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| author | Simon Peyton Jones <simonpj@microsoft.com> | 2012-08-23 16:35:55 +0100 |
|---|---|---|
| committer | Simon Peyton Jones <simonpj@microsoft.com> | 2012-08-23 16:35:55 +0100 |
| commit | 2f08f709cfdace23a4e32d80a57af349f7cc785a (patch) | |
| tree | f31accb43c112f5c06ac8a9c23eb16453f8b40d1 /compiler/specialise | |
| parent | b04ff2fe83d8a5f9c176739559ac722521a7bdcc (diff) | |
| download | haskell-2f08f709cfdace23a4e32d80a57af349f7cc785a.tar.gz | |
Don't specialise on implicit-parameter arguments in Specalise
This is a fix for Trac #7101
Diffstat (limited to 'compiler/specialise')
| -rw-r--r-- | compiler/specialise/Specialise.lhs | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/compiler/specialise/Specialise.lhs b/compiler/specialise/Specialise.lhs index 6892c9c6ad..4307ff75df 100644 --- a/compiler/specialise/Specialise.lhs +++ b/compiler/specialise/Specialise.lhs @@ -1573,10 +1573,7 @@ mkCallUDs :: Id -> [CoreExpr] -> UsageDetails mkCallUDs f args | not (want_calls_for f) -- Imported from elsewhere || null theta -- Not overloaded - || not (all isClassPred theta) - -- Only specialise if all overloading is on class params. - -- In ptic, with implicit params, the type args - -- *don't* say what the value of the implicit param is! + || not (all type_determines_value theta) || not (spec_tys `lengthIs` n_tyvars) || not ( dicts `lengthIs` n_dicts) || not (any interestingDict dicts) -- Note [Interesting dictionary arguments] @@ -1603,6 +1600,13 @@ mkCallUDs f args | otherwise = Nothing want_calls_for f = isLocalId f || isInlinablePragma (idInlinePragma f) + + type_determines_value pred = isClassPred pred && not (isIPPred pred) + -- Only specialise if all overloading is on non-IP *class* params, + -- because these are the ones whose *type* determines their *value*. + -- In ptic, with implicit params, the type args + -- *don't* say what the value of the implicit param is! + -- See Trac #7101 \end{code} Note [Interesting dictionary arguments] |