Merged 7fe4d93

[interpreter] Don't assume generator functions do an initial yield.

R=hablich@chromium.org
NOTRY=true
NOPRESUBMIT=true
BUG=chromium:638019

Review-Url: https://codereview.chromium.org/2251003003
Cr-Commit-Position: refs/branch-heads/5.3@{#50}
Cr-Branched-From: 820a23a-refs/heads/5.3.332@{#2}
Cr-Branched-From: 37538cb-refs/heads/master@{#37308}

src/interpreter/bytecode-generator.cc

@@ -696,7 +696,10 @@ void BytecodeGenerator::VisitGeneratorPrologue() {
   BuildIndexedJump(generator_state_, 0, generator_resume_points_.size(),
                    generator_resume_points_);
 
-  builder()->Bind(&regular_call);
+  builder()
+      ->Bind(&regular_call)
+      .LoadLiteral(Smi::FromInt(JSGeneratorObject::kGeneratorExecuting))
+      .StoreAccumulatorInRegister(generator_state_);
   // This is a regular call. Fall through to the ordinary function prologue,
   // after which we will run into the generator object creation and other extra
   // code inserted by the parser.

test/cctest/interpreter/bytecode_expectations/Generators.golden

@@ -16,18 +16,20 @@ snippet: "
 "
 frame size: 11
 parameter count: 1
-bytecode array length: 200
+bytecode array length: 204
 bytecodes: [
                 B(Ldar), R(new_target),
                 B(JumpIfUndefined), U8(20),
                 B(ResumeGenerator), R(new_target),
                 B(Star), R(1),
                 B(LdaZero),
                 B(TestEqualStrict), R(1),
-                B(JumpIfTrue), U8(56),
+                B(JumpIfTrue), U8(60),
                 B(LdaSmi), U8(76),
                 B(Star), R(2),
                 B(CallRuntime), U16(Runtime::kAbort), R(2), U8(1),
+                B(LdaSmi), U8(-2),
+                B(Star), R(1),
                 B(CallRuntime), U16(Runtime::kNewFunctionContext), R(closure), U8(1),
                 B(PushContext), R(0),
                 B(Ldar), R(this),
@@ -109,7 +111,7 @@ bytecodes: [
 constant pool: [
 ]
 handlers: [
-  [38, 137, 143],
+  [42, 141, 147],
 ]
 
 ---
@@ -119,21 +121,23 @@ snippet: "
 "
 frame size: 11
 parameter count: 1
-bytecode array length: 293
+bytecode array length: 297
 bytecodes: [
                 B(Ldar), R(new_target),
                 B(JumpIfUndefined), U8(26),
                 B(ResumeGenerator), R(new_target),
                 B(Star), R(1),
                 B(LdaZero),
                 B(TestEqualStrict), R(1),
-                B(JumpIfTrue), U8(62),
+                B(JumpIfTrue), U8(66),
                 B(LdaSmi), U8(1),
                 B(TestEqualStrict), R(1),
                 B(JumpIfTrueConstant), U8(0),
                 B(LdaSmi), U8(76),
                 B(Star), R(2),
                 B(CallRuntime), U16(Runtime::kAbort), R(2), U8(1),
+                B(LdaSmi), U8(-2),
+                B(Star), R(1),
                 B(CallRuntime), U16(Runtime::kNewFunctionContext), R(closure), U8(1),
                 B(PushContext), R(0),
                 B(Ldar), R(this),
@@ -255,7 +259,7 @@ constant pool: [
   kInstanceTypeDontCare,
 ]
 handlers: [
-  [44, 221, 227],
+  [48, 225, 231],
 ]
 
 ---
@@ -265,21 +269,23 @@ snippet: "
 "
 frame size: 17
 parameter count: 1
-bytecode array length: 775
+bytecode array length: 779
 bytecodes: [
                 B(Ldar), R(new_target),
                 B(JumpIfUndefined), U8(26),
                 B(ResumeGenerator), R(new_target),
                 B(Star), R(3),
                 B(LdaZero),
                 B(TestEqualStrict), R(3),
-                B(JumpIfTrue), U8(62),
+                B(JumpIfTrue), U8(66),
                 B(LdaSmi), U8(1),
                 B(TestEqualStrict), R(3),
                 B(JumpIfTrueConstant), U8(3),
                 B(LdaSmi), U8(76),
                 B(Star), R(4),
                 B(CallRuntime), U16(Runtime::kAbort), R(4), U8(1),
+                B(LdaSmi), U8(-2),
+                B(Star), R(3),
                 B(CallRuntime), U16(Runtime::kNewFunctionContext), R(closure), U8(1),
                 B(PushContext), R(0),
                 B(Ldar), R(this),
@@ -601,9 +607,9 @@ constant pool: [
   kInstanceTypeDontCare,
 ]
 handlers: [
-  [44, 694, 700],
-  [154, 448, 454],
-  [157, 402, 404],
-  [551, 563, 565],
+  [48, 698, 704],
+  [158, 452, 458],
+  [161, 406, 408],
+  [555, 567, 569],
 ]
 

test/mjsunit/harmony/async-await-basic.js

@@ -360,3 +360,10 @@ assertEqualsAsync(
     "20", () => (async(foo, { a = "0" }) => foo + a)("2", { a: undefined }));
 assertThrows(() => eval("async({ foo = 1 })"), SyntaxError);
 assertThrows(() => eval("async(a, { foo = 1 })"), SyntaxError);
+
+// https://bugs.chromium.org/p/chromium/issues/detail?id=638019
+async function gaga() {
+  let i = 1;
+  while (i-- > 0) { await 42 }
+}
+assertDoesNotThrow(gaga);