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"project.name" : "nofib",
"repository.callsign" : "NOFIB",
"phabricator.uri" : "https://phabricator.haskell.org"
# Generated file patterns
# Specific generated files
......@@ -22,12 +29,20 @@ imaginary/tak/tak
......@@ -38,7 +53,8 @@ real/hidden/hidden
......@@ -50,10 +66,39 @@ real/scs/scs
......@@ -64,7 +109,9 @@ spectral/constraints/constraints
......@@ -87,10 +134,13 @@ spectral/hartel/wang/wang
......@@ -117,6 +167,7 @@ gc/mutstore1/mutstore1
DOCKER_REV: 2b69e99de97bd5bf1fbdbf45852231c3dcb602b6
image: "registry.gitlab.haskell.org/ghc/ci-images/x86_64-linux-deb9:$DOCKER_REV"
- x86_64-linux
- git clean -xdf
- sudo apt install -y time
- ghc --version
- cabal --version
- make clean
- cabal update
- make boot mode=fast
- "make mode=fast NoFibRuns=1 2>&1 | tee log"
- "nofib-analyse/nofib-analyse log"
- |
# The following checks that `make distclean` removes any files reported
# by `git clean -fxd`
make distclean
files=$(git clean -nxd | cut -d" " -f3 | sed "/log/d")
if ! [ -z $files ]
echo "The following files weren't cleaned:\n$files"
exit 1
# Syntax: https://docs.gitlab.com/ee/user/project/code_owners.html
* @sgraf812 @bgamari
\ No newline at end of file
......@@ -28,7 +28,7 @@ SUBDIRS = runstdtest nofib-analyse $(NoFibSubDirs)
SRC_DIST_DIR=$(shell pwd)/nofib
SRC_DIST_DIRS=docs fibon gc imaginary smp spectral real parallel mk
SRC_DIST_DIRS=docs fibon gc imaginary smp spectral real parallel mk shootout
dist :: nofib-dist-pre
include $(TOP)/mk/target.mk
This is the root directory of the "NoFib Haskell benchmark suite". It
should be part of a GHC source tree, that is the 'nofib' directory
should be at the same level in the tree as 'compiler' and 'libraries'.
To run the tests:
$ make clean
$ make boot
$ make 2>&1 | tee nofib-log
will put the results in the file 'nofib-log'. You can pass extra options to a
nofib run using the EXTRA_HC_OPTS variable like this:
$ make clean
$ make boot
$ make EXTRA_HC_OPTS="-fllvm" >&1 | tee nofib-llvm-log
To compare the results of multiple runs, use the program in
../utils/nofib-analyse. Something like this:
$ nofib-analyse nofib-log-6.4.2 nofib-log-6.6
to generate a comparison of the runs in captured in 'nofib-log-6.4.2'
and 'nofib-log-6.6'. When making comparisons, be careful to ensure
that the things that changed between the builds are only the things
that you *wanted* to change. There are lots of variables: machine,
GHC version, GCC version, C libraries, static vs. dynamic GMP library,
build options, run options, and probably lots more. To be on the safe
side, make both runs on the same unloaded machine.
To get instruction counts, memory reads/writes, and "cache misses",
you'll need to get hold of Cachegrind, which is part of Valgrind
There are some options you might want to tweak; search for nofib in
../mk/config.mk, and override settings in ../mk/build.mk as usual.
Package Requirements:
* html
* regex-compat (mtl, regex-base, regex-posix)
* stm (for smp benches)
# NoFib: Haskell Benchmark Suite
This is the root directory of the "NoFib Haskell benchmark suite". It
should be part of a GHC source tree, that is the 'nofib' directory
should be at the same level in the tree as 'compiler' and 'libraries'.
This makes sure that NoFib picks up the stage 2 compiler from the
surrounding GHC source tree.
You can also clone this repository in isolation, in which case it will
pick `$(which ghc)` or whatever the `HC` environment variable is set to.
Additional information can also be found on
[NoFib's wiki page](https://ghc.haskell.org/trac/ghc/wiki/Building/RunningNoFib).
There's also a `easy.sh` helper script, which as name implies, is
automated and easy way to run `nofib`.
See the section at the end of README for its usage.
## Using
<summary>Git symlink support for Windows machines</summary>
NoFib uses a few symlinks here and there to share code between benchmarks.
Git for Windows has symlinks support for some time now, but
[it may not be enabled by default](https://stackoverflow.com/a/42137273/388010).
