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| author | Sebastian Graf <sebastian.graf@kit.edu> | 2021-07-21 15:47:06 +0200 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2021-09-18 12:01:44 -0400 |
| commit | 2c28919f9c79a65d65a2e863a9bd7d0785b5f854 (patch) | |
| tree | e1215af0bfcd84c4c6b5cf2db53a85b4401de07d | |
| parent | 4d245e548d4136a2034d4ec6171268eac2442fb8 (diff) | |
| download | haskell-2c28919f9c79a65d65a2e863a9bd7d0785b5f854.tar.gz | |
CoreUtils: Make exprIsHNF return True for unlifted variables (#20140)
Clearly, evaluating an unlifted variable will never perform any work.
Fixes #20140.
| -rw-r--r-- | compiler/GHC/Core/Utils.hs | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/compiler/GHC/Core/Utils.hs b/compiler/GHC/Core/Utils.hs index b2af755e78..03d3fca294 100644 --- a/compiler/GHC/Core/Utils.hs +++ b/compiler/GHC/Core/Utils.hs @@ -1944,6 +1944,8 @@ exprIsHNFlike is_con is_con_unf = is_hnf_like -- We don't look through loop breakers here, which is a bit conservative -- but otherwise I worry that if an Id's unfolding is just itself, -- we could get an infinite loop + || isUnliftedType (idType v) + -- Unlifted binders are always evaluated (#20140) is_hnf_like (Lit l) = not (isLitRubbish l) -- Regarding a LitRubbish as ConLike leads to unproductive inlining in |