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[smlnj] Diff of /sml/trunk/HISTORY

[smlnj] / sml / trunk / HISTORY

Diff of /sml/trunk/HISTORY

-revision 580, Wed Mar 22 06:33:52 2000 UTC
+revision 1040, Mon Jan 28 16:55:24 2002 UTC
 Line 8
  The form of an entry should be:
  Name:
- Date:
+ Date: yyyy/mm/dd
  Tag: <post-commit CVS tag>
  Description:
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/28 12:00:00
+ Tag: Release_110_38
+ Description:
+ This time for real!!!
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/28 10:56:00 EST
+ Tag: blume-20020128-retraction
+ Description:
+. Retracted earlier 110.38.  (The Release_110_38 tag has been replaced
+    with blume-Release_110_38-retracted.)
+. Fixed a problem with incorrect rounding modes in real64.sml.
+    (Thanks to Andrew Mccreight <andrew.mccreight@yale.edu>.)
+. A bug in ml-nlffigen related to the handling of unnamed structs, unions,
+    and enums fixed.  The naming of corresponding ML identifiers should
+    now be consistent again.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/01/27
+ Tag: leunga-20020127-nowhere
+ Description:
+    Added a target called nowhere in the configuration scripts.
+    Enabling this will build the MLRISC 'nowhere' tool (for translating
+    programs with where-clauses into legal SML code) during installation.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/25 21:27:00 EST
+ Tag: blume-Release_110_38-retracted
+ Description:
+ Call it a (working) release!  Version is 110.38. Bootfiles are ready.
+ README will be added later.
+ !!! NOTE:  Re-tagged as blume-Release_110_38-retracted. Original tag
+ (Release_110_38) removed.  Reason: Last-minute bug fixes.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/25
+ Tag: blume-20020125-ffi
+ Description:
+ A large number of tweaks and improvements to ml-nlffi-lib and
+ ml-nlffigen:
+    - ML represenation types have been streamlined
+    - getter and setter functions work with concrete values, not abstract
+      ones where possible
+    - ml-nlffigen command line more flexible (see README file there)
+    - some bugs have been fixed (hopefully)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/01/24
+ Tag: george-20020124-risc-ra-interface
+ Description:
+    There is a dramatic simplification in the interface to the
+    register allocator for RISC architectures as a result of making
+    parallel copy instructions explicit.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/22
+ Tag: blume-20020122-x86-ccalls
+ Description:
+ Bug fix for c-calls on x86 (having to do with how char- and
+ short-arguments are being handled).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/21
+ Tag: blume-20020121-ff
+ Description:
+ Another day of fiddling with the FFI...
+. Bug fix/workaround:  CKIT does not complain about negative array
+    dimensions, so ml-nlffigen has to guard itself against this possibility.
+    (Otherwise a negative dimension would send it into an infinite loop.)
+. Some of the abstract types (light objects, light pointers, most "base"
+    types) in structure C are now eqtypes.
+. Added constructors and test functions for NULL function pointers.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/18
+ Tag: blume-20020118-ready-for-new-release
+ Description:
+ Made config/srcarchiveurl point to a new place.  (Will provide boot
+ files shortly.)
+ Maybe we christen this to be 110.38?
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/18
+ Tag: blume-20020118-more-ffifiddle
+ Description:
+ Today's FFI fiddling:
+   - Provided a structure CGetSet with "convenient" versions of C.Get.* and
+     C.Set.* that use concrete (MLRep.*) arguments and results instead
+     of abstract ones.
+   - Provided word-style bit operations etc. for "int" representation
+     types in MLRep.S<Foo>Bitops where <Foo> ranges over Char, Int, Short,
+     and Long.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/18
+ Tag: blume-20020118-use-x86-fp
+ Description:
+ Now that x86-fast-fp seems to be working, I turned it back on again
+ by default.  (Seems to work fine now, even with the FFI.)
+ Other than that, I added some documentation about the FFI to
+ src/ml-nlffigen/README and updated the FFI test examples in
+ src/ml-nlffi-lib/Tests/*.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/01/17
+ Tag: leunga-20020117-x86-fast-fp-call
+ Description:
+. Fixed a problem with handling return fp values when x86's fast fp
+       mode is turned on.
+. Minor pretty printing fix for cellset.  Print %st(0) as %st(0) instead
+       of %f32.
+. Added a constructor INT32lit to the ast of MLRISC tools.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/16
+ Tag: blume-20020116-ffifiddle
+ Description:
+ More fiddling with the FFI interface:
+  - Make constness 'c instead of rw wherever possible.  This eliminates
+    the need for certain explicit coercions.  (However, due to ML's
+    value polymorphism, there will still be many cases where explicit
+    coercions are necessary.  Phantom types are not the whole answer
+    to modeling a subtyping relationship in ML.)
+  - ro/rw coersions for pointers added.  (Avoids the detour through */&.)
+  - "printf" test example added to src/ml-nlffi-lib/Tests.  (Demonstrates
+    clumsy workaround for varargs problem.)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/01/15
+ Tag: <none>
+ Description:
+. Since COPY instructions are no longer native to the architecture,
+    a generic functor can be used to implement the expandCopies function.
+. Allowed EXPORT and IMPORT pseudo-op declarations to appear inside a
+    TEXT segment.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/15
+ Tag: blume-20020115-ffiupdates
+ Description:
+. Fix for bug resulting in single-precision float values being returned
+    incorrectly from FFI calls.
+. Small modifications to C FFI API:
+     - memory-allocation routines return straight objects (no options)
+       and raise an exception in out-of-memory situations
+     - unsafe extensions to cast between function pointers and pointers
+       from/to ints
+     - added structure C_Debug as an alternative to structure C where
+       pointer-dereferencing (|*| and |*!) always check for null-pointers
+     - added open_lib' to DynLinkage;  open_lib' works like open_lib
+       but also takes a (possibly empty) list of existing library handles
+       that the current library depends on
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/10
+ Tag: blume-20020110-newffigen
+ Description:
+. Updates to portable graph code.
+. Major update to ml-nlffigen and ml-nlffi-lib.  Things are much
+    more scalable now so that even huge interfaces such as the one
+    for GTK compile in finite time and space. :-)
+    See src/ml-nlffigen/README for details on what's new.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/01/09 14:31:35 EST 2002
+ Tag: george-20011206-rm-native-copy
+ Description:
+         Removed the native COPY and FCOPY instructions
+         from all the architectures and replaced it with the
+         explicit COPY instruction from the previous commit.
+         It is now possible to simplify many of the optimizations
+         modules that manipulate copies. This has not been
+         done in this change.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/12/06 16:50:13 EST 2001
+ Tag: george-20011206-mlrisc-instruction
+ Description:
+ Changed the representation of instructions from being fully abstract
+ to being partially concrete. That is to say:
+   from
+         type instruction
+   to
+         type instr                              (* machine instruction *)
+         datatype instruction =
+             LIVE of {regs: C.cellset, spilled: C.cellset}
+           | KILL of {regs: C.cellset, spilled: C.cellset}
+           | COPYXXX of {k: CB.cellkind, dst: CB.cell list, src: CB.cell list}
+           | ANNOTATION of {i: instruction, a: Annotations.annotation}
+           | INSTR of instr
+ This makes the handling of certain special instructions that appear on
+ all architectures easier and uniform.
+ LIVE and KILL say that a list of registers are live or killed at the
+ program point where they appear. No spill code is generated when an
+ element of the 'regs' field is spilled, but the register is moved to
+ the 'spilled' (which is present, more for debugging than anything else).
+ LIVE replaces the (now deprecated) DEFFREG instruction on the alpha.
+ We used to generate:
+         DEFFREG f1
+         f1 := f2 + f3
+         trapb
+ but now generate:
+         f1 := f2 + f3
+         trapb
+         LIVE {regs=[f1,f2,f3], spilled=[]}
+ Furthermore, the DEFFREG (hack) required that all floating point instruction
+ use all registers mentioned in the instruction. Therefore f1 := f2 + f3,
+ defines f1 and uses [f1,f2,f3]! This hack is no longer required resulting
+ in a cleaner alpha implementation. (Hopefully, intel will not get rid of
+ this architecture).
+ COPYXXX is intended to replace the parallel COPY and FCOPY  available on
+ all the architectures. This will result in further simplification of the
+ register allocator that must be aware of them for coalescing purposes, and
+ will also simplify certain aspects of the machine description that provides
+ callbacks related to parallel copies.
+ ANNOTATION should be obvious, and now INSTR represents the honest to God
+ machine instruction set!
+ The <arch>/instructions/<arch>Instr.sml files define certain utility
+ functions for making porting easier -- essentially converting upper case
+ to lower case. All machine instructions (of type instr) are in upper case,
+ and the lower case form generates an MLRISC instruction. For example on
+ the alpha we have:
+   datatype instr =
+      LDA of {r:cell, b:cell, d:operand}
+    | ...
+   val lda : {r:cell, b:cell, d:operand} -> instruction
+     ...
+ where lda is just (INSTR o LDA), etc.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/11/22 21:40:00 EST
+ Tag: Release_110_37
+ Description:
+ Release 110.37.  This time for real.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/11/21 16:35:00 EST
+ Tag: blume-20011121-foot-in-mouth
+ Description:
+ Removed the "Release_110_37" tag because of a serious bug.
+ This will be re-tagged once the bug is fixed.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/11/21 16:14:00 EST
+ Tag: blume-20011121-forgottenfile
+ Description:
+ Forgot to add a file.  (Just a .tex-file -- part of
+ the CM manual source.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/11/21 16:10:00 EST
+ Tag: blume-20011121-invalid_110_37
+ Description:
+ Note: I removed the original tag "Release_110_37" from this commit
+       because we found a serious bug in all non-x86 backends.
+       - Matthias
+. Modifications to the SML/NJ code generator and to the runtime system
+    so that code object name strings are directly inserted into code
+    objects at code generation time.  The only business the runtime system
+    has with this is now to read the name strings on occasions.
+    (The encoding of the name string has also changed somewhat.)
+. CM now implements a simple "set calculus" for specifying export lists.
+    In particular, it is now possible to refer to the export lists of
+    other libraries/groups/sources and form unions as well as differences.
+    See the latest CM manual for details.
+. An separate notion of "proxy" libraries has again be eliminated from
+    CM's model.  (Proxy libraries are now simply a special case of using
+    the export list calculus.)
+. Some of the existing libraries now take advantage of the new set
+    calculus.
+    (Notice that not all libraries have been converted because some
+    of the existing .cm-files are supposed to be backward compatible
+    with 110.0.x.)
+. Some cleanup in stand-alone programs.  (Don't use "exnMessage" -- use
+    "General.exnMessage"!  The former relies on a certain hook to be
+    initialized, and that often does not happen in the stand-alone case.)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/11/21  13:56:18 EST
+ Tag: george-2001121-pseudo-ops
+ Description:
+   Implemented a complete redesign of MLRISC pseudo-ops. Now there
+   ought to never be any question of incompatabilities with
+   pseudo-op syntax expected by host assemblers.
+   For now, only modules supporting GAS syntax are implemented
+   but more should follow, such as MASM, and vendor assembler
+   syntax, e.g. IBM as, Sun as, etc.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/11/14 11:52:00 EST
+ Tag: blume-20011114-srcname
+ Description:
+. Routed the name of the current source file to mlriscgen where it
+    should be directly emitted into the code object.  (This last part
+    is yet to be done.)
+. Some cleanup of the pgraph code to make it match the proposal that
+    I put out the other day.  (The proposal notwithstanding, things are
+    still in flux here.)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/11/14 09:44:04 EST
+ Tag:
+ Description:
+   Fix for a backpatching bug reported by Allen.
+   Because the boundary between short and long span-dependent
+   instructions is +/- 128, there are an astounding number of
+   span-dependent instructions whose size is over estimated.
+   Allen came up with the idea of letting the size of span
+   dependent instructions be non-monotonic, for a maxIter
+   number of times, after which the size must be monotonically
+   increasing.
+   This table shows the number of span-dependent instructions
+   whose size was over-estimated as a function of maxIter, for the
+   file Parse/parse/ml.grm.sml:
+      maxIter            # of instructions:
+                     687
+                     438
+                     198
+                       0
+   In compiling the compiler, there is no significant difference in
+   compilation speed between maxIter=10 and maxIter=40. Actually,
+   my measurements showed that maxIter=40 was a tad faster than
+   maxIter=10! Also 96% of the  files in the compiler reach a fix
+   point within 13 iterations, so fixing maxIter at 40, while high,
+   is okay.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/10/31 15:25:00 EST
+ Tag: blume-20011031-pgraph
+ Description:
+ CKIT:
+ * Changed the "Function" constructor of type Ast.ctype to carry optional
+   argument identifiers.
+ * Changed the return type of TypeUtil.getFunction accordingly.
+ * Type equality ignores the argument names.
+ * TypeUtil.composite tries to preserve argument names but gives up quickly
+   if there is a mismatch.
+ installation script:
+ * attempts to use "curl" if available (unless "wget" is available as well)
+ CM:
+ * has an experimental implementation of "portable graphs" which I will
+   soon propose as an implementation-independent library format
+ * there are also new libraries $/pgraph.cm and $/pgraph-util.cm
+ NLFFI-LIB:
+ * some cleanup (all cosmetic)
+ NLFFIGEN:
+ * temporarily disabled the mechanism that suppresses ML output for
+   C definitions whose identifiers start with an underscore character
+ * generate val bindings for enum constants
+ * user can request that only one style (light or heavy) is being used;
+   default is to use both (command-line arguments: -heavy and -light)
+ * fixed bug in handling of function types involving incomplete pointers
+ * generate ML entry points that take record arguments (i.e., using
+   named arguments) for C functions that have a prototype with named
+   arguments
+   (see changes to CKIT)
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2001/10/27 20:34:00 EDT
+ Tag: leunga-20011027-x86-fast-fp-call
+ Description:
+    Fixed the bug described in blume-20010920-slowfp.
+    The fix involves
+. generating FCOPYs in FSTP in ia32-svid
+. marking a CALL with the appropriate annotation
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/10/16 11:32:00 EDT
+ Tag: blume-20011016-netbsd
+ Description:
+ Underscore patch from Chris Richards (fixing problem with compiling
+ runtime system under recent NetBSD).
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2001/10/12 17:18:32 EDT 2001
+ Tag: leung-20011012-x86-printflowgraph
+ Description:
+ X86RA now uses a valid (instead of dummy) PrintFlowgraph module.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/10/11 23:51:34 EDT
+ Tag: george-20011011-too-many-instrs
+ Description:
+ The representation of a program point never expected to see more
+ than 65536 instructions in a basic block!
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/10/09 09:41:37 EDT
+ Tag: george-20011008-mlrisc-labels
+ Description:
+ Changed the machine description files to support printing of
+ local and global labels in assembly code, based on host assembler
+ conventions.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/09/25 15:25:00 EDT
+ Tag: blume-20010925-exninfo
+ Description:
+ I provided a non-hook implementation of exnName (at the toplevel) and
+ made the "dummy" implementation of exnMessage (at the toplevel) more
+ useful: if nothing gets "hooked in", then at least you are going to
+ see the exception name and a message indicating why you don't see more.
+ [For the time being, programs that need exnMessage and want to use
+ ml-build should either use General.exnMessage (strongly recommended) or
+ refer to structure General at some other point so that CM sees a
+ static dependency.]
+ [Similar remarks go for "print" and "use":  If you want to use their
+ functionality in stand-alone programs generated by ml-build, then use
+ TextIO.output and Backend.Interact.useFile (from $smlnj/compiler.cm).]
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/09/20 17:28:00 EDT
+ Tag: blume-20010920-slowfp
+ Description:
+ Allen says that x86-fast-fp is not safe yet, so I turned it off again...
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/09/20 17:20:00 EDT
+ Tag: blume-20010920-canonicalpaths
+ Description:
+. Updated the BOOT file (something that I forgot to do earlier).
+. Small internal change to CM so that it avoids "/../" in filenames
+    as much as possible (but only where it is safe).
+. Changed config/_run-sml (resulting in a changed bin/.run-sml) so
+    that arguments that contain delimiters are passed through correctly.
+    This change also means that all "special" arguments of the form
+    @SMLxxx... must come first.
+. Changed install script to put relative anchor names for tool commands
+    into pathconfig.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ >>>>>>> 1.169
+ Date: 2001/09/18 15:35:00 EDT
+ Tag: blume-20010918-readme11036
+ Description:
+ Added README files.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/09/18 11:45:00 EDT
+ Tag: Release_110_36 (retag)
+ Description:
+ Fixed mistake in config/preloads. Retagged as 110.36.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/09/18 09:40:00 EDT
+ Tag: Release_110_36_orig (tag changed)
+ Description:
+ New version (110.36).  New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/09/14 16:15:00 EDT
+ Tag: blume-20010914-x86fastfp
+ Description:
+ John committed some changes that Allen made, in particular a (hopefully)
+ correctly working version of the x86-fp module.
+ I changed the default setting of the Control.MLRISC.getFlag "x86-fast-fp"
+ flag to "true".  Everything seems to compile to a fixpoint ok, and
+ "mandelbrot" speeds up by about 15%.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/09/13 11:20:00 EDT
+ Tag: blume-20010913-minimal
+ Description:
+. Stefan Monnier's patch to fix a miscompilation problem that
+    was brought to light by John Reppy's work on Moby.
+. Implemented a minimal "structure Compiler" that contains just
+    "version" and "architecture".  The minimal version will be
+    available when the full version is not.  This is for backward-
+    compatibility with code that wants to test Compiler.version.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/28 14:03:00 EDT
+ Tag: blume-20010828-ml-lex
+ Description:
+ Fix for bug 1581, received from Neophytos Michael.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/27 11:20:00 EDT
+ Tag: blume-20010827-readme11035
+ Description:
+ Fleshed out the README file for 110.35.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/24 17:10:00 EDT
+ Tag: Release_110_35
+ Description:
+ New version number (110.35).  New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/08/24 13:47:18 EDT 2001
+ Tag: george-20010824-MLRISC-graphs
+ Description:
+  removed clusters from MLRISC completely and replaced with graphs.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/23 17:50:00 EDT
+ Tag: blume-20010823-toplevel
+ Description:
+ - some reorganization of the code that implements various kinds of
+   environments in the compiler (static, dynamic, symbolic, combined)
+ - re-implemented the EnvRef module so that evalStream works properly
+   (if the stream contains references to "use", "CM.make", etc.)
+ - cleaned up evalloop.sml and interact.sml (but they need more cleaning)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/20 15:50 EDT
+ Tag: blume20010820-slipup
+ Description:
+ I forgot to commit a few files.  Here they are...
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/20 15:35:00 EDT
+ Tag: blume-20010820-debugprof
+ Description:
+ !!!! NEW BOOTFILES !!!!
+ This is another round of reorganizing the compiler sources.  This
+ time the main goal was to factor out all the "instrumentation"
+ passes (for profiling and backtracing) into their own library.
+ The difficulty was to do it in such a way that it does not depend
+ on elaborate.cm but only on elabdata.cm.
+ Therefore there have been further changes to both elaborate.cm and
+ elabdata.cm -- more "generic" things have been moved from the former
+ to the latter.  As a result, I was forced to split the assignment
+ of numbers indicating "primtyc"s into two portions: SML-generic and
+ SML/NJ-specific.  Since it would have been awkward to maintain,
+ I bit the bullet and actually _changed_ the mapping between these
+ numbers and primtycs.  The bottom line of this is that you need
+ a new set of bin- and bootfiles.
+ I have built new bootfiles for all architectures, so doing a fresh
+ checkout and config/install.sh should be all you need.
+ The newly created library's name is
+     $smlnj/viscomp/debugprof.cm
+ and its sources live under
+     src/compiler/DebugProf
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/15 17:15:00 EDT
+ Tag: blume-20010815-compreorg
+ Description:
+ This is a first cut at reorganizing the CM libraries that make up the
+ core of the compiler.  The idea is to separate out pieces that could
+ be used independently by tools, e.g., the parser, the typechecker, etc.
+ The current status is a step in this direction, but it is not quite
+ satisfactory yet.  Expect more changes in the future.
+ Here is the current (new) organization...
+     What used to be $smlnj/viscomp/core.cm is now divided into
+     six CM libraries:
+          $smlnj/viscomp/basics.cm
+                        /parser.cm
+                        /elabdata.cm
+                        /elaborate.cm
+                        /execute.cm
+                        /core.cm
+     The CM files for these libraries live under src/system/smlnj/viscomp.
+     All these libraries are proxy libraries that contain precisely
+     one CM library component.  Here are the locations of the components
+     (all within the src/compiler tree):
+          Basics/basics.cm
+          Parse/parser.cm
+          ElabData/elabdata.cm
+          Elaborator/elaborate.cm
+          Execution/execute.cm
+          core.cm
+      [This organization is the same that has been used already
+      for a while for the architecture-specific parts of the visible
+      compiler and for the old version of core.cm.]
+      As you will notice, many source files have been moved from their
+      respective original locations to a new home in one of the above
+      subtrees.
+      The division of labor between the new libraries is the following:
+          basics.cm:
+             - Simple, basic definitions that pertain to many (or all) of
+               the other libraries.
+          parser.cm:
+             - The SML parser, producing output of type Ast.dec.
+             - The type family for Ast is also defined and exported here.
+          elabdata.cm:
+             - The datatypes that describe input and output of the elaborator.
+               This includes types, absyn, and static environments.
+          elaborator.cm:
+             - The SML/NJ type checker and elaborator.
+               This maps an Ast.dec (with a given static environment) to
+               an Absyn.dec (with a new static environment).
+             - This libraries implements certain modules that used to be
+               structures as functors (to remove dependencies on FLINT).
+          execute.cm:
+             - Everything having to do with executing binary code objects.
+             - Dynamic environments.
+          core.cm:
+             - SML/NJ-specific instantiations of the elaborator and MLRISC.
+             - Top-level modules.
+             - FLINT (this should eventually become its own library)
+ Notes:
+ I am not 100% happy with the way I separated the elaborator (and its
+ data structures) from FLINT.  Two instances of the same problem:
+. Data structures contain certain fields that carry FLINT-specific
+        information.  I hacked around this using exn and the property list
+        module from smlnj-lib.  But the fact that there are middle-end
+        specific fields around at all is a bit annoying.
+. The elaborator calculates certain FLINT-related information.  I tried
+        to make this as abstract as I could using functorization, but, again,
+        the fact that the elaborator has to perform calculations on behalf
+        of the middle-end at all is not nice.
+. Having to used exn and property lists is unfortunate because it
+        weakens type checking.  The other alternative (parameterizing
+        nearly *everything*) is not appealing, though.
+ I removed the "rebinding =" warning hack because due to the new organization
+ it was awkward to maintain it.  As a result, the compiler now issues some of
+ these warnings when compiling init.cmi during bootstrap compilation. On
+ the plus side, you also get a warning when you do, for example:
+    val op = = Int32.+
+ which was not the case up to now.
+ I placed "assign" and "deref" into the _Core structure so that the
+ code that deals with the "lazy" keyword can find them there.  This
+ removes the need for having access to the primitive environment
+ during elaboration.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/08/13
+ Tag: blume-20010813-closures
+ Description:
+ This fix was sent to us by Zhong Shao.  It is supposed to improve the
+ performance of certain loops by avoiding needless closure allocation.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/07/31 10:03:23 EDT 2001
+ Tag: george-20010731-x86-fmalloc
+ Description: Fixed bug in x86 calls
+     There was a bug where call instructions would mysteriously
+     vanish. The call instruction had to be one that returned
+     a floating point value.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/07/19 16:36:29 EDT 2001
+ Tag: george-20010719-simple-cells
+ Description:
+ I have dramatically simplified the interface for CELLS in MLRISC.
+ In summary, the cells interface is broken up into three parts:
+. CellsBasis : CELLS_BASIS
+         CellsBasis is a top level structure and common for all
+         architectures.  it contains the definitions of basic datatypes
+         and utility  functions over these types.
+. functor Cells() : CELLS
+         Cells generates an interface for CELLS that incorporates the
+         specific resources on the target architecture, such as the
+         presence of special register classes, their number and size,
+         and various useful substructures.
+. <ARCH>CELLS
+         e.g. SparcCells: SPARCCELLS
+         <ARCH>CELLS usually contains additional bindings for special
+         registers  on the architecture, such as:
+                 val r0 : cell           (* register zero *)
+                 val y : cell            (* Y register *)
+                 val psr : cell          (* processor status register *)
+                 ...
+         The structure returned by applying the Cells functor is opened
+         in this interface.
+ The main implication of all this is that the datatypes for cells is
+ split between CellsBasis and CELLS -- a fairly simple change for user
+ code.
+ In the old scheme the CELLS interface had a definitional binding of
+ the form:
+         signature CELLS = sig
+            structure CellsBasis = CellsBasis
+            ...
+         end
+ With all the sharing constraints that goes on in MLRISC, this old
+ design  quickly leads to errors such as:
+         "structure definition spec inside of sharing ... "
+ and appears to require an unacceptable amount of sharing and where
+ constraint hackery.
+ I think this error message (the interaction of definitional specs and
+ sharing) requires more explanation on our web page.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/07/19 15:00:00 EDT
+ Tag: blume-20010719-libreorg
+ Description:
+ This update puts together a fairly extensive but straightforward change
+ to the way the libraries that implement the interactive system are
+ organized:
+    The biggest change is the elimination of structure Compiler.  As a
+    replacement for this structure, there is now a CM library
+    (known as $smlnj/compiler.cm or $smlnj/compiler/current.cm)
+    that exports all the substructures of the original structure Compiler
+    directly.  So instead of saying Compiler.Foo.bar one now simply
+    says Foo.bar.  (The CM libraries actually export a collection of
+    structures that is richer than the collection of substructures of
+    structure Compiler.)
+    To make the transition smooth, there is a separate library called
+    $smlnj/compiler/compiler.cm which puts together and exports the
+    original structure Compiler (or at least something very close to it).
+    There are five members of the original structure Compiler
+    that are not exported directly but which instead became members
+    of a new structure Backend (described by signature BACKEND).  These are:
+    structure Profile (: PROFILE), structure Compile (: COMPILE), structure
+    Interact (: INTERACT), structure Machine (: MACHINE), and val
+    architecture (: string).
+    Structure Compiler.Version has become structure CompilerVersion.
+    Cross-compilers for alpha32, hppa, ppc, sparc, and x86 are provided
+    by $smlnj/compiler/<arch>.cm where <arch> is alpha32, hppa, ppc, sparc,
+    or x86, respectively.
+    Each of these exports the same frontend structures that
+    $smlnj/compiler.cm exports.  But they do not have a structure Backend
+    and instead export some structure <Arch>Backend where <Arch> is Alpha32,
+    Hppa, PPC, Sparc, or X86, respectively.
+    Library $smlnj/compiler/all.cm exports the union of the exports of
+    $smlnj/compiler/<arch>.cm
+    There are no structures <Arch>Compiler anymore, use
+    $smlnj/compiler/<arch>.cm instead.
+    Library host-compiler-0.cm is gone.  Instead, the internal library
+    that instantiates CM is now called cm0.cm.  Selection of the host
+    compiler (backend) is no longer done here but. (Responsibility for it
+    now lies with $smlnj/compiler/current.cm.  This seems to be more
+    logical.)
+    Many individual files have been moved or renamed.  Some files have
+    been split into multiple files, and some "dead" files have been deleted.
+ Aside from these changes to library organization, there are also changes
+ to the way the code itself is organized:
+    Structure Binfile has been re-implemented in such a way that it no
+    longer needs any knowledge of the compiler.  It exclusively deals
+    with the details of binfile layout.  It no longer invokes the
+    compiler (for the purpose of creating new prospective binfile
+    content), and it no longer has any knowledge of how to interpret
+    pickles.
+    Structure Compile (: COMPILE) has been stripped down to the bare
+    essentials of compilation.  It no longer deals with linking/execution.
