(
-        arrayTypeDescriptor.isPrimitiveArray()
-            || TypeDescriptors.isJavaLangObject(arrayTypeDescriptor.getComponentTypeDescriptor()));
     return "$__emptyArray_" + getWasmTypeName(arrayTypeDescriptor);
   }
   /** Returns the name of the global that stores the itable for a Java type. */

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/wasm/WasmOutputsGenerator.java b/transpiler/java/com/google/j2cl/transpiler/backend/wasm/WasmOutputsGenerator.java
@@ -824,11 +824,23 @@ private void emitWasmStruct(
 
   private List<ArrayTypeDescriptor> collectUsedNativeArrayTypes(Library library) {
     Set<ArrayTypeDescriptor> usedArrayTypes = new LinkedHashSet<>();
+    // Collect native arrays from fields and variables; this covers all scenarios.
     library.accept(
+        // TODO(b/303659726): Generalize a type visitor that could be used here and other places
+        // like in ImportGatherer. Or consider emitting the one dimensional array type for all
+        // native types.
         new AbstractVisitor() {
           @Override
           public void exitField(Field field) {
-            TypeDescriptor typeDescriptor = field.getDescriptor().getTypeDescriptor();
+            collectIfArrayType(field.getDescriptor().getTypeDescriptor());
+          }
+
+          @Override
+          public void exitVariable(Variable variable) {
+            collectIfArrayType(variable.getTypeDescriptor());
+          }
+
+          private void collectIfArrayType(TypeDescriptor typeDescriptor) {
             if (!typeDescriptor.isArray()) {
               return;
             }

diff --git a/transpiler/java/com/google/j2cl/transpiler/passes/ImplementArraysAsClasses.java b/transpiler/java/com/google/j2cl/transpiler/passes/ImplementArraysAsClasses.java
@@ -302,7 +302,7 @@ private static Variable markVariableTypeDescriptorAsNative(Variable original) {
   }
 
   private static ArrayTypeDescriptor markArrayTypeDescriptorAsNative(ArrayTypeDescriptor original) {
-    return ArrayTypeDescriptor.Builder.from(original).setNativeWasmArray(true).build();
+    return ArrayTypeDescriptor.Builder.from(original).setMarkedAsNativeWasmArray(true).build();
   }
 
   private static TypeDescriptor maybeMarkTypeDescriptorAsNative(TypeDescriptor original) {

diff --git a/transpiler/javatests/com/google/j2cl/integration/java/wasm/super-wasm/Main.java b/transpiler/javatests/com/google/j2cl/integration/java/wasm/super-wasm/Main.java
@@ -27,13 +27,15 @@
  * <p>This test will be removed when all Wasm features are implemented and all integration tests are
  * enabled for Wasm.
  */
+@SuppressWarnings("unusable-by-js")
 public class Main {
 
   public static void main(String... args) throws Exception {
     testWasmAnnotation();
     testClassLiterals();
     testArrayInstanceOf();
     testArrayGetClass();
+    testNativeArrays();
   }
 
   private static void testWasmAnnotation() {
@@ -139,4 +141,27 @@ private static void testArrayGetClass() {
     assertEquals(Object[].class, objectArray.getClass());
     assertEquals(Object.class, objectArray.getClass().getComponentType());
   }
+
+  @Wasm("i31")
+  interface I31Ref {}
+
+  @Wasm("ref.i31")
+  private static native I31Ref toI31Ref(int value);
+
+  @Wasm("i31.get_s")
+  private static native int i31GetS(I31Ref value);
+
+  private static void testNativeArrays() {
+    I31Ref[] i31Refs = new I31Ref[10];
+
+    I31Ref two = toI31Ref(2);
+    i31Refs[1] = two;
+    assertTrue(i31GetS(i31Refs[1]) == 2);
+    for (int i = 0; i < i31Refs.length; i++) {
+      i31Refs[i] = toI31Ref(i);
+    }
+    for (int i = 0; i < i31Refs.length; i++) {
+      assertTrue(i31GetS(i31Refs[i]) == i);
+    }
+  }
 }