Time to draw.Draw a 200x200 image fell from 18.4ms (and 1 malloc) to
5.6ms (and 0 mallocs). It's still relatively slow since it assumes
nothing about the src or mask images, but it does remove the malloc.
There are existing faster, more specialized paths for copies, fills
and image glyph masks.
Also added a "compare to a slow but obviously correct implementation"
check to draw_test.go.
R=rsc, r
CC=golang-dev
https://golang.org/cl/1223044
- implemented setWord, use it where setUint64 is wrong
- divLarge: use fast mulWW, divWW; implemented mulWW, divWW
- better assembly code for addMulVVW
R=rsc
CC=golang-dev
https://golang.org/cl/1258042
Previously the compiler would just emit "internal compiler error" when
trying to compute the remainder of floats or complex types.
R=rsc
CC=golang-dev
https://golang.org/cl/1243041
- support for binary prefix 0b (to match fmt.Format)
- renamed nat.new -> nat.setUint64 for consistency
- more tests
R=r
CC=golang-dev
https://golang.org/cl/1233041
Also update range of Phase and Polar due to signed zero.
[Phase(cmplx(-1, +0)) = pi and Phase(cmplx(-1, -0)) = -pi]
R=rsc, r
CC=golang-dev
https://golang.org/cl/1235041
Timings (as for change 1122043) go from 49ms to 48ms ish. It's
mostly lost in the noise, but it probably doesn't hurt.
R=r
CC=golang-dev
https://golang.org/cl/1179041
To draw.Draw a 32x32 image.Alpha 10000 times,
Before: 633ms with 10000 mallocs
After: 49ms with 0 mallocs
These times are just blitting an image.Alpha, and do not include
rasterizing a glyph's vector contours to an image.Alpha.
The "generic" test case in draw_test.go tests this fast path.
R=rsc
CC=golang-dev
https://golang.org/cl/1122043
- removed last argument (n) from all core arithmetic routines;
instead, use the length of the result
- simplified nat.make implementation and chose a better capacity
for new values, removed a TODO in the process
Changing the constant e from 1 (old) to 4 (new) improved
pidigits -s -n 10000 by ~9% (on a 3.06GHz Intel Core 2 Duo):
user 0m3.882s (old)
user 0m3.549s (new)
R=rsc
CC=golang-dev
https://golang.org/cl/1133043
This permits cgo callbacks to work when run in init code.
Otherwise cgocallback switches to the wrong stack address.
R=rsc
CC=golang-dev
https://golang.org/cl/1123043
- no need to make copies in cases of aliases
- removed deprecated internal shift functions
- minor unrelated simplifications
This change improves pidigits -s -n10000 by almost 20%:
user 0m6.156s (old)
user 0m4.999s (new)
(pidigits -s -n20000 goes from ~25s to ~19s)
R=rsc
CC=golang-dev
https://golang.org/cl/1149041
Because maps are mostly a hidden type, they must be
implemented using reflection values and will not be as
efficient as arrays and slices.
R=rsc
CC=golang-dev
https://golang.org/cl/1127041
- renamed Len -> BitLen, simplified implementation
- renamed old Div, Mod, DivMod -> Que, Rem, QuoRem
- implemented Div, Mod, DivMod (Euclidian definition, more
useful in a mathematical context)
- fixed a bug in Exp (-0 was possible)
- added extra tests to check normalized results everywhere
- uniformly set Int.neg flag at the end of computations
- minor cosmetic cleanups
- ran all tests
R=rsc
CC=golang-dev
https://golang.org/cl/1091041
Import _mulv from Inferno again, change R9 to R2.
Not sure what the other differences were for, but
they weren't working.
TBR=kaib
CC=golang-dev
https://golang.org/cl/1079041
built. Note that they are only built if a //export comment
appears, so other targets should only use them if there is
such a comment.
Fixes#723.
R=rsc
CC=golang-dev
https://golang.org/cl/1073041
When trying to regenerate src/pkg/runtime/darwin/386/defs.h
on a 64 bit capable Snow Leopard (OS X 10.6.3) system I
needed to add -f -m32 to godefs, as this OS and hardware
combination defaults to 64 bit compilation.
For safety, make the same change to the 32 bit FreeBSD
instructions in .../freebsd/defs.c. (Tested OK and no
problems introduced.)