+    The interface has been cleaned up considerably.
+    Utility routines for dealing with linking and execution have been
+    moved into their own substructures.
+    (The ultimate goal of these changes is to provide a light-weight
+    binfile loader/linker (at least for, e.g., stable libraries) that
+    does not require CM or the compiler to be present.)
+ CM documentation has been updated to reflect the changes to library
+ organization.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/07/10 17:30:00 EDT
+ Tag: Release_110_34
+ Description:
+ Minor tweak to 110.34 (re-tagged):
+   - README.html file added to CVS repository
+   - runtime compiles properly under FreeBSD 3.X and 4.X
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/07/10 17:30:00 EDT
+ Tag: Release_110_34
+ Description:
+ New version number (110.34). New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/07/09 16:00:00 EDT
+ Tag: blume-20010709-more-varargs
+ Description:
+ I changed the handling of varargs in ml-nlffigen again:
+ The ellipsis ... will now simply be ignored (with an accompanying warning).
+ The immediate effect is that you can actually call a varargs function
+ from ML -- but you can't actually supply any arguments beyond the ones
+ specified explicitly.  (For example, you can call printf with its format
+ string, but you cannot pass additional arguments.)
+ This behavior is only marginally more useful than the one before, but
+ it has the advantage that a function or, more importantly, a function
+ type never gets dropped on the floor, thus avoiding follow-up problems with
+ other types that refer to the offending one.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/07/09 11:25:00 EDT
+ Tag: blume-20010709-varargs
+ Description:
+. ckit-lib.cm now exports structure Error
+. ml-nlffigen reports occurences of "..." (i.e., varargs function types)
+    with a warning accompanied by a source location.  Moreover, it
+    merely skips the offending function or type and proceeds with the
+    rest of its work.u  As a result, one can safely feed C code containing
+    "..." to ml-nlffigen.
+. There are some internal improvements to CM, providing slightly
+    more general string substitutions in the tools subsystem.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/27 15:10:00 EDT
+ Tag: blume-20010627-concur
+ Description:
+ Fixed a small bug in CM's handling of parallel compilation.
+ (You could observe the bug by Control-C-interrupting an ordinary
+ CMB.make or CM.stabilize and then attaching some compile servers.
+ The result was that all of a sudden the previously interrupted
+ compilation would continue on its own.  This was because of
+ an over-optimization: CM did not bother to clean out certain queues
+ when no servers were attached "anyway", resulting in the contents
+ of these queues to grab control when new servers did get attached.)
+ There is also another minor update to the CM manual.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/26 16:15:00 EDT
+ Tag: blume-20010626-cmdoc
+ Description:
+ Minor typo fixed in CM manual (syntax diagram for libraries).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/25 22:55:00 EDT
+ Tag: blume-20010625-x86pc
+ Description:
+ Fixed a nasty bug in the X86 assembly code that caused signal
+ handlers to fail (crash) randomly.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/25 12:05:00 EDT
+ Tag: blume-20010625-nlffigen
+ Description:
+ This update fixes a number of minor bugs in ml-nlffigen as reported by
+ Nick Carter <nbc@andrew.cmu.edu>.
+. Silly but ok typedefs of the form "typedef void myvoid;" are now accepted.
+. Default names for generated files are now derived from the name of
+      the C file *without its directory*.  In particular, this causes generated
+      files to be placed locally even if the C file is in some system directory.
+. Default names for generated signatures and structures are also derived
+      from the C file name without its directory.  This avoids silly things
+      like "structure GL/GL".
+      (Other silly names are still possible because ml-nlffigen does not do
+       a thorough check of whether generated names are legal ML identifiers.
+       When in doubt, use command line arguments to force particular names.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/21 12:25:00 EDT
+ Tag: blume-20010621-eXene
+ Description:
+ eXene now compiles and (sort of) works again.
+ The library name (for version > 110.33) is $/eXene.cm.
+ I also added an new example in src/eXene/examples/nbody.  See the
+ README file there for details.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/20 16:40:00 EDT
+ Tag: blume-20010620-cml
+ Description:
+ CML now compiles and works again.
+ Libraries (for version > 110.33):
+   $cml/cml.cm            Main CML library.
+   $cml/basis.cm          CML's version of $/basis.cm.
+   $cml/cml-internal.cm   Internal helper library.
+   $cml/core-cml.cm       Internal helper library.
+   $cml-lib/trace-cml.cm  Tracing facility.
+   $cml-lib/smlnj-lib.cm  CML's version of $/smlnj-lib.cm
+ The installer (config/install.sh) has been taught how to properly
+ install this stuff.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/19 17:55:00 EDT
+ Tag: blume-20010619-instantiate
+ Description:
+ This un-breaks the fix for bug 1432.
+ (The bug was originally fixed in 110.9 but I broke it again some
+ time after that.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/19 17:25:00 EDT
+ Tag: blume-20010619-signals
+ Description:
+ This should (hopefully) fix the long-standing signal handling bug.
+ (The runtime system was constructing a continuation record with an
+ incorrect descriptor which would cause the GC to drop data on the floor...)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/15 15:05:00 EDT
+ Tag: blume-20010615-moresparc
+ Description:
+ Here is a short late-hour update related to Sparc c-calls:
+  -- made handling of double-word arguments a bit smarter
+  -- instruction selection phase tries to collapse certain clumsily
+     constructed ML-Trees; typical example:
+         ADD(ty,ADD(_,e,LI d1),LI d2)  ->  ADD(ty,e,LI(d1+d2))
+     This currently has no further impact on SML/NJ since mlriscGen does
+     not seem to generate such patterns in the first place, and c-calls
+     (which did generate them in the beginning) has meanwhile been fixed
+     so as to avoid them as well.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/15 15:05:00 EDT
+ Tag: blume-20010615-sparc
+ Description:
+ The purpose of this update is to provide an implementation of NLFFI
+ on Sparc machines.
+ Here are the changes in detail:
+    * src/MLRISC/sparc/c-calls/sparc-c-calls.sml is a new file containing
+    the Sparc implementation of the c-calls API.
+    * The Sparc backend of SML/NJ has been modified to uniformely use %fp
+    for accessing the ML frame.  Thus, we have a real frame pointer and
+    can freely modify %sp without need for an omit-frame-ptr phase.
+    The vfp logic in src/compiler/CodeGen/* has been changed to accomodate
+    this case.
+    * ml-nlffigen has been taught to produce code for different architectures
+    and calling conventions.
+    * In a way similar to what was done in the x86 case, the Sparc
+    backend uses its own specific extension to mltree.  (For example,
+    it needs to be able to generate UNIMP instructions which are part
+    of the calling convention.)
+    * ml-nlffi-lib was reorganized to make it more modular (in particular,
+    to make it easier to plug in new machine- and os-dependent parts).
+ There are some other fairly unrelated bug fixes and cleanups as well:
+    * I further hacked the .cm files for MLRISC tools (like MDLGen) so
+    that they properly share their libraries with existing SML/NJ libraries.
+    * I fixed a minor cosmetic bug in CM, supressing certain spurious
+    follow-up error messages.
+    * Updates to CM/CMB documentation.
+ TODO items:
+    * MLRISC should use a different register as its asmTemp on the Sparc.
+      (The current %o2 is a really bad choice because it is part of the
+      calling conventions, so things might interfere in unexpected ways.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/07
+ Tag: blume-20010607-calls
+ Description:
+ A number of internal changes related to C calls and calling conventions:
+. ML-Tree CALL statements now carry a "pops" field.  It indicates the
+    number of bytes popped implicitly (by the callee).  In most cases
+    this field is 0 but on x86/win32 it is some non-zero value.  This
+    is information provided for the benefit of the "omit-frameptr" pass.
+. The CALL instruction on the x86 carries a similar "pops" field.
+    The instruction selection phase copies its value from the ML-Tree
+    CALL statement.
+. On all other architectures, the instruction selection phase checks
+    whether "pops=0" and complains if not.
+. The c-calls implementation for x86 now accepts two calling conventions:
+    "ccall" and "stdcall".  When "ccall" is selected, the caller cleans
+    up after the call and pops is set to 0.  For "stdcall", the caller
+    does nothing, leaving the cleanup to the callee; pops is set to
+    the number of bytes that were pushed onto the stack.
+. The cproto decoder (compiler/Semant/types/cproto.sml) now can
+    distinguish between "ccall" and "stdcall".
+. The UNIMP instruction has been added to the supported Sparc instruction
+    set. (This is needed for implementing the official C calling convention
+    on this architecture.)
+. I fixed some of the .cm files under src/MLRISC/Tools to make them
+    work with the latest CM.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/05 15:10:00 EDT
+ Tag: blume-20010605-cm-index
+ Description:
+. The "lambdasplit" parameter for class "sml" in CM has been documented.
+. CM can now generate "index files".  These are human-readable files
+    that list on a per-.cm-file basis each toplevel symbol defined or
+    imported.  The location of the index file for
+    <p>/<d>.cm is <p>/CM/INDEX/<d>.cm.
+    To enable index-file generation, set CM.Control.generate_index to true
+    or export an environment-symbol: export CM_GENERATE_INDEX=true.
+    The CM manual has been updated accordingly.
+. I made some slight modifications to the c-calls API in MLRISC.
+      a) There is now a callback to support saving/restoring of
+         dedicated but caller-save registers around the actual call
+         instruction.
+      b) One can optionally specify a comment-annotation for the
+         call instruction.
+. SML/NJ (mlriscGen.sml) uses this new API for the rawccall primop.
+    (For example, the comment annotation shows the C prototype of
+     the function being called.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/06/01 13:30:00 EDT
+ Tag: blume-20010601-nlffi-cleanup
+ Description:
+ This is mostly a cleanup of MLFFI stuff:
+    - some signature files have been put into a more exposed place
+    - the ugly 'f type parameter is gone (simplifies types tremendously!)
+    - ml-nlffigen changed accordingly
+    - tutorial updated
+ Other changes:
+    - author's affiliation in CM manual(s) updated
+    - some more recognized keywords added to Allen's sml.sty
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/25 15:30:00 EDT
+ Tag: blume-20010525-iptr
+ Description:
+   - put the official 110.33-README (as it appears on the ftp server) under
+     CVS
+   - fixed a small bug related to incomplete pointer types in
+     ml-nlffigen
+   - small cosmetic change to the ml-nlffi-lib's "arr" type constructor
+     (it does not need the 'f type parameter)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/23 14:30:00 EDT
+ Tag: Release_110_33
+ Description:
+ New version number (110.33).  New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/22 18:06:00 EDT
+ Tag: blume-20010522-targets
+ Description:
+ Made install.sh use file config/targets.customized if it exists, falling
+ back to config/targets if it doesn't.  This way one can have a customized
+ version of the targets file without touching the "real thing", thus
+ eliminating the constant fear of accidentally checking something bogus
+ back into the CVS repository...  (File config/targets.customized must
+ not be added to the repository!)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/22 16:30:00 EDT
+ Tag: blume-20010522-minitut
+ Description:
+. Bug fix in ml-nlffigen; now (hopefully) correctly handling
+    struct returns.
+. Added src/ml-nlffi-lib/Doc/mini-tutorial.txt.  This is some very
+    incomplete, preliminary documentation for NLFFI.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/14 11:30:00 EDT
+ Tag: blume-20010514-script
+ Description:
+ Some bugs in install script fixed.
+ In addition to that I also made a slight change to the NLFFI API:
+ Functors generated by ml-nlffigen now take the dynamic library as a
+ straight functor argument, not as a suspended one.  (The original
+ functor code used to force the suspension right away anyway, so there
+ was nothing gained by this complication of the interface.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/11 14:35:00 EDT
+ Tag: blume-20010511-ml-nlffi
+ Description:
+ I finally took the plunge and added my new FFI code to the main
+ repository.  For x86-linux it is now ready for prime-time.
+ There are two new subdirectories of "src":
+   - ml-nlffi-lib:
+        The utility library for programs using the FFI interface.
+        Here is the implementation of $/c.cm and its associated low-level
+        partners $/c-int.cm and $/memory.cm.
+   - ml-nlffigen:
+        A stand-alone program for generating ML glue code from C source
+        code.
+ Building ml-nlffigen requires $/ckit-lib.cm.
+ The config/install.sh script has been updates to do the Right Thing
+ (hopefully).
+ Notice that the source tree for the C-Kit will not be put under "src"
+ but directly under the installation root directory.  (This is the
+ structure that currently exists on the CVS server when you check out
+ module "sml".)  Fortunately, config/install.sh knows about this oddity.
+ Bugs: No documentation yet.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/09 16:35:00 EDT
+ Tag: blume-20010509-cpscontract
+ Description:
+ Fixed a bug in the accounting code in cpsopt/contract.sml.  (The
+ wrapper/unwrapper elimination did not decrement usage counts and some
+ dead variables got overlooked by the dead-up logic.)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/05/08  17:26:09 EDT
+ Tag: george-20010508-omit-frameptr
+ Description:
+ Changes to implement the omit-frame-pointer optimization to support
+ raw C calls. For now, there is only support on the Intel x86, but
+ other architectures will follow as more experience is gained with this.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/07 14:40:00 EDT
+ Tag: blume-20010507-proxies
+ Description:
+ I made into "proxy libraries" all libraries that qualify for such a
+ change.  (A qualifying library is a library that has another library or
+ groups as its sole member and repeats that member's export list
+ verbatim.  A proxy library avoids this repetition by omitting its export
+ list, effectively inheriting the list that its (only) member exports.
+ See the CM manual for more explanation.)
+ The main effect is that explicit export lists for these libraries
+ do not have to be kepts in sync, making maintenance a bit easier.
+ I also added copyright notices to many .cm-files.
+ Last but not least, I made a new set of bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/04 17:00:00 EDT
+ Tag: blume-20010504-cm-lsplit
+ Description:
+. John merged pending changes to $/smlnj-lib.cm
+. Allen's previous change accidentally backed out of one of Lal's
+    earlier changes.  I undid this mistake (re-introducing Lal's change).
