| Commit message (Collapse) | Author | Age | Files | Lines |
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This big patch addresses the rats-nest of issues that have plagued
us for years, about the relationship between Type and Constraint.
See #11715/#21623.
The main payload of the patch is:
* To introduce CONSTRAINT :: RuntimeRep -> Type
* To make TYPE and CONSTRAINT distinct throughout the compiler
Two overview Notes in GHC.Builtin.Types.Prim
* Note [TYPE and CONSTRAINT]
* Note [Type and Constraint are not apart]
This is the main complication.
The specifics
* New primitive types (GHC.Builtin.Types.Prim)
- CONSTRAINT
- ctArrowTyCon (=>)
- tcArrowTyCon (-=>)
- ccArrowTyCon (==>)
- funTyCon FUN -- Not new
See Note [Function type constructors and FunTy]
and Note [TYPE and CONSTRAINT]
* GHC.Builtin.Types:
- New type Constraint = CONSTRAINT LiftedRep
- I also stopped nonEmptyTyCon being built-in; it only needs to be wired-in
* Exploit the fact that Type and Constraint are distinct throughout GHC
- Get rid of tcView in favour of coreView.
- Many tcXX functions become XX functions.
e.g. tcGetCastedTyVar --> getCastedTyVar
* Kill off Note [ForAllTy and typechecker equality], in (old)
GHC.Tc.Solver.Canonical. It said that typechecker-equality should ignore
the specified/inferred distinction when comparein two ForAllTys. But
that wsa only weakly supported and (worse) implies that we need a separate
typechecker equality, different from core equality. No no no.
* GHC.Core.TyCon: kill off FunTyCon in data TyCon. There was no need for it,
and anyway now we have four of them!
* GHC.Core.TyCo.Rep: add two FunTyFlags to FunCo
See Note [FunCo] in that module.
* GHC.Core.Type. Lots and lots of changes driven by adding CONSTRAINT.
The key new function is sORTKind_maybe; most other changes are built
on top of that.
See also `funTyConAppTy_maybe` and `tyConAppFun_maybe`.
* Fix a longstanding bug in GHC.Core.Type.typeKind, and Core Lint, in
kinding ForAllTys. See new tules (FORALL1) and (FORALL2) in GHC.Core.Type.
(The bug was that before (forall (cv::t1 ~# t2). blah), where
blah::TYPE IntRep, would get kind (TYPE IntRep), but it should be
(TYPE LiftedRep). See Note [Kinding rules for types] in GHC.Core.Type.
* GHC.Core.TyCo.Compare is a new module in which we do eqType and cmpType.
Of course, no tcEqType any more.
* GHC.Core.TyCo.FVs. I moved some free-var-like function into this module:
tyConsOfType, visVarsOfType, and occCheckExpand. Refactoring only.
* GHC.Builtin.Types. Compiletely re-engineer boxingDataCon_maybe to
have one for each /RuntimeRep/, rather than one for each /Type/.
This dramatically widens the range of types we can auto-box.
See Note [Boxing constructors] in GHC.Builtin.Types
The boxing types themselves are declared in library ghc-prim:GHC.Types.
GHC.Core.Make. Re-engineer the treatment of "big" tuples (mkBigCoreVarTup
etc) GHC.Core.Make, so that it auto-boxes unboxed values and (crucially)
types of kind Constraint. That allows the desugaring for arrows to work;
it gathers up free variables (including dictionaries) into tuples.
See Note [Big tuples] in GHC.Core.Make.
There is still work to do here: #22336. But things are better than
before.
* GHC.Core.Make. We need two absent-error Ids, aBSENT_ERROR_ID for types of
kind Type, and aBSENT_CONSTRAINT_ERROR_ID for vaues of kind Constraint.
Ditto noInlineId vs noInlieConstraintId in GHC.Types.Id.Make;
see Note [inlineId magic].
* GHC.Core.TyCo.Rep. Completely refactor the NthCo coercion. It is now called
SelCo, and its fields are much more descriptive than the single Int we used to
have. A great improvement. See Note [SelCo] in GHC.Core.TyCo.Rep.
* GHC.Core.RoughMap.roughMatchTyConName. Collapse TYPE and CONSTRAINT to
a single TyCon, so that the rough-map does not distinguish them.
* GHC.Core.DataCon
- Mainly just improve documentation
* Some significant renamings:
GHC.Core.Multiplicity: Many --> ManyTy (easier to grep for)
One --> OneTy
GHC.Core.TyCo.Rep TyCoBinder --> GHC.Core.Var.PiTyBinder
GHC.Core.Var TyCoVarBinder --> ForAllTyBinder
AnonArgFlag --> FunTyFlag
ArgFlag --> ForAllTyFlag
GHC.Core.TyCon TyConTyCoBinder --> TyConPiTyBinder
Many functions are renamed in consequence
e.g. isinvisibleArgFlag becomes isInvisibleForAllTyFlag, etc
* I refactored FunTyFlag (was AnonArgFlag) into a simple, flat data type
data FunTyFlag
= FTF_T_T -- (->) Type -> Type
| FTF_T_C -- (-=>) Type -> Constraint
| FTF_C_T -- (=>) Constraint -> Type
| FTF_C_C -- (==>) Constraint -> Constraint
* GHC.Tc.Errors.Ppr. Some significant refactoring in the TypeEqMisMatch case
of pprMismatchMsg.
* I made the tyConUnique field of TyCon strict, because I
saw code with lots of silly eval's. That revealed that
GHC.Settings.Constants.mAX_SUM_SIZE can only be 63, because
we pack the sum tag into a 6-bit field. (Lurking bug squashed.)
Fixes
* #21530
Updates haddock submodule slightly.
Performance changes
~~~~~~~~~~~~~~~~~~~
I was worried that compile times would get worse, but after
some careful profiling we are down to a geometric mean 0.1%
increase in allocation (in perf/compiler). That seems fine.
There is a big runtime improvement in T10359
Metric Decrease:
LargeRecord
MultiLayerModulesTH_OneShot
T13386
T13719
Metric Increase:
T8095
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Fixes #22375.
Co-authored-by: Simon Peyton Jones <simon.peytonjones@gmail.com>
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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
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See Note [Fast path for data constructors] in
GHC.Core.Opt.Simplify.Iteration
This bypasses lots of expensive logic, in the special case of
applications of data constructors. It is a surprisingly worthwhile
improvement, as you can see in the figures below.
Metrics: compile_time/bytes allocated
------------------------------------------------
CoOpt_Read(normal) -2.0%
CoOpt_Singletons(normal) -2.0%
ManyConstructors(normal) -1.3%
T10421(normal) -1.9% GOOD
T10421a(normal) -1.5%
T10858(normal) -1.6%
T11545(normal) -1.7%
T12234(optasm) -1.3%
T12425(optasm) -1.9% GOOD
T13035(normal) -1.0% GOOD
T13056(optasm) -1.8%
T13253(normal) -3.3% GOOD
T15164(normal) -1.7%
T15304(normal) -3.4%
T15630(normal) -2.8%
T16577(normal) -4.3% GOOD
T17096(normal) -1.1%
T17516(normal) -3.1%
T18282(normal) -1.9%
T18304(normal) -1.2%
T18698a(normal) -1.2% GOOD
T18698b(normal) -1.5% GOOD
T18923(normal) -1.3%
T1969(normal) -1.3% GOOD
T19695(normal) -4.4% GOOD
T21839c(normal) -2.7% GOOD
T21839r(normal) -2.7% GOOD
T4801(normal) -3.8% GOOD
T5642(normal) -3.1% GOOD
T6048(optasm) -2.5% GOOD
T9020(optasm) -2.7% GOOD
T9630(normal) -2.1% GOOD
T9961(normal) -11.7% GOOD
WWRec(normal) -1.0%
geo. mean -1.1%
minimum -11.7%
maximum +0.1%
Metric Decrease:
T10421
T12425
T13035
T13253
T16577
T18698a
T18698b
T1969
T19695
T21839c
T21839r
T4801
T5642
T6048
T9020
T9630
T9961
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The `withDeferredDiagnostics` wrapper wasn't doing anything because the
session it was modifying wasn't used in hsc_env. Therefore the fix is
simple, just push the `getSession` call into the scope of
`withDeferredDiagnostics`.
