diff --git a/src/compiler/factory/emitHelpers.ts b/src/compiler/factory/emitHelpers.ts
index 85a12581965..36063fadd55 100644
--- a/src/compiler/factory/emitHelpers.ts
+++ b/src/compiler/factory/emitHelpers.ts
@@ -705,6 +705,8 @@ namespace ts {
     //          - The verb (`next`, `throw`, or `return` method) to delegate to the expression
     //            of a `yield*`.
     //          - The result of evaluating the verb delegated to the expression of a `yield*`.
+    //  g       A temporary variable that holds onto the generator object until the generator
+    //          is started, allowing it to also act as the `suspendedStart` state.
     //
     // functions:
     //  verb(n)     Creates a bound callback to the `step` function for opcode `n`.
@@ -750,7 +752,7 @@ namespace ts {
                 function verb(n) { return function (v) { return step([n, v]); }; }
                 function step(op) {
                     if (f) throw new TypeError("Generator is already executing.");
-                    while (_) try {
+                    while (g && (g = 0, op[0] && (_ = 0)), _) try {
                         if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
                         if (y = 0, t) op = [op[0] & 2, t.value];
                         switch (op[0]) {
diff --git a/src/testRunner/tsconfig.json b/src/testRunner/tsconfig.json
index 0f7ee625094..2e930a68ef2 100644
--- a/src/testRunner/tsconfig.json
+++ b/src/testRunner/tsconfig.json
@@ -96,6 +96,7 @@
         "unittests/evaluation/externalModules.ts",
         "unittests/evaluation/forAwaitOf.ts",
         "unittests/evaluation/forOf.ts",
+        "unittests/evaluation/generator.ts",
         "unittests/evaluation/optionalCall.ts",
         "unittests/evaluation/objectRest.ts",
         "unittests/evaluation/superInStaticInitializer.ts",
diff --git a/src/testRunner/unittests/evaluation/generator.ts b/src/testRunner/unittests/evaluation/generator.ts
new file mode 100644
index 00000000000..e97dff75dde
--- /dev/null
+++ b/src/testRunner/unittests/evaluation/generator.ts
@@ -0,0 +1,33 @@
+describe("unittests:: evaluation:: generatorEvaluation", () => {
+    it("throw before start (es5)", () => {
+        const { gen, output } = evaluator.evaluateTypeScript(`
+            export const output: string[] = [];
+            export function * gen() {
+                output.push("start");
+                yield 1;
+                output.push("end");
+            }
+        `, { target: ts.ScriptTarget.ES5 });
+
+        const g = gen();
+        const e = new Error();
+        assert.throws(() => g.throw(e), e);
+        assert.deepEqual(g.next(), { value: undefined, done: true });
+        assert.deepEqual(output, []);
+    });
+    it("return before start (es5)", () => {
+        const { gen, output } = evaluator.evaluateTypeScript(`
+            export const output: string[] = [];
+            export function * gen() {
+                output.push("start");
+                yield 1;
+                output.push("end");
+            }
+        `, { target: ts.ScriptTarget.ES5 });
+
+        const g = gen();
+        assert.deepEqual(g.return(2), { value: 2, done: true });
+        assert.deepEqual(g.next(), { value: undefined, done: true });
+        assert.deepEqual(output, []);
+    });
+});
diff --git a/tests/baselines/reference/asyncArrowFunction11_es5.js b/tests/baselines/reference/asyncArrowFunction11_es5.js
index a16ce36e840..a9d236abf5a 100644
--- a/tests/baselines/reference/asyncArrowFunction11_es5.js
+++ b/tests/baselines/reference/asyncArrowFunction11_es5.js
@@ -23,7 +23,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncAwaitIsolatedModules_es5.js b/tests/baselines/reference/asyncAwaitIsolatedModules_es5.js
index ec3837911de..669af6e09ee 100644
--- a/tests/baselines/reference/asyncAwaitIsolatedModules_es5.js
+++ b/tests/baselines/reference/asyncAwaitIsolatedModules_es5.js
@@ -56,7 +56,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncAwait_es5.js b/tests/baselines/reference/asyncAwait_es5.js
index 6a6433e85c6..0be5df06a9d 100644