You will notice strange `make boot` failures if it's not enabled for you.
Make sure you follow the instructions in the link to enable symlink support,
possibly as simple as through `git config core.symlinks true` or cloning with
`git clone -c core.symlinks=true <URL>`.
Install [`cabal-install-2.4`](https://www.haskell.org/cabal/download.html) or later.
Then, to run the tests, execute:
$ make clean # or git clean -fxd, it's faster
$ # Generates input files for the benchmarks and builds compilation
$ # dependencies for make (ghc -M)
$ make boot
$ # Builds the benchmarks and runs them $NoFibRuns (default: 5) times
$ make
This will put the results in the file `nofib-log`. You can pass extra
options to a nofib run using the `EXTRA_HC_OPTS` variable like this:
$ make clean
$ make boot
$ make EXTRA_HC_OPTS="-fllvm"
**Note:** to get all the results, you have to `clean` and `boot` between
separate `nofib` runs.
To compare the results of multiple runs, save the output in a logfile
and use the program in `./nofib-analyse/nofib-analyse`, for example:
$ make 2>&1 | tee nofib-log-6.4.2
$ make 2>&1 | tee nofib-log-6.6
$ nofib-analyse nofib-log-6.4.2 nofib-log-6.6 | less
to generate a comparison of the runs in captured in `nofib-log-6.4.2`
and `nofib-log-6.6`. When making comparisons, be careful to ensure
that the things that changed between the builds are only the things
that you _wanted_ to change. There are lots of variables: machine,
GHC version, GCC version, C libraries, static vs. dynamic GMP library,
build options, run options, and probably lots more. To be on the safe
side, make both runs on the same unloaded machine.
## Modes
Each benchmark is runnable in three different time `mode`s:
- `fast`: 0.1-0.2s
- `norm`: 1-2s
- `slow`: 5-10s
You can control which mode to run by setting an additional `mode` variable for
`make`. The default is `mode=norm`. Example for `mode=fast`:
$ make clean
$ make boot mode=fast
$ make mode=fast
Note that the `mode`s set in `make boot` and `make` need to agree. Otherwise you
will get output errors, because `make boot` will generate input files for a
different `mode`. A more DRY way to control the `mode` would be
$ make clean
$ export mode=fast
$ make boot
$ make
As CPU architectures advance, the above running times may drift and
occasionally, all benchmarks will need adjustments.
Be aware that `nofib-analyse` will ignore the result if it falls below 0.2s.
This is the default of its `-i` option, which is of course incompatible with
`mode=fast`. In that case, you should just set `-i` as appropriate, even
deactivate it with `-i 0`.
## Boot vs. benchmarked GHC
The `nofib-analyse` utility is compiled with `BOOT_HC` compiler,
which may be different then the GHC under the benchmark.
You can control which GHC you benchmark with `HC` variable
$ make clean
$ make boot HC=ghc-head
$ make HC=ghc-head 2>&1 | tee nofib-log-ghc-head
## Configuration
There are some options you might want to tweak; search for nofib in
`../mk/config.mk`, and override settings in `../mk/build.mk` as usual.
## Extra Metrics: Valgrind
To get instruction counts, memory reads/writes, and "cache misses",
you'll need to get hold of Cachegrind, which is part of
You can then pass `-cachegrind` as `EXTRA_RUNTEST_OPTS`. Counting
instructions slows down execution by a factor of ~30. But it's
a deterministic metric, so you can combine it with `NoFibRuns=1`:
$ (make EXTRA_RUNTEST_OPTS="-cachegrind" NoFibRuns=1) 2>&1 | tee nofib-log
Optionally combine this with `mode=fast`, see [Modes](#modes).
## Extra Packages
Some benchmarks aren't run by default and require extra packages are
installed for the GHC compiler being tested. These packages include:
* `old-time`: for `gc` benchmarks
* `stm`: for smp benchmarks
* `parallel`: for parallel benchmarks
* `random`: for various benchmarks
These can be installed with
cabal v1-install --allow-newer -w $HC random parallel old-time
## Adding benchmarks
If you add a benchmark try to set the problem sizes for
fast/normal/slow reasonably. [Modes](#modes) lists the recommended brackets for
each mode.
### Benchmark Categories
So you have a benchmark to submit but don't know in which subfolder to put it? Here's some
advice on the intended semantics of each category.
