f6e3m2fn support

Author: sergey-kozub

llvm/unittests/ADT/APFloatTest.cpp

@@ -2084,8 +2084,14 @@ TEST(APFloatTest, getSmallestNormalized) {
   EXPECT_FALSE(test.isDenormal());
   EXPECT_TRUE(test.bitwiseIsEqual(expected));
   EXPECT_TRUE(test.isSmallestNormalized());
+
   test = APFloat::getSmallestNormalized(APFloat::Float6E3M2FN(), false);
   expected = APFloat(APFloat::Float6E3M2FN(), "0x1p-2");
+  EXPECT_FALSE(test.isNegative());
+  EXPECT_TRUE(test.isFiniteNonZero());
+  EXPECT_FALSE(test.isDenormal());
+  EXPECT_TRUE(test.bitwiseIsEqual(expected));
+  EXPECT_TRUE(test.isSmallestNormalized());
 
   test = APFloat::getSmallestNormalized(APFloat::Float4E2M1FN(), false);
   expected = APFloat(APFloat::Float4E2M1FN(), "0x1p0");

mlir/include/mlir-c/BuiltinTypes.h

@@ -149,6 +149,16 @@ MLIR_CAPI_EXPORTED bool mlirTypeIsAFloat8E3M4(MlirType type);
 /// context.
 MLIR_CAPI_EXPORTED MlirType mlirFloat8E3M4TypeGet(MlirContext ctx);
 
+/// Returns the typeID of an Float6E3M2FN type.
+MLIR_CAPI_EXPORTED MlirTypeID mlirFloat6E3M2FNTypeGetTypeID(void);
+
+/// Checks whether the given type is an f6E3M2FN type.
+MLIR_CAPI_EXPORTED bool mlirTypeIsAFloat6E3M2(MlirType type);
+
+/// Creates an f8E3M2FN type in the given context. The type is owned by the
+/// context.
+MLIR_CAPI_EXPORTED MlirType mlirFloat6E3M2FNTypeGet(MlirContext ctx);
+
 /// Returns the typeID of an BFloat16 type.
 MLIR_CAPI_EXPORTED MlirTypeID mlirBFloat16TypeGetTypeID(void);
 

mlir/include/mlir/IR/Builders.h

@@ -67,6 +67,7 @@ class Builder {
   FloatType getFloat8E4M3FNUZType();
   FloatType getFloat8E4M3B11FNUZType();
   FloatType getFloat8E3M4Type();
+  FloatType getFloat6E3M2FNType();
   FloatType getBF16Type();
   FloatType getF16Type();
   FloatType getTF32Type();

mlir/include/mlir/IR/BuiltinTypes.h

@@ -67,6 +67,7 @@ class FloatType : public Type {
   static FloatType getFloat8E4M3FNUZ(MLIRContext *ctx);
   static FloatType getFloat8E4M3B11FNUZ(MLIRContext *ctx);
   static FloatType getFloat8E3M4(MLIRContext *ctx);
+  static FloatType getFloat6E3M2FN(MLIRContext *ctx);
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast.
   static bool classof(Type type);
@@ -415,9 +416,9 @@ inline bool BaseMemRefType::isValidElementType(Type type) {
 inline bool FloatType::classof(Type type) {
   return llvm::isa<Float8E5M2Type, Float8E4M3Type, Float8E4M3FNType,
                    Float8E5M2FNUZType, Float8E4M3FNUZType,
-                   Float8E4M3B11FNUZType, Float8E3M4Type, BFloat16Type,
-                   Float16Type, FloatTF32Type, Float32Type, Float64Type,
-                   Float80Type, Float128Type>(type);
+                   Float8E4M3B11FNUZType, Float8E3M4Type, Float6E3M2FNType,
+                   BFloat16Type, Float16Type, FloatTF32Type, Float32Type,
+                   Float64Type, Float80Type, Float128Type>(type);
 }
 
 inline FloatType FloatType::getFloat8E5M2(MLIRContext *ctx) {
@@ -448,6 +449,10 @@ inline FloatType FloatType::getFloat8E3M4(MLIRContext *ctx) {
   return Float8E3M4Type::get(ctx);
 }
 
+inline FloatType FloatType::getFloat6E3M2FN(MLIRContext *ctx) {
+  return Float6E3M2FNType::get(ctx);
+}
+
 inline FloatType FloatType::getBF16(MLIRContext *ctx) {
   return BFloat16Type::get(ctx);
 }

mlir/include/mlir/IR/BuiltinTypes.td

@@ -233,6 +233,24 @@ def Builtin_Float8E3M4 : Builtin_FloatType<"Float8E3M4", "f8E3M4"> {
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// Float6E3M2FNType
+
+def Builtin_Float6E3M2FN : Builtin_FloatType<"Float6E3M2FN", "f6E3M2FN"> {
+  let summary = "6-bit floating point with 3 bits exponent and 2 bit mantissa";
+  let description = [{
+    An 6-bit floating point type with 1 sign bit, 3 bits exponent and 2 bits
+    mantissa. This is not a standard type as defined by IEEE-754, but it
+    follows similar conventions with the following characteristics:
+
+      * bit encoding: S1E3M2
+      * exponent bias: 3
+      * infinities: Not supported
+      * NaNs: Not supported
+      * denormals when exponent is 0
+  }];
+}
+
 //===----------------------------------------------------------------------===//
 // BFloat16Type
 

