Merge pull request #70317 from tshortli/silgen-dont-skip-func-nested-in-closure-in-inlinable-func

SILGen: Don't skip functions nested in closures in inlinable functions

Author: tshortli

lib/SILGen/SILGen.cpp

@@ -804,24 +804,23 @@ bool SILGenModule::shouldSkipDecl(Decl *D) {
   if (!getASTContext().SILOpts.SkipNonExportableDecls)
     return false;
 
-  if (auto *afd = dyn_cast<AbstractFunctionDecl>(D)) {
-    do {
-      if (afd->isExposedToClients())
-        return false;
+  if (D->isExposedToClients())
+    return false;
 
-      // If this function is nested within another function that is exposed to
-      // clients then it should be emitted.
-      auto dc = afd->getDeclContext()->getAsDecl();
-      afd = dc ? dyn_cast<AbstractFunctionDecl>(dc) : nullptr;
-    } while (afd);
+  if (isa<AbstractFunctionDecl>(D)) {
+    // If this function is nested within another function that is exposed to
+    // clients then it should be emitted.
+    auto dc = D->getDeclContext();
+    do {
+      if (auto afd = dyn_cast<AbstractFunctionDecl>(dc))
+        if (afd->isExposedToClients())
+          return false;
+    } while ((dc = dc->getParent()));
 
     // We didn't find a parent function that is exposed.
     return true;
   }
 
-  if (D->isExposedToClients())
-    return false;
-
   return true;
 }
 

test/SILGen/skip_non_exportable_decls.swift

@@ -26,12 +26,26 @@ internal func internalFunc() {}
 // CHECK-NO-SKIP: sil hidden{{.*}} @$s4Test022internalFuncWithNestedC0yyF : $@convention(thin) () -> () {
 // CHECK-SKIP-NOT: s4Test022internalFuncWithNestedC0yyF
 internal func internalFuncWithNestedFunc() {
+  defer { internalFunc() }
   func nested() {}
   nested()
+  let _: () -> () = {
+    defer { internalFunc() }
+    internalFunc()
+  }()
 }
+// CHECK-NO-SKIP: sil private{{.*}} @$s4Test022internalFuncWithNestedC0yyF6$deferL_yyF : $@convention(thin) () -> () {
+// CHECK-SKIP-NOT: s4Test022internalFuncWithNestedC0yyF6$deferL_yyF
+
 // CHECK-NO-SKIP: sil private{{.*}} @$s4Test022internalFuncWithNestedC0yyF6nestedL_yyF : $@convention(thin) () -> () {
 // CHECK-SKIP-NOT: s4Test022internalFuncWithNestedC0yyF6nestedL_yyF
 
+// CHECK-NO-SKIP: sil private{{.*}} @$s4Test022internalFuncWithNestedC0yyFyycyXEfU_ : $@convention(thin) () -> @owned @callee_guaranteed () -> () {
+// CHECK-SKIP-NOT: s4Test022internalFuncWithNestedC0yyFyycyXEfU_
+
+// CHECK-NO-SKIP: sil private{{.*}} @$s4Test022internalFuncWithNestedC0yyFyycyXEfU_6$deferL_yyF : $@convention(thin) () -> () {
+// CHECK-SKIP-NOT: @$s4Test022internalFuncWithNestedC0yyFyycyXEfU_6$deferL_yyF
+
 // CHECK: sil{{.*}} @$s4Test10publicFuncyyF : $@convention(thin) () -> () {
 public func publicFunc() {}
 
@@ -66,9 +80,15 @@ public var publicGlobalVar = 1
   defer { publicFunc() }
   func nested() {}
   nested()
+  let _: () -> () = {
+    defer { publicFunc() }
+    publicFunc()
+  }()
 }
 // CHECK: sil shared [serialized]{{.*}} @$s4Test023inlinableFuncWithNestedC0yyF6$deferL_yyF : $@convention(thin) () -> () {
 // CHECK: sil shared [serialized]{{.*}} @$s4Test023inlinableFuncWithNestedC0yyF6nestedL_yyF : $@convention(thin) () -> () {
+// CHECK: sil shared [serialized]{{.*}} @$s4Test023inlinableFuncWithNestedC0yyFyycyXEfU_ : $@convention(thin) () -> @owned @callee_guaranteed () -> () {
+// CHECK: sil shared [serialized]{{.*}} @$s4Test023inlinableFuncWithNestedC0yyFyycyXEfU_6$deferL_yyF : $@convention(thin) () -> () {
 
 private class PrivateClass {
   // CHECK-NO-SKIP: sil private{{.*}} @$s4Test12PrivateClass33_CFB3F9DC47F5EF9E1D08B58758351A08LLCfd : $@convention(method) (@guaranteed PrivateClass) -> @owned Builtin.NativeObject {