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Commit Graph

33953 Commits

Author SHA1 Message Date
Josh Bleecher Snyder
77a9cb9b4c runtime: refactor evacuate x/y handling
This change unifies the x and y cases.

It shrinks evacuate's machine code by ~25% and its stack size by ~15%.

It also eliminates a critical branch.
Whether an entry should go to x or y is designed to be unpredictable.
As a result, half of the branch predictions for useX were wrong.
Mispredicting that branch can easily incur an expensive cache miss.
Switching to an xy array allows elimination of that branch,
which in turn reduces cache misses.

Change-Id: Ie9cef53744b96c724c377ac0985b487fc50b49b1
Reviewed-on: https://go-review.googlesource.com/54653
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-14 23:51:14 +00:00
Josh Bleecher Snyder
589fc314af runtime: calculate k only once in mapiternext
Make the calculation of k and v a bit lazier.
None of the following code cares about indirect-vs-direct k,
and it happens on all code paths, so check t.indirectkey earlier.

Simplifies the code and reduces both machine code and stack size.

Change-Id: I5ea4c0772848d7a4b15383baedb9a1f7feb47201
Reviewed-on: https://go-review.googlesource.com/55092
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-14 23:32:56 +00:00
Josh Bleecher Snyder
29e9b89b9a runtime: special case allocation of arrays of size 1
This avoids division and multiplication.
Instrumentation suggests that this is a very common case.

Change-Id: I2d5d5012d4f4df4c4af1f9f85ca9c323c9889c0e
Reviewed-on: https://go-review.googlesource.com/54657
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-14 23:32:03 +00:00
Josh Bleecher Snyder
733567a186 runtime: use integer math for hashmap overLoadFactor
Change-Id: I92cf39a05e738a03d956779d7a1ab1ef8074b2ab
Reviewed-on: https://go-review.googlesource.com/54655
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-14 23:31:22 +00:00
Joe Tsai
694875cbf2 archive/tar: remove writeHeader and writePAXHeaderLegacy
Previous CLs (CL/54970, CL55231, and CL/55237) re-implemented tar.Writer
entirely using specialized methods (writeUSTARHeader, writePAXHeader,
and writeGNUHeader) allowing tar.Writer to entirely side-step the broken
and buggy logic in writeHeader.

Since writeHeader and writePAXHeaderLegacy is now dead-code,
we can delete them.

One minor change is that we call Writer.Flush at the start of WriteHeader.
This used to be performed by writeHeader, but doing so in WriteHeader
ensures each of the specialized methods can benefit from its effect.

Fixes #17665
Fixes #12594

Change-Id: Iff2ef8e7310d40ac5484d2f8852fc5df25201426
Reviewed-on: https://go-review.googlesource.com/55550
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 23:29:25 +00:00
Joe Tsai
ffd9810e59 archive/tar: implement specialized logic for GNU format
Rather than going through writeHeader, which attempts to handle all formats,
implement writeGNUHeader, which only has an understanding of the GNU format.

Currently, the implementation is nearly identical to writeUSTARHeader, except:
* formatNumeric is used instead of formatOctal
* the GNU magic value is used

This is kept as a separate method since it makes more logical sense
when we add support for sparse files, long filenames, and atime/ctime fields,
which do not affect USTAR.

Updates #12594

Change-Id: I76efc0b39dc649efc22646dfc9867a7c165f34a8
Reviewed-on: https://go-review.googlesource.com/55237
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-08-14 21:50:56 +00:00
Martin Möhrmann
d180d18666 strings: use slice instead of list and array in Fields comment
Change-Id: I70b839ff0ae5f015587390a82616ebb1d657d71a
Reviewed-on: https://go-review.googlesource.com/55490
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 21:25:53 +00:00
Martin Möhrmann
248a7c7c42 runtime: replace some uses of newarray with newobject for maps
This avoids the never triggered capacity checks in newarray.

Change-Id: Ib72b204adcb9e3fd3ab963defe0cd40e22d5d492
Reviewed-on: https://go-review.googlesource.com/54731
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-14 21:25:02 +00:00
Martin Möhrmann
7df29b50b2 bytes: speed up Fields and FieldsFunc
Applies the optimizations from golang.org/cl/42810 and golang.org/cl/37959
done to the strings package to the bytes package.

name                      old time/op    new time/op     delta
Fields/ASCII/16              417ns ± 4%      118ns ± 3%    -71.65%  (p=0.000 n=10+10)
Fields/ASCII/256            5.95µs ± 3%     0.88µs ± 0%    -85.23%  (p=0.000 n=10+7)
Fields/ASCII/4096           92.3µs ± 1%     12.8µs ± 2%    -86.13%  (p=0.000 n=10+10)
Fields/ASCII/65536          1.49ms ± 1%     0.25ms ± 1%    -83.14%  (p=0.000 n=10+10)
Fields/ASCII/1048576        25.0ms ± 1%      6.5ms ± 2%    -74.04%  (p=0.000 n=10+10)
Fields/Mixed/16              406ns ± 1%      222ns ± 1%    -45.24%  (p=0.000 n=10+9)
Fields/Mixed/256            5.78µs ± 1%     2.27µs ± 1%    -60.73%  (p=0.000 n=9+10)
Fields/Mixed/4096           97.9µs ± 1%     40.5µs ± 3%    -58.66%  (p=0.000 n=10+10)
Fields/Mixed/65536          1.58ms ± 1%     0.69ms ± 1%    -56.58%  (p=0.000 n=10+10)
Fields/Mixed/1048576        26.6ms ± 1%     12.6ms ± 2%    -52.44%  (p=0.000 n=9+10)
FieldsFunc/ASCII/16          395ns ± 1%      188ns ± 1%    -52.34%  (p=0.000 n=10+10)
FieldsFunc/ASCII/256        5.90µs ± 1%     2.00µs ± 1%    -66.06%  (p=0.000 n=10+10)
FieldsFunc/ASCII/4096       92.5µs ± 1%     33.0µs ± 1%    -64.34%  (p=0.000 n=10+9)
FieldsFunc/ASCII/65536      1.48ms ± 1%     0.54ms ± 1%    -63.38%  (p=0.000 n=10+9)
FieldsFunc/ASCII/1048576    25.1ms ± 1%     10.5ms ± 3%    -58.24%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16          401ns ± 1%      205ns ± 2%    -48.87%  (p=0.000 n=10+10)
FieldsFunc/Mixed/256        5.70µs ± 1%     1.98µs ± 1%    -65.28%  (p=0.000 n=10+10)
FieldsFunc/Mixed/4096       97.5µs ± 1%     35.4µs ± 1%    -63.65%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536      1.57ms ± 1%     0.61ms ± 1%    -61.20%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576    26.5ms ± 1%     11.4ms ± 2%    -56.84%  (p=0.000 n=10+10)

name                      old speed      new speed       delta
Fields/ASCII/16           38.4MB/s ± 4%  134.9MB/s ± 3%   +251.55%  (p=0.000 n=10+10)
Fields/ASCII/256          43.0MB/s ± 3%  290.6MB/s ± 1%   +575.97%  (p=0.000 n=10+8)
Fields/ASCII/4096         44.4MB/s ± 1%  320.0MB/s ± 2%   +620.90%  (p=0.000 n=10+10)
Fields/ASCII/65536        44.0MB/s ± 1%  260.7MB/s ± 1%   +493.15%  (p=0.000 n=10+10)
Fields/ASCII/1048576      42.0MB/s ± 1%  161.6MB/s ± 2%   +285.21%  (p=0.000 n=10+10)
Fields/Mixed/16           39.4MB/s ± 1%   71.7MB/s ± 1%    +82.20%  (p=0.000 n=10+10)
Fields/Mixed/256          44.3MB/s ± 1%  112.8MB/s ± 1%   +154.64%  (p=0.000 n=9+10)
Fields/Mixed/4096         41.9MB/s ± 1%  101.2MB/s ± 3%   +141.92%  (p=0.000 n=10+10)
Fields/Mixed/65536        41.5MB/s ± 1%   95.5MB/s ± 1%   +130.29%  (p=0.000 n=10+10)
Fields/Mixed/1048576      39.4MB/s ± 1%   82.9MB/s ± 2%   +110.28%  (p=0.000 n=9+10)
FieldsFunc/ASCII/16       40.5MB/s ± 1%   84.9MB/s ± 2%   +109.80%  (p=0.000 n=10+10)
FieldsFunc/ASCII/256      43.4MB/s ± 1%  127.9MB/s ± 1%   +194.58%  (p=0.000 n=10+10)
FieldsFunc/ASCII/4096     44.3MB/s ± 1%  124.2MB/s ± 1%   +180.44%  (p=0.000 n=10+9)
FieldsFunc/ASCII/65536    44.2MB/s ± 1%  120.6MB/s ± 1%   +173.06%  (p=0.000 n=10+9)
FieldsFunc/ASCII/1048576  41.8MB/s ± 1%  100.2MB/s ± 3%   +139.53%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16       39.8MB/s ± 1%   77.8MB/s ± 2%    +95.46%  (p=0.000 n=10+10)
FieldsFunc/Mixed/256      44.9MB/s ± 1%  129.4MB/s ± 1%   +187.97%  (p=0.000 n=10+10)
FieldsFunc/Mixed/4096     42.0MB/s ± 1%  115.6MB/s ± 1%   +175.08%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536    41.6MB/s ± 1%  107.3MB/s ± 1%   +157.75%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576  39.6MB/s ± 1%   91.8MB/s ± 2%   +131.72%  (p=0.000 n=10+10)

