[lldb] Add support for displaying __float128 variables

Author: beetrees

lldb/bindings/python/python-extensions.swig

@@ -594,6 +594,7 @@ def is_numeric_type(basic_type):
     if basic_type == eBasicTypeFloat: return (True,True)
     if basic_type == eBasicTypeDouble: return (True,True)
     if basic_type == eBasicTypeLongDouble: return (True,True)
+    if basic_type == eBasicTypeFloat128: return (True,True)
     if basic_type == eBasicTypeFloatComplex: return (True,True)
     if basic_type == eBasicTypeDoubleComplex: return (True,True)
     if basic_type == eBasicTypeLongDoubleComplex: return (True,True)

lldb/docs/python_api_enums.rst

@@ -321,6 +321,7 @@ Format
 .. py:data:: eFormatInstruction
 .. py:data:: eFormatVoid
 .. py:data:: eFormatUnicode8
+.. py:data:: eFormatFloat128
 
 
 .. _DescriptionLevel:
@@ -1045,6 +1046,7 @@ BasicType
 .. py:data:: eBasicTypeObjCSel
 .. py:data:: eBasicTypeNullPtr
 .. py:data:: eBasicTypeOther
+.. py:data:: eBasicTypeFloat128
 
 
 .. _TraceType:

lldb/include/lldb/lldb-enumerations.h

@@ -200,6 +200,10 @@ enum Format {
   eFormatInstruction, ///< Disassemble an opcode
   eFormatVoid,        ///< Do not print this
   eFormatUnicode8,
+  eFormatFloat128, //< Disambiguate between 128-bit `long double` (which uses
+                   //< `eFormatFloat`) and `__float128` (which uses
+                   //< `eFormatFloat128`). If the value being formatted is not
+                   //< 128 bits, then this is identical to `eFormatFloat`.
   kNumFormats
 };
 
@@ -826,7 +830,8 @@ enum BasicType {
   eBasicTypeObjCClass,
   eBasicTypeObjCSel,
   eBasicTypeNullPtr,
-  eBasicTypeOther
+  eBasicTypeOther,
+  eBasicTypeFloat128
 };
 
 /// Deprecated

lldb/source/Commands/CommandObjectMemory.cpp

@@ -156,6 +156,7 @@ class OptionGroupReadMemory : public OptionGroup {
 
     case eFormatBinary:
     case eFormatFloat:
+    case eFormatFloat128:
     case eFormatOctal:
     case eFormatDecimal:
     case eFormatEnum:
@@ -1329,6 +1330,7 @@ class CommandObjectMemoryWrite : public CommandObjectParsed {
       switch (m_format_options.GetFormat()) {
       case kNumFormats:
       case eFormatFloat: // TODO: add support for floats soon
+      case eFormatFloat128:
       case eFormatCharPrintable:
       case eFormatBytesWithASCII:
       case eFormatComplex:

lldb/source/Core/DumpDataExtractor.cpp

@@ -652,6 +652,7 @@ lldb::offset_t lldb_private::DumpDataExtractor(
       }
     } break;
 
+    case eFormatFloat128:
     case eFormatFloat: {
       TargetSP target_sp;
       if (exe_scope)
@@ -665,7 +666,9 @@ lldb::offset_t lldb_private::DumpDataExtractor(
       const unsigned format_precision = 0;
 
       const llvm::fltSemantics &semantics =
-          GetFloatSemantics(target_sp, item_byte_size);
+          item_format == eFormatFloat128 && item_byte_size == 16
+              ? llvm::APFloat::IEEEquad()
+              : GetFloatSemantics(target_sp, item_byte_size);
 
       // Recalculate the byte size in case of a difference. This is possible
       // when item_byte_size is 16 (128-bit), because you could get back the

lldb/source/Core/ValueObject.cpp

@@ -1438,8 +1438,9 @@ bool ValueObject::DumpPrintableRepresentation(
           (custom_format == eFormatComplexFloat) ||
           (custom_format == eFormatDecimal) || (custom_format == eFormatHex) ||
           (custom_format == eFormatHexUppercase) ||
-          (custom_format == eFormatFloat) || (custom_format == eFormatOctal) ||
-          (custom_format == eFormatOSType) ||
+          (custom_format == eFormatFloat) ||
+          (custom_format == eFormatFloat128) ||
+          (custom_format == eFormatOctal) || (custom_format == eFormatOSType) ||
           (custom_format == eFormatUnicode16) ||
           (custom_format == eFormatUnicode32) ||
           (custom_format == eFormatUnsigned) ||

lldb/source/DataFormatters/FormatManager.cpp

@@ -72,6 +72,7 @@ static constexpr FormatInfo g_format_infos[] = {
     {eFormatInstruction, 'i', "instruction"},
     {eFormatVoid, 'v', "void"},
     {eFormatUnicode8, 'u', "unicode8"},
+    {eFormatFloat128, '\0', "float128"},
 };
 
 static_assert((sizeof(g_format_infos) / sizeof(g_format_infos[0])) ==

lldb/source/DataFormatters/VectorType.cpp

@@ -55,6 +55,8 @@ static CompilerType GetCompilerTypeForFormat(lldb::Format format,
 
   case lldb::eFormatFloat:
     return type_system->GetBasicTypeFromAST(lldb::eBasicTypeFloat);
+  case lldb::eFormatFloat128:
+    return type_system->GetBasicTypeFromAST(lldb::eBasicTypeFloat128);
 
   case lldb::eFormatHex:
   case lldb::eFormatHexUppercase:

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp

@@ -790,6 +790,8 @@ TypeSystemClang::GetBuiltinTypeForEncodingAndBitSize(Encoding encoding,
       return GetType(ast.LongDoubleTy);
     if (QualTypeMatchesBitSize(bit_size, ast, ast.HalfTy))
       return GetType(ast.HalfTy);
+    if (QualTypeMatchesBitSize(bit_size, ast, ast.Float128Ty))
+      return GetType(ast.Float128Ty);
     break;
 
   case eEncodingVector:
@@ -948,6 +950,13 @@ CompilerType TypeSystemClang::GetBuiltinTypeForDWARFEncodingAndBitSize(
     if (type_name == "long double" &&
         QualTypeMatchesBitSize(bit_size, ast, ast.LongDoubleTy))
       return GetType(ast.LongDoubleTy);
+    // As Rust currently uses `TypeSystemClang`, match `f128` here as well so it
+    // doesn't get misinterpreted as `long double` on targets where they are
+    // the same size but different formats.
+    if ((type_name == "__float128" || type_name == "_Float128" ||
+         type_name == "f128") &&
+        QualTypeMatchesBitSize(bit_size, ast, ast.Float128Ty))
+      return GetType(ast.Float128Ty);
     // Fall back to not requiring a name match
     if (QualTypeMatchesBitSize(bit_size, ast, ast.FloatTy))
       return GetType(ast.FloatTy);
@@ -957,6 +966,8 @@ CompilerType TypeSystemClang::GetBuiltinTypeForDWARFEncodingAndBitSize(
       return GetType(ast.LongDoubleTy);
     if (QualTypeMatchesBitSize(bit_size, ast, ast.HalfTy))
       return GetType(ast.HalfTy);
+    if (QualTypeMatchesBitSize(bit_size, ast, ast.Float128Ty))
+      return GetType(ast.Float128Ty);
     break;
 
   case DW_ATE_signed:
@@ -2050,6 +2061,8 @@ TypeSystemClang::GetOpaqueCompilerType(clang::ASTContext *ast,
     return ast->DoubleTy.getAsOpaquePtr();
   case eBasicTypeLongDouble:
     return ast->LongDoubleTy.getAsOpaquePtr();
+  case eBasicTypeFloat128:
+    return ast->Float128Ty.getAsOpaquePtr();
   case eBasicTypeFloatComplex:
     return ast->getComplexType(ast->FloatTy).getAsOpaquePtr();
   case eBasicTypeDoubleComplex:
@@ -4722,6 +4735,8 @@ TypeSystemClang::GetFloatTypeSemantics(size_t byte_size) {
     return ast.getFloatTypeSemantics(ast.LongDoubleTy);
   else if (bit_size == ast.getTypeSize(ast.HalfTy))
     return ast.getFloatTypeSemantics(ast.HalfTy);
+  else if (bit_size == ast.getTypeSize(ast.Float128Ty))
+    return ast.getFloatTypeSemantics(ast.Float128Ty);
   return llvm::APFloatBase::Bogus();
 }
 
@@ -5232,6 +5247,8 @@ lldb::Format TypeSystemClang::GetFormat(lldb::opaque_compiler_type_t type) {
     case clang::BuiltinType::Double:
     case clang::BuiltinType::LongDouble:
       return lldb::eFormatFloat;
+    case clang::BuiltinType::Float128:
+      return lldb::eFormatFloat128;
     default:
       return lldb::eFormatHex;
     }
@@ -5551,6 +5568,8 @@ TypeSystemClang::GetBasicTypeEnumeration(lldb::opaque_compiler_type_t type) {
         return eBasicTypeDouble;
       case clang::BuiltinType::LongDouble:
         return eBasicTypeLongDouble;
+      case clang::BuiltinType::Float128:
+        return eBasicTypeFloat128;
 
       case clang::BuiltinType::NullPtr:
         return eBasicTypeNullPtr;
@@ -6111,6 +6130,7 @@ uint32_t TypeSystemClang::GetNumPointeeChildren(clang::QualType type) {
     case clang::BuiltinType::Float:
     case clang::BuiltinType::Double:
     case clang::BuiltinType::LongDouble:
+    case clang::BuiltinType::Float128:
     case clang::BuiltinType::Dependent:
     case clang::BuiltinType::Overload:
     case clang::BuiltinType::ObjCId:
@@ -8807,6 +8827,7 @@ bool TypeSystemClang::DumpTypeValue(
         case eFormatHex:
         case eFormatHexUppercase:
         case eFormatFloat:
+        case eFormatFloat128:
         case eFormatOctal:
         case eFormatOSType:
         case eFormatUnsigned:

lldb/unittests/Core/DumpDataExtractorTest.cpp

@@ -163,6 +163,9 @@ TEST_F(DumpDataExtractorTest, Formats) {
   TestDump(0xcafef00d, lldb::Format::eFormatHex, "0xcafef00d");
   TestDump(0xcafef00d, lldb::Format::eFormatHexUppercase, "0xCAFEF00D");
   TestDump(0.456, lldb::Format::eFormatFloat, "0.45600000000000002");
+  TestDump(std::vector<uint64_t>{0x47ae147ae147ae14, 0x40011147ae147ae1},
+           lldb::Format::eFormatFloat128,
+           "4.26999999999999999999999999999999963");
   TestDump(9, lldb::Format::eFormatOctal, "011");
   // Chars packed into an integer.
   TestDump<uint32_t>(0x4C4C4442, lldb::Format::eFormatOSType, "'LLDB'");
@@ -388,6 +391,9 @@ TEST_F(DumpDataExtractorTest, ItemByteSizeErrors) {
   TestDumpWithItemByteSize(
       18, lldb::Format::eFormatFloat,
       "error: unsupported byte size (18) for float format");
+  TestDumpWithItemByteSize(
+      17, lldb::Format::eFormatFloat128,
+      "error: unsupported byte size (17) for float format");
 
   // We want sizes to exactly match one of float/double.
   TestDumpWithItemByteSize(