[ORC] Make the VModuleKey optional, propagate it via MaterializationUnit and

MaterializationResponsibility.

VModuleKeys are intended to enable selective removal of modules from a JIT
session, however for a wide variety of use cases selective removal is not
needed and introduces unnecessary overhead. As of this commit, the default
constructed VModuleKey value is reserved as a "do not track" value, and
becomes the default when adding a new module to the JIT.

This commit also changes the propagation of VModuleKeys. They were passed
alongside the MaterializationResponsibity instance in XXLayer::emit methods,
but are now propagated as part of the MaterializationResponsibility instance
itself (and as part of MaterializationUnit when stored in a JITDylib).
Associating VModuleKeys with MaterializationUnits in this way should allow
for a thread-safe module removal mechanism in the future, even when a module
is in the process of being compiled, by having the
MaterializationResponsibility object check in on its VModuleKey's state
before commiting its results to the JITDylib.

llvm-svn: 344643

1 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/ExecutionEngine/Orc/IRCompileLayer.cpp b/llvm/lib/ExecutionEngine/Orc/IRCompileLayer.cpp
index 6d029e16ba9..d952d1be70d 100644
--- a/llvm/lib/ExecutionEngine/Orc/IRCompileLayer.cpp
+++ b/llvm/lib/ExecutionEngine/Orc/IRCompileLayer.cpp
@@ -21,19 +21,19 @@ void IRCompileLayer::setNotifyCompiled(NotifyCompiledFunction NotifyCompiled) {
   this->NotifyCompiled = std::move(NotifyCompiled);
 }
 
-void IRCompileLayer::emit(MaterializationResponsibility R, VModuleKey K,
-                           ThreadSafeModule TSM) {
+void IRCompileLayer::emit(MaterializationResponsibility R,
+                          ThreadSafeModule TSM) {
   assert(TSM.getModule() && "Module must not be null");
 
   if (auto Obj = Compile(*TSM.getModule())) {
     {
       std::lock_guard<std::mutex> Lock(IRLayerMutex);
       if (NotifyCompiled)
-        NotifyCompiled(K, std::move(TSM));
+        NotifyCompiled(R.getVModuleKey(), std::move(TSM));
       else
         TSM = ThreadSafeModule();
     }
-    BaseLayer.emit(std::move(R), std::move(K), std::move(*Obj));
+    BaseLayer.emit(std::move(R), std::move(*Obj));
   } else {
     R.failMaterialization();
     getExecutionSession().reportError(Obj.takeError());