--- a/tests/baselines/reference/asyncAwait_es5.js
+++ b/tests/baselines/reference/asyncAwait_es5.js
@@ -62,7 +62,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncFunctionNoReturnType.js b/tests/baselines/reference/asyncFunctionNoReturnType.js
index 430210cbdbc..6a17af94903 100644
--- a/tests/baselines/reference/asyncFunctionNoReturnType.js
+++ b/tests/baselines/reference/asyncFunctionNoReturnType.js
@@ -21,7 +21,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncFunctionReturnExpressionErrorSpans.js b/tests/baselines/reference/asyncFunctionReturnExpressionErrorSpans.js
index 887484e933a..ac72fcd05fe 100644
--- a/tests/baselines/reference/asyncFunctionReturnExpressionErrorSpans.js
+++ b/tests/baselines/reference/asyncFunctionReturnExpressionErrorSpans.js
@@ -37,7 +37,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncFunctionTempVariableScoping.js b/tests/baselines/reference/asyncFunctionTempVariableScoping.js
index 3a6da56c993..9b8b83f93ee 100644
--- a/tests/baselines/reference/asyncFunctionTempVariableScoping.js
+++ b/tests/baselines/reference/asyncFunctionTempVariableScoping.js
@@ -20,7 +20,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncFunctionWithForStatementNoInitializer.js b/tests/baselines/reference/asyncFunctionWithForStatementNoInitializer.js
index 055a751f523..1ea24341d04 100644
--- a/tests/baselines/reference/asyncFunctionWithForStatementNoInitializer.js
+++ b/tests/baselines/reference/asyncFunctionWithForStatementNoInitializer.js
@@ -40,7 +40,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncImportNestedYield.js b/tests/baselines/reference/asyncImportNestedYield.js
index a9d64fbd3fa..190d930a1ad 100644
--- a/tests/baselines/reference/asyncImportNestedYield.js
+++ b/tests/baselines/reference/asyncImportNestedYield.js
@@ -10,7 +10,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncImportedPromise_es5.js b/tests/baselines/reference/asyncImportedPromise_es5.js
index 79a1ea3f13f..aaaf4a95491 100644
--- a/tests/baselines/reference/asyncImportedPromise_es5.js
+++ b/tests/baselines/reference/asyncImportedPromise_es5.js
@@ -53,7 +53,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/asyncMultiFile_es5.js b/tests/baselines/reference/asyncMultiFile_es5.js
index 392a4456cc2..2dd73b8b6c7 100644
--- a/tests/baselines/reference/asyncMultiFile_es5.js
+++ b/tests/baselines/reference/asyncMultiFile_es5.js
@@ -21,7 +21,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/blockScopedBindingsInDownlevelGenerator.js b/tests/baselines/reference/blockScopedBindingsInDownlevelGenerator.js
index eb59846f9e0..5298d7c054b 100644
--- a/tests/baselines/reference/blockScopedBindingsInDownlevelGenerator.js
+++ b/tests/baselines/reference/blockScopedBindingsInDownlevelGenerator.js
@@ -13,7 +13,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/castOfYield.js b/tests/baselines/reference/castOfYield.js
index 86d35bedad4..0af321306cd 100644
--- a/tests/baselines/reference/castOfYield.js
+++ b/tests/baselines/reference/castOfYield.js
@@ -13,7 +13,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/checkJsxSubtleSkipContextSensitiveBug.js b/tests/baselines/reference/checkJsxSubtleSkipContextSensitiveBug.js
index 2b3e3d3f0ab..a05c9da890b 100644
--- a/tests/baselines/reference/checkJsxSubtleSkipContextSensitiveBug.js
+++ b/tests/baselines/reference/checkJsxSubtleSkipContextSensitiveBug.js
@@ -56,7 +56,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/classStaticBlock6.js b/tests/baselines/reference/classStaticBlock6.js
index 69d14640789..d0440849630 100644
--- a/tests/baselines/reference/classStaticBlock6.js
+++ b/tests/baselines/reference/classStaticBlock6.js
@@ -94,7 +94,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/classStaticBlock7.js b/tests/baselines/reference/classStaticBlock7.js
index fd198db1871..f0d2fe31eef 100644
--- a/tests/baselines/reference/classStaticBlock7.js
+++ b/tests/baselines/reference/classStaticBlock7.js
@@ -60,7 +60,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/contextualReturnTypeOfIIFE.js b/tests/baselines/reference/contextualReturnTypeOfIIFE.js
index a742ee232fb..65ebbe6f83e 100644
--- a/tests/baselines/reference/contextualReturnTypeOfIIFE.js
+++ b/tests/baselines/reference/contextualReturnTypeOfIIFE.js
@@ -28,7 +28,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/controlFlowForCatchAndFinally.js b/tests/baselines/reference/controlFlowForCatchAndFinally.js
index 48075ffb6b4..030242954aa 100644
--- a/tests/baselines/reference/controlFlowForCatchAndFinally.js
+++ b/tests/baselines/reference/controlFlowForCatchAndFinally.js
@@ -57,7 +57,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/correctOrderOfPromiseMethod.js b/tests/baselines/reference/correctOrderOfPromiseMethod.js
index 81a91ba06fd..5cfa948d9bf 100644
--- a/tests/baselines/reference/correctOrderOfPromiseMethod.js
+++ b/tests/baselines/reference/correctOrderOfPromiseMethod.js
@@ -46,7 +46,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/declarationEmitPrivateAsync.js b/tests/baselines/reference/declarationEmitPrivateAsync.js
index f10376c24b0..0ac83048dd2 100644
--- a/tests/baselines/reference/declarationEmitPrivateAsync.js
+++ b/tests/baselines/reference/declarationEmitPrivateAsync.js
@@ -22,7 +22,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/destructureOfVariableSameAsShorthand.js b/tests/baselines/reference/destructureOfVariableSameAsShorthand.js
index 2adf58de84b..e73c3f26792 100644
--- a/tests/baselines/reference/destructureOfVariableSameAsShorthand.js
+++ b/tests/baselines/reference/destructureOfVariableSameAsShorthand.js
@@ -42,7 +42,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/destructuringControlFlowNoCrash.js b/tests/baselines/reference/destructuringControlFlowNoCrash.js
index 0b7de9ee8e4..449ff0aaacb 100644
--- a/tests/baselines/reference/destructuringControlFlowNoCrash.js
+++ b/tests/baselines/reference/destructuringControlFlowNoCrash.js
@@ -33,7 +33,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/doNotElaborateAssignabilityToTypeParameters.js b/tests/baselines/reference/doNotElaborateAssignabilityToTypeParameters.js
index 8bb622be4f5..5628b4fe0d2 100644
--- a/tests/baselines/reference/doNotElaborateAssignabilityToTypeParameters.js
+++ b/tests/baselines/reference/doNotElaborateAssignabilityToTypeParameters.js
@@ -28,7 +28,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js b/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js
index 0cafc5a2d88..0ecd6008916 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.classMethods.es5.js
@@ -67,7 +67,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -119,7 +119,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -178,7 +178,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -237,7 +237,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -319,7 +319,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -409,7 +409,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -467,7 +467,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -522,7 +522,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -592,7 +592,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js b/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js
index ba9e6b4180e..40fd03ca101 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.functionDeclarations.es5.js
@@ -36,7 +36,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -83,7 +83,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -137,7 +137,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -191,7 +191,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -268,7 +268,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -353,7 +353,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -406,7 +406,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js b/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js
index bd1280df237..e671326c3d3 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.functionExpressions.es5.js
@@ -36,7 +36,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -83,7 +83,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -137,7 +137,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -191,7 +191,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -268,7 +268,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -353,7 +353,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -406,7 +406,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js b/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js
