[MLIR] Add f8E4M3 IEEE 754 type

mlir/include/mlir-c/BuiltinTypes.h

@@ -89,6 +89,16 @@ MLIR_CAPI_EXPORTED bool mlirTypeIsAFloat8E5M2(MlirType type);
 /// context.
 MLIR_CAPI_EXPORTED MlirType mlirFloat8E5M2TypeGet(MlirContext ctx);
 
+/// Returns the typeID of an Float8E4M3 type.
+MLIR_CAPI_EXPORTED MlirTypeID mlirFloat8E4M3TypeGetTypeID(void);
+
+/// Checks whether the given type is an f8E4M3 type.
+MLIR_CAPI_EXPORTED bool mlirTypeIsAFloat8E4M3(MlirType type);
+
+/// Creates an f8E4M3 type in the given context. The type is owned by the
+/// context.
+MLIR_CAPI_EXPORTED MlirType mlirFloat8E4M3TypeGet(MlirContext ctx);
+
 /// Returns the typeID of an Float8E4M3FN type.
 MLIR_CAPI_EXPORTED MlirTypeID mlirFloat8E4M3FNTypeGetTypeID(void);
 

mlir/include/mlir/IR/Builders.h

@@ -61,6 +61,7 @@ class Builder {
 
   // Types.
   FloatType getFloat8E5M2Type();
+  FloatType getFloat8E4M3Type();
   FloatType getFloat8E4M3FNType();
   FloatType getFloat8E5M2FNUZType();
   FloatType getFloat8E4M3FNUZType();

mlir/include/mlir/IR/BuiltinTypes.h

@@ -56,6 +56,7 @@ class FloatType : public Type {
   static FloatType getF80(MLIRContext *ctx);
   static FloatType getF128(MLIRContext *ctx);
   static FloatType getFloat8E5M2(MLIRContext *ctx);
+  static FloatType getFloat8E4M3(MLIRContext *ctx);
   static FloatType getFloat8E4M3FN(MLIRContext *ctx);
   static FloatType getFloat8E5M2FNUZ(MLIRContext *ctx);
   static FloatType getFloat8E4M3FNUZ(MLIRContext *ctx);
@@ -405,16 +406,20 @@ inline bool BaseMemRefType::isValidElementType(Type type) {
 }
 
 inline bool FloatType::classof(Type type) {
-  return llvm::isa<Float8E5M2Type, Float8E4M3FNType, Float8E5M2FNUZType,
-                   Float8E4M3FNUZType, Float8E4M3B11FNUZType, BFloat16Type,
-                   Float16Type, FloatTF32Type, Float32Type, Float64Type,
-                   Float80Type, Float128Type>(type);
+  return llvm::isa<
+      Float8E5M2Type, Float8E4M3Type, Float8E4M3FNType, Float8E5M2FNUZType,
+      Float8E4M3FNUZType, Float8E4M3B11FNUZType, BFloat16Type, Float16Type,
+      FloatTF32Type, Float32Type, Float64Type, Float80Type, Float128Type>(type);
 }
 
 inline FloatType FloatType::getFloat8E5M2(MLIRContext *ctx) {
   return Float8E5M2Type::get(ctx);
 }
 
+inline FloatType FloatType::getFloat8E4M3(MLIRContext *ctx) {
+  return Float8E4M3Type::get(ctx);
+}
+
 inline FloatType FloatType::getFloat8E4M3FN(MLIRContext *ctx) {
   return Float8E4M3FNType::get(ctx);
 }

mlir/include/mlir/IR/BuiltinTypes.td

@@ -97,6 +97,25 @@ def Builtin_Float8E5M2 : Builtin_FloatType<"Float8E5M2", "f8E5M2"> {
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// Float8E4M3Type
+
+def Builtin_Float8E4M3 : Builtin_FloatType<"Float8E4M3", "f8E4M3"> {
+  let summary = "8-bit floating point with 3 bit mantissa";
+  let description = [{
+    An 8-bit floating point type with 1 sign bit, 4 bits exponent and 3 bits
+    mantissa. This is not a standard type as defined by IEEE-754, but it
+    follows similar conventions with the following characteristics:
+
+      * bit encoding: S1E4M3
+      * exponent bias: 7
+      * infinities: supported with exponent set to all 1s and mantissa 0s
+      * NaNs: supported with exponent bits set to all 1s and mantissa of
+        (001, 010, 011, 100, 101, 110, 111)
+      * denormals when exponent is 0
+  }];
+}
+
 //===----------------------------------------------------------------------===//
 // Float8E4M3FNType
 