+. I used the new topOrder' function from graph-scc.sml (from $/smlnj-lib.cm)
+    within the compiler where applicable.  There is some code simplification
+    because of that.
+. The "split" phase (in FLINT) is now part of the default list of phases.
+    Compiler.Control.LambdaSplitting.* can be used to globally control the
+    lambda-splitting (cross-module-inlining) engine.  In addition to that,
+    it can now also be controlled on a per-source basis: CM has been taught
+    a new tool parameter applicable to ML source files.
+    - To turn lambda-splitting off completely:
+         local open Compiler.Control.LambdaSplitting in
+             val _ = set Off
+         end
+    - To make "no lambda-splitting" the global default (but allow per-source
+      overriding); this is the initial setting:
+         local open Compiler.Control.LambdaSplitting in
+             val _ = set (Default NONE)
+         end
+    - To make "lambda-splitting with aggressiveness a" the global default
+      (and allow per-source overriding):
+         local open Compiler.Control.LambdaSplitting in
+             val _ = set (Default (SOME a))
+         end
+    - To turn lambda-splitting off for a given ML souce file (say: a.sml)
+      write (in the respective .cm-file):
+         a.sml (lambdasplitting:off)
+    - To turn lambda-splitting for a.sml on with minimal aggressiveness:
+         a.sml (lambdasplitting:on)
+    - To turn lambda-splitting for a.sml on with aggressiveness <a> (where
+      <a> is a decimal non-negative integer):
+         a.sml (lambdasplitting:<a>)
+    - To turn lambda-splitting for a.sml on with maximal aggressiveness:
+         a.sml (lambdasplitting:infinity)
+    - To use the global default for a.sml:
+         a.sml (lambdasplitting:default)
+      or simply
+         a.sml
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2001/05/04 01:57:00 EDT
+ Tag: leunga-20010504-sync
+ Description:
+   MLRISC features.
+. Fix to CMPXCHG instructions.
+. Changed RA interface to allow annotations in callbacks.
+. Added a new method to the stream interface to allow annotations updates.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/05/01 11:45:00 EDT
+ Tag: blume-20010501-pcedittmp
+ Description:
+ Changed install.sh to use the current working directory instead of
+ /usr/tmp for a temporary file (pcedittmp).  The previous choice
+ of /usr/tmp caused trouble with MacOS X because of file premission
+ problems.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/04/20 11:10:00 EDT
+ Tag: blume-20010420-inMLflag
+ Description:
+  - added vp_limitPtrMask to vproc-state.h
+    (for use by the raw-C-calls mechanism to implement proper interrupt
+     handling)
+  - made the ML compiler aware of various data-structure offsets so it
+    can generate code for accessing the vp_inML flag and vp_limitPtrMask
+  - tweaked mlriscGen.sml to have it emit interrupt-handling code for
+    raw C-calls
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2001/04/20 09:15:28 EDT
+ Tag: george-20010420-macosX
+ Description:
+  - Changes to port to Mac OS X; Darwin.
+  - In the process I found that sqrt was broken on the PPC, because the
+    fsqrt instruction is not implemented.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/04/18 12:45:00 EDT
+ Tag: blume-20010418-ccalls
+ Description:
+  - fixed two off-by-4 errors in the x86-specific c-calls implementation
+    (this bug prevented structure arguments containing pointers from being
+     passed correctly)
+  - changed the raw-C-call code in mlriscGen.sml in such a way that
+    structure arguments are represented as a pointer to the beginning
+    of the structure (instead of having a series of synthesized arguments,
+    one for each structure member)
+  - made makeml script's verbosity level configurable via environment
+    variable (MAKEML_VERBOSITY)
+  - eliminated placeholder implementations for f32l, w16s, i16s, and f32s
+    in rawmem-x86.sml; we are now using the real thing
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/03/22 16:25:00 EST
+ Tag: blume-20010322-bootfiles
+ Description:
+ Created a new set of bootfiles (for your automatic installation convenience).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/03/22 15:10:00 EST
+ Tag: blume-20010322-rawmem-parcm
+ Description:
+. All "raw memory access" primitives for the new FFI are implemented now
+    (at least on the x86).
+. Some further cleanup of CM's parallel make mechanism.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/03/19 17:53:00 EST
+ Tag: blume-20010319-parallel
+ Description:
+ Parallel make (using compile servers) now works again.
+ To this end, CM.stabilize and CMB.make have been modified to work in
+ two passes when compile servers are attached:
+. Compile everything, do not perform stabilization; this pass
+       uses compile servers
+. Stabilize everything; this pass does not use compile servers
+ If there are no compile servers, the two passes are combined into one
+ (as before).  Splitting the passes increases the inherent parallelism
+ in the dependency graph because the entire graph including all
+ libraries is available at the same time.  This, in turn, improves
+ server utilization.  The downside is that the master process will
+ have to do some extra work after compilation is done (because for
+ technical reasons it must re-read all the binfiles during stabilization).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/03/16 12:22:00 EST
+ Tag: blume-20010316-bootfiles
+ Description:
+ Created a new set of bootfiles (for your automatic installation convenience).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/03/16 11:00:00 EST
+ Tag: blume-20010316-MLTREE-fixup
+ Description:
+ This is a minor fixup for an (untagged) earlier commit by Allen.
+ (A file was missing).
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: Mon Mar  5 18:54:57 EST 2001
+ Tag: leunga-20010305-cut-support
+. New support for alternative control-flow in MLTREE.
+    Currently we support
+       FLOW_TO(CALL ...., [k1,...,kn])
+    This is needed for 'cuts to' in C-- and try/handle-like constructs
+    in Moby
+    New assembler flag "asm-show-cutsto" to turn on control-flow debugging.
+. Register Allocator
+    Changes in interface [from Fermin, John]
+. Alpha 8-bit SLL support [Fermin]
+. All architectures
+    A new module (ClusterExpandCopies) for expanding parallel copies.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2001/02/27 23:07:00 EST
+ Tag: leunga-20010227-minor-stuff
+. Alpha bug fix for CMOVNE
+. Handle mltree COND(..,FCMP ...,...)
+. Bug fix in simplifier
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/01/30 17:50:00 EST
+ Tag: blume-20010130-sync
+ Description:
+ This is just a minor update to sync my devel branch with the main brach.
+ The only visible change is the addition of some README files.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/01/12 23:30:00 JST
+ Tag: blume-20010112-bootfiles
+ Description:
+ Made a new set of bootfiles that goes with the current state of the
+ repository.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/01/12 21:20:00 JST
+ Tag: blume-20010112-sync
+ Description:
+ I am just flushing out some minor changes that had accumulated in
+ my private branch in order to sync with the main tree.  (This is
+ mainly because I had CVS trouble when trying to merge _into_ my
+ private branch.)
+ Most people should be completely unaffected by this.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: Thu Jan 11 21:03:00 EST 2001
+ Tag: leunga-20010111-labexp=mltree
+ Description:
+.  Removed the type LabelExp and replace it by MLTree.
+.  Rewritten mltree-simplify with the pattern matcher tool.
+.  There were some bugs in alpha code generator which would break
+-bit code generation.
+.  Redo the tools to generate code with the
+.  The CM files in MLRISC (and in src/system/smlnj/MLRISC)
+     are now generated by perl scripts.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/01/10 21:55:00 JST
+ Tag: blume-20010110-rcc
+ Description:
+ The RCC stuff now seems to work (but only on the x86).
+ This required hacking of the c-calls interface (and -implementation) in
+ MLRISC.
+ Normal compiler users should be unaffected.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/01/09 01:20:00 JST
+ Tag: blume-20010109-rcc
+ Description:
+ This is a fairly big patch, flushing out a large number of pending
+ changes that I made to my development copy over the last couple of days.
+ Of practical relevance at this moment is a workaround for a pickling
+ bug that Allen ran into the other day.  The cause of the bug itself is
+ still unknown and it might be hard to fix it properly, but the
+ workaround has some merits of its own (namely somewhat reducing pickling
+ overhead for certain libraries).  Therefore, I think this solution should
+ be satisfactory at this time.
+ The rest of the changes (i.e., the vast majority) has to do with my
+ ongoing efforts of providing direct support for C function calls from
+ ML.  At the moment there is a new primop "RAW_CCALL", typing magic
+ in types/cproto.sml (invoked from FLINT/trans/translate.sml), a new
+ case in the FLINT CPS datatype (RCC), changes to cps/convert.sml to
+ translate uses of RAW_CCALL into RCC, and changes to mlriscGen.sml to
+ handle RCC.
+ The last part (the changes to mlriscGen.sml) are still known to be
+ wrong on the x86 and not implemented on all other architectures.  But
+ the infrastructure is in place. I had to change a few functor
+ signatures in the backend to be able to route the CCalls interface
+ from MLRISC there, and I had to specialize the mltree type (on the
+ x86) to include the necessary extensions. (The extensions themselves
+ were already there and redy to go in MLRISC/x86).
+ Everything should be very happy as soon as someone helps me with
+ mlriscGen.sml...
+ In any case, nothing of this should matter to anyone as long as the
+ new primop is not being used (which is going to be the case unless you
+ find it where I hid it :). The rest of the compiler is completely
+ unaffected.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2001/01/05 00:30:00 JST
+ Tag: blume-20010105-primops
+ Description:
+ Added some experimental support for work that I am doing right now.
+ These changes mostly concern added primops, but there is also a new
+ experimental C library in the runtime system (but currently not enabled
+ anywhere except on Linux/X86).
+ In the course of adding primops (and playing with them), I discovered that
+ Zhong's INL_PRIM hack (no type info for certain primops) was, in fact, badly
+ broken.  (Zhong was very right he labeled this stuff as "major gross hack".)
+ To recover, I made type information in INL_PRIM mandatory and changed
+ prim.sml as well as built-in.sml accordingly.  The InLine structure now
+ has complete, correct type information (i.e., no bottom types).
+ Since all these changes mean that we need new binfiles, I also bumped the
+ version number to 110.32.1.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/12/30 22:10:00 JST
+ Tag: blume-20001230-various
+ Description:
+ Added proxy libraries for MLRISC and let MLRISC libraries refer
+ to each other using path anchors.  (See CM manual for explanation.)
+ Updated CM documentation.
+ Fixed some bugs in CM.
+ Implemented "proxy" libraries (= syntactic sugar for CM).
+ Added "-quiet" option to makeml and changed runtime system accordingly.
+ Added cleanup handler for exportML to reset timers and compiler stats.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2000/12/22 22:22:58 EST 2000
+ Tag: Release_110_32
+ Description:
+         Infinite precision used throughout MLRISC.
+         see MLRISC/mltree/machine-int.sig
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/12/22 23:16:00 JST
+ Tag: blume-20001222-warn
+ Description:
+ Corrected wording and formatting of some CM warning message which I
+ broke in my previous patch.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/12/22 21:20:00 JST
+ Tag: blume-20001222-anchorenv
+ Description:
+ Fixed CM's handling of anchor environments in connection with CMB.make.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/12/22 13:15:00 JST
+ Tag: blume-20001222-cleanup
+ Description:
+ Removed src/cm/ffi which does not (and did not) belong here.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/12/21 23:55:00 JST
+ Tag: blume-20001221-exn
+ Description:
+ Probably most important: CM no longer silently swallows all exceptions
+ in the compiler.
+ Plus: some other minor CM changes.  For example, CM now reports some
+ sizes for generated binfiles (code, data, envpickle, lambdapickle).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/12/15 00:01:05 JST
+ Tag: blume-20001215-dirtool
+ Description:
+ - "dir" tool added.
+ - improvements and cleanup to Tools structure
+ - documentation updates
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: Thu Dec 14 03:45:24 EST 2000
+ Description:
+ Tag:  leunga-20001214-int-inf
+ Description:
+    In IntInf, added these standard functions, which are missing from our
+ implementation:
+     andb : int * int -> int
+     xorb : int * int -> int
+     orb  : int * int -> int
+     notb : int -> int
+      <<   : int * word -> int
+     ~>>  : int * word -> int
+    Not tested, I hope they are correct.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: Fri Dec  8 19:23:26 EST 2000
+ Description:
+ Tag:  leunga-20001208-nowhere
+ Description:
+   Slight improvements to the 'nowhere' tool to handle OR-patterns,
+ to generate better error messages etc.  Plus a brief manual.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2000/12/08 09:54:02 EST 2000
+ Tag: Release_110_31
+ Description:
+ - Version 110.31
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: Thu Dec  7 22:01:04 EST 2000
+ Tag:  leunga-20001207-cell-monster-hack
+ Description:
+ Major MLRISC internal changes.  Affect all clients.
+ Summary:
+.  Type CELLS.cell = int is now replaced by a datatype.
+     As a result, the old regmap is now gone.  Almost all interfaces
+     in MLRISC change as a consequence.
+.  A new brand version of machine description tool (v3.0) that generates
+     modules expecting the new interface.  The old version is removed.
+.  The RA interface has been further abstracted into two new functors.
+     RISC_RA and X86RA.  These functors have much simpler interfaces.
+     [See also directory MLRISC/demo.]
+.  Some other new source->source code generation tools are available:
+     a. MLRISC/Tools/RewriteGen -- generate rewriters from rules.
+     b. MLRISC/Tools/WhereGen -- expands conditional pattern matching rules.
+        I use this tool to generate the peephole optimizers---with the new
+        cell type changes, peephole rules are becoming difficult to write
+        without conditional pattern matching.
+.  More Intmap -> IntHashTable change.  Previous changes by Matthias didn't
+     cover the entire MLRISC source tree so many things broke.
+.  CM files have been moved to the subdirectory MLRISC/cm.
+     They are moved because there are a lot of them and they clutter up the
+     root dir.
+.  More detailed documentation to come...
+     NOTE: To rebuild from 110.30 (ftp distribution), you'll have to do
+     a makeml -rebuild first.  This is because of other other
+     changes that Matthias has made (see below).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/30 23:12:00 JST
+ Tag: blume-20001130-filereorg
+ Description:
+ Some manual updates and some file reorganizations in CM.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/24 17:45:00 JST
+ Tag: blume-20001124-link
+ Description:
+ Drastically improved link traversal code for the case that the dynamic
+ value was already loaded at bootstrap time.  As a result, CM and CMB
+ now both load blazingly fast -- even on a very slow machine.  Also,
+ memory consumption has been further reduced by this.
+ Warning: The format of the PIDMAP file has changed.  THerefore, to
+ bootstrap you have to do this:
+. Run CMB.make
+. Make a symbolic link for the boot directory:
+      ln -s sml.boot.ARCH-OS xxx
+. "Rebuild" the boot directory:
+      ./makeml -boot xxx -rebuild sml ; rm xxx
+. Boot normally:
+       ./makeml
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/21 21:20:00 JST
+ Tag: blume-20001121-tools
+ Description:
+ Continued hacking on autoloading problem -- with success this time.
+ Also changed tool-plugin mechanism.  See new CM manual.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/19 14:30:00 JST
+ Tag:  blume-20001119-autoload
+ Description:
+ Some hacking to make autoloading faster.  Success for CMB, no success
+ so far for CM.  There is a reduced structure CM' that autoloads faster.
+ (This is a temporary, non-documented hack to be eliminated again when
+ the general problem is solved.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/17 14:10:00 JST
+ Tag: blume-20001117-pickle-lib
+ Description:
+. Eliminated comp-lib.cm
+. Made pickle-lib.cm
+. Eliminated all uses of intset.sml (from comp-lib.cm)
+. Replaced all uses of intmap.{sig,sml} (from comp-lib.cm) with
+    equivalent constructs from smlnj-lib.cm (INtHashTable).
+. Point 4. also goes for those uses of intmap.* in MLRISC.
+    Duplicated intmap modules thrown out.
+. Hunted down all duplicated SCC code and replaced it with
+    equivalent stuff (GraphSCCFn from smlnj-lib.cm).
+. Rewrote Feedback module.
+. Moved sortedlist.sml into viscomp-lib.cm.  Eventually it
+    should be thrown out and equivalent modules from smlnj-lib.cm
+    should be used (IntRedBlackSet, IntListSet, ...).
+ Confirmed that compiler compiles to fixpoint.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/11/10 18:00:00
+ Tag: leunga-20001110-new-x86-fp
+ A new x86 floating point code generator has been added.
+ By default this is turned off.  To turn this on, do:
+     CM.autoload "$smlnj/compiler.cm";
+     Compiler.Control.MLRISC.getFlag "x86-fast-fp" := true;
+ Changes:
+.  Changed FTAN to FPTAN so that the assembly output is correct.
+.  Changed the extension callback for FTANGENT to generate:
+           fptan
+           fstp  %st(0)
+     instead of
+           fptan
+           fstpl ftempmem
+.  Numerous assembly fixes for x86.
+.  Cleaned up the machine code output module x86/x86MC.sml and added
+     support for a whole bunch of instructions and addressing modes:
+       fadd/fsub/fsubr/fmul/fdiv/fdivr  %st, %st(n)
+       faddp/fsubp/fsubrp/fmulp/fdivp/fdivrp  %st, %st(n)
+       fadd/fsub/fsubr/fmul/fdiv/fdivr  %st(n), %st
+       fiadd/fisub/fisubr/fimul/fidiv/fidivr mem
+       fxch %st(n)
+       fld %st(n)
+       fst %st(n)
+       fst mem
+       fstp %st(n)
+       fucom %st(n)
+       fucomp %st(n)
+     All these are now generated when the fast fp mode is turned on.
+.  Removed the dedicated registers %st(0), ..., %st(7) from X86CpsRegs
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/09 11:20:00 JST
+ Tag: blume-20001109-scc
+ Description:
+ Eliminated some code duplication:
+. Added "where" clause to GraphSCCFn in SML/NJ Library.
+    (Otherwise the functor is useless.)
+. Used GraphSCCFn where SCCUtilFun was used previously.
+. Got rid of SCCUtilFun (in comp-lib.cm).
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2000/11/06 09:02:21 EST 2000
+ Tag: Release_110_30
+ Description:
+ - Version 110.30
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/04 14:45:00
+ Tag: blume-20001104-mlbuild
+ Description:
+ - Made ml-build faster on startup.
+ - Documentation fixes.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/11/02 17:00:00 JST
+ Tag: blume-20001102-condcomp
+ Description:
+ - Small tweaks to pickler -- new BOOTFILES!
+ - Version bumped to 110.29.2.
+ - Added conditional compilation facility to init.cmi (see comment there).
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/10/23 19:31:00
+ Tag: leunga-20001023-demo-ra
+. Minor RA changes that improves spilling on x86 (affects Moby and C-- only)
+. Test programs for the graph library updated
+. Some new MLRISC demo programs added
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/08/31 22:15:00 JST
+ Tag: blume-20001017-errmsg
+ Description:
+ More error message grief: Where there used to be no messages, there
+ now were some that had bogus error regions.  Fixed.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/08/31 17:30:00 JST
+ Tag: blume-20001017-v110p29p1
+ Description:
+ I made a version 110.29.1 with new bootfiles.
+ Changes:  Modified pickler/unpickler for faster and leaner unpickling.
+           CM documentation changes and a small bugfix in CM's error reporting.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2000/09/27 14:42:35 EDT
+ Tag: george-20000927-nodestatus
+ Description:
+ Changed the type of the nodestatus, so that:
+         SPILLED(~1)             is now SPILLED
+         SPILLED(m) where m>=0   is now MEMREG(m)
+         SPILLED(s) where s<~1   is now SPILL_LOC(~s)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/09/07 14:45:00 JST
+ Tag: blume-20000907-cmerrmsg
+ Description:
+ Small tweak to CM to avoid getting ML syntax error messages twice.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/08/31 18:00:00 JST
+ Tag: blume-20000831-cvsbootfiles
+ Description:
+ New URL for boot files (because the 110.29 files on the BL server do
+ now work correctly with my updated install scripts for yacc and lex).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/08/08 12:33:00 JST
+ Tag: blume-20000808-manual
+ Description:
+ Tiny update to CM manual.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/08/7 19:31:00
+ Tag: leunga-20000807-a-whole-bunch-of-stuff
+   Moby, C--, SSA, x86, machine descriptions etc.  Should only affect C--
+ and Mobdy.
+.  x86
+    a.  Fixes to peephole module by John and Dan.
+    b.  Assembly fix to SETcc by Allen.
+    c.  Fix to c-call by John.
+    d.  Fix to spilling by John.  (This one deals with the missing FSTPT case)
+    e.  Instruction selection optimization to SETcc as suggested by John.
+        For example,
+         MV(32, x, COND(32, CMP(32, LT, a, b), LI 1, LI 0))
+        should generate:
+         MOVL a, x
+         SUBL b, x
+         SHRL 31, x
+.  IR stuff
+      A bunch of new DJ-graph related algorithms added.  These
+      speed up SSA construction.
+.  SSA + Scheduling
+      Added code for SSA and scheduling to the repository
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2000/07/27 11:53:14 EDT
+ Tag: lal-20000727-linux-ppc
+ Description:
+  Made changes to support Linux PPC.
+  p.s. I have confirmation that the 110.29 boot files work fine.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/07/27 17:40:00 JST
+ Tag: blume-20000727-scripts
+ Description:
+ !!!! WARNING !!!!
+ You must recompile the runtime system!
+ !!!! WARNING !!!!
+ This is basically another round of script-enhancements:
+. sml, ml-build, and ml-makedepend accept options -D and -U to define
+    and undefine CM preprocessor symbols.
+. ml-build avoids generating a new heap image if it finds that the
+    existing one is still ok.  (The condition is that no ML file had to
+    be recompiled and all ML files are found to be older that the heap
+    file.)
+    To make this work smoothly, I also hacked the runtime system as
+    well as SMLofNJ.SysInfo to get access to the heap image suffix
+    (.sparc-solaris, ...) that is currently being used.
+    Moreover, the signature of CM.mk_standalone has changed.  See the
+    CM manual.
+. ml-makedepend accepts additional options -n, -a, and -o.  (See the
+    CM manual for details.)
+. More CM manual updates:
+     - all of the above has been documented.
+     - there is now a section describing the (CM-related) command line
+       arguments that are accepted by the "sml" command
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/07/25 16:20:00 JST
+ Tag: blume-20000725-makedepend
+ Description:
+ Added a script called ml-makedepend.  This can be used in makefiles
+ for Unix' make in a way very similar to the "makedepend" command for
+ C.
+ The script internally uses function CM.sources.
+ Synopsis:
+     ml-makedepend [-f makefile] cmfile targetname
+ The default for the makefile is "makefile" (or "Makefile" should
+ "makefile" not exist).
+ ml-makedepend adds a cmfile/targetname-specific section to this
+ makefile (after removing the previous version of this section).  The
+ section contains a single dependency specification with targetname on
+ the LHS (targetname is an arbitrary name), and a list of files derived
+ from the cmfile on the RHS.  Some of the files on the RHS are
+ ARCH/OPSYS-specific.  Therefore, ml-makedepend inserts references to
+ "make" variables $(ARCH) and $(OPSYS) in place of the corresponding
+ path names.  The makefile writer is responsible for making sure that
+ these variables have correct at the time "make" is invoked.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/07/22 23:30:00 JST
+ Tag: blume-20000722-urlupdate
+ Description:
+ Changed BOOT and config/srcarchiveurl to point to BL server:
+     ftp://ftp.research.bell-labs.com/dist/smlnj/working/110.29/
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/07/18 18:00:00 JST
+ Tag: blume-20000718-Version_110_29
+ Description:
+. Updated src/compiler/TopLevel/main/version.sml to version 110.29
+. Updated config/version to 110.29
+. Updated config/srcarchiveurl
+. New boot files!
+    ftp://ftp.cs.princeton.edu/pub/people/blume/sml/110.29-autofetch
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/07/11 13:58:00 JST
+ Tag: blume-20000711-doctypo
+ Description:
+ Fixed a few typos in CM manual.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/06/15 00:38:00
+ Tag: leunga-20000704-sparc-x86
+. x86 peephole improvement sp += k; sp -= k => nop  [from John]
+. fix to x86 RET bug [found by Dan Grossman]
+. sparc assembly bug fix for ticc instructions [found by Fermin]
+    Affects c-- and moby only
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/07/04 15:26:00
+ Tag: blume-20000704-trigger
+ Description:
+. Improvements to CM manual.
+. SMLofNJ.Internals.BTrace.trigger reinstated as an alternative way
+    of getting a back-trace.  The function, when called, raises an
+    internal exception which explicitly carries the full back-trace history,
+    so it is unaffected by any intervening handle-raise pairs ("trivial"
+    or not).  The interactive loop will print that history once it arrives
+    at top level.
+    Short of having all exceptions implicitly carry the full history, the
+    recommended way of using this facility is:
+      - compile your program with instrumentation "on"
+      - run it, when it raises an exception, look at the history
+      - if the history is "cut off" because of some handler, go and modify
+        your program so that it explicitly calls BTrace.trigger
+      - recompile (still instrumented), and rerun; look at the full history
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/07/03 15:36:00 JST
+ Tag: blume-20000702-manual
+ Description:
+ Small corrections and updates to CM manual.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/29 16:04:00 JST
+ Tag: blume-20000629-yacctool
+ Description:
+ Changes:
+. Class "mlyacc" now takes separate arguments to pass options to
+    generated .sml- and .sig-files independently.
+. Corresponding CM manual updates.
+. BTrace module now also reports call sites.  (However, for loop clusters
+    it only shows from where the cluster was entered.)  There are associated
+    modifications to core.sml, internals.{sig,sml}, btrace.sml, and btimp.sml.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/27 16:51:00 JST
+ Tag: blume-20000627-noweb
+ Description:
+ Changes:
+. Implemented "subdir" and "witness" options for noweb tool.
+     This caused some slight internal changes in CM's tool implementation.
+. Fixed bug in "tool plugin" mechanism.  This is essentially cleaning
+     some remaining issues from earlier path anchor changes.
+. Updated CM manual accordingly.
+. Changed implementation of back-tracing so that I now consider it
+     ready for prime-time.
+     In particular, you don't have to explicitly trigger the back-trace
+     anymore.  Instead, if you are running BTrace-instrumented code and
+     there is an uncaught exception (regardless of whether or not it was
+     raised in instrumented code), the top-level evalloop will print
+     the back-trace.
+     Features:
+       - Instrumented and uninstrumented code work together seemlessly.
+         (Of course, uninstrumented code is never mentioned in actual
+          back-traces.)
+       - Asymptotic time- and space-complexity of instrumented code is
+         equal to that of uninstrumented code.  (This means that
+         tail-recursion is preserved by the instrumentation phase.)
+       - Modules whose code has been instrumented in different sessions
+         work together without problem.
+       - There is no penalty whatsoever on uninstrumented code.
+       - There is no penalty on "raise" expressions, even in
+         instrumented code.
+     A potential bug (or perhaps it is a feature, too):
+       A back-trace reaches no further than the outermost instrumented
+       non-trivial "raise".  Here, a "trivial" raise is one that is the
+       sole RHS of a "handle" rule.  Thus, back-traces reach trough
+            <exp> handle e => raise e
+       and even
+            <exp> handle Foo => raise Bar
+       and, of course, through
+            <exp> handle Foo => ...
+      if the exception was not Foo.
+      Back-traces always reach right through any un-instrumented code
+      including any of its "handle" expressions, trivial or not.
+    To try this out, do the following:
+      - Erase all existing binfiles for your program.
+        (You may keep binfiles for those modules where you think you
+         definitely don't need back-tracing.)
+      - Turn on back-trace instrumentation:
+           SMLofNJ.Internals.BTrace.mode (SOME true);
+      - Recompile your program.  (I.e., run "CM.make" or "use".)
