[Backtracing] Remove support for implicit import of _Backtracing.

We're going to rename the module to Runtime, and it isn't going to be an
implicit import, so we don't need any of this.

rdar://124913332

CMakeLists.txt

@@ -695,10 +695,6 @@ option(SWIFT_IMPLICIT_CONCURRENCY_IMPORT
   "Implicitly import the Swift concurrency module"
   TRUE)
 
-option(SWIFT_IMPLICIT_BACKTRACING_IMPORT
-  "Implicitly import the Swift backtracing module"
-  FALSE)
-
 option(SWIFT_ENABLE_EXPERIMENTAL_CONCURRENCY
   "Enable build of the Swift concurrency module"
   FALSE)
@@ -865,11 +861,6 @@ if (CMAKE_Swift_COMPILER)
     SWIFT_SUPPORTS_DISABLE_IMPLICIT_STRING_PROCESSING_MODULE_IMPORT)
   message(STATUS "  Implicit 'string-processing' import: ${SWIFT_SUPPORTS_DISABLE_IMPLICIT_STRING_PROCESSING_MODULE_IMPORT}")
 
-  # Same for _Backtracing.
-  swift_supports_implicit_module("backtracing"
-    SWIFT_SUPPORTS_DISABLE_IMPLICIT_BACKTRACING_MODULE_IMPORT)
-  message(STATUS "  Implicit 'backtracing' import: ${SWIFT_SUPPORTS_DISABLE_IMPLICIT_BACKTRACING_MODULE_IMPORT}")
-
   swift_get_package_cmo_support(
     Swift_COMPILER_PACKAGE_CMO_SUPPORT)
   message(STATUS "  Package CMO: ${Swift_COMPILER_PACKAGE_CMO_SUPPORT}")

cmake/modules/AddPureSwift.cmake

@@ -28,13 +28,7 @@ function(_add_host_swift_compile_options name)
       "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -disable-implicit-string-processing-module-import>")
   endif()
 
-  # Same for backtracing
-  if (SWIFT_SUPPORTS_DISABLE_IMPLICIT_BACKTRACING_MODULE_IMPORT)
-    target_compile_options(${name} PRIVATE
-      "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -disable-implicit-backtracing-module-import>")
-  endif()
-
-   if(SWIFT_ANALYZE_CODE_COVERAGE)
+  if(SWIFT_ANALYZE_CODE_COVERAGE)
      set(_cov_flags $<$<COMPILE_LANGUAGE:Swift>:-profile-generate -profile-coverage-mapping>)
      target_compile_options(${name} PRIVATE ${_cov_flags})
      target_link_options(${name} PRIVATE ${_cov_flags})

include/swift/AST/DiagnosticsFrontend.def

@@ -188,8 +188,6 @@ WARNING(warn_implicit_concurrency_import_failed,none,
         "unable to perform implicit import of \"_Concurrency\" module: no such module found", ())
 REMARK(warn_implicit_string_processing_import_failed,none,
        "unable to perform implicit import of \"_StringProcessing\" module: no such module found", ())
-REMARK(warn_implicit_backtracing_import_failed,none,
-       "unable to perform implicit import of \"_Backtracing\" module: no such module found", ())
 
 ERROR(error_bad_module_name,none,
       "module name \"%0\" is not a valid identifier"

include/swift/Basic/LangOptions.h

@@ -421,10 +421,6 @@ namespace swift {
     /// Disable the implicit import of the _StringProcessing module.
     bool DisableImplicitStringProcessingModuleImport = false;
 
-    /// Disable the implicit import of the _Backtracing module.
-    bool DisableImplicitBacktracingModuleImport =
-        !SWIFT_IMPLICIT_BACKTRACING_IMPORT;
-
     /// Disable the implicit import of the Cxx module.
     bool DisableImplicitCxxModuleImport = false;
 

include/swift/Config.h.in

@@ -10,8 +10,6 @@
 
 #cmakedefine01 SWIFT_IMPLICIT_CONCURRENCY_IMPORT
 
-#cmakedefine01 SWIFT_IMPLICIT_BACKTRACING_IMPORT
-
 #cmakedefine01 SWIFT_ENABLE_EXPERIMENTAL_DISTRIBUTED
 
 #cmakedefine01 SWIFT_ENABLE_GLOBAL_ISEL_ARM64

include/swift/Frontend/Frontend.h

@@ -425,10 +425,6 @@ public:
   /// imported.
   bool shouldImportSwiftStringProcessing() const;
 
-  /// Whether the Swift Backtracing support library should be implicitly
-  /// imported.
-  bool shouldImportSwiftBacktracing() const;
-
   /// Whether the CXX module should be implicitly imported.
   bool shouldImportCxx() const;
 
