Merge pull request #73090 from augusto2112/mangling-abi-name-deb

Respect the module ABI name when mangling for the debugger

Author: adrian-prantl

include/swift/Strings.h

@@ -26,6 +26,9 @@ constexpr static const StringLiteral SWIFT_ONONE_SUPPORT = "SwiftOnoneSupport";
 constexpr static const StringLiteral SWIFT_CONCURRENCY_NAME = "_Concurrency";
 /// The name of the Concurrency Shims Clang module
 constexpr static const StringLiteral SWIFT_CONCURRENCY_SHIMS_NAME = "_SwiftConcurrencyShims";
+/// The unique ABI prefix that swift-syntax uses when it's built as part of the
+/// compiler.
+constexpr static const StringLiteral SWIFT_MODULE_ABI_NAME_PREFIX = "Compiler";
 /// The name of the Distributed module, which supports that extension.
 constexpr static const StringLiteral SWIFT_DISTRIBUTED_NAME = "Distributed";
 /// The name of the StringProcessing module, which supports that extension.

lib/AST/ASTMangler.cpp

@@ -2514,10 +2514,19 @@ void ASTMangler::appendModule(const ModuleDecl *module,
   // For example, if a module Foo has 'import Bar', and '-module-alias Bar=Baz'
   // was passed, the name 'Baz' will be used for mangling besides loading.
   StringRef ModName = module->getRealName().str();
-  if (RespectOriginallyDefinedIn &&
-      module->getABIName() != module->getName()) { // check if the ABI name is set
+
+  // If RespectOriginallyDefinedIn is not set, ignore the ABI name only for
+  // _Concurrency and swift-syntax (which adds "Compiler" as a prefix when
+  // building swift-syntax as part of the compiler).
+  // TODO: Mangling for the debugger should respect originally defined in, but
+  // as of right now there is not enough information in the mangled name to
+  // reconstruct AST types from mangled names when using that attribute.
+  if ((RespectOriginallyDefinedIn ||
+       (module->getName().str() != SWIFT_CONCURRENCY_NAME &&
+        !module->getABIName().str().starts_with(
+            SWIFT_MODULE_ABI_NAME_PREFIX))) &&
+      module->getABIName() != module->getName())
     ModName = module->getABIName().str();
-  }
 
   // Try the special 'swift' substitution.
   if (ModName == STDLIB_NAME) {

test/DebugInfo/module_abi_name.swift

@@ -0,0 +1,13 @@
+// RUN: %target-swift-frontend -primary-file %s -emit-ir -g -module-name=Hello -module-abi-name Goodbye -emit-ir -o - | %FileCheck %s
+
+class SomeClass {}
+// CHECK: DICompositeType(tag: DW_TAG_structure_type, name: "SomeClass",{{.*}}runtimeLang: DW_LANG_Swift, identifier: "$s7Goodbye9SomeClassCD"
+
+@available(macOS 10.13, *)
+@_originallyDefinedIn(module: "ThirdModule", OSX 10.12)
+class DefinedElsewhere {}
+// CHECK: DICompositeType(tag: DW_TAG_structure_type, name: "DefinedElsewhere",{{.*}}runtimeLang: DW_LANG_Swift, identifier: "$s7Goodbye16DefinedElsewhereCD")
+
+let v1 = SomeClass()
+let v2 = DefinedElsewhere()
+