Refactor f8_t, add bf8_t (#792)

* Refactor f8_t to add bf8_t

* Add check_err impl for f8_t

* Update fp8 test

* Format

* Revert the fix

* Update vector_type implementation

* Add bf8 test

* Add bf8, use BitInt types

* Add bf8 conversion methods

* Update type_convert for fp8/bf8

* Add check_err fp8/bf8 support

* Add subnorm fp8 tests

* Add subnorm bf8 tests

* Fix conversion

* Add bf8 cmake bindings

* Add macros to enable build with disabled fp8/bf8

* Remove is_native method

* Update flag combination for mixed precision instances

* Add more flag checks

* Add another flag to a client example

* Add type traits, decouple f8/bf8 casting

* Clean up

* Decouple fp8 and bf8 flags

* Remove more redundant flags

* Remove leftover comments

include/ck/tensor_operation/gpu/element/unary_element_wise_operation.hpp

@@ -89,6 +89,7 @@ struct PassThrough
     }
 #endif
 
+#if defined CK_ENABLE_FP8
     template <>
     __host__ __device__ void operator()<f8_t, f8_t>(f8_t& y, const f8_t& x) const
     {
@@ -118,6 +119,7 @@ struct PassThrough
     {
         y = type_convert<f8_t>(x);
     }
+#endif
 };
 
 struct UnaryConvert
@@ -146,6 +148,7 @@ struct ConvertBF16RTN
     }
 };
 
+#if defined CK_ENABLE_FP8
 struct ConvertF8SR
 {
     // convert to fp8 using stochastic rounding (SR)
@@ -162,6 +165,7 @@ struct ConvertF8SR
         y = f8_convert_sr<Y>(x);
     }
 };
+#endif
 
 struct Scale
 {