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PowerPC: for ccalls, use the correct minimum size (32 bytes) for the
parameter area

Merge the eval-apply-branch on to the HEAD
------------------------------------------

This is a change to GHC's evaluation model in order to ultimately make
GHC more portable and to reduce complexity in some areas.

At some point we'll update the commentary to describe the new state of
the RTS.  Pending that, the highlights of this change are:

  - No more Su.  The Su register is gone, update frames are one
    word smaller.

  - Slow-entry points and arg checks are gone.  Unknown function calls
    are handled by automatically-generated RTS entry points (AutoApply.hc,
    generated by the program in utils/genapply).

  - The stack layout is stricter: there are no "pending arguments" on
    the stack any more, the stack is always strictly a sequence of
    stack frames.

    This means that there's no need for LOOKS_LIKE_GHC_INFO() or
    LOOKS_LIKE_STATIC_CLOSURE() any more, and GHC doesn't need to know
    how to find the boundary between the text and data segments (BIG WIN!).

  - A couple of nasty hacks in the mangler caused by the neet to
    identify closure ptrs vs. info tables have gone away.

  - Info tables are a bit more complicated.  See InfoTables.h for the
    details.

  - As a side effect, GHCi can now deal with polymorphic seq.  Some bugs
    in GHCi which affected primitives and unboxed tuples are now
    fixed.

  - Binary sizes are reduced by about 7% on x86.  Performance is roughly
    similar, some programs get faster while some get slower.  I've seen
    GHCi perform worse on some examples, but haven't investigated
    further yet (GHCi performance *should* be about the same or better
    in theory).

  - Internally the code generator is rather better organised.  I've moved
    info-table generation from the NCG into the main codeGen where it is
    shared with the C back-end; info tables are now emitted as arrays
    of words in both back-ends.  The NCG is one step closer to being able
    to support profiling.

This has all been fairly thoroughly tested, but no doubt I've messed
up the commit in some way.

Repair the HEAD after some file adds/removes that were supposed to
happen on the eval-apply-branch yesterday mysteriously happened on the
HEAD instead.

Snapshot of the Eval/Apply changes, c. 15 Nov 2002.  This snapshot
should be relatively stable, although GHCi and profiling are currently
known to be broken.

Fix a type and a bug for PowerPC.

make it compile again (x86)

The Native Code Generator for PowerPC.
Still to be done:
*) Proper support of Floats and Doubles
   currently it seems to work, but it's just guesswork.
*) Some missing operations, only needed for -O, AFAICT.
*) Mach-O dynamic linker stub generation.
   (can't import foreign functions from dynamic libraries,
   and it might fail for big programs)

Native code gen primpops (courtesy Julian)

--------------------------------------
	Make Template Haskell into the HEAD
	--------------------------------------

This massive commit transfers to the HEAD all the stuff that
Simon and Tim have been doing on Template Haskell.  The
meta-haskell-branch is no more!

WARNING: make sure that you

  * Update your links if you are using link trees.
    Some modules have been added, some have gone away.

  * Do 'make clean' in all library trees.
    The interface file format has changed, and you can
    get strange panics (sadly) if GHC tries to read old interface files:
    e.g.  ghc-5.05: panic! (the `impossible' happened, GHC version 5.05):
	  Binary.get(TyClDecl): ForeignType

  * You need to recompile the rts too; Linker.c has changed


However the libraries are almost unaltered; just a tiny change in
Base, and to the exports in Prelude.


NOTE: so far as TH itself is concerned, expression splices work
fine, but declaration splices are not complete.


		---------------
		The main change
		---------------

The main structural change: renaming and typechecking have to be
interleaved, because we can't rename stuff after a declaration splice
until after we've typechecked the stuff before (and the splice
itself).

* Combine the renamer and typecheker monads into one
	(TcRnMonad, TcRnTypes)
  These two replace TcMonad and RnMonad

* Give them a single 'driver' (TcRnDriver).  This driver
  replaces TcModule.lhs and Rename.lhs

* The haskell-src library package has a module
	Language/Haskell/THSyntax
  which defines the Haskell data type seen by the TH programmer.