+      - You may now turn instrumentation off again (if you want):
+           SMLofNJ.Internals.BTrace.mode (SOME false);
+      - Run your program as usual.  If it raises an exception that
+        reaches the interactive toplevel, then a back-trace will
+        automatically be printed.  After that, the toplevel loop
+        will print the exception history as usual.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/26 09:56:46 JST
+ Tag: blume-20000626-setup
+ Description:
+ CM: - setup-parameter to "sml" added; this can be used to run arbitrary
+       ML code before and after compiling a file (e.g., to set compiler
+       flags)
+ Compiler: - improved btrace API (in core.sml, internals.{sig,sml})
+           - associated changes to btrace.sml (BTrace instrumentation pass)
+           - cleaner implementation of btimp.sml (BTrace tracing and report
+             module)
+ CM manual: * new path encoding documented
+            * description of setup-parameter to "sml" added
+ The biggest user-visible change to back-tracing is that it is no
+ longer necessary to compile all traced modules within the same
+ session.  (This was a real limitation.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/24 12:40:00 JST
+ Tag: blume-20000624-startup
+ Description:
+ Fixes startup slowdown problem.  (I was calling SrcPath.sync a _tad_
+ bit too often -- to put it mildly. :)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/23 18:20:00 JST
+ Tag: blume-20000623-btrace
+ Description:
+ This updates adds a backtrace facility to aid programmers in debugging
+ their programs.  This involves the following changes:
+. Module system/smlnj/init/core.sml (structure _Core) now has hooks for
+    keeping track of the current call stack.  When programs are compiled
+    in a special mode, the compiler will insert calls to these hooks
+    into the user program.
+    "Hook" means that it is possible for different implementations of
+    back-tracing to register themselves (at different times).
+. compiler/MiscUtil/profile/btrace.sml implements the annotation phase
+    as an Absyn.dec->Absyn.dec rewrite.  Normally this phase is turned off.
+    It can be turned on using this call:
+      SMLofNJ.Internals.BTrace.mode (SOME true);
+    Turning it off again:
+      SMLofNJ.Internals.BTrace.mode (SOME false);
+    Querying the current status:
+      SMLofNJ.Internals.BTrace.mode NONE;
+    Annotated programs are about twice as big as normal ones, and they
+    run a factor of 2 to 4 slower with a dummy back-trace plugin (one
+    where all hooks do nothing).  The slowdown with a plugin that is
+    actually useful (such as the one supplied by default) is even greater,
+    but in the case of the default plugin it is still only an constant
+    factor (amortized).
+. system/Basis/Implementation/NJ/internals.{sig,sml} have been augmented
+    with a sub-structure BTrace for controlling back-tracing.  In particular,
+    the above-mentioned function "mode" controls whether the annotation
+    phase is invoked by the compiler.  Another important function is
+    "trigger": when called it aborts the current execution and causes
+    the top-level loop to print a full back-trace.
+. compiler/MiscUtil/profile/btimp.sml is the current default plugin
+    for back-tracing.  It keeps track of the dynamic call stack and in
+    addition to that it keeps a partial history at each "level" of that
+    stack.  For example, if a tail-calls b, b tail-calls c, and c tail-calls
+    d and b (at separate times, dynamically), then the report will show:
+    GOTO   d
+          /c
+    GOTO  \b
+    CALL   a
+    This shows that there was an initial non-tail call of a, then a
+    tail-call to b or c, looping behavior in a cluster of functions that
+    consist of b and c, and then a goto from that cluster (i.e., either from
+    b or from c) to d.
+    Note that (depending on the user program) the amount of information
+    that the back-trace module has to keep track of at each level is bounded
+    by a constant.  Thus, the whole implementation has the same asymptotical
+    complexity as the original program (both in space and in time).
+. compiler/TopLevel/interact/evalloop.sml has been modified to
+    handle the special exception SMLofNJ.Internals.BTrace.BTrace
+    which is raised by the "trigger" function mentioned above.
+ Notes on usage:
+ - Annotated code works well together with unannotated code:
+ Unannotated calls simply do not show up at all in the backtrace.
+ - It is not a good idea to let modules that were annotated during
+ different sessions run at the same time.  This is because the compiler
+ chooses small integers to identify individual functions, and there
+ will be clashes if different modules were compiled in separate sessions.
+ (Nothing will crash, and you will even be told about the clashes, but
+ back-trace information will in general not be useful.)
+ - Back-tracing can be confused by callcc and capture.
+ - The only way of getting a back-trace right now is to explicitly
+ invoke the "trigger" function from your user program.  Eventually, we
+ should make every exception carry back-trace information (if
+ available).  But since this creates more overhead at "raise"-time
+ (similar to the current exnHistory overhead), I have not yet
+ implemented this.  (The implementation will be rather easy.)  With
+ exceptions carrying back-trace information, this facility will be even
+ more useful because users don't need to modify their programs...
+ - While it is possible to compile the compiler with back-trace
+ annotations turned on (I did it to get some confidence in
+ correctness), you must make absolutely sure that core.sml and
+ btimp.sml are compiled WITHOUT annotation!  (core.sml cannot actually
+ be compiled with annotation because there is no core access yet, but
+ if you compile btimp.sml with annotation, then the system will go into
+ an infinite recursion and crash.)
+ Since CM currently does not know about BTrace, the only way to turn
+ annotations on and off for different modules of the compiler is to
+ interrupt CMB.make, change the settings, and re-invoke it.  Of course,
+ this is awkward and clumsy.
+ Sample sessions:
+ Standard ML of New Jersey v110.28.1 [FLINT v1.5], June 5, 2000
+ - SMLofNJ.Internals.BTrace.mode (SOME true);
+ [autoloading]
+ [autoloading done]
+ val it = false : bool
+ - structure X = struct
+ -     fun main n = let
+ -         fun a (x, 0) = d x
+ -           | a (x, n) = b (x, n - 1)
+ -         and b (x, n) = c (x, n)
+ -         and c (x, n) = a (x, n)
+ -         and d x = e (x, 3)
+ -         and e (x, 0) = f x
+ -           | e (x, n) = e (x, n - 1)
+ -         and f 0 = SMLofNJ.Internals.BTrace.trigger ()
+ -           | f n = n * g (n - 1)
+ -         and g n = a (n, 3)
+ -     in
+ -         f n
+ -     end
+ - end;
+ structure X : sig val main : int -> int end
+ - X.main 3;
+ *** BACK-TRACE ***
+ GOTO   stdIn:4.2-13.20: X.main[2].f
+ GOTO-( stdIn:4.2-13.20: X.main[2].e
+ GOTO   stdIn:4.2-13.20: X.main[2].d
+      / stdIn:4.2-13.20: X.main[2].a
+      | stdIn:4.2-13.20: X.main[2].b
+ GOTO-\ stdIn:4.2-13.20: X.main[2].c
+ CALL   stdIn:4.2-13.20: X.main[2].g
+ GOTO   stdIn:4.2-13.20: X.main[2].f
+ GOTO-( stdIn:4.2-13.20: X.main[2].e
+ GOTO   stdIn:4.2-13.20: X.main[2].d
+      / stdIn:4.2-13.20: X.main[2].a
+      | stdIn:4.2-13.20: X.main[2].b
+ GOTO-\ stdIn:4.2-13.20: X.main[2].c
+ CALL   stdIn:4.2-13.20: X.main[2].g
+ GOTO   stdIn:4.2-13.20: X.main[2].f
+ GOTO-( stdIn:4.2-13.20: X.main[2].e
+ GOTO   stdIn:4.2-13.20: X.main[2].d
+      / stdIn:4.2-13.20: X.main[2].a
+      | stdIn:4.2-13.20: X.main[2].b
+ GOTO-\ stdIn:4.2-13.20: X.main[2].c
+ CALL   stdIn:4.2-13.20: X.main[2].g
+ GOTO   stdIn:4.2-13.20: X.main[2].f
+ CALL   stdIn:2.15-17.4: X.main[2]
+ -
+ (Note that because of a FLINt bug the above code currently does not
+ compile without BTrace turned on.)
+ Here is another example, using my modified Tiger compiler:
+ Standard ML of New Jersey v110.28.1 [FLINT v1.5], June 5, 2000
+ - SMLofNJ.Internals.BTrace.mode (SOME true);
+ [autoloading]
+ [autoloading done]
+ val it = false : bool
+ - CM.make "sources.cm";
+ [autoloading]
+ ...
+ [autoloading done]
+ [scanning sources.cm]
+ [parsing (sources.cm):parse.sml]
+ [creating directory CM/SKEL ...]
+ [parsing (sources.cm):tiger.lex.sml]
+ ...
+ [wrote CM/sparc-unix/semant.sml]
+ [compiling (sources.cm):main.sml]
+ [wrote CM/sparc-unix/main.sml]
+ [New bindings added.]
+ val it = true : bool
+ - Main.compile ("../testcases/merge.tig", "foo.out");
+ *** BACK-TRACE ***
+ CALL   lib/semant.sml:99.2-396.21: SemantFun[2].transExp.trvar
+ CALL   lib/semant.sml:99.2-396.21: SemantFun[2].transExp.trexp
+ CALL   lib/semant.sml:289.3-295.22: SemantFun[2].transExp.trexp.check[2]
+ GOTO   lib/semant.sml:289.3-295.22: SemantFun[2].transExp.trexp.check[2]
+ CALL   lib/semant.sml:99.2-396.21: SemantFun[2].transExp.trexp
+ CALL   lib/semant.sml:99.2-396.21: SemantFun[2].transExp.trexp
+ CALL   lib/semant.sml:488.3-505.6: SemantFun[2].transDec.trdec[2].transBody[2]
+      / lib/semant.sml:411.65-543.8: SemantFun[2].transDec
+ CALL-\ lib/semant.sml:413.2-540.9: SemantFun[2].transDec.trdec[2]
+ CALL   lib/semant.sml:99.2-396.21: SemantFun[2].transExp.trexp
+ CALL   lib/semant.sml:8.52-558.4: SemantFun[2].transProg[2]
+ CALL   main.sml:1.18-118.4: Main.compile[2]
+ -
+ ----------------------------------------------------------------------
+ Name: Matthias Blumen
+ Date: 2000/06/21 18:00:00 JST
+ Tag: blume-20000621-manual
+ Description:
+ CM manual update: Path environments documented.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/19 13:40:00
+ Tag: blume-20000619-manual
+ Description:
+ CM manual and system/README update.  This only covers the fact that
+ there are no more implicit anchors.  (Path environments and the "bind"
+ option to "cm" have yet to be documented.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/19 11:05:00 JST
+ Tag: blume-20000619-chdir-bugfix
+ Description:
+ Fixed a bug in new SrcPath module that sometimes led to a bad chDir call.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/18 22:00:10 JST
+ Tag: blume-20000618-implicit-anchors-really-gone
+ Description:
+ I updates the previous HISTORY entry where I forgot to mention that
+ implicit anchors are no longer with us.
+ The current update also gets rid of the (now useless) controller
+ CM.Control.implicit_anchors.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/16 17:30:00 JST
+ Tag: blume-20000616-anchorenv
+ Description:
+ This patch implements the long anticipated (just kidding :) "anchor
+ environment" mechanism.  In the course of doing this, I also
+ re-implemented CM's internal "SrcPath" module from scratch.  The new
+ one should be more robust in certain boundary cases.  In any case, it
+ is a lot cleaner than its predecessor (IMHO).
+ This time, although there is yet another boot file format change, I
+ kept the unpickler backward-compatible.  As a result, no new bootfiles
+ are necessary and bootstrapping is straightforward.  (You cannot read
+ new bootfiles into an old system, but the other way around is no
+ problem.)
+ Visible changes:
+ ** 0. Implicit path anchors (without the leading $-symbol) are no
+ longer recognized at all. This means that such path names are not
+ illegal either.  For example, the name basis.cm simply refers to a
+ local file called "basis.cm" (i.e, the name is an ordinary path
+ relative to .cm-files directory).  Or, to put it differently, only
+ names that start with $ are anchored paths.
+ ** 1. The $<singlearc> abbreviation for $/<singlearc> has finally
+ vanished.
+ John (Reppy) had critizised this as soon as I originally proposed and
+ implemented it, but at that time I did not really deeply believe
+ him. :) Now I came full-circle because I need the $<singlearc> syntax
+ in another place where it cannot be seen as an abbreviation for
+ $/<singlearc>.  To avoid the confusion, $<singlearc> now means what it
+ seems to mean (i.e., it "expands" into the corresponding anchor
+ value).
+ However, when paths are used as members in CM description files, it
+ continues to be true that there must be at least another arc after the
+ anchor.  This is now enforced separately during semantic analysis
+ (i.e., from a lexical/syntactical point of view, the notation is ok.)
+ ** 2. The "cm" class now accepts an option "bind".  The option's value
+ is a sub-option list of precisely two items -- one labeled "anchor"
+ and the other one labeled "value".  As you might expect, "anchor" is
+ used to specify an anchor name to be bound, and "value" specifies what
+ the anchor is being bound to.
+ The value must be a directory name and can be given in either standard
+ syntax (including the possibility that it is itself an anchored path)
+ or native syntax.
+ Examples:
+    foo.cm (bind:(anchor:bar value:$mystuff/bar))
+    lib.cm (bind:(anchor:a value:"H:\\x\\y\\z"))  (* only works under windows *)
+ and so on.
+ The meaning of this is that the .cm-file will be processed with an
+ augmented anchor environment where the given anchor(s) is/are bound to
+ the given values(s).
+ The rationale for having this feature is this: Suppose you are trying
+ to use two different (already stable) libraries a.cm and b.cm (that
+ you perhaps didn't write yourself).  Further, suppose each of these
+ two libraries internally uses its own auxiliary library $aux/lib.cm.
+ Normally you would now have a problem because the anchor "lib" can not
+ be bound to more than one value globally.  Therefore, the project that
+ uses both a.cm and b.cm must locally redirect the anchor to some other
+ place:
+    a.cm (bind:(anchor:lib value:/usr/lib/smlnj/a-stuff))
+    b.cm (bind:(anchor:lib value:/usr/lib/smlnj/b-stuff))
+ This hard-wires $lib/aux.cm to /usr/lib/smlnj/a-stuff/aux.cm or
+ /usr/lib/smlnj/b-stuff/aux.cm, respectively.
