Historical page

This page is a bunch of notes on the new code generator. It is outdated and is here only for historical reasons.It should probably be removed. See Code Generator page for a description of current code generator.

Cleanup after the new codegen is enabled

The new codegen was enabled by default in 832077ca5393d298324cb6b0a2cb501e27209768. Now that the switch has been made, we can remove all the cruft associated with the old code generator. There are dependencies between some of the components, so we have to do things in the right order. Here is a list of the cleanup tasks, and notes about dependencies:

Independent tasks

• Use BlockId or Label consistently, currently we use a mixture of the two. Maybe get rid of the BlockId module.

• Remove live-var and CAF lists from StgSyn, and then clean up CoreToStg

• Fix the layering: GHC.Cmm.* modules should not depend on GHC.StgToCmm.*

Towards removing OldCmm

• IN PROGRESS (Simon M): Change the NCG over to consume new Cmm. We possibly also want the generated native code to use the Hoopl Block representation, although that will mean changing branch instructions to have both true and false targets, rather than true and fallthrough as we have now.

• Remove cmm/CmmCvt (this will save some compile-time too)

• Remove cmm/OldCmm*, cmm/PprOldCmm etc.

Later

• Do the new SRT story (ToDo: write a wiki page about this)