INLINABLE pragma and newtypes prevents inlining
Compile the following code with 'ghc -O2 -ddump-simpl':
module A where
newtype Size = Size Int
{-# INLINABLE val2 #-}
val2 = Size 0
f n = case val2 of Size s -> s + s > nWith ghc-7.1.20110629, we get the following Core:
A.f1 =
case A.val2 `cast` (A.NTCo:Size :: A.Size ~ GHC.Types.Int)
of _ { GHC.Types.I# x_aoz ->
GHC.Types.I# (GHC.Prim.+# x_aoz x_aoz)
}
A.f = \ (n_ab1 :: GHC.Types.Int) -> GHC.Classes.gtInt A.f1 n_ab1and we get something similar with ghc-7.0.3. In particular, for both versions of ghc, the addition s+s should be simplified to 0, but isn't.
Any of the following changes will let s+s simplify to 0:
- change
newtype Size = ...intodata Size = ... - remove the INLINABLE pragma
- with ghc-7.0.3, turning the INLINABLE pragma into INLINE. However, with ghc-7.1.20110629, the INLINE pragma doesn't fix the problem.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |