| Commit message (Collapse) | Author | Age | Files | Lines |
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Summary:
This includes pretty much all the changes needed to make `Applicative`
a superclass of `Monad` finally. There's mostly reshuffling in the
interests of avoid orphans and boot files, but luckily we can resolve
all of them, pretty much. The only catch was that
Alternative/MonadPlus also had to go into Prelude to avoid this.
As a result, we must update the hsc2hs and haddock submodules.
Signed-off-by: Austin Seipp <austin@well-typed.com>
Test Plan: Build things, they might not explode horribly.
Reviewers: hvr, simonmar
Subscribers: simonmar
Differential Revision: https://phabricator.haskell.org/D13
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Authored-by: David Luposchainsky <dluposchainsky@gmail.com>
Signed-off-by: Austin Seipp <austin@well-typed.com>
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We weren't properly tracking the number of stack arguments in the
continuation of a foreign call. It happened to work when the
continuation was not a join point, but when it was a join point we
were using the wrong amount of stack fixup.
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We would like to calculate register liveness for global registers as well as
local registers, so this patch generalizes the existing infrastructure to set
the stage.
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I've switched to passing DynFlags rather than Platform, as (a) it's
simpler to not have to extract targetPlatform in so many places, and
(b) it may be useful to have DynFlags around in future.
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* origin/master: (756 commits)
don't crash if argv[0] == NULL (#7037)
-package P was loading all versions of P in GHCi (#7030)
Add a Note, copying text from #2437
improve the --help docs a bit (#7008)
Copy Data.HashTable's hashString into our Util module
Build fix
Build fixes
Parse error: suggest brackets and indentation.
Don't build the ghc DLL on Windows; works around trac #5987
On Windows, detect if DLLs have too many symbols; trac #5987
Add some more Integer rules; fixes #6111
Fix PA dfun construction with silent superclass args
Add silent superclass parameters to the vectoriser
Add silent superclass parameters (again)
Mention Generic1 in the user's guide
Make the GHC API a little more powerful.
tweak llvm version warning message
New version of the patch for #5461.
Fix Word64ToInteger conversion rule.
Implemented feature request on reconfigurable pretty-printing in GHCi (#5461)
...
Conflicts:
compiler/basicTypes/UniqSupply.lhs
compiler/cmm/CmmBuildInfoTables.hs
compiler/cmm/CmmLint.hs
compiler/cmm/CmmOpt.hs
compiler/cmm/CmmPipeline.hs
compiler/cmm/CmmStackLayout.hs
compiler/cmm/MkGraph.hs
compiler/cmm/OldPprCmm.hs
compiler/codeGen/CodeGen.lhs
compiler/codeGen/StgCmm.hs
compiler/codeGen/StgCmmBind.hs
compiler/codeGen/StgCmmLayout.hs
compiler/codeGen/StgCmmUtils.hs
compiler/main/CodeOutput.lhs
compiler/main/HscMain.hs
compiler/nativeGen/AsmCodeGen.lhs
compiler/simplStg/SimplStg.lhs
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We can now get the Platform from the DynFlags inside an SDoc, so we
no longer need to pass the Platform in.
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Conflicts:
compiler/cmm/CmmLint.hs
compiler/cmm/OldCmm.hs
compiler/codeGen/CgMonad.lhs
compiler/main/CodeOutput.lhs
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We now carry around with CmmJump statements a list of
the STG registers that are live at that jump site.
This is used by the LLVM backend so it can avoid
unnesecarily passing around dead registers, improving
perfromance. This gives us the framework to finally
fix trac #4308.
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This field was doing nothing. I think it originally appeared in a
very old incarnation of the new code generator.
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We only use it for "compiler" sources, i.e. not for libraries.
Many modules have a -fno-warn-tabs kludge for now.
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And some knock-on changes
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CmmTop -> CmmDecl
CmmPgm -> CmmGroup
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There's now a variant of the Outputable class that knows what
platform we're targetting:
class PlatformOutputable a where
pprPlatform :: Platform -> a -> SDoc
pprPlatformPrec :: Platform -> Rational -> a -> SDoc
and various instances have had to be converted to use that class,
and we pass Platform around accordingly.
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Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
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Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
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This changes the new code generator to make use of the Hoopl package
for dataflow analysis. Hoopl is a new boot package, and is maintained
in a separate upstream git repository (as usual, GHC has its own
lagging darcs mirror in http://darcs.haskell.org/packages/hoopl).
During this merge I squashed recent history into one patch. I tried
to rebase, but the history had some internal conflicts of its own
which made rebase extremely confusing, so I gave up. The history I
squashed was:
- Update new codegen to work with latest Hoopl
- Add some notes on new code gen to cmm-notes
- Enable Hoopl lag package.
- Add SPJ note to cmm-notes
- Improve GC calls on new code generator.
Work in this branch was done by:
- Milan Straka <fox@ucw.cz>
- John Dias <dias@cs.tufts.edu>
- David Terei <davidterei@gmail.com>
Edward Z. Yang <ezyang@mit.edu> merged in further changes from GHC HEAD
and fixed a few bugs.
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o Fixed bug that emitted the copy-in code for closure entry
in the wrong place -- at the initialization of the closure.
o Refactored some of the closure entry code.
o Added code to check that no LocalRegs are live-in to a procedure
-- trip up some buggy programs earlier
o Fixed environment bindings for thunks
-- we weren't (re)binding the free variables in a thunk
o Fixed a bug in proc-point splitting that dropped some updates
to the entry block in a procedure.
o Fixed improper calls to code that generates CmmLit's for strings
o New invariant on cg_loc in CgIdInfo: the expression is always tagged
o Code to load free vars on entry to a thunk was (wrongly) placed before
the heap check.
o Some of the StgCmm code was redundantly passing around Id's
along with CgIdInfo's; no more.
o Initialize the LocalReg's that point to a closure before allocating and
initializing the closure itself -- otherwise, we have problems with
recursive closure bindings
o BlockEnv and BlockSet types are now abstract.
o Update frames:
- push arguments in Old call area
- keep track of the return sp in the FCode monad
- keep the return sp in every call, tail call, and return
(because it might be different at different call sites,
e.g. tail calls to the gc after a heap check are performed
before pushing the update frame)
- set the sp appropriately on returns and tail calls
o Reduce call, tail call, and return to a single LastCall node
o Added slow entry code, using different calling conventions on entry and tail call
o More fixes to the calling convention code.
The tricky stuff is all about the closure environment: it must be passed in R1,
but in non-closures, there is no such argument, so we can't treat all arguments
the same way: the closure environment is special. Maybe the right step forward
would be to define a different calling convention for closure arguments.
o Let-no-escapes need to be emitted out-of-line -- otherwise, we drop code.
o Respect RTS requirement of word alignment for pointers
My stack allocation can pack sub-word values into a single word on the stack,
but it wasn't requiring word-alignment for pointers. It does now,
by word-aligning both pointer registers and call areas.
o CmmLint was over-aggresively ruling out non-word-aligned memory references,
which may be kosher now that we can spill small values into a single word.
o Wrong label order on a conditional branch when compiling switches.
o void args weren't dropped in many cases.
To help prevent this kind of mistake, I defined a NonVoid wrapper,
which I'm applying only to Id's for now, although there are probably
other good candidates.
o A little code refactoring: separate modules for procpoint analysis splitting,
stack layout, and building infotables.
o Stack limit check: insert along with the heap limit check, using a symbolic
constant (a special CmmLit), then replace it when the stack layout is known.
o Removed last node: MidAddToContext
o Adding block id as a literal: means that the lowering of the calling conventions
no longer has to produce labels early, which was inhibiting common-block elimination.
Will also make it easier for the non-procpoint-splitting path.
o Info tables: don't try to describe the update frame!
o Over aggressive use of NonVoid!!!!
Don't drop the non-void args before setting the type of the closure!!!
o Sanity checking:
Added a pass to stub dead dead slots on the stack
(only ~10 lines with the dataflow framework)
o More sanity checking:
Check that incoming pointer arguments are non-stubbed.
Note: these checks are still subject to dead-code removal, but they should
still be quite helpful.
o Better sanity checking: why stop at function arguments?
Instead, in mkAssign, check that _any_ assignment to a pointer type is non-null
-- the sooner the crash, the easier it is to debug.
Still need to add the debugging flag to turn these checks on explicitly.
o Fixed yet another calling convention bug.
This time, the calls to the GC were wrong. I've added a new convention
for GC calls and invoked it where appropriate.
We should really straighten out the calling convention stuff:
some of the code (and documentation) is spread across the compiler,
and there's some magical use of the node register that should really
be handled (not avoided) by calling conventions.
o Switch bug: the arms in mkCmmLitSwitch weren't returning to a single join point.
o Environment shadowing problem in Stg->Cmm:
When a closure f is bound at the top-level, we should not bind f to the
node register on entry to the closure.
