ccl-execute is a built-in function in `C source code'.

(ccl-execute CCL-PROG REG)

Execute CCL-PROGRAM with registers initialized by REGISTERS.

CCL-PROGRAM is a CCL program name (symbol)
or compiled code generated by `ccl-compile' (for backward compatibility.
In the latter case, the execution overhead is bigger than in the former).
No I/O commands should appear in CCL-PROGRAM.

REGISTERS is a vector of [R0 R1 ... R7] where RN is an initial value
for the Nth register.

As side effect, each element of REGISTERS holds the value of
the corresponding register after the execution.

See the documentation of `define-ccl-program' for a definition of CCL