mlir/include/mlir/IR/CommonTypeConstraints.td

@@ -344,6 +344,8 @@ def F8E5M2FNUZ : Type<CPred<"$_self.isFloat8E5M2FNUZ()">, "f8E5M2FNUZ type">,
                  BuildableType<"$_builder.getFloat8E5M2FNUZType()">;
 def F8E3M4 : Type<CPred<"$_self.isFloat8E3M4()">, "f8E3M4 type">,
              BuildableType<"$_builder.getFloat8E3M4Type()">;
+def F6E3M2FN : Type<CPred<"$_self.isFloat6E3M2FN()">, "f6E3M2FN type">,
+               BuildableType<"$_builder.getFloat6E3M2FNType()">;
 
 def AnyComplex : Type<CPred<"::llvm::isa<::mlir::ComplexType>($_self)">,
                       "complex-type", "::mlir::ComplexType">;

mlir/include/mlir/IR/Types.h

@@ -132,6 +132,7 @@ class Type {
   bool isFloat8E4M3FNUZ() const;
   bool isFloat8E4M3B11FNUZ() const;
   bool isFloat8E3M4() const;
+  bool isFloat6E3M2FN() const;
   bool isBF16() const;
   bool isF16() const;
   bool isTF32() const;

mlir/lib/AsmParser/TokenKinds.def

@@ -101,6 +101,7 @@ TOK_KEYWORD(f8E5M2FNUZ)
 TOK_KEYWORD(f8E4M3FNUZ)
 TOK_KEYWORD(f8E4M3B11FNUZ)
 TOK_KEYWORD(f8E3M4)
+TOK_KEYWORD(f6E3M2FN)
 TOK_KEYWORD(f128)
 TOK_KEYWORD(false)
 TOK_KEYWORD(floordiv)

mlir/lib/AsmParser/TypeParser.cpp

@@ -46,6 +46,7 @@ OptionalParseResult Parser::parseOptionalType(Type &type) {
   case Token::kw_f8E4M3FNUZ:
   case Token::kw_f8E4M3B11FNUZ:
   case Token::kw_f8E3M4:
+  case Token::kw_f6E3M2FN:
   case Token::kw_bf16:
   case Token::kw_f16:
   case Token::kw_tf32:
@@ -324,6 +325,9 @@ Type Parser::parseNonFunctionType() {
   case Token::kw_f8E3M4:
     consumeToken(Token::kw_f8E3M4);
     return builder.getFloat8E3M4Type();
+  case Token::kw_f6E3M2FN:
+    consumeToken(Token::kw_f6E3M2FN);
+    return builder.getFloat6E3M2FNType();
   case Token::kw_bf16:
     consumeToken(Token::kw_bf16);
     return builder.getBF16Type();

mlir/lib/Bindings/Python/IRTypes.cpp

@@ -266,6 +266,27 @@ class PyFloat8E3M4Type : public PyConcreteType<PyFloat8E3M4Type, PyFloatType> {
   }
 };
 
+/// Floating Point Type subclass - Float6E3M2FNType.
+class PyFloat6E3M2FNType
+    : public PyConcreteType<PyFloat6E3M2FNType, PyFloatType> {
+public:
+  static constexpr IsAFunctionTy isaFunction = mlirTypeIsAFloat6E3M2FN;
+  static constexpr GetTypeIDFunctionTy getTypeIdFunction =
+      mlirFloat6E3M2FNTypeGetTypeID;
+  static constexpr const char *pyClassName = "Float6E3M2FNType";
+  using PyConcreteType::PyConcreteType;
+
+  static void bindDerived(ClassTy &c) {
+    c.def_static(
+        "get",
+        [](DefaultingPyMlirContext context) {
+          MlirType t = mlirFloat6E3M2FNTypeGet(context->get());
+          return PyFloat6E3M2FNType(context->getRef(), t);
+        },
+        py::arg("context") = py::none(), "Create a float6_e3m2fn type.");
+  }
+};
+
 /// Floating Point Type subclass - BF16Type.
 class PyBF16Type : public PyConcreteType<PyBF16Type, PyFloatType> {
 public:
@@ -885,6 +906,7 @@ void mlir::python::populateIRTypes(py::module &m) {
   PyFloat8E4M3B11FNUZType::bind(m);
   PyFloat8E5M2FNUZType::bind(m);
   PyFloat8E3M4Type::bind(m);
+  PyFloat6E3M2FNType::bind(m);
   PyBF16Type::bind(m);
   PyF16Type::bind(m);
   PyTF32Type::bind(m);