Investigate performance of CoreTidy
Considering the following profile output (compiling https://ghc.haskell.org/trac/ghc/attachment/ticket/14683/Grammar.hs):
Thu Jan 25 13:11 2018 Time and Allocation Profiling Report (Final)
ghc-stage2 +RTS -p -RTS -B/home/tobias/well-typed/devel/ghc/inplace/lib Grammar.hs -ddump-stg -ddump-simpl -ddump-to-file -fforce-recomp
total time = 20.99 secs (20989 ticks @ 1000 us, 1 processor)
total alloc = 29,250,375,256 bytes (excludes profiling overheads)
COST CENTRE MODULE SRC %time %alloc
CoreTidy HscMain compiler/main/HscMain.hs:1253:27-67 24.2 28.5
Stg2Stg HscMain compiler/main/HscMain.hs:1489:12-44 20.3 24.2
simplCast Simplify compiler/simplCore/Simplify.hs:871:62-87 18.7 15.9
tc_rn_src_decls TcRnDriver compiler/typecheck/TcRnDriver.hs:(494,4)-(556,7) 9.0 6.9
addCoerce-pushCoTyArg Simplify compiler/simplCore/Simplify.hs:(1236,12)-(1237,72) 7.4 6.4
subst_ty TyCoRep compiler/types/TyCoRep.hs:2237:28-32 4.3 5.1
zonkTopDecls TcRnDriver compiler/typecheck/TcRnDriver.hs:(445,16)-(446,43) 1.4 1.1
coercionKind Coercion compiler/types/Coercion.hs:1725:3-7 1.3 3.0
simplExprF1-Lam Simplify compiler/simplCore/Simplify.hs:896:5-39 1.0 1.1- ..the amount of time spent in
CoreTidyis striking, and should be investigated.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 8.2.2 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |