- Feb 05, 2024
-
-
This MR fixes #24251. See Note [Case-to-let for strictly-used binders] in GHC.Core.Opt.Simplify.Iteration, plus #24251, for lots of discussion. Final Nofib changes over 0.1%: +----------------------------------------- | imaginary/digits-of-e2 -2.16% | imaginary/rfib -0.15% | real/fluid -0.10% | real/gamteb -1.47% | real/gg -0.20% | real/maillist +0.19% | real/pic -0.23% | real/scs -0.43% | shootout/n-body -0.41% | shootout/spectral-norm -0.12% +======================================== | geom mean -0.05% Pleasingly, overall executable size is down by just over 1%. Compile times (in perf/compiler) wobble around a bit +/- 0.5%, but the geometric mean is -0.1% which seems good.
-
- Feb 03, 2024
-
-
Apoorv Ingle authored- Fixes #18324 #20020 #23147 #22788 #15598 #22086 #21206 - The change is detailed in - Note [Expanding HsDo with HsExpansion] in `GHC.Tc.Gen.Do` - Note [Doing HsExpansion in the Renamer vs Typechecker] in `GHC.Rename.Expr` expains the rational of doing expansions in type checker as opposed to in the renamer - Adds new datatypes: - `GHC.Hs.Expr.XXExprGhcRn`: new datatype makes this expansion work easier 1. Expansion bits for Expressions, Statements and Patterns in (`ExpandedThingRn`) 2. `PopErrCtxt` a special GhcRn Phase only artifcat to pop the previous error message in the error context stack - `GHC.Basic.Origin` now tracks the reason for expansion in case of Generated This is useful for type checking cf. `GHC.Tc.Gen.Expr.tcExpr` case for `HsLam` - Kills `HsExpansion` and `HsExpanded` as we have inlined them in `XXExprGhcRn` and `XXExprGhcTc` - Ensures warnings such as 1. Pattern match checks 2. Failable patterns 3. non-() return in body statements are preserved - Kill `HsMatchCtxt` in favor of `TcMatchAltChecker` - Testcases: * T18324 T20020 T23147 T22788 T15598 T22086 * T23147b (error message check), * DoubleMatch (match inside a match for pmc check) * pattern-fails (check pattern match with non-refutable pattern, eg. newtype) * Simple-rec (rec statements inside do statment) * T22788 (code snippet from #22788) * DoExpanion1 (Error messages for body statments) * DoExpansion2 (Error messages for bind statements) * DoExpansion3 (Error messages for let statements) Also repoint haddock to the right submodule so that the test (haddockHypsrcTest) pass Metric Increase 'compile_time/bytes allocated': T9020 The testcase is a pathalogical example of a `do`-block with many statements that do nothing. Given that we are expanding the statements into function binds, we will have to bear a (small) 2% cost upfront in the compiler to unroll the statements.
-
- Jan 31, 2024
-
-
Simon Peyton Jones authored
This fixes #24370 by making decomposeRuleLhs undertand dictionary /functions/ as well as plain /dictionaries/
-
- Jan 20, 2024
-
-
- Jan 08, 2024
-
-
... and suggest -ddump-dmdanal and -ddump-dmd-signatures instead
-
- Dec 12, 2023
-
-
...and use it to generate slightly better code when dataToTag# is used at a "small data type" where there is no need to mess with "is_too_big_tag" or potentially look at an info table. Metric Decrease: T18304
-
- Dec 08, 2023
-
-
This patch does two things, to fix #23209: * It improves SpecConstr so that it no longer quantifies over coercion variables. See Note [SpecConstr and casts] * It improves the rule matcher to deal nicely with the case where the rule does not quantify over coercion variables, but the the template has a cast in it. See Note [Casts in the template]
-
This partially fixes #24229. See the new Note [Pattern duplicate elimination] in SpecConstr
-
- Dec 06, 2023
-
-
StgCse can revive dead binders: case foo of dead { Foo x y -> Foo x y; ... } ===> case foo of dead { Foo x y -> dead; ... } -- dead is no longer dead So we must zap occurrence information on case binders. Fix #14895 and #24233
-
- Nov 26, 2023
-
-
We no longer need the EpAnnNotUsed constructor for EpAnn, as we can represent an unused annotation with an anchor having a EpaDelta of zero, and empty comments and annotations. This simplifies code handling annotations considerably. Updates haddock submodule Metric Increase: parsing001
-
- Nov 17, 2023
-
-
Use rep size rather than rep count to compute the size. Fixes #22309
-
- Nov 09, 2023
-
-
Closes #20532. This implements CLC proposal 104: https://github.com/haskell/core-libraries-committee/issues/104 The design is explained in Note [DataToTag overview] in GHC.Tc.Instance.Class. This replaces the existing `dataToTag#` primop. These metric changes are not "real"; they represent Unique-related flukes triggering on a different set of jobs than they did previously. See also #19414. Metric Decrease: T13386 T8095 Metric Increase: T13386 T8095 Co-authored-by:
Simon Peyton Jones <simon.peytonjones@gmail.com>
-
- Nov 05, 2023
-
-
- Oct 10, 2023
-
-
The motivation for the flag is given in #21917.