Fixes #22391
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This patch adds the wasm32 NCG.
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This patch adds the blob length field to CmmFileEmbed. The wasm32 NCG
needs to know the precise size of each data segment.
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This patch forcibly enable Cmm switch planning for wasm32, since
otherwise the switch tables we generate may exceed the br_table
maximum allowed size.
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This patch passes -Wa,--no-type-check for wasm32 when compiling
assembly. See the added note for more detailed explanation.
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This patch enables Cmm big arithmetic on wasm32, since 64-bit
arithmetic can be efficiently lowered to wasm32 opcodes.
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The driver used to pass -Wl,--no-as-needed for LLD linking. This is
actually only supported for ELF targets, and must be avoided when
linking for wasm32.
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This patch adds addToUFM_L (backed by insertLookupWithKey),
addToUniqMap_L and intersectUniqMap_C. These UniqFM/UniqMap util
functions are used by the wasm32 NCG.
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This patch adds register mapping logic for wasm32. See Note [Register
mapping on WebAssembly] in wasm32 NCG for more description.
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This patch adds the wasm32-wasi tuple support to various places in the
tree: autoconf, hadrian, ghc-boot and also the compiler. The codegen
logic will come in subsequent commits.
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Martin Erwig's FGL (Functional Graph Library) provides an "inductive"
representation of graphs. A general graph has labeled nodes and
labeled edges. The key operation on a graph is to decompose it by
removing one node, together with the edges that connect the node to
the rest of the graph. There is also an inverse composition
operation.
The decomposition and composition operations make this representation
of graphs exceptionally well suited to implement graph algorithms in
which the graph is continually changing, as alluded to in #21259.
This commit adds `GHC.Data.Graph.Inductive.Graph`, which defines the
interface, and `GHC.Data.Graph.Inductive.PatriciaTree`, which provides
an implementation. Both modules are taken from `fgl-5.7.0.3` on
Hackage, with these changes:
- Copyright and license text have been copied into the files
themselves, not stored separately.
- Some calls to `error` have been replaced with calls to `panic`.
- Conditional-compilation support for older versions of GHC,
`containers`, and `base` has been removed.
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Now Budget roughly tracks the combined width of all arguments after unarisation.
See the changes to `Note [Worker argument budgets]`.
Fixes #21737.
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See Note [Unboxing through unboxed tuples].
Fixes #22388.
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The error message for DsUselessSpecialiseForClassMethodSelector
was just wrong (a typo in some earlier work); trivial fix
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The problem here is described at some length in
Note [Boxity for bottoming functions] and
Note [Reboxed crud for bottoming calls] in GHC.Core.Opt.DmdAnal.
This patch adds a SPECIALISE pragma for indexError, which
makes it much less vulnerable to the problem described in
these Notes.
(This came up in another line of work, where a small change made
indexError do reboxing (in nofib/spectral/simple/table_sort)
that didn't happen before my change. I've opened #22404
to document the fagility.
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The Specialiser has, for some time, fires class-op RULES in the
specialiser itself: see
Note [Specialisation modulo dictionary selectors]
This MR beefs it up a bit, so that it fires /all/ RULES in the
specialiser, not just class-op rules. See
Note [Fire rules in the specialiser]
The result is a bit more specialisation; see test
simplCore/should_compile/T21851_2
This pushed me into a bit of refactoring. I made a new data types
GHC.Core.Rules.RuleEnv, which combines
- the several source of rules (local, home-package, external)
- the orphan-module dependencies
in a single record for `getRules` to consult. That drove a bunch of
follow-on refactoring, including allowing me to remove
cr_visible_orphan_mods from the CoreReader data type.