@@ -679,14 +675,6 @@ public:
   /// i.e. if it can be found.
   bool canImportSwiftStringProcessing() const;
 
-  /// Verify that if an implicit import of the `Backtracing` module if
-  /// expected, it can actually be imported. Emit a warning, otherwise.
-  void verifyImplicitBacktracingImport();
-
-  /// Whether the Swift Backtracing support library can be imported
-  /// i.e. if it can be found.
-  bool canImportSwiftBacktracing() const;
-
   /// Whether the Cxx library can be imported
   bool canImportCxx() const;
 

include/swift/Option/FrontendOptions.td

@@ -517,14 +517,6 @@ def disable_implicit_string_processing_module_import : Flag<["-"],
   "disable-implicit-string-processing-module-import">,
   HelpText<"Disable the implicit import of the _StringProcessing module.">;
 
-def enable_implicit_backtracing_module_import : Flag<["-"],
-  "enable-implicit-backtracing-module-import">,
-  HelpText<"Enable the implicit import of the _Backtracing module.">;
-
-def disable_implicit_backtracing_module_import : Flag<["-"],
-  "disable-implicit-backtracing-module-import">,
-  HelpText<"Disable the implicit import of the _Backtracing module.">;
-
 def disable_implicit_cxx_module_import : Flag<["-"],
   "disable-implicit-cxx-module-import">,
   HelpText<"Disable the implicit import of the C++ Standard Library module.">;

include/swift/Strings.h

@@ -33,8 +33,6 @@ constexpr static const StringLiteral SWIFT_MODULE_ABI_NAME_PREFIX = "Compiler";
 constexpr static const StringLiteral SWIFT_DISTRIBUTED_NAME = "Distributed";
 /// The name of the StringProcessing module, which supports that extension.
 constexpr static const StringLiteral SWIFT_STRING_PROCESSING_NAME = "_StringProcessing";
-/// The name of the Backtracing module, which supports that extension.
-constexpr static const StringLiteral SWIFT_BACKTRACING_NAME = "_Backtracing";
 /// The name of the SwiftShims module, which contains private stdlib decls.
 constexpr static const StringLiteral SWIFT_SHIMS_NAME = "SwiftShims";
 /// The name of the CxxShim module, which contains a cxx casting utility.

lib/Frontend/CompilerInvocation.cpp

@@ -939,11 +939,6 @@ static bool ParseLangArgs(LangOptions &Opts, ArgList &Args,
   Opts.DisableImplicitCxxModuleImport |=
     Args.hasArg(OPT_disable_implicit_cxx_module_import);
 
-  Opts.DisableImplicitBacktracingModuleImport =
-    Args.hasFlag(OPT_disable_implicit_backtracing_module_import,
-                 OPT_enable_implicit_backtracing_module_import,
-                 true);
-
   if (Args.hasArg(OPT_enable_experimental_async_top_level))
     Diags.diagnose(SourceLoc(), diag::warn_flag_deprecated,
                    "-enable-experimental-async-top-level");

lib/Frontend/Frontend.cpp

@@ -1109,20 +1109,6 @@ bool CompilerInvocation::shouldImportSwiftStringProcessing() const {
         FrontendOptions::ParseInputMode::SwiftModuleInterface;
 }
 
-/// Enable Swift backtracing on a per-target basis
-static bool shouldImportSwiftBacktracingByDefault(const llvm::Triple &target) {
-  if (target.isOSDarwin() || target.isOSWindows() || target.isOSLinux())
-    return true;
-  return false;
-}
-
-bool CompilerInvocation::shouldImportSwiftBacktracing() const {
-  return shouldImportSwiftBacktracingByDefault(getLangOptions().Target) &&
-    !getLangOptions().DisableImplicitBacktracingModuleImport &&
-    getFrontendOptions().InputMode !=
-      FrontendOptions::ParseInputMode::SwiftModuleInterface;
-}
-
 bool CompilerInvocation::shouldImportCxx() const {
   // C++ Interop is disabled
   if (!getLangOptions().EnableCXXInterop)
@@ -1209,21 +1195,6 @@ bool CompilerInstance::canImportSwiftStringProcessing() const {
   return getASTContext().testImportModule(modulePath);
 }
 
