Fixed review comments

aneeshdk · aneeshdk · commit 5e2687804014 · 2016-08-18T14:58:12.000-07:00
diff --git a/lib/Backend/BailOut.cpp b/lib/Backend/BailOut.cpp
@@ -1437,7 +1437,7 @@ BailOutRecord::BailOutHelper(Js::JavascriptCallStackLayout * layout, Js::ScriptF
     Js::InterpreterStackFrame* newInstance = nullptr;
     Js::Var* allocation = nullptr;
 
-    if (executeFunction->IsGenerator() || executeFunction->IsAsync())
+    if (executeFunction->IsCoroutine())
     {
         // If the FunctionBody is a generator then this call is being made by one of the three
         // generator resuming methods: next(), throw(), or return().  They all pass the generator
diff --git a/lib/Backend/FlowGraph.cpp b/lib/Backend/FlowGraph.cpp
@@ -1099,7 +1099,7 @@ FlowGraph::Destroy(void)
                 // Skipping Try blocks as we have dependency on blocks to get the last instr(see below in this function)
                 if (!fHasTry)
                 {
-                    if (this->func->GetJnFunction()->IsGenerator() || this->func->GetJnFunction()->IsAsync())
+                    if (this->func->GetJnFunction()->IsCoroutine())
                     {
                         // the label could be a yield resume label, in which case we also need to remove it from the YieldOffsetResumeLabels list
                         this->func->MapUntilYieldOffsetResumeLabels([this, &labelInstr](int i, const YieldOffsetResumeLabel& yorl)
diff --git a/lib/Backend/Func.cpp b/lib/Backend/Func.cpp
@@ -214,7 +214,7 @@ Func::Func(JitArenaAllocator *alloc, CodeGenWorkItem* workItem, const Js::Functi
         m_nonTempLocalVars = Anew(this->m_alloc, BVSparse<JitArenaAllocator>, this->m_alloc);
     }
 
-    if (this->m_jnFunction->IsGenerator() || this->m_jnFunction->IsAsync())
+    if (this->m_jnFunction->IsCoroutine())
     {
         m_yieldOffsetResumeLabelList = YieldOffsetResumeLabelList::New(this->m_alloc);
     }
@@ -846,8 +846,8 @@ Func::AjustLocalVarSlotOffset()
 bool
 Func::DoGlobOptsForGeneratorFunc()
 {
-    // Disable GlobOpt optimizations for generators and asyn functions initially. Will visit and enable each one by one.
-    return !m_jnFunction->IsGenerator() && !m_jnFunction->IsAsync();
+    // Disable GlobOpt optimizations for generators and async functions initially. Will visit and enable each one by one.
+    return !m_jnFunction->IsCoroutine();
 }
 
 void
diff --git a/lib/Backend/IRBuilder.cpp b/lib/Backend/IRBuilder.cpp
@@ -1365,7 +1365,7 @@ IRBuilder::BuildImplicitArgIns()
 void
 IRBuilder::BuildGeneratorPreamble()
 {
-    if (!this->m_func->GetJnFunction()->IsGenerator() && !this->m_func->GetJnFunction()->IsAsync())
+    if (!this->m_func->GetJnFunction()->IsCoroutine())
     {
         return;
     }
diff --git a/lib/Backend/Lower.cpp b/lib/Backend/Lower.cpp
@@ -5084,7 +5084,7 @@ Lowerer::LowerNewScObjArrayNoArg(IR::Instr *newObjInstr)
 void
 Lowerer::LowerPrologEpilog()
 {
-    if (m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync())
+    if (m_func->GetJnFunction()->IsCoroutine())
     {
         LowerGeneratorResumeJumpTable();
     }
@@ -5121,7 +5121,7 @@ Lowerer::LowerPrologEpilogAsmJs()
 void
 Lowerer::LowerGeneratorResumeJumpTable()
 {
-    Assert(m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync());
+    Assert(m_func->GetJnFunction()->IsCoroutine());
 
     IR::Instr * jumpTableInstr = m_func->m_headInstr;
     AssertMsg(jumpTableInstr->IsEntryInstr(), "First instr isn't an EntryInstr...");
@@ -7568,7 +7568,7 @@ Lowerer::LoadArgumentCount(IR::Instr *const instr)
         instr->SetSrc1(IR::IntConstOpnd::New(instr->m_func->actualCount, TyUint32, instr->m_func, true));
         LowererMD::ChangeToAssign(instr);
     }
-    else if (instr->m_func->GetJnFunction()->IsGenerator() || instr->m_func->GetJnFunction()->IsAsync())
+    else if (instr->m_func->GetJnFunction()->IsCoroutine())
     {
         IR::SymOpnd* symOpnd = LoadCallInfo(instr);
         instr->SetSrc1(symOpnd);
@@ -9607,7 +9607,7 @@ IR::Instr *Lowerer::LowerRestParameter(IR::Opnd *formalsOpnd, IR::Opnd *dstOpnd,
 
     LoadScriptContext(helperCallInstr);
 
-    BOOL isGenerator = this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync();
+    BOOL isGenerator = this->m_func->GetJnFunction()->IsCoroutine();
 
     // Elements pointer = ebp + (formals count + formals offset + 1)*sizeof(Var)
     IR::RegOpnd *srcOpnd = isGenerator ? generatorArgsPtrOpnd : IR::Opnd::CreateFramePointerOpnd(this->m_func);
@@ -9715,7 +9715,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)
             // $createRestArray
             instrArgIn->InsertBefore(createRestArrayLabel);
 
-            if (m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync())
+            if (m_func->GetJnFunction()->IsCoroutine())
             {
                 generatorArgsPtrOpnd = LoadGeneratorArgsPtr(instrArgIn);
             }
@@ -9734,7 +9734,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)
     if (argIndex == 1)
     {
         // The "this" argument is not source-dependent and doesn't need to be checked.
-        if (m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync())
+        if (m_func->GetJnFunction()->IsCoroutine())
         {
             generatorArgsPtrOpnd = LoadGeneratorArgsPtr(instrArgIn);
             ConvertArgOpndIfGeneratorFunction(instrArgIn, generatorArgsPtrOpnd);
@@ -9788,7 +9788,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)
 
     // Now insert all the checks and undef-assigns.
 