+ Hard-wiring path names is a bit inflexible (and CM will verbosely warn
+ you when you do so at the time of CM.stabilize).  Therefore, you can
+ also use an anchored path as the value:
+   a.cm (bind:(anchor:lib value:$a-lib))
+   b.cm (bind:(anchor:lib value:$b-lib))
+ Now you can globally configure (using the usual CM.Anchor.anchor or
+ pathconfig machinery) bindings for "a-lib" and "b-lib".  Since "lib"
+ itself is always locally bound, setting it globally is no longer
+ meaningful or necessary (but it does not hurt either).  In fact, "lib"
+ can still be used as a global anchor for separate purposes.  As a
+ matter of fact, one can locally define "lib" in terms of a global
+ "lib":
+   a.cm (bind:(anchor:lib value:$lib/a))
+   b.cm (bind:(anchor:lib value:$lib/b))
+ ** 3: The encoding of path names has changed.  This affects the way
+ path names are shown in CM's progress report and also the internal
+ protocol encoding used for parallel make.
+ The encoding now uses one or more ':'-separated segments.  Each
+ segments corresponds to a file that has been specified relative to the
+ file given by its preceding segment.  The first segment is either
+ relative to the CWD, absolute, or anchored.  Each segment itself is
+ basically a Unix pathname; all segments but the first are relative.
+ Example:
+    $foo/bar/baz.cm:a/b/c.sml
+ This path denotes the file bar/a/b/c.sml relative to the directory
+ denoted by anchor "foo".  Notice that the encoding also includes
+ baz.cm which is the .cm-file that listed a/b/c.sml.  As usual, such
+ paths are resolved relative to the .cm-files directory, so baz.cm must
+ be ignored to get the "real" pathname.
+ To make this fact more obvious, CM puts the names of such "virtual
+ arcs" into parentheses when they appear in progress reports. (No
+ parentheses will appear in the internal protocol encoding.)  Thus,
+ what you really see is:
+   $foo/bar/(baz.cm):a/b/c.sml
+ I find this notation to be much more informative than before.
+ Another new feature of the encoding is that special characters
+ including parentheses, colons, (back)slashes, and white space are
+ written as \ddd (where ddd is the decimal encoding of the character).
+ *** The CM manual still needs to be updated.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/06/15 00:38:00
+ Tag: leunga-20000615-x86-peephole
+ x86 Peephole fix by Fermin.  Affects c-- and moby only.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/12 11:40:00
+ Tag: blume-20000612-parmakefix
+ Description:
+ More cleanup after changing the file naming scheme: This time I
+ repaired the parallel make mechanism for CMB.make which I broke earlier.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/06/09 01:25:00
+ Tag: leunga-20000609-various
+ None of these things should affect normal SML/NJ operations
+. Peephole improvements provided by Fermin (c--)
+. New annotation DEFUSE for adding extra dependence (moby)
+. New X86 LOCK instructions (moby)
+. New machine description language for reservation tables (scheduling)
+. Fixes to various optimization/analysis modules (branch chaining, dominator
+    trees etc.)
+. I've changed the CM files so that they can work with versions
+.0.6, 110.25 and 110.28
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/09 12:40:00
+ Tag: blume-20000609-log
+ Description:
+ - Removed all(?) remaining RCS Log entries from sources.
+ - Fixed bug in ml-yacc and ml-lex sources (use explicit anchors for
+   anchored paths).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/07 17:00:00 JST
+ Tag: blume-20000607-no-implicit-anchors
+ Description:
+. This update changes the default setting for
+ CM.Control.implicit_anchors from true to false.  This means that
+ implicit anchors are no longer permitted by default.  I also tried to
+ make sure that nothing else still relies on implicit anchors.
+ (This is the next step on the schedule towards a CM that does not even
+ have the notion of implicit anchors anymore.)
+. More CM manual updates.
+. I managed to track down and fix the pickling bug I mentioned last
+ time.  Because of the previously existing workaround, this entails no
+ immediate practical changes.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/06/06 11:15:00 JST
+ Tag: blume-20000606-lazierpickle
+ Description:
+ !!!! NEW BOOT FILES !!!!
+ * The main purpose of this update is to make library pickles lazier in
+ order to reduce the initial space penalty for autoloading a library.
+ As a result, it is now possible to have $smlnj/compiler.cm
+ pre-registered.  This should take care of the many complaints or
+ inquiries about missing structure Compiler.  This required changes to
+ CM's internal data structures and small tweaks to some algorithms.
+ As a neat additional effect, it is no longer necessary (for the sake
+ of lean heap image files) to distinguish between a "minimal" CM and a
+ "full" CM.  Now, there is only one CM (i.e., the "full" version:
+ $smlnj/cm.cm aka $smlnj/cm/full.cm), and it is always available at the
+ interactive top level. ($smlnj/cm/minimal.cm is gone.)
+ To make the life of compiler-hackers easier, "makeml" now also
+ pre-registers $smlnj/cmb.cm (aka $smlnj/cmb/current.cm).  In other
+ words, after you bootstrap a new sml for the first time, you will not
+ have to autoload $smlnj/cmb.cm again afterwards.  (The first time
+ around you will still have to do it, though.)
+ * A second change consists of major updates to the CM manual.  There
+ are now several appendices with summary information and also a full
+ specification of the CM description file syntax.
+ * In directory src/system I added the script "allcross".  This script
+ invokes sml and cross-compiles the compiler for all supported
+ architectures.  (Useful when providing a new set of boot files.)
+ * There seems to be a latent bug in my "lazy pickles" mechanism.  I
+ added a small tweak to pickle-util.sml to work around this problem,
+ but it is not a proper fix yet.  I will investigate further.  (The
+ effect of the bug was an inflation of library pickle size.)
+ * Version number increased to 110.28.1 (to avoid compatibility problems).
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/05/25 17:28 EDT
+ Tag: leunga-20000525-ra
+ Description:
+   Fixed a bug in freezing phase of the register allocator.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/05/15 22:53 EDT
+ Tag: leunga-20000515-alpha-x86-ra
+ Description:
+. Alpha
+       Slight cleanup.  Removed the instruction SGNXL
+. X86
+       Added the following instructions to the instruction set:
+         ROLx, RORx,
+         BTx, BTSx, BTLx, BTRx,
+         XCHGx, and variants with the LOCK prefix
+. Register Allocation
+       The module ra-rewrite-with-renaming has been improved.
+   These have no effect on SML/NJ.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/05/15 16:20:00 JST
+ Tag: blume-20000515-lightrebuild
+ Description:
+. I added an alternative to "-rebuild" to "makeml".  The difference is
+    that prior to calling CMB.make' the CM-variable "LIGHT" will be
+    defined.  In effect, the command will not build any cross-compiler
+    backends and therefore finish more quickly.
+    The "fixpt" script also takes a "-light" switch to be able to use
+    this new facility while compiling for a fixpoint.
+. I replaced all mentions of anchored paths in group owner specifications
+    with simple relative paths (usually starting with "..").
+    The rationale is that a library's internal workings should not be
+    compromised by the lack of some anchor.  (An anchor is necessary
+    for someone who wants to refer to the library by an anchored path,
+    but it should not be necessary to build the same library in the first
+    place.)
+. I changed the way CM's tool mechanism determines the shell command
+    string used for things like ml-yacc etc. so that it does not break
+    when CM.Control.implicit_anchors is turned off.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/05/12 18:20:00 JST
+ Tag: blume-20000512-ml-build
+ Description:
+ Fixed a bug in config/_ml-build that prevented ml-yacc and ml-lex from
+ getting installed properly (by config/install.sh).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/05/12 17:30:00 JST
+ Tag: blume-20000512-anchors
+ Description:
+ !!! NEW BOOT FILES !!!
+ This change is in preparation of fading out support for "implicitly
+ anchored path names".  I went through all sources and used the
+ explicit (and relatively new) $-notation.  See system/README and the
+ CM manual for more info on this.
+ I also modified the anchoring scheme for some things such as "smlnj",
+ "MLRISC", "cm", etc. to take advantage of the fact that explicit
+ anchors are more expressive: anchor name and first arc do not have to
+ coincide.  This entails the following user-visible change:
+ You have to write $smlnj/foo/bar instead of smlnj/foo/bar.  In
+ particular, when you fire up sml with a command-line argument, say,
+ e.g.:
+    sml '$smlnj/cmb.cm'
+ At the ML toplevel prompt:
+    CM.autoload "$smlnj/cmb.cm";
+ There is also a new controller in CM.Control that can be used to turn
+ off all remaining support for implicit anchors by saying:
+     CM.autoload "$smlnj/
+     #set CM.Control.implicit_anchors false;
+ This causes CM to reject implicitly anchored paths.  This is (for the
+ time being) less permissive than the "final" version where there will
+ be no more such implicit anchors and relative paths will be just that:
+ relative.
+ The next step (version after next version?) will be to make the
+ default for CM.Control.implicit_anchors false.  After the dust has
+ settled, I can then produce the "final" version of this...
+ Note: Since bootstrapping is a bit tricky, I provided new boot files.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/05/11 16:30:00 JST
+ Tag: blume-20000511-sources
+ Description:
+ The main change is that I added function CM.sources as a generalized
+ version of the earlier CM.makedepend.  This entails the following
+ additional changes:
+   - CM.makedepend has been dropped.
+   - CM manual has been updated.
+   - TOOLS signature and API have been changed.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/05/10 21:17 EDT
+ Tag: leunga-20000510-moby-c--ssa
+ Description:
+   Various bug fixes and new features for C--, Moby and MLRISC optimizations.
+ None of these affect SML/NJ.
+. Register Allocation
+     a. A new ra spilling module (ra/ra-spill-with-renaming) is implemented.
+        This module tries to remove local (i.e. basic block level) redundancies
+        during spilling.
+     b. A new framework for performing region based register allocation.
+        Not yet entirely functional.
+. X86
+    a. DefUse for POP was missing the stack pointer [found by Lal]
+    b. Reload for CALL was incorrect in X86Spill [found by John]
+    c. Various fixes in X86Spill so that it can be used correctly for
+       the new spilling module.
+. SSA/IR
+    a. New module ir/dj-dataflow.sml implements elimination based
+       data flow analysis.
+. MLRiscGen
+    a. Fix for gc type annotation
+. MDGen
+    Various fixes for machine description -> ml code translation.  For ssa
+    only.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/05/08 22:17 EDT
+ Tag: leunga-20000508-labexp
+ Description:
+   Fermin has found a few assembly problems with constant expressions
+   generated in LabelExp.  Mostly, the problems involve extra parentheses,
+   which choke on dumb assemblers.  This is his fix.
+ ----------------------------------------------------------------------
+ Name: Dave MacQueen
+ Date: 2000/04/09 14:00 EDT
+ Tag: dbm-20000502-Version_110_28
+ Description:
+. Updated src/compiler/TopLevel/main/version.sml to version 110.28
+. Updated config/version to 110.28
+. Updated config/srcarchiveurl
+. New boot files!
+    ftp://ftp.research.bell-labs.com/dist/smlnj/working/110.28/
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/05/01 19:05:00 JST
+ Tag: blume-20000501-noweb
+ Description:
+ A new noweb tool has been added.  The existing system is entirely
+ unaffected by this, but some CM users have asked for renewed noweb
+ support.  Everything is documented in the CM manual.
+ New (plugin) libraries:
+    noweb-tool.cm
+    nw-ext.cm
+ ----------------------------------------------------------------------
+ Name: Dave MacQueen
+ Date: 2000/04/30 12:40PM EDT
+ Tag: dbm-20000430-bug_fixes
+ Description:
+. Fix for bug 1498
+    smlnj/src/system/Basis/Implementation/Unsafe/object.sig
+    smlnj/src/system/Basis/Implementation/Unsafe/object.sml
+      added toRealArray function
+    smlnj/src/compiler/MiscUtil/print/ppobj.sml
+      added check for tag Obj.RealArray to array printing case in ppObj
+. Fix for bug 1510
+    smlnj/src/compiler/Semant/types/typesutil.sml
+      fixed definition of dummyargs (used by equalTycon) so that
+      dummy args are distinct types
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/04/30 01:00:00 JST
+ Tag: blume-20000430-versions
+ Description:
+. CM version numbering added.  This is an implementation of Lal's
+    proposal for adding version numbers and version checking to .cm
+    files.  Lal said that his proposal was just that -- a proposal.
+    For the time being I went ahead and implemented it so that people
+    can comment on it.  Everything is completely backward-compatible
+    (except for the stable library format, i.e., new bootfiles!).
+    As usual, see the CM manual for details.
+. An alternative syntax for anchored paths has been implemented.
+    Dave has recently voiced the same concerns that I had when I did
+    this, so there should be some support.  My take is that eventually
+    I will let support for the current syntax (where anchors are
+    "implicit") fade out in favor of the new, explicit syntax.
+    In order to be backward-compatible, both old and new syntax are
+    currently supported.
+    Again, see the CM manual for details.
+. Parallel make is trying to be slightly smarter:  When the master
+    process finds a "bottleneck", i.e., when there is only one
+    compilation unit that can be compiled and everybody else is
+    waiting on it, then it will simply compile it directly instead
+    of clumsily telling one of the slaves to do it.
+. Support for "unsharing" added.  This is necessary in order to be
+    able to have two different versions of the same library running
+    at the same time (e.g., for trying out a new MLRISC while still
+    having the old MLRISC linked into the current compiler, etc.)
+    See the CM manual.
+. Simple "makedepend" functionality added for generating Makefile
+    dependency information.  (This is rather crude at the moment.
+    Expect some changes here in the future.)
+. ".fun" added as a recognized suffix for ML files. Also documented
+    explicitly in the manual that the fallback behavior (unknown suffix
+    -> ML file) is not an official feature!
+. Small changes to the pickler for stable libraries.
+. Several internal changes to CM (for cleanup/improvement).
+ !!!! NEW BINFILES !!!!
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/04/28 17:30:00 JST
+ Tag: blume-20000428-pathconfig
+ Description:
+. I changed config/install.sh to remove duplicate entries from the
+    lib/pathconfig file at the end.  Moreover, the final version of
+    lib/pathconfig is sorted alphabetically.  The same (sorting) is done
+    in src/system/installml.
