Alain Frisch wrote:

>Brian Hurt wrote:
>  
>
>>where the function is only called from one place, or 3) where inlining
>>opened up signifigant other optimization opportunities.  The classic
>>example for Ocaml here is replacing a call to Pervasives.compare with an
>>integer compare.  Most of the rest of the time, inlining is either a
>>break even proposition, or often a loss.
>>    
>>
>
>Another good situation is when inlining allows the compiler to turn a
>function call to an unknown location into a direct function call (or no
>function call at all). This happens as soon as you write "List.map (fun
>x -> ...)". Inlining List.map would avoid the allocation of the closure
>and a computed call (and then the local abstraction will also be inlined
>in the body of the inlined List.map because it is used only once).
>Currently, OCaml never inlines recursive functions.
>
>  
>

This qualifies as an optimization opportunity- turning a call to 
caml_apply into a direct function call is an optimization.  Which may 
open up other optimization possibilities.  But that was my point- if the 
only thing you're getting out of inlining a function is skipping a 
function call (to a known location), then inlining generally isn't worth 
it- it's only worth it if it opens up other possibilities.

Brian