-void CompilerInstance::verifyImplicitBacktracingImport() {
-  if (Invocation.shouldImportSwiftBacktracing() &&
-      !canImportSwiftBacktracing()) {
-    Diagnostics.diagnose(SourceLoc(),
-                         diag::warn_implicit_backtracing_import_failed);
-  }
-}
-
-bool CompilerInstance::canImportSwiftBacktracing() const {
-  ImportPath::Module::Builder builder(
-      getASTContext().getIdentifier(SWIFT_BACKTRACING_NAME));
-  auto modulePath = builder.get();
-  return getASTContext().testImportModule(modulePath);
-}
-
 bool CompilerInstance::canImportCxx() const {
   ImportPath::Module::Builder builder(
       getASTContext().getIdentifier(CXX_MODULE_NAME));
@@ -1321,19 +1292,6 @@ ImplicitImportInfo CompilerInstance::getImplicitImportInfo() const {
     }
   }
 
-  if (Invocation.shouldImportSwiftBacktracing()) {
-    switch (imports.StdlibKind) {
-    case ImplicitStdlibKind::Builtin:
-    case ImplicitStdlibKind::None:
-      break;
-
-    case ImplicitStdlibKind::Stdlib:
-      if (canImportSwiftBacktracing())
-        pushImport(SWIFT_BACKTRACING_NAME);
-      break;
-    }
-  }
-
   if (Invocation.getLangOptions().EnableCXXInterop) {
     if (Invocation.shouldImportCxx() && canImportCxx())
       pushImport(CXX_MODULE_NAME);

stdlib/CMakeLists.txt

@@ -228,12 +228,6 @@ swift_create_stdlib_targets("swift-test-stdlib" "" FALSE)
 swift_create_stdlib_targets("swift-libexec" "" TRUE)
 swift_create_stdlib_targets("swift-test-libexec" "" FALSE)
 
-# Check whether the Swift compiler we're using supports
-# -disable-implicit-backtracing-module-import
-include(SwiftCompilerCapability)
-
-swift_supports_implicit_module("backtracing" SWIFT_COMPILER_SUPPORTS_BACKTRACING)
-
 # FIXME: Include the toolchain directory before the public directory. Otherwise
 # the clang resource directory symlink stops installing correctly.
 add_subdirectory(toolchain)

stdlib/cmake/modules/AddSwiftStdlib.cmake

@@ -2091,11 +2091,6 @@ function(add_swift_target_library name)
   # Turn off implicit import of _StringProcessing when building libraries
   list(APPEND SWIFTLIB_SWIFT_COMPILE_FLAGS "-Xfrontend;-disable-implicit-string-processing-module-import")
 
-  # Turn off implicit import of _Backtracing when building libraries
-  if(SWIFT_COMPILER_SUPPORTS_BACKTRACING)
-    list(APPEND SWIFTLIB_SWIFT_COMPILE_FLAGS "-Xfrontend;-disable-implicit-backtracing-module-import")
-  endif()
-
   if(SWIFTLIB_IS_STDLIB AND SWIFT_STDLIB_ENABLE_PRESPECIALIZATION)
     list(APPEND SWIFTLIB_SWIFT_COMPILE_FLAGS "-Xfrontend;-prespecialize-generic-metadata")
   endif()
@@ -3126,10 +3121,6 @@ function(add_swift_target_executable name)
                       "-Xfrontend;-disable-implicit-string-processing-module-import")
   endif()
 
-  if(SWIFT_IMPLICIT_BACKTRACING_IMPORT)
-    list(APPEND SWIFTEXE_TARGET_COMPILE_FLAGS "-Xfrontend;-disable-implicit-backtracing-module-import")
-  endif()
-
   if(SWIFT_BUILD_STDLIB)
     # All Swift executables depend on the standard library.
     list(APPEND SWIFTEXE_TARGET_SWIFT_MODULE_DEPENDS Core)

test/Backtracing/SimpleBacktrace.swift

@@ -1,5 +1,5 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-build-swift %s -Xfrontend -enable-implicit-backtracing-module-import -parse-as-library -Onone -o %t/SimpleBacktrace
+// RUN: %target-build-swift %s -Xfrontend -parse-as-library -Onone -o %t/SimpleBacktrace
 // RUN: %target-codesign %t/SimpleBacktrace
 // RUN: %target-run %t/SimpleBacktrace | %FileCheck %s
 
@@ -10,6 +10,8 @@
 // UNSUPPORTED: use_os_stdlib
 // UNSUPPORTED: back_deployment_runtime
 
+import _Backtracing
+
 func level1() {
   level2()
 }

tools/SourceKit/tools/sourcekitd-test/Options.td

@@ -116,14 +116,6 @@ def disable_implicit_string_processing_module_import : Flag<["-"],
     "disable-implicit-string-processing-module-import">,
   HelpText<"Disable implicit import of the _StringProcessing module">;
 