-    if (m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync())
+    if (m_func->GetJnFunction()->IsCoroutine())
     {
         generatorArgsPtrOpnd = LoadGeneratorArgsPtr(instrInsert);
     }
@@ -9958,7 +9958,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)
 void
 Lowerer::ConvertArgOpndIfGeneratorFunction(IR::Instr *instrArgIn, IR::RegOpnd *generatorArgsPtrOpnd)
 {
-    if (this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync())
+    if (this->m_func->GetJnFunction()->IsCoroutine())
     {
         // Replace stack param operand with offset into arguments array held by
         // the generator object.
@@ -10664,7 +10664,7 @@ Lowerer::LoadCallInfo(IR::Instr * instrInsert)
     IR::SymOpnd * srcOpnd;
     Func * func = instrInsert->m_func;
 
-    if (func->GetJnFunction()->IsGenerator() || func->GetJnFunction()->IsAsync())
+    if (func->GetJnFunction()->IsCoroutine())
     {
         // Generator function arguments and ArgumentsInfo are not on the stack.  Instead they
         // are accessed off the generator object (which is prm1).
@@ -18111,7 +18111,7 @@ IR::IndirOpnd*
 Lowerer::GetArgsIndirOpndForTopFunction(IR::Instr* ldElem, IR::Opnd* valueOpnd)
 {
     // Load argument set dst = [ebp + index] (or grab from the generator object if m_func is a generator function).
-    IR::RegOpnd *baseOpnd = (m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync()) ? LoadGeneratorArgsPtr(ldElem) : IR::Opnd::CreateFramePointerOpnd(m_func);
+    IR::RegOpnd *baseOpnd = m_func->GetJnFunction()->IsCoroutine() ? LoadGeneratorArgsPtr(ldElem) : IR::Opnd::CreateFramePointerOpnd(m_func);
     IR::IndirOpnd* argIndirOpnd = nullptr;
     // The stack looks like this:
     //       ...
@@ -18125,7 +18125,7 @@ Lowerer::GetArgsIndirOpndForTopFunction(IR::Instr* ldElem, IR::Opnd* valueOpnd)
 
     //actual arguments offset is LowererMD::GetFormalParamOffset() + 1 (this)
 
-    uint16 actualOffset = (m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync()) ? 1 : GetFormalParamOffset() + 1; //5
+    uint16 actualOffset = m_func->GetJnFunction()->IsCoroutine() ? 1 : GetFormalParamOffset() + 1; //5
     Assert(actualOffset == 5 || m_func->GetJnFunction()->IsGenerator());
     if (valueOpnd->IsIntConstOpnd())
     {
@@ -20366,7 +20366,7 @@ Lowerer::GenerateLoadNewTarget(IR::Instr* instrInsert)
 
     Assert(!func->IsInlinee());
 
-    if (func->GetJnFunction()->IsGenerator() || func->GetJnFunction()->IsAsync())
+    if (func->GetJnFunction()->IsCoroutine())
     {
         instrInsert->SetSrc1(opndUndefAddress);
         LowererMD::ChangeToAssign(instrInsert);
@@ -21101,7 +21101,7 @@ void Lowerer::GenerateNullOutGeneratorFrame(IR::Instr* insertInstr)
 
 void Lowerer::LowerFunctionExit(IR::Instr* funcExit)
 {
-    if (m_func->GetJnFunction()->IsGenerator() || m_func->GetJnFunction()->IsAsync())
+    if (m_func->GetJnFunction()->IsCoroutine())
     {
         GenerateNullOutGeneratorFrame(funcExit->m_prev);
     }
diff --git a/lib/Backend/amd64/LowererMDArch.cpp b/lib/Backend/amd64/LowererMDArch.cpp
@@ -140,7 +140,7 @@ LowererMDArch::Init(LowererMD *lowererMD)
 IR::Instr *
 LowererMDArch::LoadInputParamPtr(IR::Instr *instrInsert, IR::RegOpnd *optionalDstOpnd /* = nullptr */)
 {
-    if (this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync())
+    if (this->m_func->GetJnFunction()->IsCoroutine())
     {
         IR::RegOpnd * argPtrRegOpnd = Lowerer::LoadGeneratorArgsPtr(instrInsert);
         IR::IndirOpnd * indirOpnd = IR::IndirOpnd::New(argPtrRegOpnd, 1 * MachPtr, TyMachPtr, this->m_func);
@@ -380,7 +380,7 @@ LowererMDArch::LoadHeapArguments(IR::Instr *instrArgs, bool force /* = false */,
             this->m_func->SetArgOffset(paramSym, 2 * MachPtr);
             IR::Opnd * srcOpnd = IR::SymOpnd::New(paramSym, TyMachReg, func);
 
-            if (this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync())
+            if (this->m_func->GetJnFunction()->IsCoroutine())
             {
                 // the function object for generator calls is a GeneratorVirtualScriptFunction object
                 // and we need to pass the real JavascriptGeneratorFunction object so grab it instead
@@ -430,7 +430,7 @@ LowererMDArch::LoadFuncExpression(IR::Instr *instrFuncExpr)
         paramOpnd = IR::SymOpnd::New(paramSym, TyMachReg, this->m_func);
     }
 
