Support for MSVS default calling convention options (/Gd, /Gz, /Gv,

/Gr), by Alexander Makarov

Patch for bug #27711
Differential Revision: http://reviews.llvm.org/D20171

llvm-svn: 269891

clang/include/clang/Basic/LangOptions.def

@@ -172,6 +172,7 @@ BENIGN_LANGOPT(AccessControl     , 1, 1, "C++ access control")
 LANGOPT(CharIsSigned      , 1, 1, "signed char")
 LANGOPT(ShortWChar        , 1, 0, "unsigned short wchar_t")
 ENUM_LANGOPT(MSPointerToMemberRepresentationMethod, PragmaMSPointersToMembersKind, 2, PPTMK_BestCase, "member-pointer representation method")
+ENUM_LANGOPT(DefaultCallingConv, DefaultCallingConvention, 3, DCC_None, "default calling convention")
 
 LANGOPT(ShortEnums        , 1, 0, "short enum types")
 
@@ -216,7 +217,6 @@ LANGOPT(ObjCSubscriptingLegacyRuntime         , 1, 0, "Subscripting support in l
 LANGOPT(FakeAddressSpaceMap , 1, 0, "OpenCL fake address space map")
 ENUM_LANGOPT(AddressSpaceMapMangling , AddrSpaceMapMangling, 2, ASMM_Target, "OpenCL address space map mangling mode")
 
-LANGOPT(MRTD , 1, 0, "-mrtd calling convention")
 BENIGN_LANGOPT(DelayedTemplateParsing , 1, 0, "delayed template parsing")
 LANGOPT(BlocksRuntimeOptional , 1, 0, "optional blocks runtime")
 

clang/include/clang/Basic/LangOptions.h

@@ -65,6 +65,14 @@ public:
     PPTMK_FullGeneralityVirtualInheritance
   };
 
+  enum DefaultCallingConvention {
+    DCC_None,
+    DCC_CDecl,
+    DCC_FastCall,
+    DCC_StdCall,
+    DCC_VectorCall
+  };
+
   enum AddrSpaceMapMangling { ASMM_Target, ASMM_On, ASMM_Off };
 
   enum MSVCMajorVersion {

clang/include/clang/Driver/CC1Options.td

@@ -610,6 +610,8 @@ def fnative_half_arguments_and_returns : Flag<["-"], "fnative-half-arguments-and
   HelpText<"Use the native __fp16 type for arguments and returns (and skip ABI-specific lowering)">;
 def fallow_half_arguments_and_returns : Flag<["-"], "fallow-half-arguments-and-returns">,
   HelpText<"Allow function arguments and returns of type half">;
+def fdefault_calling_conv_EQ : Joined<["-"], "fdefault-calling-conv=">,
+  HelpText<"Set default MS calling convention">;
 
 // C++ TSes.
 def fcoroutines : Flag<["-"], "fcoroutines">,

clang/include/clang/Driver/CLCompatOptions.td

@@ -268,6 +268,15 @@ def _SLASH_Y_ : CLFlag<"Y-">,
 def _SLASH_Fp : CLJoined<"Fp">,
   HelpText<"Set pch filename (with /Yc and /Yu)">, MetaVarName<"<filename>">;
 
+def _SLASH_Gd : CLFlag<"Gd">,
+  HelpText<"Set __cdecl as a default calling convention">;
+def _SLASH_Gr : CLFlag<"Gr">,
+  HelpText<"Set __fastcall as a default calling convention">;
+def _SLASH_Gz : CLFlag<"Gz">,
+  HelpText<"Set __stdcall as a default calling convention">;
+def _SLASH_Gv : CLFlag<"Gv">,
+  HelpText<"Set __vectorcall as a default calling convention">;
+
 // Ignored:
 
 def _SLASH_analyze_ : CLIgnoredFlag<"analyze-">;
@@ -279,7 +288,6 @@ def _SLASH_errorReport : CLIgnoredJoined<"errorReport">;
 def _SLASH_Fd : CLIgnoredJoined<"Fd">;
 def _SLASH_FC : CLIgnoredFlag<"FC">;
 def _SLASH_FS : CLIgnoredFlag<"FS">, HelpText<"Force synchronous PDB writes">;
-def _SLASH_Gd : CLIgnoredFlag<"Gd">;
 def _SLASH_GF : CLIgnoredFlag<"GF">;
 def _SLASH_GS_ : CLIgnoredFlag<"GS-">;
 def _SLASH_kernel_ : CLIgnoredFlag<"kernel-">;
@@ -324,12 +332,9 @@ def _SLASH_GL : CLFlag<"GL">;
 def _SLASH_GL_ : CLFlag<"GL-">;
 def _SLASH_Gm : CLFlag<"Gm">;
 def _SLASH_Gm_ : CLFlag<"Gm-">;
-def _SLASH_Gr : CLFlag<"Gr">;
 def _SLASH_GS : CLFlag<"GS">;
 def _SLASH_GT : CLFlag<"GT">;
 def _SLASH_Guard : CLJoined<"guard:">;
-def _SLASH_Gv : CLFlag<"Gv">;
-def _SLASH_Gz : CLFlag<"Gz">;
 def _SLASH_GZ : CLFlag<"GZ">;
 def _SLASH_H : CLFlag<"H">;
 def _SLASH_homeparams : CLFlag<"homeparams">;

clang/lib/AST/ASTContext.cpp

@@ -8618,8 +8618,25 @@ CallingConv ASTContext::getDefaultCallingConvention(bool IsVariadic,
   if (IsCXXMethod)
     return ABI->getDefaultMethodCallConv(IsVariadic);
 
-  if (LangOpts.MRTD && !IsVariadic) return CC_X86StdCall;
-
+  switch (LangOpts.getDefaultCallingConv()) {
+  case LangOptions::DCC_None:
+    break;
+  case LangOptions::DCC_CDecl:
+    return CC_C;
+  case LangOptions::DCC_FastCall:
+    if (getTargetInfo().hasFeature("sse2"))
+      return CC_X86FastCall;
+    break;
+  case LangOptions::DCC_StdCall:
+    if (!IsVariadic)
+      return CC_X86StdCall;
+    break;
+  case LangOptions::DCC_VectorCall:
+    // __vectorcall cannot be applied to variadic functions.
+    if (!IsVariadic)
+      return CC_X86VectorCall;
+    break;
+  }
   return Target->getDefaultCallingConv(TargetInfo::CCMT_Unknown);
 }
 

clang/lib/Driver/Tools.cpp

@@ -3964,7 +3964,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   if (Args.hasFlag(options::OPT_mrtd, options::OPT_mno_rtd, false))
-    CmdArgs.push_back("-mrtd");
+    CmdArgs.push_back("-fdefault-calling-conv=stdcall");
 
   if (shouldUseFramePointer(Args, getToolChain().getTriple()))
     CmdArgs.push_back("-mdisable-fp-elim");
@@ -6160,6 +6160,15 @@ void Clang::AddClangCLArgs(const ArgList &Args, types::ID InputType,
       CmdArgs.push_back("-fms-memptr-rep=virtual");
   }
 
+  if (Args.getLastArg(options::OPT__SLASH_Gd))
+     CmdArgs.push_back("-fdefault-calling-conv=cdecl");
+  else if (Args.getLastArg(options::OPT__SLASH_Gr))
+     CmdArgs.push_back("-fdefault-calling-conv=fastcall");
+  else if (Args.getLastArg(options::OPT__SLASH_Gz))
+     CmdArgs.push_back("-fdefault-calling-conv=stdcall");
+  else if (Args.getLastArg(options::OPT__SLASH_Gv))
+     CmdArgs.push_back("-fdefault-calling-conv=vectorcall");
+
   if (Arg *A = Args.getLastArg(options::OPT_vtordisp_mode_EQ))
     A->render(Args, CmdArgs);
 

clang/lib/Frontend/CompilerInvocation.cpp

@@ -1826,7 +1826,6 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   Opts.NoBitFieldTypeAlign = Args.hasArg(OPT_fno_bitfield_type_align);
   Opts.SinglePrecisionConstants = Args.hasArg(OPT_cl_single_precision_constant);
   Opts.FastRelaxedMath = Args.hasArg(OPT_cl_fast_relaxed_math);
-  Opts.MRTD = Args.hasArg(OPT_mrtd);
   Opts.HexagonQdsp6Compat = Args.hasArg(OPT_mqdsp6_compat);
   Opts.FakeAddressSpaceMap = Args.hasArg(OPT_ffake_address_space_map);
   Opts.ParseUnknownAnytype = Args.hasArg(OPT_funknown_anytype);
@@ -1903,6 +1902,49 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
     Opts.setMSPointerToMemberRepresentationMethod(InheritanceModel);
   }
 
+  // Check for MS default calling conventions being specified.
+  if (Arg *A = Args.getLastArg(OPT_fdefault_calling_conv_EQ)) {
+    LangOptions::DefaultCallingConvention DefaultCC =
+        llvm::StringSwitch<LangOptions::DefaultCallingConvention>(
+            A->getValue())
+            .Case("cdecl", LangOptions::DCC_CDecl)
+            .Case("fastcall", LangOptions::DCC_FastCall)
+            .Case("stdcall", LangOptions::DCC_StdCall)
+            .Case("vectorcall", LangOptions::DCC_VectorCall)
+            .Default(LangOptions::DCC_None);
+    if (DefaultCC == LangOptions::DCC_None)
+      Diags.Report(diag::err_drv_invalid_value)
+          << "-fdefault-calling-conv=" << A->getValue();
+
+    llvm::Triple T(TargetOpts.Triple);
+    llvm::Triple::ArchType Arch = T.getArch();
+    bool emitError = (DefaultCC == LangOptions::DCC_FastCall ||
+                  DefaultCC == LangOptions::DCC_StdCall) &&
+                 Arch != llvm::Triple::x86;
+    emitError |= DefaultCC == LangOptions::DCC_VectorCall &&
+                 !(Arch == llvm::Triple::x86 || Arch == llvm::Triple::x86_64);
+    if (emitError)
+      Diags.Report(diag::err_drv_argument_not_allowed_with)
+          << A->getSpelling() << T.getTriple();
+    else
+      Opts.setDefaultCallingConv(DefaultCC);
+  }
+
+  // -mrtd option
+  if (Arg *A = Args.getLastArg(OPT_mrtd)) {
+    if (Opts.getDefaultCallingConv() != LangOptions::DCC_None)
+      Diags.Report(diag::err_drv_argument_not_allowed_with)
+          << A->getSpelling() << "-fdefault-calling-conv";
+    else {
+      llvm::Triple T(TargetOpts.Triple);
+      if (T.getArch() != llvm::Triple::x86)
+        Diags.Report(diag::err_drv_argument_not_allowed_with)
+            << A->getSpelling() << T.getTriple();
+      else
+        Opts.setDefaultCallingConv(LangOptions::DCC_StdCall);
+    }
+  }
+
   // Check if -fopenmp is specified.
   Opts.OpenMP = Args.hasArg(options::OPT_fopenmp);
   Opts.OpenMPUseTLS =

clang/lib/Sema/SemaDeclAttr.cpp

@@ -3901,11 +3901,12 @@ bool Sema::CheckCallingConvAttr(const AttributeList &attr, CallingConv &CC,
 
     // This convention is not valid for the target. Use the default function or
     // method calling convention.
-    TargetInfo::CallingConvMethodType MT = TargetInfo::CCMT_Unknown;
-    if (FD)
-      MT = FD->isCXXInstanceMember() ? TargetInfo::CCMT_Member : 
-                                    TargetInfo::CCMT_NonMember;
-    CC = TI.getDefaultCallingConv(MT);
+    bool IsCXXMethod = false, IsVariadic = false;
+    if (FD) {
+      IsCXXMethod = FD->isCXXInstanceMember();
+      IsVariadic = FD->isVariadic();
+    }
+    CC = Context.getDefaultCallingConvention(IsVariadic, IsCXXMethod);
   }
 
   attr.setProcessingCache((unsigned) CC);

clang/test/CodeGenCXX/default_calling_conv.cpp

@@ -0,0 +1,34 @@
+// RUN: %clang_cc1 -triple i386-unknown-linux-gnu -fdefault-calling-conv=cdecl -emit-llvm -o - %s | FileCheck %s --check-prefix=CDECL --check-prefix=ALL
+// RUN: %clang_cc1 -triple i786-unknown-linux-gnu -target-feature +sse4.2 -fdefault-calling-conv=fastcall -emit-llvm -o - %s | FileCheck %s --check-prefix=FASTCALL --check-prefix=ALL
+// RUN: %clang_cc1 -triple i486-unknown-linux-gnu -fdefault-calling-conv=stdcall -emit-llvm -o - %s | FileCheck %s --check-prefix=STDCALL --check-prefix=ALL
+// RUN: %clang_cc1 -triple i486-unknown-linux-gnu -mrtd -emit-llvm -o - %s | FileCheck %s --check-prefix=STDCALL --check-prefix=ALL
+// RUN: %clang_cc1 -triple i986-unknown-linux-gnu -fdefault-calling-conv=vectorcall -emit-llvm -o - %s | FileCheck %s --check-prefix=VECTORCALL --check-prefix=ALL
+
+// CDECL: define void @_Z5test1v
+// FASTCALL: define x86_fastcallcc void @_Z5test1v
+// STDCALL: define x86_stdcallcc void @_Z5test1v
+// VECTORCALL: define x86_vectorcallcc void @_Z5test1v
+void test1() {}
+
+// ALL: define void @_Z5test2v
+void __attribute__((cdecl)) test2() {}
+
+// ALL: define x86_fastcallcc void @_Z5test3v
+void __attribute__((fastcall)) test3() {}
+
+// ALL: define x86_stdcallcc void @_Z5test4v
+void __attribute__((stdcall)) test4() {}
+
+// ALL: define  x86_vectorcallcc void @_Z5test5v
+void __attribute__((vectorcall)) test5() {}
+
+// ALL: define linkonce_odr void @_ZN1A11test_memberEv
+class A {
+public:
+  void test_member() {}
+};
+
+void test() {
+  A a;
+  a.test_member();
+}