[Git][ghc/ghc][wip/simplifier-tweaks] 19 commits: EPA: Simplify GHC/Parser.y comb4/comb5
Simon Peyton Jones (@simonpj)
gitlab at gitlab.haskell.org
Sat Jul 29 00:09:00 UTC 2023
Simon Peyton Jones pushed to branch wip/simplifier-tweaks at Glasgow Haskell Compiler / GHC
Commits:
355e1792 by Alan Zimmerman at 2023-07-26T10:17:32-04:00
EPA: Simplify GHC/Parser.y comb4/comb5
Use the HasLoc instance from Ast.hs to allow comb4/comb5 to work with
anything with a SrcSpan
Also get rid of some more now unnecessary reLoc calls.
- - - - -
9393df83 by Gavin Zhao at 2023-07-26T10:18:16-04:00
compiler: make -ddump-asm work with wasm backend NCG
Fixes #23503.
Now the `-ddump-asm` flag is respected in the wasm backend
NCG, so developers can directly view the generated ASM instead of
needing to pass `-S` or `-keep-tmp-files` and manually find & open
the assembly file.
Ideally, we should be able to output the assembly files in smaller
chunks like in other NCG backends. This would also make dumping assembly
stats easier. However, this would require a large refactoring, so for
short-term debugging purposes I think the current approach works fine.
Signed-off-by: Gavin Zhao <git at gzgz.dev>
- - - - -
79463036 by Krzysztof Gogolewski at 2023-07-26T10:18:54-04:00
llvm: Restore accidentally deleted code in 0fc5cb97
Fixes #23711
- - - - -
20db7e26 by Rodrigo Mesquita at 2023-07-26T10:19:33-04:00
configure: Default missing options to False when preparing ghc-toolchain Targets
This commit fixes building ghc with 9.2 as the boostrap compiler.
The ghc-toolchain patch assumed all _STAGE0 options were available, and
forgot to account for this missing information in 9.2.
Ghc 9.2 does not have in settings whether ar supports -l, hence can't
report it with --info (unliked 9.4 upwards).
The fix is to default the missing information (we default "ar supports
-l" and other missing options to False)
- - - - -
fac9e84e by Naïm Favier at 2023-07-26T10:20:16-04:00
docs: Fix typo
- - - - -
503fd647 by Bartłomiej Cieślar at 2023-07-26T17:23:10-04:00
This MR is an implementation of the proposal #516.
It adds a warning -Wincomplete-record-selectors for usages of a record
field access function (either a record selector or getField @"rec"),
while trying to silence the warning whenever it can be sure that a constructor
without the record field would not be invoked (which would otherwise cause
the program to fail). For example:
data T = T1 | T2 {x :: Bool}
f a = x a -- this would throw an error
g T1 = True
g a = x a -- this would not throw an error
h :: HasField "x" r Bool => r -> Bool
h = getField @"x"
j :: T -> Bool
j = h -- this would throw an error because of the `HasField`
-- constraint being solved
See the tests DsIncompleteRecSel* and TcIncompleteRecSel for more examples of the warning.
See Note [Detecting incomplete record selectors] in GHC.HsToCore.Expr for implementation details
- - - - -
af6fdf42 by Arnaud Spiwack at 2023-07-26T17:23:52-04:00
Fix user-facing label in MR template
- - - - -
5d45b92a by Matthew Pickering at 2023-07-27T05:46:46-04:00
ci: Test bootstrapping configurations with full-ci and on marge batches
There have been two incidents recently where bootstrapping has been
broken by removing support for building with 9.2.*.
The process for bumping the minimum required version starts with bumping
the configure version and then other CI jobs such as the bootstrap jobs
have to be updated. We must not silently bump the minimum required
version.
Now we are running a slimmed down validate pipeline it seems worthwile
to test these bootstrap configurations in the full-ci pipeline.
- - - - -
25d4fee7 by Matthew Pickering at 2023-07-27T05:46:46-04:00
bootstrap: Remove ghc-9_2_* plans
We are anticipating shortly making it necessary to use ghc-9.4 to boot
the compiler.
- - - - -
2f66da16 by Matthew Pickering at 2023-07-27T05:46:46-04:00
Update bootstrap plans for ghc-platform and ghc-toolchain dependencies
Fixes #23735
- - - - -
c8c6eab1 by Matthew Pickering at 2023-07-27T05:46:46-04:00
bootstrap: Disable -selftest flag from bootstrap plans
This saves on building one dependency (QuickCheck) which is unecessary
for bootstrapping.
- - - - -
a80ca086 by Bodigrim at 2023-07-27T05:47:26-04:00
Link reference paper and package from System.Mem.{StableName,Weak}
- - - - -
a5319358 by David Knothe at 2023-07-28T13:13:10-04:00
Update Match Datatype
EquationInfo currently contains a list of the equation's patterns together with a CoreExpr that is to be evaluated after a successful match on this equation.
All the match-functions only operate on the first pattern of an equation - after successfully matching it, match is called recursively on the tail of the pattern list.
We can express this more clearly and make the code a little more elegant by updating the datatype of EquationInfo as follows:
data EquationInfo
= EqnMatch { eqn_pat = Pat GhcTc, eqn_rest = EquationInfo }
| EqnDone { eqn_rhs = MatchResult CoreExpr }
An EquationInfo now explicitly exposes its first pattern which most functions operate on, and exposes the equation that remains after processing the first pattern. An EqnDone signifies an empty equation where the CoreExpr can now be evaluated.
- - - - -
86ad1af9 by David Binder at 2023-07-28T13:13:53-04:00
Improve documentation for Data.Fixed
- - - - -
f8fa1d08 by Ben Gamari at 2023-07-28T13:14:31-04:00
ghc-prim: Use C11 atomics
Previously `ghc-prim`'s atomic wrappers used the legacy `__sync_*`
family of C builtins. Here we refactor these to rather use the
appropriate C11 atomic equivalents, allowing us to be more explicit
about the expected ordering semantics.
- - - - -
af04ebee by Simon Peyton Jones at 2023-07-28T22:54:13+01:00
Make the occurrence analyser smarter about join points
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. But the geom mean stay 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
Metric Increase:
T18140
T9961
T18282
T18698a
T18698b
T19695
- - - - -
a2ebb7d7 by Simon Peyton Jones at 2023-07-28T23:33:58+01:00
Several improvements to the handling of coercions
* Make `mkSymCo` and `mkInstCo` smarter
Fixes #23642
* Fix return role of `SelCo` in the coercion optimiser.
Fixes #23617
* Make the coercion optimiser `opt_trans_rule` work better for newtypes
Fixes #23619
- - - - -
13b2156a by Simon Peyton Jones at 2023-07-28T23:33:58+01:00
Simplifier improvements
This MR started as: allow the simplifer to do more in one pass,
arising from places I could see the simplifier taking two iterations
where one would do. But it turned into a larger project, because
these changes unexpectedly made inlining blow up, especially join
points in deeply-nested cases.
The net result is good: a 2% improvement in compile time. The table
below shows changes over 1%.
The main changes are:
* The SimplEnv now has a seInlineDepth field, which says how deep
in unfoldings we are. See Note [Inline depth] in Simplify.Env
* Avoid repeatedly simplifying coercions.
see Note [Avoid re-simplifying coercions] in Simplify.Iteration
As you'll see from the Note, this makes use of the seInlineDepth.
* Allow Simplify.Utils.postInlineUnconditionally to inline variables
that are used exactly once. See Note [Post-inline for single-use things].
* Allow Simplify.Iteration.simplAuxBind to inline used-once things.
This is another part of Note [Post-inline for single-use things], and
is really good for reducing simplifier iterations in situations like
case K e of { K x -> blah }
wher x is used once in blah.
* Make GHC.Core.SimpleOpt.exprIsConApp_maybe do some simple case
elimination. Note [Case elim in exprIsConApp_maybe]
* When making join points, don't do so if the join point is so small
it will immediately be inlined. See Note [Duplicating alternatives]
* Do not add an unfolding to a join point at birth. This is a tricky one
and has a long Note [Do not add unfoldings to join points at birth]
It shows up in two places
- In `mkDupableAlt` do not add an inlining
- (trickier) In `simplLetUnfolding` don't add an unfolding for a
fresh join point
I am not fully satisifed with this, but it works and is well documented.
* Many new or rewritten Notes. E.g. Note [Avoiding simplifying repeatedly]
I discovered that GHC.HsToCore.Pmc.Solver.Types.trvVarInfo was very
delicately balanced. It's a small, heavily used, overloaded function
and it's important that it inlines. By a fluke it was before, but at
various times in my journey it stopped doing so. So I added an INLINE
pragma to it.
Metrics: compile_time/bytes allocated
------------------------------------------------
CoOpt_Singletons(normal) -4.3% GOOD
LargeRecord(normal) -23.3% GOOD
PmSeriesS(normal) -2.4%
T11195(normal) -1.7%
T12227(normal) -20.0% GOOD
T12545(normal) -5.4%
T13253-spj(normal) -50.7% GOOD
T13386(normal) -5.1% GOOD
T14766(normal) -2.4% GOOD
T15164(normal) -1.7%
T15304(normal) +1.0%
T15630(normal) -7.7%
T15630a(normal) NEW
T15703(normal) -7.5% GOOD
T16577(normal) -5.1% GOOD
T17516(normal) -3.6%
T18223(normal) -16.8% GOOD
T18282(normal) -1.5%
T18304(normal) +1.9%
T21839c(normal) -3.5% GOOD
T3064(normal) -1.5%
T5030(normal) -16.2% GOOD
T5321Fun(normal) -1.6%
T6048(optasm) -2.1% GOOD
T8095(normal) -6.1% GOOD
T9630(normal) -5.1% GOOD
WWRec(normal) -1.6%
geo. mean -2.1%
minimum -50.7%
maximum +1.9%
Metric Decrease:
CoOpt_Singletons
LargeRecord
T12227
T13253-spj
T13386
T14766
T15703
T16577
T18223
T21839c
T5030
T6048
T8095
T9630
- - - - -
0a5a2092 by Simon Peyton Jones at 2023-07-28T23:33:58+01:00
Improve postInlineUnconditionally
This commit adds two things to postInlineUnconditionally:
1. Do not postInlineUnconditionally join point, ever.
Doing so does not reduce allocation, which is the main point,
and with join points that are used a lot it can bloat code.
See point (1) of Note [Duplicating join points] in
GHC.Core.Opt.Simplify.Iteration.
2. Do not postInlineUnconditionally a strict (demanded) binding.
It will not allocate a thunk (it'll turn into a case instead)
so again the main point of inlining it doesn't hold. Better
to check per-call-site.
- - - - -
18 changed files:
- .gitlab-ci.yml
- .gitlab/merge_request_templates/Default.md
- compiler/GHC/CmmToAsm.hs
- compiler/GHC/CmmToAsm/Wasm.hs
- compiler/GHC/CmmToLlvm/CodeGen.hs
- compiler/GHC/Core/Coercion.hs
- compiler/GHC/Core/Coercion/Opt.hs
- compiler/GHC/Core/ConLike.hs
- compiler/GHC/Core/Lint.hs
- compiler/GHC/Core/Opt/CSE.hs
- compiler/GHC/Core/Opt/DmdAnal.hs
- compiler/GHC/Core/Opt/Exitify.hs
- compiler/GHC/Core/Opt/FloatIn.hs
- compiler/GHC/Core/Opt/FloatOut.hs
- compiler/GHC/Core/Opt/OccurAnal.hs
- compiler/GHC/Core/Opt/SetLevels.hs
- compiler/GHC/Core/Opt/Simplify/Env.hs
- compiler/GHC/Core/Opt/Simplify/Inline.hs
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/2687f3950d8f3f0d7f9e3d8f17e4ab9adf6ad09e...0a5a2092c07a5e759993a8dd0d5ce82898a811f7
--
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/2687f3950d8f3f0d7f9e3d8f17e4ab9adf6ad09e...0a5a2092c07a5e759993a8dd0d5ce82898a811f7
You're receiving this email because of your account on gitlab.haskell.org.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/ghc-commits/attachments/20230728/b20707cf/attachment-0001.html>
More information about the ghc-commits
mailing list