[project @ 2001-08-17 17:18:51 by apt]
How I spent my summer vacation. Primops ------- The format of the primops.txt.pp file has been enhanced to allow (latex-style) primop descriptions to be included. There is a new flag to genprimopcode that generates documentation including these descriptions. A first cut at descriptions of the more interesting primops has been made, and the file has been reordered a bit. 31-bit words ------------ The front end now can cope with the possibility of 31-bit (or even 30-bit) Int# and Word# types. The only current use of this is to generate external .core files that can be translated into OCAML source files (OCAML uses a one-bit tag to distinguish integers from pointers). The only way to get this right now is by hand-defining the preprocessor symbol WORD_SIZE_IN_BITS, which is normally set automatically from the familiar WORD_SIZE_IN_BYTES. Just in case 31-bit words are used, we now have Int32# and Word32# primitive types and an associated family of operators, paralleling the existing 64-bit stuff. Of course, none of the operators actually need to be implemented in the absence of a 31-bit backend. There has also been some minor re-jigging of the 32 vs. 64 bit stuff. See the description at the top of primops.txt.pp file for more details. Note that, for the first time, the *type* of a primop can now depend on the target word size. Also, the family of primops intToInt8#, intToInt16#, etc. have been renamed narrow8Int#, narrow16Int#, etc., to emphasize that they work on Int#'s and don't actually convert between types. Addresses --------- As another part of coping with the possibility of 31-bit ints, the addr2Int# and int2Addr# primops are now thoroughly deprecated (and not even defined in the 31-bit case) and all uses of them have been removed except from the (deprecated) module hslibs/lang/Addr Addr# should now be treated as a proper abstract type, and has these suitable operators: nullAddr# : Int# -> Addr# (ignores its argument; nullary primops cause problems at various places) plusAddr# : Addr# -> Int# -> Addr# minusAddr : Addr# -> Addr# -> Int# remAddr# : Addr# -> Int# -> Int# Obviously, these don't allow completely arbitrary offsets if 31-bit ints are in use, but they should do for all practical purposes. It is also still possible to generate an address constant, and there is a built-in rule that makes use of this to remove the nullAddr# calls. Misc ---- There is a new compile flag -fno-code that causes GHC to quit after generating .hi files and .core files (if requested) but before generating STG. Z-encoded names for tuples have been rationalized; e.g., Z3H now means an unboxed 3-tuple, rather than an unboxed tuple with 3 commas (i.e., a 4-tuple)! Removed misc. litlits in hslibs/lang Misc. small changes to external core format. The external core description has also been substantially updated, and incorporates the automatically-generated primop documentation; its in the repository at /papers/ext-core/core.tex. A little make-system addition to allow passing CPP options to compiler and library builds.