[commit: ghc] master: Support large SLIDE instructions. (6dc22bf)

[Paolo Capriotti]

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

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/6dc22bfa9d0026c09abf94e44f04fb9e761d4e54

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

commit 6dc22bfa9d0026c09abf94e44f04fb9e761d4e54
Author: Paolo Capriotti <p.capriotti at gmail.com>
Date:   Thu Apr 5 09:52:18 2012 +0100

    Support large SLIDE instructions.
    
    The bytecode generator used to keep track of the stack depth with a
    16-bit counter, which could overflow for very large BCOs, resulting in
    incorrect bytecode.
    
    This commit switches to a word-sized counter, and eagerly panics
    whenever an operand is too big, instead of truncating the result.
    
    This allows us to work around the 16-bit limitation in the case of SLIDE
    instructions, since we can simply factor it into multiple SLIDEs with
    smaller arguments.

 compiler/ghci/ByteCodeGen.lhs |  110 ++++++++++++++++++++++++----------------
 1 files changed, 66 insertions(+), 44 deletions(-)


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

    git show 6dc22bfa9d0026c09abf94e44f04fb9e761d4e54