Composable Kernel precision support

This topic lists the data type support for the Composable Kernel library on AMD GPUs.

This page lists the data types supported by the library itself and does not indicate hardware support. A type listed here is only usable if the GPU architecture also supports it; otherwise it is unsupported. For data type support across the other ROCm libraries and by GPU architecture, see the Data types and precision support page.

Supported data types overview

The following table summarizes the input and output data types supported by Composable Kernel.

Icon	Definition
✅	Fully supported as both an input and output type.
⚠️	Partially supported as an input or output type.

Data types not listed in the table below are not supported.

Data type	Support
int8	✅
int32	✅
float4 (E2M1)	✅
float6 (E2M3)	✅
float6 (E3M2)	✅
float8 (E4M3)	✅
float8 (E5M2)	✅
float16	✅
bfloat16	✅
float32	✅
float64	✅

Related references

For details about the underlying C++ types used by Composable Kernel, see the following pages:

• Supported scalar data types — the C++ scalar types, their bit widths, and bit-layout descriptions.

• Custom types — the custom types Composable Kernel defines for specialized operations.