[Clang] Add __ibm128 type to represent ppc_fp128

Currently, we have no front-end type for ppc_fp128 type in IR. PowerPC
target generates ppc_fp128 type from long double now, but there's option
(-mabi=(ieee|ibm)longdouble) to control it and we're going to do
transition from IBM extended double-double ppc_fp128 to IEEE fp128 in
the future.

This patch adds type __ibm128 which always represents ppc_fp128 in IR,
as what GCC did for that type. Without this type in Clang, compilation
will fail if compiling against future version of libstdcxx (which uses
__ibm128 in headers).

Although all operations in backend for __ibm128 is done by software,
only PowerPC enables support for it.

There's something not implemented in this commit, which can be done in
future ones:

- Literal suffix for __ibm128 type. w/W is suitable as GCC documented.
- __attribute__((mode(IF))) should be for __ibm128.
- Complex __ibm128 type.

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D93377

clang/bindings/python/clang/cindex.py

@@ -2059,6 +2059,7 @@ def __repr__(self):
 TypeKind.OBJCSEL = TypeKind(29)
 TypeKind.FLOAT128 = TypeKind(30)
 TypeKind.HALF = TypeKind(31)
+TypeKind.IBM128 = TypeKind(40)
 TypeKind.COMPLEX = TypeKind(100)
 TypeKind.POINTER = TypeKind(101)
 TypeKind.BLOCKPOINTER = TypeKind(102)

clang/include/clang-c/Index.h

@@ -3298,8 +3298,9 @@ enum CXTypeKind {
   CXType_UAccum = 37,
   CXType_ULongAccum = 38,
   CXType_BFloat16 = 39,
+  CXType_Ibm128 = 40,
   CXType_FirstBuiltin = CXType_Void,
-  CXType_LastBuiltin = CXType_BFloat16,
+  CXType_LastBuiltin = CXType_Ibm128,
 
   CXType_Complex = 100,
   CXType_Pointer = 101,

clang/include/clang/AST/ASTContext.h

@@ -1076,7 +1076,7 @@ class ASTContext : public RefCountedBase<ASTContext> {
   CanQualType SignedCharTy, ShortTy, IntTy, LongTy, LongLongTy, Int128Ty;
   CanQualType UnsignedCharTy, UnsignedShortTy, UnsignedIntTy, UnsignedLongTy;
   CanQualType UnsignedLongLongTy, UnsignedInt128Ty;
-  CanQualType FloatTy, DoubleTy, LongDoubleTy, Float128Ty;
+  CanQualType FloatTy, DoubleTy, LongDoubleTy, Float128Ty, Ibm128Ty;
   CanQualType ShortAccumTy, AccumTy,
       LongAccumTy;  // ISO/IEC JTC1 SC22 WG14 N1169 Extension
   CanQualType UnsignedShortAccumTy, UnsignedAccumTy, UnsignedLongAccumTy;

clang/include/clang/AST/BuiltinTypes.def

@@ -218,6 +218,9 @@ FLOATING_TYPE(BFloat16, BFloat16Ty)
 // '__float128'
 FLOATING_TYPE(Float128, Float128Ty)
 
+// '__ibm128'
+FLOATING_TYPE(Ibm128, Ibm128Ty)
+
 //===- Language-specific types --------------------------------------------===//
 
 // This is the type of C++0x 'nullptr'.

clang/include/clang/AST/Type.h

@@ -2003,6 +2003,7 @@ class alignas(8) Type : public ExtQualsTypeCommonBase {
   bool isFloat16Type() const;      // C11 extension ISO/IEC TS 18661
   bool isBFloat16Type() const;
   bool isFloat128Type() const;
+  bool isIbm128Type() const;
   bool isRealType() const;         // C99 6.2.5p17 (real floating + integer)
   bool isArithmeticType() const;   // C99 6.2.5p18 (integer + floating)
   bool isVoidType() const;         // C99 6.2.5p19
@@ -2550,7 +2551,7 @@ class BuiltinType : public Type {
   }
 
   bool isFloatingPoint() const {
-    return getKind() >= Half && getKind() <= Float128;
+    return getKind() >= Half && getKind() <= Ibm128;
   }
 
   /// Determines whether the given kind corresponds to a placeholder type.
@@ -6973,6 +6974,10 @@ inline bool Type::isFloat128Type() const {
   return isSpecificBuiltinType(BuiltinType::Float128);
 }
 
