Add e8m0fnu support by conditional dtype.

jax/_src/dtypes.py

@@ -93,6 +93,7 @@ def type(self) -> type: ...
 # TODO: remove Optional when minimum ml_dtypes version >= 0.5.0
 float8_e3m4: type[np.generic] | None = None
 float8_e4m3: type[np.generic] | None = None
+float8_e8m0fnu: type[np.generic] | None = None
 float8_e4m3b11fnuz: type[np.generic] = ml_dtypes.float8_e4m3b11fnuz
 float8_e4m3fn: type[np.generic] = ml_dtypes.float8_e4m3fn
 float8_e4m3fnuz: type[np.generic] = ml_dtypes.float8_e4m3fnuz
@@ -101,6 +102,7 @@ def type(self) -> type: ...
 
 _float8_e3m4_dtype: np.dtype | None = None
 _float8_e4m3_dtype: np.dtype | None = None
+_float8_e8m0fnu_dtype: np.dtype | None = None
 _float8_e4m3b11fnuz_dtype: np.dtype = np.dtype(float8_e4m3b11fnuz)
 _float8_e4m3fn_dtype: np.dtype = np.dtype(float8_e4m3fn)
 _float8_e4m3fnuz_dtype: np.dtype = np.dtype(float8_e4m3fnuz)
@@ -155,6 +157,12 @@ def supports_inf(dtype: DTypeLike) -> bool:
   _custom_float_scalar_types.insert(0, float8_e3m4)  # type: ignore[arg-type]
   _custom_float_dtypes.insert(0, _float8_e3m4_dtype)
   _float8_dtypes.insert(0, _float8_e3m4_dtype)
+if hasattr(ml_dtypes, "float8_e8m0fnu"):
+  float8_e8m0fnu = ml_dtypes.float8_e8m0fnu
+  _float8_e8m0fnu_dtype = np.dtype(float8_e8m0fnu)
+  _custom_float_scalar_types.insert(0, float8_e8m0fnu)  # type: ignore[arg-type]
+  _custom_float_dtypes.insert(0, _float8_e8m0fnu_dtype)
+  _float8_dtypes.insert(0, _float8_e8m0fnu_dtype)
 
 # 2-bit integer support
 int2: type[np.generic] | None = None

jax/_src/export/serialization.fbs

@@ -74,6 +74,7 @@ enum DType: byte {
   f8_e4m3fnuz = 19,
   f8_e5m2 = 20,
   f8_e5m2fnuz = 21,
+  f8_e8m0fnu = 25,
 }
 
 table AbstractValue {

jax/_src/export/serialization.py

@@ -363,7 +363,8 @@ def _deserialize_pytreedef_to_pytree(p: ser_flatbuf.PyTreeDef):
   _dtype_to_dtype_kind[dtypes._float8_e3m4_dtype] = ser_flatbuf.DType.f8_e3m4
 if dtypes._float8_e4m3_dtype is not None:
   _dtype_to_dtype_kind[dtypes._float8_e4m3_dtype] = ser_flatbuf.DType.f8_e4m3
-
+if dtypes._float8_e8m0fnu_dtype is not None:
+  _dtype_to_dtype_kind[dtypes._float8_e8m0fnu_dtype] = ser_flatbuf.DType.f8_e8m0fnu
 _dtype_kind_to_dtype = {
     kind: dtype for dtype, kind in _dtype_to_dtype_kind.items()
 }

jax/_src/export/serialization_generated.py

@@ -61,6 +61,7 @@ class DType(object):
     f8_e5m2 = 20
     f8_e5m2fnuz = 21
     f0 = 22
+    f8_e8m0fnu = 25
 
 
 class ShardingKind(object):

jax/_src/interpreters/mlir.py

@@ -192,6 +192,8 @@ def _is_ir_values(x: IrValues) -> bool:
   _dtype_to_ir_type[np.dtype(dtypes.float8_e3m4)] = ir.Float8E3M4Type.get
 if dtypes.float8_e4m3 is not None:
   _dtype_to_ir_type[np.dtype(dtypes.float8_e4m3)] = ir.Float8E4M3Type.get
+if dtypes.float8_e8m0fnu is not None:
+  _dtype_to_ir_type[np.dtype(dtypes.float8_e8m0fnu)] = ir.Float8E8M0FNUType.get
 
 def dtype_to_ir_type(dtype: core.bint | np.dtype | np.generic) -> ir.Type:
   if isinstance(dtype, core.bint):