mlir/include/mlir/IR/CommonTypeConstraints.td

@@ -331,6 +331,8 @@ def F8E4M3FN : Type<CPred<"$_self.isFloat8E4M3FN()">, "f8E4M3FN type">,
                BuildableType<"$_builder.getFloat8E4M3FNType()">;
 def F8E5M2 : Type<CPred<"$_self.isFloat8E5M2()">, "f8E5M2 type">,
              BuildableType<"$_builder.getFloat8E5M2Type()">;
+def F8E4M3 : Type<CPred<"$_self.isFloat8E4M3()">, "f8E4M3 type">,
+             BuildableType<"$_builder.getFloat8E4M3Type()">;
 def F8E4M3FNUZ : Type<CPred<"$_self.isFloat8E4M3FNUZ()">, "f8E4M3FNUZ type">,
                  BuildableType<"$_builder.getFloat8E4M3FNUZType()">;
 def F8E4M3B11FNUZ : Type<CPred<"$_self.isFloat8E4M3B11FNUZ()">, "f8E4M3B11FNUZ type">,

mlir/include/mlir/IR/Types.h

@@ -126,6 +126,7 @@ class Type {
   // derived types should use isa/dyn_cast.
   bool isIndex() const;
   bool isFloat8E5M2() const;
+  bool isFloat8E4M3() const;
   bool isFloat8E4M3FN() const;
   bool isFloat8E5M2FNUZ() const;
   bool isFloat8E4M3FNUZ() const;

mlir/lib/AsmParser/TokenKinds.def

@@ -95,6 +95,7 @@ TOK_KEYWORD(f32)
 TOK_KEYWORD(f64)
 TOK_KEYWORD(f80)
 TOK_KEYWORD(f8E5M2)
+TOK_KEYWORD(f8E4M3)
 TOK_KEYWORD(f8E4M3FN)
 TOK_KEYWORD(f8E5M2FNUZ)
 TOK_KEYWORD(f8E4M3FNUZ)

mlir/lib/AsmParser/TypeParser.cpp

@@ -40,6 +40,7 @@ OptionalParseResult Parser::parseOptionalType(Type &type) {
   case Token::kw_vector:
   case Token::inttype:
   case Token::kw_f8E5M2:
+  case Token::kw_f8E4M3:
   case Token::kw_f8E4M3FN:
   case Token::kw_f8E5M2FNUZ:
   case Token::kw_f8E4M3FNUZ:
@@ -304,6 +305,9 @@ Type Parser::parseNonFunctionType() {
   case Token::kw_f8E5M2:
     consumeToken(Token::kw_f8E5M2);
     return builder.getFloat8E5M2Type();
+  case Token::kw_f8E4M3:
+    consumeToken(Token::kw_f8E4M3);
+    return builder.getFloat8E4M3Type();
   case Token::kw_f8E4M3FN:
     consumeToken(Token::kw_f8E4M3FN);
     return builder.getFloat8E4M3FNType();

mlir/lib/Bindings/Python/IRTypes.cpp

@@ -143,7 +143,7 @@ class PyFloat8E4M3FNType
   }
 };
 
-/// Floating Point Type subclass - Float8M5E2Type.
+/// Floating Point Type subclass - Float8E5M2Type.
 class PyFloat8E5M2Type : public PyConcreteType<PyFloat8E5M2Type, PyFloatType> {
 public:
   static constexpr IsAFunctionTy isaFunction = mlirTypeIsAFloat8E5M2;
@@ -163,6 +163,26 @@ class PyFloat8E5M2Type : public PyConcreteType<PyFloat8E5M2Type, PyFloatType> {
   }
 };
 
+/// Floating Point Type subclass - Float8E4M3Type.
+class PyFloat8E4M3Type : public PyConcreteType<PyFloat8E4M3Type, PyFloatType> {
+public:
+  static constexpr IsAFunctionTy isaFunction = mlirTypeIsAFloat8E4M3;
+  static constexpr GetTypeIDFunctionTy getTypeIdFunction =
+      mlirFloat8E4M3TypeGetTypeID;
+  static constexpr const char *pyClassName = "Float8E4M3Type";
+  using PyConcreteType::PyConcreteType;
+
+  static void bindDerived(ClassTy &c) {
+    c.def_static(
+        "get",
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirFloat8E4M3TypeGet(context->get());
+          return PyFloat8E4M3Type(context->getRef(), t);
+        },
+        py::arg("context") = py::none(), "Create a float8_e4m3 type.");
+  }
+};
+
 /// Floating Point Type subclass - Float8E4M3FNUZ.
 class PyFloat8E4M3FNUZType
     : public PyConcreteType<PyFloat8E4M3FNUZType, PyFloatType> {
@@ -840,6 +860,7 @@ void mlir::python::populateIRTypes(py::module &m) {
   PyIndexType::bind(m);
   PyFloat8E4M3FNType::bind(m);
   PyFloat8E5M2Type::bind(m);
+  PyFloat8E4M3Type::bind(m);
   PyFloat8E4M3FNUZType::bind(m);
   PyFloat8E4M3B11FNUZType::bind(m);
   PyFloat8E5M2FNUZType::bind(m);

