Add float8_e4m3 and float8_e3m4 types support

jax/_src/dtypes.py

@@ -90,12 +90,17 @@ def type(self) -> type: ...
 
 
 # fp8 support
+# 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_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
 float8_e5m2: type[np.generic] = ml_dtypes.float8_e5m2
 float8_e5m2fnuz: type[np.generic] = ml_dtypes.float8_e5m2fnuz
 
+_float8_e3m4_dtype: np.dtype | None = None
+_float8_e4m3_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)
@@ -137,6 +142,20 @@ def supports_inf(dtype: DTypeLike) -> bool:
  _float8_e5m2fnuz_dtype,
 ]
 
+# TODO: remove the if statements below when minimum ml_dtypes version >= 0.5.0
+if hasattr(ml_dtypes, "float8_e4m3"):
+ float8_e4m3 = ml_dtypes.float8_e4m3
+ _float8_e4m3_dtype = np.dtype(float8_e4m3)
+ _custom_float_scalar_types.insert(0, float8_e4m3) # type: ignore[arg-type]
+ _custom_float_dtypes.insert(0, _float8_e4m3_dtype) # type: ignore[arg-type]
+ _float8_dtypes.insert(0, _float8_e4m3_dtype) # type: ignore[arg-type]
+if hasattr(ml_dtypes, "float8_e3m4"):
+ float8_e3m4 = ml_dtypes.float8_e3m4
+ _float8_e3m4_dtype = np.dtype(float8_e3m4)
+ _custom_float_scalar_types.insert(0, float8_e3m4) # type: ignore[arg-type]
+ _custom_float_dtypes.insert(0, _float8_e3m4_dtype) # type: ignore[arg-type]
+ _float8_dtypes.insert(0, _float8_e3m4_dtype) # type: ignore[arg-type]
+
 # 2-bit integer support
 int2: type[np.generic] | None = None
 uint2: type[np.generic] | None = None

jax/_src/export/serialization.fbs

@@ -64,6 +64,8 @@ enum DType: byte {
  i4 = 15,
  ui4 = 16,
 
+ f8_e3m4 = 24,
+ f8_e4m3 = 23,
  f8_e4m3b11fnuz = 17,
  f8_e4m3fn = 18,
  f8_e4m3fnuz = 19,

jax/_src/export/serialization.py

@@ -324,6 +324,10 @@ def _deserialize_pytreedef_to_pytree(p: ser_flatbuf.PyTreeDef):
  dtypes._float8_e5m2fnuz_dtype: ser_flatbuf.DType.f8_e5m2fnuz,
 }
 
+if dtypes._float8_e3m4_dtype is not None:
+ _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
 
 _dtype_kind_to_dtype = {
  kind: dtype for dtype, kind in _dtype_to_dtype_kind.items()

jax/_src/export/serialization_generated.py

@@ -52,6 +52,8 @@ class DType:
  bf16 = 14
  i4 = 15
  ui4 = 16
+ f8_e3m4 = 24
+ f8_e4m3 = 23
  f8_e4m3b11fnuz = 17
  f8_e4m3fn = 18
  f8_e4m3fnuz = 19

jax/_src/interpreters/mlir.py

@@ -186,13 +186,13 @@ def _is_ir_values(x: IrValues) -> bool:
 
 if dtypes.int2 is not None:
  assert dtypes.uint2 is not None
- _dtype_to_ir_type[np.dtype(dtypes.int2)] = partial(
- ir.IntegerType.get_signless, 2
- )
- _dtype_to_ir_type[np.dtype(dtypes.uint2)] = partial(
- ir.IntegerType.get_unsigned, 2
- )
+ _dtype_to_ir_type[np.dtype(dtypes.int2)] = partial(ir.IntegerType.get_signless, 2)
+ _dtype_to_ir_type[np.dtype(dtypes.uint2)] = partial(ir.IntegerType.get_unsigned, 2)
 
+if dtypes.float8_e3m4 is not None:
+ _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
 
 def dtype_to_ir_type(dtype: core.bint | np.dtype | np.generic) -> ir.Type:
  if isinstance(dtype, core.bint):

jax/_src/lax/lax.py

@@ -831,11 +831,17 @@ def _convert_to_hlo_attr(self, lhs_dtype: DTypeLike,
 
  if self in (DotAlgorithm.Preset.ANY_F8_ANY_F8_F32,
  DotAlgorithm.Preset.ANY_F8_ANY_F8_F32_FAST_ACCUM):
- fp8_dtypes = (np.dtype(dtypes.float8_e4m3b11fnuz),
- np.dtype(dtypes.float8_e4m3fn),
- np.dtype(dtypes.float8_e4m3fnuz),
- np.dtype(dtypes.float8_e5m2),
- np.dtype(dtypes.float8_e5m2fnuz))
+ fp8_dtypes = [
+ np.dtype(dtypes.float8_e4m3b11fnuz),
+ np.dtype(dtypes.float8_e4m3fn),
+ np.dtype(dtypes.float8_e4m3fnuz),
+ np.dtype(dtypes.float8_e5m2),
+ np.dtype(dtypes.float8_e5m2fnuz),
+ ]
+ if dtypes.float8_e3m4 is not None:
+ fp8_dtypes += [np.dtype(dtypes.float8_e3m4)]
+ if dtypes.float8_e4m3 is not None:
+ fp8_dtypes += [np.dtype(dtypes.float8_e4m3)]
  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 "
@@ -3386,9 +3392,18 @@ def _dot_general_lower(ctx, lhs, rhs, *, dimension_numbers,
  transpose_algorithm: DotTransposeAlgorithm | None = None,
  platform: str = "default"):
  del transpose_algorithm # unused
+
  def _is_fp8_mixed_precision_matmul(_lhs_dtypes, _rhs_dtypes):
- fp8_dtypes = (dtypes.float8_e4m3fn, dtypes.float8_e5m2,
- dtypes.float8_e5m2fnuz, dtypes.float8_e4m3fnuz)
+ fp8_dtypes = [
+ dtypes.float8_e4m3fn,
+ dtypes.float8_e5m2,
+ dtypes.float8_e5m2fnuz,
+ dtypes.float8_e4m3fnuz,
+ ]
+ if dtypes.float8_e3m4 is not None:
+ fp8_dtypes += [dtypes.float8_e3m4]
+ if dtypes.float8_e4m3 is not None:
+ fp8_dtypes += [dtypes.float8_e4m3]
  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

