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| author | Simon Peyton Jones <simonpj@microsoft.com> | 2014-03-13 12:11:01 +0000 |
|---|---|---|
| committer | Simon Peyton Jones <simonpj@microsoft.com> | 2014-03-13 12:11:01 +0000 |
| commit | 518706bf6ec91ece77f2195cbb1361ebbc1972f0 (patch) | |
| tree | 6589487c0c45e2e4f2136e91a5536af6775ff924 /libraries/base/Data/Bits.hs | |
| parent | 0d66095d5080f190d18d6d5f8b85ac7138236cb0 (diff) | |
| download | haskell-518706bf6ec91ece77f2195cbb1361ebbc1972f0.tar.gz | |
Add shiftR and shiftL implementations to instance Bits Integer
Apart from simply making sense (avoid the conditional in 'shift'),
this makes left and right shifts on Integer more likely to inline
(plain 'shift' is just too large); and this in turn is important
when fixing the Integer case of #8832
Diffstat (limited to 'libraries/base/Data/Bits.hs')
| -rw-r--r-- | libraries/base/Data/Bits.hs | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/libraries/base/Data/Bits.hs b/libraries/base/Data/Bits.hs index 28cd0241db..81b180bb7e 100644 --- a/libraries/base/Data/Bits.hs +++ b/libraries/base/Data/Bits.hs @@ -437,6 +437,9 @@ instance Bits Integer where complement = complementInteger shift x i@(I# i#) | i >= 0 = shiftLInteger x i# | otherwise = shiftRInteger x (negateInt# i#) + shiftL x (I# i#) = shiftLInteger x i# + shiftR x (I# i#) = shiftRInteger x i# + testBit x (I# i) = testBitInteger x i zeroBits = 0 |