#### Single threaded benchmarks
These are run when you just type `make`. Their semantics is explained in
[the Nofib paper](https://link.springer.com/chapter/10.1007%2F978-1-4471-3215-8_17)
(You can find a .ps online, thanks to @bgamari. Alternatively grep for
'Spectral' in docs/paper/paper.verb).
- `imaginary`: Mostly toy benchmarks, solving puzzles like n-queens.
- `spectral`: Algorithmic kernels, like FFT. If you want to add a benchmark of a
library, this most certainly the place to put it.
- `real`: Actual applications, with a command-line interface and all. Because of
the large dependency footprint of today's applications, these have become
rather aged.
- `shootout`: Benchmarks from
[the benchmarks game](https://benchmarksgame-team.pages.debian.net/benchmarksgame/),
formerly known as "language shootout".
Most of the benchmarks are quite old and aren't really written in way one would
write high-performance Haskell code today (e.g., use of `String`, lists,
redefining own list combinators that don't take part in list fusion, rare use of
strictness annotations or unboxed data), so new benchmarks for the `real` and
`spectral` in brackets in particular are always welcome!
#### Other categories
Other than the default single-threaded categories above, there are the
following (SG: I'm guessing here, have never run them):
- `gc`: Run by `make -C gc` (though you'll probably have to edit the Makefile to
your specific config). Select benchmarks from `spectral` and `real`, plus a
few more (Careful, these have not been touched by #15999/!5, see the next
subsection). Testdrives different GC configs, apparently.
- `smp`: Microbenchmarks for the `-threaded` runtime, measuring scheduler
performance on concurrent and STM-heavy code.
### Stability wrt. GC paramerisations
Additionally, pay attention that your benchmarks are stable wrt. different
GC paramerisations, so that small changes in allocation don't lead to big,
unexplicable jumps in performance. See #15999 for details. Also make sure
that you run the benchmark with the default GC settings, as enlarging Gen 0 or
Gen 1 heaps just amplifies the problem.
As a rule of thumb on how to ensure this: Make sure that your benchmark doesn't
just build up one big data and consume it in a final step, but rather that the
working set grows and shrinks (e.g. is approximately constant) over the whole
run of the benchmark. You can ensure this by iterating your main logic `$n`
times (how often depends on your program, but in the ball park of 100-1000).
You can test stability by plotting productivity curves for your `fast` settings
with the `prod.py` script attached to #15999.
If in doubt, ask Sebastian Graf for help.
## Important notes
Note that some of these tests (e.g. `spectral/fish`) tend to be very sensitive
to branch predictor effectiveness. This means that changes in the compiler
can easily be masked by "random" fluctuations in the code layout produced by
particular compiler runs. Recent GHC versions provide the `-fproc-alignment`
flag to pad procedures, ensuring slightly better stability across runs. If you
are seeing an unexpected change in performance try adding `-fproc-alignment=64`
the compiler flags of both your baseline and test tree.
## easy.sh
./easy.sh - easy nofib
Usage: ./easy.sh [ -m mode ] /path/to/baseline/ghc /path/to/new/ghc"
GHC paths can point to the root of the GHC repository,
if it's build with Hadrian.
Available options:
-m MODE nofib mode: fast norm slow
This script caches the results using the sha256 of ghc executable.
Remove these files, if you want to rerun the benchmark.
......@@ -13,10 +13,24 @@ whereas it didn't before. So allocations go up a bit.
Imaginary suite
The comprehension
gen n = [ (q:b) | b <- gen (n-1), q <- [1..nq], safe q 1 b]
has, for each iteration of 'b', a new list [1..nq]. This can floated
and hence and shared, or fused. It's quite delicate which of the two
integrate1D is strict in its second argument 'u', but it also passes 'u' to
function 'f'. Hence it now does some reboxing, which pushes up allocation
I found that there were some very bad loss-of-arity cases in PrelShow.
I found that there were some very bad loss-of-arity cases in PrelShow.
In particular, we had:
showl "" = showChar '"' s
......@@ -41,7 +55,7 @@ I found that there were some very bad loss-of-arity cases in PrelShow.
So I've changed PrelShow.showLitChar to use explicit \s. Even then, showl
doesn't work, because GHC can't see that showl xs can be pushed inside the \s.
So I've put an explict \s there too.
So I've put an explict \s there too.
showl "" s = showChar '"' s
showl ('"':xs) s = showString "\\\"" (showl xs s)
......@@ -49,6 +63,14 @@ I found that there were some very bad loss-of-arity cases in PrelShow.
Net result: imaginary/gen_regexps more than halves in allocation!