-def enable_implicit_backtracing_module_import : Flag<["-"],
-    "enable-implicit-backtracing-module-import">,
-  HelpText<"Enable implicit import of the _Backtracing module">;
-
-def disable_implicit_backtracing_module_import : Flag<["-"],
-    "disable-implicit-backtracing-module-import">,
-  HelpText<"Disable implicit import of the _Backtracing module">;
-
 def end_pos : Separate<["-"], "end-pos">, HelpText<"line:col">;
 def end_pos_EQ : Joined<["-"], "end-pos=">, Alias<end_pos>;
 

tools/SourceKit/tools/sourcekitd-test/TestOptions.cpp

@@ -464,10 +464,6 @@ bool TestOptions::parseArgs(llvm::ArrayRef<const char *> Args) {
       DisableImplicitStringProcessingModuleImport = true;
       break;
 
-    case OPT_disable_implicit_backtracing_module_import:
-      DisableImplicitBacktracingModuleImport = true;
-      break;
-
     case OPT_UNKNOWN:
       llvm::errs() << "error: unknown argument: "
                    << InputArg->getAsString(ParsedArgs) << '\n'

tools/SourceKit/tools/sourcekitd-test/TestOptions.h

@@ -135,8 +135,6 @@ struct TestOptions {
   bool measureInstructions = false;
   bool DisableImplicitConcurrencyModuleImport = false;
   bool DisableImplicitStringProcessingModuleImport = false;
-  bool EnableImplicitBacktracingModuleImport = false;
-  bool DisableImplicitBacktracingModuleImport = false;
   std::optional<unsigned> CompletionCheckDependencyInterval;
   unsigned repeatRequest = 1;
   struct VFSFile {

tools/SourceKit/tools/sourcekitd-test/sourcekitd-test.cpp

@@ -1222,20 +1222,6 @@ static int handleTestInvocation(TestOptions Opts, TestOptions &InitOpts) {
       sourcekitd_request_array_set_string(Args, SOURCEKITD_ARRAY_APPEND,
           "-disable-implicit-string-processing-module-import");
     }
-    if (Opts.EnableImplicitBacktracingModuleImport &&
-        !compilerArgsAreClang) {
-      sourcekitd_request_array_set_string(Args, SOURCEKITD_ARRAY_APPEND,
-                                          "-Xfrontend");
-      sourcekitd_request_array_set_string(Args, SOURCEKITD_ARRAY_APPEND,
-          "-enable-implicit-backtracing-module-import");
-    }
-    if (Opts.DisableImplicitBacktracingModuleImport &&
-        !compilerArgsAreClang) {
-      sourcekitd_request_array_set_string(Args, SOURCEKITD_ARRAY_APPEND,
-                                          "-Xfrontend");
-      sourcekitd_request_array_set_string(Args, SOURCEKITD_ARRAY_APPEND,
-          "-disable-implicit-backtracing-module-import");
-    }
 
     for (auto Arg : Opts.CompilerArgs)
       sourcekitd_request_array_set_string(Args, SOURCEKITD_ARRAY_APPEND, Arg);

tools/swift-ide-test/swift-ide-test.cpp

@@ -833,16 +833,6 @@ DisableImplicitStringProcessingImport("disable-implicit-string-processing-module
                                       llvm::cl::desc("Disable implicit import of _StringProcessing module"),
                                       llvm::cl::init(false));
 
-static llvm::cl::opt<bool>
-EnableImplicitBacktracingImport("enable-implicit-backtracing-module-import",
-                                 llvm::cl::desc("Enable implicit import of _Backtracing module"),
-                                 llvm::cl::init(false));
-
-static llvm::cl::opt<bool>
-DisableImplicitBacktracingImport("disable-implicit-backtracing-module-import",
-                                 llvm::cl::desc("Disable implicit import of _Backtracing module"),
-                                 llvm::cl::init(false));
-
 static llvm::cl::opt<bool> EnableExperimentalNamedOpaqueTypes(
     "enable-experimental-named-opaque-types",
     llvm::cl::desc("Enable experimental support for named opaque result types"),
@@ -4470,13 +4460,6 @@ int main(int argc, char *argv[]) {
   if (options::DisableImplicitStringProcessingImport) {
     InitInvok.getLangOptions().DisableImplicitStringProcessingModuleImport = true;
   }
-  if (options::DisableImplicitBacktracingImport) {
-    InitInvok.getLangOptions().DisableImplicitBacktracingModuleImport = true;
-  } else if (options::EnableImplicitBacktracingImport) {
-    InitInvok.getLangOptions().DisableImplicitBacktracingModuleImport = false;
-  } else {
-    InitInvok.getLangOptions().DisableImplicitBacktracingModuleImport = true;
-  }
 
   if (options::EnableExperimentalNamedOpaqueTypes) {
     InitInvok.getLangOptions().enableFeature(Feature::NamedOpaqueTypes);