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[smlnj] Diff of /sml/trunk/HISTORY

[smlnj] / sml / trunk / HISTORY

Diff of /sml/trunk/HISTORY

-revision 749, Fri Dec  8 15:16:36 2000 UTC
+revision 1482, Fri Apr 23 22:39:17 2004 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 (blume (at) tti - c (dot) org)
+ Date: 2004/04/23 17:40:00 CDT
+ Tag: blume-20040423-ieee-scan
+ Description:
+ Fixed IEEEReal.scan (and .fromString) so that if there is an overflow
+ in the exponent calculation we get INF or ZERO (depending on the mantissa
+ and the sign of the exponent).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2004/04/23 10:40:00 CDT
+ Tag: blume-20040423-ml-build
+ Description:
+ The ml-build script now terminates with a non-0 status when something
+ goes wrong.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2004/04/22 16:35:00 CDT
+ Tag: blume-20040422-Option
+ Description:
+ Made exception Option to be the same as exception Option.Option
+ (as it should be).
+ ----------------------------------------------------------------------
+ Name: Allen Leung (leunga (at) reservoir (dot) com)
+ Date: 2004/03/19 14:40:00 EST
+ Tag: leunga-20040319-cygwin-nlffi
+ Description:
+ Fixed the runtime so that ml-nlffi-lib runs on the cygwin version
+ of SML/NJ.  The problem is that
+    lib = dlopen(NULL, ...)
+    f   = dlsym(lib, "malloc");
+ does not work on Windows unless we explicitly export symbols
+ such as 'malloc' during linking.  We fixed this by explicitly
+ exporting the required symbols with the magic gcc incantation:
+     -Wl,--export-all cygwin.def
+ where cygwin.def is a file containing all the symbols that
+ we wish to export.
+ I suspect this is a Windows problem and we'll have to
+ do the same (somehow with windows compilers) when
+ we build the native win32 version with the system
+ calls LoadLibrary/GetProcAddress.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2004/03/04 16:35:00 CST
+ Tag: blume-20040304-intinf-fmt
+ Description:
+ Fixed problem with IntInf.fmt (sign would show up on the right instead
+ of on the left for BIN, OCT, and HEX).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2004/03/04 11:25:00 CST
+ Tag: blume-20040304-symlinks
+ Description:
+ Fixed problem with installer script (unix only) where bin/ml-yacc and
+ friends pointed (via symlinks) to absolute locations instead of just
+ .run-sml.  This was reported by Vesa A Norrman.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2004/02/13 14:50:00 CST
+ Tag: Release_110_45
+ Description:
+ New working version (110.45). New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2004/01/26 15:15:15 CST
+ Tag: blume-20040126-toplevel
+ Description:
+ Improved handling of exceptions at the interactive toplevel.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2004/01/26 11:25:00
+ Tag: blume-20040126-app
+ Description:
+ Type of top-level "app" corrected.
+ Added code for setting vp_limitPtrMask to Win32-specific runtime.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/11/18 17:10 CST
+ Tag: blume-20031118-basis-fiddle
+ Description:
+ - changed Timer interface to what might become the spec
+ - POSIX_FLAGS -> BIT_FLAGS according to spec
+ - some other minor discrepancies wrt. spec eliminated
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/11/06 12:00:00 CST
+ Tag: Release_110_44
+ Description:
+ New working version (110.44). New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/11/04 11:50:00 CST
+ Tag: blume-20031104-move-libraries
+ Description:
+ Eliminated the "dont_move_libraries" directive in config/targets.
+ (The mechanism was broken and could not be fixed easily.  Moreover,
+ there does not seem to be any reason not to move all libraries into
+ lib during installation.  I originally implemented this directive as a
+ backward-compatibility feature when I first introduced the new CM.
+ Now that things have been stable for a long time and going back to the
+ old CM is not an option, there is no reason to keep it around.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/11/03 16:00:00 CST
+ Tag: blume-20031103-installdir
+ Description:
+ Made installer honor INSTALLDIR variable again.  (Thanks to Chris
+ Richards for pointing out the problem and providing the solution.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/10/01 17:05:00 CDT
+ Tag: blume-20031001-lal-mlrisc
+ Description:
+ MLRISC bug fix from Lal.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/30 16:10:00 CDT
+ Tag: blume-20030930-primio-bat
+ Description:
+. Added openVector, nullRd, and nullWr to PRIM_IO.
+. Improved .bat files (for Win32 port) to make things work under Win95.
+    (thanks to Aaron S. Hawley for this one)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/26 16:05:00 CDT
+ Tag: blume-20030926-wrappriv
+ Description:
+ Added missing wrapper for privilege "primitive" in $smlnj/viscomp/core.cm.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/26 15:00:00 CDT
+ Tag: blume-20030926-110_43_3
+ Description:
+ - additional cleanup
+ - version number bump, NEW BOOTFILES
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/26 12:00:00 CDT
+ Tag: blume-20030926-ppautoload
+ Description:
+ I modified the read-eval-print loop so that the autoloader gets
+ invoked whenever the prettyprinter tries to look up a symbol that
+ is not currently defined in the toplevel environment but which
+ appears in CM's autoload registry.  As a result, we see far fewer of
+ those ?.Foo.Bar.xxx names in the prettyprinter's output.
+ In addition to this I tried to clean up some pieces of the Basis
+ implementation (e.g., Socket, Word8Array) in order to prevent other
+ instances of these ?.Foo.Bar.xxx names from being printed.
+ The mechanism that picks names for types still needs some work, though.
+ (Right now it seems that if there is a type A.t which is defined to
+ be B.u, but B is unavailable at toplevel, then A.t gets printed as
+ "?.B.u" although the perhaps more sensible solution would be to use
+ "A.t" in this case.  In other words, the prettyprinter should follow
+ a chain of DEFtycs not farther than there are corresponding toplevel
+ names in the current environment.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/24 16:31:00 CDT
+ Tag: blume-20030924-installer
+ Description:
+ Another installer tweak:  All the ML code for the installer is now
+ compiled during CMB.make and put into a little library called
+ $smlnj/installer.cm.  The installation then simply invokes
+    sml -m $smlnj/installer.cm
+ and everything happens automagically.
+ Win32:  ML code senses value of environment variable SMLNJ_HOME.
+ Unix:   ML code senses values of environment variables ROOT, CONFIGDIR,
+         and BINDIR.
+ The new scheme guarantees that the ML code responsible for the installation
+ is in sync with the APIs of the main system.  Also, the installer is
+ somewhat faster because the installer script is precompiled.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/24 15:35:00 CDT
+ Tag: blume-20030924-synsock
+ Description:
+ Added a signature SYNCHRONOUS_SOCKET to basis.cm.  This is like SOCKET
+ but excludes all non-blocking operations.  Defined SOCKET (in Basis)
+ and CML_SOCKET in terms of SYNCHRONOUS_SOCKET.  Removed superfluous
+ implementations of non-blocking operations from CML's Socket
+ structure.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/24 15:10:05 CDT
+ Tag: blume-20030924-sockets
+ Description:
+. Fixed SOCKET API and implementation to match Basis spec.
+    This required changing the internal representation of sockets to one
+    that remembers (for each socket file descriptor) whether it is currently
+    blocking or non-blocking.  This state is maintained lazily (i.e., a system
+    call is made only if the state actually needs to change).
+. OS-specific details of sockets were moved into separate files, thus
+    making it possible to unify the bulk of the socket implementations
+    between Unix and Win32.
+. CML's socket API changed accordingly.
+    (Note that we need to remove non-blocking functions from this API
+    since they are redundant in the case of CML!)
+. CML's socket implementation now makes use of non-blocking functions
+    provided by Basis, thus removing all OS-dependent code from this part
+    of CML.
+. Changed Real64.precision from 52 to 53.  Minor cleanup in Real64 code.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/22 12:10:00 CDT
+ Tag: blume-20030922-110_43_2
+ Description:
+ Made a new interim version and bootfiles for developer's bootstrapping
+ convenience.
+.43.2 -- NEW BOOTFILES
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/19 15:55:00 CDT
+ Tag: blume-20030919-cmdir
+ Description:
+. new-install.sh -> install.sh
+. changed default CM "metadata" directory name to ".cm" (instead of "CM")
+. tweaked installer so that another name instead of .cm can be chosen
+    at install time (by setting the CM_DIR_ARC environment variable
+    during installation); once installation is complete, the name is
+    fixed
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/18 16:00:00 CDT
+ Tag: blume-20030918-110_43_1
+ Description:
+ Made a new interim version and bootfiles for developer's bootstrapping
+ convenience.
+.43.1 -- NEW BOOTFILES
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/18 15:20:00 CDT
+ Tag: blume-20030918-misc
+ Description:
+. Exported fractionsPerSecond etc. from TimeImp (but not from Time as
+    this seems to be controversial at the moment) and used those in
+    Posix.ProcEnv.times.
+. Added Time.{from,to}Nanoseconds to Time.
+. Improved Real.{from,to}LargeInt by avoiding needless calculations.
+    For example, fromLargeInt never needs to look at more than 3 "big
+    digits" to get its 53 bits of precision.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/17 16:30:00 CDT
+ Tag: blume-20030917-real32-slices
+ Description:
+ Added an entry to the primitive environment
+ (compiler/Semant/statenv/prim.sml) for int32->real64 conversion and
+ added code to compiler/CodeGen/main/mlriscGen.sml to implement it.