If we do
a) some inlining before float-out
b) fold/build fusion before float-out
then queens get 40% more allocation. Presumably the fusion
prevents sharing.
......@@ -68,7 +90,7 @@ It's important to inline p_ident.
There's a very delicate CSE in p_expr
p_expr = seQ q_op [p_term1, p_op, p_term2] ## p_term3
(where all the pterm1,2,3 are really just p_term).
(where all the pterm1,2,3 are really just p_term).
This expands into
p_expr s = case p_term1 s of
......@@ -98,7 +120,7 @@ like this:
xs7_s1i8 :: GHC.Prim.Int# -> [GHC.Base.Char]
[Str: DmdType]
xs7_s1i8 = go_r1og ys_aGO
} in
} in
\ (m_XWf :: GHC.Prim.Int#) ->
case GHC.Prim.<=# m_XWf 1 of wild1_aSI {
GHC.Base.False ->
......@@ -109,20 +131,36 @@ like this:
Notice the 'let' which stops the lambda moving out.
In June 2002, GHC 5.04 emitted four successive
NOTE: Simplifier still going after 4 iterations; bailing out.
messages. I suspect that the simplifer is looping somehow.
messages. I suspect that the simplifier is looping somehow.
If you don't inline getChildren, allocation rises by 25%
There's a functions called f_nand and f_d, which generates tons of
code if you inline them too vigorously. And this can happen because
of a massive result discount.
Moreover if f_d gets inlined too much, you get lots of local lvl_xx
things which make some closures have lots of free variables, which pushes
up allocation.
In spectral/expert/Search.ask there's a statically visible CSE. Catching this
In spectral/expert/Search.ask there's a statically visible CSE. Catching this
depends almost entirely on chance, which is a pity.
Performance dominated by (++) and Show.itos'
The performance of fish depends crucially on inlining scale_vec2.
It turns out to be right on the edge of GHC's normal threshold size, so
......@@ -198,24 +236,51 @@ We would do better to inpline showsPrec9 but it looks too big. Before
it was inlined regardless by the instance-decl stuff. So perf drops slightly.
A good benchmark for beating on big-integer arithmetic
There is a delicate interaction of fusion and full laziness in the comprehension
integerbench :: (Integer -> Integer -> a)
-> Integer -> Integer -> Integer
-> Integer -> Integer -> Integer
-> IO ()
integerbench op astart astep alim bstart bstep blim = do
seqlist ([ a `op` b
| a <- [ astart,astart+astep..alim ]
, b <- [ bstart,astart+bstep..blim ]])
return ()
and the analogous one for Int.
Since the inner loop (for b) doesn't depend on a, we could float the
b-list out; but it may fuse first. In GHC 8 (and most previous
version) this fusion did happen at type Integer, but (accidentally) not for
Int because an interving eval got in the way. So the b-enumeration was floated
out, which led to less allocation of Int values.
In knights/KnightHeuristic, we don't find that possibleMoves is strict
(with important knock-on effects) unless we apply rules before floating
out the literal list [A,B,C...].
Similarly, in f_se (F_Cmp ...) in listcompr (but a smaller effect)
* In knights/KnightHeuristic, we don't find that possibleMoves is strict
(with important knock-on effects) unless we apply rules before floating
out the literal list [A,B,C...].
* Similarly, in f_se (F_Cmp ...) in listcompr (but a smaller effect)
* If we don't inline $wmove, we get an allocation increase of 17%
This program shows the cost of the non-eta-expanded lambdas that arise from
a state monad.
a state monad.
check_perim's several calls to point_colour lead to opportunities for CSE
which may be more or less well taken.
Relies heavily on having a specialised version of Complex.magnitude
(:: Complex Double -> Double) available.
......@@ -226,9 +291,9 @@ this is because the pre-let-floating simplification did too little inlining;
in particular, it did not inline windowToViewport
In spectral/multiplier, we have
In spectral/multiplier, we have
xor = lift21 forceBit f
where f :: Bit -> Bit -> Bit
f 0 0 = 0
......@@ -240,28 +305,28 @@ In spectral/multiplier, we have
So allocation goes up. I don't see a way around this.
spectral/hartel/parstof ends up saying
case (unpackCString "x") of { c:cs -> ... }
quite a bit. We should spot these and behave accordingly.
