[Haskell-cafe] CPU with Haskell support

[Henning Thielemann]

Hi all,

every now and then I think it would be cool to have a microprocessor that 
supports Haskell in a way. A processor where lazy evaluation is not 
overhead but an optimization opportunity, a processor that can make use of 
the explicit data dependencies in Haskell programs in order to utilize 
many computation units in parallel. I know of the Reduceron project, which 
evolves only slowly and if it somewhen is ready for use it is uncertain 
whether it can compete with stock CPUs since FPGA's need much more chip 
space for the same logic.

I got to know that in todays x86 processors you can alter the instruction 
set, which is mainly used for bugfixes. Wouldn't it be interesting to add 
some instructions for Haskell support? However, I suspect that such a 
patch might be rendered invalid by new processor generations with changed 
internal details. Fortunately, there are processors that are designed for 
custom instruction set extensions:
    https://en.wikipedia.org/wiki/Xtensa

Would it be sensible to create a processor based on such a design? I have 
no idea what it might cost, and you would still need some peripheral 
circuitry to run it. What could processor instructions for Haskell support 
look like? Has anyone already thought in this direction?