Merge pull request #59074 from slavapestov/type-reconstruction-round-trip-flag

IRGen: Add -enable/disable-round-trip-debug-types flag, on by default in asserts builds

Author: slavapestov

include/swift/AST/IRGenOptions.h

@@ -462,7 +462,7 @@ class IRGenOptions {
         PrespecializeGenericMetadata(false), UseIncrementalLLVMCodeGen(true),
         UseTypeLayoutValueHandling(true), ForceStructTypeLayouts(false),
         GenerateProfile(false), EnableDynamicReplacementChaining(false),
-        DisableRoundTripDebugTypes(false), DisableDebuggerShadowCopies(false),
+        DisableDebuggerShadowCopies(false),
         DisableConcreteTypeMetadataMangledNameAccessors(false),
         DisableStandardSubstitutionsInReflectionMangling(false),
         EnableGlobalISel(false), VirtualFunctionElimination(false),
@@ -471,7 +471,13 @@ class IRGenOptions {
         NoPreallocatedInstantiationCaches(false),
         CmdArgs(),
         SanitizeCoverage(llvm::SanitizerCoverageOptions()),
-        TypeInfoFilter(TypeInfoDumpFilter::All) {}
+        TypeInfoFilter(TypeInfoDumpFilter::All) {
+#ifndef NDEBUG
+    DisableRoundTripDebugTypes = false;
+#else
+    DisableRoundTripDebugTypes = true;
+#endif
+  }
 
   /// Appends to \p os an arbitrary string representing all options which
   /// influence the llvm compilation but are not reflected in the llvm module

include/swift/Option/FrontendOptions.td

@@ -388,6 +388,12 @@ def warn_redundant_requirements : Flag<["-"], "warn-redundant-requirements">,
 def dump_type_witness_systems : Flag<["-"], "dump-type-witness-systems">,
   HelpText<"Enables dumping type witness systems from associated type inference">;
 
+def enable_round_trip_debug_types : Flag<["-"], "enable-round-trip-debug-types">,
+  HelpText<"Enables verification of debug info mangling">;
+
+def disable_round_trip_debug_types : Flag<["-"], "disable-round-trip-debug-types">,
+  HelpText<"Disables verification of debug info mangling">;
+
 def debug_generic_signatures : Flag<["-"], "debug-generic-signatures">,
   HelpText<"Debug generic signatures">;
 

lib/Frontend/CompilerInvocation.cpp

@@ -2045,6 +2045,12 @@ static bool ParseIRGenArgs(IRGenOptions &Opts, ArgList &Args,
   if (Args.hasArg(OPT_no_clang_module_breadcrumbs))
     Opts.DisableClangModuleSkeletonCUs = true;
 
+  if (auto A = Args.getLastArg(OPT_enable_round_trip_debug_types,
+                               OPT_disable_round_trip_debug_types)) {
+    Opts.DisableRoundTripDebugTypes =
+        Args.hasArg(OPT_disable_round_trip_debug_types);
+  }
+
   if (Args.hasArg(OPT_disable_debugger_shadow_copies))
     Opts.DisableDebuggerShadowCopies = true;
 

lib/IRGen/IRGenDebugInfo.cpp

@@ -915,7 +915,6 @@ class IRGenDebugInfoImpl : public IRGenDebugInfo {
     if (!Opts.DisableRoundTripDebugTypes &&
         !Ty->getASTContext().LangOpts.EnableCXXInterop) {
       // Make sure we can reconstruct mangled types for the debugger.
-#ifndef NDEBUG
       auto &Ctx = Ty->getASTContext();
       Type Reconstructed = Demangle::getTypeForMangling(Ctx, Result);
       if (!Reconstructed) {
@@ -936,7 +935,6 @@ class IRGenDebugInfoImpl : public IRGenDebugInfo {
         Reconstructed->dump(llvm::errs());
         abort();
       }
-#endif
     }
 
     return BumpAllocatedString(Result);