MinGW-w64 SEH on Win64 support (clang part)

[Alexpux]

Summary

Patch by Martell Malone.

This patch adds MinGW-w64 SEH on Win64 support on the clang side.

See http://reviews.llvm.org/differential/revision/edit/3418/ for the LLVM part of the patch.

[rnk]

Is this useful without the LLVM change (http://reviews.llvm.org/D3418)?

It seems like a reasonable step forward for MinGW64 compatibility, but I think the commit message is off. I think most people will assume "SEH exceptions" means try { ... } except (...) { ... }, which is not what this commit covers. I'd rephrase it to talk about MinGW64 SEH support.

[Alexpux]

How change create new revision here?

[rnk]

In D3419#5, @Alexpux wrote:

How change create new revision here?

This change seems fine. If someone can rebase it and commit it that would be great.

lib/Driver/ToolChains.h

753 ↗

(On Diff #8630)

This should start with a lowercase 'u' to adhere to the coding standards in our wonderfully consistent codebase.

[Alexpux]

How commit new revision here?

[yaron.keren]

Hi Alex,

In the "Action" box above select "Commandeer Revision" and then you will become the Author.

To upload a new diff there are some options. If you want to upload the patch file, select "Create Diff" in the top-right corner and upload the updated patch. Then, attach it to this revision and it will appear here.

This patch requires lib/Driver/MinGWToolChain.cpp but you can move the three lines required in this file to the mingw toolchain patch so it won't block this one.

[Alexpux]

lib/Driver/ToolChains.h

753 ↗

(On Diff #8630)

I see that it start with uppercase 'U' for others in Toolchain.h, like "UseSjLjExceptions"

[Alexpux]

Rebase to clang 3.5.0 sources. Move Mingw part to http://reviews.llvm.org/D5268

[Alexpux]

Remove depends from mingw driver.

[asl]

LGTM

[martell]

I thought this was in the code base already?
Was this not accepted before when I submitted it?

How do I accept it as a reviewer?
Or can I only be an author

[Alexpux]

martell, I'm get remove mingw toolchain part from here to http://reviews.llvm.org/D5268.
This is not in clang codebase yet.

[rnk]

Closed by commit rL217790 (authored by @rnk).

cfe/trunk/include/clang/Basic/LangOptions.def

 LANGOPT(WritableStrings   , 1, 0, "writable string support")
 LANGOPT(ConstStrings      , 1, 0, "const-qualified string support")
 LANGOPT(LaxVectorConversions , 1, 1, "lax vector conversions")
 LANGOPT(AltiVec           , 1, 0, "AltiVec-style vector initializers")
 LANGOPT(Exceptions        , 1, 0, "exception handling")
 LANGOPT(ObjCExceptions    , 1, 0, "Objective-C exceptions")
 LANGOPT(CXXExceptions     , 1, 0, "C++ exceptions")
 LANGOPT(SjLjExceptions    , 1, 0, "setjmp-longjump exception handling")
+LANGOPT(SEHExceptions     , 1, 0, "SEH exception handling")
 LANGOPT(TraditionalCPP    , 1, 0, "traditional CPP emulation")
 LANGOPT(RTTI              , 1, 1, "run-time type information")
 LANGOPT(RTTIData          , 1, 1, "emit run-time type information data")
 LANGOPT(MSBitfields       , 1, 0, "Microsoft-compatible structure layout")
 LANGOPT(Freestanding, 1, 0, "freestanding implementation")
 LANGOPT(NoBuiltin         , 1, 0, "disable builtin functions")
 LANGOPT(NoMathBuiltin     , 1, 0, "disable math builtin functions")
 

cfe/trunk/include/clang/Driver/CC1Options.td

def main_file_name : Separate<["-"], "main-file-name">,
   HelpText<"Main file name to use for debug info">;
 
 }
 
 def fblocks_runtime_optional : Flag<["-"], "fblocks-runtime-optional">,
   HelpText<"Weakly link in the blocks runtime">;
 def fsjlj_exceptions : Flag<["-"], "fsjlj-exceptions">,
   HelpText<"Use SjLj style exceptions">;
+def fseh_exceptions : Flag<["-"], "fseh-exceptions">,
+  HelpText<"Use SEH style exceptions">;
 def split_dwarf_file : Separate<["-"], "split-dwarf-file">,
   HelpText<"File name to use for split dwarf debug info output">;
 def fno_wchar : Flag<["-"], "fno-wchar">,
   HelpText<"Disable C++ builtin type wchar_t">;
 def fconstant_string_class : Separate<["-"], "fconstant-string-class">,
   MetaVarName<"<class name>">,
   HelpText<"Specify the class to use for constant Objective-C string objects.">;
 def fobjc_arc_cxxlib_EQ : Joined<["-"], "fobjc-arc-cxxlib=">,

cfe/trunk/include/clang/Driver/ToolChain.h

public:
 
   /// UseDwarfDebugFlags - Embed the compile options to clang into the Dwarf
   /// compile unit information.
   virtual bool UseDwarfDebugFlags() const { return false; }
 
   /// UseSjLjExceptions - Does this tool chain use SjLj exceptions.
   virtual bool UseSjLjExceptions() const { return false; }
 
+  /// UseSEHExceptions - Does this tool chain use SEH exceptions.
+  virtual bool UseSEHExceptions() const { return false; }
+
   /// ComputeLLVMTriple - Return the LLVM target triple to use, after taking
   /// command line arguments into account.
   virtual std::string
   ComputeLLVMTriple(const llvm::opt::ArgList &Args,
                     types::ID InputType = types::TY_INVALID) const;
 
   /// ComputeEffectiveClangTriple - Return the Clang triple to use for this
   /// target, which may take into account the command line arguments. For

cfe/trunk/lib/CodeGen/CGException.cpp

struct EHPersonality {
     // If this is non-null, this personality requires a non-standard
     // function for rethrowing an exception after a catchall cleanup.
     // This function must have prototype void(void*).
     const char *CatchallRethrowFn;
 
     static const EHPersonality &get(const LangOptions &Lang);
     static const EHPersonality GNU_C;
     static const EHPersonality GNU_C_SJLJ;
+    static const EHPersonality GNU_C_SEH;
     static const EHPersonality GNU_ObjC;
     static const EHPersonality GNUstep_ObjC;
     static const EHPersonality GNU_ObjCXX;
     static const EHPersonality NeXT_ObjC;
     static const EHPersonality GNU_CPlusPlus;
     static const EHPersonality GNU_CPlusPlus_SJLJ;
+    static const EHPersonality GNU_CPlusPlus_SEH;
   };
 }
 
 const EHPersonality EHPersonality::GNU_C = { "__gcc_personality_v0", nullptr };
 const EHPersonality
 EHPersonality::GNU_C_SJLJ = { "__gcc_personality_sj0", nullptr };
 const EHPersonality
+EHPersonality::GNU_C_SEH = { "__gcc_personality_seh0", nullptr };
+const EHPersonality
 EHPersonality::NeXT_ObjC = { "__objc_personality_v0", nullptr };
 const EHPersonality
 EHPersonality::GNU_CPlusPlus = { "__gxx_personality_v0", nullptr };
 const EHPersonality
 EHPersonality::GNU_CPlusPlus_SJLJ = { "__gxx_personality_sj0", nullptr };
 const EHPersonality
+EHPersonality::GNU_CPlusPlus_SEH = { "__gxx_personality_seh0", nullptr };
+const EHPersonality
 EHPersonality::GNU_ObjC = {"__gnu_objc_personality_v0", "objc_exception_throw"};
 const EHPersonality
 EHPersonality::GNU_ObjCXX = { "__gnustep_objcxx_personality_v0", nullptr };
 const EHPersonality
 EHPersonality::GNUstep_ObjC = { "__gnustep_objc_personality_v0", nullptr };
 
 static const EHPersonality &getCPersonality(const LangOptions &L) {
   if (L.SjLjExceptions)
     return EHPersonality::GNU_C_SJLJ;
+  if (L.SEHExceptions)
+    return EHPersonality::GNU_C_SEH;
   return EHPersonality::GNU_C;
 }
 
 static const EHPersonality &getObjCPersonality(const LangOptions &L) {
   switch (L.ObjCRuntime.getKind()) {
   case ObjCRuntime::FragileMacOSX:
     return getCPersonality(L);
   case ObjCRuntime::MacOSX:
   case ObjCRuntime::iOS:
     return EHPersonality::NeXT_ObjC;
   case ObjCRuntime::GNUstep:
     if (L.ObjCRuntime.getVersion() >= VersionTuple(1, 7))
       return EHPersonality::GNUstep_ObjC;
     // fallthrough
   case ObjCRuntime::GCC:
   case ObjCRuntime::ObjFW:
     return EHPersonality::GNU_ObjC;
   }
   llvm_unreachable("bad runtime kind");
 }
 
 static const EHPersonality &getCXXPersonality(const LangOptions &L) {
   if (L.SjLjExceptions)
     return EHPersonality::GNU_CPlusPlus_SJLJ;
+  else if (L.SEHExceptions)
+    return EHPersonality::GNU_CPlusPlus_SEH;
   else
     return EHPersonality::GNU_CPlusPlus;
 }
 
 /// Determines the personality function to use when both C++
 /// and Objective-C exceptions are being caught.
 static const EHPersonality &getObjCXXPersonality(const LangOptions &L) {
   switch (L.ObjCRuntime.getKind()) {

cfe/trunk/lib/Driver/Tools.cpp

 
   // Handle GCC-style exception args.
   if (!C.getDriver().IsCLMode())
     addExceptionArgs(Args, InputType, getToolChain().getTriple(), KernelOrKext,
                      objcRuntime, CmdArgs);
 
   if (getToolChain().UseSjLjExceptions())
     CmdArgs.push_back("-fsjlj-exceptions");
+  else if (getToolChain().UseSEHExceptions())
+    CmdArgs.push_back("-fseh-exceptions");
 
   // C++ "sane" operator new.
   if (!Args.hasFlag(options::OPT_fassume_sane_operator_new,
                     options::OPT_fno_assume_sane_operator_new))
     CmdArgs.push_back("-fno-assume-sane-operator-new");
 
   // -fconstant-cfstrings is default, and may be subject to argument translation
   // on Darwin.

cfe/trunk/lib/Frontend/CompilerInvocation.cpp

#include "clang/Frontend/LangStandards.def"
   if (Args.hasArg(OPT_fno_lax_vector_conversions))
     Opts.LaxVectorConversions = 0;
   if (Args.hasArg(OPT_fno_threadsafe_statics))
     Opts.ThreadsafeStatics = 0;
   Opts.Exceptions = Args.hasArg(OPT_fexceptions);
   Opts.ObjCExceptions = Args.hasArg(OPT_fobjc_exceptions);
   Opts.CXXExceptions = Args.hasArg(OPT_fcxx_exceptions);
   Opts.SjLjExceptions = Args.hasArg(OPT_fsjlj_exceptions);
+  Opts.SEHExceptions = Args.hasArg(OPT_fseh_exceptions);
   Opts.TraditionalCPP = Args.hasArg(OPT_traditional_cpp);
 
   Opts.RTTI = !Args.hasArg(OPT_fno_rtti);
   Opts.RTTIData = Opts.RTTI && !Args.hasArg(OPT_fno_rtti_data);
   Opts.Blocks = Args.hasArg(OPT_fblocks);
   Opts.BlocksRuntimeOptional = Args.hasArg(OPT_fblocks_runtime_optional);
   Opts.Modules = Args.hasArg(OPT_fmodules);
   Opts.ModulesStrictDeclUse = Args.hasArg(OPT_fmodules_strict_decluse);

cfe/trunk/lib/Frontend/InitPreprocessor.cpp

#undef TOSTR2
   }
 
   if (!LangOpts.MSVCCompat && LangOpts.CXXExceptions)
     Builder.defineMacro("__EXCEPTIONS");
   if (!LangOpts.MSVCCompat && LangOpts.RTTI)
     Builder.defineMacro("__GXX_RTTI");
   if (LangOpts.SjLjExceptions)
     Builder.defineMacro("__USING_SJLJ_EXCEPTIONS__");
+  if (LangOpts.SEHExceptions)
+    Builder.defineMacro("__SEH__");
 
   if (LangOpts.Deprecated)
     Builder.defineMacro("__DEPRECATED");
 
   if (!LangOpts.MSVCCompat && LangOpts.CPlusPlus) {
     Builder.defineMacro("__GNUG__", "4");
     Builder.defineMacro("__GXX_WEAK__");
     Builder.defineMacro("__private_extern__", "extern");

cfe/trunk/test/CodeGenCXX/mingw-w64-seh-exceptions.cpp

+// RUN: %clang_cc1 %s -fexceptions -fseh-exceptions -emit-llvm -triple x86_64-w64-windows-gnu -o - | FileCheck %s
+
+extern "C" void foo();
+extern "C" void bar();
+
+struct Cleanup {
+  ~Cleanup() {
+    bar();
+  }
+};
+
+extern "C" void test() {
+  Cleanup x;
+  foo();
+}
+
+// CHECK: define void @test()
+// CHECK: invoke void @foo()
+// CHECK: landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_seh0 to i8*)