[commit: ghc] master: Code-size optimisation for top-level indirections (#7308) (7da1376)

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/7da13762664c1bec8e2a1ee5c7106cca3b32a98f

>---------------------------------------------------------------

commit 7da13762664c1bec8e2a1ee5c7106cca3b32a98f
Author: Simon Marlow <[email protected]>
Date:   Tue Oct 9 08:49:25 2012 +0100

    Code-size optimisation for top-level indirections (#7308)
    
    Top-level indirections are often generated when there is a cast, e.g.
    
    foo :: T
    foo = bar `cast` (some coercion)
    
    For these we were generating a full-blown CAF, which is a fair chunk
    of code.
    
    This patch makes these indirections generate a single IND_STATIC
    closure (4 words) instead.  This is exactly what the CAF would
    evaluate to eventually anyway, we're just shortcutting the whole
    process.

 compiler/cmm/CmmInfo.hs           |    3 +-
 compiler/cmm/SMRep.lhs            |   11 +++++++++-
 compiler/codeGen/StgCmm.hs        |   13 ++++++-----
 compiler/codeGen/StgCmmBind.hs    |   40 ++++++++++++++++++++++++++++--------
 compiler/codeGen/StgCmmClosure.hs |    8 +++++++
 compiler/codeGen/StgCmmHeap.hs    |    6 +---
 6 files changed, 60 insertions(+), 21 deletions(-)


Diff suppressed because of size. To see it, use:

    git show 7da13762664c1bec8e2a1ee5c7106cca3b32a98f