index 138c729aa29..a3f89f6d244 100644
--- a/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js
+++ b/tests/baselines/reference/emitter.asyncGenerators.objectLiteralMethods.es5.js
@@ -50,7 +50,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -99,7 +99,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -155,7 +155,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -211,7 +211,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -290,7 +290,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -377,7 +377,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -432,7 +432,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/emitter.forAwait(target=es5).js b/tests/baselines/reference/emitter.forAwait(target=es5).js
index 5b182d16d5c..671c81d2dea 100644
--- a/tests/baselines/reference/emitter.forAwait(target=es5).js
+++ b/tests/baselines/reference/emitter.forAwait(target=es5).js
@@ -66,7 +66,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -148,7 +148,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -221,7 +221,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -306,7 +306,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -400,7 +400,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -474,7 +474,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -560,7 +560,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/es5-asyncFunction.js b/tests/baselines/reference/es5-asyncFunction.js
index 805e4d4a4c7..cea62e7a1b9 100644
--- a/tests/baselines/reference/es5-asyncFunction.js
+++ b/tests/baselines/reference/es5-asyncFunction.js
@@ -24,7 +24,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/es5-asyncFunctionLongObjectLiteral.js b/tests/baselines/reference/es5-asyncFunctionLongObjectLiteral.js
index 06370f1a0d7..7deffab18ad 100644
--- a/tests/baselines/reference/es5-asyncFunctionLongObjectLiteral.js
+++ b/tests/baselines/reference/es5-asyncFunctionLongObjectLiteral.js
@@ -44,7 +44,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/es5-importHelpersAsyncFunctions.js b/tests/baselines/reference/es5-importHelpersAsyncFunctions.js
index 781027fc18a..66e610086b2 100644
--- a/tests/baselines/reference/es5-importHelpersAsyncFunctions.js
+++ b/tests/baselines/reference/es5-importHelpersAsyncFunctions.js
@@ -46,7 +46,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/exportDefaultFunctionInNamespace.js b/tests/baselines/reference/exportDefaultFunctionInNamespace.js
index 482611413b7..92795aaae6c 100644
--- a/tests/baselines/reference/exportDefaultFunctionInNamespace.js
+++ b/tests/baselines/reference/exportDefaultFunctionInNamespace.js
@@ -24,7 +24,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/expressionsForbiddenInParameterInitializers.js b/tests/baselines/reference/expressionsForbiddenInParameterInitializers.js
index fc389fc91b1..63daa63dfd2 100644
--- a/tests/baselines/reference/expressionsForbiddenInParameterInitializers.js
+++ b/tests/baselines/reference/expressionsForbiddenInParameterInitializers.js
@@ -23,7 +23,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/forAwaitPerIterationBindingDownlevel.js b/tests/baselines/reference/forAwaitPerIterationBindingDownlevel.js
index e23c0705846..0abf0040006 100644
--- a/tests/baselines/reference/forAwaitPerIterationBindingDownlevel.js
+++ b/tests/baselines/reference/forAwaitPerIterationBindingDownlevel.js
@@ -40,7 +40,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES3AMD.js b/tests/baselines/reference/importCallExpressionAsyncES3AMD.js
index e40e9ffbd62..c4d58cd0805 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES3AMD.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES3AMD.js
@@ -44,7 +44,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES3CJS.js b/tests/baselines/reference/importCallExpressionAsyncES3CJS.js
index 9dc9b34b1e1..777f8fc651c 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES3CJS.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES3CJS.js
@@ -45,7 +45,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES3System.js b/tests/baselines/reference/importCallExpressionAsyncES3System.js
index e4cc24387bc..2c4fa8bb5cc 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES3System.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES3System.js
@@ -46,7 +46,7 @@ System.register([], function (exports_1, context_1) {
         function verb(n) { return function (v) { return step([n, v]); }; }
         function step(op) {
             if (f) throw new TypeError("Generator is already executing.");
-            while (_) try {
+            while (g && (g = 0, op[0] && (_ = 0)), _) try {
                 if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
                 if (y = 0, t) op = [op[0] & 2, t.value];
                 switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES3UMD.js b/tests/baselines/reference/importCallExpressionAsyncES3UMD.js
index e679da93b59..f6ebad67764 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES3UMD.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES3UMD.js
@@ -44,7 +44,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES5AMD.js b/tests/baselines/reference/importCallExpressionAsyncES5AMD.js
index 00bc55b4389..696b44e012e 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES5AMD.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES5AMD.js
@@ -44,7 +44,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES5CJS.js b/tests/baselines/reference/importCallExpressionAsyncES5CJS.js
index 1f95edc3aaf..59bb76e9ac2 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES5CJS.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES5CJS.js
@@ -45,7 +45,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES5System.js b/tests/baselines/reference/importCallExpressionAsyncES5System.js
index bc577e5c981..a7e9ef33ee0 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES5System.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES5System.js
@@ -46,7 +46,7 @@ System.register([], function (exports_1, context_1) {
         function verb(n) { return function (v) { return step([n, v]); }; }
         function step(op) {
             if (f) throw new TypeError("Generator is already executing.");
-            while (_) try {
+            while (g && (g = 0, op[0] && (_ = 0)), _) try {
                 if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
                 if (y = 0, t) op = [op[0] & 2, t.value];
                 switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionAsyncES5UMD.js b/tests/baselines/reference/importCallExpressionAsyncES5UMD.js
index c960312db29..893a1ebb6d3 100644
--- a/tests/baselines/reference/importCallExpressionAsyncES5UMD.js
+++ b/tests/baselines/reference/importCallExpressionAsyncES5UMD.js
@@ -44,7 +44,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionNestedAMD2.js b/tests/baselines/reference/importCallExpressionNestedAMD2.js
index ffc42963975..3200a5831d9 100644
--- a/tests/baselines/reference/importCallExpressionNestedAMD2.js
+++ b/tests/baselines/reference/importCallExpressionNestedAMD2.js
@@ -30,7 +30,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionNestedCJS2.js b/tests/baselines/reference/importCallExpressionNestedCJS2.js
index b4dc9745b41..a29cbe396f1 100644
--- a/tests/baselines/reference/importCallExpressionNestedCJS2.js
+++ b/tests/baselines/reference/importCallExpressionNestedCJS2.js
@@ -28,7 +28,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionNestedES20152.js b/tests/baselines/reference/importCallExpressionNestedES20152.js
index c0b888df2fb..7d52515fd23 100644
--- a/tests/baselines/reference/importCallExpressionNestedES20152.js
+++ b/tests/baselines/reference/importCallExpressionNestedES20152.js
@@ -26,7 +26,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionNestedES20202.js b/tests/baselines/reference/importCallExpressionNestedES20202.js
index 3c47766522a..619b9b105a5 100644
--- a/tests/baselines/reference/importCallExpressionNestedES20202.js