With GHC 4.08, for some reason the arithmetic defaults to Double. The
right thing is to default to Rational, which accounts for the big increase
in runtime after 4.08
The main function is 'transfer'. It has some complicated join points, and
a big issue is the full laziness can float out many small MFEs that then
a big issue is the full laziness can float out many small MFEs that then
make much bigger closures. It's quite delicate: small changes can make
big differences, and I spent far too long gazing at it.
I found that in my experimental proto 4.09 compiler I had
I found that in my experimental proto 4.09 compiler I had
let ds = go xs in
let $j = .... ds ... in
......@@ -279,11 +344,11 @@ Also, making concat into a good producer made a large gain.
My proto 4.09 still allocates more, partly because of more full laziness relative
to 4.08; I don't know why that happens
Extra allocation is happening in 5.02 as well; perhaps for the same reasons. There is
Extra allocation is happening in 5.02 as well; perhaps for the same reasons. There is
at least one instance of floating that prevents fusion; namely the enumerated lists
in 'transfer'.
A key function is vecsub, which looks like this (after w/w)
......@@ -304,7 +369,7 @@ $wvecsub
case ww5 of wild1 { D# y ->
let { a3 = -## x y
} in $wD# a3
} }
} }
} in (# a, a1, a2 #)
Currently it gets guidance: IF_ARGS 6 [2 2 2 2 2 2] 25 4
......@@ -336,24 +401,53 @@ Omitting the flag gives much better inlining for $wvecsub at least.
Sphere also does 60,000 calls to hPutStr, so I/O plays a major role. Currently
this I/O does a *lot* of allocation, much of it since the adddition of thread-safety.
this I/O does a *lot* of allocation, much of it since the addition of thread-safety.
Does a lot of IO.readFile.
Does a lot of IO.readFile. In GHC.IO.Encoding.UTF8 the demand
analyser sees a strict function with type
a_s1gj :: GHC.IO.Buffer.Buffer GHC.Word.Word8
-> GHC.IO.Buffer.Buffer GHC.Types.Char
-> GHC.Prim.State# GHC.Prim.RealWorld
-> (# GHC.Prim.State# GHC.Prim.RealWorld,
GHC.IO.Buffer.Buffer GHC.Word.Word8,
GHC.IO.Buffer.Buffer GHC.Types.Char) #)
Unboxing both Buffer arguments makes a HUGE difference (halves
allocation); but that makes the worker function have 12 arguments. A
good reason for unboxing even if the worker gets a lot of args.
Same issue with GHC.IO.Encoding.UTF8 as treejoin
Real suite
Same issue with GHC.IO.Encoding.UTF8 as treejoin
Uses appendFile repeatedly rather than opening the output file once,
which leads to numerous file opens/closes. Allocations will rise with
the new I/O subsystem in 5.02 because the I/O buffer will be
re-allocated on the heap for each open, whereas previously it would be
allocated on the C heap and therefore not show up in the stats.
Shootout suite
In May 2016, a series of seemingly unrelated commits changed the runtime
performance of this up and down by ~3%. Maybe a performance cliff. Mailinglist
module NofibUtils where
import Data.Char (ord)
import Data.List (foldl')
import System.Environment (getArgs)
-- | A very simple hash function so that we don't have to store and compare
-- huge output files.
hash :: String -> Int
hash = foldl' (\acc c -> ord c + acc*31) 0
-- | Using @salt xs@ on an loop-invariant @xs@ inside a loop prevents the
-- compiler from floating out the input parameter.
salt :: a -> IO a
salt = pure
{-# NOINLINE salt #-}
salt :: [a] -> IO [a]
-- this won't work with real/lift, but I can't think of another way
salt xs = do
s <- length <$> getArgs
-- Invariant: There are less than 'maxBound' parameters passed to the
-- executable, otherwise this isn't really 'pure'
-- anymore.
pure (take (max (maxBound - 1) s) xs)
\ No newline at end of file
echo '\033]0;NOFIB: starting...\007'
# Settings
# "Library" part
show_usage () {
cat <<EOF
./easy.sh - easy nofib
Usage: ./easy.sh [ -m mode ] /path/to/baseline/ghc /path/to/new/ghc"
GHC paths can point to the root of the GHC repository,
if it's build with Hadrian.
Available options:
-m MODE nofib mode: fast norm slow
This script caches the results using the sha256 of ghc executable.