jax/_src/lax/lax.py

@@ -1021,6 +1021,8 @@ def _convert_to_hlo_attr(self, lhs_dtype: DTypeLike,
           fp8_dtypes += [np.dtype(dtypes.float8_e3m4)]
         if dtypes.float8_e4m3 is not None:
           fp8_dtypes += [np.dtype(dtypes.float8_e4m3)]
+        if dtypes.float8_e8m0fnu is not None:
+          fp8_dtypes += [np.dtype(dtypes.float8_e8m0fnu)]
         if lhs_dtype not in fp8_dtypes or rhs_dtype not in fp8_dtypes:
           raise ValueError(
               f"The dot algorithm '{self}' requires both inputs to have float8 "
@@ -3764,6 +3766,8 @@ def _is_fp8_mixed_precision_matmul(_lhs_dtypes, _rhs_dtypes):
       fp8_dtypes += (dtypes.float8_e3m4,)
     if dtypes.float8_e4m3 is not None:
       fp8_dtypes += (dtypes.float8_e4m3,)
+    if dtypes.float8_e8m0fnu is not None:
+      fp8_dtypes += (dtypes.float8_e8m0fnu,)
     return _lhs_dtypes in fp8_dtypes and _rhs_dtypes in fp8_dtypes
   del preferred_element_type  # Implied by the output aval
   lhs_aval, rhs_aval = ctx.avals_in

jax/_src/numpy/lax_numpy.py

@@ -225,6 +225,8 @@ def _make_scalar_type(np_scalar_type: type) -> _ScalarMeta:
   float8_e3m4 = _make_scalar_type(dtypes.float8_e3m4)
 if dtypes.float8_e4m3 is not None:
   float8_e4m3 = _make_scalar_type(dtypes.float8_e4m3)
+if dtypes.float8_e8m0fnu is not None:
+  float8_e8m0fnu = _make_scalar_type(dtypes.float8_e8m0fnu)
 float8_e4m3fn = _make_scalar_type(dtypes.float8_e4m3fn)
 float8_e4m3fnuz = _make_scalar_type(dtypes.float8_e4m3fnuz)
 float8_e5m2 = _make_scalar_type(dtypes.float8_e5m2)

jax/_src/public_test_util.py

@@ -97,6 +97,9 @@ def default_tolerance():
 if _dtypes.float8_e4m3 is not None:
   _default_tolerance[np.dtype(_dtypes.float8_e4m3)] = 1e-1
   default_gradient_tolerance[np.dtype(_dtypes.float8_e4m3)] = 1e-1
+if _dtypes.float8_e8m0fnu is not None:
+  _default_tolerance[np.dtype(_dtypes.float8_e8m0fnu)] = 1e0
+  default_gradient_tolerance[np.dtype(_dtypes.float8_e8m0fnu)] = 1e0
 
 def is_python_scalar(val):
   return not isinstance(val, np.generic) and isinstance(val, (bool, int, float, complex))
@@ -119,6 +122,8 @@ def _assert_numpy_allclose(a, b, atol=None, rtol=None, err_msg=''):
     custom_float_dtypes.insert(0, _dtypes.float8_e4m3)
   if _dtypes.float8_e3m4 is not None:
     custom_float_dtypes.insert(0, _dtypes.float8_e3m4)
+  if _dtypes.float8_e8m0fnu is not None:
+    custom_float_dtypes.insert(0, _dtypes.float8_e8m0fnu)
 
   def maybe_upcast(x):
     if x.dtype in custom_float_dtypes:

jax/_src/test_util.py

@@ -1385,6 +1385,8 @@ def custom_floats(self):
       float_dtypes += [_dtypes.float8_e3m4]
     if _dtypes.float8_e4m3 is not None:
       float_dtypes += [_dtypes.float8_e4m3]
+    if _dtypes.float8_e8m0fnu is not None:
+      float_dtypes += [_dtypes.float8_e8m0fnu]
     return self.supported(float_dtypes)
 
   @_cached_property

jax/numpy/__init__.py

@@ -281,6 +281,7 @@
   from jax._src.numpy.lax_numpy import (
     float8_e3m4 as float8_e3m4,
     float8_e4m3 as float8_e4m3,
+    float8_e8m0fnu as float8_e8m0fnu,
   )
 except ImportError:
   pass

tests/dtypes_test.py

@@ -68,6 +68,8 @@
   fp8_dtypes += [np.dtype(dtypes.float8_e3m4)]
 if dtypes.float8_e4m3 is not None:
   fp8_dtypes += [np.dtype(dtypes.float8_e4m3)]
+if dtypes.float8_e8m0fnu is not None:
+  fp8_dtypes += [np.dtype(dtypes.float8_e8m0fnu)]
 float_dtypes += fp8_dtypes
 custom_float_dtypes += fp8_dtypes