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* Documented yet undocumented dump flags #18641Benjamin Maurer2021-09-281-0/+38
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* Add `-dsuppress-core-sizes` flag (#20342)Sylvain Henry2021-09-281-0/+8
| | | | | This flag is used to remove the output of core stats per binding in Core dumps.
* Minor doc fixesKrzysztof Gogolewski2021-09-081-0/+6
| | | | | | | | | | | | | - Fix markup in 9.4 release notes - Document -ddump-cs-trace - Mention that ImpredicativeTypes is really supported only since 9.2 - Remove "There are some restrictions on the use of unboxed tuples". This used to be a list, but all those restrictions were removed. - Mark -fimplicit-import-qualified as documented - Remove "The :main and :run command" - duplicated verbatim in options - Avoid calling "main" a function (cf. #7816) - Update System.getArgs: the old location was before hierarchical modules - Note that multiplicity multiplication is not supported (#20319)
* Introduce -ddump-verbose-inliningsBen Gamari2021-04-271-5/+10
| | | | | | | | Previously -ddump-inlinings and -dverbose-core2core used in conjunction would have the side-effect of dumping additional information about all inlinings considered by the simplifier. However, I have sometimes wanted this inlining information without the firehose of information produced by -dverbose-core2core. Introduce a new dump flag for this purpose.
* Add a flag to dump the FastString tableSylvain Henry2021-03-031-0/+7
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* Document flag -dasm-lint in debugging.rstBenjamin Maurer2021-01-101-0/+7
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* Implement -ddump-c-backend argumentBen Gamari2020-11-221-0/+9
| | | | To dump output of the C backend.
* Update user's guide entry on demand analysis and worker/wrapperSebastian Graf2020-11-201-5/+10
| | | | | | | | | The demand signature notation has been undocumented for a long time. The only source to understand it, apart from reading the `Outputable` instance, has been an outdated wiki page. Since the previous commits have reworked the demand lattice, I took it as an opportunity to also write some documentation about notation.
* Fix -ddump-stg flagSylvain Henry2020-08-211-1/+9
| | | | | | | -ddump-stg was dumping the initial STG (just after Core-to-STG pass) which was misleading because we want the final STG to know if a function allocates or not. Now we have a new flag -ddump-stg-from-core for this and -ddump-stg is deprecated.
* Linear types (#15981)Krzysztof Gogolewski2020-06-171-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the first step towards implementation of the linear types proposal (https://github.com/ghc-proposals/ghc-proposals/pull/111). It features * A language extension -XLinearTypes * Syntax for linear functions in the surface language * Linearity checking in Core Lint, enabled with -dlinear-core-lint * Core-to-core passes are mostly compatible with linearity * Fields in a data type can be linear or unrestricted; linear fields have multiplicity-polymorphic constructors. If -XLinearTypes is disabled, the GADT syntax defaults to linear fields The following items are not yet supported: * a # m -> b syntax (only prefix FUN is supported for now) * Full multiplicity inference (multiplicities are really only checked) * Decent linearity error messages * Linear let, where, and case expressions in the surface language (each of these currently introduce the unrestricted variant) * Multiplicity-parametric fields * Syntax for annotating lambda-bound or let-bound with a multiplicity * Syntax for non-linear/multiple-field-multiplicity records * Linear projections for records with a single linear field * Linear pattern synonyms * Multiplicity coercions (test LinearPolyType) A high-level description can be found at https://ghc.haskell.org/trac/ghc/wiki/LinearTypes/Implementation Following the link above you will find a description of the changes made to Core. This commit has been authored by * Richard Eisenberg * Krzysztof Gogolewski * Matthew Pickering * Arnaud Spiwack With contributions from: * Mark Barbone * Alexander Vershilov Updates haddock submodule.
* Fix spelling mistakes and typosbuggymcbugfix2020-05-211-1/+1
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* Add "ddump-cmm-opt" as alias for "ddump-opt-cmm".Andreas Klebinger2020-04-221-1/+7
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* Add outputable instances for the types in GHC.Iface.Ext.Types, add -ddump-hieZubin Duggal2020-04-031-0/+6
| | | | | | | | | | | | | | | | | flag to dump pretty printed contents of the .hie file Metric Increase: hie002 Because of the regression on i386: compile_time/bytes allocated increased from i386-linux-deb9 baseline @ HEAD~10: Expected hie002 (normal) compile_time/bytes allocated: 583014888.0 +/-10% Lower bound hie002 (normal) compile_time/bytes allocated: 524713399 Upper bound hie002 (normal) compile_time/bytes allocated: 641316377 Actual hie002 (normal) compile_time/bytes allocated: 877986292 Deviation hie002 (normal) compile_time/bytes allocated: 50.6 % *** unexpected stat test failure for hie002(normal)
* Document the units of -ddump-timingsMaximilian Tagher2020-03-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | Right now, in the output of -ddump-timings to a file, you can't tell what the units are: ``` CodeGen [TemplateTestImports]: alloc=22454880 time=14.597 ``` I believe bytes/milliseconds are the correct units, but confirmation would be appreciated. I'm basing it off of this snippet from `withTiming'`: ``` when (verbosity dflags >= 2 && prtimings == PrintTimings) $ liftIO $ logInfo dflags (defaultUserStyle dflags) (text "!!!" <+> what <> colon <+> text "finished in" <+> doublePrec 2 time <+> text "milliseconds" <> comma <+> text "allocated" <+> doublePrec 3 (realToFrac alloc / 1024 / 1024) <+> text "megabytes") ``` which implies time is in milliseconds, and allocations in bytes (which divided by 1024 would be KB, and again would be MB)
* Revert "users-guide: Document -ddump-srts"Ömer Sinan Ağacan2020-02-161-6/+0
| | | | | | | | This reverts commit 8cf646d36b02b8ea1c289cb52781c9171853b514. The flag was removed by 16d643cf. [ci skip]
* users-guide: Document -ddump-srtsBen Gamari2020-02-141-0/+6
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* Separate CPR analysis from the Demand analyserwip/sep-cprSebastian Graf2020-02-121-0/+12
| | | | | | | | | | | | | | | | | | | The reasons for that can be found in the wiki: https://gitlab.haskell.org/ghc/ghc/wikis/nested-cpr/split-off-cpr We now run CPR after demand analysis (except for after the final demand analysis run just before code gen). CPR got its own dump flags (`-ddump-cpr-anal`, `-ddump-cpr-signatures`), but not its own flag to activate/deactivate. It will run with `-fstrictness`/`-fworker-wrapper`. As explained on the wiki page, this step is necessary for a sane Nested CPR analysis. And it has quite positive impact on compiler performance: Metric Decrease: T9233 T9675 T9961 T15263
* Improve/fix -fcatch-bottoms documentationÖmer Sinan Ağacan2020-02-011-6/+13
| | | | | | | | | | | | | | | Old documentation suggests that -fcatch-bottoms only adds a default alternative to bottoming case expression, but that's not true. We use a very simplistic "is exhaustive" check and add default alternatives to any case expression that does not cover all constructors of the type. In case of GADTs this simple check assumes all constructors should be covered, even the ones ruled out by the type of the scrutinee. Update the documentation to reflect this. (Originally noticed in #17648) [ci skip]
* Add new flag for unarised STG dumpsÖmer Sinan Ağacan2019-10-231-2/+8
| | | | | | | | | | | | | Previously -ddump-stg would dump pre and post-unarise STGs. Now we have a new flag for post-unarise STG and -ddump-stg only dumps coreToStg output. STG dump flags after this commit: - -ddump-stg: Dumps CoreToStg output - -ddump-stg-unarised: Unarise output - -ddump-stg-final: STG right before code gen (includes CSE and lambda lifting)
* users-guide: Fix links and formats for GHC 8.10Takenobu Tani2019-09-231-1/+1
| | | | | | This commit only fixes links and markdown syntax. [skip ci]
* Add a new flag -dno-typeable-binds for debuggingÖmer Sinan Ağacan2019-09-081-0/+12
| | | | | See the user manual entry -- this helps when debugging as generated Core gets smaller without these bindings.
* Change behaviour of -ddump-cmm-verbose to dump each Cmm pass output to a ↵nineonine2019-07-261-2/+9
| | | | separate file and add -ddump-cmm-verbose-by-proc to keep old behaviour (#16930)
* Add -ddump-stg-final to dump stg as it is used for codegen.klebinger.andreas@gmx.at2019-04-121-0/+5
| | | | | Intermediate STG does not contain free variables which can be useful sometimes. So adding a flag to dump that info.
* Fix #15953 by consistently using dumpIfSet_dyn to print debug outputChaitanya Koparkar2018-11-291-0/+42
| | | | | | | | | | | | | | | | | | | | | | | | Summary: In some modules we directly dump the debugging output to STDOUT via 'putLogMsg', 'printInfoForUser' etc. However, if `-ddump-to-file` is enabled, that output should be written to a file. Easily fixed. Certain tests (T3017, Roles3, T12763 etc.) expect part of the output generated by `-ddump-types` to be in 'PprUser' style. However, generally we want all other debugging output to use 'PprDump' style. `traceTcRn` and `traceTcRnForUser` help us accomplish this. This patch also documents some missing flags in the users guide. Reviewers: RyanGlScott, bgamari, hvr Reviewed By: RyanGlScott Subscribers: rwbarton, carter GHC Trac Issues: #15953 Differential Revision: https://phabricator.haskell.org/D5382
* NCG: New code layout algorithm.Andreas Klebinger2018-11-171-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This patch implements a new code layout algorithm. It has been tested for x86 and is disabled on other platforms. Performance varies slightly be CPU/Machine but in general seems to be better by around 2%. Nofib shows only small differences of about +/- ~0.5% overall depending on flags/machine performance in other benchmarks improved significantly. Other benchmarks includes at least the benchmarks of: aeson, vector, megaparsec, attoparsec, containers, text and xeno. While the magnitude of gains differed three different CPUs where tested with all getting faster although to differing degrees. I tested: Sandy Bridge(Xeon), Haswell, Skylake * Library benchmark results summarized: * containers: ~1.5% faster * aeson: ~2% faster * megaparsec: ~2-5% faster * xml library benchmarks: 0.2%-1.1% faster * vector-benchmarks: 1-4% faster * text: 5.5% faster On average GHC compile times go down, as GHC compiled with the new layout is faster than the overhead introduced by using the new layout algorithm, Things this patch does: * Move code responsilbe for block layout in it's own module. * Move the NcgImpl Class into the NCGMonad module. * Extract a control flow graph from the input cmm. * Update this cfg to keep it in sync with changes during asm codegen. This has been tested on x64 but should work on x86. Other platforms still use the old codelayout. * Assign weights to the edges in the CFG based on type and limited static analysis which are then used for block layout. * Once we have the final code layout eliminate some redundant jumps. In particular turn a sequences of: jne .foo jmp .bar foo: into je bar foo: .. Test Plan: ci Reviewers: bgamari, jmct, jrtc27, simonmar, simonpj, RyanGlScott Reviewed By: RyanGlScott Subscribers: RyanGlScott, trommler, jmct, carter, thomie, rwbarton GHC Trac Issues: #15124 Differential Revision: https://phabricator.haskell.org/D4726
* fix -ddump-asm descriptionAlp Mestanogullari2018-08-301-1/+1
| | | | | | | | | | | | | | Summary: It was missing some words. Test Plan: None (docs only) Reviewers: bgamari, monoidal Reviewed By: monoidal Subscribers: rwbarton, carter Differential Revision: https://phabricator.haskell.org/D5102
* users guide: Mention -fprint-typechecker-elaboration in -ddump-tc docsBen Gamari2018-07-061-2/+5
| | | | | | | | | | Reviewers: mpickering Reviewed By: mpickering Subscribers: mpickering, rwbarton, thomie, carter Differential Revision: https://phabricator.haskell.org/D4898
* Add -ddump-rtti to user's guide and man pageÖmer Sinan Ağacan2018-06-291-0/+6
| | | | | | | | Reviewers: bgamari Subscribers: rwbarton, thomie, carter Differential Revision: https://phabricator.haskell.org/D4903
* Explain why opt-cmm is not dumped by ddump-cmm-verbose.klebinger.andreas@gmx.at2018-06-221-3/+5
| | | | | | | | | | | | | | | | | | We just update the docs to reflect the state of affairs. opt-cmm is run by the NCG backend so not always run. ddump-cmm-verbose only dumps passes of the cmm pipeline so it's not included there. [skip-ci] Test Plan: doc change Reviewers: bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie, carter Differential Revision: https://phabricator.haskell.org/D4879
* Typofixes in docs and comments [ci skip]Gabor Greif2018-06-181-2/+2
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* Fix documentation for `-dth-dec-file`Nathan Collins2018-06-151-3/+4
| | | | | The docs said that it took a file argument, as in `-dth-dec-file=<file>`, but it does not take a file argument!
* Document the fact that cmm dumps won't show unreachable blocks.klebinger.andreas@gmx.at2018-06-041-0/+3
| | | | | | | | | | Reviewers: bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie, carter Differential Revision: https://phabricator.haskell.org/D4788
* Allow aligning of cmm procs at specific boundryklebinger.andreas@gmx.at2018-06-031-0/+11
| | | | | | | | | | | | | | | | | | | | Allows to align CmmProcs at the given boundries. It makes performance usually worse but can be helpful to limit the effect of a unrelated function B becoming faster/slower after changing function A. Test Plan: ci, using it. Reviewers: bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie, carter GHC Trac Issues: #15148 Differential Revision: https://phabricator.haskell.org/D4706
* vectorise: Put it out of its miseryBen Gamari2018-06-021-13/+0
| | | | | | | | | | | | | | | | | | | | | Poor DPH and its vectoriser have long been languishing; sadly it seems there is little chance that the effort will be rekindled. Every few years we discuss what to do with this mass of code and at least once we have agreed that it should be archived on a branch and removed from `master`. Here we do just that, eliminating heaps of dead code in the process. Here we drop the ParallelArrays extension, the vectoriser, and the `vector` and `primitive` submodules. Test Plan: Validate Reviewers: simonpj, simonmar, hvr, goldfire, alanz Reviewed By: simonmar Subscribers: goldfire, rwbarton, thomie, mpickering, carter Differential Revision: https://phabricator.haskell.org/D4761
* users-guide: Fix various issues in debugging flags sectionBen Gamari2018-05-301-8/+6
| | | | | | | | | | Reviewers: ggreif Reviewed By: ggreif Subscribers: rwbarton, thomie, carter, ggreif Differential Revision: https://phabricator.haskell.org/D4750
* Typofix in manual [ci skip]Gabor Greif2018-05-291-1/+1
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* Add new debugging flag -dinline-checkBen Gamari2018-03-251-0/+14
| | | | | | | | | | | | | | | | | | | | | | | This flag reports a summary of the inlining decision for identifiers prefixed by the flag's argument. For example, `-dinline-check foo` will report why definitions whose prefix is `foo` are inlined or not. Previously the only way to get this information was to pass a combination of `-dverbose-core2core` and `-ddump-inlinings`. This combination led to a log of 12 million lines in a module of about 200 lines I recently had to apply it to. This flag provides a much more direct way to find the occurence you care about. Reviewers: osa1, dfeuer, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie, carter Differential Revision: https://phabricator.haskell.org/D4458
* Implement -dword-hex-literalsAndrew Martin2018-03-191-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | Provide flag for showing showing Word# and Word64# as hexadecimal when dumping GHC core. The only affects Word, not Int, and it prefixes the hexadecimal with enough zeroes to make the total character count a power of two. For example: - 0x0C0C instead of 0xC0C - 0x00BA00BA instead of 0xBA00BA This also affects the presentation of Word# and Word64# in GHC's error messages. It is not expected that the flag will be used for this, but it is a side-effect worth noting. Test Plan: none Reviewers: bgamari, simonpj Reviewed By: simonpj Subscribers: simonpj, mpickering, rwbarton, thomie, carter, andrewthad GHC Trac Issues: #14872 Differential Revision: https://phabricator.haskell.org/D4465
* Introduce the flag -dsuppress-timestamps to avoid timestamps in dumps.Andreas Klebinger2018-02-251-1/+8
| | | | | | | | | | | | | | | | | This makes it easier to diff dumps which are otherwise identical. Also updated the description of -dsuppress-all as parts of these also apply to stages other than core. Test Plan: Looking at dump result. Reviewers: bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie, carter Differential Revision: https://phabricator.haskell.org/D4429
* StgLint overhaulÖmer Sinan Ağacan2018-02-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Remove all type checks - Check two STG invariants (no unboxed let bindings, variables defined before used) and post-unarisation invariants. See the module header and #14787. This version validates with `-dstg-lint` added to `GhcStage2HcOpts` and `GhcLibHcOpts` and `EXTRA_HC_OPTS`. Unarise changes: - `unariseConArgBinder` and `unariseFunArgBinder` functions were almost the same; only difference was when unarising fun args we keep void args while in con args we drop them. A new function `unariseArgBinder` added with a `Bool` argument for whether we're unarising a con arg. `unariseConArgBinder` and `unariseFunArgBinder` are now defined as unariseConArgBinder = unarsieArgBinder True -- data con unariseFunArgBinder = unariseArgBinder False -- not data con - A bug in `unariseConArgBinder` and `unariseFunArgBinder` (which are just calls to `unariseArgBinder` now) that invalidated the post-unarise invariants when the argument has single type rep (i.e. `length (typePrimRep x) == 1`) fixed. This isn't a correctness issue (it's fine not to unarise if a variable is already represented as single value), but it triggers StgLint. Test Plan: - Pass testsuite with `-dstg-lint` [done] - Boot stage2 (including libraries) with `-dstg-lint` [done] Reviewers: simonpj, bgamari Reviewed By: bgamari Subscribers: duog, rwbarton, thomie, carter GHC Trac Issues: #14787 Differential Revision: https://phabricator.haskell.org/D4404
* Add -ddump-ds-preoptSimon Peyton Jones2018-02-011-3/+8
| | | | | | | | | | | | | This allows you to see the output immediately after desugaring but before any optimisation. I've wanted this for some time, but I was triggered into action by Trac #13032 comment:9. Interestingly, the change means that with -dcore-lint we will now Lint the output before the very simple optimiser; and this showed up Trac #14749. But that's not the fault of -ddump-ds-preopt!
* Rename -frule-check to -drule-check and documentMatthew Pickering2018-01-151-0/+13
| | | | | | | | | | Reviewers: bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie, carter Differential Revision: https://phabricator.haskell.org/D4256
* Prevent "C--" translating to "C–" in the User's Guide.Steven Shaw2018-01-021-34/+34
| | | | i.e. escape "--" so that it doesn't translate to an "en dash".
* Document -ddump-timingsBen Gamari2017-11-161-0/+5
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* Introduce -dsuppress-stg-free-vars flagBen Gamari2017-11-021-0/+12
| | | | | | | | | | | | | | This breaks out control over STG free variable list output from -dppr-debug into its own distinct flag. This makes it more discoverable and easier to change independently from other dump output. Test Plan: Validate Reviewers: austin Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4140
* Add -falignment-sanitization flagBen Gamari2017-10-291-0/+7
| | | | | | | | | | | | | | | | | | | Here we add a flag to instruct the native code generator to add alignment checks in all info table dereferences. This is helpful in catching pointer tagging issues. Thanks to @jrtc27 for uncovering the tagging issues on Sparc which inspired this flag. Test Plan: Validate Reviewers: simonmar, austin, erikd Reviewed By: simonmar Subscribers: rwbarton, trofi, thomie, jrtc27 Differential Revision: https://phabricator.haskell.org/D4101
* Manual: The -ddump-cmm-* flags had a wrong spelling in the manualJoachim Breitner2017-10-281-10/+22
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* Fix grammaros in commentsGabor Greif2017-10-171-1/+1
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* users-guide: Clarify -ddump-asm-regalloc-stages documentationBen Gamari2017-10-161-2/+4
| | | | [skip ci]
* users guide: Eliminate redundant :category: tags in debugging.rstBen Gamari2017-10-161-85/+4
| | | | The categories in this file are defined in flags.py.
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