+ Removed some of the "magic" constants in real64.sml and replaced them
+ with code that generates these values from their corresponding
+ integer counterparts.
+ Made all(?) the slice-related changes to the Basis and made everything
+ compile again...
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/15 17:45:00 CDT
+ Tag: blume-20030915-rbase
+ Description:
+ Fixed bug in Real.fromLargeInt.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/13 18:11:00 CDT
+ Tag: blume-20030913-libinstall
+ Description:
+ Minor bugfix in config/libinstall (set anchor with path to
+ standalone tool after installing it, otherwise libraries that
+ need ml-lex or ml-yacc won't compile the first time the installer
+ runs).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/12 11:45:00 CDT
+ Tag: blume-20030912-various
+ Description:
+  - fixed bug in Real.toLargeInt
+  - fixed bug in Posix.ProcEnv.times
+  - changed inputLine functions to return an option
+  - minor installer improvements / bugfixes
+  - changed default @SMLalloc parameter for x86/celeron to 64k
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/09 22:00:00 CDT
+ Tag: Release_110_43
+ Description:
+     New working release 110.43.  New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/09 19:20:00 CDT
+ Tag: blume-20030909-installer
+ Description:
+ Rewrote large parts of config/install.sh in SML (config/libinstall.sml).
+ Modified config/install.bat to take advantage of it.  Also modified
+ config/install.sh (and called it config/new-install.sh) to take advantage
+ of it on Unix systems.  (The SML code is (supposed to be) platform-
+ independent.)
+ The installer can now install everything under Win32
+ as well as under *nix as long as it compiles.
+ Other changes:
+   - made CML compile again under Win32
+   - made eXene compile under Win32 (by providing a fake structure UnixSock
+     and by using OS.Process.getEnv instead of Posix.ProcEnv.getenv)
+   - fixed a bug in nowhere: it assumed that type OS.Process.status is the
+     same as type int;  under Win32 it isn't
+   - fixed some slice-related problems in the win32-specific parts of CML
+   - added a functor argument "sameVol" to os-path-fn.sml in the Basis
+     (under Win32, the volume name is case-insensitive, and the
+     OS.Path code compares volume names for equality)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/08 11:55:00 CDT
+ Tag: blume-20030908-fullpath
+ Description:
+ Made Win32 version of OS.FileSys.fullPath return current directory
+ when given an empty string.  This is what the spec says, and incidentally,
+ CM depends on it.  (CM otherwise goes into an infinite loop in certain
+ cases when presented with the name of a non-existing .cm file.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/09/04 16:30:00 CDT
+ Tag: blume-20030905-slices-etc
+ Description:
+. Changed interface to vectors and arrays in Basis to match
+      (draft) Basis spec.
+. Added signatures and implementations of slices according to
+      Basis spec.
+. Edited source code throughout the system to make it compile again
+      under 1. and 2.  (In some cases code had to be added to have it
+      match the new signatures.)
+. MLRISC should be backward-compatible: the copies of the originals
+      of files that needed to change under 3. were retained, the .cm files
+      check the compiler version number and use old versions when
+      appropriate.
+. Changed type of OS.FileSys.readDir and Posix.FileSys.readdir to
+      dirstream -> string option (in accordance with Basis spec).
+. When generating code that counts lines, ml-lex used function
+      CharVector.foldli, taking advantage of its old interface.
+      This has been replaced with the corresponding code from
+      CharVectorSlice.  (html-lex must be re-lexed!)
+. BitArray in smlnj-lib/Util has been extended/modified to match the
+      new MONO_ARRAY signature.  (Do we need BitArraySlice?)
+. Removed temporary additions (fromInternal, toInternal) from the
+      (now obsolete) IntInf in smlnj-lib/Util.
+. Cleaned up structure Byte.
+. Added localOffset, scan, and fromString to Date (according to spec).
+      Cleaned/corrected implementation of Date.
+      (Still need to check for correctness; implement better canonicalizeDate.)
+. Added "scan" to signature IEEE_REAL.
+. Some improvements to IntInf [in particular: efficiency-hack for
+      mod and rem when second operand is 2 (for parity checks).]
+. Changed representation of type Time.time, using a single IntInf.int
+      value counting microseconds.  This considerably simplified the
+      implementation of structure Time.  We now support negative time
+      values; scan and fromString handle signs.
+. Functor PrimIO now takes two additional arguments (VectorSlice and
+      ArraySlice).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/08/28 17:00:00 CDT
+ Tag: blume-20030828-intinf
+ Description:
+ This is a major update which comes with a version number bump
+ (110.42.99 -- yes, we are really close to 110.43 :-), NEW BOOTFILES,
+ and an implementation of IntInf in the Basis.
+ There are a fairly large number of related changes and updates throughout
+ the system:
+ Basis:
+         - Implemented IntInf.
+         - Made LargeInt a projection of IntInf (by filtering through INTEGER).
+         - Added some missing Real64 operations, most notably Real.toLargeInt.
+         - Added FixedInt as a synonym for Int32.
+ compiler:
+         * Added support for a built-in intinf type.
+           - literals
+           - pattern matching
+           - conversion shortcuts (Int32.fromLarge o Int.toLarge etc.)
+           - overloading on literals and operations
+         This required adding a primitive type intinf, some additional
+         primops, and implementations for several non-trivial intinf
+         operations in Core.  (The intinf type is completely abstract
+         to the compiler; all operations get delegated back to the Core.)
+         * Intinf equality is handled by polyequal.  However, the compiler
+         does not print its usual warning in this case (since polyequal
+         is the right thing to do there).
+         * Improved the organization of structure InlineT.
+         * A word about conversion primops:
+         If conversions involving intinf do not cancel out during
+         CPS contract, then the compiler must insert calls to Core functions.
+         Since all core access must be resolved already during the FLINT
+         translate phase, it would be too late a the time of CPS contract
+         to add new Core calls.  For this reason, conversion primops
+         for intinf carry two arguments:  1. the numeric argument that
+         they are supposed to convert, and 2. the Core function that
+         can help with this conversion if necessary.  If CPS contract
+         eliminates a primop, then the associated Core function becomes
+         dead and goes away.  Intinf conversion primops that do not get
+         eliminated by CPS contract get rewritten into calls of their
+         core functions by a separate, new phase.
+ interactive system:
+         - Control.Print.intinfDepth controls max length of intinf constants
+         being printed. (Analogous to Control.Print.stringDepth.)
+         - Cleanup in printutil and pputil: got rid of unused stuff and
+         duplicates; replaced some of the code with code that makes better
+         use of library functionality.
+ CM:
+         Bugfix: parse-errors in init group (system/smlnj/init/init.cmi)
+         are no longer silent.
+ CKIT:
+         Fixed mismatched uses of Int32 and LargeInt.  I always decided
+         in favor of LargeInt -- which is now the same as IntInf.
+         CKIT-knowledgable people should check whether this is what's
+         intended and otherwise change things back to using Int32 or
+         FixedInt.
+ Throughout the code:
+         Started using IntInf.int literals and built-in operations
+         (e.g., comparison with 0) where this seems appropriate.
+ ----------------------------------------------------------------------
+ Name: Dave MacQueen (dbm@cs.uchicago.edu)
+ Date: 2003/08/13 11:36:00 CDT
+ Tag: dbm-20030813-mcz-merge1
+ Description:
+ Merging changes from the mcz-branch development branch into trunk.
+ These changes involve replacement of the emulated old prettyprinter
+ interface with direct use of the SML/NJ Lib PP library, and fixing
+ of a couple of bugs (895, 1186) relating to error messages.  A new
+ prettyprinter for ast datatypes (Elaborator/print/ppast.{sig,sml})
+ has been added.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/08/11 15:45:00 CDT
+ Tag: blume-20030811-windows
+ Description:
+ Version number bumped to 110.42.9.  NEW BOOTFILES!!!
+     http://smlnj.cs.uchicago.edu/dist/working/110.42.9/
+ This patch restores SML/NJ's ability to run under win32.  There are a
+ number of changes, including fixes for several bugs that had gone
+ unnoticed until now:
+   - uname "CYGWIN_NT*" is recognized as win32 (This is relevant only when
+     trying to run the win32 version from within cygwin.)
+   - There are a number of simple .bat scripts that substitute for their
+     corresponding Unix shell-scripts.  (See below.)
+   - The internals of ml-build have been modified slightly.  The main
+     difference is that instead of calling ".link-sml" (or link-sml.bat)
+     using OS.Process.system, the ML process delegates this task back
+     to the script.  Otherwise problems arise in mixed environments such
+     as Cygwin where scripts look and work like Unix scripts, but
+     where OS.Process.system cannot run them.
+   - In CM, the srcpath pickler used native pathname syntax -- which
+     is incorrect in the case of cross-compilation.  The new pickle format
+     is independent of platform-specific naming conventions.
+   - Path configuration files (such as lib/pathconfig) can now choose
+     between native and standard syntax.  Placing a line of the form
+         standard!
+     into the file causes all subsequent paths to be interpreted using
+     CM standard pathname syntax (= Unix conventions); a line
+         native!
+     switches back to native style.  This was needed so that
+     path config files can be written portably, see src/system/pathconfig.
+   - Runtime system:
+       - win32-filesys.c:  get_file_time and set_file_time now
+         access modification time, not creation time.
+       - I/O code made aware of new array representation.
+       - Bug fixes in X86.prim.masm.
+    - src/system/makeml made aware of win32. (For use under cygwin
+         and other Unix-environments for windows.)
+    - In Basis, fixed off-by-one error in win32-io.sml (function vecF)
+      which caused BinIO.inputAll to fail consistently.
+ .bat scripts:
+    Windows .bat scripts assume that SMLNJ_HOME is defined.
+    - sml.bat, ml-yacc.bat, ml-lex.bat:  Driver scripts for standalone
+      applications (sml, ml-yacc, ml-lex).
+    - ml-build.bat: analogous to ml-build.
+    - config\install.bat:  Analogous to config/install.sh.  This requires
+      that SMLNJ_HOME is set and that Microsoft Visual C is ready to use.
+      (nmake etc. must be on the path, and vcvars32 must have been run.)
+      Moreover, sources for ml-lex and ml-yacc need to exist under src,
+      and the bootfile hierarchy must have been unpacked under
+      sml.boot.x86-win32.
+      The script is very primitive and does a poor job at error checking.
+      It only installs the base system, ml-lex, and ml-yacc.  No other
+      libraries are being installed (i.e., you get only those that
+      are part of the compiler.)
+    - link-sml.bat:  analogous to .link-sml, but not currently used
+ Unrelated bug fixes:
+   - ml-nlffigen now exports structures ST_* corresponding to incomplete
+     types.
+   - Added getDevice to PP/src/pp-debug-fn.sml.  (Would not compile
+     otherwise.)
+ ----------------------------------------------------------------------
+ Name: Dave MacQueen (macqueen@cs.uchicago.edu)
+ Date: 2003/06/17
+ Tag: macqueen-20030617-bug895
+ Description:
+ Modified compiler/Elaborator/print/pptype.sml to fix bug 895.
+ Tag will be used for new development branch (mcz-branch) for
+ use by MacQueen, (Lucasz) Zairek, and (George) Cao at uchicago.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/05/27 16:55:00 CDT
+ Tag: blume-20030527-polyeq
+ Description:
+ Tried to eliminated most cases of polymorphic equality.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/05/21 17:45:00 CDT
+ Tag: blume-20030517-complete
+ Description:
+ Two changes:
+. Added a flag for controlling whether non-exhaustive bindings will
+      be treated as errors (default is false).
+. Cleaned up the *entire* source tree so that CMB.make goes through
+      without a single non-exhaustive match- or bind warning.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume (blume (at) tti - c (dot) org)
+ Date: 2003/05/17 10:20:00 CDT
+ Tag: blume-20030517-absyn
+ Description:
+. Added cases for IF, WHILE, ANDALSO, and ORELSE to Absyn.
+    This mainly affects the quality of error messages.  However, some
+    of the code is now more straightforward than before. (Treatment of
+    the above four constructs in translate.sml is much simpler than
+    the "macro-expansion" that was going on before.  Plus, the mach-
+    compiler no longer gets invoked just to be able to compile an
+    if-expression.)
+. The ErrorMsg.Error exception is now caught and absorbed by the
+    interactive loop.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2003/05/16 13:05:00 CDT
+ Tag: leunga-20030516-cygwin-runtime
+ Description:
+     Ported the runtime system to cygwin, which uses the unix
+ x86-unix bin files.  Missing/buggy features:
+    o getnetbyname, getnetbyaddr: these functions seem to be missing in
+      the Cygwin library.
+    o Ctrl-C handling may be flaky.
+    o Windows system calls and Windows I/O are not supported.
+    A new set of binfiles is located at:
+      http://www.dorsai.org/~leunga/boot.x86-unix.tgz
+    This is only needed for bootstrapping the cygwin version of smlnj.
+    Other x86 versions can use the existing binfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2003/04/08 15:42:00 CDT
+ Tag: blume-20030408-listpair
+ Description:
+. Added a target 'mlrisc' to installer.
+. Added missing elements to structure ListPair.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2003/01/07 10:40:00 EST
+ Tag: leunga-20030107-int-rem
+ Description:
+ Fixed a bug in Int.rem(x,y) where y is a power of 2 on x86.
+ The arguments to the SUBL instruction were swapped.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/12/12 16:25:00 EST
+ Tag: blume-20021212-risc-ra
+ Description:
+ Fixed a serious bug in the rewrite code for FP spilling/reloading that
+ sent the RA into an infinite loop when floating point registers get
+ spilled.  (Because of this bug, e.g., nucleic stopped compiling between
+.37 and 110.38.)
+ There was another set of potential problems related to the handling of
+ MLRISC annotations (but those did not yet cause real problems, apparently).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/12/06 22:40:00 EST
+ Tag: blume-20021206-cm-fileid
+ Description:
+ Added a call of SrcPath.sync at the beginning of Parse.parse (in CM).
+ This fixes the problem of CM getting confused by files that suddenly
+ change their identity (e.g., by getting unlinked and recreated by some
+ text editor such as vi).  There might be a better/cheaper/cleaner way
+ of doing this, but for now this will have to do.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/10/28 09:50:00 EST
+ Tag: blume-20021028-typecheck
+ Description:
+ Exported structure Typecheck from $smlnj/viscomp/core.cm.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/10/17 09:10:00 EDT
+ Tag: Release_110_42
+ Description:
+ In good old tradition, there has been a slight hiccup so that we have
+ to patch 110.42 after the fact.   The old release tag has been replaced
+ (see below).
+ The change solves a problem with two competing approaches the
+ configuration problem regarding MacOS 10.1 vs. MacOS 10.2 which got in
+ each other's way.
+ This change only affects the runtime system code and the installer script.
+ (No new bootfiles.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/10/16 12:00:00 EDT
+ Tag: Release_110_42_removed
+ Description:
+ New working release.  New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/10/10 13:10:00 EDT
+ Tag: blume-20021010-ppc-divs
+ Description:
+ The mltree operator DIVS must be implemented with an overflow check on
+ the PPC because the hardware indicates divide-by-zero using "overflow" as
+ well.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/07/23 11:45:00
+ Tag: blume-20020723-smlnj-home
+ Description:
+ Sml now senses the SMLNJ_HOME environment variable.  If this is set,
+ then the bin dir is assumed to be in $SMLNJ_HOME/bin and (unless
+ CM_PATHCONFIG is also set), the path configuration file is assumed
+ to be in $SMLNJ_HOME/lib/pathconfig.  This way one can easily move
+ the entire tree to some other place and everything will "just work".
+ (Companion commands such as ml-build and ml-makedepend also sense this
+ variable.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/07/12 21:19:00 EDT
+ Tag: blume-20020712-liveness
+ Description:
+ Exported two useful "step" functions from liveness module (MLRISC).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/07/05 16:00 EDT
+ Tag: Release_110_41
+ Description:
+ New working release.  New bootfiles.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/07/05 10:25:00 EDT
+ Tag: blume-20020705-btimp
+ Description:
+ Exported structure BTImp from $smlnj/viscomp/debugprof.cm so that
+ other clients can set up backtracing support.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/06/25 17:23:00 EDT
+ Tag: blume-20020625-fpmax
+ Description:
+ Fixed a bug in translation of INLMAX (and INLMIN) for the floating-point
+ case.  (The sense of the isNaN test was reversed -- which made min and
+ max always return their first argument.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/06/11
+ Tag: blume-20020611-unixpath
+ Description:
+ Back-ported OS.Path.{from,to}UnixPath from idlbasis-devel branch.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/06/10 16:35:00 EDT
+ Tag: blume-20020610-ieeereal
+ Description:
+ I back-ported my implementation of IEEEReal.fromString from the
+ idlbasis-devel branch so that we can test it.
+ Another small change is that ppDec tries to give more information
+ than just "<sig>" in the case of functors.  However, this code is
+ broken in some mysterious way if the functor's body's signature
+ has not been declared by ascription but gets inferred from the
+ implementation.  This needs fixing...
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/31
+ Tag: blume-20020531-btrace-mode
+ Description:
+ Resurrected SMLofNJ.Internals.BTrace.mode.  (It accidentally fell by
+ the wayside when I switched over to using Controls everywhere.)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/05/23 12:21:40 EDT
+ Tag: george-20020523-visual-labels
+ Description:
+ Labels are now displayed in the graphical output to make
+ the fall-through and target blocks obvious.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/22 11:03:00 EDT
+ Tag: blume-20020522-shrink
+ Description:
+ John tweaked yesterday's fix for 1131 to handle an out-of-memory
+ situation that comes up when allocating huge arrays.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/21 16:00:00 EDT
+ Tag: Release_110_40
+ Description:
+ New working release (110.40).  New bootfiles.
+ [Also: John Reppy fixed GC bug 1131.]
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/21 12:35:00 EDT
+ Tag: blume-20020521-cmdoc
+ Description:
+ CM documentation update.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/21 10:55:00 EDT
+ Tag: blume-20020521-misc
+ Description:
+ - John tweaked runtime to be silent on heap export (except when
+   GC messages are on).
+ - I added a few more things (cross-compiling versions of CMB) to
+   config/preloads (as suggestions).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/20 22:25:00 EDT
+ Tag: blume-20020520-controls
+ Description:
+ - Added ControlUtil structure to control-lib.cm.
+ - Use it throughout.
+ - Used Controls facility to define MLRISC controls (as opposed to
+   registering MLRISC control ref cells with Controls after the fact)
+ - Fixed messed-up controls priorities.
