[project @ 2002-12-11 15:36:20 by simonmar]
Merge the eval-apply-branch on to the HEAD ------------------------------------------ This is a change to GHC's evaluation model in order to ultimately make GHC more portable and to reduce complexity in some areas. At some point we'll update the commentary to describe the new state of the RTS. Pending that, the highlights of this change are: - No more Su. The Su register is gone, update frames are one word smaller. - Slow-entry points and arg checks are gone. Unknown function calls are handled by automatically-generated RTS entry points (AutoApply.hc, generated by the program in utils/genapply). - The stack layout is stricter: there are no "pending arguments" on the stack any more, the stack is always strictly a sequence of stack frames. This means that there's no need for LOOKS_LIKE_GHC_INFO() or LOOKS_LIKE_STATIC_CLOSURE() any more, and GHC doesn't need to know how to find the boundary between the text and data segments (BIG WIN!). - A couple of nasty hacks in the mangler caused by the neet to identify closure ptrs vs. info tables have gone away. - Info tables are a bit more complicated. See InfoTables.h for the details. - As a side effect, GHCi can now deal with polymorphic seq. Some bugs in GHCi which affected primitives and unboxed tuples are now fixed. - Binary sizes are reduced by about 7% on x86. Performance is roughly similar, some programs get faster while some get slower. I've seen GHCi perform worse on some examples, but haven't investigated further yet (GHCi performance *should* be about the same or better in theory). - Internally the code generator is rather better organised. I've moved info-table generation from the NCG into the main codeGen where it is shared with the C back-end; info tables are now emitted as arrays of words in both back-ends. The NCG is one step closer to being able to support profiling. This has all been fairly thoroughly tested, but no doubt I've messed up the commit in some way.