summaryrefslogtreecommitdiff
path: root/compiler
Commit message (Collapse)AuthorAgeFilesLines
* cmm/CBE: Fix a few more zip usesBen Gamari2017-11-061-3/+8
| | | | | | | | | | | | | | | Ensure that we don't consider lists of equal length to be equal when they are not. I noticed these while working on the fix for #14361. Reviewers: austin, simonmar, michalt Reviewed By: michalt Subscribers: rwbarton, thomie GHC Trac Issues: #14361 Differential Revision: https://phabricator.haskell.org/D4153
* cmm/CBE: Fix comparison between blocks of different lengthsBen Gamari2017-11-061-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously CBE computed equality by taking the lists of middle nodes of the blocks being compared and zipping them together. It would then map over this list with the equality relation, and accumulate the result. However, this is completely wrong: Consider what will happen when we compare a block with no middle nodes with one with one or more. The result of `zip` will be empty and consequently the pass may conclude that the two are indeed equivalent (if their last nodes also match). This is very bad and the cause of #14361. The solution I chose was just to write out an explicit recursion, like I distinctly recall considering doing when I first wrote this code. Unfortunately I was feeling clever at the time. Unfortunately this case was just rare enough not to be triggered by the testsuite. I still need to find a testcase that doesn't have external dependencies. Test Plan: Need to find a more minimal testcase Reviewers: austin, simonmar, michalt Reviewed By: michalt Subscribers: michalt, rwbarton, thomie, hvr GHC Trac Issues: #14361 Differential Revision: https://phabricator.haskell.org/D4152
* Clean up comments about match algorithm a bit.klebinger.andreas@gmx.at2017-11-031-66/+43
|
* Deserialize all function TypeRepsDavid Feuer2017-11-021-7/+12
| | | | | | | | | | | | | | Previously, we could only deserialize `TypeRep (a -> b)` if both `a` and `b` had kind `Type`. Now, we do it regardless of their runtime representations. Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4137
* llvmGen: Pass vector arguments in vector registers by defaultBen Gamari2017-11-021-2/+3
| | | | | | | | | | | | | | | Earlier this year Edward Kmett requested [1] that we enable passing of vector values in vector registers by default. The GHC calling convention changes have been in LLVM for a number of years now so let's just flip the switch. [1] https://mail.haskell.org/pipermail/ghc-devs/2017-March/013905.html Reviewers: austin Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4142
* CmmSink: Use a IntSet instead of a listalexbiehl2017-11-021-7/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CmmProcs which have *lots* of local variables take a considerable amount of time in CmmSink. This was noticed by @tdammers in #7258 while compiling files with large records (~200-400 fields). Before: ``` Sun Oct 29 19:58 2017 Time and Allocation Profiling Report (Final) ghc-stage2 +RTS -p -RTS -B/Users/alexbiehl/git/ghc/inplace/lib /Users/alexbiehl/Downloads/W2.hs -fforce-recomp -O2 total time = 26.00 secs (25996 ticks @ 1000 us, 1 processor) total alloc = 14,921,627,912 bytes (excludes profiling overheads) COST CENTRE MODULE SRC %time %alloc sink CmmPipeline compiler/cmm/CmmPipeline.hs:(104,13)-(105,59) 55.7 15.9 SimplTopBinds SimplCore compiler/simplCore/SimplCore.hs:761:39-74 19.5 30.6 FloatOutwards SimplCore compiler/simplCore/SimplCore.hs:471:40-66 4.2 9.0 RegAlloc-linear AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(658,27)-(660,55) 4.0 11.1 pprNativeCode AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(529,37)-(530,65) 2.8 6.3 NewStranal SimplCore compiler/simplCore/SimplCore.hs:480:40-63 1.6 3.7 OccAnal SimplCore compiler/simplCore/SimplCore.hs:(739,22)-(740,67) 1.5 3.5 StgCmm HscMain compiler/main/HscMain.hs:(1426,13)-(1427,62) 1.2 2.4 regLiveness AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(591,17)-(593,52) 1.2 1.9 genMachCode AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(580,17)-(582,62) 0.9 1.8 NativeCodeGen