* New modules:
	hsSyn/Convert.hs 	converts THSyntax -> HsSyn
	deSugar/DsMeta.hs 	converts HsSyn -> THSyntax

* New module typecheck/TcSplice type-checks Template Haskell splices.

		-------------
		Linking stuff
		-------------

* ByteCodeLink has been split into
	ByteCodeLink	(which links)
	ByteCodeAsm	(which assembles)

* New module ghci/ObjLink is the object-code linker.

* compMan/CmLink is removed entirely (was out of place)
  Ditto CmTypes (which was tiny)

* Linker.c initialises the linker when it is first used (no need to call
  initLinker any more).  Template Haskell makes it harder to know when
  and whether to initialise the linker.


	-------------------------------------
	Gathering the LIE in the type checker
	-------------------------------------

* Instead of explicitly gathering constraints in the LIE
	tcExpr :: RenamedExpr -> TcM (TypecheckedExpr, LIE)
  we now dump the constraints into a mutable varabiable carried
  by the monad, so we get
	tcExpr :: RenamedExpr -> TcM TypecheckedExpr

  Much less clutter in the code, and more efficient too.
  (Originally suggested by Mark Shields.)


		-----------------
		Remove "SysNames"
		-----------------

Because the renamer and the type checker were entirely separate,
we had to carry some rather tiresome implicit binders (or "SysNames")
along inside some of the HsDecl data structures.  They were both
tiresome and fragile.

Now that the typechecker and renamer are more intimately coupled,
we can eliminate SysNames (well, mostly... default methods still
carry something similar).

		-------------
		Clean up HsPat
		-------------

One big clean up is this: instead of having two HsPat types (InPat and
OutPat), they are now combined into one.  This is more consistent with
the way that HsExpr etc is handled; there are some 'Out' constructors
for the type checker output.

So:
	HsPat.InPat	--> HsPat.Pat
	HsPat.OutPat	--> HsPat.Pat
	No 'pat' type parameter in HsExpr, HsBinds, etc

	Constructor patterns are nicer now: they use
		HsPat.HsConDetails
	for the three cases of constructor patterns:
		prefix, infix, and record-bindings

	The *same* data type HsConDetails is used in the type
	declaration of the data type (HsDecls.TyData)

Lots of associated clean-up operations here and there.  Less code.
Everything is wonderful.

Finally separate the compiler from hslibs.

Mainly import wibbles, and use the new POSIX library when
bootstrapping.

Housekeeping:

  - The main goal is to remove dependencies on hslibs for a
    bootstrapped compiler, leaving only a requirement that the
    packages base, haskell98 and readline are built in stage 1 in
    order to bootstrap.  We're almost there: Posix is still required
    for signal handling, but all other dependencies on hslibs are now
    gone.

    Uses of Addr and ByteArray/MutableByteArray array are all gone
    from the compiler.  PrimPacked defines the Ptr type for GHC 4.08
    (which didn't have it), and it defines simple BA and MBA types to
    replace uses of ByteArray and MutableByteArray respectively.

  - Clean up import lists.  HsVersions.h now defines macros for some
    modules which have moved between GHC versions.  eg. one now
    imports 'GLAEXTS' to get at unboxed types and primops in the
    compiler.

    Many import lists have been sorted as per the recommendations in
    the new style guidelines in the commentary.

I've built the compiler with GHC 4.08.2, 5.00.2, 5.02.3, 5.04 and
itself, and everything still works here.  Doubtless I've got something
wrong, though.

PrimRep Cleanup

   - Remove all PrimReps which were just different flavours of
     PtrRep.  Now, everything which is a pointer to a closure of
     some kind is always a PtrRep.

   - Three of the deleted PrimReps, namely ArrayRep, ByteArrayRep,
     and ForeignObj rep, had a subtle reason for their existence:
     the abstract C pretty-printer(!) used them to decide whether
     to apply a shim to an outgoing C-call argument: a ByteArrayRep
     argument would be adjusted to point past the object header,
     for example.

     I've changed this to happen in a much more reasonable and
     obvious way: there are now explict macros in AbsCSyn to do the
     adjustment, and the code generator makes calls to these as
     necessary.  Slightly less hackery is necessary in the NCG as
     a result.

Sparc NCG fix from Sven Panne: 8-byte align the stack ptr when doing a ccall.

Implement a primitive failsafe mechanism for protecting against
linking inconsistent object files.  The idea is that if object files
which were compiled in the wrong order (non-dependency order) or
compiled in different ways (eg. profiled vs. non-profiled) are linked
together, a link error will result.

This is achieved by adding the module version and the way to the
module init label.  For example, previously the init label for a
module Foo was named

	__stginit_Foo

now it is named

	__stginit_Foo_<version>_<way>

where <version> is the module version of Foo (same as the version in
the interface file), and <way> is the current way (or empty).

We also have to have a way to refer to the old plain init label, for
using as the argument to shutdownHaskell() in a program using foreign
exports.  So the old label now points to a jump instruction which
transfers control to the new init code.

Teach code gen about some extra no-ops

ptext => ftext

FastString cleanup, stage 1.

The FastString type is no longer a mixture of hashed strings and
literal strings, it contains hashed strings only with O(1) comparison
(except for UnicodeStr, but that will also go away in due course).  To
create a literal instance of FastString, use FSLIT("..").

By far the most common use of the old literal version of FastString
was in the pattern

	  ptext SLIT("...")

this combination still works, although it doesn't go via FastString
any more.  The next stage will be to remove the need to use this
special combination at all, using a RULE.

To convert a FastString into an SDoc, now use 'ftext' instead of
'ptext'.

I've also removed all the FAST_STRING related macros from HsVersions.h
except for SLIT and FSLIT, just use the relevant functions from
FastString instead.

Friday afternoon pet peeve removal: define (Util.notNull :: [a] -> Bool) and use it

Import wibbles

Back out previous fix, it was wrong.

Remove the interface file parser, and move .hi-boot parsing into the
main parser.  The syntax of .hi-boot files is now greatly improved in
terms of readability; here's an example:

	module M where
	data T
	f :: T -> GHC.Base.Int

note that
	(a) layout can be used
	(b) there's no explcit export list; everything declared
	    is implicitly exported
	(c) Z-encoding of names is no longer required
	(d) Any identifier not declared in the current module must
	    still be quailified with the module which originally
	    defined it (eg. GHC.Base.Int above).

We'd like to relax (d), but that will come later.

Cope with VoidRep fields in a static constructor.

Fix a bug in the native code generator's handling of floating-point
arguments to ccalls: it wasn't correctly promoting float arguments to
doubles.  Amazingly this has gone undetected for quite a while.

Fixes bug #523996.

New call attribute on foreign imports, threadsafe.

It indicates that a foreign import can(*) safely be called
concurrently with the continued evaluation of other Haskell
threads, i.e., when the foreign call is made by a Haskell
thread, it won't hinder the progress of other threads.

(*) - if the platform and RTS supports it, it _will be_
invoked concurrently.

Import wibbles

Switch over to the new hierarchical libraries
---------------------------------------------

This commit reorganises our libraries to use the new hierarchical
module namespace extension.

The basic story is this:

   - fptools/libraries contains the new hierarchical libraries.
     Everything in here is "clean", i.e. most deprecated stuff has
     been removed.

	- fptools/libraries/base is the new base package
	  (replacing "std") and contains roughly what was previously
	  in std, lang, and concurrent, minus deprecated stuff.
	  Things that are *not allowed* in libraries/base include:
		Addr, ForeignObj, ByteArray, MutableByteArray,
		_casm_, _ccall_, ``'', PrimIO

	  For ByteArrays and MutableByteArrays we use UArray and
	  STUArray/IOUArray respectively now.

	  Modules previously called PrelFoo are now under
	  fptools/libraries/GHC.  eg. PrelBase is now GHC.Base.

	- fptools/libraries/haskell98 provides the Haskell 98 std.
	  libraries (Char, IO, Numeric etc.) as a package.  This
	  package is enabled by default.

	- fptools/libraries/network is a rearranged version of
	  the existing net package (the old package net is still
	  available; see below).