-    if (instrFuncExpr->m_func->GetJnFunction()->IsGenerator() || instrFuncExpr->m_func->GetJnFunction()->IsAsync())
+    if (instrFuncExpr->m_func->GetJnFunction()->IsCoroutine())
     {
         // the function object for generator calls is a GeneratorVirtualScriptFunction object
         // and we need to return the real JavascriptGeneratorFunction object so grab it before
diff --git a/lib/Backend/arm/LowerMD.cpp b/lib/Backend/arm/LowerMD.cpp
@@ -1993,7 +1993,7 @@ LowererMD::Init(Lowerer *lowerer)
 IR::Instr *
 LowererMD::LoadInputParamPtr(IR::Instr * instrInsert, IR::RegOpnd * optionalDstOpnd /* = nullptr */)
 {
-    if (this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync())
+    if (this->m_func->GetJnFunction()->IsCoroutine())
     {
         IR::RegOpnd * argPtrRegOpnd = Lowerer::LoadGeneratorArgsPtr(instrInsert);
         IR::IndirOpnd * indirOpnd = IR::IndirOpnd::New(argPtrRegOpnd, 1 * MachPtr, TyMachPtr, this->m_func);
@@ -2087,7 +2087,7 @@ LowererMD::LoadStackArgPtr(IR::Instr * instr)
         instr->SetSrc1(tmpOpnd);
         instr->SetSrc2(IR::IntConstOpnd::New(sizeof(Js::Var), TyMachReg, this->m_func));
     }
-    else if (this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync())
+    else if (this->m_func->GetJnFunction()->IsCoroutine())
     {
         IR::Instr *instr2 = LoadInputParamPtr(instr, instr->UnlinkDst()->AsRegOpnd());
         instr->Remove();
diff --git a/lib/Backend/i386/LowererMDArch.cpp b/lib/Backend/i386/LowererMDArch.cpp
@@ -137,7 +137,7 @@ LowererMDArch::Init(LowererMD *lowererMD)
 IR::Instr *
 LowererMDArch::LoadInputParamPtr(IR::Instr *instrInsert, IR::RegOpnd *optionalDstOpnd /* = nullptr */)
 {
-    if (this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync())
+    if (this->m_func->GetJnFunction()->IsCoroutine())
     {
         IR::RegOpnd * argPtrRegOpnd = Lowerer::LoadGeneratorArgsPtr(instrInsert);
         IR::IndirOpnd * indirOpnd = IR::IndirOpnd::New(argPtrRegOpnd, 1 * MachPtr, TyMachPtr, this->m_func);
@@ -334,7 +334,7 @@ LowererMDArch::LoadHeapArguments(IR::Instr *instrArgs, bool force, IR::Opnd* opn
             this->m_func->SetArgOffset(paramSym, 2 * MachPtr);
             IR::Opnd *srcOpnd = IR::SymOpnd::New(paramSym, TyMachReg, func);
 
-            if (this->m_func->GetJnFunction()->IsGenerator() || this->m_func->GetJnFunction()->IsAsync())
+            if (this->m_func->GetJnFunction()->IsCoroutine())
             {
                 // the function object for generator calls is a GeneratorVirtualScriptFunction object
                 // and we need to pass the real JavascriptGeneratorFunction object so grab it instead
@@ -501,7 +501,7 @@ LowererMDArch::LoadFuncExpression(IR::Instr *instrFuncExpr)
         paramOpnd = IR::SymOpnd::New(paramSym, TyMachReg, func);
     }
 
-    if (instrFuncExpr->m_func->GetJnFunction()->IsGenerator() || instrFuncExpr->m_func->GetJnFunction()->IsAsync())
+    if (instrFuncExpr->m_func->GetJnFunction()->IsCoroutine())
     {
         // the function object for generator calls is a GeneratorVirtualScriptFunction object
         // and we need to return the real JavascriptGeneratorFunction object so grab it before
diff --git a/lib/Parser/ptree.h b/lib/Parser/ptree.h
@@ -338,6 +338,7 @@ struct PnFnc
     bool IsDeclaration() const { return HasFlags(kFunctionDeclaration); }
     bool IsGeneratedDefault() const { return HasFlags(kFunctionIsGeneratedDefault); }
     bool IsGenerator() const { return HasFlags(kFunctionIsGenerator); }
+    bool IsCoroutine() const { return HasFlags(kFunctionIsGenerator) || HasFlags(kFunctionIsAsync); }
     bool IsLambda() const { return HasFlags(kFunctionIsLambda); }
     bool IsMethod() const { return HasFlags(kFunctionIsMethod); }
     bool IsNested() const { return HasFlags(kFunctionNested); }
diff --git a/lib/Runtime/Base/FunctionBody.h b/lib/Runtime/Base/FunctionBody.h
@@ -3171,7 +3171,7 @@ namespace Js
 
         bool IsGeneratorAndJitIsDisabled()
         {
-            return (this->IsGenerator() || this->IsAsync()) && !(CONFIG_ISENABLED(Js::JitES6GeneratorsFlag) && !this->GetHasTry());
+            return this->IsCoroutine() && !(CONFIG_ISENABLED(Js::JitES6GeneratorsFlag) && !this->GetHasTry());
         }
 
         FunctionBodyFlags * GetAddressOfFlags() { return &this->flags; }
diff --git a/lib/Runtime/Base/FunctionInfo.h b/lib/Runtime/Base/FunctionInfo.h
@@ -58,6 +58,7 @@ namespace Js
         bool IsClassMethod() const { return ((this->attributes & ClassMethod) != 0); }
         bool IsModule() const { return ((this->attributes & Module) != 0); }
         bool HasSuperReference() const { return ((this->attributes & SuperReference) != 0); }
+        bool IsCoroutine() const { return ((this->attributes & (Async | Generator)) != 0); }
 
         BOOL HasBody() const { return functionBodyImpl != NULL; }
         BOOL HasParseableInfo() const { return this->HasBody() && !this->IsDeferredDeserializeFunction(); }
diff --git a/lib/Runtime/ByteCode/ByteCodeEmitter.cpp b/lib/Runtime/ByteCode/ByteCodeEmitter.cpp
@@ -1227,11 +1227,11 @@ Js::RegSlot ByteCodeGenerator::DefineOneFunction(ParseNode *pnodeFnc, FuncInfo *
     // If we are in a parameter scope and it is not merged with body scope then we have to create the child function as an inner function
     if (regEnv == funcInfoParent->frameDisplayRegister || regEnv == funcInfoParent->GetEnvRegister())
     {
-        m_writer.NewFunction(pnodeFnc->location, pnodeFnc->sxFnc.nestedIndex, pnodeFnc->sxFnc.IsGenerator() || pnodeFnc->sxFnc.IsAsync());
+        m_writer.NewFunction(pnodeFnc->location, pnodeFnc->sxFnc.nestedIndex, pnodeFnc->sxFnc.IsCoroutine());
     }
     else
     {
-        m_writer.NewInnerFunction(pnodeFnc->location, pnodeFnc->sxFnc.nestedIndex, regEnv, pnodeFnc->sxFnc.IsGenerator() || pnodeFnc->sxFnc.IsAsync());
+        m_writer.NewInnerFunction(pnodeFnc->location, pnodeFnc->sxFnc.nestedIndex, regEnv, pnodeFnc->sxFnc.IsCoroutine());
     }
 
     if (funcInfoParent->IsGlobalFunction() && (this->flags & fscrEval))
@@ -1717,7 +1717,7 @@ void ByteCodeGenerator::SetClosureRegisters(FuncInfo* funcInfo, Js::FunctionBody
 
 void ByteCodeGenerator::FinalizeRegisters(FuncInfo * funcInfo, Js::FunctionBody * byteCodeFunction)
 {
-    if (byteCodeFunction->IsGenerator() || byteCodeFunction->IsAsync())
+    if (byteCodeFunction->IsCoroutine())
     {
         // EmitYield uses 'false' to create the IteratorResult object
         funcInfo->AssignFalseConstRegister();
@@ -1751,7 +1751,7 @@ void ByteCodeGenerator::FinalizeRegisters(FuncInfo * funcInfo, Js::FunctionBody
     }
 
     // NOTE: The FB expects the yield reg to be the final non-temp.
-    if (byteCodeFunction->IsGenerator() || byteCodeFunction->IsAsync())
+    if (byteCodeFunction->IsCoroutine())
     {
         funcInfo->AssignYieldRegister();
     }
@@ -6717,9 +6717,9 @@ void EmitDestructuredArray(
 
     Js::RegSlot regException = Js::Constants::NoRegister;
     Js::RegSlot regOffset = Js::Constants::NoRegister;
-    bool isGenerator = funcInfo->byteCodeFunction->IsGenerator() || funcInfo->byteCodeFunction->IsAsync();
+    bool isCoroutine = funcInfo->byteCodeFunction->IsCoroutine();
 
-    if (isGenerator)
+    if (isCoroutine)
     {
         regException = funcInfo->AcquireTmpRegister();
         regOffset = funcInfo->AcquireTmpRegister();
@@ -6732,7 +6732,7 @@ void EmitDestructuredArray(
 
     ByteCodeGenerator::TryScopeRecord tryRecForTryFinally(Js::OpCode::TryFinallyWithYield, finallyLabel);
 
-    if (isGenerator)
+    if (isCoroutine)
     {
         byteCodeGenerator->Writer()->BrReg2(Js::OpCode::TryFinallyWithYield, finallyLabel, regException, regOffset);
         tryRecForTryFinally.reg1 = regException;
@@ -6747,7 +6747,7 @@ void EmitDestructuredArray(
     byteCodeGenerator->Writer()->Br(Js::OpCode::TryCatch, catchLabel);
 
     ByteCodeGenerator::TryScopeRecord tryRecForTry(Js::OpCode::TryCatch, catchLabel);
-    if (isGenerator)
+    if (isCoroutine)
     {
         byteCodeGenerator->tryScopeRecordsList.LinkToEnd(&tryRecForTry);
     }
diff --git a/lib/Runtime/ByteCode/ByteCodeGenerator.cpp b/lib/Runtime/ByteCode/ByteCodeGenerator.cpp
@@ -1698,7 +1698,7 @@ bool ByteCodeGenerator::CanStackNestedFunc(FuncInfo * funcInfo, bool trace)
 #endif
     Assert(!funcInfo->IsGlobalFunction());
     bool const doStackNestedFunc = !funcInfo->HasMaybeEscapedNestedFunc() && !IsInDebugMode()
-        && !funcInfo->byteCodeFunction->IsGenerator() && !funcInfo->byteCodeFunction->IsAsync()
+        && !funcInfo->byteCodeFunction->IsCoroutine()
         && !funcInfo->byteCodeFunction->IsModule();
     if (!doStackNestedFunc)
     {
@@ -2363,7 +2363,7 @@ FuncInfo* PreVisitFunction(ParseNode* pnode, ByteCodeGenerator* byteCodeGenerato
                     }
 #endif
                 }
-                funcInfo->SetHasHeapArguments(true, !pnode->sxFnc.IsGenerator() && !pnode->sxFnc.IsAsync() && doStackArgsOpt /*= Optimize arguments in backend*/);
+                funcInfo->SetHasHeapArguments(true, !pnode->sxFnc.IsCoroutine() && doStackArgsOpt /*= Optimize arguments in backend*/);
                 if (funcInfo->inArgsCount == 0)
                 {
                     // If no formals to function, no need to create the propertyid array
@@ -2430,8 +2430,7 @@ void AssignFuncSymRegister(ParseNode * pnode, ByteCodeGenerator * byteCodeGenera
                 byteCodeGenerator->AssignRegister(sym);
                 pnode->location = sym->GetLocation();
 
-                Assert(byteCodeGenerator->GetCurrentScope()->GetFunc() == sym->GetScope()->GetFunc() ||
-                    sym->GetScope()->GetFunc()->root->sxFnc.IsAsync());
+                Assert(byteCodeGenerator->GetCurrentScope()->GetFunc() == sym->GetScope()->GetFunc());
                 if (byteCodeGenerator->GetCurrentScope()->GetFunc() != sym->GetScope()->GetFunc())
                 {
                     Assert(GetParentFuncInfo(byteCodeGenerator->GetCurrentScope()->GetFunc()) == sym->GetScope()->GetFunc());
@@ -5030,18 +5029,6 @@ void AssignRegisters(ParseNode *pnode, ByteCodeGenerator *byteCodeGenerator)
             sym = pnode->sxVar.sym;
             Assert(sym != nullptr);
 
-            if (sym->GetScope()->GetEnclosingFunc() != byteCodeGenerator->TopFuncInfo())
-            {
-                FuncInfo* parentFunc = GetParentFuncInfo(byteCodeGenerator->TopFuncInfo());
-                Assert(parentFunc == sym->GetScope()->GetEnclosingFunc());
-                if (parentFunc->root->sxFnc.IsAsync())
-                {
-                    // async functions produce a situation where a var decl can have a symbol
-                    // declared from an enclosing function.  In this case just no-op the vardecl.
-                    return;
-                }
-            }
-
             Assert(sym->GetScope()->GetEnclosingFunc() == byteCodeGenerator->TopFuncInfo());
 
             if (pnode->sxVar.isBlockScopeFncDeclVar && sym->GetIsBlockVar())
diff --git a/lib/Runtime/ByteCode/Symbol.cpp b/lib/Runtime/ByteCode/Symbol.cpp
diff --git a/lib/Runtime/Language/InterpreterStackFrame.cpp b/lib/Runtime/Language/InterpreterStackFrame.cpp
diff --git a/lib/Runtime/Library/JavascriptFunction.cpp b/lib/Runtime/Library/JavascriptFunction.cpp
diff --git a/lib/Runtime/Library/JavascriptGeneratorFunction.cpp b/lib/Runtime/Library/JavascriptGeneratorFunction.cpp
diff --git a/lib/Runtime/Library/JavascriptGeneratorFunction.h b/lib/Runtime/Library/JavascriptGeneratorFunction.h
diff --git a/lib/Runtime/Library/JavascriptLibrary.cpp b/lib/Runtime/Library/JavascriptLibrary.cpp