CodeOutput compiler/main/CodeOutput.hs:171:18-78 0.9 2.1 CoreTidy HscMain compiler/main/HscMain.hs:1253:27-67 0.8 1.9 ``` After: ``` Sun Oct 29 19:18 2017 Time and Allocation Profiling Report (Final) ghc-stage2 +RTS -p -RTS -B/Users/alexbiehl/git/ghc/inplace/lib /Users/alexbiehl/Downloads/W2.hs -fforce-recomp -O2 total time = 13.31 secs (13307 ticks @ 1000 us, 1 processor) total alloc = 15,772,184,488 bytes (excludes profiling overheads) COST CENTRE MODULE SRC %time %alloc SimplTopBinds SimplCore compiler/simplCore/SimplCore.hs:761:39-74 38.3 29.0 sink CmmPipeline compiler/cmm/CmmPipeline.hs:(104,13)-(105,59) 13.2 20.3 RegAlloc-linear AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(658,27)-(660,55) 8.3 10.5 FloatOutwards SimplCore compiler/simplCore/SimplCore.hs:471:40-66 8.1 8.5 pprNativeCode AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(529,37)-(530,65) 5.4 5.9 NewStranal SimplCore compiler/simplCore/SimplCore.hs:480:40-63 3.1 3.5 OccAnal SimplCore compiler/simplCore/SimplCore.hs:(739,22)-(740,67) 2.9 3.3 StgCmm HscMain compiler/main/HscMain.hs:(1426,13)-(1427,62) 2.3 2.3 regLiveness AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(591,17)-(593,52) 2.1 1.8 NativeCodeGen CodeOutput compiler/main/CodeOutput.hs:171:18-78 1.7 2.0 genMachCode AsmCodeGen compiler/nativeGen/AsmCodeGen.hs:(580,17)-(582,62) 1.6 1.7 CoreTidy HscMain compiler/main/HscMain.hs:1253:27-67 1.4 1.8 foldNodesBwdOO Hoopl.Dataflow compiler/cmm/Hoopl/Dataflow.hs:(397,1)-(403,17) 1.1 0.8 ``` Reviewers: austin, bgamari, simonmar Reviewed By: bgamari Subscribers: duog, rwbarton, thomie, tdammers GHC Trac Issues: #7258 Differential Revision: https://phabricator.haskell.org/D4145
* Introduce -dsuppress-stg-free-vars flagBen Gamari2017-11-022-3/+9
| | | | | | | | | | | | | | 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
* TcRnDriver: Bracket family instance consistency output in -ddump-rn-traceBen Gamari2017-11-021-1/+2
| | | | | | | | Reviewers: austin Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4141
* Use proper Unique for Namealexbiehl2017-11-021-12/+11
| | | | | | | | | | | | | I noticed this while tinkering in haddock. This might be a relict from ancient times where newtypes wouldn't optimize well. Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4146
* Implement the basics of hex floating point literalsIavor Diatchki2017-11-023-6/+80
| | | | | | | | | | | | | | | | | | | | | | | Implement hexadecmial floating point literals. The digits of the mantissa are hexadecimal. The exponent is written in base 10, and the base for the exponentiation is 2. Hexadecimal literals look a lot like ordinary decimal literals, except that they use hexadecmial digits, and the exponent is written using `p` rather than `e`. The specification of the feature is available here: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0004-hexFloats.rst For a discussion of the various choices: https://github.com/ghc-proposals/ghc-proposals/pull/37 Reviewers: mpickering, goldfire, austin, bgamari, hvr Reviewed By: bgamari Subscribers: mpickering, thomie Differential Revision: https://phabricator.haskell.org/D3066
* PPC NCG: Impl branch prediction, atomic ops.Peter Trommler2017-11-023-61/+201
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement AtomicRMW ops, atomic read, atomic write in PowerPC native code generator. Also implement branch prediction because we need it in atomic ops anyway. This patch improves the issue in #12537 a bit but does not fix it entirely. The fallback operations for atomicread and atomicwrite in libraries/ghc-prim/cbits/atomic.c are incorrect. This patch avoids those functions by implementing the operations directly in the native code generator. This is also what the x86/amd64 NCG and the LLVM backend do. Test Plan: validate on AIX and PowerPC (32-bit) Linux Reviewers: erikd, hvr, austin, bgamari, simonmar Reviewed By: hvr, bgamari Subscribers: rwbarton, thomie GHC Trac Issues: #12537 Differential Revision: https://phabricator.haskell.org/D3984
* Implement the EmptyDataDeriving proposalRyan Scott2017-11-024-32/+51