name                      old alloc/op   new alloc/op    delta
Fields/ASCII/16              80.0B ± 0%      80.0B ± 0%       ~     (all equal)
Fields/ASCII/256              768B ± 0%       768B ± 0%       ~     (all equal)
Fields/ASCII/4096           9.47kB ± 0%     9.47kB ± 0%       ~     (all equal)
Fields/ASCII/65536           147kB ± 0%      147kB ± 0%       ~     (all equal)
Fields/ASCII/1048576        2.27MB ± 0%     2.27MB ± 0%       ~     (all equal)
Fields/Mixed/16              96.0B ± 0%      96.0B ± 0%       ~     (all equal)
Fields/Mixed/256              768B ± 0%       768B ± 0%       ~     (all equal)
Fields/Mixed/4096           9.47kB ± 0%    24.83kB ± 0%   +162.16%  (p=0.000 n=10+10)
Fields/Mixed/65536           147kB ± 0%      497kB ± 0%   +237.24%  (p=0.000 n=10+10)
Fields/Mixed/1048576        2.26MB ± 0%     9.61MB ± 0%   +324.89%  (p=0.000 n=10+10)
FieldsFunc/ASCII/16          80.0B ± 0%      80.0B ± 0%       ~     (all equal)
FieldsFunc/ASCII/256          768B ± 0%       768B ± 0%       ~     (all equal)
FieldsFunc/ASCII/4096       9.47kB ± 0%    24.83kB ± 0%   +162.16%  (p=0.000 n=10+10)
FieldsFunc/ASCII/65536       147kB ± 0%      497kB ± 0%   +237.24%  (p=0.000 n=10+10)
FieldsFunc/ASCII/1048576    2.27MB ± 0%     9.61MB ± 0%   +323.72%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16          96.0B ± 0%      96.0B ± 0%       ~     (all equal)
FieldsFunc/Mixed/256          768B ± 0%       768B ± 0%       ~     (all equal)
FieldsFunc/Mixed/4096       9.47kB ± 0%    24.83kB ± 0%   +162.16%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536       147kB ± 0%      497kB ± 0%   +237.24%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576    2.26MB ± 0%     9.61MB ± 0%   +324.89%  (p=0.000 n=10+10)

name                      old allocs/op  new allocs/op   delta
Fields/ASCII/16               1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/256              1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/4096             1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/65536            1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/ASCII/1048576          1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/Mixed/16               1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/Mixed/256              1.00 ± 0%       1.00 ± 0%       ~     (all equal)
Fields/Mixed/4096             1.00 ± 0%       5.00 ± 0%   +400.00%  (p=0.000 n=10+10)
Fields/Mixed/65536            1.00 ± 0%      12.00 ± 0%  +1100.00%  (p=0.000 n=10+10)
Fields/Mixed/1048576          1.00 ± 0%      24.00 ± 0%  +2300.00%  (p=0.000 n=10+10)
FieldsFunc/ASCII/16           1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/ASCII/256          1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/ASCII/4096         1.00 ± 0%       5.00 ± 0%   +400.00%  (p=0.000 n=10+10)
FieldsFunc/ASCII/65536        1.00 ± 0%      12.00 ± 0%  +1100.00%  (p=0.000 n=10+10)
FieldsFunc/ASCII/1048576      1.00 ± 0%      24.00 ± 0%  +2300.00%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16           1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/Mixed/256          1.00 ± 0%       1.00 ± 0%       ~     (all equal)
FieldsFunc/Mixed/4096         1.00 ± 0%       5.00 ± 0%   +400.00%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536        1.00 ± 0%      12.00 ± 0%  +1100.00%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576      1.00 ± 0%      24.00 ± 0%  +2300.00%  (p=0.000 n=10+10)

Change-Id: If1926782decc2f60d3b4b8c41c2ce7d8bdedfd8f
Reviewed-on: https://go-review.googlesource.com/55131
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-14 21:08:51 +00:00
Martin Möhrmann
dd6880d69b strconv: unify error creation in ParseUint with ParseInt
Remove goto and use helper functions in ParseUint to create errors.

Change-Id: I1c4677ae1b9980db79065a9f8ca1f2c470249505
Reviewed-on: https://go-review.googlesource.com/55135
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-14 21:02:21 +00:00
Martin Möhrmann
566f390cfa strconv: adjust test output and names for parseUint and parseInt
Instead of printing Atoi as function name for test failures
print the actual function name and arguments tested.

Add a base field to the parseUint64BaseTests for consistency with
the parseInt64BaseTests tests.

Change-Id: Ib9891bdb87b62672b4216625212acfe6474c70fc
Reviewed-on: https://go-review.googlesource.com/55136
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-14 20:51:59 +00:00
Keith Randall
2c990f4596 runtime: add a use of runtime.KeepAlive's argument
This makes sure that its argument is marked live on entry.
We need its arg to be live so defers of KeepAlive get
scanned correctly by the GC.

Fixes #21402

Change-Id: I906813e433d0e9726ca46483723303338da5b4d7
Reviewed-on: https://go-review.googlesource.com/55150
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-14 20:11:21 +00:00
Dmitry Vyukov
1f631a2f9a cmd/go: parallelize fmt
Currently go fmt formats all files sequentially.
That's a shame. Parallelize it over files.

Reduces time of go fmt ./... in std lib
from ~6.1s to ~0.9s.

Reduces time of go fmt github.com/google/syzkaller/...
from ~5.2s to ~1.8s.

Change-Id: I3d27fc25326106b2a4781e13506a25c12d5bcdc5
Reviewed-on: https://go-review.googlesource.com/45491
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-14 19:03:12 +00:00
Ilya Tocar
8b2f84393b encoding/base32: improve performance in common case
Unroll loop to improve perfromance back to 1.8 level.
name              old time/op    new time/op    delta
EncodeToString-6    63.0µs ± 3%    51.7µs ± 2%  -17.94%  (p=0.000 n=10+10)

name              old speed      new speed      delta
EncodeToString-6   130MB/s ± 3%   159MB/s ± 2%  +21.83%  (p=0.000 n=10+10)

Vs 1.8:
EncodeToString-6    54.9µs ± 2%    51.7µs ± 2%   -5.95%  (p=0.000 n=10+10)

name              old speed      new speed      delta
EncodeToString-6   149MB/s ± 2%   159MB/s ± 2%   +6.32%  (p=0.000 n=10+10)

Fixes #21262

Change-Id: I41bf7e1f61041781386d16d573bffe1a7173c0c3
Reviewed-on: https://go-review.googlesource.com/52510
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-14 18:51:14 +00:00
Hiroshi Ioka
1f8433c66a cmd/link: don't link the same dylib multiple times
Also, unexport Machoadddynlib

n=`go test -c crypto/x509 && otool -l x509.test | grep libSystem | wc -l`

Before this CL, n = 3.
After this CL, n = 1.

on my environment.

Change-Id: Ic7b8157435cc85086404860dc6c84eb0aecc5d19
Reviewed-on: https://go-review.googlesource.com/44771
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Avelino <t@avelino.xxx>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 18:48:28 +00:00
Hiroshi Ioka
bac1cc0d16 debug/macho: add relocation types
Fixes #21435

Change-Id: I5f8d93a45b84a871ceea881ecb1a38a37e96006c
Reviewed-on: https://go-review.googlesource.com/55263
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 18:45:40 +00:00
Hiroshi Ioka
b7c600d6ba cmd/go, cmd/link: enable buildmode=pie on darwin/amd64
Change some configurations to enable the feature. Also add the test.
This CL doesn't include internal linking support which is tentatively
disabled due to #18968. We could do that another day.

Fixes #21220

Change-Id: I601d2d78446d36332acc70be0d5b9461ac635208
Reviewed-on: https://go-review.googlesource.com/54790
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 18:45:21 +00:00
Justin Nuß
9fbc06e6aa encoding/csv: preserve \r\n in quoted fields
The parser mistakenly assumed it could always fold \r\n into \n, which
is not true since a \r\n inside a quoted fields has no special meaning
and should be kept as is.

Fix this by not folding \r\n to \n inside quotes fields.

