It was used only in cases where a lock field needed to be added to a
run-time variable, like e.g. in examples/phrasebook/SentencesTha.gf:
lin
PGreetingMale g = mkText (lin Text g) (lin Text (ss "ครับ")) | g ;
PGreetingFemale g = mkText (lin Text g) (lin Text (ss "ค่ะ")) | g ;
But lock fields are only meaningful during type checking and can safely be
ignored in later passes.
On my laptop these changes speed up the full build of the RGL and example
grammars with 'cabal build' from ~95s to ~43s and the zero build from ~18s
to ~5s.
The main change is the introduction of the module GF.CompileInParallel that
replaces GF.Compile and the function GF.Compile.ReadFiles.getAllFiles. At
present, it is activated with the new -j flag, and it is only used when
combined with --make or --batch. In addition, to get parallel computations,
you need to add GHC run-time flags, e.g., +RTS -N -A20M -RTS, to the command
line.
The Setup.hs script has been modified to pass the appropriate flags to GF
for parallel compilation when compiling the RGL and example grammars, but you
need a recent version of Cabal for this to work (probably >=1.20).
Some additonal refactoring were made during this work. A new monad is used to
avoid warnings/error messages from different modules to be intertwined when
compiling in parallel, so some functios that were hardiwred to the IO or IOE
monads have been lifted to work in arbitrary monads that are instances in
the appropriate classes.
GF.Text.Pretty provides the class Pretty and overloaded versions of the pretty
printing combinators in Text.PrettyPrint, allowing pretty printable values to
be used directly instead of first having to convert them to Doc with functions
like text, int, char and ppIdent. Some modules have been converted to use
GF.Text.Pretty, but not all. Precedences could be added to simplify the pretty
printers for terms and patterns.
GF.Infra.Location contains the types Location and L, factored out from
GF.Grammar.Grammar, and the class HasSourcePath. This allowed the import
of GF.Grammar.Grammar to be removed from GF.Infra.CheckM, making it more
like a pure library module.
PGF exports the public, stable API.
PGF.Internal exports additional things needed in the GF compiler & shell,
including the nonstardard version of Data.Binary.
Eta expansion is applied between partial evaluation and PMCFG generation.
The buggy version generated type incorrect terms, but PMCFG generation
apparently worked anyway.
This bug was introduced sometime between 2013-08-21 and 2013-11-01 and caused
the function convertTerm in GF.Compile.GeneratePMCFG to encounter a EPatt where
it expected Strs. I fixed it by applying the function getPatts (from the old
partial evaluator) to the pattern.
This means that the -old-comp and -new-comp flags are not recognized anymore.
The only functional difference is that printnames were still normalized with
the old partial evaluator. Now that is done with the new partial evaluator.
+ Eliminated vairous ad-hoc coersion functions between specific monads
(IO, Err, IOE, Check) in favor of more general lifting functions
(liftIO, liftErr).
+ Generalized many basic monadic operations from specific monads to
arbitrary monads in the appropriate class (MonadIO and/or ErrorMonad),
thereby completely eliminating the need for lifting functions in lots
of places.
This can be considered a small step forward towards a cleaner
compiler API and more malleable compiler code in general.
+ References to modules under src/compiler have been eliminated from the PGF
library (under src/runtime/haskell). Only two functions had to be moved (from
GF.Data.Utilities to PGF.Utilities) to make this possible, other apparent
dependencies turned out to be vacuous.
+ In gf.cabal, the GF executable no longer directly depends on the PGF library
source directory, but only on the exposed library modules. This means that
there is less duplication in gf.cabal and that the 30 modules in the
PGF library will no longer be compiled twice while building GF.
To make this possible, additional PGF library modules have been exposed, even
though they should probably be considered for internal use only. They could
be collected in a PGF.Internal module, or marked as "unstable", to make
this explicit.
+ Also, by using the -fwarn-unused-imports flag, ~220 redundant imports were
found and removed, reducing the total number of imports by ~15%.
The following are the outcomes:
- Predef.nonExist is fully supported by both the Haskell and the C runtimes
- Predef.BIND is now an internal compiler defined token. For now
it behaves just as usual for the Haskell runtime, i.e. it generates &+.
However, the special treatment will let us to handle it properly in
the C runtime.
- This required a major change in the PGF format since both
nonExist and BIND may appear inside 'pre' and this was not supported
before.
Most of the explicit uses of ByteStrings were eliminated by using identS,
identS = identC . BS.pack
which was found in GF.Grammar.CF and moved to GF.Infra.Ident. The function
prefixIdent :: String -> Ident -> Ident
allowed one additional import of ByteString to be eliminated. The functions
isArgIdent :: Ident -> Bool
getArgIndex :: Ident -> Maybe Int
were needed to eliminate explicit pattern matching on Ident from two modules.
+ Instead of "Internal error in ...", you now get a proper error message with
a source location and a function name.
+ Also added some missing error value propagation in the partial evaluator.
+ Also some other minor cleanup and error handling fixes.
The work done by the partial evaluator is now divied in two stages:
- A static "term traversal" stage that happens only once per term and uses
only statically known information. In particular, the values of lambda bound
variables are unknown during this stage. Some tables are transformed to
reduce the cost of pattern matching.
- A dynamic "function application" stage, where function bodies can be
evaluated repeatedly with different arguments, without the term traversal
overhead and without recomputing statically known information.
Also the treatment of predefined functions has been reworked to take advantage
of the staging and better handle partial applications.
* Evaluate operators once, not every time they are looked up
* Remember the list of parameter values instead of recomputing it from the
pattern type every time a table selection is made.
* Quick fix for partial application of some predefined functions.
GF.Compile.Compute.ConcreteNew + two new modules contain a new
partial evaluator intended to solve some performance problems with the old
partial evalutator in GF.Compile.Compute.ConcreteLazy. It has been around for
a while, but is now complete enough to compile the RGL and the Phrasebook.
The old partial evaluator is still used by default. The new one can be activated
in two ways:
- by using the command line option -new-comp when invoking GF.
- by using cabal configure -fnew-comp to make -new-comp the default. In this
case you can also use the command line option -old-comp to revert to the old
partial evaluator.
In the GF shell, the cc command uses the old evaluator regardless of -new-comp
for now, but you can use "cc -new ..." to invoke the new evaluator.
With -new-comp, computations happen in GF.Compile.GeneratePMCFG instead of
GF.Compile.Optimize. This is implemented by testing the flag optNewComp in
both modules, to omit calls to the old partial evaluator from GF.Compile.Optimize
and add calls to the new partial evaluator in GF.Compile.GeneratePMCFG.
This also means that -new-comp effectively implies -noexpand.
In GF.Compile.CheckGrammar, there is a check that restricted inheritance is used
correctly. However, when -noexpand is used, this check causes unexpected errors,
so it has been converted to generate warnings, for now.
-new-comp no longer enables the new type checker in
GF.Compile.Typeckeck.ConcreteNew.
The GF version number has been bumped to 3.3.10-darcs
An apparent bug in ghc-7.2.2 causes the type Value to be exported from PGF.Data.
Workaround: restrict the imports from PGF.Data in GF.Command.Abstract and
GF.Compile.GeneratePMCFG to avoid the clash with locally defined type Value.
(ghc-7.0.4 and ghc-7.4.1 appear to be free from this bug.)