| | | | | | | | | | | | | | | | | | | | | | | | | This implements the `EmptyDataDeriving` proposal put forth in https://github.com/ghc-proposals/ghc-proposals/blob/dbf51608/proposals/0006-deriving-empty.rst. This has two major changes: * The introduction of an `EmptyDataDeriving` extension, which permits directly deriving `Eq`, `Ord`, `Read`, and `Show` instances for empty data types. * An overhaul in the code that is emitted in derived instances for empty data types. To see an overview of the changes brought forth, refer to the changes to the 8.4.1 release notes. Test Plan: ./validate Reviewers: bgamari, dfeuer, austin, hvr, goldfire Reviewed By: bgamari Subscribers: rwbarton, thomie GHC Trac Issues: #7401, #10577, #13117 Differential Revision: https://phabricator.haskell.org/D4047
* Tidy up IfaceEqualityTyConSimon Peyton Jones2017-10-312-45/+44
| | | | | | | | | | | | | This commit commit 85aa1f4253163985fe07d172f8da73b784bb7b4b Date: Sun Oct 29 20:48:19 2017 -0400 Fix #14390 by making toIfaceTyCon aware of equality was a bit over-complicated. This patch simplifies the (horribly ad-hoc) treatement of IfaceEqualityTyCon, and documents it better. No visible change in behaviour.
* Add Note [Setting the right in-scope set]Simon Peyton Jones2017-10-301-1/+26
|
* Catch a few more typos in commentsGabor Greif2017-10-306-11/+11
|
* Typofixes in commentsGabor Greif2017-10-303-3/+3
|
* Typofix in panicGabor Greif2017-10-301-1/+1
|
* Fix typo in accessor nameGabor Greif2017-10-304-6/+6
| | | | and in comments
* A bit more tc-tracingSimon Peyton Jones2017-10-301-2/+8
|
* Allow packing constructor fieldsMichal Terepeta2017-10-2913-105/+317
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is another step for fixing #13825 and is based on D38 by Simon Marlow. The change allows storing multiple constructor fields within the same word. This currently applies only to `Float`s, e.g., ``` data Foo = Foo {-# UNPACK #-} !Float {-# UNPACK #-} !Float ``` on 64-bit arch, will now store both fields within the same constructor word. For `WordX/IntX` we'll need to introduce new primop types. Main changes: - We now use sizes in bytes when we compute the offsets for constructor fields in `StgCmmLayout` and introduce padding if necessary (word-sized fields are still word-aligned) - `ByteCodeGen` had to be updated to correctly construct the data types. This required some new bytecode instructions to allow pushing things that are not full words onto the stack (and updating `Interpreter.c`). Note that we only use the packed stuff when constructing data types (i.e., for `PACK`), in all other cases the behavior should not change. - `RtClosureInspect` was changed to handle the new layout when extracting subterms. This seems to be used by things like `:print`. I've also added a test for this. - I deviated slightly from Simon's approach and use `PrimRep` instead of `ArgRep` for computing the size of fields. This seemed more natural and in the future we'll probably want to introduce new primitive types (e.g., `Int8#`) and `PrimRep` seems like a better place to do that (where we already have `Int64Rep` for example). `ArgRep` on the other hand seems to be more focused on calling functions. Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com> Test Plan: ./validate Reviewers: bgamari, simonmar, austin, hvr, goldfire, erikd Reviewed By: bgamari Subscribers: maoe, rwbarton, thomie GHC Trac Issues: #13825 Differential Revision: https://phabricator.haskell.org/D3809
* Fix #14390 by making toIfaceTyCon aware of equalityRyan Scott2017-10-291-0/+6
| | | | | | | | | | | | | | | | | | | | GHC was panicking when pretty-printing a heterogeneous equality type constructor (#14390) because the function which produced the type constructor, `toIfaceTyCon`, wasn't attaching the appropriate `IfaceTyConSort` for equality type constructors, which is `IfaceEqualityTyCon`. This is fixed easily enough. Test Plan: make test TEST=T14390 Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie GHC Trac Issues: #14390 Differential Revision: https://phabricator.haskell.org/D4132
* Turn `compareByteArrays#` out-of-line primop into inline primopalexbiehl2017-10-299-2/+49
| | | | | | | | | | | | Depends on D4090 Reviewers: austin, bgamari, erikd, simonmar, alexbiehl Reviewed By: bgamari Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4091
* Add -falignment-sanitization flagBen Gamari2017-10-297-3/+48
| | | | | | | | | | | | | | | | | | | 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
* Implement a dedicated exitfication pass #14152Joachim Breitner2017-10-2911-6/+478
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The idea is described in #14152, and can be summarized: Float the exit path out of a joinrec, so that the simplifier can do more with it. See the test case for a nice example. The floating goes against what the simplifier usually does, hence we need to be careful not inline them back. The position of exitification in the pipeline was chosen after a small amount of experimentation, but may need to be improved. For example, exitification can allow rewrite rules to fire, but for that it would have to happen before the `simpl_phases`. Perf.haskell.org reports these nice performance wins: Nofib allocations fannkuch-redux 78446640 - 99.92% 64560 k-nucleotide 109466384 - 91.32% 9502040 simple 72424696 - 5.96% 68109560 Nofib instruction counts fannkuch-redux 1744331636 - 3.86% 1676999519 k-nucleotide 2318221965 - 6.30% 2172067260 scs 1978470869 - 3.35% 1912263779 simple 669858104 - 3.38% 647206739 spectral-norm 186423292 - 5.37% 176411536 Differential Revision: https://phabricator.haskell.org/D3903
* simplNonRecJoinPoint: Handle Shadowing correctlyJoachim Breitner2017-10-291-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, (since 33452df), simplNonRecJoinPoint would do the wrong thing in the presence of shadowing: It analyzed the RHS of a join binding with the environment for the body. In particular, with foo x = join x = x * x in x where there is shadowing, it renames the inner x to x1, and should produce foo x = join x1 = x * x in x1 but because the substitution (x ↦ x1) is also used on the RHS we get the bogus foo x = join x1 = x1 * x1 in x1 Fixed this by adding a `rhs_se` parameter, analogous to `simplNonRecE` and `simplLazyBind`. Differential Revision: https://phabricator.haskell.org/D4130
* Make tagForCon non-linearBartosz Nitka2017-10-272-4/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Computing the number of constructors for TyCon is linear in the number of constructors. That's wasteful if all you want to check is if that number is smaller than what fits in tag bits (usually 8 things). What this change does is to use a function that can determine the ineqaulity without computing the size. This improves compile time on a module with a data type that has 10k constructors. The variance in total time is (suspiciously) high, but going by the best of 3 the numbers are 8.186s vs 7.511s. For 1000 constructors the difference isn't noticeable: 0.646s vs 0.624s. The hot spots were cgDataCon and cgEnumerationTyCon where tagForCon is called in a loop. One alternative would be to pass down the size. Test Plan: harbormaster Reviewers: bgamari, simonmar, austin Reviewed By: simonmar Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4116
* ApplicativeDo: handle BodyStmt (#12143)Simon Marlow2017-10-277-22/+73
| | | | | | | | | | | | | | | | | | | Summary: It's simple to treat BodyStmt just like a BindStmt with a wildcard pattern, which is enough to fix #12143 without going all the way to using `<*` and `*>` (#10892). Test Plan: * new test cases in `ado004.hs` * validate Reviewers: niteria, simonpj, bgamari, austin, erikd Subscribers: rwbarton, thomie GHC Trac Issues: #12143 Differential Revision: https://phabricator.haskell.org/D4128
* Fix an exponential-blowup case in SpecConstrSimon Peyton Jones2017-10-271-20/+33
| | | | | | | | | Trac #14379 showed a case where use of "forcing" to do "damn the torpedos" specialisation without resource limits (which 'vector' does a lot) led to exponential blowup. The fix is easy. Finding it wasn't. See Note [Forcing specialisation] and the one-line change in decreaseSpecCount.
* Add more pprTrace to SpecConstr (debug only)Simon Peyton Jones2017-10-271-3/+11
|
* Factor out readField (#14364)Tobias Dammers2017-10-252-18/+27
| | | | | | | | | | | | | | | | | | | Improves compiler performance of deriving Read instances, as suggested in the issue. Additionally, we introduce `readSymField`, a companion to `readField` that parses symbol-type fields (where the field name is a symbol, e.g. `(#)`, rather than an alphanumeric identifier. The decision between these two functions is made a compile time, because we already know which one we need based on the field name. Reviewers: austin, hvr, bgamari, RyanGlScott Reviewed By: bgamari Subscribers: RyanGlScott, rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4108
* Fix a bug in 'alexInputPrevChar'Alec Theriault2017-10-251-25/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The lexer hacks around unicode by squishing any character into a 'Word8' and then storing the actual character in its state. This happens at 'alexGetByte'. That is all and well, but we ought to be careful that the characters we retrieve via 'alexInputPrevChar' also fit this convention. In fact, #13986 exposes nicely what can go wrong: the regex in the left context of the type application rule uses the '$idchar' character set which relies on the unicode hack. However, a left context corresponds to a call to 'alexInputPrevChar', and we end up passing full blown unicode characters to '$idchar', despite it not being equipped to deal with these. Test Plan: Added a regression test case Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie GHC Trac Issues: #13986 Differential Revision: https://phabricator.haskell.org/D4105
* Implement `-Wpartial-fields` warning (#7169)Daishi Nakajima2017-10-252-1/+45
| | | | | | | | | | | | | | | | | Warning on declaring a partial record selector. However, disable warn with field names that start with underscore. Test Plan: Added 1 test case. Reviewers: austin, bgamari, simonpj Reviewed By: bgamari, simonpj Subscribers: goldfire, simonpj, duog, rwbarton, thomie GHC Trac Issues: #7169 Differential Revision: https://phabricator.haskell.org/D4083
* Performance improvements linear regAlloc (#7258)Tobias Dammers2017-10-251-11/+13
| | | | | | | | | | | | | | | | | | | | | | | When allocating and potentially spilling registers, we need to check the desired allocations against current allocations to decide where we can spill to, cq. which allocations we can toss and if so, how. Previously, this was done by walking the Cartesian product of the current allocations (`assig`) and the allocations to keep (`keep`), which has quadratic complexity. This patch introduces two improvements: 1. pre-filter the `assig` list, because we are only interested in two types of allocations (in register, and in register+memory), which will only make up a small and constant portion of the list; and 2. use set / map operations instead of lists, which reduces algorithmic complexity. Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4109
* Fix space leak in BinIface.getSymbolTableDouglas Wilson2017-10-251-10/+23
| | | | | | | | | | | | | | | | | | | | | | | | Replace a call to mapAccumR, which uses linear stack space, with a gadget that uses constant space. Remove an unused parameter from fromOnDiskName. The tests T1292_imports and T4239 are now reporting imported names in a different order. I don't completely understand why, but I presume it is because the symbol tables are now read more strictly. The new order seems better in T1792_imports, and equally random in T4239. There are several performance test improvements. Test Plan: ./validate Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: alexbiehl, rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4124
* Make layLeft and reduceDoc stricter (#7258)Tobias Dammers2017-10-251-6/+6
| | | | | | | | | | | | | | Making the pretty-printer based assembly output stricter in strategically chosen locations produces a minor performance improvement when compiling large derived Read instance (on the order of 5-10%). Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4111
* typecheck: Clarify errors mentioned in #14385Ben Gamari2017-10-251-6/+6
|
* Revert "Update Win32 version for GHC 8.4."Tamar Christina2017-10-251-1/+1
| | | | | | This reverts commit 561bdca16e2fe88d0b96fc10098955eabca81bba. submodule
* Update Win32 version for GHC 8.4.Tamar Christina2017-10-251-1/+1
| | | | | | | | | | | | | | | | Summary: Update to Win32 2.6 which is the expected version release for 8.4 This bumps the required submodule s as well. Test Plan: ./validate Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4117
* Include usg_file_hash in ghc --show-iface outputSimon Marlow2017-10-241-1/+2
| | | | | | | | | | | | | | Summary: Otherwise we can get an iface hash difference, but no indication of what caused it in the --show-iface output. Test Plan: Harbourmaster Reviewers: austin, bgamari, erikd Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4115
* Temporary fix to Trac #14380Simon Peyton Jones2017-10-241-4/+17
| | | | | | | | This fix replaces an utterly bogus error message with a decent one, rejecting a pattern synonym with a list pattern and rebindable syntax. Not hard to fix properly, but I'm going to wait for a willing volunteer and/or more user pressure.
