Changes between Version 7 and Version 8 of Commentary/Rts/HaskellExecution/PointerTagging


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Timestamp:
Dec 10, 2009 1:21:27 PM (4 years ago)
Author:
simonmar
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  • Commentary/Rts/HaskellExecution/PointerTagging

    v7 v8  
    55Paper: [http://www.haskell.org/~simonmar/papers/ptr-tagging.pdf Faster laziness using dynamic pointer tagging] 
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    7 In GHC we "tag" pointers to heap objects with information about the object they point to.  The tag goes in the low 2 bits of the pointer, which would normally be zero since heap objects are always [wiki:Commentary/Rts/Word word]-aligned (3 bits on a 64-bit platform). 
     7In GHC we "tag" pointers to heap objects with information about the object they point to.  The tag goes in the low 2 bits (3 bits on a 64-bit platform) of the pointer, which would normally be zero since heap objects are always [wiki:Commentary/Rts/Word word]-aligned. 
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    99The way the tag bits are used depends on the type of object pointed to: