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* [project @ 2000-03-30 10:37:09 by simonmar]simonmar2000-03-301-101/+0
| | | | | Remove this file, it moved to ghc/rts. (sigh, I thought I removed it already, but apparently not).
* [project @ 2000-03-23 17:45:17 by simonpj]simonpj2000-03-231-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This utterly gigantic commit is what I've been up to in background mode in the last couple of months. Originally the main goal was to get rid of Con (staturated constant applications) in the CoreExpr type, but one thing led to another, and I kept postponing actually committing. Sorry. Simon, 23 March 2000 I've tested it pretty thoroughly, but doubtless things will break. Here are the highlights * Con is gone; the CoreExpr type is simpler * NoRepLits have gone * Better usage info in interface files => less recompilation * Result type signatures work * CCall primop is tidied up * Constant folding now done by Rules * Lots of hackery in the simplifier * Improvements in CPR and strictness analysis Many bug fixes including * Sergey's DoCon compiles OK; no loop in the strictness analyser * Volker Wysk's programs don't crash the CPR analyser I have not done much on measuring compilation times and binary sizes; they could have got worse. I think performance has got significantly better, though, in most cases. Removing the Con form of Core expressions ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The big thing is that For every constructor C there are now *two* Ids: C is the constructor's *wrapper*. It evaluates and unboxes arguments before calling $wC. It has a perfectly ordinary top-level defn in the module defining the data type. $wC is the constructor's *worker*. It is like a primop that simply allocates and builds the constructor value. Its arguments are the actual representation arguments of the constructor. Its type may be different to C, because: - useless dict args are dropped - strict args may be flattened For every primop P there is *one* Id, its (curried) Id Neither contructor worker Id nor the primop Id have a defminition anywhere. Instead they are saturated during the core-to-STG pass, and the code generator generates code for them directly. The STG language still has saturated primops and constructor applications. * The Const type disappears, along with Const.lhs. The literal part of Const.lhs reappears as Literal.lhs. Much tidying up in here, to bring all the range checking into this one module. * I got rid of NoRep literals entirely. They just seem to be too much trouble. * Because Con's don't exist any more, the funny C { args } syntax disappears from inteface files. Parsing ~~~~~~~ * Result type signatures now work f :: Int -> Int = \x -> x -- The Int->Int is the type of f g x y :: Int = x+y -- The Int is the type of the result of (g x y) Recompilation checking and make ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * The .hi file for a modules is not touched if it doesn't change. (It used to be touched regardless, forcing a chain of recompilations.) The penalty for this is that we record exported things just as if they were mentioned in the body of the module. And the penalty for that is that we may recompile a module when the only things that have changed are the things it is passing on without using. But it seems like a good trade. * -recomp is on by default Foreign declarations ~~~~~~~~~~~~~~~~~~~~ * If you say foreign export zoo :: Int -> IO Int then you get a C produre called 'zoo', not 'zzoo' as before. I've also added a check that complains if you export (or import) a C procedure whose name isn't legal C. Code generation and labels ~~~~~~~~~~~~~~~~~~~~~~~~~~ * Now that constructor workers and wrappers have distinct names, there's no need to have a Foo_static_closure and a Foo_closure for constructor Foo. I nuked the entire StaticClosure story. This has effects in some of the RTS headers (i.e. s/static_closure/closure/g) Rules, constant folding ~~~~~~~~~~~~~~~~~~~~~~~ * Constant folding becomes just another rewrite rule, attached to the Id for the PrimOp. To achieve this, there's a new form of Rule, a BuiltinRule (see CoreSyn.lhs). The prelude rules are in prelude/PrelRules.lhs, while simplCore/ConFold.lhs has gone. * Appending of constant strings now works, using fold/build fusion, plus the rewrite rule unpack "foo" c (unpack "baz" c n) = unpack "foobaz" c n Implemented in PrelRules.lhs * The CCall primop is tidied up quite a bit. There is now a data type CCall, defined in PrimOp, that packages up the info needed for a particular CCall. There is a new Id for each new ccall, with an big "occurrence name" {__ccall "foo" gc Int# -> Int#} In interface files, this is parsed as a single Id, which is what it is, really. Miscellaneous ~~~~~~~~~~~~~ * There were numerous places where the host compiler's minInt/maxInt was being used as the target machine's minInt/maxInt. I nuked all of these; everything is localised to inIntRange and inWordRange, in Literal.lhs * Desugaring record updates was broken: it didn't generate correct matches when used withe records with fancy unboxing etc. It now uses matchWrapper. * Significant tidying up in codeGen/SMRep.lhs * Add __word, __word64, __int64 terminals to signal the obvious types in interface files. Add the ability to print word values in hex into C code. * PrimOp.lhs is no longer part of a loop. Remove PrimOp.hi-boot* Types ~~~~~ * isProductTyCon no longer returns False for recursive products, nor for unboxed products; you have to test for these separately. There's no reason not to do CPR for recursive product types, for example. Ditto splitProductType_maybe. Simplification ~~~~~~~~~~~~~~~ * New -fno-case-of-case flag for the simplifier. We use this in the first run of the simplifier, where it helps to stop messing up expressions that the (subsequent) full laziness pass would otherwise find float out. It's much more effective than previous half-baked hacks in inlining. Actually, it turned out that there were three places in Simplify.lhs that needed to know use this flag. * Make the float-in pass push duplicatable bindings into the branches of a case expression, in the hope that we never have to allocate them. (see FloatIn.sepBindsByDropPoint) * Arrange that top-level bottoming Ids get a NOINLINE pragma This reduced gratuitous inlining of error messages. But arrange that such things still get w/w'd. * Arrange that a strict argument position is regarded as an 'interesting' context, so that if we see foldr k z (g x) then we'll be inclined to inline g; this can expose a build. * There was a missing case in CoreUtils.exprEtaExpandArity that meant we were missing some obvious cases for eta expansion Also improve the code when handling applications. * Make record selectors (identifiable by their IdFlavour) into "cheap" operations. [The change is a 2-liner in CoreUtils.exprIsCheap] This means that record selection may be inlined into function bodies, which greatly improves the arities of overloaded functions. * Make a cleaner job of inlining "lone variables". There was some distributed cunning, but I've centralised it all now in SimplUtils.analyseCont, which analyses the context of a call to decide whether it is "interesting". * Don't specialise very small functions in Specialise.specDefn It's better to inline it. Rather like the worker/wrapper case. * Be just a little more aggressive when floating out of let rhss. See comments with Simplify.wantToExpose A small change with an occasional big effect. * Make the inline-size computation think that case x of I# x -> ... is *free*. CPR analysis ~~~~~~~~~~~~ * Fix what was essentially a bug in CPR analysis. Consider letrec f x = let g y = let ... in f e1 in if ... then (a,b) else g x g has the CPR property if f does; so when generating the final annotated RHS for f, we must use an envt in which f is bound to its final abstract value. This wasn't happening. Instead, f was given the CPR tag but g wasn't; but of course the w/w pass gives rotten results in that case!! (Because f's CPR-ness relied on g's.) On they way I tidied up the code in CprAnalyse. It's quite a bit shorter. The fact that some data constructors return a constructed product shows up in their CPR info (MkId.mkDataConId) not in CprAnalyse.lhs Strictness analysis and worker/wrapper ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * BIG THING: pass in the demand to StrictAnal.saExpr. This affects situations like f (let x = e1 in (x,x)) where f turns out to have strictness u(SS), say. In this case we can mark x as demanded, and use a case expression for it. The situation before is that we didn't "know" that there is the u(SS) demand on the argument, so we simply computed that the body of the let expression is lazy in x, and marked x as lazily-demanded. Then even after f was w/w'd we got let x = e1 in case (x,x) of (a,b) -> $wf a b and hence let x = e1 in $wf a b I found a much more complicated situation in spectral/sphere/Main.shade, which improved quite a bit with this change. * Moved the StrictnessInfo type from IdInfo to Demand. It's the logical place for it, and helps avoid module loops * Do worker/wrapper for coerces even if the arity is zero. Thus: stdout = coerce Handle (..blurg..) ==> wibble = (...blurg...) stdout = coerce Handle wibble This is good because I found places where we were saying case coerce t stdout of { MVar a -> ... case coerce t stdout of { MVar b -> ... and the redundant case wasn't getting eliminated because of the coerce.
* [project @ 1999-12-20 10:34:27 by simonpj]simonpj1999-12-201-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit implements a substantial re-organisation of the Prelude It also fixes a couple of small renamer bugs that were reported recently (notably, Sven pointed out that we weren't reporting unused imports properly) My original goal was to get rid of all "orphan" modules (i.e. ones with instance decls that don't belong either to a tycon or a class defined in the same module). This should reduce the number of interface files that have to be read when compiling small Haskell modules. But like most expeditions into the Prelude Swamp, it spiraled out of control. The result is quite satisfactory, though. GONE AWAY: PrelCCall, PrelNumExtra NEW: PrelReal, PrelFloat, PrelByteArr, PrelNum.hi-boot (The extra PrelNum.hi-boot is because of a tiresome thin-air Id, addr2Integer, which used to be in PrelBase.) Quite a lot of types have moved from one module to another, which entails some changes to part of the compiler (PrelInfo, PrelMods) etc, and there are a few places in the RTS includes and even in the driver that know about these home modules (alas). So the rough structure is as follows, in (linearised) dependency order [this list now appears in PrelBase.lhs] PrelGHC Has no implementation. It defines built-in things, and by importing it you bring them into scope. The source file is PrelGHC.hi-boot, which is just copied to make PrelGHC.hi Classes: CCallable, CReturnable PrelBase Classes: Eq, Ord, Functor, Monad Types: list, (), Int, Bool, Ordering, Char, String PrelTup Types: tuples, plus instances for PrelBase classes PrelShow Class: Show, plus instances for PrelBase/PrelTup types PrelEnum Class: Enum, plus instances for PrelBase/PrelTup types PrelMaybe Type: Maybe, plus instances for PrelBase classes PrelNum Class: Num, plus instances for Int Type: Integer, plus instances for all classes so far (Eq, Ord, Num, Show) Integer is needed here because it is mentioned in the signature of 'fromInteger' in class Num PrelReal Classes: Real, Integral, Fractional, RealFrac plus instances for Int, Integer Types: Ratio, Rational plus intances for classes so far Rational is needed here because it is mentioned in the signature of 'toRational' in class Real Ix Classes: Ix, plus instances for Int, Bool, Char, Integer, Ordering, tuples PrelArr Types: Array, MutableArray, MutableVar Does *not* contain any ByteArray stuff (see PrelByteArr) Arrays are used by a function in PrelFloat PrelFloat Classes: Floating, RealFloat Types: Float, Double, plus instances of all classes so far This module contains everything to do with floating point. It is a big module (900 lines) With a bit of luck, many modules can be compiled without ever reading PrelFloat.hi PrelByteArr Types: ByteArray, MutableByteArray We want this one to be after PrelFloat, because it defines arrays of unboxed floats. Other Prelude modules are much easier with fewer complex dependencies.
* [project @ 1999-07-14 11:15:09 by simonmar]simonmar1999-07-141-1/+3
| | | | add NonTermination_closure.
* [project @ 1999-05-04 08:52:22 by sof]sof1999-05-041-2/+2
| | | | Moved DLL-related macros out of Stg.h and into separate .h file
* [project @ 1999-03-17 13:19:19 by simonm]simonm1999-03-171-23/+27
| | | | | | | | | | | | | - Stack overflow now generates an (AsyncException StackOverflow) exception, which can be caught as normal. - Add a stack overflow handler to the top-level mainIO handler, with the standard behaviour (i.e. call the stack overflow hook and then exit). - Add a test for stack overflow catching. - Fix a couple of bugs in async exception support.
* [project @ 1999-03-02 19:44:07 by sof]sof1999-03-021-22/+26
| | | | | - misc changes to support DLLs - StgNat* --> StgWord*
* [project @ 1999-02-05 16:02:18 by simonm]simonm1999-02-051-1/+3
| | | | Copyright police.
* [project @ 1999-01-27 14:51:14 by simonpj]simonpj1999-01-271-47/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Finally! This commits the ongoing saga of Simon's hygiene sweep FUNCTIONALITY ~~~~~~~~~~~~~ a) The 'unused variable' warnings from the renamer work. b) Better error messages here and there, esp type checker c) Fixities for Haskell 98 (maybe I'd done that before) d) Lazy reporting of name clashes for Haskell 98 (ditto) HYGIENE ~~~~~~~ a) type OccName has its own module. OccNames are represented by a single FastString, not three as in the last round. This string is held in Z-encoded form; a decoding function decodes for printing in user error messages. There's a nice tight encoding for (,,,,,,,,,,,,,,,,,,,,,,,,,,,,,) b) type Module is a proper ADT, in module OccName c) type RdrName is a proper ADT, in its own module d) type Name has a new, somwhat tidier, representation e) much grunting in the renamer to get Provenances right. This makes error messages look better (no spurious qualifiers)
* [project @ 1999-01-26 11:12:41 by simonm]simonm1999-01-261-5/+5
| | | | | | | | - Add Stable Names - Stable pointers and stable names are now both provided by the "Stable" module in ghc/lib/exts. Documentation is updated, and Foriegn still exports the stable pointer operations for backwards compatibility.
* [project @ 1998-12-02 13:17:09 by simonm]simonm1998-12-021-0/+88
Move 4.01 onto the main trunk.