[wasm][anyref] Introduce anyfunc locals

R=titzer@chromium.org

Bug: v8:7581
Change-Id: I153b09ac1676c75590f37c4b7d1f8659c37bbe96
Reviewed-on: https://chromium-review.googlesource.com/c/1421837
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59029}

src/wasm/function-body-decoder-impl.h

@@ -762,6 +762,15 @@ class WasmDecoder : public Decoder {
           }
           decoder->error(decoder->pc() - 1, "invalid local type");
           return false;
+        case kLocalAnyFunc:
+          if (enabled.anyref) {
+            type = kWasmAnyFunc;
+            break;
+          }
+          decoder->error(decoder->pc() - 1,
+                         "local type 'anyfunc' is not enabled with "
+                         "--experimental-wasm-anyref");
+          return false;
         case kLocalExceptRef:
           if (enabled.eh) {
             type = kWasmExceptRef;

src/wasm/graph-builder-interface.cc

@@ -644,6 +644,7 @@ class WasmGraphBuildingInterface {
       case kWasmS128:
         return builder_->S128Zero();
       case kWasmAnyRef:
+      case kWasmAnyFunc:
       case kWasmExceptRef:
         return builder_->RefNull();
       default:

test/mjsunit/wasm/anyfunc.js

@@ -41,3 +41,85 @@ load("test/mjsunit/wasm/wasm-module-builder.js");
 
   main(main);
 })();
+
+(function testPassAnyRefWithGCWithLocals() {
+  print(arguments.callee.name);
+  const builder = new WasmModuleBuilder();
+  const ref_sig = builder.addType(kSig_v_a);
+  const void_sig = builder.addType(kSig_v_v);
+  const imp_index = builder.addImport("q", "func", ref_sig);
+  const gc_index = builder.addImport("q", "gc", void_sig);
+  // First call the gc, then check if the object still exists.
+  builder.addFunction('main', ref_sig)
+      .addLocals({anyfunc_count: 10})
+      .addBody([
+        kExprGetLocal, 0, kExprSetLocal, 1,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 2,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 3,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 4,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 5,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 6,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 7,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 8,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 9,             // Set local
+        kExprGetLocal, 0, kExprSetLocal, 10,            // Set local
+        kExprCallFunction, gc_index,                    // call gc
+        kExprGetLocal, 9, kExprCallFunction, imp_index  // call import
+      ])
+      .exportFunc();
+
+  const main =
+      builder.instantiate({q: {func: checkFunction, gc: gc}}).exports.main;
+
+  function checkFunction(value) {
+    assertSame(main, value);
+  }
+
+  main(main);
+})();
+
+(function testPassAnyRefWithGC() {
+  print(arguments.callee.name);
+  const builder = new WasmModuleBuilder();
+  const ref_sig = builder.addType(kSig_v_a);
+  const void_sig = builder.addType(kSig_v_v);
+  const imp_index = builder.addImport("q", "func", ref_sig);
+  const gc_index = builder.addImport("q", "gc", void_sig);
+  // First call the gc, then check if the object still exists.
+  builder.addFunction('main', ref_sig)
+      .addBody([
+        kExprCallFunction, gc_index,                    // call gc
+        kExprGetLocal, 0, kExprCallFunction, imp_index  // call import
+      ])
+      .exportFunc();
+
+  function checkFunction(value) {
+    assertSame(main, value);
+  }
+
+  const main = builder.instantiate({q: {func: checkFunction, gc: gc}}).exports.main;
+
+  main(main);
+})();
+
+(function testPassAnyRefWithGCInWrapper() {
+  print(arguments.callee.name);
+  const builder = new WasmModuleBuilder();
+  const kSig_a_iai = makeSig([kWasmI32, kWasmAnyFunc, kWasmI32], [kWasmAnyFunc]);
+  const sig_index = builder.addType(kSig_a_iai);
+  builder.addFunction('main', sig_index)
+      .addBody([kExprGetLocal, 1])
+      .exportFunc();
+
+  const main = builder.instantiate().exports.main;
+
+  const triggerGCParam = {
+    valueOf: () => {
+      gc();
+      return 17;
+    }
+  };
+
+  const result = main(triggerGCParam, main, triggerGCParam);
+  assertSame(main, result);
+})();

test/mjsunit/wasm/wasm-module-builder.js

@@ -617,6 +617,9 @@ class WasmModuleBuilder {
             if (l.anyref_count > 0) {
               local_decls.push({count: l.anyref_count, type: kWasmAnyRef});
             }
+            if (l.anyfunc_count > 0) {
+              local_decls.push({count: l.anyfunc_count, type: kWasmAnyFunc});
+            }
             if (l.except_count > 0) {
               local_decls.push({count: l.except_count, type: kWasmExceptRef});
             }