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* Properly cast values when writing/reading unboxed sums.Andreas Klebinger2022-11-301-1/+2
| | | | | | | Unboxed sums might store a Int8# value as Int64#. This patch makes sure we keep track of the actual value type. See Note [Casting slot arguments] for the details.
* Use a more efficient printer for code generation (#21853)Krzysztof Gogolewski2022-11-111-29/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The changes in `GHC.Utils.Outputable` are the bulk of the patch and drive the rest. The types `HLine` and `HDoc` in Outputable can be used instead of `SDoc` and support printing directly to a handle with `bPutHDoc`. See Note [SDoc versus HDoc] and Note [HLine versus HDoc]. The classes `IsLine` and `IsDoc` are used to make the existing code polymorphic over `HLine`/`HDoc` and `SDoc`. This is done for X86, PPC, AArch64, DWARF and dependencies (printing module names, labels etc.). Co-authored-by: Alexis King <lexi.lambda@gmail.com> Metric Decrease: CoOpt_Read ManyAlternatives ManyConstructors T10421 T12425 T12707 T13035 T13056 T13253 T13379 T18140 T18282 T18698a T18698b T1969 T20049 T21839c T21839r T3064 T3294 T4801 T5321FD T5321Fun T5631 T6048 T783 T9198 T9233
* Fix Cmm symbol kindCheng Shao2022-11-111-3/+6
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* Minor refactor around FastStringsKrzysztof Gogolewski2022-11-051-11/+11
| | | | | | | Pass FastStrings to functions directly, to make sure the rule for fsLit "literal" fires. Remove SDoc indirection in GHCi.UI.Tags and GHC.Unit.Module.Graph.
* Minor SDoc-related cleanupKrzysztof Gogolewski2022-10-281-10/+25
| | | | | | | | | | | * Rename pprCLabel to pprCLabelStyle, and use the name pprCLabel for a function using CStyle (analogous to pprAsmLabel) * Move LabelStyle to the CLabel module, it no longer needs to be in Outputable. * Move calls to 'text' right next to literals, to make sure the text/str rule is triggered. * Remove FastString/String roundtrip in Tc.Deriv.Generate * Introduce showSDocForUser', which abstracts over a pattern in GHCi.UI
* Introduce a standard thunk for allocating stringsÖmer Sinan Ağacan2022-10-221-1/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently for a top-level closure in the form hey = unpackCString# x we generate code like this: Main.hey_entry() // [R1] { info_tbls: [(c2T4, label: Main.hey_info rep: HeapRep static { Thunk } srt: Nothing)] stack_info: arg_space: 8 updfr_space: Just 8 } {offset c2T4: // global _rqm::P64 = R1; if ((Sp + 8) - 24 < SpLim) (likely: False) goto c2T5; else goto c2T6; c2T5: // global R1 = _rqm::P64; call (stg_gc_enter_1)(R1) args: 8, res: 0, upd: 8; c2T6: // global (_c2T1::I64) = call "ccall" arg hints: [PtrHint, PtrHint] result hints: [PtrHint] newCAF(BaseReg, _rqm::P64); if (_c2T1::I64 == 0) goto c2T3; else goto c2T2; c2T3: // global call (I64[_rqm::P64])() args: 8, res: 0, upd: 8; c2T2: // global I64[Sp - 16] = stg_bh_upd_frame_info; I64[Sp - 8] = _c2T1::I64; R2 = hey1_r2Gg_bytes; Sp = Sp - 16; call GHC.CString.unpackCString#_info(R2) args: 24, res: 0, upd: 24; } } This code is generated for every string literal. Only difference between top-level closures like this is the argument for the bytes of the string (hey1_r2Gg_bytes in the code above). With this patch we introduce a standard thunk in the RTS, called stg_MK_STRING_info, that does what `unpackCString# x` does, except it gets the bytes address from the payload. Using this, for the closure above, we generate this: Main.hey_closure" { Main.hey_closure: const stg_MK_STRING_info; const 0; // padding for indirectee const 0; // static link const 0; // saved info const hey1_r1Gg_bytes; // the payload } This is much smaller in code. Metric Decrease: T10421 T11195 T12150 T12425 T16577 T18282 T18698a T18698b Co-Authored By: Ben Gamari <ben@well-typed.com>
* Refactor IPE initializationBen Gamari2022-10-111-2/+6
| | | | | | | | | | | | | | | Here we refactor the representation of info table provenance information in object code to significantly reduce its size and link-time impact. Specifically, we deduplicate strings and represent them as 32-bit offsets into a common string table. In addition, we rework the registration logic to eliminate allocation from the registration path, which is run from a static initializer where things like allocation are technically undefined behavior (although it did previously seem to work). For similar reasons we eliminate lock usage from registration path, instead relying on atomic CAS. Closes #22077.
