The name is misleading. The document omits the part about executing top level forms. It does mention compiling them, though:
"[...] Compile the current toplevel form.
With (positive) prefix argument the form is compiled with maximal
debug settings (‘C-u’). With negative prefix argument it is compiled for
speed (‘M--’). If a numeric argument is passed set debug or speed settings
to it depending on its sign."
Comments
Even the documentation is wrong. For C-c C-c
The name slime-compile-defun indicates that it compiles DEFUN forms.
It actually compiles AND executes top-level forms.
The name is misleading. The document omits the part about executing top level forms. It does mention compiling them, though:
"[...] Compile the current toplevel form.
With (positive) prefix argument the form is compiled with maximal debug settings (‘C-u’). With negative prefix argument it is compiled for speed (‘M--’). If a numeric argument is passed set debug or speed settings to it depending on its sign."