+ * Removed again all the stuff from config/preloads that one wouldn't
+   be able to preload at the time the initial heap image is built.
+   (Many libraries, e.g., CML, do not exist yet at this time.  The
+    only libraries that can be preloaded via config/preloads are those
+    that come bundled with the bootfiles.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/20 10:59:00 EDT
+ Tag: blume-20020520-preloads
+ Description:
+ Added a lot of commented-out suggestions for things to be included
+ in config/preloads.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/05/18 14:20:00 EDT
+ Tag: leunga-20020518-mdl
+ Description:
+ o Made the mdl tool stuff compile and run again.
+ o I've disabled all the stuff that depends on RTL specifications; they
+   are all badly broken anyway.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/17 16:49:00 EDT
+ Tag: blume-20020517-controls
+ Description:
+. John Reppy made several modifications to the SML/NJ library.
+    In particular, there is a shiny new controls-lib.cm.
+. Pushed new controls interface through compiler so that everything
+    compiles again.
+. Added FormatComb and FORMAT_COMB to the CML version of the
+    SML/NJ library (so that CML compiles again).
+. Modified init scripts because XXX_DEFAULT environment variables
+    are no longer with us.  (Boot-time initialization is now done
+    using the same environment variables that are also used for
+    startup-time initialization of controls.)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/05/15 09:20:10 EDT
+ Tag: george-20020515-pseudo-op-decls
+ Description:
+         All pseudo-ops emitted before the first segment declaration
+ such as TEXT, DATA, and BSS directives are assumed to be global
+ declarations and are emitted first in the assembly file. This is
+ useful in a number of situations where one has pseudo-ops that are not
+ specific to any segment, and also works around the constraint that one
+ cannot have client pseudo-ops in the TEXT segment.
+         Because no segment is associated with these declarations it is
+ an error to allocate any space or objects before the first segment
+ directive and an exception will be raised. However, we cannot make
+ this check for client pseudo-ops.
+         These top level declarations are a field in the CFG graph_info.
+ In theory you can continue to add to this field after the CFG has been
+ built -- provided you know what you are doing;-)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/13 16:40:00 EDT
+ Tag: blume-20020513-pp-etc
+ Description:
+ A few minor bugfixes:
+   - Stopgap measure for bug recently reported by Elsa Gunter (ppDec).
+     (Bogus printouts for redefined bindings still occur.  Compiler
+     bug should no longer occur now.  We need to redo the prettyprinter
+     from scratch.)
+   - CM pathname printer now also adds escape sequences for ( and )
+   - commend and docu fixes for ml-nlffi
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/05/10 16:40:00 EDT
+ Tag: blume-20020510-erg-textio
+ Description:
+ Applied the following bugfix provided by Emden Gansner:
+     Output is corrupted when outputSubstr is used rather than output.
+     The problem occurs when a substring
+         ss = (s, dataStart, dataLen)
+     where dataStart > 0, fills a stream buffer with avail bytes left.
+     avail bytes of s, starting at index dataStart, are copied into the
+     buffer, the buffer is flushed, and then the remaining dataLen-avail
+     bytes of ss are copied into the beginning of the buffer. Instead of
+     starting this copy at index dataStart+avail in s, the current code
+     starts the copy at index avail.
+     Fix:
+     In text-io-fn.sml, change line 695 from
+          val needsFlush = copyVec(v, avail, dataLen-avail, buf, 0)
+     to
+          val needsFlush = copyVec(v, dataStart+avail, dataLen-avail, buf, 0)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/04/12 13:55:00 EDT
+ Tag: blume-20020412-assyntax
+ Description:
+. Grabbed newer assyntax.h from the XFree86 project.
+. Fiddled with how to compile X86.prim.asm without warnings.
+. (Very) Minor cleanup in CM.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/04/01 (no joke!) 17:07:00 EST
+ Tag: blume-20020401-x86div
+ Description:
+ Added full support for div/mod/rem/quot on the x86, using the machine
+ instruction's two results (without clumsily recomputing the remainder)
+ directly where appropriate.
+ Some more extensive power-of-two support was added to the x86 instruction
+ selector (avoiding expensive divs, mods, and muls where they can be
+ replaced with cheaper shifts and masks).  However, this sort of thing
+ ought to be done earlier, e.g., within the CPS optimizer so that
+ all architectures benefit from it.
+ The compiler compiles to a fixed point, but changes might be somewhat
+ fragile nevertheless.  Please, report any strange things that you might
+ see wrt. div/mod/quot/rem...
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/29 17:22:00
+ Tag: blume-20020329-div
+ Description:
+ Fixed my broken div/mod logic.  Unfortunately, this means that the
+ inline code for div/mod now has one more comparison than before.
+ Fast paths (quotient > 0 or remainder = 0) are not affected, though.
+ The problem was with quotient = 0, because that alone does not tell
+ us which way the rounding went.  One then has to look at whether
+ remainder and divisor have the same sign...  :(
+ Anyway, I replaced the bootfiles with fresh ones...
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/29 14:10:00 EST
+ Tag: blume-20020329-inlprims
+ Description:
+ NEW BOOTFILES!!!    Version number bumped to 110.39.3.
+ Primops have changed. This means that the bin/boot-file formats have
+ changed as well.
+ To make sure that there is no confusion, I made a new version.
+ CHANGES:
+ * removed REMT from mltree (remainder should never overflow).
+ * added primops to deal with divisions of all flavors to the frontend
+ * handled these primops all the way through so they map to their respective
+   MLRISC support
+ * used these primops in the implementation of Int, Int32, Word, Word32
+ * removed INLDIV, INLMOD, and INLREM as they are no longer necessary
+ * parameterized INLMIN, INLMAX, and INLABS by a numkind
+ * translate.sml now deals with all flavors of INL{MIN,MAX,ABS}, including
+   floating point
+ * used INL{MIN,MAX,ABS} in the implementation of Int, Int32, Word, Word32,
+   and Real (but Real.abs maps to a separate floating-point-only primop)
+ TODO items:
+ * Hacked Alpha32 instruction selection, disabling the selection of REMx
+   instructions because the machine instruction encoder cannot handle
+   them.  (Hppa, PPC, and Sparc instruction selection did not handle
+   REM in the first place, and REM is supported by the x86 machine coder.)
+ * Handle DIV and MOD with DIV_TO_NEGINF directly in the x86 instruction
+   selection phase.  (The two can be streamlined because the hardware
+   delivers both quotient and remainder at the same time anyway.)
+ * Think about what to do with "valOf(Int32.minInt) div ~1" and friends.
+   (Currently the behavior is inconsistent both across architectures and
+   wrt. the draft Basis spec.)
+ * Word8 should eventually be handled natively, too.
+ * There seems to be one serious bug in mltree-gen.sml.  It appears, though,
+   as if there currently is no execution path that could trigger it in
+   SML/NJ.  (The assumptions underlying functions arith and promotable do not
+   hold for things like multiplication and division.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/27 16:27:00 EST
+ Tag: blume-20020327-mlrisc-divisions
+ Description:
+ Added support for all four division operations (ML's div, mod, quot,
+ and rem) to MLRISC.  In the course of doing so, I also rationalized
+ the naming (no more annoying switch-around of DIV and QUOT), by
+ parameterizing the operation by div_rounding_mode (which can be either
+ DIV_TO_ZERO or DIV_TO_NEGINF).
+ The generic MLTreeGen functor takes care of compiling all four
+ operations down to only round-to-zero div.
+ Missing pieces:
+   * Doing something smarter than relying on MLTreeGen on architectures
+     like, e.g., the x86 where hardware division delivers both quotient and
+     remainder at the same time.  With this, the implementation of the
+     round-to-neginf operations could be further streamlined.
+   * Remove inlining support for div/mod/rem from the frontend and replace it
+     with primops that get carried through to the backend.  Do this for all
+     int and word types.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/25 17:25:00 EST
+ Tag: blume-20020325-divmod
+ Description:
+ I improved (hopefully without breaking them) the implementation of Int.div,
+ Int.mod, and Int.rem.   For this, the code in translate.sml now takes
+ advantage of the following observations:
+   Let  q = x quot y      r = x rem y
+        d = x div  y      m = x mod y
+ where "quot" is the round-to-zero version of integer division that
+ hardware usually provides.  Then we have:
+      r = x - q * y        where neither the * nor the - will overflow
+      d = if q >= 0 orelse x = q * y then q else q - 1
+                           where neither the * nor the - will overflow
+      m = if q >= 0 orelse r = 0 then r else r + y
+                           where the + will not overflow
+ This results in substantial simplification of the generated code.
+ The following table shows the number of CFG nodes and edges generated
+ for
+         fun f (x, y) = x OPER y
+         (* with OPER \in div, mod, quot, rem *)
+     OPER | nodes(old) | edges(old) | nodes(new) | edges(new)
+     --------------------------------------------------------
+      div |         24 |         39 |         12 |         16
+      mod |         41 |         71 |         12 |         16
+     quot |          8 |         10 |          8 |         10
+      rem |         10 |         14 |          8 |         10
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/25 22:06:00 EST
+ Tag: blume-20020325-cprotobug
+ Description:
+ Fixed a bug in cproto (c prototype decoder).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/25 16:00:00 EST
+ Tag: blume-20020325-raw-primops
+ Description:
+ I did some cleanup to Allen's new primop code and
+ replaced yesterday's bootfiles with new ones.
+ (But they are stored in the same place.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/24 22:40:00 EST
+ Tag: blume-20020324-bootfiles
+ Description:
+ Made the bootfiles that Allen asked for.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/23 15:50:00 EST
+ Tag: leunga-20020323-flint-cps-rcc-primops
+ Description:
+. Changes to FLINT primops:
+     (* make a call to a C-function;
+      * The primop carries C function prototype information and specifies
+      * which of its (ML-) arguments are floating point. C prototype
+      * information is for use by the backend, ML information is for
+      * use by the CPS converter. *)
+   | RAW_CCALL of { c_proto: CTypes.c_proto,
+                    ml_args: ccall_type list,
+                    ml_res_opt: ccall_type option,
+                    reentrant : bool
+                  } option
+    (* Allocate uninitialized storage on the heap.
+     * The record is meant to hold short-lived C objects, i.e., they
+     * are not ML pointers.  With the tag, the representation is
+     * the same as RECORD with tag tag_raw32 (sz=4), or tag_fblock (sz=8)
+     *)
+   | RAW_RECORD of {tag:bool,sz:int}
+   and ccall_type = CCALL_INT32 | CCALL_REAL64 | CCALL_ML_PTR
+.  These CPS primops are now overloaded:
+        rawload of {kind:numkind}
+        rawstore of {kind:numkind}
+       The one argument form is:
+          rawload {kind} address
+       The two argument form is:
+          rawload {kind} [ml object, byte-offset]
+. RAW_CCALL/RCC now takes two extra arguments:
+      a. The first is whether the C call is reentrant, i.e., whether
+         ML state should be saved and restored.
+      b. The second argument is a string argument specifying the name of
+         library and the C function.
+      These things are currently not handled in the code generator, yet.
+. In CProto,
+      An encoding type of "bool" means "ml object" and is mapped into
+      C prototype of PTR.  Note that "bool" is different than "string",
+      even though "string" is also mapped into PTR, because "bool"
+      is assigned an CPS type of BOGt, while "string" is assigned INT32t.
+. Pickler/unpicker
+      Changed to handle RAW_RECORD and newest RAW_CCALL
+. MLRiscGen,
+. Changed to handle the new rawload/rawstore/rawrecord operators.
+. Code for handling C Calls has been moved to a new module CPSCCalls,
+         in the file CodeGen/cpscompile/cps-c-calls.sml
+. Added the conditional move operator
+          condmove of branch
+      to cps.  Generation of this is still buggy so it is currently
+      disabled.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/03/22 14:18:25 EST
+ Tag: george-20020322-cps-branch-prob
+ Description:
+ Implemented the Ball-Larus branch prediction-heuristics, and
+ incorporated graphical viewers for control flow graphs.
+ Ball-Larus Heuristics:
+ ---------------------
+ See the file compiler/CodeGen/cpscompile/cpsBranchProb.sml.
+ By design it uses the Dempster-Shafer theory for combining
+ probabilities.  For example, in the function:
+     fun f(n,acc) = if n = 0 then acc else f(n-1, n*acc)
+ the ball-larus heuristics predicts that the n=0 is unlikely
+ (OH-heuristic), and the 'then' branch is unlikely because of the
+ RH-heuristic -- giving the 'then' branch an even lower combined
+ probability using the Dempster-Shafer theory.
+ Finally, John Reppy's loop analysis in MLRISC, further lowers the
+ probability of the 'then' branch because of the loop in the else
+ branch.
+ Graphical Viewing:
+ ------------------
+ I merely plugged in Allen's graphical viewers into the compiler. The
+ additional code is not much. At the top level, saying:
+         Control.MLRISC.getFlag "cfg-graphical-view" := true;
+ will display the graphical view of the control flow graph just before
+ back-patching.  daVinci must be in your path for this to work. If
+ daVinci is not available, then the default viewer can be changed
+ using:
+         Control.MLRISC.getString "viewer"
+ which can be set to "dot" or "vcg" for the corresponding viewers. Of
+ course, these viewers must be in your path.
+ The above will display the compilation unit at the level of clusters,
+ many of which are small, boring, and un-interesting. Also setting:
+         Control.MLRISC.getInt "cfg-graphical-view_size"
+ will display clusters that are larger than the value set by the above.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/21 22:20:00 EST
+ Tag: blume-20020321-kmp-bugfix
+ Description:
+ Changed the interface to the KMP routine in PreString and fixed
+ a minor bug in one place where it was used.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/21 20:30:00 EST
+ Tag: leunga-20020321-cfg
+ Description:
+   Fixed a potential problem in cfg edge splitting.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/21 17:15:00 EST
+ Tag: leunga-20020321-x86-fp-cfg
+ Description:
+. Recoded the buggy parts of x86-fp.
+      a. All the block reordering code has been removed.
+         We now depend on the block placement phases to do this work.
+      b. Critical edge splitting code has been simplified and moved into the
+         CFG modules, as where they belong.
+      Both of these were quite buggy and complex.  The code is now much, much
+      simpler.
+. X86 backend.
+      a. Added instructions for 64-bit support.  Instruction selection for
+-bit has not been committed, however, since that
+         requires changes to MLTREE which haven't been approved by
+         Lal and John.
+      b. Added support for FUCOMI and FUCOMIP when generating code for
+         PentiumPro and above.  We only generate these instructions in
+         the fast-fp mode.
+      c. Added cases for JP and JNP in X86FreqProps.
+. CFG
+      CFG now has a bunch of methods for edge splitting and merging.
+. Machine description.
+      John's simplification of MLTREE_BASIS.fcond broke a few machine
+      description things:
+      rtl-build.{sig,sml} and hppa.mdl fixed.
+      NOTE: the machine description stuff in the repository is still broken.
+            Again, I can't put my fixes in because that involves
+            changes to MLTREE.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/20 15:55:00 EST
+ Tag: blume-20020320-kmp
+ Description:
+ Implemented Knuth-Morris-Pratt string matching in PreString and used
+ it for String.isSubstring, Substring.isSubstring, and
+ Substring.position.
+ (Might need some stress-testing.  Simple examples worked fine.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/19 16:37:00 EST
+ Tag: blume-20020319-witnesses
+ Description:
+ Added a structure C.W and functions convert/Ptr.convert to ml-nlffi-lib.
+ This implements a generic mechanism for changing constness qualifiers
+ anywhere within big C types without resorting to outright "casts".
+ (So far, functions such as C.rw/C.ro or C.Ptr.rw/C.Ptr.ro only let you
+ modify the constness at the outermost level.)
+ The implementation of "convert" is based on the idea of "witness"
+ values -- values that are not used by the operation but whose types
+ "testify" to their applicability.  On the implementation side, "convert"
+ is simply a projection (returning its second curried argument).  With
+ cross-module inlining, it should not result in any machine code being
+ generated.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/15 16:40:00 EST
+ Tag: blume-20020315-basis
+ Description:
+ Provided (preliminary?) implementations for
+   {String,Substring}.{concatWith,isSuffix,isSubstring}
+ and
+   Substring.full
+ Those are in the Basis spec but they were missing in SML/NJ.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/14 21:30:00 EST
+ Tag: blume-20020314-controls
+ Description:
+ Controls:
+ ---------
+. Factored out the recently-added Controls : CONTROLS stuff and put
+    it into its own library $/controls-lib.cm.  The source tree for
+    this is under src/smlnj-lib/Controls.
+. Changed the names of types and functions in this interface, so they
+    make a bit more "sense":
+       module -> registry
+       'a registry -> 'a group
+. The interface now deals in ref cells only.  The getter/setter interface
+    is (mostly) gone.
+. Added a function that lets one register an already-existing ref cell.
+. Made the corresponding modifications to the rest of the code so that
+    everything compiles again.
+. Changed the implementation of Controls.MLRISC back to something closer
+    to the original.  In particular, this module (and therefore MLRISC)
+    does not depend on Controls.  There now is some link-time code in
+    int-sys.sml that registers the MLRISC controls with the Controls
+    module.
+ CM:
+ ---
+   * One can now specify the lambda-split aggressiveness in init.cmi.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/13 17:30:00 EST
+ Tag: leunga-20020313-x86-fp-unary
+ Description:
+ Bug fix for:
+ > leunga@weaselbane:~/Yale/tmp/sml-dist{21} bin/sml
+ > Standard ML of New Jersey v110.39.1 [FLINT v1.5], March 08, 2002
+ > - fun f(x,(y,z)) = Real.~ y;
+ > [autoloading]
+ > [autoloading done]
+ >       fchsl   (%eax), 184(%esp)
+ > Error: MLRisc bug: X86MCEmitter.emitInstr
+ >
+ > uncaught exception Error
+ >   raised at: ../MLRISC/control/mlriscErrormsg.sml:16.14-16.19
+ The problem was that the code generator did not generate any fp registers
+ in this case, and the ra didn't know that it needed to run the X86FP phase to
+ translate the pseudo fp instruction.   This only happened with unary fp
+ operators in certain situations.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/13 14:00:00 EST
+ Tag: blume-20020313-overload-etc
+ Description:
+. Added _overload as a synonym for overload for backward compatibility.
+    (Control.overloadKW must be true for either version to be accepted.)
+. Fixed bug in install script that caused more things to be installed
+    than what was requested in config/targets.
