SwiftCompilerSources: add Context.notifyDependency(onBodyOf:)

It notifies the pass manager that the optimization result of the current pass depends on the body (i.e. SIL instructions) of another function than the currently optimized one.

Author: eeckstein

SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/SimplifyBuiltin.swift

@@ -101,6 +101,8 @@ private extension BuiltinInst {
     guard let callee = calleeOfOnce, callee.isDefinition else {
       return
     }
+    context.notifyDependency(onBodyOf: callee)
+
     // If the callee is side effect-free we can remove the whole builtin "once".
     // We don't use the callee's memory effects but instead look at all callee instructions
     // because memory effects are not computed in the Onone pipeline, yet.

SwiftCompilerSources/Sources/Optimizer/PassManager/Context.swift

@@ -210,6 +210,12 @@ extension MutatingContext {
   func notifyBranchesChanged() {
     _bridged.asNotificationHandler().notifyChanges(.branchesChanged)
   }
+
+  /// Notifies the pass manager that the optimization result of the current pass depends
+  /// on the body (i.e. SIL instructions) of another function than the currently optimized one.
+  func notifyDependency(onBodyOf otherFunction: Function) {
+    _bridged.notifyDependencyOnBodyOf(otherFunction.bridged)
+  }
 }
 
 /// The context which is passed to the run-function of a FunctionPass.

include/swift/SILOptimizer/OptimizerBridging.h

@@ -171,6 +171,7 @@ struct BridgedPassContext {
 
   SWIFT_IMPORT_UNSAFE BridgedOwnedString getModuleDescription() const;
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedChangeNotificationHandler asNotificationHandler() const;
+  BRIDGED_INLINE void notifyDependencyOnBodyOf(BridgedFunction otherFunction) const;
   BRIDGED_INLINE SILStage getSILStage() const;
   BRIDGED_INLINE bool hadError() const;
   BRIDGED_INLINE bool moduleIsSerialized() const;

include/swift/SILOptimizer/OptimizerBridgingImpl.h

@@ -137,6 +137,12 @@ BridgedChangeNotificationHandler BridgedPassContext::asNotificationHandler() con
   return {invocation};
 }
 
+void BridgedPassContext::notifyDependencyOnBodyOf(BridgedFunction otherFunction) const {
+  // Currently `otherFunction` is ignored. We could design a more accurate dependency system
+  // in the pass manager, which considers the actual function. But it's probaboly not worth the effort.
+  invocation->getPassManager()->setDependingOnCalleeBodies();
+}
+
 BridgedPassContext::SILStage BridgedPassContext::getSILStage() const {
   return (SILStage)invocation->getPassManager()->getModule()->getStage();
 }