Original file line number	Diff line number	Diff line change
`@@ -1437,7 +1437,7 @@ BailOutRecord::BailOutHelper(Js::JavascriptCallStackLayout * layout, Js::ScriptF`
`1437`	`1437`	`Js::InterpreterStackFrame* newInstance = nullptr;`
`1438`	`1438`	`Js::Var* allocation = nullptr;`
`1439`	`1439`
`1440`		`- if (executeFunction->IsGenerator() \|\| executeFunction->IsAsync())`
	`1440`	`+ if (executeFunction->IsCoroutine())`
`1441`	`1441`	`{`
`1442`	`1442`	`// If the FunctionBody is a generator then this call is being made by one of the three`
`1443`	`1443`	`// generator resuming methods: next(), throw(), or return(). They all pass the generator`
Original file line number	Diff line number	Diff line change
`@@ -1099,7 +1099,7 @@ FlowGraph::Destroy(void)`
`1099`	`1099`	`// Skipping Try blocks as we have dependency on blocks to get the last instr(see below in this function)`
`1100`	`1100`	`if (!fHasTry)`
`1101`	`1101`	`{`
`1102`		`- if (this->func->GetJnFunction()->IsGenerator() \|\| this->func->GetJnFunction()->IsAsync())`
	`1102`	`+ if (this->func->GetJnFunction()->IsCoroutine())`
`1103`	`1103`	`{`
`1104`	`1104`	`// the label could be a yield resume label, in which case we also need to remove it from the YieldOffsetResumeLabels list`
`1105`	`1105`	`this->func->MapUntilYieldOffsetResumeLabels([this, &labelInstr](int i, const YieldOffsetResumeLabel& yorl)`
Original file line number	Diff line number	Diff line change
`@@ -214,7 +214,7 @@ Func::Func(JitArenaAllocator alloc, CodeGenWorkItem workItem, const Js::Functi`
`214`	`214`	`m_nonTempLocalVars = Anew(this->m_alloc, BVSparse<JitArenaAllocator>, this->m_alloc);`
`215`	`215`	`}`
`216`	`216`
`217`		`- if (this->m_jnFunction->IsGenerator() \|\| this->m_jnFunction->IsAsync())`
	`217`	`+ if (this->m_jnFunction->IsCoroutine())`
`218`	`218`	`{`
`219`	`219`	`m_yieldOffsetResumeLabelList = YieldOffsetResumeLabelList::New(this->m_alloc);`
`220`	`220`	`}`
`@@ -846,8 +846,8 @@ Func::AjustLocalVarSlotOffset()`
`846`	`846`	`bool`
`847`	`847`	`Func::DoGlobOptsForGeneratorFunc()`
`848`	`848`	`{`
`849`		`- // Disable GlobOpt optimizations for generators and asyn functions initially. Will visit and enable each one by one.`
`850`		`- return !m_jnFunction->IsGenerator() && !m_jnFunction->IsAsync();`
	`849`	`+ // Disable GlobOpt optimizations for generators and async functions initially. Will visit and enable each one by one.`
	`850`	`+ return !m_jnFunction->IsCoroutine();`
`851`	`851`	`}`
`852`	`852`
`853`	`853`	`void`
Original file line number	Diff line number	Diff line change
`@@ -1365,7 +1365,7 @@ IRBuilder::BuildImplicitArgIns()`
`1365`	`1365`	`void`
`1366`	`1366`	`IRBuilder::BuildGeneratorPreamble()`
`1367`	`1367`	`{`
`1368`		`- if (!this->m_func->GetJnFunction()->IsGenerator() && !this->m_func->GetJnFunction()->IsAsync())`
	`1368`	`+ if (!this->m_func->GetJnFunction()->IsCoroutine())`
`1369`	`1369`	`{`
`1370`	`1370`	`return;`
`1371`	`1371`	`}`
Original file line number	Diff line number	Diff line change
`@@ -5084,7 +5084,7 @@ Lowerer::LowerNewScObjArrayNoArg(IR::Instr *newObjInstr)`
`5084`	`5084`	`void`
`5085`	`5085`	`Lowerer::LowerPrologEpilog()`
`5086`	`5086`	`{`
`5087`		`- if (m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync())`
	`5087`	`+ if (m_func->GetJnFunction()->IsCoroutine())`
`5088`	`5088`	`{`
`5089`	`5089`	`LowerGeneratorResumeJumpTable();`
`5090`	`5090`	`}`
`@@ -5121,7 +5121,7 @@ Lowerer::LowerPrologEpilogAsmJs()`
`5121`	`5121`	`void`
`5122`	`5122`	`Lowerer::LowerGeneratorResumeJumpTable()`
`5123`	`5123`	`{`
`5124`		`- Assert(m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync());`
	`5124`	`+ Assert(m_func->GetJnFunction()->IsCoroutine());`
`5125`	`5125`
`5126`	`5126`	`IR::Instr * jumpTableInstr = m_func->m_headInstr;`
`5127`	`5127`	`AssertMsg(jumpTableInstr->IsEntryInstr(), "First instr isn't an EntryInstr...");`
`@@ -7568,7 +7568,7 @@ Lowerer::LoadArgumentCount(IR::Instr *const instr)`
`7568`	`7568`	`instr->SetSrc1(IR::IntConstOpnd::New(instr->m_func->actualCount, TyUint32, instr->m_func, true));`
`7569`	`7569`	`LowererMD::ChangeToAssign(instr);`
`7570`	`7570`	`}`
`7571`		`- else if (instr->m_func->GetJnFunction()->IsGenerator() \|\| instr->m_func->GetJnFunction()->IsAsync())`
	`7571`	`+ else if (instr->m_func->GetJnFunction()->IsCoroutine())`
`7572`	`7572`	`{`
`7573`	`7573`	`IR::SymOpnd* symOpnd = LoadCallInfo(instr);`
`7574`	`7574`	`instr->SetSrc1(symOpnd);`
`@@ -9607,7 +9607,7 @@ IR::Instr Lowerer::LowerRestParameter(IR::Opnd formalsOpnd, IR::Opnd *dstOpnd,`
`9607`	`9607`
`9608`	`9608`	`LoadScriptContext(helperCallInstr);`
`9609`	`9609`
`9610`		`- BOOL isGenerator = this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync();`
	`9610`	`+ BOOL isGenerator = this->m_func->GetJnFunction()->IsCoroutine();`
`9611`	`9611`
`9612`	`9612`	`// Elements pointer = ebp + (formals count + formals offset + 1)*sizeof(Var)`
`9613`	`9613`	`IR::RegOpnd *srcOpnd = isGenerator ? generatorArgsPtrOpnd : IR::Opnd::CreateFramePointerOpnd(this->m_func);`
`@@ -9715,7 +9715,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)`
`9715`	`9715`	`// $createRestArray`
`9716`	`9716`	`instrArgIn->InsertBefore(createRestArrayLabel);`
`9717`	`9717`
`9718`		`- if (m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync())`
	`9718`	`+ if (m_func->GetJnFunction()->IsCoroutine())`
`9719`	`9719`	`{`
`9720`	`9720`	`generatorArgsPtrOpnd = LoadGeneratorArgsPtr(instrArgIn);`
`9721`	`9721`	`}`
`@@ -9734,7 +9734,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)`
`9734`	`9734`	`if (argIndex == 1)`
`9735`	`9735`	`{`
`9736`	`9736`	`// The "this" argument is not source-dependent and doesn't need to be checked.`
`9737`		`- if (m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync())`
	`9737`	`+ if (m_func->GetJnFunction()->IsCoroutine())`
`9738`	`9738`	`{`
`9739`	`9739`	`generatorArgsPtrOpnd = LoadGeneratorArgsPtr(instrArgIn);`
`9740`	`9740`	`ConvertArgOpndIfGeneratorFunction(instrArgIn, generatorArgsPtrOpnd);`
`@@ -9788,7 +9788,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)`
`9788`	`9788`
`9789`	`9789`	`// Now insert all the checks and undef-assigns.`
`9790`	`9790`
`9791`		`- if (m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync())`
	`9791`	`+ if (m_func->GetJnFunction()->IsCoroutine())`
`9792`	`9792`	`{`
`9793`	`9793`	`generatorArgsPtrOpnd = LoadGeneratorArgsPtr(instrInsert);`
`9794`	`9794`	`}`
`@@ -9958,7 +9958,7 @@ Lowerer::LowerArgIn(IR::Instr *instrArgIn)`
`9958`	`9958`	`void`
`9959`	`9959`	`Lowerer::ConvertArgOpndIfGeneratorFunction(IR::Instr instrArgIn, IR::RegOpnd generatorArgsPtrOpnd)`
`9960`	`9960`	`{`
`9961`		`- if (this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync())`
	`9961`	`+ if (this->m_func->GetJnFunction()->IsCoroutine())`
`9962`	`9962`	`{`
`9963`	`9963`	`// Replace stack param operand with offset into arguments array held by`
`9964`	`9964`	`// the generator object.`
`@@ -10664,7 +10664,7 @@ Lowerer::LoadCallInfo(IR::Instr * instrInsert)`
`10664`	`10664`	`IR::SymOpnd * srcOpnd;`
`10665`	`10665`	`Func * func = instrInsert->m_func;`
`10666`	`10666`
`10667`		`- if (func->GetJnFunction()->IsGenerator() \|\| func->GetJnFunction()->IsAsync())`
	`10667`	`+ if (func->GetJnFunction()->IsCoroutine())`
`10668`	`10668`	`{`
`10669`	`10669`	`// Generator function arguments and ArgumentsInfo are not on the stack. Instead they`
`10670`	`10670`	`// are accessed off the generator object (which is prm1).`
`@@ -18111,7 +18111,7 @@ IR::IndirOpnd*`
`18111`	`18111`	`Lowerer::GetArgsIndirOpndForTopFunction(IR::Instr* ldElem, IR::Opnd* valueOpnd)`
`18112`	`18112`	`{`
`18113`	`18113`	`// Load argument set dst = [ebp + index] (or grab from the generator object if m_func is a generator function).`
`18114`		`- IR::RegOpnd *baseOpnd = (m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync()) ? LoadGeneratorArgsPtr(ldElem) : IR::Opnd::CreateFramePointerOpnd(m_func);`
	`18114`	`+ IR::RegOpnd *baseOpnd = m_func->GetJnFunction()->IsCoroutine() ? LoadGeneratorArgsPtr(ldElem) : IR::Opnd::CreateFramePointerOpnd(m_func);`
`18115`	`18115`	`IR::IndirOpnd* argIndirOpnd = nullptr;`
`18116`	`18116`	`// The stack looks like this:`
`18117`	`18117`	`// ...`
`@@ -18125,7 +18125,7 @@ Lowerer::GetArgsIndirOpndForTopFunction(IR::Instr* ldElem, IR::Opnd* valueOpnd)`
`18125`	`18125`
`18126`	`18126`	`//actual arguments offset is LowererMD::GetFormalParamOffset() + 1 (this)`
`18127`	`18127`
`18128`		`- uint16 actualOffset = (m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync()) ? 1 : GetFormalParamOffset() + 1; //5`
	`18128`	`+ uint16 actualOffset = m_func->GetJnFunction()->IsCoroutine() ? 1 : GetFormalParamOffset() + 1; //5`
`18129`	`18129`	`Assert(actualOffset == 5 \|\| m_func->GetJnFunction()->IsGenerator());`
`18130`	`18130`	`if (valueOpnd->IsIntConstOpnd())`
`18131`	`18131`	`{`
`@@ -20366,7 +20366,7 @@ Lowerer::GenerateLoadNewTarget(IR::Instr* instrInsert)`
`20366`	`20366`
`20367`	`20367`	`Assert(!func->IsInlinee());`
`20368`	`20368`
`20369`		`- if (func->GetJnFunction()->IsGenerator() \|\| func->GetJnFunction()->IsAsync())`
	`20369`	`+ if (func->GetJnFunction()->IsCoroutine())`
`20370`	`20370`	`{`
`20371`	`20371`	`instrInsert->SetSrc1(opndUndefAddress);`
`20372`	`20372`	`LowererMD::ChangeToAssign(instrInsert);`
`@@ -21101,7 +21101,7 @@ void Lowerer::GenerateNullOutGeneratorFrame(IR::Instr* insertInstr)`
`21101`	`21101`
`21102`	`21102`	`void Lowerer::LowerFunctionExit(IR::Instr* funcExit)`
`21103`	`21103`	`{`
`21104`		`- if (m_func->GetJnFunction()->IsGenerator() \|\| m_func->GetJnFunction()->IsAsync())`
	`21104`	`+ if (m_func->GetJnFunction()->IsCoroutine())`
`21105`	`21105`	`{`
`21106`	`21106`	`GenerateNullOutGeneratorFrame(funcExit->m_prev);`
`21107`	`21107`	`}`
Original file line number	Diff line number	Diff line change
`@@ -140,7 +140,7 @@ LowererMDArch::Init(LowererMD *lowererMD)`
`140`	`140`	`IR::Instr *`
`141`	`141`	`LowererMDArch::LoadInputParamPtr(IR::Instr instrInsert, IR::RegOpnd optionalDstOpnd /* = nullptr */)`
`142`	`142`	`{`
`143`		`- if (this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync())`
	`143`	`+ if (this->m_func->GetJnFunction()->IsCoroutine())`
`144`	`144`	`{`
`145`	`145`	`IR::RegOpnd * argPtrRegOpnd = Lowerer::LoadGeneratorArgsPtr(instrInsert);`
`146`	`146`	`IR::IndirOpnd * indirOpnd = IR::IndirOpnd::New(argPtrRegOpnd, 1 * MachPtr, TyMachPtr, this->m_func);`
`@@ -380,7 +380,7 @@ LowererMDArch::LoadHeapArguments(IR::Instr instrArgs, bool force / = false */,`
`380`	`380`	`this->m_func->SetArgOffset(paramSym, 2 * MachPtr);`
`381`	`381`	`IR::Opnd * srcOpnd = IR::SymOpnd::New(paramSym, TyMachReg, func);`
`382`	`382`
`383`		`- if (this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync())`
	`383`	`+ if (this->m_func->GetJnFunction()->IsCoroutine())`
`384`	`384`	`{`
`385`	`385`	`// the function object for generator calls is a GeneratorVirtualScriptFunction object`
`386`	`386`	`// and we need to pass the real JavascriptGeneratorFunction object so grab it instead`
`@@ -430,7 +430,7 @@ LowererMDArch::LoadFuncExpression(IR::Instr *instrFuncExpr)`
`430`	`430`	`paramOpnd = IR::SymOpnd::New(paramSym, TyMachReg, this->m_func);`
`431`	`431`	`}`
`432`	`432`
`433`		`- if (instrFuncExpr->m_func->GetJnFunction()->IsGenerator() \|\| instrFuncExpr->m_func->GetJnFunction()->IsAsync())`
	`433`	`+ if (instrFuncExpr->m_func->GetJnFunction()->IsCoroutine())`
`434`	`434`	`{`
`435`	`435`	`// the function object for generator calls is a GeneratorVirtualScriptFunction object`
`436`	`436`	`// and we need to return the real JavascriptGeneratorFunction object so grab it before`
Original file line number	Diff line number	Diff line change
`@@ -1993,7 +1993,7 @@ LowererMD::Init(Lowerer *lowerer)`
`1993`	`1993`	`IR::Instr *`
`1994`	`1994`	`LowererMD::LoadInputParamPtr(IR::Instr * instrInsert, IR::RegOpnd * optionalDstOpnd /* = nullptr */)`
`1995`	`1995`	`{`
`1996`		`- if (this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync())`
	`1996`	`+ if (this->m_func->GetJnFunction()->IsCoroutine())`
`1997`	`1997`	`{`
`1998`	`1998`	`IR::RegOpnd * argPtrRegOpnd = Lowerer::LoadGeneratorArgsPtr(instrInsert);`
`1999`	`1999`	`IR::IndirOpnd * indirOpnd = IR::IndirOpnd::New(argPtrRegOpnd, 1 * MachPtr, TyMachPtr, this->m_func);`
`@@ -2087,7 +2087,7 @@ LowererMD::LoadStackArgPtr(IR::Instr * instr)`
`2087`	`2087`	`instr->SetSrc1(tmpOpnd);`
`2088`	`2088`	`instr->SetSrc2(IR::IntConstOpnd::New(sizeof(Js::Var), TyMachReg, this->m_func));`
`2089`	`2089`	`}`
`2090`		`- else if (this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync())`
	`2090`	`+ else if (this->m_func->GetJnFunction()->IsCoroutine())`
`2091`	`2091`	`{`
`2092`	`2092`	`IR::Instr *instr2 = LoadInputParamPtr(instr, instr->UnlinkDst()->AsRegOpnd());`
`2093`	`2093`	`instr->Remove();`
Original file line number	Diff line number	Diff line change
`@@ -137,7 +137,7 @@ LowererMDArch::Init(LowererMD *lowererMD)`
`137`	`137`	`IR::Instr *`
`138`	`138`	`LowererMDArch::LoadInputParamPtr(IR::Instr instrInsert, IR::RegOpnd optionalDstOpnd /* = nullptr */)`
`139`	`139`	`{`
`140`		`- if (this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync())`
	`140`	`+ if (this->m_func->GetJnFunction()->IsCoroutine())`
`141`	`141`	`{`
`142`	`142`	`IR::RegOpnd * argPtrRegOpnd = Lowerer::LoadGeneratorArgsPtr(instrInsert);`
`143`	`143`	`IR::IndirOpnd * indirOpnd = IR::IndirOpnd::New(argPtrRegOpnd, 1 * MachPtr, TyMachPtr, this->m_func);`
`@@ -334,7 +334,7 @@ LowererMDArch::LoadHeapArguments(IR::Instr instrArgs, bool force, IR::Opnd opn`
`334`	`334`	`this->m_func->SetArgOffset(paramSym, 2 * MachPtr);`
`335`	`335`	`IR::Opnd *srcOpnd = IR::SymOpnd::New(paramSym, TyMachReg, func);`
`336`	`336`
`337`		`- if (this->m_func->GetJnFunction()->IsGenerator() \|\| this->m_func->GetJnFunction()->IsAsync())`
	`337`	`+ if (this->m_func->GetJnFunction()->IsCoroutine())`
`338`	`338`	`{`
`339`	`339`	`// the function object for generator calls is a GeneratorVirtualScriptFunction object`
`340`	`340`	`// and we need to pass the real JavascriptGeneratorFunction object so grab it instead`
`@@ -501,7 +501,7 @@ LowererMDArch::LoadFuncExpression(IR::Instr *instrFuncExpr)`
`501`	`501`	`paramOpnd = IR::SymOpnd::New(paramSym, TyMachReg, func);`
`502`	`502`	`}`
`503`	`503`
`504`		`- if (instrFuncExpr->m_func->GetJnFunction()->IsGenerator() \|\| instrFuncExpr->m_func->GetJnFunction()->IsAsync())`
	`504`	`+ if (instrFuncExpr->m_func->GetJnFunction()->IsCoroutine())`
`505`	`505`	`{`
`506`	`506`	`// the function object for generator calls is a GeneratorVirtualScriptFunction object`
`507`	`507`	`// and we need to return the real JavascriptGeneratorFunction object so grab it before`
Original file line number	Diff line number	Diff line change
`@@ -3171,7 +3171,7 @@ namespace Js`
`3171`	`3171`
`3172`	`3172`	`bool IsGeneratorAndJitIsDisabled()`
`3173`	`3173`	`{`
`3174`		`- return (this->IsGenerator() \|\| this->IsAsync()) && !(CONFIG_ISENABLED(Js::JitES6GeneratorsFlag) && !this->GetHasTry());`
	`3174`	`+ return this->IsCoroutine() && !(CONFIG_ISENABLED(Js::JitES6GeneratorsFlag) && !this->GetHasTry());`
`3175`	`3175`	`}`
`3176`	`3176`
`3177`	`3177`	`FunctionBodyFlags * GetAddressOfFlags() { return &this->flags; }`