+. Made CM aware of the (_)overload construct so that autoloading
+    works.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/12 22:03:00 EST
+ Tag: blume-20020312-url
+ Description:
+ Forgot to update BOOT and srcarchiveurl.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/12 17:30:00 EST
+ Tag: blume-20020312-version110392
+ Description:
+ Yet another version number bump (because of small changes to the
+ binfile format).  Version number is now 110.39.2.  NEW BOOTFILES!
+ Changes:
+   The new pid generation scheme described a few weeks ago was overly
+   complicated.  I implemented a new mechanism that is simpler and
+   provides a bit more "stability":  Once CM has seen a compilation
+   unit, it keeps its identity constant (as long as you do not delete
+   those crucial CM/GUID/* files).  This means that when you change
+   an interface, compile, then go back to the old interface, and
+   compile again, you arrive at the original pid.
+   There now also is a mechanism that instructs CM to use the plain
+   environment hash as a module's pid (effectively making its GUID
+   the empty string).  For this, "noguid" must be specified as an
+   option to the .sml file in question within its .cm file.
+   This is most useful for code that is being generated by tools such
+   as ml-nlffigen (because during development programmers tend to
+   erase the tool's entire output directory tree including CM's cached
+   GUIDs).  "noguid" is somewhat dangerous (since it can be used to locally
+   revert to the old, broken behavior of SML/NJ, but in specific cases
+   where there is no danger of interface confusion, its use is ok
+   (I think).
+   ml-nlffigen by default generates "noguid" annotations.  They can be
+   turned off by specifying -guid in its command line.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/03/12 12 14:42:36 EST
+ Tag: george-20020312-frequency-computation
+ Description:
+ Integrated jump chaining and static block frequency into the
+ compiler. More details and numbers later.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/03/11 11 22:38:53 EST
+ Tag: george-20020311-jump-chain-elim
+ Description:
+ Tested the jump chain elimination on all architectures (except the
+ hppa).  This is on by default right now and is profitable for the
+ alpha and x86, however, it may not be profitable for the sparc and ppc
+ when compiling the compiler.
+ The gc test will typically jump to a label at the end of the cluster,
+ where there is another jump to an external cluster containing the actual
+ code to invoke gc. This is to allow factoring of common gc invocation
+ sequences. That is to say, we generate:
+         f:
+            testgc
+            ja   L1      % jump if above to L1
+         L1:
+            jmp L2
+ After jump chain elimination the 'ja L1' instructions is converted to
+ 'ja L2'. On the sparc and ppc, many of the 'ja L2' instructions may end
+ up being implemented in their long form (if L2 is far away) using:
+         jbe     L3      % jump if below or equal to L3
+         jmp     L2
+      L3:
+         ...
+ For large compilation units L2  may be far away.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/11 13:30:00 EST
+ Tag: blume-20020311-mltreeeval
+ Description:
+ A functor parameter was missing.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/11 10:30:00 EST
+ Tag: leunga-20020311-runtime-string0
+ Description:
+    The representation of the empty string now points to a
+ legal null terminated C string instead of unit.  It is now possible
+ to convert an ML string into C string with InlineT.CharVector.getData.
+ This compiles into one single machine instruction.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/10 23:55:00 EST
+ Tag: leunga-20020310-x86-call
+ Description:
+    Added machine generation for CALL instruction (relative displacement mode)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/08 16:05:00
+ Tag: blume-20020308-entrypoints
+ Description:
+ Version number bumped to 110.39.1.  NEW BOOTFILES!
+ Entrypoints: non-zero offset into a code object where execution should begin.
+ - Added the notion of an entrypoint to CodeObj.
+ - Added reading/writing of entrypoint info to Binfile.
+ - Made runtime system bootloader aware of entrypoints.
+ - Use the address of the label of the first function given to mlriscGen
+   as the entrypoint.  This address is currently always 0, but it will
+   not be 0 once we turn on block placement.
+ - Removed the linkage cluster code (which was The Other Way(tm) of dealing
+   with entry points) from mlriscGen.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/07 20:45:00 EST
+ Tag: leunga-20020307-x86-cmov
+ Description:
+    Bug fixes for CMOVcc on x86.
+. Added machine code generation for CMOVcc
+. CMOVcc is now generated in preference over SETcc on PentiumPro or above.
+. CMOVcc cannot have an immediate operand as argument.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/03/07 16:15:00 EST
+ Tag: blume-20020307-controls
+ Description:
+ This is a very large but mostly boring patch which makes (almost)
+ every tuneable compiler knob (i.e., pretty much everything under
+ Control.* plus a few other things) configurable via both the command
+ line and environment variables in the style CM did its configuration
+ until now.
+ Try starting sml with '-h' (or, if you are brave, '-H')
+ To this end, I added a structure Controls : CONTROLS to smlnj-lib.cm which
+ implements the underlying generic mechanism.
+ The interface to some of the existing such facilities has changed somewhat.
+ For example, the MLRiscControl module now provides mkFoo instead of getFoo.
+ (The getFoo interface is still there for backward-compatibility, but its
+ use is deprecated.)
+ The ml-build script passes -Cxxx=yyy command-line arguments through so
+ that one can now twiddle the compiler settings when using this "batch"
+ compiler.
+ TODO items:
+ We should go through and throw out all controls that are no longer
+ connected to anything.  Moreover, we should go through and provide
+ meaningful (and correct!) documentation strings for those controls
+ that still are connected.
+ Currently, multiple calls to Controls.new are accepted (only the first
+ has any effect).  Eventually we should make sure that every control
+ is being made (via Controls.new) exactly once.  Future access can then
+ be done using Controls.acc.
+ Finally, it would probably be a good idea to use the getter-setter
+ interface to controls rather than ref cells.  For the time being, both
+ styles are provided by the Controls module, but getter-setter pairs are
+ better if thread-safety is of any concern because they can be wrapped.
+ *****************************************
+ One bug fix: The function blockPlacement in three of the MLRISC
+ backpatch files used to be hard-wired to one of two possibilities at
+ link time (according to the value of the placementFlag).  But (I
+ think) it should rather sense the flag every time.
+ *****************************************
+ Other assorted changes (by other people who did not supply a HISTORY entry):
+. the cross-module inliner now works much better (Monnier)
+. representation of weights, frequencies, and probabilities in MLRISC
+    changed in preparation of using those for weighted block placement
+    (Reppy, George)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/03/07 14:44:24 EST 2002
+ Tag: george-20020307-weighted-block-placement
+ Tested the weighted block placement optimization on all architectures
+ (except the hppa) using AMPL to generate the block and edge frequencies.
+ Changes were required in the machine properties to correctly
+ categorize trap instructions. There is an MLRISC flag
+ "weighted-block-placement" that can be used to enable weighted block
+ placement, but this will be ineffective without block/edge
+ frequencies (coming soon).
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/03/05 17:24:48 EST
+ Tag: george-20020305-linkage-cluster
+ In order to support the block placement optimization, a new cluster
+ is generated as the very first cluster (called the linkage cluster).
+ It contains a single jump to the 'real' entry point for the compilation
+ unit. Block placement has no effect on the linkage cluster itself, but
+ all the other clusters  have full freedom in the manner in which they
+ reorder blocks or functions.
+ On the x86 the typical linkage code that is generated is:
+    ----------------------
+         .align 2
+    L0:
+         addl    $L1-L0, 72(%esp)
+         jmp     L1
+         .align  2
+    L1:
+    ----------------------
+(%esp) is the memory location for the stdlink register. This
+ must contain the address of the CPS function being called. In the
+ above example, it contains the address of  L0; before
+ calling L1 (the real entry point for the compilation unit), it
+ must contain the address for L1, and hence
+         addl $L1-L0, 72(%esp)
+ I have tested this on all architectures except the hppa.The increase
+ in code size is of course negligible
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/03/03 13:20:00 EST
+ Tag: leunga-20020303-mlrisc-tools
+   Added #[ ... ] expressions to mlrisc tools
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/27 12:29:00 EST
+ Tag: blume-20020227-cdebug
+ Description:
+ - made types in structure C and C_Debug to be equal
+ - got rid of code duplication (c-int.sml vs. c-int-debug.sml)
+ - there no longer is a C_Int_Debug (C_Debug is directly derived from C)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/26 12:00:00 EST
+ Tag: blume-20020226-ffi
+ Description:
+. Fixed a minor bug in CM's "noweb" tool:
+    If numbering is turned off, then truly don't number (i.e., do not
+    supply the -L option to noweb).  The previous behavior was to supply
+    -L'' -- which caused noweb to use the "default" line numbering scheme.
+    Thanks to Chris Richards for pointing this out (and supplying the fix).
+. Once again, I reworked some aspects of the FFI:
+    A. The incomplete/complete type business:
+    - Signatures POINTER_TO_INCOMPLETE_TYPE and accompanying functors are
+      gone!
+    - ML types representing an incomplete type are now *equal* to
+      ML types representing their corresponding complete types (just like
+      in C).  This is still safe because ml-nlffigen will not generate
+      RTTI for incomplete types, nor will it generate functions that
+      require access to such RTTI.   But when ML code generated from both
+      incomplete and complete versions of the C type meet, the ML types
+      are trivially interoperable.
+      NOTE:  These changes restore the full generality of the translation
+      (which was previously lost when I eliminated functorization)!
