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* compiler: de-lhs simplCore/Austin Seipp2014-12-031-316/+0
| | | | Signed-off-by: Austin Seipp <austin@well-typed.com>
* Fix garbled comment wordingSimon Peyton Jones2014-09-191-2/+3
| | | | Thanks to Gabor for pointing this out
* Use mapAccumL (refactoring only)Simon Peyton Jones2014-09-191-8/+1
| | | | Fixes Trac #9529
* Typos in commentsGabor Greif2014-08-291-2/+2
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* Fix a bug in CSE, for INLINE/INLNEABLE thingsSimon Peyton Jones2014-08-291-44/+40
| | | | | | | | | | | | Previusly we simply weren't doing CSE at all on things whose unfolding were not always-active, for reasons explained in Note [CSE for INLINE and NOINLINE]. But that was bad! Making something INLNEABLE meant that its RHS was no longer CSE'd, and that made some nofib programs worse. And it's entirely unnecessary. I thoguht it through again, wrote new comments (under the same Note), and things are better again.
* Add LANGUAGE pragmas to compiler/ source filesHerbert Valerio Riedel2014-05-151-0/+2
| | | | | | | | | | | | | | | | | | In some cases, the layout of the LANGUAGE/OPTIONS_GHC lines has been reorganized, while following the convention, to - place `{-# LANGUAGE #-}` pragmas at the top of the source file, before any `{-# OPTIONS_GHC #-}`-lines. - Moreover, if the list of language extensions fit into a single `{-# LANGUAGE ... -#}`-line (shorter than 80 characters), keep it on one line. Otherwise split into `{-# LANGUAGE ... -#}`-lines for each individual language extension. In both cases, try to keep the enumeration alphabetically ordered. (The latter layout is preferable as it's more diff-friendly) While at it, this also replaces obsolete `{-# OPTIONS ... #-}` pragma occurences by `{-# OPTIONS_GHC ... #-}` pragmas.
* Fix egregious omission in CSE (Trac #5996)Simon Peyton Jones2013-11-121-21/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a bad omission in CSE, thanks to 'michaelt' for spotting it, and correctly identifying the fix (in cseRhs). The trouble was with x1 = C a b x2 = C x1 b y1 = C a b y2 = C y1 b we were not commoning up y2=x2, because we failed to substitute y1:=x1, so y2's RHS looked different to x2's I also refactoring, so taht the cs_map in a CSEnv map is cs_map :: CoreMap (OutExpr, Id) instead of cs_map :: CoreMap (OutExpr, OutExpr) Much nicer! This doesn't make much difference to allocation, but it gives a surprisingly big benefit to binary size. -------------------------------------------------------------------------------- Program Size Allocs Runtime Elapsed TotalMem -------------------------------------------------------------------------------- ansi -1.7% -0.8% 0.00 0.00 +0.0% bspt -1.6% -1.5% 0.01 0.01 +0.0% cacheprof -1.8% -0.2% +1.6% +1.9% +2.7% fft -1.4% -1.3% 0.06 0.06 +11.1% ida -1.4% -1.0% 0.12 0.12 +0.0% rfib -1.4% -0.1% 0.03 0.03 +0.0% scs -1.6% -0.1% +1.5% +1.5% +0.0% spectral-norm -1.3% -0.1% -0.2% -0.2% +0.0% tak -1.4% -0.1% 0.02 0.02 +0.0% veritas -1.4% -0.1% 0.00 0.00 +0.0% -------------------------------------------------------------------------------- Min -2.5% -1.5% -11.8% -11.8% -8.0% Max -1.0% +0.0% +2.7% +2.5% +11.1% Geometric Mean -1.3% -0.1% -2.6% -2.6% +0.0%
* Remove old representation of CSEnv; part of #5996Ian Lynagh2013-06-061-71/+1
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* Whitespace only in compiler/simplCore/CSE.lhsIan Lynagh2013-06-061-130/+121
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* A simple improvement to CSESimon Peyton Jones2013-01-171-4/+11
| | | | | See Note [CSE for case expressions]. I don't think this is a big deal, but it's nice, and it's easy.
* Support code generation for unboxed-tuple function argumentsunboxed-tuple-arguments2Max Bolingbroke2012-05-151-29/+1
| | | | | | | | | | | This is done by a 'unarisation' pre-pass at the STG level which translates away all (live) binders binding something of unboxed tuple type. This has the following knock-on effects: * The subkind hierarchy is vastly simplified (no UbxTupleKind or ArgKind) * Various relaxed type checks in typechecker, 'foreign import prim' etc * All case binders may be live at the Core level
* Use -fwarn-tabs when validatingIan Lynagh2011-11-041-0/+7
| | | | | We only use it for "compiler" sources, i.e. not for libraries. Many modules have a -fno-warn-tabs kludge for now.
* Overhaul of infrastructure for profiling, coverage (HPC) and breakpointsSimon Marlow2011-11-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | User visible changes ==================== Profilng -------- Flags renamed (the old ones are still accepted for now): OLD NEW --------- ------------ -auto-all -fprof-auto -auto -fprof-exported -caf-all -fprof-cafs New flags: -fprof-auto Annotates all bindings (not just top-level ones) with SCCs -fprof-top Annotates just top-level bindings with SCCs -fprof-exported Annotates just exported bindings with SCCs -fprof-no-count-entries Do not maintain entry counts when profiling (can make profiled code go faster; useful with heap profiling where entry counts are not used) Cost-centre stacks have a new semantics, which should in most cases result in more useful and intuitive profiles. If you find this not to be the case, please let me know. This is the area where I have been experimenting most, and the current solution is probably not the final version, however it does address all the outstanding bugs and seems to be better than GHC 7.2. Stack traces ------------ +RTS -xc now gives more information. If the exception originates from a CAF (as is common, because GHC tends to lift exceptions out to the top-level), then the RTS walks up the stack and reports the stack in the enclosing update frame(s). Result: +RTS -xc is much more useful now - but you still have to compile for profiling to get it. I've played around a little with adding 'head []' to GHC itself, and +RTS -xc does pinpoint the problem quite accurately. I plan to add more facilities for stack tracing (e.g. in GHCi) in the future. Coverage (HPC) -------------- * derived instances are now coloured yellow if they weren't used * likewise record field names * entry counts are more accurate (hpc --fun-entry-count) * tab width is now correct (markup was previously off in source with tabs) Internal changes ================ In Core, the Note constructor has been replaced by Tick (Tickish b) (Expr b) which is used to represent all the kinds of source annotation we support: profiling SCCs, HPC ticks, and GHCi breakpoints. Depending on the properties of the Tickish, different transformations apply to Tick. See CoreUtils.mkTick for details. Tickets ======= This commit closes the following tickets, test cases to follow: - Close #2552: not a bug, but the behaviour is now more intuitive (test is T2552) - Close #680 (test is T680) - Close #1531 (test is result001) - Close #949 (test is T949) - Close #2466: test case has bitrotted (doesn't compile against current version of vector-space package)
* Make a new type synonym CoreProgram = [CoreBind]Simon Peyton Jones2011-09-231-1/+1
| | | | | | | | | | | and comment its invariants in Note [CoreProgram] in CoreSyn I'm not totally convinced that CoreProgram is the right name (perhaps CoreTopBinds might better), but it is useful to have a clue that you are looking at the top-level bindings. This is only a matter of a type synonym change; no deep refactoring here.
* Use the new TrieMap to improve CSESimon Peyton Jones2011-07-291-28/+75
| | | | | | | | | | For CSE it's obviously great to have a mapping whose key is an expression. This patch makes CSE use the new CoreTrie data type. I did some very simple performance comparisions. The change in compile-time allocation is less than 1%, but it does go down! Slightly.
* Remember to substitute for type and coercion variables in the CSE passSimon Peyton Jones2011-07-271-11/+14
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* Fix CSE to do substitution properlySimon Peyton Jones2011-06-301-64/+70
| | | | It was inconsistent before, now it's right
* This BIG PATCH contains most of the work for the New Coercion RepresentationSimon Peyton Jones2011-04-191-0/+2
| | | | | | | | | | | | | | See the paper "Practical aspects of evidence based compilation in System FC" * Coercion becomes a data type, distinct from Type * Coercions become value-level things, rather than type-level things, (although the value is zero bits wide, like the State token) A consequence is that a coerion abstraction increases the arity by 1 (just like a dictionary abstraction) * There is a new constructor in CoreExpr, namely Coercion, to inject coercions into terms
* Use full equality for CSEsimonpj@microsoft.com2009-12-111-8/+12
| | | | | | | | | | | | | | | In CSE we were getting lots of apprarently-unequal expressions with the same hash code. In fact they were perfectly equal -- but we were using a cheap-and-cheerful equality tests for CoreExpr that said False for any lambda expression! This patch adds a proper equality test for Core, with alpha-renaming. It's easy to do, and will avoid silly cases of CSE failing to fire. We should get less of this: WARNING: file compiler/simplCore/CSE.lhs line 326 extendCSEnv: long list, length 18 from a compiler built with -DDEBUG
