[wasm][test] Represent constant expressions with bytes

Maintaining an AST class just for testing constant exressions does not
seem justified. This CL changes constant expressions in mjsunit tests
to be represented with bytes, like regular expressions.

Change-Id: If5ec5f4d863176952442b1a7e2fec8a61e385971
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3714237Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81266}

test/mjsunit/regress/wasm/regress-10702.js

@@ -5,7 +5,7 @@
 d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
 
 const builder = new WasmModuleBuilder();
-builder.addGlobal(kWasmI32, true, WasmInitExpr.I32Const(35));
+builder.addGlobal(kWasmI32, true, wasmI32Const(35));
 builder.addType(makeSig([], [kWasmI32]));
 builder.addType(makeSig([kWasmI32, kWasmI32], [kWasmI32]));
 // Generate function 1 (out of 3).

test/mjsunit/regress/wasm/regress-1187831.js

@@ -11,7 +11,7 @@ builder.addMemory(16, 32, false, true);
 builder.addType(makeSig([kWasmI32, kWasmI32, kWasmI32], [kWasmI32]));
 builder.addType(makeSig([], []));
 builder.setTableBounds(1, 1);
-builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0]);
+builder.addActiveElementSegment(0, wasmI32Const(0), [0]);
 // Generate function 1 (out of 1).
 builder.addFunction(undefined, 0 /* sig */)
   .addBodyWithEnd([

test/mjsunit/regress/wasm/regress-1239954.js

@@ -16,9 +16,9 @@ let other = builder.addFunction("other", sig_index).addBody([]);
 
 let table = builder.addTable(kWasmAnyFunc, 1, 1);
 builder.addActiveElementSegment(
-    0,                         // table
-    WasmInitExpr.I32Const(0),  // offset
-    [1]);                      // values
+    0,                // table
+    wasmI32Const(0),  // offset
+    [1]);             // values
 
 main.addBody([
     kExprI64Const, 0x33,

test/mjsunit/regress/wasm/regress-1247659.js

@@ -6,7 +6,7 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
 
 const builder = new WasmModuleBuilder();
 builder.addMemory(16, 17);
-builder.addGlobal(kWasmI32, 1, WasmInitExpr.I32Const(10));
+builder.addGlobal(kWasmI32, 1, wasmI32Const(10));
 // Generate function 1 (out of 3).
 builder.addFunction('load', kSig_i_v)
     .addBody([

test/mjsunit/regress/wasm/regress-12624.js

@@ -17,7 +17,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
 var builder = new WasmModuleBuilder();
 
-builder.addGlobal(kWasmI32, true, WasmInitExpr.I32Const(1));
+builder.addGlobal(kWasmI32, true, wasmI32Const(1));
 
 builder.addFunction("main", kSig_i_i)
   .addBody([

test/mjsunit/regress/wasm/regress-1299183.js

@@ -21,10 +21,10 @@ builder.addTable(kWasmFuncRef, 4, 5, undefined)
 builder.addTable(kWasmFuncRef, 15, 25, undefined)
 builder.addTable(kWasmFuncRef, 1, 1, undefined)
 builder.addTable(kWasmFuncRef, 16, 17, undefined)
-builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3)], kWasmFuncRef);
-builder.addActiveElementSegment(1, WasmInitExpr.I32Const(0), [WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3), WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3), WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3), WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2)], kWasmFuncRef);
-builder.addActiveElementSegment(2, WasmInitExpr.I32Const(0), [WasmInitExpr.RefFunc(0)], kWasmFuncRef);
-builder.addActiveElementSegment(3, WasmInitExpr.I32Const(0), [WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3), WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3), WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3), WasmInitExpr.RefFunc(0), WasmInitExpr.RefFunc(1), WasmInitExpr.RefFunc(2), WasmInitExpr.RefFunc(3)], kWasmFuncRef);
+builder.addActiveElementSegment(0, wasmI32Const(0), [[kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3]], kWasmFuncRef);
+builder.addActiveElementSegment(1, wasmI32Const(0), [[kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3], [kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3], [kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3], [kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2]], kWasmFuncRef);
+builder.addActiveElementSegment(2, wasmI32Const(0), [[kExprRefFunc, 0]], kWasmFuncRef);
+builder.addActiveElementSegment(3, wasmI32Const(0), [[kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3], [kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3], [kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3], [kExprRefFunc, 0], [kExprRefFunc, 1], [kExprRefFunc, 2], [kExprRefFunc, 3]], kWasmFuncRef);
 builder.addTag(makeSig([], []));
 // Generate function 1 (out of 4).
 builder.addFunction(undefined, 1 /* sig */)

test/mjsunit/regress/wasm/regress-739768.js

@@ -24,7 +24,7 @@ let builder1 = new WasmModuleBuilder();
 builder1.setName('module_1');
 builder1.addFunction('main', kSig_i_v).addBody([kExprUnreachable]);
 builder1.addImportedTable('z', 'table');
-builder1.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0]);
+builder1.addActiveElementSegment(0, wasmI32Const(0), [0]);
 let module1 = new WebAssembly.Module(builder1.toBuffer());
 let instance1 =
     new WebAssembly.Instance(module1, {z: {table: instance0.exports.table}});

test/mjsunit/regress/wasm/regress-803788.js

@@ -11,7 +11,7 @@ let q_table = builder.addImportedTable("q", "table")
 let q_base = builder.addImportedGlobal("q", "base", kWasmI32);
 let q_fun = builder.addImport("q", "fun", kSig_v_v);
 builder.addType(kSig_i_ii);
-builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(q_base), [q_fun]);
+builder.addActiveElementSegment(0, [kExprGlobalGet, q_base], [q_fun]);
 let module = new WebAssembly.Module(builder.toBuffer());
 let table = new WebAssembly.Table({
   element: "anyfunc",

test/mjsunit/regress/wasm/regress-817380.js

@@ -19,7 +19,6 @@ const builder2 = new WasmModuleBuilder();
 const mul_import = builder2.addImport('q', 'wasm_mul', kSig_i_ii);
 builder2.addImportedTable('q', 'table');
 const glob_import = builder2.addImportedGlobal('q', 'glob', kWasmI32);
-builder2.addActiveElementSegment(0, WasmInitExpr.GlobalGet(glob_import),
-                                 [mul_import]);
+builder2.addActiveElementSegment(0, [kExprGlobalGet, glob_import], [mul_import]);
 builder2.instantiate(
     {q: {glob: 0, js_div: i => i, wasm_mul: mul, table: table}});

test/mjsunit/regress/wasm/regress-834619.js

@@ -33,7 +33,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
         kExprCallIndirect, 0, kTableZero
       ])
       .exportFunc();
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0, 1, 1, 0]);
+    builder.addActiveElementSegment(0, wasmI32Const(0), [0, 1, 1, 0]);
 
     return builder.instantiate({q: {f2: i1.exports.f2, f1: i1.exports.f1}});
   })();

test/mjsunit/wasm/array-init-from-segment.js

@@ -14,8 +14,8 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let array_type_index = builder.addArray(struct_type, true);
 
   function makeStruct(element) {
-    return WasmInitExpr.StructNew(
-      struct_type_index, [WasmInitExpr.I32Const(element)]);
+    return [...wasmI32Const(element),
+            kGCPrefix, kExprStructNew, struct_type_index];
   }
 
   builder.addTable(kWasmAnyRef, 10, 10);
@@ -24,11 +24,11 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let passive_segment = builder.addPassiveElementSegment(
     [makeStruct(elems[0]), makeStruct(elems[1]),
-     WasmInitExpr.RefNull(struct_type_index)],
+     [kExprRefNull, struct_type_index]],
     struct_type);
 
   let active_segment = builder.addActiveElementSegment(
-      0, WasmInitExpr.I32Const(0), [makeStruct(elems[2]), makeStruct(elems[3])],
+      0, wasmI32Const(0), [makeStruct(elems[2]), makeStruct(elems[3])],
       struct_type);
 
   function generator(name, segment) {
@@ -87,8 +87,8 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let array_type = wasmOptRefType(array_type_index);
 
   function makeStruct(element) {
-    return WasmInitExpr.StructNew(
-      struct_type_index, [WasmInitExpr.I32Const(element)]);
+    return [...wasmI32Const(element),
+            kGCPrefix, kExprStructNew, struct_type_index];
   }
 
   builder.addTable(kWasmAnyRef, 10, 10);
@@ -98,22 +98,21 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let passive_segment = builder.addPassiveElementSegment(
     [makeStruct(elems[0]), makeStruct(elems[1]),
-     WasmInitExpr.RefNull(struct_type_index)],
+     [kExprRefNull, struct_type_index]],
     struct_type);
 
   let active_segment = builder.addActiveElementSegment(
-      0, WasmInitExpr.I32Const(0), [makeStruct(elems[2]), makeStruct(elems[3])],
+      0, wasmI32Const(0), [makeStruct(elems[2]), makeStruct(elems[3])],
       struct_type);
 
   let array_segment = builder.addPassiveElementSegment(
-    [WasmInitExpr.ArrayInitFromElemStatic(
-       array_type_index, passive_segment,
-       [WasmInitExpr.I32Const(0), WasmInitExpr.I32Const(3)]),
-     WasmInitExpr.ArrayInitFromElemStatic(
-       array_type_index, active_segment,
-       [WasmInitExpr.I32Const(0), WasmInitExpr.I32Const(0)])],
-    array_type
-  );
+    [[...wasmI32Const(0), ...wasmI32Const(3),
+      kGCPrefix, kExprArrayInitFromElemStatic,
+      array_type_index, passive_segment],
+     [...wasmI32Const(0), ...wasmI32Const(0),
+      kGCPrefix, kExprArrayInitFromElemStatic,
+      array_type_index, active_segment]],
+    array_type);
 
   builder.addFunction("init", kSig_v_v)
     .addBody([kExprI32Const, 0, kExprI32Const, 0, kExprI32Const, 2,
@@ -168,7 +167,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let array_type_index = builder.addArray(struct_type, true);
 
   let passive_segment = builder.addPassiveElementSegment([
-    WasmInitExpr.RefNull(array_type_index)],
+    [kExprRefNull, array_type_index]],
     wasmOptRefType(array_type_index));
 
   builder.addFunction("mistyped", makeSig([kWasmI32, kWasmI32], [kWasmI32]))
@@ -196,16 +195,14 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let array_type_index = builder.addArray(struct_type, true);
 
   let passive_segment = builder.addPassiveElementSegment([
-    WasmInitExpr.RefNull(struct_type_index)],
+    [kExprRefNull, struct_type_index]],
     struct_type_index);
 
-  builder.addGlobal(wasmOptRefType(array_type_index), false,
-    WasmInitExpr.ArrayInitFromElemStatic(
-        array_type_index, passive_segment,
-        [WasmInitExpr.I32Const(0),  // offset
-         WasmInitExpr.I32Const(1)   // length
-        ])
-  );
+  builder.addGlobal(
+    wasmOptRefType(array_type_index), false,
+    [...wasmI32Const(0), ...wasmI32Const(1),
+     kGCPrefix, kExprArrayInitFromElemStatic,
+     array_type_index, passive_segment]);
 
   assertThrows(() => builder.instantiate(), WebAssembly.CompileError,
                /invalid element segment index/);
@@ -220,8 +217,8 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let array_type = wasmOptRefType(array_type_index);
 
   function makeStruct(element) {
-    return WasmInitExpr.StructNew(
-      struct_type_index, [WasmInitExpr.I32Const(element)]);
+    return [...wasmI32Const(element),
+            kGCPrefix, kExprStructNew, struct_type_index];
   }
 
   builder.addTable(kWasmAnyRef, 10, 10);
@@ -231,13 +228,13 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let passive_segment = builder.addPassiveElementSegment(
     [makeStruct(elems[0]), makeStruct(elems[1]),
-     WasmInitExpr.RefNull(struct_type_index)],
+     [kExprRefNull, struct_type_index]],
     struct_type);
 
   let array_segment = builder.addPassiveElementSegment(
-    [WasmInitExpr.ArrayInitFromElemStatic(
-       array_type_index, passive_segment,
-       [WasmInitExpr.I32Const(0), WasmInitExpr.I32Const(1 << 30)])],
+    [[...wasmI32Const(0), ...wasmI32Const(1 << 30),
+      kGCPrefix, kExprArrayInitFromElemStatic,
+      array_type_index, passive_segment]],
     array_type
   );
 
@@ -259,8 +256,8 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let array_type = wasmOptRefType(array_type_index);
 
   function makeStruct(element) {
-    return WasmInitExpr.StructNew(
-      struct_type_index, [WasmInitExpr.I32Const(element)]);
+    return [...wasmI32Const(element),
+            kGCPrefix, kExprStructNew, struct_type_index];
   }
 
   builder.addTable(kWasmAnyRef, 10, 10);
@@ -270,13 +267,13 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let passive_segment = builder.addPassiveElementSegment(
     [makeStruct(elems[0]), makeStruct(elems[1]),
-     WasmInitExpr.RefNull(struct_type_index)],
+     [kExprRefNull, struct_type_index]],
     struct_type);
 
   let array_segment = builder.addPassiveElementSegment(
-    [WasmInitExpr.ArrayInitFromElemStatic(
-       array_type_index, passive_segment,
-       [WasmInitExpr.I32Const(0), WasmInitExpr.I32Const(10)])],
+    [[...wasmI32Const(0), ...wasmI32Const(10),
+      kGCPrefix, kExprArrayInitFromElemStatic,
+      array_type_index, passive_segment]],
     array_type
   );
 
@@ -298,8 +295,8 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let array_type = wasmOptRefType(array_type_index);
 
   function makeStruct(element) {
-    return WasmInitExpr.StructNew(
-      struct_type_index, [WasmInitExpr.I32Const(element)]);
+    return [...wasmI32Const(element),
+            kGCPrefix, kExprStructNew, struct_type_index];
   }
 
   builder.addTable(kWasmAnyRef, 10, 10);
@@ -308,15 +305,15 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let elems = [10, -10];
 
   let active_segment = builder.addActiveElementSegment(
-    table, WasmInitExpr.I32Const(0),
+    table, wasmI32Const(0),
     [makeStruct(elems[0]), makeStruct(elems[1]),
-     WasmInitExpr.RefNull(struct_type_index)],
+     [kExprRefNull, struct_type_index]],
     struct_type);
 
   let array_segment = builder.addPassiveElementSegment(
-    [WasmInitExpr.ArrayInitFromElemStatic(
-       array_type_index, active_segment,
-       [WasmInitExpr.I32Const(0), WasmInitExpr.I32Const(3)])],
+    [[...wasmI32Const(0), ...wasmI32Const(3),
+      kGCPrefix, kExprArrayInitFromElemStatic,
+      array_type_index, active_segment]],
     array_type
   );
 

test/mjsunit/wasm/bulk-memory.js

@@ -158,7 +158,7 @@ function getMemoryFill(mem) {
 (function TestElemDropActive() {
   const builder = new WasmModuleBuilder();
   builder.setTableBounds(5, 5);
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0, 0, 0]);
+  builder.addActiveElementSegment(0, wasmI32Const(0), [0, 0, 0]);
   builder.addFunction('drop', kSig_v_v)
       .addBody([
         kNumericPrefix, kExprElemDrop,
@@ -204,7 +204,7 @@ function getMemoryFill(mem) {
   const tableIndex = 0;
   builder.addActiveElementSegment(
       tableIndex,
-      WasmInitExpr.I32Const(0),
+      wasmI32Const(0),
       [f.index, f.index]);
   builder.addDataSegment(0, [42]);
 

test/mjsunit/wasm/compiled-module-serialization.js

@@ -220,7 +220,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
       .exportAs("main");
 
     builder.setTableBounds(kTableSize, kTableSize);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [f1.index]);
+    builder.addActiveElementSegment(0, wasmI32Const(0), [f1.index]);
     builder.addExportOfKind("table", kExternalTable, 0);
 
     return new WebAssembly.Module(builder.toBuffer());
@@ -241,7 +241,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     .exportAs("main");
 
   builder.addImportedTable("z", "table", kTableSize, kTableSize);
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(1), [f2.index]);
+  builder.addActiveElementSegment(0, wasmI32Const(1), [f2.index]);
   var m2_bytes = builder.toBuffer();
   var m2 = new WebAssembly.Module(m2_bytes);
 

test/mjsunit/wasm/element-segments-with-reftypes.js

@@ -17,23 +17,17 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
     kExprLocalGet, 0, kExprI32Const, 1, kExprI32Add
   ]);
   let global0 =
-      builder.addGlobal(kWasmFuncRef, false, WasmInitExpr.RefFunc(f0.index));
+      builder.addGlobal(kWasmFuncRef, false, [kExprRefFunc, f0.index]);
   let global1 =
-      builder.addGlobal(kWasmFuncRef, false, WasmInitExpr.RefFunc(f1.index));
+      builder.addGlobal(kWasmFuncRef, false, [kExprRefFunc, f1.index]);
   // At instantiation, table[0] = global0, table[1] = global1.
   builder.addActiveElementSegment(
-      table.index, WasmInitExpr.I32Const(0),
-      [
-        WasmInitExpr.GlobalGet(global0.index),
-        WasmInitExpr.GlobalGet(global1.index)
-      ],
+      table.index, wasmI32Const(0),
+      [[kExprGlobalGet, global0.index], [kExprGlobalGet, global1.index]],
       kWasmFuncRef);
 
   let passive = builder.addPassiveElementSegment(
-      [
-        WasmInitExpr.GlobalGet(global0.index),
-        WasmInitExpr.GlobalGet(global1.index)
-      ],
+      [[kExprGlobalGet, global0.index], [kExprGlobalGet, global1.index]],
       kWasmFuncRef);
 
   // table[2] = global0, table[3] = global1.
@@ -42,8 +36,7 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
         kExprI32Const, 2,  // table index
         kExprI32Const, 0,  // element index
         kExprI32Const, 2,  // length
-        kNumericPrefix, kExprTableInit, passive, table.index
-      ])
+        kNumericPrefix, kExprTableInit, passive, table.index])
       .exportFunc();
 
   let instance = builder.instantiate({});
@@ -68,16 +61,16 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
   ]);
 
   let table =
-      builder.addTable(wasmRefType(sig), 10, 10, WasmInitExpr.RefFunc(f0.index))
+      builder.addTable(wasmRefType(sig), 10, 10, [kExprRefFunc, f0.index])
           .exportAs('table');
 
   builder.addActiveElementSegment(
-      table.index, WasmInitExpr.I32Const(0),
-      [WasmInitExpr.RefFunc(f0.index), WasmInitExpr.RefFunc(f1.index)],
+      table.index, wasmI32Const(0),
+      [[kExprRefFunc, f0.index], [kExprRefFunc, f1.index]],
       wasmRefType(sig));
 
   let passive = builder.addPassiveElementSegment(
-      [WasmInitExpr.RefFunc(f0.index), WasmInitExpr.RefFunc(f1.index)],
+      [[kExprRefFunc, f0.index], [kExprRefFunc, f1.index]],
       wasmRefType(sig));
 
   builder.addFunction('init', kSig_v_v)
@@ -106,8 +99,8 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
   let global = builder.addImportedGlobal("m", "g", kWasmFuncRef, true);
   let table = builder.addTable(kWasmFuncRef, 10, 10);
   builder.addActiveElementSegment(
-      table.index, WasmInitExpr.I32Const(0),
-      [WasmInitExpr.GlobalGet(global.index)], kWasmFuncRef);
+      table.index, wasmI32Const(0),
+      [[kExprGlobalGet, global]], kWasmFuncRef);
   builder.addExportOfKind("table", kExternalTable, table.index);
 
   assertThrows(

test/mjsunit/wasm/export-mutable-global.js

@@ -7,20 +7,20 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 (function exportImmutableGlobal() {
   var builder = new WasmModuleBuilder();
   let globals = [
-    [kWasmI32, 'i32', WasmInitExpr.I32Const(4711)],
-    [kWasmF32, 'f32', WasmInitExpr.F32Const(Math.fround(3.14))],
-    [kWasmF64, 'f64', WasmInitExpr.F64Const(1 / 7)]
+    [kWasmI32, 'i32', 4711, wasmI32Const(4711)],
+    [kWasmF32, 'f32', Math.fround(3.14), wasmF32Const(Math.fround(3.14))],
+    [kWasmF64, 'f64', 1/7, wasmF64Const(1 / 7)]
   ];
-  for (let [type, name, value] of globals) {
-    builder.addGlobal(type, false, value).exportAs(name);
+  for (let [type, name, value, bytes] of globals) {
+    builder.addGlobal(type, false, bytes).exportAs(name);
   }
   var instance = builder.instantiate();
 
-  for (let [type, name, value] of globals) {
+  for (let [type, name, value, bytes] of globals) {
     let obj = instance.exports[name];
     assertEquals("object", typeof obj, name);
     assertTrue(obj instanceof WebAssembly.Global, name);
-    assertEquals(value.value || 0, obj.value, name);
+    assertEquals(value || 0, obj.value, name);
     assertThrows(() => obj.value = 0);
   }
 })();
@@ -44,12 +44,12 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 (function exportMutableGlobal() {
   var builder = new WasmModuleBuilder();
   let globals = [
-    [kWasmI32, 'i32', WasmInitExpr.I32Const(4711)],               // -
-    [kWasmF32, 'f32', WasmInitExpr.F32Const(Math.fround(3.14))],  // -
-    [kWasmF64, 'f64', WasmInitExpr.F64Const(1 / 7)]               // -
+    [kWasmI32, 'i32', 4711, wasmI32Const(4711)],
+    [kWasmF32, 'f32', Math.fround(3.14), wasmF32Const(Math.fround(3.14))],
+    [kWasmF64, 'f64', 1/7, wasmF64Const(1 / 7)]
   ];
-  for (let [index, [type, name, value]] of globals.entries()) {
-    builder.addGlobal(type, true, value).exportAs(name);
+  for (let [index, [type, name, value, bytes]] of globals.entries()) {
+    builder.addGlobal(type, true, bytes).exportAs(name);
     builder.addFunction("get " + name, makeSig([], [type]))
       .addBody([kExprGlobalGet, index])
       .exportFunc();
@@ -59,10 +59,10 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   }
   var instance = builder.instantiate();
 
-  for (let [type, name, value] of globals) {
+  for (let [type, name, value, bytes] of globals) {
     let obj = instance.exports[name];
 
-    assertEquals(value.value || 0, obj.value, name);
+    assertEquals(value || 0, obj.value, name);
 
     // Changing the exported global should change the instance's global.
     obj.value = 1001;

test/mjsunit/wasm/extended-constants.js

@@ -16,13 +16,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let defined_global = builder.addGlobal(
     kWasmI32, false,
-    WasmInitExpr.I32Add(
-      WasmInitExpr.GlobalGet(imported_global_0),
-      WasmInitExpr.I32Mul(
-        WasmInitExpr.GlobalGet(imported_global_1),
-        WasmInitExpr.I32Sub(
-          WasmInitExpr.GlobalGet(imported_global_0),
-          WasmInitExpr.I32Const(1)))));
+    [kExprGlobalGet, imported_global_0, kExprGlobalGet, imported_global_1,
+     kExprGlobalGet, imported_global_0, ...wasmI32Const(1),
+     kExprI32Sub, kExprI32Mul, kExprI32Add]);
 
   builder.addExportOfKind("global", kExternalGlobal, defined_global.index);
 
@@ -49,13 +45,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let defined_global = builder.addGlobal(
     kWasmI64, false,
-    WasmInitExpr.I64Add(
-      WasmInitExpr.GlobalGet(imported_global_0),
-      WasmInitExpr.I64Mul(
-        WasmInitExpr.GlobalGet(imported_global_1),
-        WasmInitExpr.I64Sub(
-          WasmInitExpr.GlobalGet(imported_global_0),
-          WasmInitExpr.I64Const(1)))));
+    [kExprGlobalGet, imported_global_0, kExprI64Const, 1, kExprI64Sub,
+     kExprGlobalGet, imported_global_1, kExprI64Mul,
+     kExprGlobalGet, imported_global_0, kExprI64Add]);
 
   builder.addExportOfKind("global", kExternalGlobal, defined_global.index);
 

test/mjsunit/wasm/externref-globals.js

@@ -549,7 +549,7 @@ function dummy_func() {
   const f_func = builder.addFunction('get_anyfunc_global', kSig_a_v)
   builder.addDeclarativeElementSegment([f_func.index]);
   const g_func = builder.addGlobal(kWasmAnyFunc, true,
-    WasmInitExpr.RefFunc(f_func.index));
+    [kExprRefFunc, f_func.index]);
   // Doing this here to break the cyclic dependency with g_func.
   f_func.addBody([kExprGlobalGet, g_func.index])
     .exportAs('get_anyfunc_global');
@@ -567,9 +567,9 @@ function dummy_func() {
   const import_wasm = builder.addImport('m', 'wasm', sig_index);
   const import_js = builder.addImport('m', 'js', sig_index);
   const g_wasm = builder.addGlobal(kWasmAnyFunc, true,
-                                   WasmInitExpr.RefFunc(import_wasm));
+                                   [kExprRefFunc, import_wasm]);
   const g_js = builder.addGlobal(kWasmAnyFunc, true,
-                                 WasmInitExpr.RefFunc(import_js));
+                                 [kExprRefFunc, import_js]);
   builder.addDeclarativeElementSegment([import_wasm, import_js]);
   builder.addFunction('get_global_wasm', kSig_a_v)
       .addBody([kExprGlobalGet, g_wasm.index])

test/mjsunit/wasm/externref-table.js

@@ -53,7 +53,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   print(arguments.callee.name);
 
   const builder = new WasmModuleBuilder();
-  builder.addDeclarativeElementSegment([WasmInitExpr.RefNull(kWasmFuncRef)],
+  builder.addDeclarativeElementSegment([[kExprRefNull, kFuncRefCode]],
                                         kWasmFuncRef);
   builder.addFunction('drop', kSig_v_v)
       .addBody([kNumericPrefix, kExprElemDrop, 0])
@@ -70,7 +70,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   const builder = new WasmModuleBuilder();
   const table = builder.addTable(kWasmAnyFunc, 10);
-  builder.addDeclarativeElementSegment([WasmInitExpr.RefNull(kWasmFuncRef)],
+  builder.addDeclarativeElementSegment([[kExprRefNull, kFuncRefCode]],
                                        kWasmFuncRef);
   builder.addFunction('init', kSig_v_v)
       .addBody([
@@ -158,7 +158,7 @@ function getDummy(val) {
   let imported_global = builder.addImportedGlobal('m', 'n', extern_type, false);
   let global = builder.addGlobal(kWasmExternRef, true).exportAs('global');
   let table = builder.addTable(extern_type, 2, 10,
-                               WasmInitExpr.GlobalGet(imported_global))
+                               [kExprGlobalGet, imported_global])
   builder.addFunction(
       'setup', makeSig([extern_type, extern_type], []))
     .addBody([

test/mjsunit/wasm/gc-nominal.js

@@ -58,6 +58,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   print(arguments.callee.name);
   let builder = new WasmModuleBuilder();
   builder.setNominal();
+  builder.setEarlyDataCountSection();
   let array_type_index = builder.addArray(kWasmI16, true);
 
   let dummy_byte = 0xff;
@@ -70,9 +71,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let global = builder.addGlobal(
     wasmRefType(array_type_index), true,
-    WasmInitExpr.ArrayInitFromDataStatic(
-      array_type_index, data_segment,
-      [WasmInitExpr.I32Const(1), WasmInitExpr.I32Const(2)], builder));
+    [...wasmI32Const(1), ...wasmI32Const(2),
+     kGCPrefix, kExprArrayInitFromDataStatic, array_type_index, data_segment],
+    builder);
 
   builder.addFunction("global_get", kSig_i_i)
     .addBody([
@@ -117,6 +118,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   print(arguments.callee.name);
   let builder = new WasmModuleBuilder();
   builder.setNominal();
+  builder.setEarlyDataCountSection();
   let array_type_index = builder.addArray(kWasmI16, true);
 
   let dummy_byte = 0xff;
@@ -129,11 +131,10 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let global = builder.addGlobal(
     wasmRefType(array_type_index), true,
-    WasmInitExpr.ArrayInitFromData(
-      array_type_index, data_segment,
-      [WasmInitExpr.I32Const(1), WasmInitExpr.I32Const(2),
-       WasmInitExpr.RttCanon(array_type_index)],
-      builder));
+    [...wasmI32Const(1), ...wasmI32Const(2),
+     kGCPrefix, kExprRttCanon, array_type_index,
+     kGCPrefix, kExprArrayInitFromData, array_type_index, data_segment],
+    builder);
 
   builder.addFunction("global_get", kSig_i_i)
     .addBody([

test/mjsunit/wasm/gc-optimizations.js

@@ -385,7 +385,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   ]);
 
   let global = builder.addGlobal(
-      wasmOptRefType(struct_2), true, WasmInitExpr.RefNull(struct_2));
+      wasmOptRefType(struct_2), true, [kExprRefNull, struct_2]);
 
   // The three alocations should be folded.
   builder.addFunction("main", kSig_i_i)

test/mjsunit/wasm/globals.js

@@ -101,16 +101,15 @@ function TestExported(type, val, expected) {
   assertEquals(expected, instance.exports.foo.value);
 }
 
-TestExported(kWasmI32, WasmInitExpr.I32Const(455.5), 455);
-TestExported(kWasmF32, WasmInitExpr.F32Const(-999.34343),
+TestExported(kWasmI32, wasmI32Const(455.5), 455);
+TestExported(kWasmF32, wasmF32Const(-999.34343),
              Math.fround(-999.34343));
-TestExported(kWasmF64, WasmInitExpr.F64Const(87347.66666), 87347.66666);
+TestExported(kWasmF64, wasmF64Const(87347.66666), 87347.66666);
 
 (function TestI64Exported() {
   var builder = new WasmModuleBuilder();
   builder.addGlobal(kWasmI32);  // pad
-  builder.addGlobal(kWasmI64, false, WasmInitExpr.I64Const(1234))
-      .exportAs("foo");
+  builder.addGlobal(kWasmI64, false, wasmI64Const(1234)).exportAs("foo");
   builder.addGlobal(kWasmI32);  // pad
 
   var instance = builder.instantiate();
@@ -123,8 +122,7 @@ function TestImportedExported(type, val, expected) {
   var builder = new WasmModuleBuilder();
   var i = builder.addImportedGlobal("ttt", "foo", type);
   builder.addGlobal(kWasmI32);  // pad
-  builder.addGlobal(type, false, WasmInitExpr.GlobalGet(i))
-      .exportAs("bar");
+  builder.addGlobal(type, false, [kExprGlobalGet, i]).exportAs("bar");
   builder.addGlobal(kWasmI32);  // pad
 
   var instance = builder.instantiate({ttt: {foo: val}});
@@ -140,7 +138,7 @@ function TestGlobalIndexSpace(type, val) {
   var builder = new WasmModuleBuilder();
   var im = builder.addImportedGlobal("nnn", "foo", type);
   assertEquals(0, im);
-  var def = builder.addGlobal(type, false, WasmInitExpr.GlobalGet(im));
+  var def = builder.addGlobal(type, false, [kExprGlobalGet, im]);
   assertEquals(1, def.index);
 
   var sig = makeSig([], [type]);

test/mjsunit/wasm/import-table.js

@@ -41,8 +41,8 @@ let kTableSize = 50;
     let f17 = addConstFunc(builder, 17);
     builder.addExport("f15", f15);
     builder.addExport("f17", f17);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(15), [f15]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(1), [call.index]);
+    builder.addActiveElementSegment(0, wasmI32Const(15), [f15]);
+    builder.addActiveElementSegment(0, wasmI32Const(1), [call.index]);
 
     var mod1 = builder.toModule();
   }
@@ -62,10 +62,10 @@ let kTableSize = 50;
         ])
         .exportAs("call");
     let f26 = addConstFunc(builder, 26);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(17), [f17]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(21), [f21]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(26), [f26]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(5), [call.index]);
+    builder.addActiveElementSegment(0, wasmI32Const(17), [f17]);
+    builder.addActiveElementSegment(0, wasmI32Const(21), [f21]);
+    builder.addActiveElementSegment(0, wasmI32Const(26), [f26]);
+    builder.addActiveElementSegment(0, wasmI32Const(5), [call.index]);
 
     var mod2 = builder.toModule();
   }
@@ -89,7 +89,7 @@ let kTableSize = 50;
 })();
 
 function addConstFuncUsingGlobal(builder, val) {
-  let g = builder.addGlobal(kWasmI32, false, WasmInitExpr.I32Const(val));
+  let g = builder.addGlobal(kWasmI32, false, wasmI32Const(val));
   return builder.addFunction("global" + val, kSig_i_v)
     .addBody([kExprGlobalGet, g.index]).index;
 }
@@ -112,8 +112,8 @@ function addConstFuncUsingGlobal(builder, val) {
     let f18 = addConstFuncUsingGlobal(builder, 18);
     builder.addExport("f14", f14);
     builder.addExport("f18", f18);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(14), [f14]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(1), [call.index]);
+    builder.addActiveElementSegment(0, wasmI32Const(14), [f14]);
+    builder.addActiveElementSegment(0, wasmI32Const(1), [call.index]);
 
     var mod1 = builder.toModule();
   }
@@ -133,10 +133,10 @@ function addConstFuncUsingGlobal(builder, val) {
         ])
         .exportAs("call");
     let f28 = addConstFuncUsingGlobal(builder, 28);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(18), [f18]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(22), [f22]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(28), [f28]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(5), [call.index]);
+    builder.addActiveElementSegment(0, wasmI32Const(18), [f18]);
+    builder.addActiveElementSegment(0, wasmI32Const(22), [f22]);
+    builder.addActiveElementSegment(0, wasmI32Const(28), [f28]);
+    builder.addActiveElementSegment(0, wasmI32Const(5), [call.index]);
 
     var mod2 = builder.toModule();
   }
@@ -192,8 +192,8 @@ function addConstFuncUsingMemory(builder, val) {
     let f19 = addConstFuncUsingMemory(builder, 19);
     builder.addExport("f13", f13);
     builder.addExport("f19", f19);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(13), [f13]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(1), [call.index]);
+    builder.addActiveElementSegment(0, wasmI32Const(13), [f13]);
+    builder.addActiveElementSegment(0, wasmI32Const(1), [call.index]);
 
     var mod1 = builder.toModule();
   }
@@ -215,10 +215,10 @@ function addConstFuncUsingMemory(builder, val) {
         ])
         .exportAs("call");
     let f29 = addConstFuncUsingMemory(builder, 29);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(19), [f19]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(23), [f23]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(29), [f29]);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(5), [call.index]);
+    builder.addActiveElementSegment(0, wasmI32Const(19), [f19]);
+    builder.addActiveElementSegment(0, wasmI32Const(23), [f23]);
+    builder.addActiveElementSegment(0, wasmI32Const(29), [f29]);
+    builder.addActiveElementSegment(0, wasmI32Const(5), [call.index]);
 
     var mod2 = builder.toModule();
   }

test/mjsunit/wasm/indirect-call-non-zero-table.js

@@ -67,12 +67,12 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     .exportAs('return_call_invalid_sig');
 
   // We want to crash if we call through the table with index 0.
-  builder.addActiveElementSegment(placeholder, WasmInitExpr.I32Const(0),
+  builder.addActiveElementSegment(placeholder, wasmI32Const(0),
     [f_unreachable, f_unreachable, f_unreachable]);
-  builder.addActiveElementSegment(table1, WasmInitExpr.I32Const(0),
+  builder.addActiveElementSegment(table1, wasmI32Const(0),
                                   [f1, f2, f3]);
   // Keep one slot in table2 uninitialized. We should trap if we call it.
-  builder.addActiveElementSegment(table2, WasmInitExpr.I32Const(1),
+  builder.addActiveElementSegment(table2, wasmI32Const(1),
     [f_unreachable, f_unreachable, f4, f5]);
 
   const instance = builder.instantiate();
@@ -127,7 +127,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
       kExprCallIndirect, sig_index, t1])
     .exportAs('call');
 
-  builder.addActiveElementSegment(t1, WasmInitExpr.GlobalGet(g), [f1.index]);
+  builder.addActiveElementSegment(t1, [kExprGlobalGet, g], [f1.index]);
   const base1 = 3;
   const base2 = 5;
 
@@ -171,8 +171,7 @@ function js_div(a, b) { return (a / b) | 0; }
   builder.addFunction("placeholder", sig_index)
     .addBody([kExprLocalGet, 0]);
 
-  builder.addActiveElementSegment(table_index, WasmInitExpr.GlobalGet(g),
-                                  [div]);
+  builder.addActiveElementSegment(table_index, [kExprGlobalGet, g], [div]);
   builder.addFunction("main", kSig_i_ii)
     .addBody([
       kExprI32Const, 55,  // --

test/mjsunit/wasm/indirect-calls.js

@@ -169,7 +169,7 @@ function AddFunctions(builder) {
       .exportAs("main");
 
     builder.setTableBounds(length, length);
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(base),
+    builder.addActiveElementSegment(0, wasmI32Const(base),
                                     [f.add.index, f.sub.index, f.mul.index]);
 
     return builder.instantiate();
@@ -208,7 +208,7 @@ function AddFunctions(builder) {
 
   builder.setTableBounds(10, 10);
   var g = builder.addImportedGlobal("fff", "base", kWasmI32);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g),
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g],
                                   [f.mul.index, f.add.index, f.sub.index]);
 
   var module = new WebAssembly.Module(builder.toBuffer());

test/mjsunit/wasm/indirect-tables.js

@@ -50,7 +50,7 @@ function js_div(a, b) { return (a / b) | 0; }
 
   builder.setTableBounds(10, 10);
   let g = builder.addImportedGlobal("q", "base", kWasmI32);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g),
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g],
                                   [f.mul.index, f.add.index, f.sub.index, d]);
   builder.addExportOfKind("table", kExternalTable, 0);
 
@@ -109,7 +109,7 @@ function js_div(a, b) { return (a / b) | 0; }
   let f = AddFunctions(builder);
   builder.setTableBounds(kTableSize, kTableSize);
   let g = builder.addImportedGlobal("q", "base", kWasmI32);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g),
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g],
                                   [f.mul.index, f.add.index, f.sub.index, d]);
   builder.addExportOfKind("table", kExternalTable, 0);
 
@@ -179,7 +179,7 @@ function js_div(a, b) { return (a / b) | 0; }
   builder.addImportedTable("q", "table", kTableSize, kTableSize);
   let g = builder.addImportedGlobal("q", "base", kWasmI32);
   let f = AddFunctions(builder);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g),
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g],
                                   [f.mul.index, f.add.index, f.sub.index, d]);
   builder.addFunction("main", kSig_i_ii)
     .addBody([
@@ -256,7 +256,7 @@ function js_div(a, b) { return (a / b) | 0; }
       kExprLocalGet, 0,
       kExprCallIndirect, sig_index, kTableZero])  // --
     .exportAs("main");
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g), [f.index]);
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g], [f.index]);
 
   let module = new WebAssembly.Module(builder.toBuffer());
 
