Adds paired array and typed array representations for arrays and pair…

src/engine/Instance.v3

@@ -101,23 +101,12 @@ class Instance(module: Module, imports: Array<Exportable>) {
 			}
 			Const(val) => return val;
 			I31(val) => {
-				var v = evalInitExpr(val);
-				return Value.I31(u31.view(Values.unbox_i(v)));
-			}
-			Array(t, len, elem) => {
-				var vlen = Values.unbox_i(evalInitExpr(len));
-				var vvals = Array<Value>.new(vlen); // TODO: check for OOM
-				var velem = evalInitExpr(elem);
-				for (i < vvals.length) vvals[i] = velem;
-				return Value.Ref(HeapArray.new(t.array, vvals));
-			}
-			FixedArray(t, vals) => {
-				var vvals = Arrays.map(vals, evalInitExpr);
-				return Value.Ref(HeapArray.new(t.array, vvals));
+				return Value.I31(u31.view(Values.unbox_i(evalInitExpr(val))));
 			}
+			Array(t, len, elem),
+			FixedArray(t, vals),
 			Struct(t, vals) => {
-				var vvals = Arrays.map(vals, evalInitExpr);
-				return Value.Ref(HeapStruct.new(t.sdecl, vvals));
+				return Value.Ref(evalInitExprObject(init));
 			}
 			ArrayNewData(t, data_index, offset, len) => {
 				var voffset = evalInitExpr(offset);
@@ -137,6 +126,100 @@ class Instance(module: Module, imports: Array<Exportable>) {
 			I64_MUL(a, b) => return Value.I64(Values.unbox_w(evalInitExpr(a)) * Values.unbox_w(evalInitExpr(b)));
 		}
 	}
+	// most init exprs are pure and can be evaluated repeatedly, but object ones are not pure
+	def initExprCacheObject = HashMap<InitExpr, Object>.new(fun (ie: InitExpr) => int.!(ie.tag), InitExpr.==);
+	def evalInitExprObject(init: InitExpr) -> Object {
+		if (initExprCacheObject.has(init)) return initExprCacheObject[init];
+		match (init) {
+			FuncRefNull,
+			RefNull(ht),
+			ExternRefNull => return null;
+			Global(global_index, g) => {
+				return Values.unbox<Object>(globals[global_index].get());
+			}
+			FuncRef(func_index, f) => {
+				return functions[func_index];
+			}
+			Const(val) => return Values.unbox<Object>(val); 
+			I31(val) => {
+				return ObjectI31.new(u31.view(Values.unbox_i(evalInitExpr(val))));
+			}
+			Array(t, len, elem) => {
+				var vlen = Values.unbox_i(evalInitExpr(len));
+				var decl = t.array;
+				var st = decl.elem_types[0];
+				var velem = evalInitExpr(elem);
+				var obj: Object;
+				if (ObjReps.arrayMode == ArrayMode.Original) {
+					var vvals = Array<Value>.new(vlen);
+					for (i < vvals.length) vvals[i] = velem;
+					obj = HeapArrayValue.new(t.array, vvals);
+				} else {
+					obj = ObjectRuntime.evalInitExprObjectArray(t, st, velem, vlen);
+				}
+				initExprCacheObject[init] = obj;
+				return obj;
+			}
+			FixedArray(t, vals) => {
+				var decl = t.array;
+				var st = decl.elem_types[0];
+				var obj: Object;
+				if (ObjReps.arrayMode == ArrayMode.Original) {
+					obj = HeapArrayValue.new(t.array, Arrays.map(vals, evalInitExpr));
+				} else {
+					obj = ObjectRuntime.evalInitExprObjectFixedArray(this, t, st, vals);
+				}
+				initExprCacheObject[init] = obj;
+				return obj;
+			}
+			Struct(t, vals) => {
+				var vvals = Arrays.map(vals, evalInitExpr);
+				var obj: Object;
+				if (ObjReps.structMode == StructMode.Original) {
+					obj = HeapStructValue.new(t.sdecl, vvals);
+				} else {
+					obj = ObjectRuntime.evalInitExprObjectStruct(t, vvals);
+				}
+				initExprCacheObject[init] = obj;
+				return obj;
+			}
+			ArrayNewData(t, data_index, offset, len) => {
+				var voffset = evalInitExpr(offset);
+				var vlen = evalInitExpr(len);
+				return null;  // TODO
+			}
+			ArrayNewElem(t, elem_index, offset, len) => {
+				var voffset = evalInitExpr(offset);
+				var vlen = evalInitExpr(len);
+				return null;  // TODO
+			}
+			_ => return null;
+		}
+	}
+	def evalInitExprScalar<T>(init: InitExpr) -> T {
+		match (init) {
+			I32(val) => return T.!(u32.view(val));
+			I64(val) => return T.!(u64.view(val));
+			F32(val) => return T.!(val);
+			F64(val) => return T.!(val);
+			V128(low, high) => return T.!((low, high));
+			Global(global_index, g) => {
+				return Values.unbox<T>(globals[global_index].get());
+			}
+			Const(val) => return Values.unbox<T>(val);
+			I31(val) => {
+				var v = evalInitExpr(val);
+				return T.!(u31.view(Values.unbox_i(v)));
+			}
+			I32_ADD(a, b) => return T.!(Values.unbox_u(evalInitExpr(a)) + Values.unbox_u(evalInitExpr(b)));
+			I32_SUB(a, b) => return T.!(Values.unbox_u(evalInitExpr(a)) - Values.unbox_u(evalInitExpr(b)));
+			I32_MUL(a, b) => return T.!(Values.unbox_u(evalInitExpr(a)) * Values.unbox_u(evalInitExpr(b)));
+			I64_ADD(a, b) => return T.!(Values.unbox_w(evalInitExpr(a)) + Values.unbox_w(evalInitExpr(b)));
+			I64_SUB(a, b) => return T.!(Values.unbox_w(evalInitExpr(a)) - Values.unbox_w(evalInitExpr(b)));
+			I64_MUL(a, b) => return T.!(Values.unbox_w(evalInitExpr(a)) * Values.unbox_w(evalInitExpr(b)));
+			_ => return T.!(0);
+		}
+	}
 	def findExportOfType<T>(matcher: GlobMatcher) -> T {
 		var decls = module.exports;
 		for (i < decls.length) {