mlir/lib/CAPI/IR/BuiltinTypes.cpp

@@ -97,6 +97,18 @@ MlirType mlirFloat8E5M2TypeGet(MlirContext ctx) {
   return wrap(FloatType::getFloat8E5M2(unwrap(ctx)));
 }
 
+MlirTypeID mlirFloat8E4M3TypeGetTypeID() {
+  return wrap(Float8E4M3Type::getTypeID());
+}
+
+bool mlirTypeIsAFloat8E4M3(MlirType type) {
+  return unwrap(type).isFloat8E4M3();
+}
+
+MlirType mlirFloat8E4M3TypeGet(MlirContext ctx) {
+  return wrap(FloatType::getFloat8E4M3(unwrap(ctx)));
+}
+
 MlirTypeID mlirFloat8E4M3FNTypeGetTypeID() {
   return wrap(Float8E4M3FNType::getTypeID());
 }

mlir/lib/Conversion/LLVMCommon/TypeConverter.cpp

@@ -247,8 +247,9 @@ Type LLVMTypeConverter::convertIntegerType(IntegerType type) const {
 }
 
 Type LLVMTypeConverter::convertFloatType(FloatType type) const {
-  if (type.isFloat8E5M2() || type.isFloat8E4M3FN() || type.isFloat8E5M2FNUZ() ||
-      type.isFloat8E4M3FNUZ() || type.isFloat8E4M3B11FNUZ())
+  if (type.isFloat8E5M2() || type.isFloat8E4M3() || type.isFloat8E4M3FN() ||
+      type.isFloat8E5M2FNUZ() || type.isFloat8E4M3FNUZ() ||
+      type.isFloat8E4M3B11FNUZ())
     return IntegerType::get(&getContext(), type.getWidth());
   return type;
 }

mlir/lib/Dialect/Arith/Transforms/EmulateUnsupportedFloats.cpp

@@ -56,6 +56,7 @@ static std::optional<FloatType> parseFloatType(MLIRContext *ctx,
   Builder b(ctx);
   return llvm::StringSwitch<std::optional<FloatType>>(name)
       .Case("f8E5M2", b.getFloat8E5M2Type())
+      .Case("f8E4M3", b.getFloat8E4M3Type())
       .Case("f8E4M3FN", b.getFloat8E4M3FNType())
       .Case("f8E5M2FNUZ", b.getFloat8E5M2FNUZType())
       .Case("f8E4M3FNUZ", b.getFloat8E4M3FNUZType())

mlir/lib/IR/AsmPrinter.cpp

@@ -2576,6 +2576,7 @@ void AsmPrinter::Impl::printTypeImpl(Type type) {
       })
       .Case<IndexType>([&](Type) { os << "index"; })
       .Case<Float8E5M2Type>([&](Type) { os << "f8E5M2"; })
+      .Case<Float8E4M3Type>([&](Type) { os << "f8E4M3"; })
       .Case<Float8E4M3FNType>([&](Type) { os << "f8E4M3FN"; })
       .Case<Float8E5M2FNUZType>([&](Type) { os << "f8E5M2FNUZ"; })
       .Case<Float8E4M3FNUZType>([&](Type) { os << "f8E4M3FNUZ"; })

mlir/lib/IR/Builders.cpp

@@ -38,6 +38,10 @@ FloatType Builder::getFloat8E5M2Type() {
   return FloatType::getFloat8E5M2(context);
 }
 
