1. 14 May, 2003 4 commits
    • simonmar's avatar
      [project @ 2003-05-14 09:13:52 by simonmar] · 7a236a56
      simonmar authored
      Change the way SRTs are represented:
      Previously, the SRT associated with a function or thunk would be a
      sub-list of the enclosing top-level function's SRT.  But this approach
      can lead to lots of duplication: if a CAF is referenced in several
      different thunks, then it may appear several times in the SRT.
      Let-no-escapes compound the problem, because the occurrence of a
      let-no-escape-bound variable would expand to all the CAFs referred to
      by the let-no-escape.
      The new way is to describe the SRT associated with a function or thunk
      as a (pointer+offset,bitmap) pair, where the pointer+offset points
      into some SRT table (the enclosing function's SRT), and the bitmap
      indicates which entries in this table are "live" for this closure.
      The bitmap is stored in the 16 bits previously used for the length
      field, but this rarely overflows.  When it does overflow, we store the
      bitmap externally in a new "SRT descriptor".
      Now the enclosing SRT can be a set, hence eliminating the duplicates.
      Also, we now have one SRT per top-level function in a recursive group,
      where previously we used to have one SRT for the whole group.  This
      helps keep the size of SRTs down.
      Bottom line: very little difference most of the time.  GHC itself got
      slightly smaller.  One bad case of a module in GHC which had a huge
      SRT has gone away.
      While I was in the area:
        - Several parts of the back-end require bitmaps.  Functions for
          creating bitmaps are now centralised in the Bitmap module.
        - We were trying to be independent of word-size in a couple of
          places in the back end, but we've now abandoned that strategy so I
          simplified things a bit.
    • simonmar's avatar
      [project @ 2003-05-14 09:11:49 by simonmar] · efbac413
      simonmar authored
      Comments only
    • simonmar's avatar
      [project @ 2003-05-14 09:11:06 by simonmar] · c7268677
      simonmar authored
      Calling mmap() with a size > 3Gig results in EINVAL on Linux.  Catch
      this case and report it as an out of memory condition instead of a
    • simonmar's avatar
      [project @ 2003-05-14 09:07:28 by simonmar] · 1d0504a9
      simonmar authored
      Comment only
  2. 13 May, 2003 2 commits
  3. 12 May, 2003 2 commits
  4. 07 May, 2003 4 commits
  5. 06 May, 2003 7 commits
  6. 04 May, 2003 1 commit
  7. 01 May, 2003 3 commits
  8. 29 Apr, 2003 2 commits
  9. 28 Apr, 2003 3 commits
  10. 27 Apr, 2003 2 commits
  11. 25 Apr, 2003 2 commits
  12. 23 Apr, 2003 2 commits
  13. 22 Apr, 2003 4 commits
    • igloo's avatar
      [project @ 2003-04-22 20:39:59 by igloo] · c21fbf92
      igloo authored
      Order declarations in reifications in order of source line number.
      The bugs still there but it bites less often now...
      Also remove the type parameterisation and do some type renaming as
      discussed on the template-haskell list.
    • simonmar's avatar
      [project @ 2003-04-22 16:25:08 by simonmar] · 1da232fc
      simonmar authored
      Fix an obscure bug: the most general kind of heap check,
      HEAP_CHECK_GEN(), is supposed to save the contents of *every* register
      known to the STG machine (used in cases where we either can't figure
      out which ones are live, or doing so would be too much hassle).  The
      problem is that it wasn't saving the L1 register.
      A slight complication arose in that saving the L1 register pushed the
      size of the frame over the 16 words allowed for the size of the bitmap
      stored in the frame, so I changed the layout of the frame a bit.
      Describing all the registers using a single bitmap is overkill when
      only 8 of them can actually be pointers, so now the bitmap is only 8
      bits long and we always skip over a fixed number of non-ptr words to
      account for all the non-ptr regs.  This is all described in StgMacros.h.
    • simonpj's avatar
      [project @ 2003-04-22 11:44:17 by simonpj] · 3c85beaf
      simonpj authored
      Fix the context for derived Typeable instances
    • simonpj's avatar
      [project @ 2003-04-22 09:30:52 by simonpj] · fcda69ed
      simonpj authored
      Stage-2 wibbles to the Expected type changes
  14. 21 Apr, 2003 1 commit
  15. 18 Apr, 2003 1 commit