@@ -211,6 +211,10 @@ def _make_scalar_type(np_scalar_type: type) -> _ScalarMeta:
 int16 = _make_scalar_type(np.int16)
 int32 = _make_scalar_type(np.int32)
 int64 = _make_scalar_type(np.int64)
+if dtypes.float8_e3m4 is not None:
+ float8_e3m4 = _make_scalar_type(dtypes.float8_e3m4)
+if dtypes.float8_e4m3 is not None:
+ float8_e4m3 = _make_scalar_type(dtypes.float8_e4m3)
 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

@@ -90,6 +90,14 @@ def default_tolerance():
  np.dtype(np.complex128): 1e-5,
 }
 
+# TODO: make this unconditional when ml_dtypes>=0.5.0 is required
+if _dtypes.float8_e3m4 is not None:
+ _default_tolerance[np.dtype(_dtypes.float8_e3m4)] = 1e-1
+ default_gradient_tolerance[np.dtype(_dtypes.float8_e3m4)] = 1e-1
+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
+
 def is_python_scalar(val):
  return not isinstance(val, np.generic) and isinstance(val, (bool, int, float, complex))
 
@@ -106,6 +114,12 @@ def _assert_numpy_allclose(a, b, atol=None, rtol=None, err_msg=''):
  _dtypes.float8_e5m2fnuz,
  _dtypes.bfloat16,
  ]
+
+ if _dtypes.float8_e4m3 is not None:
+ custom_float_dtypes.insert(0, _dtypes.float8_e4m3) # type: ignore[arg-type]
+ if _dtypes.float8_e3m4 is not None:
+ custom_float_dtypes.insert(0, _dtypes.float8_e3m4) # type: ignore[arg-type]
+
  def maybe_upcast(x):
  if x.dtype in custom_float_dtypes:
  return x.astype(np.float32)

jax/_src/test_util.py

@@ -1433,10 +1433,19 @@ def supported(self, dtypes):
 
  @_cached_property
  def custom_floats(self):
- return [np.dtype(t) for t in [
- _dtypes.bfloat16, _dtypes.float8_e4m3b11fnuz,
- _dtypes.float8_e4m3fn, _dtypes.float8_e4m3fnuz,
- _dtypes.float8_e5m2, _dtypes.float8_e5m2fnuz]]
+ float_dtypes = [
+ _dtypes.bfloat16,
+ _dtypes.float8_e4m3b11fnuz,
+ _dtypes.float8_e4m3fn,
+ _dtypes.float8_e4m3fnuz,
+ _dtypes.float8_e5m2,
+ _dtypes.float8_e5m2fnuz,
+ ]
+ if _dtypes.float8_e3m4 is not None:
+ float_dtypes += [_dtypes.float8_e3m4]
+ if _dtypes.float8_e4m3 is not None:
+ float_dtypes += [_dtypes.float8_e4m3]
+ return [np.dtype(t) for t in float_dtypes]
 
  @_cached_property
  def floating(self):

jax/numpy/__init__.py

@@ -273,6 +273,15 @@
 except ImportError:
  pass
 
+# TODO: Remove the try-except once we upgrade to ml_dtypes 0.5.0
+try:
+ from jax._src.numpy.lax_numpy import (
+ float8_e3m4 as float8_e3m4,
+ float8_e4m3 as float8_e4m3,
+ )
+except ImportError:
+ pass
+
 from jax._src.numpy.array_api_metadata import (
  __array_api_version__ as __array_api_version__,
  __array_namespace_info__ as __array_namespace_info__,

tests/dtypes_test.py

@@ -64,6 +64,10 @@
 fp8_dtypes = [np.dtype(dtypes.float8_e4m3b11fnuz), np.dtype(dtypes.float8_e4m3fn),
  np.dtype(dtypes.float8_e4m3fnuz), np.dtype(dtypes.float8_e5m2),
  np.dtype(dtypes.float8_e5m2fnuz)]
+if dtypes.float8_e3m4 is not None:
+ fp8_dtypes += [np.dtype(dtypes.float8_e3m4)]
+if dtypes.float8_e4m3 is not None:
+ fp8_dtypes += [np.dtype(dtypes.float8_e4m3)]
 float_dtypes += fp8_dtypes
 custom_float_dtypes += fp8_dtypes