+FloatType Builder::getFloat8E4M3Type() {
+  return FloatType::getFloat8E4M3(context);
+}
+
 FloatType Builder::getFloat8E4M3FNType() {
   return FloatType::getFloat8E4M3FN(context);
 }

mlir/lib/IR/BuiltinTypes.cpp

@@ -87,8 +87,9 @@ IntegerType IntegerType::scaleElementBitwidth(unsigned scale) {
 //===----------------------------------------------------------------------===//
 
 unsigned FloatType::getWidth() {
-  if (llvm::isa<Float8E5M2Type, Float8E4M3FNType, Float8E5M2FNUZType,
-          Float8E4M3FNUZType, Float8E4M3B11FNUZType>(*this))
+  if (llvm::isa<Float8E5M2Type, Float8E4M3Type, Float8E4M3FNType,
+                Float8E5M2FNUZType, Float8E4M3FNUZType, Float8E4M3B11FNUZType>(
+          *this))
     return 8;
   if (llvm::isa<Float16Type, BFloat16Type>(*this))
     return 16;
@@ -107,6 +108,8 @@ unsigned FloatType::getWidth() {
 const llvm::fltSemantics &FloatType::getFloatSemantics() {
   if (llvm::isa<Float8E5M2Type>(*this))
     return APFloat::Float8E5M2();
+  if (llvm::isa<Float8E4M3Type>(*this))
+    return APFloat::Float8E4M3();
   if (llvm::isa<Float8E4M3FNType>(*this))
     return APFloat::Float8E4M3FN();
   if (llvm::isa<Float8E5M2FNUZType>(*this))

mlir/lib/IR/MLIRContext.cpp

@@ -222,6 +222,7 @@ class MLIRContextImpl {
 
   /// Cached Type Instances.
   Float8E5M2Type f8E5M2Ty;
+  Float8E4M3Type f8E4M3Ty;
   Float8E4M3FNType f8E4M3FNTy;
   Float8E5M2FNUZType f8E5M2FNUZTy;
   Float8E4M3FNUZType f8E4M3FNUZTy;
@@ -312,6 +313,7 @@ MLIRContext::MLIRContext(const DialectRegistry &registry, Threading setting)
   //// Types.
   /// Floating-point Types.
   impl->f8E5M2Ty = TypeUniquer::get<Float8E5M2Type>(this);
+  impl->f8E4M3Ty = TypeUniquer::get<Float8E4M3Type>(this);
   impl->f8E4M3FNTy = TypeUniquer::get<Float8E4M3FNType>(this);
   impl->f8E5M2FNUZTy = TypeUniquer::get<Float8E5M2FNUZType>(this);
   impl->f8E4M3FNUZTy = TypeUniquer::get<Float8E4M3FNUZType>(this);
@@ -1012,6 +1014,9 @@ StorageUniquer &MLIRContext::getTypeUniquer() { return getImpl().typeUniquer; }
 Float8E5M2Type Float8E5M2Type::get(MLIRContext *context) {
   return context->getImpl().f8E5M2Ty;
 }
+Float8E4M3Type Float8E4M3Type::get(MLIRContext *context) {
+  return context->getImpl().f8E4M3Ty;
+}
 Float8E4M3FNType Float8E4M3FNType::get(MLIRContext *context) {
   return context->getImpl().f8E4M3FNTy;
 }

mlir/lib/IR/Types.cpp

@@ -35,6 +35,7 @@ Type AbstractType::replaceImmediateSubElements(Type type,
 MLIRContext *Type::getContext() const { return getDialect().getContext(); }
 
 bool Type::isFloat8E5M2() const { return llvm::isa<Float8E5M2Type>(*this); }
+bool Type::isFloat8E4M3() const { return llvm::isa<Float8E4M3Type>(*this); }
 bool Type::isFloat8E4M3FN() const { return llvm::isa<Float8E4M3FNType>(*this); }
 bool Type::isFloat8E5M2FNUZ() const {
   return llvm::isa<Float8E5M2FNUZType>(*this);

mlir/python/mlir/_mlir_libs/_mlir/ir.pyi

@@ -123,6 +123,7 @@ __all__ = [
     "Float8E4M3B11FNUZType",
     "Float8E4M3FNType",
     "Float8E4M3FNUZType",
+    "Float8E4M3Type",
     "Float8E5M2FNUZType",
     "Float8E5M2Type",
     "FloatAttr",
@@ -1575,6 +1576,19 @@ class Float8E4M3FNUZType(FloatType):
     @property
     def typeid(self) -> TypeID: ...
 
+class Float8E4M3Type(FloatType):
+    static_typeid: ClassVar[TypeID]
+    @staticmethod
+    def get(context: Optional[Context] = None) -> Float8E4M3Type:
+        """
+        Create a float8_e4m3 type.
+        """
+    @staticmethod
+    def isinstance(other: Type) -> bool: ...
+    def __init__(self, cast_from_type: Type) -> None: ...
+    @property
+    def typeid(self) -> TypeID: ...
+
 class Float8E5M2FNUZType(FloatType):
     static_typeid: ClassVar[TypeID]
     @staticmethod

mlir/python/mlir/extras/types.py

@@ -14,6 +14,7 @@
     F64Type,
     Float8E4M3B11FNUZType,
     Float8E4M3FNType,
+    Float8E4M3Type,
     Float8E5M2Type,
     FunctionType,
     IndexType,
@@ -68,6 +69,7 @@ def ui(width):
 bf16 = lambda: BF16Type.get()
 
 f8E5M2 = lambda: Float8E5M2Type.get()
+f8E4M3 = lambda: Float8E4M3Type.get()
 f8E4M3FN = lambda: Float8E4M3FNType.get()
 f8E4M3B11FNUZ = lambda: Float8E4M3B11FNUZType.get()
 

mlir/test/IR/attribute.mlir

@@ -40,6 +40,10 @@ func.func @float_attrs_pass() {
     // CHECK: float_attr = 2.000000e+00 : f8E5M2
     float_attr = 2. : f8E5M2
   } : () -> ()
+  "test.float_attrs"() {
+    // CHECK: float_attr = 2.000000e+00 : f8E4M3
+    float_attr = 2. : f8E4M3
+  } : () -> ()
   "test.float_attrs"() {
     // CHECK: float_attr = 2.000000e+00 : f8E4M3FN
     float_attr = 2. : f8E4M3FN

mlir/test/Target/LLVMIR/llvmir.mlir

@@ -39,6 +39,9 @@ llvm.mlir.global internal constant @string_const("foobar") : !llvm.array<6 x i8>
 // CHECK: @int_global_undef = internal global i64 undef
 llvm.mlir.global internal @int_global_undef() : i64
 
+// CHECK: @f8E4M3_global_as_i8 = internal global i8 60
+llvm.mlir.global internal @f8E4M3_global_as_i8(1.5 : f8E4M3) : i8
+
 // CHECK: @f8E4M3FN_global_as_i8 = internal global i8 60
 llvm.mlir.global internal @f8E4M3FN_global_as_i8(1.5 : f8E4M3FN) : i8
 

mlir/test/python/ir/builtin_types.py

@@ -113,6 +113,8 @@ def testTypeIsInstance():
 def testFloatTypeSubclasses():
     ctx = Context()
     # CHECK: True
+    print(isinstance(Type.parse("f8E4M3", ctx), FloatType))
+    # CHECK: True
     print(isinstance(Type.parse("f8E4M3FN", ctx), FloatType))
     # CHECK: True
     print(isinstance(Type.parse("f8E5M2", ctx), FloatType))
@@ -229,6 +231,8 @@ def testIndexType():
 @run
 def testFloatType():
     with Context():
+        # CHECK: float: f8E4M3
+        print("float:", Float8E4M3Type.get())
         # CHECK: float: f8E4M3FN
         print("float:", Float8E4M3FNType.get())
         # CHECK: float: f8E5M2
@@ -601,6 +605,7 @@ def testTypeIDs():
         types = [
             (IntegerType, IntegerType.get_signless(16)),
             (IndexType, IndexType.get()),
+            (Float8E4M3Type, Float8E4M3Type.get()),
             (Float8E4M3FNType, Float8E4M3FNType.get()),
             (Float8E5M2Type, Float8E5M2Type.get()),
             (Float8E4M3FNUZType, Float8E4M3FNUZType.get()),
@@ -624,6 +629,7 @@ def testTypeIDs():
 
         # CHECK: IntegerType(i16)
         # CHECK: IndexType(index)
+        # CHECK: Float8E4M3Type(f8E4M3)
         # CHECK: Float8E4M3FNType(f8E4M3FN)
         # CHECK: Float8E5M2Type(f8E5M2)
         # CHECK: Float8E4M3FNUZType(f8E4M3FNUZ)
@@ -704,6 +710,9 @@ def print_downcasted(typ):
         # CHECK: Float8E4M3B11FNUZType
         # CHECK: Float8E4M3B11FNUZType(f8E4M3B11FNUZ)
         print_downcasted(Float8E4M3B11FNUZType.get())
+        # CHECK: Float8E4M3Type
+        # CHECK: Float8E4M3Type(f8E4M3)
+        print_downcasted(Float8E4M3Type.get())
         # CHECK: Float8E4M3FNType
         # CHECK: Float8E4M3FNType(f8E4M3FN)
         print_downcasted(Float8E4M3FNType.get())