* The Big INLINE Patch: totally reorganise way that INLINE pragmas worksimonpj@microsoft.com2009-10-291-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch has been a long time in gestation and has, as a result, accumulated some extra bits and bobs that are only loosely related. I separated the bits that are easy to split off, but the rest comes as one big patch, I'm afraid. Note that: * It comes together with a patch to the 'base' library * Interface file formats change slightly, so you need to recompile all libraries The patch is mainly giant tidy-up, driven in part by the particular stresses of the Data Parallel Haskell project. I don't expect a big performance win for random programs. Still, here are the nofib results, relative to the state of affairs without the patch Program Size Allocs Runtime Elapsed -------------------------------------------------------------------------------- Min -12.7% -14.5% -17.5% -17.8% Max +4.7% +10.9% +9.1% +8.4% Geometric Mean +0.9% -0.1% -5.6% -7.3% The +10.9% allocation outlier is rewrite, which happens to have a very delicate optimisation opportunity involving an interaction of CSE and inlining (see nofib/Simon-nofib-notes). The fact that the 'before' case found the optimisation is somewhat accidental. Runtimes seem to go down, but I never kno wwhether to really trust this number. Binary sizes wobble a bit, but nothing drastic. The Main Ideas are as follows. InlineRules ~~~~~~~~~~~ When you say {-# INLINE f #-} f x = <rhs> you intend that calls (f e) are replaced by <rhs>[e/x] So we should capture (\x.<rhs>) in the Unfolding of 'f', and never meddle with it. Meanwhile, we can optimise <rhs> to our heart's content, leaving the original unfolding intact in Unfolding of 'f'. So the representation of an Unfolding has changed quite a bit (see CoreSyn). An INLINE pragma gives rise to an InlineRule unfolding. Moreover, it's only used when 'f' is applied to the specified number of arguments; that is, the number of argument on the LHS of the '=' sign in the original source definition. For example, (.) is now defined in the libraries like this {-# INLINE (.) #-} (.) f g = \x -> f (g x) so that it'll inline when applied to two arguments. If 'x' appeared on the left, thus (.) f g x = f (g x) it'd only inline when applied to three arguments. This slightly-experimental change was requested by Roman, but it seems to make sense. Other associated changes * Moving the deck chairs in DsBinds, which processes the INLINE pragmas * In the old system an INLINE pragma made the RHS look like (Note InlineMe <rhs>) The Note switched off optimisation in <rhs>. But it was quite fragile in corner cases. The new system is more robust, I believe. In any case, the InlineMe note has disappeared * The workerInfo of an Id has also been combined into its Unfolding, so it's no longer a separate field of the IdInfo. * Many changes in CoreUnfold, esp in callSiteInline, which is the critical function that decides which function to inline. Lots of comments added! * exprIsConApp_maybe has moved to CoreUnfold, since it's so strongly associated with "does this expression unfold to a constructor application". It can now do some limited beta reduction too, which Roman found was an important. Instance declarations ~~~~~~~~~~~~~~~~~~~~~ It's always been tricky to get the dfuns generated from instance declarations to work out well. This is particularly important in the Data Parallel Haskell project, and I'm now on my fourth attempt, more or less. There is a detailed description in TcInstDcls, particularly in Note [How instance declarations are translated]. Roughly speaking we now generate a top-level helper function for every method definition in an instance declaration, so that the dfun takes a particularly stylised form: dfun a d1 d2 = MkD (op1 a d1 d2) (op2 a d1 d2) ...etc... In fact, it's *so* stylised that we never need to unfold a dfun. Instead ClassOps have a special rewrite rule that allows us to short-cut dictionary selection. Suppose dfun :: Ord a -> Ord [a] d :: Ord a Then compare (dfun a d) --> compare_list a d in one rewrite, without first inlining the 'compare' selector and the body of the dfun. To support this a) ClassOps have a BuiltInRule (see MkId.dictSelRule) b) DFuns have a special form of unfolding (CoreSyn.DFunUnfolding) which is exploited in CoreUnfold.exprIsConApp_maybe Implmenting all this required a root-and-branch rework of TcInstDcls and bits of TcClassDcl. Default methods ~~~~~~~~~~~~~~~ If you give an INLINE pragma to a default method, it should be just as if you'd written out that code in each instance declaration, including the INLINE pragma. I think that it now *is* so. As a result, library code can be simpler; less duplication. The CONLIKE pragma ~~~~~~~~~~~~~~~~~~ In the DPH project, Roman found cases where he had p n k = let x = replicate n k in ...(f x)...(g x).... {-# RULE f (replicate x) = f_rep x #-} Normally the RULE would not fire, because doing so involves (in effect) duplicating the redex (replicate n k). A new experimental modifier to the INLINE pragma, {-# INLINE CONLIKE replicate #-}, allows you to tell GHC to be prepared to duplicate a call of this function if it allows a RULE to fire. See Note [CONLIKE pragma] in BasicTypes Join points ~~~~~~~~~~~ See Note [Case binders and join points] in Simplify Other refactoring ~~~~~~~~~~~~~~~~~ * I moved endPass from CoreLint to CoreMonad, with associated jigglings * Better pretty-printing of Core * The top-level RULES (ones that are not rules for locally-defined things) are now substituted on every simplifier iteration. I'm not sure how we got away without doing this before. This entails a bit more plumbing in SimplCore. * The necessary stuff to serialise and deserialise the new info across interface files. * Something about bottoming floats in SetLevels Note [Bottoming floats] * substUnfolding has moved from SimplEnv to CoreSubs, where it belongs -------------------------------------------------------------------------------- Program Size Allocs Runtime Elapsed -------------------------------------------------------------------------------- anna +2.4% -0.5% 0.16 0.17 ansi +2.6% -0.1% 0.00 0.00 atom -3.8% -0.0% -1.0% -2.5% awards +3.0% +0.7% 0.00 0.00 banner +3.3% -0.0% 0.00 0.00 bernouilli +2.7% +0.0% -4.6% -6.9% boyer +2.6% +0.0% 0.06 0.07 boyer2 +4.4% +0.2% 0.01 0.01 bspt +3.2% +9.6% 0.02 0.02 cacheprof +1.4% -1.0% -12.2% -13.6% calendar +2.7% -1.7% 0.00 0.00 cichelli +3.7% -0.0% 0.13 0.14 circsim +3.3% +0.0% -2.3% -9.9% clausify +2.7% +0.0% 0.05 0.06 comp_lab_zift +2.6% -0.3% -7.2% -7.9% compress +3.3% +0.0% -8.5% -9.6% compress2 +3.6% +0.0% -15.1% -17.8% constraints +2.7% -0.6% -10.0% -10.7% cryptarithm1 +4.5% +0.0% -4.7% -5.7% cryptarithm2 +4.3% -14.5% 0.02 0.02 cse +4.4% -0.0% 0.00 0.00 eliza +2.8% -0.1% 0.00 0.00 event +2.6% -0.0% -4.9% -4.4% exp3_8 +2.8% +0.0% -4.5% -9.5% expert +2.7% +0.3% 0.00 0.00 fem -2.0% +0.6% 0.04 0.04 fft -6.0% +1.8% 0.05 0.06 fft2 -4.8% +2.7% 0.13 0.14 fibheaps +2.6% -0.6% 0.05 0.05 fish +4.1% +0.0% 0.03 0.04 fluid -2.1% -0.2% 0.01 0.01 fulsom -4.8% +9.2% +9.1% +8.4% gamteb -7.1% -1.3% 0.10 0.11 gcd +2.7% +0.0% 0.05 0.05 gen_regexps +3.9% -0.0% 0.00 0.00 genfft +2.7% -0.1% 0.05 0.06 gg -2.7% -0.1% 0.02 0.02 grep +3.2% -0.0% 0.00 0.00 hidden -0.5% +0.0% -11.9% -13.3% hpg -3.0% -1.8% +0.0% -2.4% ida +2.6% -1.2% 0.17 -9.0% infer +1.7% -0.8% 0.08 0.09 integer +2.5% -0.0% -2.6% -2.2% integrate -5.0% +0.0% -1.3% -2.9% knights +4.3% -1.5% 0.01 0.01 lcss +2.5% -0.1% -7.5% -9.4% life +4.2% +0.0% -3.1% -3.3% lift +2.4% -3.2% 0.00 0.00 listcompr +4.0% -1.6% 0.16 0.17 listcopy +4.0% -1.4% 0.17 0.18 maillist +4.1% +0.1% 0.09 0.14 mandel +2.9% +0.0% 0.11 0.12 mandel2 +4.7% +0.0% 0.01 0.01 minimax +3.8% -0.0% 0.00 0.00 mkhprog +3.2% -4.2% 0.00 0.00 multiplier +2.5% -0.4% +0.7% -1.3% nucleic2 -9.3% +0.0% 0.10 0.10 para +2.9% +0.1% -0.7% -1.2% paraffins -10.4% +0.0% 0.20 -1.9% parser +3.1% -0.0% 0.05 0.05 parstof +1.9% -0.0% 0.00 0.01 pic -2.8% -0.8% 0.01 0.02 power +2.1% +0.1% -8.5% -9.0% pretty -12.7% +0.1% 0.00 0.00 primes +2.8% +0.0% 0.11 0.11 primetest +2.5% -0.0% -2.1% -3.1% prolog +3.2% -7.2% 0.00 0.00 puzzle +4.1% +0.0% -3.5% -8.0% queens +2.8% +0.0% 0.03 0.03 reptile +2.2% -2.2% 0.02 0.02 rewrite +3.1% +10.9% 0.03 0.03 rfib -5.2% +0.2% 0.03 0.03 rsa +2.6% +0.0% 0.05 0.06 scc +4.6% +0.4% 0.00 0.00 sched +2.7% +0.1% 0.03 0.03 scs -2.6% -0.9% -9.6% -11.6% simple -4.0% +0.4% -14.6% -14.9% solid -5.6% -0.6% -9.3% -14.3% sorting +3.8% +0.0% 0.00 0.00 sphere -3.6% +8.5% 0.15 0.16 symalg -1.3% +0.2% 0.03 0.03 tak +2.7% +0.0% 0.02 0.02 transform +2.0% -2.9% -8.0% -8.8% treejoin +3.1% +0.0% -17.5% -17.8% typecheck +2.9% -0.3% -4.6% -6.6% veritas +3.9% -0.3% 0.00 0.00 wang -6.2% +0.0% 0.18 -9.8% wave4main -10.3% +2.6% -2.1% -2.3% wheel-sieve1 +2.7% -0.0% +0.3% -0.6% wheel-sieve2 +2.7% +0.0% -3.7% -7.5% x2n1 -4.1% +0.1% 0.03 0.04 -------------------------------------------------------------------------------- Min -12.7% -14.5% -17.5% -17.8% Max +4.7% +10.9% +9.1% +8.4% Geometric Mean +0.9% -0.1% -5.6% -7.3%
* Add the notion of "constructor-like" Ids for rule-matchingsimonpj@microsoft.com2009-03-181-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds an optional CONLIKE modifier to INLINE/NOINLINE pragmas, {-# NOINLINE CONLIKE [1] f #-} The effect is to allow applications of 'f' to be expanded in a potential rule match. Example {-# RULE "r/f" forall v. r (f v) = f (v+1) #-} Consider the term let x = f v in ..x...x...(r x)... Normally the (r x) would not match the rule, because GHC would be scared about duplicating the redex (f v). However the CONLIKE modifier says to treat 'f' like a constructor in this situation, and "look through" the unfolding for x. So (r x) fires, yielding (f (v+1)). The main changes are: - Syntax - The inlinePragInfo field of an IdInfo has a RuleMatchInfo component, which records whether or not the Id is CONLIKE. Of course, this needs to be serialised in interface files too. - The occurrence analyser (OccAnal) and simplifier (Simplify) treat CONLIKE thing like constructors, by ANF-ing them - New function coreUtils.exprIsExpandable is like exprIsCheap, but additionally spots applications of CONLIKE functions - A CoreUnfolding has a field that caches exprIsExpandable - The rule matcher consults this field. See Note [Expanding variables] in Rules.lhs. On the way I fixed a lurking variable bug in the way variables are expanded. See Note [Do not expand locally-bound variables] in Rule.lhs. I also did a bit of reformatting and refactoring in Rules.lhs, so the module has more lines changed than are really different.
* Make record selectors into ordinary functionssimonpj@microsoft.com2009-01-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This biggish patch addresses Trac #2670. The main effect is to make record selectors into ordinary functions, whose unfoldings appear in interface files, in contrast to their previous existence as magic "implicit Ids". This means that the usual machinery of optimisation, analysis, and inlining applies to them, which was failing before when the selector was somewhat complicated. (Which it can be when strictness annotations, unboxing annotations, and GADTs are involved.) The change involves the following points * Changes in Var.lhs to the representation of Var. Now a LocalId can have an IdDetails as well as a GlobalId. In particular, the information that an Id is a record selector is kept in the IdDetails. While compiling the current module, the record selector *must* be a LocalId, so that it participates properly in compilation (free variables etc). This led me to change the (hidden) representation of Var, so that there is now only one constructor for Id, not two. * The IdDetails is persisted into interface files, so that an importing module can see which Ids are records selectors. * In TcTyClDecls, we generate the record-selector bindings in renamed, but not typechecked form. In this way, we can get the typechecker to add all the types and so on, which is jolly helpful especially when GADTs or type families are involved. Just like derived instance declarations. This is the big new chunk of 180 lines of code (much of which is commentary). A call to the same function, mkAuxBinds, is needed in TcInstDcls for associated types. * The typechecker therefore has to pin the correct IdDetails on to the record selector, when it typechecks it. There was a neat way to do this, by adding a new sort of signature to HsBinds.Sig, namely IdSig. This contains an Id (with the correct Name, Type, and IdDetails); the type checker uses it as the binder for the final binding. This worked out rather easily. * Record selectors are no longer "implicit ids", which entails changes to IfaceSyn.ifaceDeclSubBndrs HscTypes.implicitTyThings TidyPgm.getImplicitBinds (These three functions must agree.) * MkId.mkRecordSelectorId is deleted entirely, some 300+ lines (incl comments) of very error prone code. Happy days. * A TyCon no longer contains the list of record selectors: algTcSelIds is gone The renamer is unaffected, including the way that import and export of record selectors is handled. Other small things * IfaceSyn.ifaceDeclSubBndrs had a fragile test for whether a data constructor had a wrapper. I've replaced that with an explicit flag in the interface file. More robust I hope. * I renamed isIdVar to isId, which touched a few otherwise-unrelated files.
* Rollback INLINE patchesSimon Marlow2008-12-161-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rolling back: Fri Dec 5 16:54:00 GMT 2008 simonpj@microsoft.com * Completely new treatment of INLINE pragmas (big patch) This is a major patch, which changes the way INLINE pragmas work. Although lots of files are touched, the net is only +21 lines of code -- and I bet that most of those are comments! HEADS UP: interface file format has changed, so you'll need to recompile everything. There is not much effect on overall performance for nofib, probably because those programs don't make heavy use of INLINE pragmas. Program Size Allocs Runtime Elapsed Min -11.3% -6.9% -9.2% -8.2% Max -0.1% +4.6% +7.5% +8.9% Geometric Mean -2.2% -0.2% -1.0% -0.8% (The +4.6% for on allocs is cichelli; see other patch relating to -fpass-case-bndr-to-join-points.) The old INLINE system ~~~~~~~~~~~~~~~~~~~~~ The old system worked like this. A function with an INLINE pragam got a right-hand side which looked like f = __inline_me__ (\xy. e) The __inline_me__ part was an InlineNote, and was treated specially in various ways. Notably, the simplifier didn't inline inside an __inline_me__ note. As a result, the code for f itself was pretty crappy. That matters if you say (map f xs), because then you execute the code for f, rather than inlining a copy at the call site. The new story: InlineRules ~~~~~~~~~~~~~~~~~~~~~~~~~~ The new system removes the InlineMe Note altogether. Instead there is a new constructor InlineRule in CoreSyn.Unfolding. This is a bit like a RULE, in that it remembers the template to be inlined inside the InlineRule. No simplification or inlining is done on an InlineRule, just like RULEs. An Id can have an InlineRule *or* a CoreUnfolding (since these are two constructors from Unfolding). The simplifier treats them differently: - An InlineRule is has the substitution applied (like RULES) but is otherwise left undisturbed. - A CoreUnfolding is updated with the new RHS of the definition, on each iteration of the simplifier. An InlineRule fires regardless of size, but *only* when the function is applied to enough arguments. The "arity" of the rule is specified (by the programmer) as the number of args on the LHS of the "=". So it makes a difference whether you say {-# INLINE f #-} f x = \y -> e or f x y = e This is one of the big new features that InlineRule gives us, and it is one that Roman really wanted. In contrast, a CoreUnfolding can fire when it is applied to fewer args than than the function has lambdas, provided the result is small enough. Consequential stuff ~~~~~~~~~~~~~~~~~~~ * A 'wrapper' no longer has a WrapperInfo in the IdInfo. Instead, the InlineRule has a field identifying wrappers. * Of course, IfaceSyn and interface serialisation changes appropriately. * Making implication constraints inline nicely was a bit fiddly. In the end I added a var_inline field to HsBInd.VarBind, which is why this patch affects the type checker slightly * I made some changes to the way in which eta expansion happens in CorePrep, mainly to ensure that *arguments* that become let-bound are also eta-expanded. I'm still not too happy with the clarity and robustness fo the result. * We now complain if the programmer gives an INLINE pragma for a recursive function (prevsiously we just ignored it). Reason for change: we don't want an InlineRule on a LoopBreaker, because then we'd have to check for loop-breaker-hood at occurrence sites (which isn't currenlty done). Some tests need changing as a result. This patch has been in my tree for quite a while, so there are probably some other minor changes. M ./compiler/basicTypes/Id.lhs -11 M ./compiler/basicTypes/IdInfo.lhs -82 M ./compiler/basicTypes/MkId.lhs -2 +2 M ./compiler/coreSyn/CoreFVs.lhs -2 +25 M ./compiler/coreSyn/CoreLint.lhs -5 +1 M ./compiler/coreSyn/CorePrep.lhs -59 +53 M ./compiler/coreSyn/CoreSubst.lhs -22 +31 M ./compiler/coreSyn/CoreSyn.lhs -66 +92 M ./compiler/coreSyn/CoreUnfold.lhs -112 +112 M ./compiler/coreSyn/CoreUtils.lhs -185 +184 M ./compiler/coreSyn/MkExternalCore.lhs -1 M ./compiler/coreSyn/PprCore.lhs -4 +40 M ./compiler/deSugar/DsBinds.lhs -70 +118 M ./compiler/deSugar/DsForeign.lhs -2 +4 M ./compiler/deSugar/DsMeta.hs -4 +3 M ./compiler/hsSyn/HsBinds.lhs -3 +3 M ./compiler/hsSyn/HsUtils.lhs -2 +7 M ./compiler/iface/BinIface.hs -11 +25 M ./compiler/iface/IfaceSyn.lhs -13 +21 M ./compiler/iface/MkIface.lhs -24 +19 M ./compiler/iface/TcIface.lhs -29 +23 M ./compiler/main/TidyPgm.lhs -55 +49 M ./compiler/parser/ParserCore.y -5 +6 M ./compiler/simplCore/CSE.lhs -2 +1 M ./compiler/simplCore/FloatIn.lhs -6 +1 M ./compiler/simplCore/FloatOut.lhs -23 M ./compiler/simplCore/OccurAnal.lhs -36 +5 M ./compiler/simplCore/SetLevels.lhs -59 +54 M ./compiler/simplCore/SimplCore.lhs -48 +52 M ./compiler/simplCore/SimplEnv.lhs -26 +22 M ./compiler/simplCore/SimplUtils.lhs -28 +4 M ./compiler/simplCore/Simplify.lhs -91 +109 M ./compiler/specialise/Specialise.lhs -15 +18 M ./compiler/stranal/WorkWrap.lhs -14 +11 M ./compiler/stranal/WwLib.lhs -2 +2 M ./compiler/typecheck/Inst.lhs -1 +3 M ./compiler/typecheck/TcBinds.lhs -17 +27 M ./compiler/typecheck/TcClassDcl.lhs -1 +2 M ./compiler/typecheck/TcExpr.lhs -4 +6 M ./compiler/typecheck/TcForeign.lhs -1 +1 M ./compiler/typecheck/TcGenDeriv.lhs -14 +13 M ./compiler/typecheck/TcHsSyn.lhs -3 +2 M ./compiler/typecheck/TcInstDcls.lhs -5 +4 M ./compiler/typecheck/TcRnDriver.lhs -2 +11 M ./compiler/typecheck/TcSimplify.lhs -10 +17 M ./compiler/vectorise/VectType.hs +7 Mon Dec 8 12:43:10 GMT 2008 simonpj@microsoft.com * White space only M ./compiler/simplCore/Simplify.lhs -2 Mon Dec 8 12:48:40 GMT 2008 simonpj@microsoft.com * Move simpleOptExpr from CoreUnfold to CoreSubst M ./compiler/coreSyn/CoreSubst.lhs -1 +87 M ./compiler/coreSyn/CoreUnfold.lhs -72 +1 Mon Dec 8 17:30:18 GMT 2008 simonpj@microsoft.com * Use CoreSubst.simpleOptExpr in place of the ad-hoc simpleSubst (reduces code too) M ./compiler/deSugar/DsBinds.lhs -50 +16 Tue Dec 9 17:03:02 GMT 2008 simonpj@microsoft.com * Fix Trac #2861: bogus eta expansion Urghlhl! I "tided up" the treatment of the "state hack" in CoreUtils, but missed an unexpected interaction with the way that a bottoming function simply swallows excess arguments. There's a long Note [State hack and bottoming functions] to explain (which accounts for most of the new lines of code). M ./compiler/coreSyn/CoreUtils.lhs -16 +53 Mon Dec 15 10:02:21 GMT 2008 Simon Marlow <marlowsd@gmail.com> * Revert CorePrep part of "Completely new treatment of INLINE pragmas..." The original patch said: * I made some changes to the way in which eta expansion happens in CorePrep, mainly to ensure that *arguments* that become let-bound are also eta-expanded. I'm still not too happy with the clarity and robustness fo the result. Unfortunately this change apparently broke some invariants that were relied on elsewhere, and in particular lead to panics when compiling with profiling on. Will re-investigate in the new year. M ./compiler/coreSyn/CorePrep.lhs -53 +58 M ./configure.ac -1 +1 Mon Dec 15 12:28:51 GMT 2008 Simon Marlow <marlowsd@gmail.com> * revert accidental change to configure.ac M ./configure.ac -1 +1