* CLabel: fix isInfoTableLabelCheng Shao2022-10-111-0/+7
| | | | isInfoTableLabel does not take Cmm info table into account. This patch is required for data section layout of wasm32 NCG to work.
* Minor refactor around OutputableKrzysztof Gogolewski2022-09-221-4/+4
| | | | | | | * Replace 'text . show' and 'ppr' with 'int'. * Remove Outputable.hs-boot, no longer needed * Use pprWithCommas * Factor out instructions in AArch64 codegen
* Clean up some. In particular:M Farkas-Dyck2022-09-171-12/+13
| | | | | | | | | | • Delete some dead code, largely under `GHC.Utils`. • Clean up a few definitions in `GHC.Utils.(Misc, Monad)`. • Clean up `GHC.Types.SrcLoc`. • Derive stock `Functor, Foldable, Traversable` for more types. • Derive more instances for newtypes. Bump haddock submodule.
* Fix typosEric Lindblad2022-09-141-2/+2
| | | | | | | This fixes various typos and spelling mistakes in the compiler. Fixes #21891
* Remove label style from printing contextKrzysztof Gogolewski2022-08-261-5/+8
| | | | | | | | | | | | Previously, the SDocContext used for code generation contained information whether the labels should use Asm or C style. However, at every individual call site, this is known statically. This removes the parameter to 'PprCode' and replaces every 'pdoc' used to print a label in code style with 'pprCLabel' or 'pprAsmLabel'. The OutputableP instance is now used only for dumps. The output of T15155 changes, it now uses the Asm style (which is faithful to what actually happens).
* Cleanups around pretty-printingKrzysztof Gogolewski2022-08-091-10/+7
| | | | | | | | | | * Remove hack when printing OccNames. No longer needed since e3dcc0d5 * Remove unused `pprCmms` and `instance Outputable Instr` * Simplify `pprCLabel` (no need to pass platform) * Remove evil `Show`/`Eq` instances for `SDoc`. They were needed by ImmLit, but that can take just a String instead. * Remove instance `Outputable CLabel` - proper output of labels needs a platform, and is done by the `OutputableP` instance
* cmm: Eliminate orphan Outputable instancesBen Gamari2022-07-161-0/+3
| | | | | | | Here we reorganize `GHC.Cmm` to eliminate the orphan `Outputable` and `OutputableP` instances for the Cmm AST. This makes it significantly easier to use the Cmm pretty-printers in tracing output without incurring module import cycles.
* Refactor handling of global initializersBen Gamari2022-04-011-2/+58
| | | | | | | | | | | | | | | | | | | | | | | | | | | GHC uses global initializers for a number of things including cost-center registration, info-table provenance registration, and setup of foreign exports. Previously, the global initializer arrays which referenced these initializers would live in the object file of the C stub, which would then be merged into the main object file of the module. Unfortunately, this approach is no longer tenable with the move to Clang/LLVM on Windows (see #21019). Specifically, lld's PE backend does not support object merging (that is, the -r flag). Instead we are now rather packaging a module's object files into a static library. However, this is problematic in the case of initializers as there are no references to the C stub object in the archive, meaning that the linker may drop the object from the final link. This patch refactors our handling of global initializers to instead place initializer arrays within the object file of the module to which they belong. We do this by introducing a Cmm data declaration containing the initializer array in the module's Cmm stream. While the initializer functions themselves remain in separate C stub objects, the reference from the module's object ensures that they are not dropped from the final link. In service of #21068.