+. The config/install.sh script now consistently uses relative
+    pathnames in lib/pathconfig whenever the anchor is in the lib
+    directory.  (So far this was true for the libraries that come
+    pre-compiled and bundled as part of the bootfiles but not for
+    libraries that are compiled by the script itself.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/04/26 13:10:00 JST
+ Tag: blume-20000426-fun_suffix
+ Description:
+ Added ".fun" as a recognized file name suffix (for ML code).
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/25 17:00:00 EST
+ Tag: leunga-20000425-alpha-ra
+ Description:
+. Alpha
+     PSEUDOARITH was missing in AlphaRewrite.  This causes an endless loop
+ in C--.
+. RA
+    Added a flag "ra-dump-size" to print out the size of the flowgraph
+    and the interference graph.
+ ----------------------------------------------------------------------
+ Name: Dave MacQueen
+ Date: 2000/04/25/
+ Tag: dbm-20000425-mlyacc_doc_examples
+ Description:
+   Updated mlyacc.tex sections 5 and 7 for SML '97 and CM.
+   Updated all three examples in src/ml-yacc/examples to run
+   under 110.* using CM.make.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/20 23:04:00 EST
+ Tag: leunga-20000420-ssa-c---stuff
+ Description:
+   This update synchronizes my repository with Yale's.  Most of these
+ changes, however, do not affect SML/NJ at all (the RA is an exception).
+. Register Allocator
+    a. An improvement in the interference graph construction:
+       Given a copy
+             s <- t
+       no interference edge between s and t is added for this definition of s.
+    b. I've added two new spill heuristic modules that Fermin and I developed
+       (in the new library RA.cm). These are unused in SML/NJ but maybe
+       useful for others (Moby?)
+. X86
+    a. Various fixes in the backend provided by Fermin [C--] and Lal.
+. Alpha
+    a. Added the BSR instruction and code generation that goes with it [C--]
+    b. Other fixes too numerous to recount provided by Fermin [C--]
+. Regmaps
+    a. The regmaps are not initialized with the identity physical bindings
+       at creation time.  This is unneeded.
+. MLRISC Optimizations
+    a. The DJ-Graph module can now compute the iterated dominance frontiers
+       intersects with liveness incrementally in linear time! Woohoo!
+       This is now used in my new SSA construction algorithm.
+    b. THe branch reorganization module is now smarter about linear chains of
+       basic blocks.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/04/12 13:52:00 JST
+ Tag: blume_main_v110p27_1
+ Description:
+ Changed install.sh script to handle archive files without version number
+ and to use "boot.<arch>-<os>" instead of "sml.boot.<arch>-<os>" for the
+ name of the boot file archive.
+ ----------------------------------------------------------------------
+ Name: Dave MacQueen
+ Date: 2000/04/09 14:00 EDT
+ Tag: dbm-20000410-Version_110_27
+ Description:
+. Updated src/compiler/TopLevel/main/version.sml to version 110.27
+. Updated src/config/version to 110.27
+. New boot files!
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/09 19:09:00 EST
+ Tag: leunga-20000409-misc
+ Description:
+.  Yet another fix for x86 assembly for idivl, imull, mull and friends.
+.  Miscellaneous improvements to MLRISC (unused in sml/nj)
+ ----------------------------------------------------------------------
+ Name: Stefan
+ Date: 2000/04/07 10:00:00 EDT
+ Tag: monnier-20000406-branch-handling
+ Description:
+ Improved handling of branches (mostly those generated from
+ polymorphic equality), removed switchoff and changed the
+ default optimization settings (more cpsopt and less flintopt).
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/06 01:30:00 EST
+ Tag: leunga-20000406-peephole-x86-SSA-2
+ Description:
+    Forgot a few files.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/06 00:36:00 EST
+ Tag: leunga-20000406-peephole-x86-SSA
+ Description:
+.  New Peephole code
+.  Minor improvement to X86 instruction selection
+.  Various fixes to SSA and machine description -> code translator
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/04/05 12:30:00 JST
+ Tag: blume_main_v110p26p2_3
+ Description:
+ This update just merges three minor cosmetic updates to CM's sources
+ to get ready for the 110.27 code freeze on Friday.  No functionality
+ has changed.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/04 19:39:00 EST
+ Tag: leunga-20000404-x86-asm
+ Description:
+.  Fixed a problem in X86 assembly.
+     Things like
+        jmp %eax
+        jmp (%eax)
+     should be output as
+        jmp *%eax
+        jmp *(%eax)
+.  Assembly output
+       Added a new flag
+           "asm-indent-copies" (default to false)
+       When this flag is on, parallel copies will be indented an extra level.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/04 03:18:00 EST
+ Tag: leunga-20000404-C--Moby
+ Description:
+     All of these fixes are related to C--, Moby, and my own optimization
+     stuff; so they shouldn't affect SML/NJ.
+.  X86
+     Various fixes related floating point, and extensions.
+.  Alpha
+     Some extra patterns related to loads with signed/zero extension
+     provided by Fermin.
+.  Assembly
+     When generating assembly, resolve the value of client defined constants,
+     instead of generating symbolic values.  This is controlled by the
+     new flag "asm-resolve-constants", which is default to true.
+.  Machine Descriptions
+     a. The precedence parser was slightly broken when parsing infixr symbols.
+     b. The type generalizing code had the bound variables reversed, resulting
+        in a problem during arity raising.
+     c. Various fixes in machine descriptions.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/04/03 16:05:00 JST
+ Tag: blume_main_v110p26p2_2
+ Description:
+ I eliminated coreEnv from compInfo.  Access to the "Core" structure is
+ now done via the ordinary static environment that is context to each
+ compilation unit.
+ To this end, I arranged that instead of "structure Core" as "structure
+ _Core" is bound in the pervasive environment.  Core access is done via
+ _Core (which can never be accidentally rebound because _Core is not a
+ legal surface-syntax symbol).
+ The current solution is much cleaner because the core environment is
+ now simply part of the pervasive environment which is part of every
+ compilation unit's context anyway.  In particular, this eliminates all
+ special-case handling that was necessary until now in order to deal
+ with dynamic and symbolic parts of the core environment.
+ Remaining hackery (to bind the "magic" symbol _Core) is localized in the
+ compilation manager's bootstrap compiler (actually: in the "init group"
+ handling).  See the comments in src/system/smlnj/init/init.cmi for
+ more details.
+ I also tried to track down all mentions of "Core" (as string argument
+ to Symbol.strSymbol) in the compiler and replaced them with a
+ reference to the new CoreSym.coreSym.  Seems cleaner since the actual
+ name appears in one place only.
+ Binfile and bootfile format have not changed, but the switchover from
+ the old "init.cmi" to the new one is a bit tricky, so I supplied new
+ bootfiles anyway.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/04/02 21:17:00 EST
+ Tag: leunga-20000402-mltree
+ Description:
+. Renamed the constructor CALL in MLTREE by popular demand.
+. Added a bunch of files from my repository.  These are currently
+       used by other non-SMLNJ backends.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/03/31 21:15:00 EST
+ Tag: leunga-20000331-aliasing
+ Description:
+ This update contains a rewritten (and hopefully more correct) module
+ for extracting aliasing information from CPS.
+    To turn on this feature:
+         Compiler.Control.CG.memDisambiguate := true
+    To pretty print the region information with assembly
+        Compiler.Control.MLRISC.getFlag "asm-show-region" := true;
+    To control how many levels of aliasing information are printed, use:
+        Compiler.Control.MLRISC.getInt "points-to-show-level" := n
+    The default of n is 3.
+ ----------------------------------------------------------------------
+ Name: David MacQueen
+ Date: 2000/03/31 11:15:00 EST
+ Tag: dbm-20000331-runtime_fix
+ Description:
+ This update contains:
+. runtime/c-lib/c-libraries.c
+    includes added in revision 1.2 caused compilation errors on hppa-hpux
+. fix for bug 1556
+    system/Basis/Implementation/NJ/internal-signals.sml
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/03/31 18:00:00 JST
+ Tag: blume_main_v110p26p2_1
+ Description:
+ This update contains:
+. A small change to CM's handling of stable libraries:
+    CM now maintains one "global" modmap that is used for all stable
+    libraries.  The use of such a global modmap maximizes sharing and
+    minimizes the need for re-traversing parts of environments during
+    modmap construction.  (However, this has minor impact since modmap
+    construction seems to account for just one percent or less of total
+    compile time.)
+. I added a "genmap" phase to the statistics.  This is where I got the
+    "one percent" number (see above).
+. CM's new tool parameter mechanism just became _even_ better. :)
+    - The parser understands named parameters and recursive options.
+    - The "make" and "shell" tools use these new features.
+      (This makes it a lot easier to cascade these tools.)
+    - There is a small syntax change: named parameters use a
+        <name> : ( <option> ... )            or
+        <name> : <string>
+      syntax.  Previously, named parameters were implemented in an
+      ad-hoc fashion by each tool individually (by parsing strings)
+      and had the form
+        <name>=<string>
+    See the CM manual for a full description of these issues.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2000/03/30 18:00:00 JST
+ Tag: blume_main_v110p26p2_0
+ Description:
+ !!!!! WARNING !!!!!!
+ !!  New binfiles  !!
+ !!!!!!!!!!!!!!!!!!!!
+ This update contains:
+. Moderate changes to CM:
+    - Changes to CM's tools mechanism.  In particular, it is now possible
+    to have tools that accept additional "command line" parameters
+    (specified in the .cm file at each instance where the tool's class is
+    used).
+    This was done to accommodate the new "make" and "shell" tools which
+    facilitate fairly seamless hookup to portions of code managed using
+    Makefiles or Shell scripts.
+    There are no classes "shared" or "private" anymore.  Instead, the
+    sharing annotation is now a parameter to the "sml" class.
+    There is a bit of generic machinery for implementing one's own
+    tools that accept command-line parameters.  However, I am not yet fully
+    satisfied with that part, so expect changes here in the future.
+    All existing tools are described in the CM manual.
+    - Slightly better error handling.  (CM now suppresses many followup
+    error messages that tended to be more annoying than helpful.)
+. Major changes to the compiler's static environment data structures.
+    - no CMStaticEnv anymore.
+         - no CMEnv, no "BareEnvironment" (actually, _only_ BareEnvironment,
+           but it is called Environment), no conversions between different
+           kinds of static environments
+    - There is still a notion of a "modmap", but such modmaps are generated
+      on demand at the time when they are needed.  This sounds slow, but I
+      sped up the code that generates modmaps enough for this not to lead to
+      a slowdown of the compiler (at least I didn't detect any).
+    - To facilitate rapid modmap generation, static environments now
+      contain an (optional) "modtree" structure.  Modtree annotations are
+      constructed by the unpickler during unpickling.  (This means that
+      the elaborator does not have to worry about modtrees at all.)
+      Modtrees have the advantage that they are compositional in the same
+      way as the environment data structure itself is compositional.
+      As a result, modtrees never hang on to parts of an environment that
+      has already been rendered "stale" by filtering or rebinding.
+    - I went through many, many trials and errors before arriving at the
+      current solution.  (The initial idea of "linkpaths" did not work.)
+      But the result of all this is that I have touched a lot of files that
+      depend on the "modules" and "types" data structures (most of the
+      elaborator). There were a lot of changes during my "linkpath" trials
+      that could have been reverted to their original state but weren't.
+      Please, don't be too harsh on me for messing with this code a bit more
+      than what was strictly necessary...  (I _did_ resist the temptation
+      of doing any "global reformatting" to avoid an untimely death at
+      Dave's hands. :)
+    - One positive aspect of the previous point:  At least I made sure that
+      all files that I touched now compile without warnings (other than
+      "polyEqual").
+    - compiler now tends to run "leaner" (i.e., ties up less memory in
+      redundant modmaps)
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2000/03/29 18:00:00
+ Tag: leunga-20000327-mlriscGen_hppa_alpha_x86
+ Boot files (optional): ftp://react-ilp.cs.nyu.edu/leunga/110.26.1-sml.boot.x86-unix-20000330.tar.gz
+ Description:
+    This update contains *MAJOR* changes to the way code is generated from CPS
+ in the module mlriscGen, and in various backend modules.
+ CHANGES
+ =======
+. MLRiscGen: forward propagation fix.
+    There was a bug in forward propagation introduced at about the same time
+    as the MLRISC x86 backend, which prohibits coalescing to be
+    performed effectively in loops.
+    Effect: speed up of loops in RISC architectures.
+            By itself, this actually slowed down certain benchmarks on the x86.
+. MLRiscGen:  forward propagating addresses from consing.
+    I've changed the way consing code is generated.  Basically I separated
+    out the initialization part:
+         store tag,   offset(allocptr)
+         store elem1, offset+4(allocptr)
+         store elem2, offset+8(allocptr)
+         ...
+         store elemn, offset+4n(allocptr)
+    and the address computation part:
+         celladdr <- offset+4+alloctpr
+    and move the address computation part
+    Effect:  register pressure is generally lower as a result.  This
+             makes compilation of certain expressions much faster, such as
+             long lists with non-trivial elements.
+              [(0,0), (0,0), .... (0,0)]
+. MLRiscGen: base pointer elimination.
+     As part of the linkage mechanism, we generate the sequence:
+      L:  ...  <- start of the code fragment
+      L1:
+          base pointer <- linkreg - L1 + L
+      The base pointer was then used for computing relocatable addresses
+    in the code fragment.  Frequently (such as in lots of continuations)
+    this is not needed.  We now eliminate this sequence whenever possible.
+      For compile time efficiency, I'm using a very stupid local heuristic.
+    But in general, this should be done as a control flow analysis.
+    Effect:  Smaller code size.  Speed up of most programs.
+. Hppa back end
+      Long jumps in span dependence resolution used to depend on the existence
+   of the base pointer.
+      A jump to a long label L was expanded into the following sequence:
+       LDIL %hi(L-8192), %r29
+       LDO  %lo(L-8192)(%r29), %r29
+       ADD  %r29, baseptr, %r29