Implement foldr/cons/build
There seem to be various issues with general fold/cons
and even cons/build
rules, but it seems pretty clear to me that the simple fold/cons/build
rule is a good idea. It doesn't do much for nofib allocation, but it seems to improve some other analyses and speed several benchmarks up, including speeding up some things that other fusion changes slowed down. I say "seems to" because I never trust my timings much at all.
{-# RULES
"foldr/cons/build" forall c n x (g::forall b. (a->b->b) -> b -> b) .
foldr c n (x:build g) = c x (g c n)
#-}
Trac metadata
Trac field | Value |
---|---|
Version | 7.9 |
Type | Task |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | libraries/base |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | ekmett, hvr |
Operating system | |
Architecture |