@@ -297,7 +297,7 @@ function js_div(a, b) { return (a / b) | 0; }
     .exportAs("main");
 
   builder.setTableBounds(kTableSize, kTableSize);
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [f1.index]);
+  builder.addActiveElementSegment(0, wasmI32Const(0), [f1.index]);
   builder.addExportOfKind("table", kExternalTable, 0);
 
   var m1 = new WebAssembly.Module(builder.toBuffer());
@@ -316,7 +316,7 @@ function js_div(a, b) { return (a / b) | 0; }
     .exportAs("main");
 
   builder.addImportedTable("z", "table", kTableSize, kTableSize);
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(1), [f2.index]);
+  builder.addActiveElementSegment(0, wasmI32Const(1), [f2.index]);
 
   var m2 = new WebAssembly.Module(builder.toBuffer());
 
@@ -411,7 +411,7 @@ function js_div(a, b) { return (a / b) | 0; }
       kExprLocalGet, 0,
       kExprCallIndirect, sig_index, kTableZero])  // --
     .exportAs("main");
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g), [g]);
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g], [g]);
   let module = new WebAssembly.Module(builder.toBuffer());
 
   var instances = [];
@@ -542,7 +542,7 @@ function js_div(a, b) { return (a / b) | 0; }
       let offset = i + 1;
       let len = i + 2;
       let index = indexes[i];
-      builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+      builder.addActiveElementSegment(0, wasmI32Const(offset),
                                       new Array(len).fill(index));
     }
 
@@ -587,7 +587,7 @@ function js_div(a, b) { return (a / b) | 0; }
   builder1.setName('module_1');
   builder1.addFunction('f', kSig_i_i).addBody([kExprLocalGet, 0]);
   builder1.addImportedTable('z', 'table');
-  builder1.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0]);
+  builder1.addActiveElementSegment(0, wasmI32Const(0), [0]);
   let module1 = new WebAssembly.Module(builder1.toBuffer());
   let instance1 =
       new WebAssembly.Instance(module1, {z: {table: instance0.exports.table}});
@@ -626,7 +626,7 @@ function js_div(a, b) { return (a / b) | 0; }
   builder.addFunction('main', kSig_i_v)
          .addBody([kExprI32Const, 0, kExprI32LoadMem, 0, 0]);
   builder.addImportedTable('', 'table');
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0]);
+  builder.addActiveElementSegment(0, wasmI32Const(0), [0]);
   builder.addImportedMemory('', 'memory', 1);
 
 
@@ -734,7 +734,7 @@ function js_div(a, b) { return (a / b) | 0; }
 
   builder.setTableBounds(10, 10);
   let g = builder.addImportedGlobal("q", "base", kWasmI32);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g), [j, w]);
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g], [j, w]);
 
   let module = new WebAssembly.Module(builder.toBuffer());
   for (var i = 0; i < 5; i++) {
@@ -783,7 +783,7 @@ function js_div(a, b) { return (a / b) | 0; }
     .exportAs("main");
 
   let g = builder.addImportedGlobal("q", "base", kWasmI32);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g), [j, w]);
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g], [j, w]);
 
   let module = new WebAssembly.Module(builder.toBuffer());
   for (var i = 0; i < 5; i++) {
@@ -824,7 +824,7 @@ function js_div(a, b) { return (a / b) | 0; }
         kExprCallIndirect, 0, kTableZero
       ])
       .exportFunc();
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0, 1, 1, 0]);
+    builder.addActiveElementSegment(0, wasmI32Const(0), [0, 1, 1, 0]);
 
     return builder.instantiate({q: {f2: i1.exports.f2, f1: i1.exports.f1}});
   })();
@@ -887,7 +887,7 @@ function js_div(a, b) { return (a / b) | 0; }
       ])
       .exportFunc();
     builder.exportMemoryAs("memory");
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0, 1, 2, 3]);
+    builder.addActiveElementSegment(0, wasmI32Const(0), [0, 1, 2, 3]);
     var instance = builder.instantiate({q: {f1: f100, f2: f200, f3: f300}});
     setMemI32(instance, 0, 5000000);
     setMemI32(instance, 4, 6000000);
@@ -905,11 +905,11 @@ function js_div(a, b) { return (a / b) | 0; }
   print(arguments.callee.name);
   let builder = new WasmModuleBuilder();
   let global = builder.addGlobal(kWasmFuncRef, false,
-                                 WasmInitExpr.RefNull(kWasmFuncRef));
+                                 [kExprRefNull, kFuncRefCode]);
   let table = builder.addTable(kWasmFuncRef, 10, 10);
   builder.addActiveElementSegment(
-      table.index, WasmInitExpr.I32Const(0),
-      [WasmInitExpr.GlobalGet(global.index)], kWasmFuncRef);
+      table.index, wasmI32Const(0),
+      [[kExprGlobalGet, global.index]], kWasmFuncRef);
   builder.addExportOfKind("table", kExternalTable, table.index);
 
   assertThrows(

test/mjsunit/wasm/multi-table-element-section.js

@@ -32,7 +32,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     const f2 = builder_for_import.addFunction('f2', kSig_i_v)
       .addBody([kExprI32Const, value2]).index;
 
-    builder_for_import.addActiveElementSegment(t1, WasmInitExpr.I32Const(offset1),
+    builder_for_import.addActiveElementSegment(t1, wasmI32Const(offset1),
                                          [f1, f2]);
     const instance_for_import = builder_for_import.instantiate();
     const table1 = instance_for_import.exports.table;
@@ -56,11 +56,11 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     .addBody([kExprI32Const, value5]).index;
 
 
-  builder.addActiveElementSegment(t2, WasmInitExpr.I32Const(offset2), [f3, f4]);
-  builder.addActiveElementSegment(t3, WasmInitExpr.I32Const(offset3), [f5, f4]);
-  builder.addActiveElementSegment(t4, WasmInitExpr.I32Const(offset4), [f3, f5]);
+  builder.addActiveElementSegment(t2, wasmI32Const(offset2), [f3, f4]);
+  builder.addActiveElementSegment(t3, wasmI32Const(offset3), [f5, f4]);
+  builder.addActiveElementSegment(t4, wasmI32Const(offset4), [f3, f5]);
   // Add one more overlapping offset
-  builder.addActiveElementSegment(t4, WasmInitExpr.I32Const(offset4 + 1),
+  builder.addActiveElementSegment(t4, wasmI32Const(offset4 + 1),
                                   [f4, f3]);
 
   const instance = builder.instantiate(instance_for_import);

test/mjsunit/wasm/reference-globals.js

@@ -20,7 +20,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
       .exportFunc();
 
     builder.addGlobal(wasmRefType(sig_index), false,
-                      WasmInitExpr.RefFunc(addition_index))
+                      [kExprRefFunc, addition_index.index])
            .exportAs("global");
     builder.addGlobal(wasmOptRefType(wrong_sig_index), false)
       .exportAs("mistyped_global");
@@ -122,25 +122,21 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   var global0 = builder.addGlobal(
       wasmRefType(struct_index), false,
-      WasmInitExpr.StructNewWithRtt(
-          struct_index,
-          [WasmInitExpr.I32Const(field2_value),
-           WasmInitExpr.RttCanon(struct_index)]));
+      [...wasmI32Const(field2_value),
+       kGCPrefix, kExprRttCanon, struct_index,
+       kGCPrefix, kExprStructNewWithRtt, struct_index]);
 
   var global = builder.addGlobal(
       wasmRefType(composite_struct_index), false,
-      WasmInitExpr.StructNewWithRtt(
-          composite_struct_index,
-          [WasmInitExpr.I32Const(field1_value),
-           WasmInitExpr.GlobalGet(global0.index),
-           WasmInitExpr.I32Const(field3_value),
-           WasmInitExpr.RttCanon(composite_struct_index)]));
+      [...wasmI32Const(field1_value), kExprGlobalGet, global0.index,
+       ...wasmI32Const(field3_value),
+       kGCPrefix, kExprRttCanon, composite_struct_index,
+       kGCPrefix, kExprStructNewWithRtt, composite_struct_index]);
 
