[1.8>master] [MERGE #4388 @MikeHolman] Stop trying to JIT if OOP JIT disconnected

Merge pull request #4388 from MikeHolman:nojitondc

Continuing to attempt to JIT makes the interpreter much slower than it would otherwise be, because you end up creating a work item every call/every loop top

Author: MikeHolman

lib/Backend/NativeCodeGenerator.cpp

@@ -1870,9 +1870,19 @@ NativeCodeGenerator::Prioritize(JsUtil::Job *const job, const bool forceAddJobTo
     }
     else
     {
-        if(!forceAddJobToProcessor && !functionBody->TryTransitionToJitExecutionMode())
+        if (!forceAddJobToProcessor)
         {
-            return;
+            if (!functionBody->TryTransitionToJitExecutionMode())
+            {
+                return;
+            }
+#if ENABLE_OOP_NATIVE_CODEGEN
+            // If for some reason OOP JIT isn't connected (e.g. it crashed), don't attempt to JIT
+            if (JITManager::GetJITManager()->IsOOPJITEnabled() && !JITManager::GetJITManager()->IsConnected())
+            {
+                return;
+            }
+#endif
         }
 
         jitMode = functionBody->GetExecutionMode();

lib/Runtime/Language/InterpreterStackFrame.cpp

@@ -6084,6 +6084,13 @@ const byte * InterpreterStackFrame::OP_ProfiledLoopBodyStart(uint loopId)
             }
 
 #if ENABLE_NATIVE_CODEGEN
+#if ENABLE_OOP_NATIVE_CODEGEN
+            // If for some reason OOP JIT isn't connected (e.g. it crashed), don't attempt to JIT a loop body
+            if (JITManager::GetJITManager()->IsOOPJITEnabled() && !JITManager::GetJITManager()->IsConnected())
+            {
+                return nullptr;
+            }
+#endif
             // If the job is not scheduled then we need to schedule it now.
             // It is possible a job was scheduled earlier and we find ourselves looking at the same entry point
             // again. For example, if the function with the loop was JITed and bailed out then as we finish

lib/Runtime/Language/WAsmjsUtils.cpp

@@ -96,14 +96,23 @@ template<> Types RegisterSpace::GetRegisterSpaceType<AsmJsSIMDValue>(){return WA
     bool ShouldJitFunction(Js::FunctionBody* body, uint interpretedCount)
     {
 #if ENABLE_NATIVE_CODEGEN
-        const bool noJit = PHASE_OFF(Js::BackEndPhase, body) ||
+        if (PHASE_OFF(Js::BackEndPhase, body) ||
             PHASE_OFF(Js::FullJitPhase, body) ||
             body->GetScriptContext()->GetConfig()->IsNoNative() ||
-            body->GetIsAsmJsFullJitScheduled();
+            body->GetIsAsmJsFullJitScheduled())
+        {
+            return false;
+        }
+#if ENABLE_OOP_NATIVE_CODEGEN
+        if (JITManager::GetJITManager()->IsOOPJITEnabled() && !JITManager::GetJITManager()->IsConnected())
+        {
+            return false;
+        }
+#endif
         const bool forceNative = CONFIG_ISENABLED(Js::ForceNativeFlag);
         const uint minAsmJsInterpretRunCount = (uint)CONFIG_FLAG(MinAsmJsInterpreterRunCount);
         const uint maxAsmJsInterpretRunCount = (uint)CONFIG_FLAG(MaxAsmJsInterpreterRunCount);
-        return !noJit && (forceNative || interpretedCount >= minAsmJsInterpretRunCount || interpretedCount >= maxAsmJsInterpretRunCount);
+        return forceNative || interpretedCount >= minAsmJsInterpretRunCount || interpretedCount >= maxAsmJsInterpretRunCount;
 #else
         return false;
 #endif