* Completely new treatment of INLINE pragmas (big patch)simonpj@microsoft.com2008-12-051-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a major patch, which changes the way INLINE pragmas work. Although lots of files are touched, the net is only +21 lines of code -- and I bet that most of those are comments! HEADS UP: interface file format has changed, so you'll need to recompile everything. There is not much effect on overall performance for nofib, probably because those programs don't make heavy use of INLINE pragmas. Program Size Allocs Runtime Elapsed Min -11.3% -6.9% -9.2% -8.2% Max -0.1% +4.6% +7.5% +8.9% Geometric Mean -2.2% -0.2% -1.0% -0.8% (The +4.6% for on allocs is cichelli; see other patch relating to -fpass-case-bndr-to-join-points.) The old INLINE system ~~~~~~~~~~~~~~~~~~~~~ The old system worked like this. A function with an INLINE pragam got a right-hand side which looked like f = __inline_me__ (\xy. e) The __inline_me__ part was an InlineNote, and was treated specially in various ways. Notably, the simplifier didn't inline inside an __inline_me__ note. As a result, the code for f itself was pretty crappy. That matters if you say (map f xs), because then you execute the code for f, rather than inlining a copy at the call site. The new story: InlineRules ~~~~~~~~~~~~~~~~~~~~~~~~~~ The new system removes the InlineMe Note altogether. Instead there is a new constructor InlineRule in CoreSyn.Unfolding. This is a bit like a RULE, in that it remembers the template to be inlined inside the InlineRule. No simplification or inlining is done on an InlineRule, just like RULEs. An Id can have an InlineRule *or* a CoreUnfolding (since these are two constructors from Unfolding). The simplifier treats them differently: - An InlineRule is has the substitution applied (like RULES) but is otherwise left undisturbed. - A CoreUnfolding is updated with the new RHS of the definition, on each iteration of the simplifier. An InlineRule fires regardless of size, but *only* when the function is applied to enough arguments. The "arity" of the rule is specified (by the programmer) as the number of args on the LHS of the "=". So it makes a difference whether you say {-# INLINE f #-} f x = \y -> e or f x y = e This is one of the big new features that InlineRule gives us, and it is one that Roman really wanted. In contrast, a CoreUnfolding can fire when it is applied to fewer args than than the function has lambdas, provided the result is small enough. Consequential stuff ~~~~~~~~~~~~~~~~~~~ * A 'wrapper' no longer has a WrapperInfo in the IdInfo. Instead, the InlineRule has a field identifying wrappers. * Of course, IfaceSyn and interface serialisation changes appropriately. * Making implication constraints inline nicely was a bit fiddly. In the end I added a var_inline field to HsBInd.VarBind, which is why this patch affects the type checker slightly * I made some changes to the way in which eta expansion happens in CorePrep, mainly to ensure that *arguments* that become let-bound are also eta-expanded. I'm still not too happy with the clarity and robustness fo the result. * We now complain if the programmer gives an INLINE pragma for a recursive function (prevsiously we just ignored it). Reason for change: we don't want an InlineRule on a LoopBreaker, because then we'd have to check for loop-breaker-hood at occurrence sites (which isn't currenlty done). Some tests need changing as a result. This patch has been in my tree for quite a while, so there are probably some other minor changes.
* Comments onlysimonpj@microsoft.com2008-12-051-4/+4
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* Add (a) CoreM monad, (b) new Annotations featuresimonpj@microsoft.com2008-10-301-10/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch, written by Max Bolingbroke, does two things 1. It adds a new CoreM monad (defined in simplCore/CoreMonad), which is used as the top-level monad for all the Core-to-Core transformations (starting at SimplCore). It supports * I/O (for debug printing) * Unique supply * Statistics gathering * Access to the HscEnv, RuleBase, Annotations, Module The patch therefore refactors the top "skin" of every Core-to-Core pass, but does not change their functionality. 2. It adds a completely new facility to GHC: Core "annotations". The idea is that you can say {#- ANN foo (Just "Hello") #-} which adds the annotation (Just "Hello") to the top level function foo. These annotations can be looked up in any Core-to-Core pass, and are persisted into interface files. (Hence a Core-to-Core pass can also query the annotations of imported things.) Furthermore, a Core-to-Core pass can add new annotations (eg strictness info) of its own, which can be queried by importing modules. The design of the annotation system is somewhat in flux. It's designed to work with the (upcoming) dynamic plug-ins mechanism, but is meanwhile independently useful. Do not merge to 6.10!
* Tidy up the treatment of dead binderssimonpj@microsoft.com2008-09-201-12/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch does a lot of tidying up of the way that dead variables are handled in Core. Just the sort of thing to do on an aeroplane. * The tricky "binder-swap" optimisation is moved from the Simplifier to the Occurrence Analyser. See Note [Binder swap] in OccurAnal. This is really a nice change. It should reduce the number of simplifier iteratoins (slightly perhaps). And it means that we can be much less pessimistic about zapping occurrence info on binders in a case expression. * For example: case x of y { (a,b) -> e } Previously, each time around, even if y,a,b were all dead, the Simplifier would pessimistically zap their OccInfo, so that we can't see they are dead any more. As a result virtually no case expression ended up with dead binders. This wasn't Bad in itself, but it always felt wrong. * I added a check to CoreLint to check that a dead binder really isn't used. That showed up a couple of bugs in CSE. (Only in this sense -- they didn't really matter.) * I've changed the PprCore printer to print "_" for a dead variable. (Use -dppr-debug to see it again.) This reduces clutter quite a bit, and of course it's much more useful with the above change. * Another benefit of the binder-swap change is that I could get rid of the Simplifier hack (working, but hacky) in which the InScopeSet was used to map a variable to a *different* variable. That allowed me to remove VarEnv.modifyInScopeSet, and to simplify lookupInScopeSet so that it doesn't look for a fixpoint. This fixes no bugs, but is a useful cleanup. * Roman pointed out that Id.mkWildId is jolly dangerous, because of its fixed unique. So I've - localied it to MkCore, where it is private (not exported) - renamed it to 'mkWildBinder' to stress that you should only use it at binding sites, unless you really know what you are doing - provided a function MkCore.mkWildCase that emodies the most common use of mkWildId, and use that elsewhere So things are much better * A knock-on change is that I found a common pattern of localising a potentially global Id, and made a function for it: Id.localiseId
* Remove CoreSyn SOURCE importsMax Bolingbroke2008-08-071-1/+1
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* (F)SLIT -> (f)sLit in CSEIan Lynagh2008-04-121-1/+1
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* Don't import FastString in HsVersions.hIan Lynagh2008-03-291-0/+1
| | | | Modules that need it import it themselves instead.
* Fixed warnings in simplCore/CSETwan van Laarhoven2008-01-261-16/+17
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* White space and comments onlysimonpj@microsoft.com2008-01-041-4/+4
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* Improve documentation of INLINE, esp its interactions with other transformationssimonpj@microsoft.com2007-11-121-1/+1
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* Fix CodingStyle#Warnings URLsIan Lynagh2007-09-041-1/+1
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* Use OPTIONS rather than OPTIONS_GHC for pragmasIan Lynagh2007-09-031-2/+2
| | | | | | | Older GHCs can't parse OPTIONS_GHC. This also changes the URL referenced for the -w options from WorkingConventions#Warnings to CodingStyle#Warnings for the compiler modules.
* Add {-# OPTIONS_GHC -w #-} and some blurb to all compiler modulesIan Lynagh2007-09-011-0/+7
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* Remove mapAccumL, mapAccumR, mapAccumBIan Lynagh2007-07-021-1/+3
| | | | | mapAccumL and mapAccumR are in Data.List now. mapAccumB is unused.
* Warning policesimonpj@microsoft.com2007-05-041-1/+1
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* Less voluminous debugsimonpj@microsoft.com2007-05-031-7/+9
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* Improve hashing of expressions for CSE (reduces warnings about extendCSEnv)simonpj@microsoft.com2007-04-251-1/+3
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* Spelling in commentsimonpj@microsoft.com2006-10-181-1/+1
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* Massive patch for the first months work adding System FC to GHC #30Manuel M T Chakravarty2006-09-151-0/+1
| | | | | | | | | | | Fri Aug 4 18:13:20 EDT 2006 Manuel M T Chakravarty <chak@cse.unsw.edu.au> * Massive patch for the first months work adding System FC to GHC #30 Broken up massive patch -=chak Original log message: This is (sadly) all done in one patch to avoid Darcs bugs. It's not complete work... more FC stuff to come. A compiler using just this patch will fail dismally.
* Do not CSE in INLINE and NOINLINE thingssimonpj@microsoft.com2006-08-171-13/+65
| | | | | See extensive comments with Note [INLINE and NOINLINE] in this file.
* Reorganisation of the source treeSimon Marlow2006-04-071-0/+290
Most of the other users of the fptools build system have migrated to Cabal, and with the move to darcs we can now flatten the source tree without losing history, so here goes. The main change is that the ghc/ subdir is gone, and most of what it contained is now at the top level. The build system now makes no pretense at being multi-project, it is just the GHC build system. No doubt this will break many things, and there will be a period of instability while we fix the dependencies. A straightforward build should work, but I haven't yet fixed binary/source distributions. Changes to the Building Guide will follow, too.
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