* Avoid redundant imports of GHC.Driver.SessionSylvain Henry2022-03-231-1/+0
| | | | | | Remove GHC.Driver.Session imports that weren't considered as redundant because of the reexport of PlatformConstants. Also remove this reexport as modules using this datatype should import GHC.Platform instead.
* CLabel cleanup:Andreas Klebinger2022-02-281-12/+4
| | | | | | | | Remove these smart constructors for these reasons: * mkLocalClosureTableLabel : Does the same as the non-local variant. * mkLocalClosureLabel : Does the same as the non-local variant. * mkLocalInfoTableLabel : Decide if we make a local label based on the name and just use mkInfoTableLabel everywhere.
* Tag inference work.Andreas Klebinger2022-02-121-7/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This does three major things: * Enforce the invariant that all strict fields must contain tagged pointers. * Try to predict the tag on bindings in order to omit tag checks. * Allows functions to pass arguments unlifted (call-by-value). The former is "simply" achieved by wrapping any constructor allocations with a case which will evaluate the respective strict bindings. The prediction is done by a new data flow analysis based on the STG representation of a program. This also helps us to avoid generating redudant cases for the above invariant. StrictWorkers are created by W/W directly and SpecConstr indirectly. See the Note [Strict Worker Ids] Other minor changes: * Add StgUtil module containing a few functions needed by, but not specific to the tag analysis. ------------------------- Metric Decrease: T12545 T18698b T18140 T18923 LargeRecord Metric Increase: LargeRecord ManyAlternatives ManyConstructors T10421 T12425 T12707 T13035 T13056 T13253 T13253-spj T13379 T15164 T18282 T18304 T18698a T1969 T20049 T3294 T4801 T5321FD T5321Fun T783 T9233 T9675 T9961 T19695 WWRec -------------------------
* Fix a few Note inconsistenciesBen Gamari2022-02-011-5/+3
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* Consistently upper-case "Note ["Ben Gamari2022-02-011-1/+1
| | | | | | This was achieved with git ls-tree --name-only HEAD -r | xargs sed -i -e 's/note \[/Note \[/g'
* Cmm: DynFlags to CmmConfig refactordoyougnu2021-12-221-15/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add files GHC.Cmm.Config, GHC.Driver.Config.Cmm Cmm: DynFlag references --> CmmConfig Cmm.Pipeline: reorder imports, add handshake Cmm: DynFlag references --> CmmConfig Cmm.Pipeline: DynFlag references --> CmmConfig Cmm.LayoutStack: DynFlag references -> CmmConfig Cmm.Info.Build: DynFlag references -> CmmConfig Cmm.Config: use profile to retrieve platform Cmm.CLabel: unpack NCGConfig in labelDynamic Cmm.Config: reduce CmmConfig surface area Cmm.Config: add cmmDoCmmSwitchPlans field Cmm.Config: correct cmmDoCmmSwitchPlans flag The original implementation dispatches work in cmmImplementSwitchPlans in an `otherwise` branch, hence we must add a not to correctly dispatch Cmm.Config: add cmmSplitProcPoints simplify Config remove cmmBackend, and cmmPosInd Cmm.CmmToAsm: move ncgLabelDynamic to CmmToAsm Cmm.CLabel: remove cmmLabelDynamic function Cmm.Config: rename cmmOptDoLinting -> cmmDoLinting testsuite: update CountDepsAst CountDepsParser
* codeGen: Introduce flag to bounds-check array accessesBen Gamari2021-12-211-1/+3
| | | | | | | Here we introduce code generator support for instrument array primops with bounds checking, enabled with the `-fcheck-prim-bounds` flag. Introduced to debug #20769.
* Require all dirty_MUT_VAR callers to do explicit stg_MUT_VAR_CLEAN_info ↵nineonine2021-12-021-1/+4
| | | | comparison (#20088)
* Move `/includes` to `/rts/include`, sort per package betterJohn Ericson2021-08-091-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | In order to make the packages in this repo "reinstallable", we need to associate source code with a specific packages. Having a top level `/includes` dir that mixes concerns (which packages' includes?) gets in the way of this. To start, I have moved everything to `rts/`, which is mostly correct. There are a few things however that really don't belong in the rts (like the generated constants haskell type, `CodeGen.Platform.h`). Those needed to be manually adjusted. Things of note: - No symlinking for sake of windows, so we hard-link at configure time. - `CodeGen.Platform.h` no longer as `.hs` extension (in addition to being moved to `compiler/`) so as not to confuse anyone, since it is next to Haskell files. - Blanket `-Iincludes` is gone in both build systems, include paths now more strictly respect per-package dependencies. - `deriveConstants` has been taught to not require a `--target-os` flag when generating the platform-agnostic Haskell type. Make takes advantage of this, but Hadrian has yet to.