	- Other packages will migrate to fptools/libraries in
	  due course.

     NB. you need to checkout fptools/libraries as well as
     fptools/hslibs now.  The nightly build scripts will need to be
     tweaked.

   - fptools/hslibs still contains (almost) the same stuff as before.
     Where libraries have moved into the new hierarchy, the hslibs
     version contains a "stub" that just re-exports the new version.
     The idea is that code will gradually migrate from fptools/hslibs
     into fptools/libraries as it gets cleaned up, and in a version or
     two we can remove the old packages altogether.

   - I've taken the opportunity to make some changes to the build
     system, ripping out the old hslibs Makefile stuff from
     mk/target.mk; the new package building Makefile code is in
     mk/package.mk (auto-included from mk/target.mk).

     The main improvement is that packages now register themselves at
     make boot time using ghc-pkg, and the monolithic package.conf
     in ghc/driver is gone.

     I've updated the standard packages but haven't tested win32,
     graphics, xlib, object-io, or OpenGL yet.  The Makefiles in
     these packages may need some further tweaks, and they'll need
     pkg.conf.in files added.

   - Unfortunately all this rearrangement meant I had to bump the
     interface-file version and create a bunch of .hi-boot-6 files :-(

Clean up the AbsC -> AbsC translation of array operations.

* MachOps MO_ReadOSBI and MO_WriteOSBI, which previously did
  array indexing, are gone.  We translate now just to plain
  memory references and explicit address computations.  This
  has the happy side effect that all MachOps now return exactly
  one result (previously it was 0 or 1), cleaning up various
  bits of code.

  As a result the Abstract C structure now contains an unneccessary
  restriction, which is that the result of a MachOp can only be
  assigned to a temporary.  This made sense when MachOps had variable
  numbers of results (0, 1 or 2, originally), but is no longer needed.
  MachOps applied to args could now be allowed to appear as
  arbitrary nodes in expression trees, but so far they are not.

* Get rid of CAddrMode constructor CMem, since it is a special case of
  CVal with a RegRelative of CIndex.

AbstractC is inconsistent and non-orthogonal.  The StixStmt + StixExpr
combination expresses a large part of what AbstractC does in a cleaner
and simpler way, IMO.

Also implement MO_32U_to_8U for sparc.  sigh.

Implement missing MachOp, MO_8U_to_32U, for sparc.  (duh!)

Fix debug build.

Fix syntax error in printing indirect calls in sparc assembly.

x86 only: remove special ccall support for calling PerformGC_wrapper
using dodgy-looking calling convention.  PerformGC_wrapper was last
seen alive in GHC 3.X, AFAIK.

sparc NCG fixes for f-i-dynamic.

Teach the NCG how to do f-i-dynamic.  Nothing unexpected.
sparc-side now needs fixing.

merge from stable branch:
  1.46.4.3  +14 -7     fptools/ghc/compiler/nativeGen/AsmCodeGen.lhs
  1.47.4.3  +2 -0      fptools/ghc/compiler/nativeGen/MachMisc.lhs

  Treat literal appearances of BaseReg in Stix trees uniformly.
  This is now taken to mean the &MainCapability.r, regardless of
  whether BaseReg is in a register (x86) or synthesised (sparc).

merge from the stable branch:

  1.70.4.2  fptools/ghc/compiler/nativeGen/StixPrim.lhs
  1.5.10.3  fptools/ghc/includes/mkNativeHdr.c

  Track recent changes to HpLim assignment in load_thread_state.

- Implement a small GC optimisation: when a static constructor has
  been determined to have no (indirect) CAF references, we set its
  static link field to a non-zero value (currently 1).  This prevents
  the garbage collector from traversing this closure and transitively
  everything it points to, and thus should speed up GC a little.

- Omit the static link field from static constructors which have no
  pointer fields (i.e. they are CONSTR_NOCAF_STATIC).

- Add the padding words and the static link field for a static
  constructor at (AbsC) code generation time, rather than in the back
  ends.  This eliminates some duplication between PprAbsC and
  AbsCStixGen.

No need for #ifdef around shift primop now.

derive Eq Cond so that an assertion in MachCode works.

wibble