+    B. Enum types:
+    - Structure C now has a type constructor "enum" that is similar to
+      how the "su" constructor works.  However, "enum" is not a phantom
+      type because each "T enum" has values (and is isomorphic to
+      MLRep.Signed.int).
+    - There are generic access operations for enum objects (using
+      MLRep.Signed.int).
+    - ml-nlffigen will generate a structure E_foo for each "enum foo".
+      * The structure contains the definition of type "mlrep" (the ML-side
+      representation type of the enum).  Normally, mlrep is the same
+      as "MLRep.Signed.int", but if ml-nlffigen was invoked with "-ec",
+      then mlrep will be defined as a datatype -- thus facilitating
+      pattern matching on mlrep values.
+      ("-ec" will be suppressed if there are duplicate values in an
+       enumeration.)
+      * Constructors ("-ec") or values (no "-ec") e_xxx of type mlrep
+      will be generated for each C enum constant xxx.
+      * Conversion functions m2i and i2m convert between mlrep and
+      MLRep.Signed.int.  (Without "-ec", these functions are identities.)
+      * Coversion functions c and ml convert between mlrep and "tag enum".
+      * Access functions (get/set) fetch and store mlrep values.
+    - By default (unless ml-nlffigen was invoked with "-nocollect"), unnamed
+      enumerations are merged into one single enumeration represented by
+      structure E_'.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/02/25 04:45:00 EST
+ Tag: leunga-20020225-cps-spill
+ This is a new implementation of the CPS spill phase.
+ The new phase is in the new file compiler/CodeGen/cpscompile/spill-new.sml
+ In case of problems, replace it with the old file spill.sml
+ The current compiler runs into some serious performance problems when
+ constructing a large record.  This can happen when we try to compile a
+ structure with many items.  Even a very simple structure like the following
+ makes the compiler slow down.
+     structure Foo = struct
+        val x_1 = 0w1 : Word32.int
+        val x_2 = 0w2 : Word32.int
+        val x_3 = 0w3 : Word32.int
+        ...
+        val x_N = 0wN : Word32.int
+     end
+ The following table shows the compile time, from N=1000 to N=4000,
+ with the old compiler:
+ N
+  CPS 100 spill                           0.04u  0.00s  0.00g
+        MLRISC ra                               0.06u  0.00s  0.05g
+           (spills = 0 reloads = 0)
+        TOTAL                                   0.63u  0.07s  0.21g
+  CPS 100 spill                           8.25u  0.32s  0.64g
+        MLRISC ra                               5.68u  0.59s  3.93g
+           (spills = 0 reloads = 0)
+        TOTAL                                   14.71u  0.99s  4.81g
+  CPS 100 spill                           58.55u  2.34s  1.74g
+        MLRISC ra                               5.54u  0.65s  3.91g
+           (spills = 543 reloads = 1082)
+        TOTAL                                   65.40u  3.13s  6.00g
+  CPS 100 spill                           126.69u  4.84s  3.08g
+        MLRISC ra                               0.80u  0.10s  0.55g
+           (spills = 42 reloads = 84)
+        TOTAL                                   129.42u  5.10s  4.13g
+  CPS 100 spill                           675.59u  19.03s  11.64g
+        MLRISC ra                               2.69u  0.27s  1.38g
+           (spills = 62 reloads = 124)
+        TOTAL                                   682.48u  19.61s  13.99g
+  CPS 100 spill                           2362.82u  56.28s  43.60g
+        MLRISC ra                               4.96u  0.27s  2.72g
+           (spills = 85 reloads = 170)
+        TOTAL                                   2375.26u  57.21s  48.00g
+ As you can see the old cps spill module suffers from some serious
+ performance problem.  But since I cannot decipher the old code fully,
+ instead of patching the problems up, I'm reimplementing it
+ with a different algorithm.  The new code is more modular,
+ smaller when compiled, and substantially faster
+ (O(n log n) time and O(n) space).  Timing of the new spill module:
+ CPS 100 spill                           0.02u  0.00s  0.00g
+       MLRISC ra                               0.25u  0.02s  0.15g
+          (spills=1 reloads=3)
+       TOTAL                                   7.74u  0.34s  1.62g
+ Implementation details:
+ As far as I can tell, the purpose of the CPS spill module is to make sure the
+ number of live variables at any program point (the bandwidth)
+ does not exceed a certain limit, which is determined by the
+ size of the spill area.
+ When the bandwidth is too large, we decrease the register pressure by
+ packing live variables into spill records.  How we achieve this is
+ completely different than what we did in the old code.
+ First, there is something about the MLRiscGen code generator
+ that we should be aware of:
+ o MLRiscGen performs code motion!
+    In particular, it will move floating point computations and
+    address computations involving only the heap pointer to
+    their use sites (if there is only a single use).
+    What this means is that if we have a CPS record construction
+    statement
+        RECORD(k,vl,w,e)
+    we should never count the new record address w as live if w
+    has only one use (which is often the case).
+    We should do something similar to floating point, but the transformation
+    there is much more complex, so I won't deal with that.
+ Secondly, there are now two new cps primops at our disposal:
+. rawrecord of record_kind option
+     This pure operator allocates some uninitialized storage from the heap.
+     There are two forms:
+      rawrecord NONE [INT n]  allocates a tagless record of length n
+      rawrecord (SOME rk) [INT n] allocates a tagged record of length n
+                                  and initializes the tag.
+. rawupdate of cty
+       rawupdate cty (v,i,x)
+       Assigns to x to the ith component of record v.
+       The storelist is not updated.
+ We use these new primops for both spilling and increment record construction.
+. Spilling.
+     This is implemented with a linear scan algorithm (but generalized
+     to trees).  The algorithm will create a single spill record at the
+     beginning of the cps function and use rawupdate to spill to it,
+     and SELECT or SELp to reload from it.  So both spills and reloads
+     are fine-grain operations.  In contrast, in the old algorithm
+     "spills" have to be bundled together in records.
+     Ideally, we should sink the spill record construction to where
+     it is needed.  We can even split the spill record into multiple ones
+     at the places where they are needed.  But CPS is not a good
+     representation for global code motion, so I'll keep it simple and
+     am not attempting this.
+. Incremental record construction (aka record splitting).
+     Long records with many component values which are simulatenously live
+     (recall that single use record addresses are not considered to
+      be live) are constructed with rawrecord and rawupdate.
+     We allocate space on the heap with rawrecord first, then gradually
+     fill it in with rawupdate.  This is the technique suggested to me
+     by Matthias.
+     Some restrictions on when this is applicable:
+. It is not a VECTOR record.  The code generator currently does not handle
+        this case. VECTOR record uses double indirection like arrays.
+. All the record component values are defined in the same "basic block"
+        as the record constructor.  This is to prevent speculative
+        record construction.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/02/22 01:02:00 EST
+ Tag: leunga-20020222-mlrisc-tools
+ Minor bug fixes in the parser and rewriter
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/02/21 20:20:00 EST
+ Tag: leunga-20020221-peephole
+ Regenerated the peephole files.  Some contained typos in the specification
+ and some didn't compile because of pretty printing bugs in the old version
+ of 'nowhere'.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/02/19 20:20:00 EST
+ Tag: leunga-20020219-mlrisc-tools
+ Description:
+    Minor bug fixes to the mlrisc-tools library:
+.  Fixed up parsing colon suffixed keywords
+.  Added the ability to shut the error messages up
+.  Reimplemented the pretty printer and fixed up/improved
+        the pretty printing of handle and -> types.
+.  Fixed up generation of literal symbols in the nowhere tool.
+.  Added some SML keywords to to sml.sty
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/19 16:20:00 EST
+ Tag: blume-20020219-cmffi
+ Description:
+ A wild mix of changes, some minor, some major:
+ * All C FFI-related libraries are now anchored under $c:
+     $/c.cm      --> $c/c.cm
+     $/c-int.cm  --> $c/internals/c-int.cm
+     $/memory.cm --> $c/memory/memory.cm
+ * "make" tool (in CM) now treats its argument pathname slightly
+   differently:
+. If the native expansion is an absolute name, then before invoking
+        the "make" command on it, CM will apply OS.Path.mkRelative
+        (with relativeTo = OS.FileSys.getDir()) to it.
+. The argument will be passed through to subsequent phases of CM
+        processing without "going native".  In particular, if the argument
+        was an anchored path, then "make" will not lose track of that anchor.
+ * Compiler backends now "know" their respective C calling conventions
+   instead of having to be told about it by ml-nlffigen.  This relieves
+   ml-nlffigen from one of its burdens.
+ * The X86Backend has been split into X86CCallBackend and X86StdCallBackend.
+ * Export C_DEBUG and C_Debug from $c/c.cm.
+ * C type encoding in ml-nlffi-lib has been improved to model the conceptual
+   subtyping relationship between incomplete pointers and their complete
+   counterparts.  For this, ('t, 'c) ptr has been changed to 'o ptr --
+   with the convention of instantiating 'o with ('t, 'c) obj whenever
+   the pointer target type is complete.  In the incomplete case, 'o
+   will be instantiated with some "'c iobj" -- a type obtained by
+   using one of the functors PointerToIncompleteType or PointerToCompleteType.
+   Operations that work on both incomplete and complete pointer types are
+   typed as taking an 'o ptr while operations that require the target to
+   be known are typed as taking some ('t, 'c) obj ptr.