Fixes #21201

Change-Id: Ifebc302e49cf63e0a027ee90f088dbc050a2b7a6
Reviewed-on: https://go-review.googlesource.com/52810
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 18:42:20 +00:00
Daniel Martí
f9cf8e5ab1 net/http: various small cleanups
* Remove an unnecessary type conversion
* Make golint happier about consistent receiver names
* Make golint happier about a foo_bar var name

Change-Id: I5223808109f6f8b69ed4be76de82faf2478c6a2e
Reviewed-on: https://go-review.googlesource.com/54530
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tom Bergan <tombergan@google.com>
2017-08-14 16:37:27 +00:00
Alberto Donizetti
cc4aac2b9b cmd/compile/internal/syntax: fix 'delimiters' spelling
Change-Id: Iffb52a0bdc479642eda3b5a12ba5da6590d0f0ec
Reviewed-on: https://go-review.googlesource.com/55330
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-08-14 14:13:22 +00:00
griesemer
5abc8c897c spec: better comment in example for type definition
The old comment for the example

	type PtrMutex *Mutex

talked about the method set of the base type of PtrMutex.
It's more direct and clearer to talk about the underlying
type of PtrMutex for this specific example.
Also removed link inside pre-formatted region of text.

Fixes #20900.

Change-Id: Ie37340e53670e34ebe13e780ba8ccb1bba67795c
Reviewed-on: https://go-review.googlesource.com/55070
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-14 13:35:43 +00:00
Martin Möhrmann
629b5e7561 fmt: add ascii fast path for decoding verbs
name                    old time/op  new time/op  delta
SprintfSlowParsingPath   108ns ± 4%   103ns ± 4%  -4.53%  (p=0.000 n=18+18)

Change-Id: I174463f303d1857e8d5b8a6283c025b3546e7b39
Reviewed-on: https://go-review.googlesource.com/44450
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
2017-08-14 12:25:45 +00:00
Carlos Eduardo Seo
6661cf6dfd runtime, internal/cpu: CPU capabilities detection for ppc64x
This change replaces the current runtime capabilities check for ppc64x with the
new internal/cpu package. It also adds support for the new POWER9 ISA and
capabilities.

Updates #15403

Change-Id: I5b64a79e782f8da3603e5529600434f602986292
Reviewed-on: https://go-review.googlesource.com/53830
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-08-14 12:16:42 +00:00
Joe Tsai
01385b1bb6 archive/tar: adjust bytediff to print full context
Since test files don't exceed 10KiB, print the full context of the diff,
including bytes that are equal.
Also, fix the labels for got and want; they were backwards before.

Change-Id: Ibac022e5f988d26812c3f75b643cae8b95603fc9
Reviewed-on: https://go-review.googlesource.com/55151
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2017-08-14 06:27:44 +00:00
Joe Tsai
7ae9561610 archive/tar: implement specialized logic for PAX format
Rather than going through writeHeader, which attempts to handle all formats,
implement writePAXHeader, which only has an understanding of the PAX format.

In PAX, the USTAR header is filled out in a best-effort manner.
Thus, we change logic of formatString and formatOctal to try their best to
output something (possibly truncated) in the event of an error.

The new implementation of PAX headers causes several tests to fail.
An investigation into the new output reveals that the new behavior is correct,
while the tests had actually locked in incorrect behavior before.

A dump of the differences is listed below (-before, +after):

<< writer-big.tar >>

This change is due to fact that we changed the Header.Devminor to force the
tar.Writer to choose the GNU format over the PAX one.
The ability to control the output is an open issue (see #18710).
- 00000150  00 30 30 30 30 30 30 30  00 00 00 00 00 00 00 00  |.0000000........|
+ 00000150  00 ff ff ff ff ff ff ff  ff 00 00 00 00 00 00 00  |................|

<< writer-big-long.tar>>

The previous logic generated the GNU magic values for a PAX file.
The new logic correctly uses the USTAR magic values.
- 00000100  00 75 73 74 61 72 20 20  00 00 00 00 00 00 00 00  |.ustar  ........|
- 00000500  00 75 73 74 61 72 20 20  00 67 75 69 6c 6c 61 75  |.ustar  .guillau|
+ 00000100  00 75 73 74 61 72 00 30  30 00 00 00 00 00 00 00  |.ustar.00.......|
+ 00000500  00 75 73 74 61 72 00 30  30 67 75 69 6c 6c 61 75  |.ustar.00guillau|

The previous logic tried to use the specified timestmap in the PAX headers file,
but this is problematic as this timestamp can overflow, defeating the point
of using PAX, which is intended to extend tar.
The new logic uses the zero timestamp similar to what GNU and BSD tar do.
- 00000080  30 30 30 30 32 33 32 00  31 32 33 33 32 37 37 30  |0000232.12332770|
+ 00000080  30 30 30 30 32 35 36 00  30 30 30 30 30 30 30 30  |0000256.00000000|

The previous logic populated the devminor and devmajor fields.
The new logic leaves them zeroed just like what GNU and BSD tar do.
- 00000140  00 00 00 00 00 00 00 00  00 30 30 30 30 30 30 30  |.........0000000|
- 00000150  00 30 30 30 30 30 30 30  00 00 00 00 00 00 00 00  |.0000000........|
+ 00000140  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+ 00000150  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|

The previous logic uses PAX headers, but fails to add a record for the size.
The new logic does properly add a record for the size.
- 00000290  31 36 67 69 67 2e 74 78  74 0a 00 00 00 00 00 00  |16gig.txt.......|
- 000002a0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+ 00000290  31 36 67 69 67 2e 74 78  74 0a 32 30 20 73 69 7a  |16gig.txt.20 siz|
+ 000002a0  65 3d 31 37 31 37 39 38  36 39 31 38 34 0a 00 00  |e=17179869184...|

The previous logic encoded the size as a base-256 field,
which is only valid in GNU, but the previous PAX headers implies this should
be a PAX file. This result in a strange hybrid that is neither GNU nor PAX.
The new logic uses PAX headers to store the size.
- 00000470  37 35 30 00 30 30 30 31  37 35 30 00 80 00 00 00  |750.0001750.....|
- 00000480  00 00 00 04 00 00 00 00  31 32 33 33 32 37 37 30  |........12332770|
+ 00000470  37 35 30 00 30 30 30 31  37 35 30 00 30 30 30 30  |750.0001750.0000|
+ 00000480  30 30 30 30 30 30 30 00  31 32 33 33 32 37 37 30  |0000000.12332770|

<< ustar.issue12594.tar >>

The previous logic used the specified timestamp for the PAX headers file.
The new logic just uses the zero timestmap.
- 00000080  30 30 30 30 32 33 31 00  31 32 31 30 34 34 30 32  |0000231.12104402|
+ 00000080  30 30 30 30 32 33 31 00  30 30 30 30 30 30 30 30  |0000231.00000000|

The previous logic populated the devminor and devmajor fields.
The new logic leaves them zeroed just like what GNU and BSD tar do.
- 00000140  00 00 00 00 00 00 00 00  00 30 30 30 30 30 30 30  |.........0000000|
- 00000150  00 30 30 30 30 30 30 30  00 00 00 00 00 00 00 00  |.0000000........|
+ 00000140  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
+ 00000150  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|

Change-Id: I33419eb1124951968e9d5a10d50027e03133c811
Reviewed-on: https://go-review.googlesource.com/55231
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 06:26:35 +00:00
Hiroshi Ioka
b88e532a9e cmd/cgo: use first error position instead of last one
Just like https://golang.org/cl/34783

Given cgo.go:
     1	package main
     2
     3	/*
     4	long double x = 0;
     5	*/
     6	import "C"
     7
     8	func main() {
     9		_ = C.x
    10		_ = C.x
    11	}

Before:
    ./cgo.go:10:6: unexpected: 16-byte float type - long double

After:
    ./cgo.go:9:6: unexpected: 16-byte float type - long double

The above test case is not portable. So it is tested on only amd64.

Change-Id: If0b84cf73d381a22e2ada71c8e9a6e6ec77ffd2e
Reviewed-on: https://go-review.googlesource.com/54950
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-14 05:29:11 +00:00
Hiroshi Ioka
5b43bbe63b cmd/link: prefer to use constants in macho.go
We might want to replace some linker's feature by debug/macho in future.
This CL gathers information of required constants.

Change-Id: Iea14abdb32709a4f5404a17874f9c925d29ba999
Reviewed-on: https://go-review.googlesource.com/55252
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 05:28:38 +00:00
Hiroshi Ioka
6424c40c22 cmd/link: don't emit default entry symbol in some situations
Also, fix comment.

Change-Id: Ieb7ba21f34730dc51ab45a652d225e4145d4b861
Reviewed-on: https://go-review.googlesource.com/54870
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-14 05:28:22 +00:00
Hiroshi Ioka
d03b89bd41 debug/macho: add some file flags
Fixes #21414

Change-Id: Idff6e269ae32b33253067c9f32cac25256eb7f1c
Reviewed-on: https://go-review.googlesource.com/55251
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 05:27:53 +00:00
Agniva De Sarker
98276d6abe encoding/hex: improve tests
The tests for error scenarios were done by manually checking
error strings. Improved them by checking the actual error type
instead of just the string.

Printing the actual error in case of failure instead of a
generic string.

Also added a new scenario with both an invalid byte and an
invalid length string to verify that the length is checked first
before doing any computation.

Change-Id: Ic2a19a6d6058912632d597590186ee2d8348cb45
Reviewed-on: https://go-review.googlesource.com/55256
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 04:45:52 +00:00
Justin Nuß
5d14ac74f6 encoding/csv: report line start line in errors
Errors returned by Reader contain the line where the Reader originally
encountered the error. This can be suboptimal since that line does not
always correspond with the line the current record/field started at.

This can easily happen with LazyQuotes as seen in #19019, but also
happens for example when a quoted fields has no closing quote and
the parser hits EOF before it finds another quote.

When this happens finding the erroneous field can be somewhat
complicated and time consuming, and in most cases it would be better to
report the line where the record started.

This change updates Reader to keep track of the line on which a record
begins and uses it for errors instead of the current line, making it
easier to find errors.

Although a user-visible change, this should have no impact on existing
code, since most users don't explicitly work with the line in the error
and probably already expect the new behaviour.

Updates #19019

Change-Id: Ic9bc70fad2651c69435d614d537e7a9266819b05
Reviewed-on: https://go-review.googlesource.com/52830
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 04:45:38 +00:00
Hiroshi Ioka
342d25fc05 cmd/link: remove redundant switch stmt
Change-Id: I5c4f8dc1e174b3438ef4fb509fac78d6e1b292c9
Reviewed-on: https://go-review.googlesource.com/54791
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Avelino <t@avelino.xxx>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 04:44:35 +00:00
Rob Pike
b1fab09901 cmd/vet: fix a couple of minor word choices in README
No semantic change, just clarifying a bit by choosing better words
in a couple of places.

Change-Id: I4496062ee7909baf83d4d22d25e13ef93b358b4b
Reviewed-on: https://go-review.googlesource.com/55255
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-14 04:15:59 +00:00
Tobias Klauser
67c360594f syscall: add utimensat and use it for UtimesNano on BSD and Solaris
All the BSDs and Solaris support the utimensat syscall, but Darwin
doesn't. Account for that by adding the //sys lines not to
syscall_bsd.go but the individual OS's syscall_*.go files and implement
utimensat on Darwin as just returning ENOSYS, such that UtimesNano will
fall back to use utimes as it currently does unconditionally.

This also adds the previously missing utimensat syscall number for
FreeBSD and Dragonfly.

Fixes #16480

Change-Id: I367454c6168eb1f7150b988fa16cf02abff42f34
Reviewed-on: https://go-review.googlesource.com/55130
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2017-08-14 04:14:41 +00:00
Kevin Burke
6203a79b52 time: remove unused parameter
lookupName is only called in one location, and one of the return
values is unused, so let's remove it.

Change-Id: I35e22c7ec611e8eb349deb4f0561e212f7d9de0b
Reviewed-on: https://go-review.googlesource.com/55232
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
2017-08-14 02:22:20 +00:00
Austin Clements
c8e9fd5db0 Revert "Revert "cmd/compile: discard duplicate inline method bodies""
This reverts commit f612cd704a.

Reason for revert: We thought the original change had broken the
linux/amd64 and linux/386 builders, but it turned out to be a problem
with the build infrastructure, not the change.

Change-Id: Ic3318a63464fcba8d845ac04494115a7ba620364
Reviewed-on: https://go-review.googlesource.com/55050
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-08-14 01:38:08 +00:00
Josh Bleecher Snyder
e0789d734d runtime: remove indentation in mapiternext
Invert the condition and continue, to remove indentation.

Change-Id: Id62a5d9abc9a4df1193bcf15f95f70f2c2e2abac
Reviewed-on: https://go-review.googlesource.com/55091
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-08-14 00:52:16 +00:00
Josh Bleecher Snyder
f5804ce4f3 runtime: simplify hashmap tooManyOverflowBuckets
This generates better code.

Masking B in the return statement should be unnecessary,
but the compiler is understandably not yet clever enough to see that.

Someday, it'd also be nice for the compiler to generate
a CMOV for the saturation if statement.

Change-Id: Ie1c157b21f5212610da1f3c7823a93816b3b61b9
Reviewed-on: https://go-review.googlesource.com/54656
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-08-14 00:51:48 +00:00
Josh Bleecher Snyder
aca92f352d runtime: CSE some function arguments in evacuate
Shrinks evacuate's machine code a little.