Remove these files, if you want to rerun the benchmark.
hashoffile () {
shasum -a 256 $1 | awk '{ print $1 }'
# getopt
while getopts 'm:' flag; do
case $flag in
case $OPTARG in
echo "Unknown mode: $OPTARG"
exit 1
?) show_usage
shift $((OPTIND - 1))
if [ $# -ne 2 ]; then
echo "Expected two arguments: ghc executables or roots of source repositories"
exit 1
# Set up
# Arguments can point to GHC repository roots
if [ -d $OLD_HC -a -f "$OLD_HC/_build/stage1/bin/ghc" ]; then
if [ -d $NEW_HC -a -f "$NEW_HC/_build/stage1/bin/ghc" ]; then
# Check we have executables
if [ ! -f $NEW_HC -a -x $OLD_HC ]; then
echo "$OLD_HC is not an executable"
exit 1
if [ ! -f $NEW_HC -a -x $NEW_HC ]; then
echo "$NEW_HC is not an executable"
exit 1
# Info before we get going
echo "Running nofib (mode=$mode) with $OLD_HC and $NEW_HC"
echo "Running nofib (mode=$mode) with $OLD_HC and $NEW_HC" | sed 's/./-/g'
sleep 2
# Run nofib
# Run with old ghc
echo '\033]0;NOFIB: old\007'
OLD_HASH=$(hashoffile $OLD_HC)
if [ -f $OLD_OUTPUT ]; then
echo "$OLD_OUTPUT exists; not re-running."
echo '\033]0;NOFIB: old, cleaning...\007'
make clean
echo '\033]0;NOFIB: old, booting...\007'
make boot mode=$mode HC=$OLD_HC
echo '\033]0;NOFIB: old, benchmarking...\007'
make mode=$mode HC=$OLD_HC 2>&1 | tee $OLD_OUTPUT
# Run with new ghc
echo '\033]0;NOFIB: new\007'
NEW_HASH=$(hashoffile $NEW_HC)
if [ -f $NEW_OUTPUT ]; then
echo "$NEW_OUTPUT exists; not re-running."
echo '\033]0;NOFIB: new, cleaning...\007'
make clean
echo '\033]0;NOFIB: new, booting...\007'
make boot mode=$mode HC=$NEW_HC
echo '\033]0;NOFIB: new, benchmarking...\007'
make mode=$mode HC=$NEW_HC 2>&1 | tee $NEW_OUTPUT
# Done
echo '\033]0;NOFIB: done\007'
# Analyse
./nofib-analyse/nofib-analyse $OLD_OUTPUT $NEW_OUTPUT > report.txt
# Show report
less report.txt
This source diff could not be displayed because it is too large. You can view the blob instead.
2010-06-21 John D. Ramsdell <ramsdell@mitre.org>
* agum.cabal (Version): Released as version 2.3.
* agum.cabal (Build-Depends): changes dependency to
base >= 3 && <5, containers
2009-09-17 John D. Ramsdell <ramsdell@mitre.org>
* agum.cabal (Version): Released as version 2.2.
2009-09-14 John D. Ramsdell <ramsdell@.mitre.org>
* src/Algebra/AbelianGroup/IntLinEq.hs: Integer solutions to
linear equation solver was placed in its own module.
2009-09-13 John D. Ramsdell <ramsdell@mitre.org>
* src/Algebra/AbelianGroup/UnificationMatching.hs (unify): Changed
the result to be a substitution since unification always succeeds.
2009-09-05 John D. Ramsdell <ramsdell@mitre.org>
* src/Algebra/AbelianGroup/UnificationMatching.hs: Added
reference to Andrew Kennedy's Ph.D. thesis as it contains a proof
of correctness of the implemented matching algorithm.
* agum.cabal (Version): Released as version 2.1.
2009-08-29 John D. Ramsdell <ramsdell@mitre.org>
* src/Algebra/AbelianGroup/UnificationMatching.hs (Substitution,
apply): Hid the representation of a substitution and supplied a
function for applying a substitution to a term.
* agum.cabal (Version): Released as version 2.0.
TOP = ../../..
include $(TOP)/mk/boilerplate.mk
SRCS = src/Algebra/AbelianGroup/IntLinEq.hs \
src/Algebra/AbelianGroup/UnificationMatching.hs \
STDIN_FILE = eqn.txt
HC_OPTS += -isrc -package base -package containers
include $(TOP)/mk/target.mk
Version 3, 29 June 2007
Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
The GNU General Public License is a free, copyleft license for
software and other kinds of works.
The licenses for most software and other practical works are designed
to take away your freedom to share and change the works. By contrast,
the GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program--to make sure it remains free
software for all its users. We, the Free Software Foundation, use the
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