Change `-fprof-late` to insert cost centres after unfolding creation.wip/andreask/late_cc

The former behaviour of adding cost centres after optimization but
before unfoldings are created is not available via the flag
`prof-late-inline` instead.

I also reduced the overhead of -fprof-late* by pushing the cost centres
into lambdas. This means the cost centres will only account for
execution of functions and not their partial application.

Further I made LATE_CC cost centres it's own CC flavour so they now
won't clash with user defined ones if a user uses the same string for
a custom scc.

LateCC: Don't put cost centres inside constructor workers.

With -fprof-late they are rarely useful as the worker is usually
inlined. Even if the worker is not inlined or we use -fprof-late-linline
they are generally not helpful but bloat compile and run time
significantly. So we just don't add sccs inside constructor workers.

-------------------------
Metric Decrease:
    T13701
-------------------------

1 files changed, 6 insertions, 0 deletions

diff --git a/docs/users_guide/debugging.rst b/docs/users_guide/debugging.rst
index 0c09c4c3ec..87a689c268 100644
--- a/docs/users_guide/debugging.rst
+++ b/docs/users_guide/debugging.rst
@@ -446,6 +446,12 @@ subexpression elimination pass.
 
     Dump output of Core preparation pass
 
+.. ghc-flag:: -ddump-late-cc
+    :shortdesc: Dump core with late cost centres added
+    :type: dynamic
+
+    Dump output of LateCC pass after cost centres have been added.
+
 .. ghc-flag:: -ddump-view-pattern-commoning
     :shortdesc: Dump commoned view patterns
     :type: dynamic