   var global_default = builder.addGlobal(
     wasmRefType(composite_struct_index), false,
-    WasmInitExpr.StructNewDefaultWithRtt(
-      composite_struct_index,
-      WasmInitExpr.RttCanon(composite_struct_index)));
+    [kGCPrefix, kExprRttCanon, composite_struct_index,
+     kGCPrefix, kExprStructNewDefaultWithRtt, composite_struct_index]);
 
   builder.addFunction("field_1", kSig_i_v)
     .addBody([
@@ -202,15 +198,13 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   var global0 = builder.addGlobal(
       kWasmI32, false,
-      WasmInitExpr.I32Const(element0_value));
+      wasmI32Const(element0_value));
 
   var global = builder.addGlobal(
       wasmRefType(array_index), false,
-      WasmInitExpr.ArrayInit(
-          array_index,
-          [WasmInitExpr.GlobalGet(global0.index),
-           WasmInitExpr.I32Const(element1_value),
-           WasmInitExpr.RttCanon(array_index)]));
+      [kExprGlobalGet, global0.index, ...wasmI32Const(element1_value),
+       kGCPrefix, kExprRttCanon, array_index,
+       kGCPrefix, kExprArrayInit, array_index, 2]);
 
   builder.addFunction("get_element", kSig_i_i)
     .addBody([
@@ -237,22 +231,17 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   var global0 = builder.addGlobal(
       wasmRefType(struct_index), false,
-      WasmInitExpr.StructNewWithRtt(
-          struct_index,
-          [WasmInitExpr.I32Const(element0_value),
-           WasmInitExpr.RttCanon(struct_index)]));
+      [...wasmI32Const(element0_value), kGCPrefix, kExprRttCanon, struct_index,
+       kGCPrefix, kExprStructNewWithRtt, struct_index]);
 
   var global = builder.addGlobal(
       wasmRefType(array_index), false,
-      WasmInitExpr.ArrayInit(
-          array_index,
-          [WasmInitExpr.GlobalGet(global0.index),
-           WasmInitExpr.RefNull(struct_index),
-           WasmInitExpr.StructNewWithRtt(
-              struct_index,
-              [WasmInitExpr.I32Const(element2_value),
-               WasmInitExpr.RttCanon(struct_index)]),
-           WasmInitExpr.RttCanon(array_index)]));
+      [kExprGlobalGet, global0.index, kExprRefNull, struct_index,
+       ...wasmI32Const(element2_value),
+       kGCPrefix, kExprRttCanon, struct_index,
+       kGCPrefix, kExprStructNewWithRtt, struct_index,
+       kGCPrefix, kExprRttCanon, array_index,
+       kGCPrefix, kExprArrayInit, array_index, 3]);
 
   builder.addFunction("element0", kSig_i_v)
     .addBody([
@@ -294,8 +283,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 
   let global = builder.addGlobal(
       wasmRefType(array_index), true,
-      WasmInitExpr.ArrayInitStatic(array_index, values.map(
-          value => WasmInitExpr.I31New(WasmInitExpr.I32Const(value)))));
+      [...values.flatMap(
+        value => [...wasmI32Const(value), kGCPrefix, kExprI31New]),
+       kGCPrefix, kExprArrayInitStatic, array_index, 5]);
 
   for (signed of [true, false]) {
     builder.addFunction(`get_${signed ? "s" : "u"}`, kSig_i_i)
@@ -325,7 +315,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   let builder = new WasmModuleBuilder();
 
   builder.addGlobal(kWasmI31Ref, false,
-                    WasmInitExpr.I31New(WasmInitExpr.I64Const(0)));
+                    [...wasmI64Const(0), kGCPrefix, kExprI31New]);
 
   assertThrows(() => builder.instantiate(), WebAssembly.CompileError,
                /i31.new\[0\] expected type i32, found i64.const of type i64/);

test/mjsunit/wasm/reference-tables.js

@@ -117,7 +117,7 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
           .exportFunc();
 
   var table = builder.addTable(wasmRefType(binary_type), 3, 3,
-                               WasmInitExpr.RefFunc(addition.index));
+                               [kExprRefFunc, addition.index]);
 
   builder.addFunction('init', kSig_v_v)
       .addBody([
@@ -159,11 +159,11 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
 
   let table = builder.addTable(kWasmAnyRef, 4, 4);
   builder.addActiveElementSegment(
-    table, WasmInitExpr.I32Const(0),
-    [WasmInitExpr.RefFunc(successor.index),
-     WasmInitExpr.RefFunc(subtraction.index),
-     WasmInitExpr.StructNew(struct_type, [WasmInitExpr.I32Const(10)]),
-     WasmInitExpr.RefNull(kWasmEqRef)],
+    table, wasmI32Const(0),
+    [[kExprRefFunc, successor.index],
+     [kExprRefFunc, subtraction.index],
+     [...wasmI32Const(10), kGCPrefix, kExprStructNew, struct_type],
+     [kExprRefNull, kEqRefCode]],
     kWasmAnyRef);
 
   // return static_cast<i->i>(table[0])(local_0)

test/mjsunit/wasm/return-calls.js

@@ -140,7 +140,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   // Arbitrary location in the table.
   const tableIndex = 3;
 
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(tableIndex),[pick]);
+  builder.addActiveElementSegment(0, wasmI32Const(tableIndex),[pick]);
 
   let main = builder.addFunction("main", kSig_i_iii)
         .addBody([

test/mjsunit/wasm/simd-globals.js

@@ -12,8 +12,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
 (function TestS128GlobalInitialization() {
   var builder = new WasmModuleBuilder();
   var g = builder.addGlobal(
-    kWasmS128, false, WasmInitExpr.S128Const(
-      [1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0]));
+    kWasmS128, false,
+    [kSimdPrefix, kExprS128Const,
+     1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0]);
 
   // Check that all lanes have the right values by creating 4 functions that
   // extract each lane.

test/mjsunit/wasm/speculative-inlining.js

@@ -23,7 +23,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     .addBody([kExprLocalGet, 0, kExprI32Const, 1, kExprI32Sub]);
 
   let global = builder.addGlobal(wasmRefType(0), false,
-                                 WasmInitExpr.RefFunc(callee.index));
+                                 [kExprRefFunc, callee.index]);
 
   // g(x) = f(5) + x
   builder.addFunction("main", kSig_i_i)
@@ -55,9 +55,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     .addBody([kExprLocalGet, 0, kExprI32Const, 2, kExprI32Sub]);
 
   let global0 = builder.addGlobal(wasmRefType(sig_index), false,
-                                  WasmInitExpr.RefFunc(callee0.index));
+                                  [kExprRefFunc, callee0.index]);
   let global1 = builder.addGlobal(wasmRefType(sig_index), false,
-                                  WasmInitExpr.RefFunc(callee1.index));
+                                  [kExprRefFunc, callee1.index]);
 
   // g(x, y) = if (y) { h(5) + x } else { f(7) + x }
   builder.addFunction("main", kSig_i_ii)
@@ -95,7 +95,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     .addBody([kExprLocalGet, 0, kExprI32Const, 1, kExprI32Sub]);
 
   let global = builder.addGlobal(wasmRefType(0), false,
-                                 WasmInitExpr.RefFunc(callee.index));
+                                 [kExprRefFunc, callee.index]);
 
   // g(x) = f(5 + x)
   builder.addFunction("main", kSig_i_i)
@@ -127,9 +127,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
     .addBody([kExprLocalGet, 0, kExprI32Const, 2, kExprI32Sub]);
 
   let global0 = builder.addGlobal(wasmRefType(sig_index), false,
-                                 WasmInitExpr.RefFunc(callee0.index));
+                                 [kExprRefFunc, callee0.index]);
   let global1 = builder.addGlobal(wasmRefType(sig_index), false,
-                                 WasmInitExpr.RefFunc(callee1.index));
+                                 [kExprRefFunc, callee1.index]);
 
