Bounded instance for Word (and possibly others) uses explicitly unboxed literals

There's a comment above saying GHC won't optimise. I think since 7.8 they are unboxed by default, so that comment and the explicit constructors can be removed.

Trac metadata

Trac field	Value
Version	7.8.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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changed weight to 5

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changed title from Bounded instance for Word (and possibly others) uses unboxed literals to Bounded instance for Word (and possibly others) uses explicitly unboxed literals

assigned to @trac-ekmett

For reference, from libraries/base/GHC/Enum.hs:

 instance Bounded Word where
     minBound = 0
 
     -- use unboxed literals for maxBound, because GHC doesn't optimise
     -- (fromInteger 0xffffffff :: Word).
 #if WORD_SIZE_IN_BITS == 32
     maxBound = W# (int2Word# 0xFFFFFFFF#)
 #elif WORD_SIZE_IN_BITS == 64
     maxBound = W# (int2Word# 0xFFFFFFFFFFFFFFFF#)
 #else
 #error Unhandled value for WORD_SIZE_IN_BITS
 #endif

Trac metadata

Trac field	Value
Component	Compiler → Core Libraries
CC	→ core-libraries-committee@haskell.org

added core libraries label

That's strange... I tried with GHC's going back to 6.12.3 but couldn't reproduce the problem described. I always end up with GHC.Word.W# (__word 18446744073709551615) with -ddump-simpl.

changed milestone to %⊥

changed weight to 0

Trac metadata

Trac field	Value
Type	Bug → Task
Priority	normal → lowest

added Ttask label and removed Tbug label

1. 12.3 was released in June 2010. That code was introduced in

commit 9eef5c0bc0cf1670f55427dacf592c0ea415e7e6
Author: simonmar <unknown>
Date:   Tue May 25 09:27:16 2004 +0000

    [project @ 2004-05-25 09:27:16 by simonmar]
    Small performance hack in maxBound::Word.

In libraries/base/GHC/Base.hs:

maxInt, minInt :: Int           
 
{- Seems clumsy. Should perhaps put minInt and MaxInt directly into MachDeps.h -}
#if WORD_SIZE_IN_BITS == 31     
minInt  = I# (-0x40000000#)     
maxInt  = I# 0x3FFFFFFF#        
#elif WORD_SIZE_IN_BITS == 32   
minInt  = I# (-0x80000000#)     
maxInt  = I# 0x7FFFFFFF#        
#else
minInt  = I# (-0x8000000000000000#)
maxInt  = I# 0x7FFFFFFFFFFFFFFF#
#endif

mentioned in commit 75a8349b

added Tbug label

added Plow label