Run ObjCARCContract when optimizing no matter the IRGenOutputKind.

lib/IRGen/IRGen.cpp

@@ -15,11 +15,10 @@
 //===----------------------------------------------------------------------===//
 
 #define DEBUG_TYPE "irgen"
-#include "swift/Subsystems.h"
+#include "IRGenModule.h"
 #include "swift/AST/DiagnosticsIRGen.h"
 #include "swift/AST/IRGenOptions.h"
 #include "swift/AST/LinkLibrary.h"
-#include "swift/SIL/SILModule.h"
 #include "swift/Basic/Defer.h"
 #include "swift/Basic/Dwarf.h"
 #include "swift/Basic/Platform.h"
@@ -29,51 +28,57 @@
 #include "swift/ClangImporter/ClangImporter.h"
 #include "swift/IRGen/IRGenPublic.h"
 #include "swift/IRGen/IRGenSILPasses.h"
-#include "swift/LLVMPasses/PassesFwd.h"
 #include "swift/LLVMPasses/Passes.h"
-#include "swift/SILOptimizer/PassManager/Passes.h"
+#include "swift/LLVMPasses/PassesFwd.h"
+#include "swift/SIL/SILModule.h"
 #include "swift/SILOptimizer/PassManager/PassManager.h"
 #include "swift/SILOptimizer/PassManager/PassPipeline.h"
+#include "swift/SILOptimizer/PassManager/Passes.h"
+#include "swift/Subsystems.h"
 #include "clang/Basic/TargetInfo.h"
-#include "llvm/Bitcode/BitcodeWriterPass.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Bitcode/BitcodeWriter.h"
+#include "llvm/Bitcode/BitcodeWriterPass.h"
 #include "llvm/CodeGen/BasicTTIImpl.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/IRPrintingPasses.h"
-#include "llvm/IR/LegacyPassManager.h"
 #include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/LegacyPassManager.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/ValueSymbolTable.h"
 #include "llvm/IR/Verifier.h"
 #include "llvm/Linker/Linker.h"
 #include "llvm/MC/SubtargetFeature.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/FormattedStream.h"
-#include "llvm/Support/TargetRegistry.h"
-#include "llvm/Support/Path.h"
-#include "llvm/Support/Mutex.h"
 #include "llvm/Support/MD5.h"
-#include "llvm/ADT/StringSet.h"
-#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Support/Mutex.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/TargetRegistry.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetSubtargetInfo.h"
-#include "llvm/Transforms/Instrumentation.h"
 #include "llvm/Transforms/IPO.h"
 #include "llvm/Transforms/IPO/AlwaysInliner.h"
 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
+#include "llvm/Transforms/Instrumentation.h"
 #include "llvm/Transforms/ObjCARC.h"
-#include "llvm/Object/ObjectFile.h"
-#include "IRGenModule.h"
 
 #include <thread>
 
 using namespace swift;
 using namespace irgen;
 using namespace llvm;
 
+static cl::opt<bool> DisableObjCARCContract(
+    "disable-objc-arc-contract", cl::Hidden,
+    cl::desc("Disable running objc arc contract for testing purposes"));
+
 namespace {
 // We need this to access IRGenOptions from extension functions
 class PassManagerBuilderWrapper : public PassManagerBuilder {
@@ -446,6 +451,13 @@ bool swift::performLLVM(IRGenOptions &Opts, DiagnosticEngine *Diags,
 
   legacy::PassManager EmitPasses;
 
+  // Make sure we do ARC contraction under optimization.  We don't
+  // rely on any other LLVM ARC transformations, but we do need ARC
+  // contraction to add the objc_retainAutoreleasedReturnValue
+  // assembly markers and remove clang.arc.used.
+  if (Opts.Optimize && !DisableObjCARCContract)
+    EmitPasses.add(createObjCARCContractPass());
+
   // Set up the final emission passes.
   switch (Opts.OutputKind) {
   case IRGenOutputKind::Module:
@@ -466,13 +478,6 @@ bool swift::performLLVM(IRGenOptions &Opts, DiagnosticEngine *Diags,
     EmitPasses.add(createTargetTransformInfoWrapperPass(
         TargetMachine->getTargetIRAnalysis()));
 