   // g(x, y) = if (y) { h(x) } else { f(x) }
   builder.addFunction("main", kSig_i_ii)

test/mjsunit/wasm/stringrefs-exec.js

@@ -154,11 +154,10 @@ function makeWtf16TestDataSegment() {
 
     builder.addFunction("string_const" + index, kSig_w_v)
       .exportFunc()
-      .addBody([
-        kGCPrefix, kExprStringConst, index
-      ]);
+      .addBody([kGCPrefix, kExprStringConst, index]);
 
-    builder.addGlobal(kWasmStringRef, false, WasmInitExpr.StringConst(index))
+    builder.addGlobal(kWasmStringRef, false,
+                      [kGCPrefix, kExprStringConst, index])
       .exportAs("global" + index);
   }
 

test/mjsunit/wasm/stringrefs-invalid.js

@@ -17,12 +17,12 @@ let enableMessage = 'enable with --experimental-wasm-stringref'
 assertInvalid(builder => builder.addLiteralStringRef("foo"),
               `unexpected section <StringRef> (${enableMessage}) @+10`);
 
-for (let [name, code] of [['string', kWasmStringRef],
-                          ['stringview_wtf8', kWasmStringViewWtf8],
-                          ['stringview_wtf16', kWasmStringViewWtf16],
-                          ['stringview_iter', kWasmStringViewIter]]) {
+for (let [name, code] of [['string', kStringRefCode],
+                          ['stringview_wtf8', kStringViewWtf8Code],
+                          ['stringview_wtf16', kStringViewWtf16Code],
+                          ['stringview_iter', kStringViewIterCode]]) {
   let message = `invalid value type '${name}ref', ${enableMessage}`;
-  let default_init = WasmInitExpr.RefNull(code);
+  let default_init = [kExprRefNull, code];
 
   assertInvalid(b => b.addType(makeSig([code], [])),
                 `${message} @+13`);

test/mjsunit/wasm/stringrefs-valid.js

@@ -23,11 +23,11 @@ function assertInvalid(fn, message) {
 
 assertValid(builder => builder.addLiteralStringRef("foo"));
 
-for (let [name, code] of [['string', kWasmStringRef],
-                          ['stringview_wtf8', kWasmStringViewWtf8],
-                          ['stringview_wtf16', kWasmStringViewWtf16],
-                          ['stringview_iter', kWasmStringViewIter]]) {
-  let default_init = WasmInitExpr.RefNull(code);
+for (let [name, code] of [['string', kStringRefCode],
+                          ['stringview_wtf8', kStringViewWtf8Code],
+                          ['stringview_wtf16', kStringViewWtf16Code],
+                          ['stringview_iter', kStringViewIterCode]]) {
+  let default_init = [kExprRefNull, code];
 
   assertValid(b => b.addType(makeSig([code], [])));
   assertValid(b => b.addStruct([makeField(code, true)]));

test/mjsunit/wasm/table-access.js

@@ -117,9 +117,9 @@ const dummy_func = exports.set_table_func1;
 
   const offset1 = 3;
   const offset2 = 9;
-  builder.addActiveElementSegment(t1, WasmInitExpr.I32Const(offset1),
+  builder.addActiveElementSegment(t1, wasmI32Const(offset1),
                                   [f1.index, f2.index]);
-  builder.addActiveElementSegment(t2, WasmInitExpr.I32Const(offset2),
+  builder.addActiveElementSegment(t2, wasmI32Const(offset2),
                                   [f3.index, f1.index]);
 
   const instance = builder.instantiate();

test/mjsunit/wasm/table-get.js

@@ -11,7 +11,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   const f1 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 11]);
   const f2 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 22]);
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, f2.index]);
 
   const instance = builder.instantiate();
@@ -28,7 +28,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   const f2 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 22])
                     .exportAs("f2");
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, f2.index]);
 
   const instance = builder.instantiate();
@@ -44,9 +44,9 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   const f1 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 11]);
   const f2 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 22]);
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, f2.index]);
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset + 1),
+  builder.addActiveElementSegment(0, wasmI32Const(offset + 1),
                                   [f1.index, f2.index]);
 
   const instance = builder.instantiate();
@@ -63,7 +63,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
                     .addBody([kExprI32Const, 11]).exportAs("f1");
   const f2 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 22]);
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, f1.index, f1.index]);
 
   const instance = builder.instantiate();
@@ -84,7 +84,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   const f1 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 11]);
   const f2 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 22]);
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, f1.index, f1.index]);
 
   const instance = builder.instantiate();
@@ -104,7 +104,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   const f1 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 11]);
   const f2 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 22]);
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, f1.index, f1.index]);
 
   const instance = builder.instantiate();
@@ -119,7 +119,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   const f1 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 11]);
   const f2 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 22]);
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, f1.index, f1.index]);
 
   const instance = builder.instantiate();
@@ -134,7 +134,7 @@ d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
   const import1 = builder.addImport("q", "fun", kSig_i_ii);
   const f1 = builder.addFunction('f', kSig_i_v).addBody([kExprI32Const, 11]);
   const offset = 3;
-  builder.addActiveElementSegment(0, WasmInitExpr.I32Const(offset),
+  builder.addActiveElementSegment(0, wasmI32Const(offset),
                                   [f1.index, import1]);
 
   const instance = builder.instantiate({q: {fun: () => 33}});

test/mjsunit/wasm/table-grow.js

@@ -132,7 +132,7 @@ let id = (() => {  // identity exported function
 
   builder.addImportedTable("q", "table", 5, 32);
   let g = builder.addImportedGlobal("q", "base", kWasmI32);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g),
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g],
       [funcs.mul.index, funcs.add.index, funcs.sub.index]);
   builder.addExportOfKind("table", kExternalTable, 0);
   let module = new WebAssembly.Module(builder.toBuffer());
@@ -179,7 +179,7 @@ let id = (() => {  // identity exported function
   let t = builder.addImport("q", "exp_ten", sig_i_v);
 
   builder.setTableBounds(7, 35);
-  builder.addActiveElementSegment(0, WasmInitExpr.GlobalGet(g1), [a, i, t]);
+  builder.addActiveElementSegment(0, [kExprGlobalGet, g1], [a, i, t]);
 
   builder.addExportOfKind("table", kExternalTable, 0);
   let module = new WebAssembly.Module(builder.toBuffer());
@@ -213,7 +213,7 @@ let id = (() => {  // identity exported function
 
   builder1.addImportedTable("q", "table", 6, 36);
   builder1.addActiveElementSegment(
-      0, WasmInitExpr.GlobalGet(g),
+      0, [kExprGlobalGet, g],
       [funcs.mul.index, funcs.add.index, funcs.sub.index]);
   let module1 = new WebAssembly.Module(builder1.toBuffer());
 
@@ -265,7 +265,7 @@ let id = (() => {  // identity exported function
         kExprLocalGet, 0,
         kExprCallIndirect, index_i_ii, kTableZero])
       .exportAs("main");
-    builder.addActiveElementSegment(0, WasmInitExpr.I32Const(0), [0]);
+    builder.addActiveElementSegment(0, wasmI32Const(0), [0]);
     return new WebAssembly.Module(builder.toBuffer());
   }
 

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

@@ -195,7 +195,8 @@ function instantiate(buffer, ffi) {
     builder.addType(kSig_i_i);
     builder.addFunction(undefined, i)
            .addBody([kExprLocalGet, 0]);
-    builder.addGlobal(wasmRefType(i), false, WasmInitExpr.RefFunc(i));
+    builder.addGlobal(wasmRefType(i), false,
+                      [kExprRefFunc, ...wasmSignedLeb(i)]);
   }
   for (let i of indices) {
     builder.addFunction('f_' + i, makeSig([], [wasmRefType(i)]))