I moved some of the RuleBase/RuleEnv stuff into GHC.Core.Rule.
The reorganisation in the Simplifier improve compile times a bit
(geom mean -0.1%), but T9961 is an outlier
Metric Decrease:
T9961
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The following `TcRnDiagnostic` messages have been introduced:
TcRnWarnUnsatisfiedMinimalDefinition
TcRnMisplacedInstSig
TcRnBadBootFamInstDeclErr
TcRnIllegalFamilyInstance
TcRnAssocInClassErr
TcRnBadFamInstDecl
TcRnNotOpenFamily
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There were two bugs here:
1. Treating type-level constructors as PromotedDataCon doesn't always
work, in particular because constructors promoted via DataKinds are
called both T and 'T. (Tests T22332a, T22332b, T22315a, T22315b)
Fix: guard these cases with isDataKindsPromotedDataCon.
2. Type-level constructors were sent to the code generator, producing
things like constructor wrappers. (Tests T22332a, T22332b)
Fix: test for them in isDataTyCon.
Other changes:
* changed the marking of "type data" DataCon's as suggested by SPJ.
* added a test TDGADT for a type-level GADT.
* comment tweaks
* change tcIfaceTyCon to ignore IfaceTyConInfo, so that IfaceTyConInfo
is used only for pretty printing, not for typechecking. (SPJ)
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Also add perf test for infinite list fusion.
In particular, in `GHC.Core`, often we deal with infinite lists of roles. Also in a few locations we deal with infinite lists of names.
Thanks to simonpj for helping to write the Note [Fusion for `Infinite` lists].
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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.
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Introduces GHC.Prelude.Basic which can be used in modules which are a
dependency of the ppr code.
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Gergo points out that these bindings are tidied, rather than prepd as
the variable claims. Therefore we update the name of the variable to
reflect reality and add a comment to the data type to try to erase any
future confusion.
Fixes #22307
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Ticket #22379 revealed that skolemiseQuantifiedTyVar was
dropping the passed-in skol_info on the floor when it encountered
a SkolemTv. Bad! Several TyCons thereby share a single SkolemInfo
on their binders, which lead to bogus error reports.
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Before this patch, when converting from TH.Exp to LHsExpr GhcPs,
the compiler inserted more parentheses than required:
((f a) (b + c)) d
This was happening because the LHS of the function application was
parenthesized as if it was the RHS.
Now we use funPrec and appPrec appropriately and produce sensibly
parenthesized expressions:
f a (b + c) d
I also took the opportunity to remove the special case for LamE,
which was not special at all and simply duplicated code.
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* 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
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I had forgotten to add the auxiliary dict bindings to the
/unfolding/ of a specialised function. This caused #22358,
which reports failures when compiling Hackage packages
fixed-vector
indexed-traversable
Regression test T22357 is snarfed from indexed-traversable
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This change aims to minimize source location information leaking
into interface files, which makes ABI hashes dependent on the
build location.
The `Binary (Located a)` instance has been removed completely.
It seems that the HIE interface still needs the ability to
serialize SrcSpans, but by wrapping the instances, it should
be a lot more difficult to inadvertently add source location
information.
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When faced with VDQ in the type of a term, GHC generates the following
error message:
Illegal visible, dependent quantification in the type of a term
(GHC does not yet support this)
Prior to this patch, there were two ways this message could have been
generated and represented:
1. with the dedicated constructor TcRnVDQInTermType
(see check_type in GHC.Tc.Validity)
2. with the transitional constructor TcRnUnknownMessage
(see noNestedForallsContextsErr in GHC.Rename.Utils)
Not only this led to duplication of code generating the final SDoc,
it also made it tricky to track the origin of the error message.
This patch fixes the problem by using TcRnVDQInTermType exclusively.
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Before this patch, GHC used withHsDocContext to attach an HsDocContext
to an error message:
addErr $ mkTcRnUnknownMessage $ mkPlainError noHints (withHsDocContext ctxt msg)
The problem with this approach is that it only works with
TcRnUnknownMessage. But could we attach an HsDocContext to a
structured error message in a generic way? This patch solves
the problem by introducing a new constructor to TcRnMessage:
data TcRnMessage where
...
TcRnWithHsDocContext :: !HsDocContext -> !TcRnMessage -> TcRnMessage
...
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This patch fixes two distinct (but closely related) buglets that were uncovered
in #22235:
* `liftEnvSubst` used an empty in-scope set, which was not wide enough to cover
the variables in the range of the substitution. This patch fixes this by
populating the in-scope set from the free variables in the range of the
substitution.
* `composeTCvSubst` applied the first substitution argument to the range of the
second substitution argument, but the first substitution's in-scope set was
not wide enough to cover the range of the second substutition. We similarly
fix this issue in this patch by widening the first substitution's in-scope set
before applying it.
Fixes #22235.
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Remove unused mkPtrString and isUnderscoreFS.
We no longer use mkPtrString since 1d03d8bef96.
Remove unnecessary conversions between FastString and String and back.
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Move doCpp out of the driver to be able to use it in the upcoming JS backend.
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The comment applies only when host's word size < target's word size.
So we can relax the guard.
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ghc-bignum needs a way to raise numerical exceptions defined in base
package. At the time we used FFI calls into primops defined in the RTS.
These FFI calls had to be wrapped into hacky bottoming functions because
"foreign import prim" syntax doesn't support giving a bottoming demand
to the foreign call (cf #16929).
These hacky wrapper functions trip up the JavaScript backend (#21078)
because they are polymorphic in their return type. This commit
replaces them with primops very similar to raise# but raising predefined
exceptions.
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Ticket #13873 unexpectedly showed that a SPECIALISE pragma made a
program run (a lot) slower, because less specialisation took place
overall. It turned out that the specialiser was missing opportunities
because of quantified type variables.
It was quite easy to fix. The story is given in
Note [Specialising polymorphic dictionaries]
Two other minor fixes in the specialiser
* There is no benefit in specialising data constructor /wrappers/.
(They can appear overloaded because they are given a dictionary
to store in the constructor.) Small guard in canSpecImport.
* There was a buglet in the UnspecArg case of specHeader, in the
case where there is a dead binder. We need a LitRubbish filler
for the specUnfolding stuff. I expanded
Note [Drop dead args from specialisations] to explain.
There is a 4% increase in compile time for T15164, because we generate
more specialised code. This seems OK.
Metric Increase:
T15164
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This patch fixes #21229 properly, by avoiding doing a
binder-swap on dictionary Ids. This is pretty subtle, and explained
in Note [Care with binder-swap on dictionaries].
Test is already in simplCore/should_run/T21229
This allows us to restore a feature to the specialiser that we had
to revert: see Note [Specialising polymorphic dictionaries].
(This is done in a separate patch.)
I also modularised things, using a new function scrutBinderSwap_maybe
in all the places where we are (effectively) doing a binder-swap,
notably
* Simplify.Iteration.addAltUnfoldings
* SpecConstr.extendCaseBndrs
In Simplify.Iteration.addAltUnfoldings I also eliminated a guard
Many <- idMult case_bndr
because we concluded, in #22123, that it was doing no good.
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It now properly lints cases where sums end up distributed
over multiple args after unarise.
Fixes #22026.
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Replaces uses of `TcRnUnknownMessage` in `GHC.Tc.Gen.Splice` with
structured diagnostics.
closes #20116
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Updates the haddock submodule.
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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>
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