-    // Make sure we do ARC contraction under optimization.  We don't
-    // rely on any other LLVM ARC transformations, but we do need ARC
-    // contraction to add the objc_retainAutoreleasedReturnValue
-    // assembly markers.
-    if (Opts.Optimize)
-      EmitPasses.add(createObjCARCContractPass());
-
     bool fail = TargetMachine->addPassesToEmitFile(EmitPasses, *RawOS,
                                                    FileType, !Opts.Verify);
     if (fail) {

test/CMakeLists.txt

@@ -46,7 +46,7 @@ function(get_test_dependencies SDK result_var_name)
       swift-api-digester swift-refactor)
   if(NOT SWIFT_BUILT_STANDALONE)
     list(APPEND deps_binaries FileCheck arcmt-test c-arcmt-test c-index-test
-         clang llc llvm-cov llvm-dwarfdump llvm-link llvm-as llvm-profdata not)
+         clang llc llvm-cov llvm-dwarfdump llvm-link llvm-as llvm-dis llvm-profdata not)
   endif()
   if(SWIFT_BUILD_SOURCEKIT)
     list(APPEND deps_binaries sourcekitd-test complete-test)

test/IRGen/Inputs/StaticInline.h

@@ -3,3 +3,18 @@
 static inline NSString *staticInlineFun() {
   return [[NSLocale currentLocale] localeIdentifier];
 }
+
+static inline __attribute__((ns_returns_retained))
+NSURL *_Nullable test(NSFileManager *self_, NSURL *originalItemURL,
+                      NSURL *newItemURL, NSString *_Nullable backupItemName,
+                      NSFileManagerItemReplacementOptions options,
+                      NSError **_Nullable error) {
+  NSURL *result = nil;
+  BOOL success = [self_ replaceItemAtURL:originalItemURL
+                           withItemAtURL:newItemURL
+                          backupItemName:backupItemName
+                                 options:options
+                        resultingItemURL:&result
+                                   error:error];
+  return success ? result : nil;
+}

test/IRGen/objc_arc_contract.swift

@@ -0,0 +1,28 @@
+// Make sure that we run objc arc contract when emitting ir or bc with optimization enabled.
+
+// RUN: %empty-directory(%t)
+
+// RUN: %target-swift-frontend -import-objc-header %S/Inputs/StaticInline.h %s -emit-ir -Xllvm -disable-objc-arc-contract -parse-as-library -O | %FileCheck --check-prefix=CHECK-WITHOUT-PASS %s
+// RUN: %target-swift-frontend -import-objc-header %S/Inputs/StaticInline.h %s -emit-bc -Xllvm -disable-objc-arc-contract -parse-as-library -O -o %t/test1.bc && %llvm-dis -o - %t/test1.bc | %FileCheck --check-prefix=CHECK-WITHOUT-PASS %s
+
+// RUN: %target-swift-frontend -import-objc-header %S/Inputs/StaticInline.h %s -emit-ir -parse-as-library -O | %FileCheck --check-prefix=CHECK-WITH-PASS %s
+// RUN: %target-swift-frontend -import-objc-header %S/Inputs/StaticInline.h %s -emit-bc -parse-as-library -O -o %t/test2.bc && %llvm-dis -o - %t/test2.bc | %FileCheck --check-prefix=CHECK-WITH-PASS %s
+
+
+// REQUIRES: objc_interop
+// REQUIRES: asserts
+
+// CHECK-WITHOUT-PASS: call void (...) @clang.arc.use
+// CHECK-WITH-PASS-NOT: call void (...) @clang.arc.use
+
+import Foundation
+
+@inline(never)
+public func foo() throws {
+  let x: FileManager! = nil
+  let y = URL(string: "http://swift.org")
+  let z: URL! = nil
+  let w: String = "foo"
+  var e: NSError? = nil
+  test(x, y, z, w, .usingNewMetadataOnly, &e)
+}

test/lit.cfg

@@ -262,6 +262,7 @@ config.llvm_profdata = inferSwiftBinary('llvm-profdata')
 config.llvm_cov = inferSwiftBinary('llvm-cov')
 config.filecheck = inferSwiftBinary('FileCheck')
 config.llvm_dwarfdump = inferSwiftBinary('llvm-dwarfdump')
+config.llvm_dis = inferSwiftBinary('llvm-dis')
 config.sourcekitd_test = inferSwiftBinary('sourcekitd-test')
 config.complete_test = inferSwiftBinary('complete-test')
 config.swift_api_digester = inferSwiftBinary('swift-api-digester')
@@ -354,6 +355,7 @@ config.substitutions.append( ('%swift-format', config.swift_format) )
 config.substitutions.append( ('%llvm-link', config.llvm_link) )
 config.substitutions.append( ('%swift-llvm-opt', config.swift_llvm_opt) )
 config.substitutions.append( ('%llvm-dwarfdump', config.llvm_dwarfdump) )
+config.substitutions.append( ('%llvm-dis', config.llvm_dis) )
 
 # This must come after all substitutions containing "%swift".
 config.substitutions.append(
@@ -426,6 +428,7 @@ disallow('swift-ide-test')
 disallow('clang')
 disallow('FileCheck')
 disallow('llvm-dwarfdump')
+disallow('llvm-dis')
 
 config.substitutions.insert(0,
     ('%p',