+inline bool Type::isIbm128Type() const {
+  return isSpecificBuiltinType(BuiltinType::Ibm128);
+}
+
 inline bool Type::isNullPtrType() const {
   return isSpecificBuiltinType(BuiltinType::NullPtr);
 }

clang/include/clang/AST/TypeLoc.h

@@ -581,10 +581,9 @@ class BuiltinTypeLoc : public ConcreteTypeLoc<UnqualTypeLoc,
 
   bool needsExtraLocalData() const {
     BuiltinType::Kind bk = getTypePtr()->getKind();
-    return (bk >= BuiltinType::UShort && bk <= BuiltinType::UInt128)
-      || (bk >= BuiltinType::Short && bk <= BuiltinType::Float128)
-      || bk == BuiltinType::UChar
-      || bk == BuiltinType::SChar;
+    return (bk >= BuiltinType::UShort && bk <= BuiltinType::UInt128) ||
+           (bk >= BuiltinType::Short && bk <= BuiltinType::Ibm128) ||
+           bk == BuiltinType::UChar || bk == BuiltinType::SChar;
   }
 
   unsigned getExtraLocalDataSize() const {

clang/include/clang/Basic/Specifiers.h

@@ -59,6 +59,7 @@ namespace clang {
     TST_float,
     TST_double,
     TST_float128,
+    TST_ibm128,
     TST_bool,         // _Bool
     TST_decimal32,    // _Decimal32
     TST_decimal64,    // _Decimal64

clang/include/clang/Basic/TargetInfo.h

@@ -64,7 +64,7 @@ struct TransferrableTargetInfo {
   unsigned char BFloat16Width, BFloat16Align;
   unsigned char FloatWidth, FloatAlign;
   unsigned char DoubleWidth, DoubleAlign;
-  unsigned char LongDoubleWidth, LongDoubleAlign, Float128Align;
+  unsigned char LongDoubleWidth, LongDoubleAlign, Float128Align, Ibm128Align;
   unsigned char LargeArrayMinWidth, LargeArrayAlign;
   unsigned char LongWidth, LongAlign;
   unsigned char LongLongWidth, LongLongAlign;
@@ -104,7 +104,7 @@ struct TransferrableTargetInfo {
   unsigned MaxTLSAlign;
 
   const llvm::fltSemantics *HalfFormat, *BFloat16Format, *FloatFormat,
-    *DoubleFormat, *LongDoubleFormat, *Float128Format;
+      *DoubleFormat, *LongDoubleFormat, *Float128Format, *Ibm128Format;
 
   ///===---- Target Data Type Query Methods -------------------------------===//
   enum IntType {
@@ -126,8 +126,10 @@ struct TransferrableTargetInfo {
     Float = 0,
     Double,
     LongDouble,
-    Float128
+    Float128,
+    Ibm128
   };
+
 protected:
   IntType SizeType, IntMaxType, PtrDiffType, IntPtrType, WCharType, WIntType,
       Char16Type, Char32Type, Int64Type, Int16Type, SigAtomicType,
@@ -200,6 +202,7 @@ class TargetInfo : public virtual TransferrableTargetInfo,
   bool HasFloat128;
   bool HasFloat16;
   bool HasBFloat16;
+  bool HasIbm128;
   bool HasStrictFP;
 
   unsigned char MaxAtomicPromoteWidth, MaxAtomicInlineWidth;
@@ -594,6 +597,9 @@ class TargetInfo : public virtual TransferrableTargetInfo,
   /// Determine whether the _BFloat16 type is supported on this target.
   virtual bool hasBFloat16Type() const { return HasBFloat16; }
 
+  /// Determine whether the __ibm128 type is supported on this target.
+  virtual bool hasIbm128Type() const { return HasIbm128; }
+
   /// Determine whether constrained floating point is supported on this target.
   virtual bool hasStrictFP() const { return HasStrictFP; }
 
@@ -672,12 +678,23 @@ class TargetInfo : public virtual TransferrableTargetInfo,
     return *Float128Format;
   }
 
+  /// getIbm128Width/Align/Format - Return the size/align/format of
+  /// '__ibm128'.
+  unsigned getIbm128Width() const { return 128; }
+  unsigned getIbm128Align() const { return Ibm128Align; }
+  const llvm::fltSemantics &getIbm128Format() const { return *Ibm128Format; }
+
   /// Return the mangled code of long double.
   virtual const char *getLongDoubleMangling() const { return "e"; }
 