-
- Oct 05, 2023
-
-
- Oct 04, 2023
-
-
- Sep 28, 2023
-
-
Fixes #24014.
-
- Sep 16, 2023
-
-
As the Lint error in #23952 showed, the function adjustJoinPointType was failing to adjust the FunTyFlag when adjusting the type. I don't think this caused the seg-fault reported in the ticket, but it is definitely. This patch fixes it. It is tricky to come up a small test case; Krzysztof came up with this one, but it only triggers a failure in GHC 9.6.
-
- Sep 13, 2023
-
-
Issue #23922 showed that GHC was bogusly eta-reducing a join point. We should never eta-reduce (\x -> j x) to j, if j is a join point. It is extremly difficult to trigger this bug. It took me 45 mins of trying to make a small tests case, here immortalised as T23922a.
-
When the user adds a SPEC argument to a function, they are informing us that they expect the function to be specialised. However, previously this instruction could be preempted by the specialised-argument limit (sc_max_args). Fix this. This fixes #14003.
-
- Sep 07, 2023
-
-
In the Lint failure in #23938, we start with a coercion Refl :: T a ~R T a, and call mkSelCo (SelTyCon 1 nominal) Refl. The function incorrectly returned Refl :: a ~R a. The returned role should be nominal, according to the SelCo rule: co : (T s1..sn) ~r0 (T t1..tn) r = tyConRole tc r0 i ---------------------------------- SelCo (SelTyCon i r) : si ~r ti In this test case, r is nominal while r0 is representational.
-
- Aug 28, 2023
-
-
Simon says this was fixed by commit 59202c80 Author: Sebastian Graf <sebastian.graf@kit.edu> Date: Fri Mar 31 17:35:22 2023 +0200 CorePrep: Eliminate EmptyCase and unsafeEqualityProof in CoreToStg instead We eliminate EmptyCase by way of `coreToStg (Case e _ _ []) = coreToStg e` now. The main reason is that it plays far better in conjunction with eta expansion (as we aim to do for arguments in CorePrep, #23083), because we can discard any arguments, `(case e of {}) eta == case e of {}`, whereas in `(e |> co) eta` it's impossible to discard the argument.
-
- Aug 09, 2023
-
-
Previously, we'd only eta expand let bindings and lambdas, now we'll also eta expand arguments such as in T23083: ```hs g f h = f (h `seq` (h $)) ``` Unless `-fpedantic-bottoms` is set, we'll now transform to ```hs g f h = f (\eta -> h eta) ``` in CorePrep. See the new `Note [Eta expansion of arguments in CorePrep]` for the details. We only do this optimisation with -O2 because we saw 2-3% ghc/alloc regressions in T4801 and T5321FD. Fixes #23083.
-
A minor improvement to pretty-printing
-
- Aug 03, 2023
-
-
Gergő Érdi authored
incoherent instances Fixes #23287
-
- Jul 30, 2023
-
-
This MR addresses #22404. There is a big Note Note [Occurrence analysis for join points] that explains it all. Significant changes * New field occ_join_points in OccEnv * The NonRec case of occAnalBind splits into two cases: one for existing join points (which does the special magic for Note [Occurrence analysis for join points], and one for other bindings. * mkOneOcc adds in info from occ_join_points. * All "bring into scope" activity is centralised in the new function `addInScope`. * I made a local data type LocalOcc for use inside the occurrence analyser It is like OccInfo, but lacks IAmDead and IAmALoopBreaker, which in turn makes computationns over it simpler and more efficient. * I found quite a bit of allocation in GHC.Core.Rules.getRules so I optimised it a bit. More minor changes * I found I was using (Maybe Arity) a lot, so I defined a new data type JoinPointHood and used it everwhere. This touches a lot of non-occ-anal files, but it makes everything more perspicuous. * Renamed data constructor WithUsageDetails to WUD, and WithTailUsageDetails to WTUD This also fixes #21128, on the way. --------- Compiler perf ----------- I spent quite a time on performance tuning, so even though it does more than before, the occurrence analyser runs slightly faster on average. Here are the compile-time allocation changes over 0.5% CoOpt_Read(normal) ghc/alloc 766,025,520 754,561,992 -1.5% CoOpt_Singletons(normal) ghc/alloc 759,436,840 762,925,512 +0.5% LargeRecord(normal) ghc/alloc 1,814,482,440 1,799,530,456 -0.8% PmSeriesT(normal) ghc/alloc 68,159,272 67,519,720 -0.9% T10858(normal) ghc/alloc 120,805,224 118,746,968 -1.7% T11374(normal) ghc/alloc 164,901,104 164,070,624 -0.5% T11545(normal) ghc/alloc 79,851,808 78,964,704 -1.1% T12150(optasm) ghc/alloc 73,903,664 71,237,544 -3.6% GOOD T12227(normal) ghc/alloc 333,663,200 331,625,864 -0.6% T12234(optasm) ghc/alloc 52,583,224 52,340,344 -0.5% T12425(optasm) ghc/alloc 81,943,216 81,566,720 -0.5% T13056(optasm) ghc/alloc 294,517,928 289,642,512 -1.7% T13253-spj(normal) ghc/alloc 118,271,264 59,859,040 -49.4% GOOD T15164(normal) ghc/alloc 1,102,630,352 1,091,841,296 -1.0% T15304(normal) ghc/alloc 1,196,084,000 1,166,733,000 -2.5% T15630(normal) ghc/alloc 148,729,632 147,261,064 -1.0% T15703(normal) ghc/alloc 379,366,664 377,600,008 -0.5% T16875(normal) ghc/alloc 32,907,120 32,670,976 -0.7% T17516(normal) ghc/alloc 1,658,001,888 1,627,863,848 -1.8% T17836(normal) ghc/alloc 395,329,400 393,080,248 -0.6% T18140(normal) ghc/alloc 71,968,824 73,243,040 +1.8% T18223(normal) ghc/alloc 456,852,568 453,059,088 -0.8% T18282(normal) ghc/alloc 129,105,576 131,397,064 +1.8% T18304(normal) ghc/alloc 71,311,712 70,722,720 -0.8% T18698a(normal) ghc/alloc 208,795,112 210,102,904 +0.6% T18698b(normal) ghc/alloc 230,320,736 232,697,976 +1.0% BAD T19695(normal) ghc/alloc 1,483,648,128 1,504,702,976 +1.4% T20049(normal) ghc/alloc 85,612,024 85,114,376 -0.6% T21839c(normal) ghc/alloc 415,080,992 410,906,216 -1.0% GOOD T4801(normal) ghc/alloc 247,590,920 250,726,272 +1.3% T6048(optasm) ghc/alloc 95,699,416 95,080,680 -0.6% T783(normal) ghc/alloc 335,323,384 332,988,120 -0.7% T9233(normal) ghc/alloc 709,641,224 685,947,008 -3.3% GOOD T9630(normal) ghc/alloc 965,635,712 948,356,120 -1.8% T9675(optasm) ghc/alloc 444,604,152 428,987,216 -3.5% GOOD T9961(normal) ghc/alloc 303,064,592 308,798,800 +1.9% BAD WWRec(normal) ghc/alloc 503,728,832 498,102,272 -1.1% geo. mean -1.0% minimum -49.4% maximum +1.9% In fact these figures seem to vary between platforms; generally worse on i386 for some reason. The Windows numbers vary by 1% espec in benchmarks where the total allocation is low. But the geom mean stays solidly negative, which is good. The "increase/decrease" list below covers all platforms. The big win on T13253-spj comes because it has a big nest of join points, each occurring twice in the next one. The new occ-anal takes only one iteration of the simplifier to do the inlining; the old one took four. Moreover, we get much smaller code with the new one: New: Result size of Tidy Core = {terms: 429, types: 84, coercions: 0, joins: 14/14} Old: Result size of Tidy Core = {terms: 2,437, types: 304, coercions: 0, joins: 10/10} --------- Runtime perf ----------- No significant changes in nofib results, except a 1% reduction in compiler allocation. Metric Decrease: CoOpt_Read T13253-spj T9233 T9630 T9675 T12150 T21839c LargeRecord MultiComponentModulesRecomp T10421 T13701 T10421 T13701 T12425 Metric Increase: T18140 T9961 T18282 T18698a T18698b T19695
-
- Jul 22, 2023
- Jul 15, 2023
-
-
This patch finally (I hope) nails the question of whether (forall a. ty) and (forall a -> ty) are `eqType`: they aren't! There is a long discussion in #22762, plus useful Notes: * Note [ForAllTy and type equality] in GHC.Core.TyCo.Compare * Note [Comparing visiblities] in GHC.Core.TyCo.Compare * Note [ForAllCo] in GHC.Core.TyCo.Rep It also establishes a helpful new invariant for ForAllCo, and ForAllTy, when the bound variable is a CoVar:in that case the visibility must be coreTyLamForAllTyFlag. All this is well documented in revised Notes.
-
- Jul 13, 2023
-
-
Found by Simon in ghc/ghc#23567 (comment 507834) The testcase isn't ideal because it doesn't detect the bug in master, unless doNotUnbox is removed as in ghc/ghc#23567 (comment 507692). But I have confirmed that with that modification, it fails before and passes afterwards.
-
- Jul 06, 2023
-
-
Fixes #23272
-
- Jul 05, 2023
-
-
Fixes #23267
-
Currently the Semigroup stimes cycle is resolved in GHC.Base by importing stimes implementations from a hs-boot file. Resolve the cycle using hs-boot files for required classes (Num, Integral) instead. Now stimes can be defined directly in GHC.Base, making inlining and specialization possible. This leads to some new boot files for `GHC.Num` and `GHC.Real`, the methods for those are only used to implement `stimes` so it doesn't appear that these boot files will introduce any new performance traps. Metric Decrease: T13386 T8095 Metric Increase: T13253 T13386 T18698a T18698b T19695 T8095 -
Numerous tests make use of CUSKs (complete user-supplied kinds), a legacy feature scheduled for deprecation. In order to proceed with the said deprecation, the tests have been updated to use SAKS instead (standalone kind signatures). This also allows us to remove the Haskell2010 language pragmas that were added in 115cd3c8 to work around the lack of CUSKs in GHC2021.
-
- Jun 29, 2023
-
-
Polymorphic specialisation has led to a number of hard to diagnose incorrect runtime result bugs (see #23469, #23109, #21229, #23445) so this commit introduces a flag `-fpolymorhphic-specialisation` which allows users to turn on this experimental optimisation if they are willing to buy into things going very wrong. Ticket #23469
-
- Jun 21, 2023
-
-
Sylvain Henry authored
- Add ghc-interp.js bootstrap script for the JS interpreter - Interactively link and execute iserv code from the ghci package - Incrementally load and run JS code for splices into the running iserv Co-authored-by:Luite Stegeman <stegeman@gmail.com>
-
- Jun 14, 2023
-
-
- Jun 13, 2023
-
-
Tracking ticket: #23059 This runs compile_and_run tests with optimised code with bytecode interpreter Changed submodules: hpc, process Co-authored-by:Torsten Schmits <git@tryp.io>
-
- May 23, 2023
-
-
The function GHC.Core.Opt.Simplify.Utils.abstractFloats was carelessly calling lookupIdSubst_maybe on a CoVar; but a precondition of the latter is being given an Id. In fact it's harmless to call it on a CoVar, but still, the precondition on lookupIdSubst_maybe makes sense, so I added a test for CoVars. This avoids a crash in a DEBUG compiler, but otherwise has no effect. Fixes #23426.
-
- May 15, 2023
-
-
Confusingly, the testsuite mangled the error to say "stray /". We also migrate some tests from grep to grep -E, as it seems the author actually wanted an "POSIX extended" (a.k.a. sane) regex. Background: POSIX specifies 2 "regex" syntaxen: "basic" and "extended". Of these, only "extended" syntax is actually a regular expression. Furthermore, "basic" syntax is inconsistent in its use of the '\' character — sometimes it escapes a regex metacharacter, but sometimes it unescapes it, i.e. it makes an otherwise normal character become a metacharacter. This baffles me and it seems also the authors of these tests. Also, the regex(7) man page (at least on Linux) says "basic" syntax is obsolete. Nearly all modern tools and libraries are consistent in this use of the '\' character (of which many use "extended" syntax by default).
-