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/1052042
- fixed a couple of bugs in the process
(shift right was incorrect for negative numbers)
- added more tests and made some tests more robust
- changed pidigits back to using shifts to multiply
by 2 instead of add
This improves pidigit -s -n 10000 by approx. 5%:
user 0m6.496s (old)
user 0m6.156s (new)
R=rsc
CC=golang-dev
https://golang.org/cl/963044
This results in an improvement of > 35% for the existing Mul benchmark
using the same karatsuba threshold, and an improvement of > 50% with
a slightly higher threshold (32 instead of 30):
big.BenchmarkMul 500 6731846 ns/op (old alg.)
big.BenchmarkMul 500 4351122 ns/op (new alg.)
big.BenchmarkMul 500 3133782 ns/op (new alg., new theshold)
Also:
- tweaked calibrate.go, use same benchmark as for Mul benchmark
R=rsc
CC=golang-dev
https://golang.org/cl/1037041
Plus:
- calibration "test" - include in tests with gotest -calibrate
- basic Mul benchmark
- extra multiplication tests
- various cleanups
This change improves multiplication speed of numbers >= 30 words
in length (current threshold; found empirically with calibrate):
The multiplication benchmark (multiplication of a variety of long numbers)
improves by ~35%, individual multiplies can be significantly faster.
gotest -benchmarks=Mul
big.BenchmarkMul 500 6829290 ns/op (w/ Karatsuba)
big.BenchmarkMul 100 10600760 ns/op
There's no impact on pidigits for -n=10000 or -n=20000
because the operands are are too small.
R=rsc
CC=golang-dev
https://golang.org/cl/1004042
Rather than confuse people by linking to a spec we
don't fully support, let them just use the package docs.
R=r, rsc
CC=golang-dev
https://golang.org/cl/1016041
This matches the old JSON package behavior.
All lowercase names are not as standard as I believed,
and it seems less surprising to need to write
type T struct { Field string "field" }
to get lower case (behavior after this CL) than it does to need
to write
type T struct { Field string "Field" }
to preserve the case (behavior before this CL).
Also test and fix unmarshal into non-nil interface
value or pointer.
Fixes#744.
R=r
CC=golang-dev
https://golang.org/cl/1013041
Adds two more methods, Timeout and Temporary.
Implemented by os.Errno too. The intent is to make
the checks for os.EAGAIN a little less clunky.
It should also let us clean up a bug that Mike Solomon
pointed out: if a network server gets an "out of file descriptors"
error from Accept, the listener should not stop.
It will be able to check this because that error would
have Temporary() == true.
Also clean up some underscore names.
Fixes#442.
R=r
CC=golang-dev, msolo
https://golang.org/cl/957045
There was a bug in makeN that caused lots of unnecessary
allocations. Fixing this exposed a few bugs in other
functions which worked when makeN allocated a new slice, but
failed when it simply resized an existing slice. The result
is a pretty big performance improvement. When running
pidigits, here were the numbers I got on amd64:
Before this change:
pidigits 10000
gcc -O2 pidigits.c -lgmp 2.09u 0.02s 2.11r
gc pidigits 12.68u 0.04s 12.72r
gc_B pidigits 12.71u 0.03s 12.75r
After:
pidigits 10000
gcc -O2 pidigits.c -lgmp 2.09u 0.00s 2.10r
gc pidigits 6.82u 0.00s 6.85r
gc_B pidigits 6.55u 0.01s 6.59r
R=rsc, gri
CC=golang-dev
https://golang.org/cl/953042
Due to page boundary rounding, the header would have
been loaded as part of the text segment already, but this
change placates the "paxctl" tool on so-called hardened
Linux distributions (as if normal distributions weren't already
hard enough to use).
R=r
CC=golang-dev
https://golang.org/cl/954041
SETSID does return an errno - any reason why it has been done this
way in zsyscall_linux_* ? Otherwise it should be the same as darwin.
From SETSID(2) on my Linux box:
ERRORS
On error, -1 is returned, and errno is set.
Fixes#730
R=rsc
CC=golang-dev
https://golang.org/cl/878047
This is the first of probably four separate CLs
for the new implementation of the json package.
The scanner is the core of the new implementation.
The other CLs would be the new decoder,
the new encoder, and support for JSON streams.
R=r
CC=golang-dev
https://golang.org/cl/802051