[[ext:c]]
=== ext:c[] Extension for Compressed Instructions

This section describes the ext:c[] extension, which incorporates the
compressed instruction-set extensions designed for application-
and server-class processors.
The ext:c[] extension substantially improves code density across a wide
range of applications, thereby improving performance, area-efficiency,
and energy-efficiency of processors with instruction caches.
It excludes features that improve code density at the cost of performance.

The ext:c[] extension depends upon the extlink:zca[] extension.

If XLEN=32 and the ext:f[] extension is present, the ext:c[] extension additionally
depends upon the extlink:zcf[] extension.

If the ext:d[] extension is present, the ext:c[] extension additionally depends
upon the extlink:zcd[] extension.