+   voidptr is now a bit "more concrete", namely "type voidptr = void ptr'"
+   where void is an eqtype without any values.  This makes it possible
+   to work on voidptr values using functions meant to operate on light
+   incomplete pointers.
+ * As a result of the above, signature POINTER_TO_INCOMPLETE_TYPE has
+   been vastly simplified.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/19 10:48:00 EST
+ Tag: blume-20020219-pqfix
+ Description:
+ Applied Chris Okasaki's bug fix for priority queues.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/15 17:05:00
+ Tag: Release_110_39
+ Description:
+ Last-minute retagging is becoming a tradition... :-(
+ This is the working release 110.39.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/15 16:00:00 EST
+ Tag: Release_110_39-orig
+ Description:
+ Working release 110.39.  New bootfiles.
+ (Update: There was a small bug in the installer so it wouldn't work
+ with all shells.  So I retagged. -Matthias)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/15 14:17:00 EST
+ Tag: blume-20020215-showbindings
+ Description:
+ Added EnvRef.listBoundSymbols and CM.State.showBindings.  Especially
+ the latter can be useful for exploring what bindings are available at
+ the interactive prompt.  (The first function returns only the list
+ of symbols that are really bound, the second prints those but also the
+ ones that CM's autoloading mechanism knows about.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/15 12:08:00 EST
+ Tag: blume-20020215-iptrs
+ Description:
+ Two improvements to ml-nlffigen:
+. Write files only if they do not exist or if their current contents
+      do not coincide with what's being written.  (That is, avoid messing
+      with the time stamps unless absolutely necessary.)
+. Implement a "repository" mechanism for generated files related
+      to "incomplete pointer types".   See the README file for details.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/14 11:50:00 EST
+ Tag: blume-20020214-quote
+ Description:
+ Added a type 't t_' to tag.sml (in ml-nlffi-lib.cm).  This is required
+ because of the new and improved tag generation scheme.  (Thanks to Allen
+ Leung for pointing it out.)
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/02/14 09:55:27 EST 2002
+ Tag: george-20020214-isabelle-bug
+ Description:
+ Fixed the MLRISC bug sent by Markus Wenzel regarding the compilation
+ of Isabelle on the x86.
+ From Allen:
+ -----------
+  I've found the problem:
+      in ra-core.sml, I use the counter "blocked" to keep track of the
+      true number of elements in the freeze queue.  When the counter goes
+      to zero, I skip examining the queue.  But I've messed up the
+      bookkeeping in combine():
+          else ();
+          case !ucol of
+            PSEUDO => (if !cntv > 0 then
+                  (if !cntu > 0 then blocked := !blocked - 1 else ();
+                                     ^^^^^^^^^^^^^^^^^^^^^^^
+                   moveu := mergeMoveList(!movev, !moveu)
+                  )
+               else ();
+      combine() is called to coalesce two nodes u and v.
+      I think I was thinking that if the move counts of u and v are both
+      greater than zero then after they are coalesced then one node is
+      removed from the freeze queue.  Apparently I was thinking that
+      both u and v are of low degree, but that's clearly not necessarily true.
+/12/2002:
+     Here's the patch.  HOL now compiles.
+     I don't know how this impact on performance (compile
+     time or runtime).  This bug caused the RA (especially on the x86)
+     to go thru the potential spill phase when there are still nodes on the
+     freeze queue.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/13 22:40:00 EST
+ Tag: blume-20020213-fptr-rtti
+ Description:
+ Fixed a bug in ml-nlffigen that was introduced with one of the previous
+ updates.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/13 16:41:00 EST
+ Tag: blume-20020213-cmlpq
+ Description:
+ Added new priority queue export symbols (which have just been added to
+ smlnj-lib.cm) to CML's version of smlnj-lib.cm.  (Otherwise CML would
+ not compile and the installer would choke.)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/13 16:15:00 EST
+ Tag: blume-20020213-various
+ Description:
+. More tweaks to ml-nlffigen:
+    - better internal datastructures (resulting in slight speedup)
+    - "-match" option requires exact match
+    - "localized" gensym counters (untagged structs/unions nested within
+      other structs/unions or within typedefs get a fresh counter; their
+      tag will be prefixed by a concatenation of their parents' tags)
+    - bug fixes (related to calculation of transitive closure of types
+      to be included in the output)
+. Minor Basis updates:
+    - added implementations for List.collate and Option.app
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/11 15:55:00 EST
+ Tag: blume-20020211-gensym
+ Description:
+ Added a "-gensym" option to command line of ml-nlffigen.  This can be
+ used to specify a "stem" -- a string that is inserted in all "gensym'd"
+ names (ML structure names that correspond to unnamed C structs, unions,
+ and enums), so that separate runs of ml-nlffigen do not clash.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/11 12:05:00 EST
+ Tag: blume-20020211-gensml
+ Description:
+ A quick fix for a problem with GenSML (in the pgraph-util library):
+ Make generation of toplevel "local" optional.  (Strictly speaking,
+ signature definitions within "local" are not legal SML.)
+ Other than that: updates to INSTALL and cm/TODO.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/02/08 15:00:00 EST
+ Tag: blume-20020208-uniquepid
+ Description:
+. Version number has been bumped to 110.38.1.  NEW BOOTFILES!!!
+. The installer (config/install.sh) has gotten smarter:
+      - Configuration options are a bit easier to specify now
+        (in config/targets).
+      - Bug in recognizing .tar.bz2 files fixed.
+      - Installer automatically resolves dependencies between
+        configuration options (e.g., if you ask for eXene, you will
+        also get cml -- regardless whether you asked for it or not).
+      - Installer can run in "quieter mode" by setting the environment
+        variable INSTALL_QUIETLY to "true".  "Quieter" does not mean
+        "completely silent", though.
+      - Build HashCons library as part of smlnj-lib.
+. A new scheme for assigning persistent identifiers to compilation
+    units (and, by extension, to types etc.) has been put into place.
+    This fixes a long-standing bug where types and even dynamic values
+    can get internally confused, thereby compromising type safety
+    (abstraction) and dynamic correctness.  See
+      http://cm.bell-labs.com/cm/cs/who/blume/pid-confusion.tgz
+    for an example of how things could go wrong until now.
+    The downside of the new scheme is that pids are not quite as
+    persistent as they used to be: CM will generate a fresh pid
+    for every compilation unit that it thinks it sees for the first
+    time.  That means that if you compile starting from a clean, fresh
+    source tree at two different times, you end up with different
+    binaries.
+    Cutoff recompilation, however, has not been compromised because
+    CM keeps pid information in special caches between runs.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/02/07 15:34:13 EST 2002
+ Tag: <none>
+ Description:
+ Compilers that generate assembly code may produce  global labels
+ whose value is resolved at link time. The various peephole optimization
+ modules did not take this in account.
+ TODO. The Labels.addrOf function should really return an option
+ type so that clients are forced to deal with this issue, rather
+ than an exception being raised.
+ ----------------------------------------------------------------------
+ Name: Lal George
+ Date: 2002/02/06 13:55:02 EST
+ Tag: george-20020206-ra-breakup
+ Description:
+. A bug fix from Allen.
+     A typo causes extra fstp %st(0)'s to be generated at compensation
+     edges, which might cause stack underflow traps at runtime.  This
+     occurs in fft where there are extraneous fstps right before the 'into'
+     trap instruction (in this case they are harmless since none of the
+     integers overflow.)
+. Pulled out various utility modules that were embedded in the modules
+    of the register allocator. I need these modules for other purposes, but
+    they are not complete enough to put into a library (just yet).
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/31 16:05:00 EST
+ Tag: blume-20020131-sparc-ccalls
+ Description:
+. C-calls on Sparc needlessly allocated a huge chunk (96 bytes)
+    of extra stack space by mistake.  Fixed.
+. Bug in logic of handling of command-line options in ml-nlffigen fixed.
+ ----------------------------------------------------------------------
+ Name: Allen Leung
+ Date: 2002/01/30
+ Tag: leunga-20020130-nowhere-bug-fix
+ Description:
+    MLRISC bug fixes:
+. Fixed a bindings computation bug in the 'nowhere' program generator tool.
+. MachineInt.fromString was negating its value.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/29
+ Tag: blume-20020129-INSTALL
+ Description:
+ - Added somewhat detailed installation instructions (file INSTALL).
+ - Fixed curl-detection bug in config/install.sh.
+ - It is now possible to select the URL getter using the URLGETTER
+   environment variable:
+       not set / "unknown"      --> automatic detection (script tries wget,
+                                    curl, and lynx)
+       "wget" / "curl" / "lynx" --> use the specified program (script "knows"
+                                    how to properly invoke them)
+       other                    --> use $URLGETTER directly, it must take
+                                    precisely two command-line arguments
+                                    (source URL and destination file name)
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/28
+ Tag: blume-20020128-sparc-ccalls
+ Description:
+ - Fixed problem with calculation of "used" registers in sparc-c-calls.
+ - Make use of the allocParam argument in sparc-c-calls.
+ ----------------------------------------------------------------------
+ Name: Matthias Blume
+ Date: 2002/01/28
+ Tag: blume-20020128-allocParam
+ Description:
+ John Reppy:  Changes c-calls API to accept client-callback for
+ allocating extra stack space.
+ me: Corresponding changes to mlriscGen (using a dummy argument that
+     does not change the current behavior).
+ ----------------------------------------------------------------------
+ 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
+ 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.