* Adds AArch64 Native Code GeneratorMoritz Angermann2021-06-051-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In which we add a new code generator to the Glasgow Haskell Compiler. This codegen supports ELF and Mach-O targets, thus covering Linux, macOS, and BSDs in principle. It was tested only on macOS and Linux. The NCG follows a similar structure as the other native code generators we already have, and should therfore be realtively easy to follow. It supports most of the features required for a proper native code generator, but does not claim to be perfect or fully optimised. There are still opportunities for optimisations. Metric Decrease: ManyAlternatives ManyConstructors MultiLayerModules PmSeriesG PmSeriesS PmSeriesT PmSeriesV T10421 T10421a T10858 T11195 T11276 T11303b T11374 T11822 T12227 T12545 T12707 T13035 T13253 T13253-spj T13379 T13701 T13719 T14683 T14697 T15164 T15630 T16577 T17096 T17516 T17836 T17836b T17977 T17977b T18140 T18282 T18304 T18478 T18698a T18698b T18923 T1969 T3064 T5030 T5321FD T5321Fun T5631 T5642 T5837 T783 T9198 T9233 T9630 T9872d T9961 WWRec Metric Increase: T4801
* Remove useless {-# LANGUAGE CPP #-} pragmasSylvain Henry2021-05-121-1/+0
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* Fully remove HsVersions.hSylvain Henry2021-05-121-2/+0
| | | | | | | | | | Replace uses of WARN macro with calls to: warnPprTrace :: Bool -> SDoc -> a -> a Remove the now unused HsVersions.h Bump haddock submodule
* Replace CPP assertions with Haskell functionsSylvain Henry2021-05-121-4/+5
| | | | | | | | | | | | | | | There is no reason to use CPP. __LINE__ and __FILE__ macros are now better replaced with GHC's CallStack. As a bonus, assert error messages now contain more information (function name, column). Here is the mapping table (HasCallStack omitted): * ASSERT: assert :: Bool -> a -> a * MASSERT: massert :: Bool -> m () * ASSERTM: assertM :: m Bool -> m () * ASSERT2: assertPpr :: Bool -> SDoc -> a -> a * MASSERT2: massertPpr :: Bool -> SDoc -> m () * ASSERTM2: assertPprM :: m Bool -> SDoc -> m ()
* 19486 Nearly all uses of `uniqCompareFS` are dubious and lack a ↵Sasha Bogicevic2021-05-061-1/+3
| | | | non-determinism justification
* Replace (ptext .. sLit) with `text`Sylvain Henry2021-04-291-26/+26
| | | | | | | | | | | | | | | 1. `text` is as efficient as `ptext . sLit` thanks to the rewrite rules 2. `text` is visually nicer than `ptext . sLit` 3. `ptext . sLit` encourages using one `ptext` for several `sLit` as in: ptext $ case xy of ... -> sLit ... ... -> sLit ... which may allocate SDoc's TextBeside constructors at runtime instead of sharing them into CAFs.
* Enhance pretty-printing perfSylvain Henry2021-04-101-11/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A few refactorings made after looking at Core/STG * Use Doc instead of SDoc in pprASCII to avoid passing the SDocContext that is never used. * Inline every SDoc wrappers in GHC.Utils.Outputable to expose Doc constructs * Add text/[] rule for empty strings (i.e., text "") * Use a single occurrence of pprGNUSectionHeader * Use bangs on Platform parameters and some others Metric Decrease: ManyAlternatives ManyConstructors T12707 T13035 T13379 T18698a T18698b T1969 T3294 T4801 T5321FD T783
* Add option to give each usage of a data constructor its own info tableMatthew Pickering2021-03-031-15/+55
| | | | | | | | | | | | | The `-fdistinct-constructor-tables` flag will generate a fresh info table for the usage of any data constructor. This is useful for debugging as now by inspecting the info table, you can determine which usage of a constructor caused that allocation rather than the old situation where the info table always mapped to the definition site of the data constructor which is useless. In conjunction with `-hi` and `-finfo-table-map` this gives a more fine grained understanding of where constructor allocations arise from in a program.