Why? Because if the body of f contains a let-bound closure g that refers
to f, we want to make sure that it refers to the static closure for f.
Normally, this would all be fine, because when we compile a closure,
we rebind free variables in the environment. But f doesn't look like
a free variable because it's a static value. So, the binding for f
remains in the environment when we compile g, inconveniently referring
to the wrong thing.
Now, I bind the variable in the local environment only if the closure is not
bound at the top level. It's still okay to make assumptions about the
node holding the closure environment; we just won't find the binding
in the environment, so code that names the closure will now directly
get the label of the static closure, not the node register holding a
pointer to the static closure.
o Don't generate bogus Cmm code containing SRTs during the STG -> Cmm pass!
The tables made reference to some labels that don't exist when we compute and
generate the tables in the back end.
o Safe foreign calls need some special treatment (at least until we have the integrated
codegen). In particular:
o they need info tables
o they are not procpoints -- the successor had better be in the same procedure
o we cannot (yet) implement the calling conventions early, which means we have
to carry the calling-conv info all the way to the end
o We weren't following the old convention when registering a module.
Now, we use update frames to push any new modules that have to be registered
and enter the youngest one on the stack.
We also use the update frame machinery to specify that the return should pop
the return address off the stack.
o At each safe foreign call, an infotable must be at the bottom of the stack,
and the TSO->sp must point to it.
o More problems with void args in a direct call to a function:
We were checking the args (minus voids) to check whether the call was saturated,
which caused problems when the function really wasn't saturated because it
took an extra void argument.
o Forgot to distinguish integer != from floating != during Stg->Cmm
o Updating slotEnv and areaMap to include safe foreign calls
The dataflow analyses that produce the slotEnv and areaMap give
results for each basic block, but we also need the results for
a safe foreign call, which is a middle node.
After running the dataflow analysis, we have another pass that
updates the results to includ any safe foreign calls.
o Added a static flag for the debugging technique that inserts
instructions to stub dead slots on the stack and crashes when
a stubbed value is loaded into a pointer-typed LocalReg.
o C back end expects to see return continuations before their call sites.
Sorted the flowgraphs appropriately after splitting.
o PrimOp calling conventions are special -- unlimited registers, no stack
Yet another calling convention...
o More void value problems: if the RHS of a case arm is a void-typed variable,
don't try to return it.
o When calling some primOp, they may allocate memory; if so, we need to
do a heap check when we return from the call.
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This merge does not turn on the new codegen (which only compiles
a select few programs at this point),
but it does introduce some changes to the old code generator.
The high bits:
1. The Rep Swamp patch is finally here.
The highlight is that the representation of types at the
machine level has changed.
Consequently, this patch contains updates across several back ends.
2. The new Stg -> Cmm path is here, although it appears to have a
fair number of bugs lurking.
3. Many improvements along the CmmCPSZ path, including:
o stack layout
o some code for infotables, half of which is right and half wrong
o proc-point splitting
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o Moved BlockId stuff to a new file to avoid module recursion
o Defined stack areas for parameter-passing locations and spill slots
o Part way through replacing copy in and copy out nodes
- added movement instructions for stack pointer
- added movement instructions for call and return parameters
(but not with the proper calling conventions)
o Inserting spills and reloads for proc points is now procpoint-aware
(it was relying on the presence of a CopyIn node as a proxy for
procpoint knowledge)
o Changed ZipDataflow to expect AGraphs (instead of being polymorphic in
the type of graph)
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Several changes in this patch, partially bug fixes, partially new code:
o bug fixes in ZipDataflow
- added some checks to verify that facts converge
- removed some erroneous checks of convergence on entry nodes
- added some missing applications of transfer functions
o changed dataflow clients to use ZipDataflow, making ZipDataflow0 obsolete
o eliminated DFA monad (no need for separate analysis and rewriting monads with ZipDataflow)
o started stack layout changes
- no longer generating CopyIn and CopyOut nodes (not yet fully expunged though)
- still not using proper calling conventions
o simple new optimizations:
- common block elimination
-- have not yet tried to move the Adams opt out of CmmProcPointZ
- block concatenation
o piped optimization fuel up to the HscEnv
- can be limited by a command-line flag
- not tested, and probably not yet properly used by clients
o added unique supply to FuelMonad, also lifted unique supply to DFMonad
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C-- no longer has 'hints'; to guide parameter passing, it
has 'kinds'. Renamed type constructor, data constructor, and record
fields accordingly
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Modules that need it import it themselves instead.
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This allows the instance of UserOfLocalRegs to be within Haskell98, and IMHO
makes the code a little cleaner generally.
This is one small (though tedious) step towards making GHC's code more
portable...
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Changes too numerous to comment on, but here is some old history that
I saved:
Wed Aug 15 11:07:13 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* type synonyms made consistent with new Cmm types
M ./compiler/nativeGen/MachInstrs.hs -2 +2
Mon Aug 20 19:22:14 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* pushing return info beyond cmm into codegen
M ./compiler/codeGen/Bitmap.hs r3
M ./compiler/codeGen/CgBindery.lhs r3
M ./compiler/codeGen/CgCallConv.hs r3
M ./compiler/codeGen/CgCase.lhs r3
M ./compiler/codeGen/CgClosure.lhs r3
M ./compiler/codeGen/CgCon.lhs r3
M ./compiler/codeGen/CgExpr.lhs r3
M ./compiler/codeGen/CgForeignCall.hs -6 +7 r3
M ./compiler/codeGen/CgHeapery.lhs r3
M ./compiler/codeGen/CgHpc.hs +1 r3
M ./compiler/codeGen/CgInfoTbls.hs r3
M ./compiler/codeGen/CgLetNoEscape.lhs r3
M ./compiler/codeGen/CgMonad.lhs r3
M ./compiler/codeGen/CgParallel.hs r3
M ./compiler/codeGen/CgPrimOp.hs +3 r3
M ./compiler/codeGen/CgProf.hs r3
M ./compiler/codeGen/CgStackery.lhs r3
M ./compiler/codeGen/CgTailCall.lhs r3
M ./compiler/codeGen/CgTicky.hs r3
M ./compiler/codeGen/CgUtils.hs -1 +1 r3
M ./compiler/codeGen/ClosureInfo.lhs r3
M ./compiler/codeGen/CodeGen.lhs r3
M ./compiler/codeGen/SMRep.lhs r3
M ./compiler/nativeGen/AsmCodeGen.lhs -2 +2 r1
M ./compiler/nativeGen/MachCodeGen.hs -3 +3 r1
M ./compiler/nativeGen/MachInstrs.hs r1
M ./compiler/nativeGen/MachRegs.lhs r1
M ./compiler/nativeGen/NCGMonad.hs r1
M ./compiler/nativeGen/PositionIndependentCode.hs r1
M ./compiler/nativeGen/PprMach.hs r1
M ./compiler/nativeGen/RegAllocInfo.hs r1
M ./compiler/nativeGen/RegisterAlloc.hs r1
Mon Aug 20 20:54:41 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* put CmmReturnInfo into a CmmCall (and related types)
M ./compiler/cmm/Cmm.hs -2 +1 r3
M ./compiler/cmm/CmmBrokenBlock.hs -13 +12 r1
M ./compiler/cmm/CmmCPS.hs -3 +3
M ./compiler/cmm/CmmCPSGen.hs -8 +6 r1
M ./compiler/cmm/CmmLint.hs -1 +1
M ./compiler/cmm/CmmLive.hs -1 +1
M ./compiler/cmm/CmmOpt.hs -3 +3
M ./compiler/cmm/CmmParse.y -6 +6 r3
M ./compiler/cmm/PprC.hs -3 +3
M ./compiler/cmm/PprCmm.hs -7 +4 r2
M ./compiler/codeGen/CgForeignCall.hs -7 +6 r2
M ./compiler/codeGen/CgHpc.hs -1 r1
M ./compiler/codeGen/CgPrimOp.hs -3 r1
M ./compiler/codeGen/CgUtils.hs -1 +1 r1
M ./compiler/nativeGen/AsmCodeGen.lhs -2 +2
M ./compiler/nativeGen/MachCodeGen.hs -3 +3 r1
Tue Aug 21 18:09:13 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* add call info in nativeGen
M ./compiler/nativeGen/AsmCodeGen.lhs r1
M ./compiler/nativeGen/MachInstrs.hs r1
M ./compiler/nativeGen/MachRegs.lhs r1
M ./compiler/nativeGen/NCGMonad.hs r1
M ./compiler/nativeGen/PositionIndependentCode.hs r1
M ./compiler/nativeGen/PprMach.hs r1
M ./compiler/nativeGen/RegAllocInfo.hs r1
Wed Aug 22 16:41:58 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* ListGraph is now a newtype, not a synonym
The resultant bookkeepping is unenviable, but the change
greatly simplifies our ability to make Cmm things propertly
Outputable for both list-graph and zipper-graph representations.
M ./compiler/cmm/Cmm.hs -5 +3
M ./compiler/cmm/CmmCPS.hs -2 +2
M ./compiler/cmm/CmmCPSGen.hs -1 +1
M ./compiler/cmm/CmmContFlowOpt.hs -3 +3
M ./compiler/cmm/CmmCvt.hs -2 +2
M ./compiler/cmm/CmmInfo.hs -2 +3
M ./compiler/cmm/CmmLint.hs -1 +1
M ./compiler/cmm/CmmOpt.hs -2 +2
M ./compiler/cmm/PprC.hs -1 +1
M ./compiler/cmm/PprCmm.hs -5 +8
M ./compiler/cmm/PprCmmZ.hs -7 +1
M ./compiler/codeGen/CgMonad.lhs -1 +1
M ./compiler/nativeGen/AsmCodeGen.lhs -15 +15
M ./compiler/nativeGen/MachCodeGen.hs -2 +2
M ./compiler/nativeGen/PositionIndependentCode.hs -6 +6
M ./compiler/nativeGen/PprMach.hs -3 +2
M ./compiler/nativeGen/RegAllocColor.hs +1
M ./compiler/nativeGen/RegAllocLinear.hs -4 +5
M ./compiler/nativeGen/RegCoalesce.hs -6 +6
M ./compiler/nativeGen/RegLiveness.hs -12 +12
Thu Aug 23 13:44:49 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* diagnostic assistance in case fromJust fails
M ./compiler/nativeGen/MachCodeGen.hs -2 +5
Thu Aug 23 14:07:28 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* give every block, even the first, a label
With branch-chain elimination, the first block of a procedure
might be the target of a branch. This actually happens to
a dozen or more procedures in the run-time system.
M ./compiler/nativeGen/PprMach.hs -8 +3
Fri Aug 24 17:27:04 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* clean up the code in PprMach
M ./compiler/nativeGen/PprMach.hs -16 +14
Fri Aug 24 19:35:03 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* a bunch of impedance matching to get the compiler to build, plus
* the plus is diagnostics for unreachable code, which required
moving a lot of prettyprinting code
M ./compiler/cmm/Cmm.hs -7 +5
M ./compiler/cmm/CmmCPSZ.hs -1 +1
M ./compiler/cmm/CmmCvt.hs -8 +8
M ./compiler/cmm/CmmParse.y -4 +3
M ./compiler/cmm/MkZipCfg.hs -19 +9
M ./compiler/cmm/PprCmmZ.hs -118 +4
M ./compiler/cmm/ZipCfg.hs -1 +13
M ./compiler/cmm/ZipCfgCmm.hs -10 +129
M ./compiler/main/HscMain.lhs -4 +4
M ./compiler/nativeGen/NCGMonad.hs -2 +2
M ./compiler/nativeGen/RegAllocInfo.hs -3 +3
Fri Aug 31 14:38:02 BST 2007 Norman Ramsey <nr@eecs.harvard.edu>
* fix a warning about an import
M ./compiler/nativeGen/RegAllocColor.hs -1 +1
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The type parameter to a C-- procedure now represents a control-flow
graph, not a single instruction. The newtype ListGraph preserves the
current representation while enabling other representations and a
sensible way of prettyprinting. Except for a few changes in the
prettyprinter the new compiler binary should be bit-for-bit identical
to the old.
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Older GHCs can't parse OPTIONS_GHC.
This also changes the URL referenced for the -w options from
WorkingConventions#Warnings to CodingStyle#Warnings for the compiler
modules.
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This patch implements pointer tagging as per our ICFP'07 paper "Faster
laziness using dynamic pointer tagging". It improves performance by
10-15% for most workloads, including GHC itself.
The original patches were by Alexey Rodriguez Yakushev
<mrchebas@gmail.com>, with additions and improvements by me. I've
re-recorded the development as a single patch.
The basic idea is this: we use the low 2 bits of a pointer to a heap
object (3 bits on a 64-bit architecture) to encode some information
about the object pointed to. For a constructor, we encode the "tag"
of the constructor (e.g. True vs. False), for a function closure its
arity. This enables some decisions to be made without dereferencing
the pointer, which speeds up some common operations. In particular it
enables us to avoid costly indirect jumps in many cases.
More information in the commentary:
http://hackage.haskell.org/trac/ghc/wiki/Commentary/Rts/HaskellExecution/PointerTagging
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