   /// Return the mangled code of __float128.
   virtual const char *getFloat128Mangling() const { return "g"; }
 
+  /// Return the mangled code of __ibm128.
+  virtual const char *getIbm128Mangling() const {
+    llvm_unreachable("ibm128 not implemented on this target");
+  }
+
   /// Return the mangled code of bfloat.
   virtual const char *getBFloat16Mangling() const {
     llvm_unreachable("bfloat not implemented on this target");

clang/include/clang/Basic/TokenKinds.def

@@ -438,6 +438,7 @@ TYPE_TRAIT_2(__builtin_types_compatible_p, TypeCompatible, KEYNOCXX)
 KEYWORD(__builtin_va_arg            , KEYALL)
 KEYWORD(__extension__               , KEYALL)
 KEYWORD(__float128                  , KEYALL)
+KEYWORD(__ibm128                    , KEYALL)
 KEYWORD(__imag                      , KEYALL)
 KEYWORD(__int128                    , KEYALL)
 KEYWORD(__label__                   , KEYALL)

clang/include/clang/Sema/DeclSpec.h

@@ -275,6 +275,7 @@ class DeclSpec {
   static const TST TST_accum = clang::TST_Accum;
   static const TST TST_fract = clang::TST_Fract;
   static const TST TST_float128 = clang::TST_float128;
+  static const TST TST_ibm128 = clang::TST_ibm128;
   static const TST TST_bool = clang::TST_bool;
   static const TST TST_decimal32 = clang::TST_decimal32;
   static const TST TST_decimal64 = clang::TST_decimal64;

clang/include/clang/Serialization/ASTBitCodes.h

@@ -1064,6 +1064,9 @@ enum PredefinedTypeIDs {
   /// \brief The '__bf16' type
   PREDEF_TYPE_BFLOAT16_ID = 73,
 
+  /// \brief The '__ibm128' type
+  PREDEF_TYPE_IBM128_ID = 74,
+
 /// OpenCL image types with auto numeration
 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix)                   \
   PREDEF_TYPE_##Id##_ID,

clang/lib/AST/ASTContext.cpp

@@ -101,7 +101,14 @@
 using namespace clang;
 
 enum FloatingRank {
-  BFloat16Rank, Float16Rank, HalfRank, FloatRank, DoubleRank, LongDoubleRank, Float128Rank
+  BFloat16Rank,
+  Float16Rank,
+  HalfRank,
+  FloatRank,
+  DoubleRank,
+  LongDoubleRank,
+  Float128Rank,
+  Ibm128Rank
 };
 
 /// \returns location that is relevant when searching for Doc comments related
@@ -1307,6 +1314,9 @@ void ASTContext::InitBuiltinTypes(const TargetInfo &Target,
   // GNU extension, __float128 for IEEE quadruple precision
   InitBuiltinType(Float128Ty,          BuiltinType::Float128);
 
+  // __ibm128 for IBM extended precision
+  InitBuiltinType(Ibm128Ty, BuiltinType::Ibm128);
+
   // C11 extension ISO/IEC TS 18661-3
   InitBuiltinType(Float16Ty,           BuiltinType::Float16);
 
@@ -1703,6 +1713,8 @@ const llvm::fltSemantics &ASTContext::getFloatTypeSemantics(QualType T) const {
     return Target->getHalfFormat();
   case BuiltinType::Float:      return Target->getFloatFormat();
   case BuiltinType::Double:     return Target->getDoubleFormat();
+  case BuiltinType::Ibm128:
+    return Target->getIbm128Format();
   case BuiltinType::LongDouble:
     if (getLangOpts().OpenMP && getLangOpts().OpenMPIsDevice)
       return AuxTarget->getLongDoubleFormat();
@@ -2129,6 +2141,10 @@ TypeInfo ASTContext::getTypeInfoImpl(const Type *T) const {
       Width = Target->getDoubleWidth();
       Align = Target->getDoubleAlign();
       break;
+    case BuiltinType::Ibm128:
+      Width = Target->getIbm128Width();
+      Align = Target->getIbm128Align();
+      break;
     case BuiltinType::LongDouble:
       if (getLangOpts().OpenMP && getLangOpts().OpenMPIsDevice &&
           (Target->getLongDoubleWidth() != AuxTarget->getLongDoubleWidth() ||
@@ -6309,6 +6325,7 @@ static FloatingRank getFloatingRank(QualType T) {
   case BuiltinType::LongDouble: return LongDoubleRank;
   case BuiltinType::Float128:   return Float128Rank;
   case BuiltinType::BFloat16:   return BFloat16Rank;
+  case BuiltinType::Ibm128:     return Ibm128Rank;
   }
 }
 
@@ -6324,6 +6341,7 @@ QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
     case BFloat16Rank: llvm_unreachable("Complex bfloat16 is not supported");
     case Float16Rank:
     case HalfRank: llvm_unreachable("Complex half is not supported");
+    case Ibm128Rank: llvm_unreachable("Complex __ibm128 is not supported");
     case FloatRank:      return FloatComplexTy;
     case DoubleRank:     return DoubleComplexTy;
     case LongDoubleRank: return LongDoubleComplexTy;
@@ -6340,6 +6358,8 @@ QualType ASTContext::getFloatingTypeOfSizeWithinDomain(QualType Size,
   case DoubleRank:     return DoubleTy;
   case LongDoubleRank: return LongDoubleTy;
   case Float128Rank:   return Float128Ty;
+  case Ibm128Rank:
+    return Ibm128Ty;
   }
   llvm_unreachable("getFloatingRank(): illegal value for rank");
 }
@@ -7315,6 +7335,7 @@ static char getObjCEncodingForPrimitiveType(const ASTContext *C,
     case BuiltinType::BFloat16:
     case BuiltinType::Float16:
     case BuiltinType::Float128:
+    case BuiltinType::Ibm128:
     case BuiltinType::Half:
     case BuiltinType::ShortAccum:
     case BuiltinType::Accum:
@@ -11250,6 +11271,8 @@ QualType ASTContext::getRealTypeForBitwidth(unsigned DestWidth,
     return LongDoubleTy;
   case TargetInfo::Float128:
     return Float128Ty;
+  case TargetInfo::Ibm128:
+    return Ibm128Ty;
   case TargetInfo::NoFloat:
     return {};
   }

clang/lib/AST/ItaniumMangle.cpp

@@ -2860,6 +2860,7 @@ void CXXNameMangler::mangleType(const BuiltinType *T) {
   //                 ::= d  # double
   //                 ::= e  # long double, __float80
   //                 ::= g  # __float128
+  //                 ::= g  # __ibm128
   // UNSUPPORTED:    ::= Dd # IEEE 754r decimal floating point (64 bits)
   // UNSUPPORTED:    ::= De # IEEE 754r decimal floating point (128 bits)
   // UNSUPPORTED:    ::= Df # IEEE 754r decimal floating point (32 bits)
@@ -2988,6 +2989,11 @@ void CXXNameMangler::mangleType(const BuiltinType *T) {
     Out << TI->getBFloat16Mangling();
     break;
   }
+  case BuiltinType::Ibm128: {
+    const TargetInfo *TI = &getASTContext().getTargetInfo();
+    Out << TI->getIbm128Mangling();
+    break;
+  }
   case BuiltinType::NullPtr:
     Out << "Dn";
     break;

clang/lib/AST/MicrosoftMangle.cpp

@@ -2466,6 +2466,7 @@ void MicrosoftCXXNameMangler::mangleType(const BuiltinType *T, Qualifiers,
   case BuiltinType::SatUFract:
   case BuiltinType::SatULongFract:
   case BuiltinType::BFloat16:
+  case BuiltinType::Ibm128:
   case BuiltinType::Float128: {
     DiagnosticsEngine &Diags = Context.getDiags();
     unsigned DiagID = Diags.getCustomDiagID(

clang/lib/AST/NSAPI.cpp

@@ -456,6 +456,7 @@ NSAPI::getNSNumberFactoryMethodKind(QualType T) const {
   case BuiltinType::UInt128:
   case BuiltinType::Float16:
   case BuiltinType::Float128:
+  case BuiltinType::Ibm128:
   case BuiltinType::NullPtr:
   case BuiltinType::ObjCClass:
   case BuiltinType::ObjCId:

clang/lib/AST/PrintfFormatString.cpp

@@ -755,6 +755,7 @@ bool PrintfSpecifier::fixType(QualType QT, const LangOptions &LangOpt,
   case BuiltinType::BFloat16:
   case BuiltinType::Float16:
   case BuiltinType::Float128:
+  case BuiltinType::Ibm128:
   case BuiltinType::ShortAccum:
   case BuiltinType::Accum:
   case BuiltinType::LongAccum:

clang/lib/AST/StmtPrinter.cpp

@@ -1183,6 +1183,7 @@ static void PrintFloatingLiteral(raw_ostream &OS, FloatingLiteral *Node,
   switch (Node->getType()->castAs<BuiltinType>()->getKind()) {
   default: llvm_unreachable("Unexpected type for float literal!");
   case BuiltinType::Half:       break; // FIXME: suffix?
+  case BuiltinType::Ibm128:     break; // FIXME: No suffix for ibm128 literal
   case BuiltinType::Double:     break; // no suffix.
   case BuiltinType::Float16:    OS << "F16"; break;
   case BuiltinType::Float:      OS << 'F'; break;

clang/lib/AST/Type.cpp

@@ -2097,7 +2097,7 @@ bool Type::hasUnsignedIntegerRepresentation() const {
 bool Type::isFloatingType() const {
   if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
     return BT->getKind() >= BuiltinType::Half &&
-           BT->getKind() <= BuiltinType::Float128;
+           BT->getKind() <= BuiltinType::Ibm128;
   if (const auto *CT = dyn_cast<ComplexType>(CanonicalType))
     return CT->getElementType()->isFloatingType();
   return false;
@@ -2119,7 +2119,7 @@ bool Type::isRealFloatingType() const {
 bool Type::isRealType() const {
   if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
     return BT->getKind() >= BuiltinType::Bool &&
-           BT->getKind() <= BuiltinType::Float128;
+           BT->getKind() <= BuiltinType::Ibm128;
   if (const auto *ET = dyn_cast<EnumType>(CanonicalType))
       return ET->getDecl()->isComplete() && !ET->getDecl()->isScoped();
   return isExtIntType();
@@ -2128,7 +2128,7 @@ bool Type::isRealType() const {
 bool Type::isArithmeticType() const {
   if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
     return BT->getKind() >= BuiltinType::Bool &&
-           BT->getKind() <= BuiltinType::Float128 &&
+           BT->getKind() <= BuiltinType::Ibm128 &&
            BT->getKind() != BuiltinType::BFloat16;
   if (const auto *ET = dyn_cast<EnumType>(CanonicalType))
     // GCC allows forward declaration of enum types (forbid by C99 6.7.2.3p2).
@@ -3030,6 +3030,8 @@ StringRef BuiltinType::getName(const PrintingPolicy &Policy) const {
     return "_Float16";
   case Float128:
     return "__float128";
+  case Ibm128:
+    return "__ibm128";
   case WChar_S:
   case WChar_U:
     return Policy.MSWChar ? "__wchar_t" : "wchar_t";

clang/lib/AST/TypeLoc.cpp

@@ -351,6 +351,7 @@ TypeSpecifierType BuiltinTypeLoc::getWrittenTypeSpec() const {
   case BuiltinType::LongDouble:
   case BuiltinType::Float16:
   case BuiltinType::Float128:
+  case BuiltinType::Ibm128:
   case BuiltinType::ShortAccum:
   case BuiltinType::Accum:
   case BuiltinType::LongAccum:

clang/lib/Basic/TargetInfo.cpp

@@ -34,6 +34,7 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
   NoAsmVariants = false;
   HasLegalHalfType = false;
   HasFloat128 = false;
+  HasIbm128 = false;
   HasFloat16 = false;
   HasBFloat16 = false;
   HasStrictFP = false;
@@ -83,6 +84,7 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
   LongDoubleWidth = 64;
   LongDoubleAlign = 64;
   Float128Align = 128;
+  Ibm128Align = 128;
   LargeArrayMinWidth = 0;
   LargeArrayAlign = 0;
   MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 0;
@@ -113,6 +115,7 @@ TargetInfo::TargetInfo(const llvm::Triple &T) : TargetOpts(), Triple(T) {
   DoubleFormat = &llvm::APFloat::IEEEdouble();
   LongDoubleFormat = &llvm::APFloat::IEEEdouble();
   Float128Format = &llvm::APFloat::IEEEquad();
+  Ibm128Format = &llvm::APFloat::PPCDoubleDouble();
   MCountName = "mcount";
   UserLabelPrefix = "_";
   RegParmMax = 0;