* Add -finfo-table-map which maps info tables to source positionsMatthew Pickering2021-03-031-3/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This new flag embeds a lookup table from the address of an info table to information about that info table. The main interface for consulting the map is the `lookupIPE` C function > InfoProvEnt * lookupIPE(StgInfoTable *info) The `InfoProvEnt` has the following structure: > typedef struct InfoProv_{ > char * table_name; > char * closure_desc; > char * ty_desc; > char * label; > char * module; > char * srcloc; > } InfoProv; > > typedef struct InfoProvEnt_ { > StgInfoTable * info; > InfoProv prov; > struct InfoProvEnt_ *link; > } InfoProvEnt; The source positions are approximated in a similar way to the source positions for DWARF debugging information. They are only approximate but in our experience provide a good enough hint about where the problem might be. It is therefore recommended to use this flag in conjunction with `-g<n>` for more accurate locations. The lookup table is also emitted into the eventlog when it is available as it is intended to be used with the `-hi` profiling mode. Using this flag will significantly increase the size of the resulting object file but only by a factor of 2-3x in our experience.
* Fix typosBrian Wignall2021-02-061-1/+1
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* nativeGen/dwarf: Fix procedure end addressesBen Gamari2020-11-151-0/+5
| | | | | | | | | | | | Previously the `.debug_aranges` and `.debug_info` (DIE) DWARF information would claim that procedures (represented with a `DW_TAG_subprogram` DIE) would only span the range covered by their entry block. This omitted all of the continuation blocks (represented by `DW_TAG_lexical_block` DIEs), confusing `perf`. Fix this by introducing a end-of-procedure label and using this as the `DW_AT_high_pc` of procedure `DW_TAG_subprogram` DIEs Fixes #17605.
* codeGen: Produce local symbols for module-internal functionsBen Gamari2020-11-111-0/+34
| | | | | | | | | | | | | | | | | | | | It turns out that some important native debugging/profiling tools (e.g. perf) rely only on symbol tables for function name resolution (as opposed to using DWARF DIEs). However, previously GHC would emit temporary symbols (e.g. `.La42b`) to identify module-internal entities. Such symbols are dropped during linking and therefore not visible to runtime tools (in addition to having rather un-helpful unique names). For instance, `perf report` would often end up attributing all cost to the libc `frame_dummy` symbol since Haskell code was no covered by any proper symbol (see #17605). We now rather follow the model of C compilers and emit descriptively-named local symbols for module internal things. Since this will increase object file size this behavior can be disabled with the `-fno-expose-internal-symbols` flag. With this `perf record` can finally be used against Haskell executables. Even more, with `-g3` `perf annotate` provides inline source code.
* Move this_module into NCGConfigBen Gamari2020-11-111-2/+3
| | | | | | In various places in the NCG we need the Module currently being compiled. Let's move this into the environment instead of chewing threw another register.
* Lint the compiler for extraneous LANGUAGE pragmasHécate2020-10-101-3/+3
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* Use UnitId in the backend instead of UnitSylvain Henry2020-10-091-6/+6
| | | | | | In Cmm we can only have real units identified with an UnitId. Other units (on-the-fly instantiated units and holes) are only used in type-checking backpack sessions that don't produce Cmm.
* Don't import GHC.Unit to reduce the number of dependenciesSylvain Henry2020-10-011-1/+1
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* Refactor CLabel pretty-printingSylvain Henry2020-09-231-192/+167
| | | | | | | | | | * Don't depend on the selected backend to know if we print Asm or C labels: we already have PprStyle to determine this. Moreover even when a native backend is used (NCG, LLVM) we may want to C headers containing pretty-printed labels, so it wasn't a good predicate anyway. * Make pretty-printing code clearer and avoid partiality
* Generalize OutputablePSylvain Henry2020-09-171-1/+4
| | | | | Add a type parameter for the environment required by OutputableP. It avoids tying Platform with OutputableP.