+++ b/tests/baselines/reference/importCallExpressionNestedES20202.js
@@ -27,7 +27,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionNestedSystem2.js b/tests/baselines/reference/importCallExpressionNestedSystem2.js
index 60861b7aca7..62dc40ce6ac 100644
--- a/tests/baselines/reference/importCallExpressionNestedSystem2.js
+++ b/tests/baselines/reference/importCallExpressionNestedSystem2.js
@@ -36,7 +36,7 @@ System.register([], function (exports_1, context_1) {
         function verb(n) { return function (v) { return step([n, v]); }; }
         function step(op) {
             if (f) throw new TypeError("Generator is already executing.");
-            while (_) try {
+            while (g && (g = 0, op[0] && (_ = 0)), _) try {
                 if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
                 if (y = 0, t) op = [op[0] & 2, t.value];
                 switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionNestedUMD2.js b/tests/baselines/reference/importCallExpressionNestedUMD2.js
index 33d3d608e14..812cf0aa1c6 100644
--- a/tests/baselines/reference/importCallExpressionNestedUMD2.js
+++ b/tests/baselines/reference/importCallExpressionNestedUMD2.js
@@ -38,7 +38,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importCallExpressionNoModuleKindSpecified.js b/tests/baselines/reference/importCallExpressionNoModuleKindSpecified.js
index 708025a5d3a..3029a6b53f2 100644
--- a/tests/baselines/reference/importCallExpressionNoModuleKindSpecified.js
+++ b/tests/baselines/reference/importCallExpressionNoModuleKindSpecified.js
@@ -61,7 +61,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importMeta(module=commonjs,target=es5).js b/tests/baselines/reference/importMeta(module=commonjs,target=es5).js
index c6bc5cf86f3..f2728bb75ae 100644
--- a/tests/baselines/reference/importMeta(module=commonjs,target=es5).js
+++ b/tests/baselines/reference/importMeta(module=commonjs,target=es5).js
@@ -55,7 +55,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importMeta(module=es2020,target=es5).js b/tests/baselines/reference/importMeta(module=es2020,target=es5).js
index 724ad5b3aca..7cdf12ba8fe 100644
--- a/tests/baselines/reference/importMeta(module=es2020,target=es5).js
+++ b/tests/baselines/reference/importMeta(module=es2020,target=es5).js
@@ -54,7 +54,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importMeta(module=esnext,target=es5).js b/tests/baselines/reference/importMeta(module=esnext,target=es5).js
index 724ad5b3aca..7cdf12ba8fe 100644
--- a/tests/baselines/reference/importMeta(module=esnext,target=es5).js
+++ b/tests/baselines/reference/importMeta(module=esnext,target=es5).js
@@ -54,7 +54,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/importMeta(module=system,target=es5).js b/tests/baselines/reference/importMeta(module=system,target=es5).js
index e68407acd99..2be9428dee7 100644
--- a/tests/baselines/reference/importMeta(module=system,target=es5).js
+++ b/tests/baselines/reference/importMeta(module=system,target=es5).js
@@ -56,7 +56,7 @@ System.register([], function (exports_1, context_1) {
         function verb(n) { return function (v) { return step([n, v]); }; }
         function step(op) {
             if (f) throw new TypeError("Generator is already executing.");
-            while (_) try {
+            while (g && (g = 0, op[0] && (_ = 0)), _) try {
                 if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
                 if (y = 0, t) op = [op[0] & 2, t.value];
                 switch (op[0]) {
diff --git a/tests/baselines/reference/invalidContinueInDownlevelAsync.js b/tests/baselines/reference/invalidContinueInDownlevelAsync.js
index 9a2fc08f4a8..827cbcfaf5a 100644
--- a/tests/baselines/reference/invalidContinueInDownlevelAsync.js
+++ b/tests/baselines/reference/invalidContinueInDownlevelAsync.js
@@ -24,7 +24,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/jsFileCompilationAwaitModifier.js b/tests/baselines/reference/jsFileCompilationAwaitModifier.js
index 9cc51eb2bbb..e013276a003 100644
--- a/tests/baselines/reference/jsFileCompilationAwaitModifier.js
+++ b/tests/baselines/reference/jsFileCompilationAwaitModifier.js
@@ -26,7 +26,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/labeledStatementWithLabel.js b/tests/baselines/reference/labeledStatementWithLabel.js
index 470abce502c..c70c94f8fef 100644
--- a/tests/baselines/reference/labeledStatementWithLabel.js
+++ b/tests/baselines/reference/labeledStatementWithLabel.js
@@ -30,7 +30,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/legacyNodeModulesExportsSpecifierGenerationConditions.js b/tests/baselines/reference/legacyNodeModulesExportsSpecifierGenerationConditions.js
index a4d9ac6d90b..964e9069815 100644
--- a/tests/baselines/reference/legacyNodeModulesExportsSpecifierGenerationConditions.js
+++ b/tests/baselines/reference/legacyNodeModulesExportsSpecifierGenerationConditions.js
@@ -48,7 +48,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/neverAsDiscriminantType(strict=false).js b/tests/baselines/reference/neverAsDiscriminantType(strict=false).js
index de1a5790cce..adfa34faec1 100644
--- a/tests/baselines/reference/neverAsDiscriminantType(strict=false).js
+++ b/tests/baselines/reference/neverAsDiscriminantType(strict=false).js
@@ -82,7 +82,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/neverAsDiscriminantType(strict=true).js b/tests/baselines/reference/neverAsDiscriminantType(strict=true).js
index de1a5790cce..adfa34faec1 100644
--- a/tests/baselines/reference/neverAsDiscriminantType(strict=true).js
+++ b/tests/baselines/reference/neverAsDiscriminantType(strict=true).js
@@ -82,7 +82,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/operationsAvailableOnPromisedType.js b/tests/baselines/reference/operationsAvailableOnPromisedType.js
index 3fca9b4e785..139a61c0c7d 100644
--- a/tests/baselines/reference/operationsAvailableOnPromisedType.js
+++ b/tests/baselines/reference/operationsAvailableOnPromisedType.js
@@ -45,7 +45,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/parenthesizedAsyncArrowFunction.js b/tests/baselines/reference/parenthesizedAsyncArrowFunction.js
index 916a0e4a045..f3ad4f02eef 100644
--- a/tests/baselines/reference/parenthesizedAsyncArrowFunction.js
+++ b/tests/baselines/reference/parenthesizedAsyncArrowFunction.js
@@ -21,7 +21,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/promiseDefinitionTest.js b/tests/baselines/reference/promiseDefinitionTest.js
index c502085e362..e732580b018 100644
--- a/tests/baselines/reference/promiseDefinitionTest.js
+++ b/tests/baselines/reference/promiseDefinitionTest.js
@@ -20,7 +20,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/reactReduxLikeDeferredInferenceAllowsAssignment.js b/tests/baselines/reference/reactReduxLikeDeferredInferenceAllowsAssignment.js
index 5f1deaf76fe..05178f13a9e 100644
--- a/tests/baselines/reference/reactReduxLikeDeferredInferenceAllowsAssignment.js
+++ b/tests/baselines/reference/reactReduxLikeDeferredInferenceAllowsAssignment.js
@@ -179,7 +179,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/spreadOfParamsFromGeneratorMakesRequiredParams.js b/tests/baselines/reference/spreadOfParamsFromGeneratorMakesRequiredParams.js
index f1bcf13697d..4ceb7af6f03 100644
--- a/tests/baselines/reference/spreadOfParamsFromGeneratorMakesRequiredParams.js
+++ b/tests/baselines/reference/spreadOfParamsFromGeneratorMakesRequiredParams.js
@@ -13,7 +13,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/templateStringWithEmbeddedYieldKeyword.js b/tests/baselines/reference/templateStringWithEmbeddedYieldKeyword.js
index a3a1bdcc504..d9581fc3dd4 100644
--- a/tests/baselines/reference/templateStringWithEmbeddedYieldKeyword.js
+++ b/tests/baselines/reference/templateStringWithEmbeddedYieldKeyword.js
@@ -12,7 +12,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
diff --git a/tests/baselines/reference/transformNestedGeneratorsWithTry.js b/tests/baselines/reference/transformNestedGeneratorsWithTry.js
index 84b933cc6a7..fafab23513f 100644
--- a/tests/baselines/reference/transformNestedGeneratorsWithTry.js
+++ b/tests/baselines/reference/transformNestedGeneratorsWithTry.js
@@ -39,7 +39,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {