[6.0 cherry-pick][embedded] Avoid a crash on location-less SIL functions in PerformanceDiagnostics

lib/SILOptimizer/Mandatory/PerformanceDiagnostics.cpp

@@ -810,15 +810,22 @@ class PerformanceDiagnosticsPass : public SILModuleTransform {
       SmallVector<SILFunction *, 8> constructorsAndDestructors;
 
       for (SILFunction &function : *module) {
-        auto func = function.getLocation().getAsASTNode<AbstractFunctionDecl>();
-        if (func) {
-          if (isa<DestructorDecl>(func) || isa<ConstructorDecl>(func)) {
-            constructorsAndDestructors.push_back(&function);
-            continue;
-          }
-          if (getMethodDispatch(func) == MethodDispatch::Class) {
-            vtableMembers.push_back(&function);
-            continue;
+        // There might be SILFunctions without a location, e.g.
+        // swift_readAtKeyPath generated by SILGen for keypaths. It's okay to
+        // skip the ctor/dtor/method detection logic for those, such functions
+        // still end up in the "others" list and are still visited.
+        if (function.hasLocation()) {
+          auto func =
+              function.getLocation().getAsASTNode<AbstractFunctionDecl>();
+          if (func) {
+            if (isa<DestructorDecl>(func) || isa<ConstructorDecl>(func)) {
+              constructorsAndDestructors.push_back(&function);
+              continue;
+            }
+            if (getMethodDispatch(func) == MethodDispatch::Class) {
+              vtableMembers.push_back(&function);
+              continue;
+            }
           }
         }
 

test/embedded/keypath-crash.swift

@@ -0,0 +1,44 @@
+// RUN: %target-swift-emit-ir %s -module-name=main -enable-experimental-feature Embedded | %FileCheck %s
+
+// REQUIRES: swift_in_compiler
+// REQUIRES: OS=macosx || OS=linux-gnu
+
+@propertyWrapper
+@dynamicMemberLookup
+public struct Binding<Value> {
+  public var wrappedValue: Value
+
+  init(get: @escaping () -> Value, set: @escaping (Value) -> Void) {
+    self.wrappedValue = get()
+  }
+
+  subscript<Subject>(dynamicMember keyPath: WritableKeyPath<Value, Subject>) -> Binding<Subject> {
+    get { fatalError() }
+  }
+}
+
+
+public struct State<Wrapped> {
+  public var wrappedValue: Wrapped
+
+  public init(wrappedValue: Wrapped) {
+    self.wrappedValue = wrappedValue
+  }
+  public var projectedValue: Projection {
+    Projection(wrappedValue: wrappedValue)
+  }
+
+  @dynamicMemberLookup
+  public struct Projection {
+    var wrappedValue: Wrapped
+    public subscript<Member>(dynamicMember keyPath: ReferenceWritableKeyPath<Wrapped, Member>) -> Binding<Member> where Wrapped: AnyObject {
+      Binding(get: {
+        wrappedValue[keyPath: keyPath]
+      }, set: { newValue in
+        wrappedValue[keyPath: keyPath] = newValue
+      })
+    }
+  }
+}
+
+// CHECK: define {{.*}}@main(