* Introduce OutputablePSylvain Henry2020-09-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | Some types need a Platform value to be pretty-printed: CLabel, Cmm types, instructions, etc. Before this patch they had an Outputable instance and the Platform value was obtained via sdocWithDynFlags. It meant that the *renderer* of the SDoc was responsible of passing the appropriate Platform value (e.g. via the DynFlags given to showSDoc). It put the burden of passing the Platform value on the renderer while the generator of the SDoc knows the Platform it is generating the SDoc for and there is no point passing a different Platform at rendering time. With this patch, we introduce a new OutputableP class: class OutputableP a where pdoc :: Platform -> a -> SDoc With this class we still have some polymorphism as we have with `ppr` (i.e. we can use `pdoc` on a variety of types instead of having a dedicated `pprXXX` function for each XXX type). One step closer removing `sdocWithDynFlags` (#10143) and supporting several platforms (#14335).
* Don't rely on CLabel's Outputable instance in CmmToCSylvain Henry2020-09-041-11/+12
| | | | | This is in preparation of the removal of sdocWithDynFlags (#10143), hence of the refactoring of CLabel's Outputable instance.
* Remove "Ord FastString" instanceSylvain Henry2020-09-011-10/+8
| | | | | | | | | | | | | | | | | | | FastStrings can be compared in 2 ways: by Unique or lexically. We don't want to bless one particular way with an "Ord" instance because it leads to bugs (#18562) or to suboptimal code (e.g. using lexical comparison while a Unique comparison would suffice). UTF-8 encoding has the advantage that sorting strings by their encoded bytes also sorts them by their Unicode code points, without having to decode the actual code points. BUT GHC uses Modified UTF-8 which diverges from UTF-8 by encoding \0 as 0xC080 instead of 0x00 (to avoid null bytes in the middle of a String so that the string can still be null-terminated). This patch adds a new `utf8CompareShortByteString` function that performs sorting by bytes but that also takes Modified UTF-8 into account. It is much more performant than decoding the strings into [Char] to perform comparisons (which we did in the previous patch). Bump haddock submodule
* DynFlags: disentangle OutputableSylvain Henry2020-08-121-0/+1
| | | | | | | | | - put panic related functions into GHC.Utils.Panic - put trace related functions using DynFlags in GHC.Driver.Ppr One step closer making Outputable fully independent of DynFlags. Bump haddock submodule
* Refactor CLabel pretty-printingSylvain Henry2020-07-311-105/+125
| | | | | | | | Pretty-printing CLabel relies on sdocWithDynFlags that we want to remove (#10143, #17957). It uses it to query the backend and the platform. This patch exposes Clabel ppr functions specialised for each backend so that backend code can directly use them.
* Remove platform constant wrappersSylvain Henry2020-07-251-12/+12
| | | | | | | | | | Platform constant wrappers took a DynFlags parameter, hence implicitly used the target platform constants. We removed them to allow support for several platforms at once (#14335) and to avoid having to pass the full DynFlags to every function (#17957). Metric Decrease: T4801
* Replace HscTarget with BackendSylvain Henry2020-07-221-1/+2
| | | | | | | | | They both have the same role and Backend name is more explicit. Metric Decrease: T3064 Update Haddock submodule
* Replace ghcWithNativeCodeGen with a proper Backend datatypeSylvain Henry2020-07-221-1/+1
| | | | | | | | | | | | | | | | * Represent backends with a `Backend` datatype in GHC.Driver.Backend * Don't detect the default backend to use for the target platform at compile time in Hadrian/make but at runtime. It makes "Settings" simpler and it is a step toward making GHC multi-target. * The latter change also fixes hadrian which has not been updated to take into account that the NCG now supports AIX and PPC64 (cf df26b95559fd467abc0a3a4151127c95cb5011b9 and d3c1dda60d0ec07fc7f593bfd83ec9457dfa7984) * Also we don't treat iOS specifically anymore (cf cb4878ffd18a3c70f98bdbb413cd3c4d1f054e1f)