* Comments onlySimon Peyton Jones2017-10-231-1/+1
|
* Improve kick-out in the constraint solverSimon Peyton Jones2017-10-205-124/+186
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch was provoked by Trac #14363. Turned out that we were kicking out too many constraints in TcSMonad.kickOutRewritable, and that mean that the work-list never became empty: infinite loop! That in turn made me look harder at the Main Theorem in Note [Extending the inert equalities]. Main changes * Replace TcType.isTyVarExposed by TcType.isTyVarHead. The over-agressive isTyVarExposed is what caused Trac #14363. See Note [K3: completeness of solving] in TcSMonad. * TcType.Make anyRewriteableTyVar role-aware. In particular, a ~R ty cannot rewrite b ~R f a See Note [anyRewriteableTyVar must be role-aware]. That means it has to be given a role argument, which forces a little refactoring. I think this change is fixing a bug that hasn't yet been reported. The actual reported bug is handled by the previous bullet. But this change is definitely the Right Thing The main changes are in TcSMonad.kick_out_rewritable, and in TcType (isTyVarExposed ---> isTyVarHead). I did a little unforced refactoring: * Use the cc_eq_rel field of a CTyEqCan when it is available, rather than recomputing it. * Define eqCanRewrite :: EqRel -> EqRel -> EqRel, and use it, instead of duplicating its logic
* Comments and white spaceSimon Peyton Jones2017-10-202-1/+4
|
* Outputable: Add pprTraceExceptionBen Gamari2017-10-191-1/+11
|
* Add Functor Bag instanceBen Gamari2017-10-191-0/+3
|
* Export injectiveVarsOf{Binder,Type} from TyCoRepRyan Scott2017-10-192-29/+36
| | | | | | | | | | | | | | | | | | Summary: I ended up needing to use the functionality of `injectiveVarsOfBinder`/`injectiveVarsOfType` in this Haddock PR (https://github.com/haskell/haddock/pull/681), but alas, neither of these functions were exported. Let's do so. Test Plan: Does it compile? Reviewers: austin, goldfire, bgamari Reviewed By: bgamari Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D4107
* Fix #14369 by making injectivity warnings finer-grainedRyan Scott2017-10-191-1/+2
| | | | | | | | | | | | | | | | | | | | | Summary: Previously, GHC would always raise the possibility that a type family might not be injective in certain error messages, even if that type family actually //was// injective. Fix this by actually checking for a type family's lack of injectivity before emitting such an error message. Test Plan: ./validate Reviewers: goldfire, austin, bgamari, simonpj Reviewed By: simonpj Subscribers: simonpj, rwbarton, thomie GHC Trac Issues: #14369 Differential Revision: https://phabricator.haskell.org/D4106
* Error when deriving instances in hs-boot filesRyan Scott2017-10-191-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | Summary: According to the GHC users' guide, one cannot derive instances for data types in `.hs-boot` files. However, GHC was not enforcing this in practice, which led to #14365. Fix this by actually throwing an error if a derived instance is detected in an `.hs-boot` file (and recommend how to fix it in the error message.) Test Plan: make test TEST=T14365 Reviewers: ezyang, austin, bgamari, simonpj Reviewed By: simonpj Subscribers: simonpj, rwbarton, thomie GHC Trac Issues: #14365 Differential Revision: https://phabricator.haskell.org/D4102
* Typofix in commentGabor Greif2017-10-181-1/+1
|
* Better solving for representational equalitiesSimon Peyton Jones2017-10-184-163/+215
| | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a bit of extra solving power for representational equality constraints to fix Trac #14333 The main changes: * Fix a buglet in TcType.isInsolubleOccursCheck which wrongly reported a definite occurs-check error for (a ~R# b a) * Get rid of TcSMonad.emitInsolubles. It had an ad-hoc duplicate-removal piece that is better handled in interactIrred, now that insolubles are Irreds. We need a little care to keep inert_count (which does not include insolubles) accurate. * Refactor TcInteract.solveOneFromTheOther, to return a much simpler type. It was just over-complicated before. * Make TcInteract.interactIrred look for constraints that match either way around, in TcInteract.findMatchingIrreds This wasn't hard and it cleaned up quite a bit of code.
View Lorry Controller Status