Change-Id: I08874c92abdc7e621bc0737e22f2a6be31542cab
Reviewed-on: https://go-review.googlesource.com/54652
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-08-14 00:51:14 +00:00
Josh Bleecher Snyder
a6136ded32 runtime: remove indentation in evacuate
Combine conditions into a single if statement.
This is more readable.

It should generate identical machine code, but it doesn't.
The new code is shorter.

Change-Id: I9bf52f8f288b0df97a2b9b4e4183f6ca74175e8a
Reviewed-on: https://go-review.googlesource.com/54651
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-08-14 00:51:02 +00:00
Josh Bleecher Snyder
38044eca7c runtime: make map deletion benchmarks faster to run
This reduces the wall time to run these benchmarks by about 30%.

Change-Id: I494a93c93e5acb1514510d85f65796f62e1629a5
Reviewed-on: https://go-review.googlesource.com/54650
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-08-14 00:50:52 +00:00
Austin Clements
9065c3bf34 runtime: support DT_GNU_HASH in VDSO
Currently we only support finding symbols in the VDSO using the old
DT_HASH. These days everything uses DT_GNU_HASH instead. To keep up
with the times and future-proof against DT_HASH disappearing from the
VDSO in the future, this commit adds support for DT_GNU_HASH and
prefers it over DT_HASH.

Tested by making sure it found a DT_GNU_HASH section and all of the
expected symbols in it, and then disabling the DT_GNU_HASH path and
making sure the old DT_HASH path still found all of the symbols.

Fixes #19649.

Change-Id: I508c8b35a019330d2c32f04f3833b69cb2686f13
Reviewed-on: https://go-review.googlesource.com/45511
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-13 22:08:55 +00:00
Audrey Lim
816deacc70 archive/zip: fix Writer to validate file
The ZIP format uses uint16 to contain the length of the file name and
the length of the Extra section. This change verifies that the length
of these fields fit in an uint16 prior to writing the ZIP file. If not,
an error is returned.

Fixes #17402

Change-Id: Ief9a864d2fe16b89ddb9917838283b801a2c58a4
Reviewed-on: https://go-review.googlesource.com/50250
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-13 17:33:10 +00:00
Martin Möhrmann
09ed0f6805 strconv: avoid truncation of output in parse int tests
If needed cast the test table values to a higher bit size
integer type instead of casting the result values of the
tested function to a lower bit size integer type.

Change-Id: Iaa79742b2b1d90c7c7eac324f54032ebea0b1b41
Reviewed-on: https://go-review.googlesource.com/55137
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-13 10:08:42 +00:00
Martin Möhrmann
fee7f2ab16 strings: speed up FieldsFunc
Increases performance of FieldsFunc by recording the start and end
of the fields in an array. The first 32 fields are saved in a pre-allocated
array on the stack. This avoids the old behavior of iterating over the
input string two times but uses more allocations when more than 32 fields
are encountered.

Additionally code for handling non-ASCII containing strings from Fields is
removed and replaced by a call to the new faster FieldsFunc function.

Overall this still leads to a slowdown for Fields on non-ASCII strings
while speeding up Fields in general.

name                      old time/op    new time/op     delta
Fields/ASCII/16              116ns ± 5%      115ns ± 5%       ~     (p=0.480 n=10+10)
Fields/ASCII/256             765ns ± 1%      761ns ± 2%       ~     (p=0.171 n=10+10)
Fields/ASCII/4096           12.5µs ± 1%     12.7µs ± 1%     +1.82%  (p=0.000 n=10+10)
Fields/ASCII/65536           226µs ± 1%      226µs ± 2%       ~     (p=0.739 n=10+10)
Fields/ASCII/1048576        5.12ms ± 1%     5.12ms ± 1%       ~     (p=0.696 n=8+10)
Fields/Mixed/16              172ns ± 1%      233ns ± 1%    +35.90%  (p=0.000 n=9+10)
Fields/Mixed/256            1.18µs ± 2%     2.45µs ± 1%   +107.47%  (p=0.000 n=10+10)
Fields/Mixed/4096           20.3µs ± 1%     43.1µs ± 2%   +112.41%  (p=0.000 n=10+10)
Fields/Mixed/65536           364µs ± 1%      704µs ± 1%    +93.56%  (p=0.000 n=9+10)
Fields/Mixed/1048576        7.07ms ± 2%    13.34ms ± 4%    +88.83%  (p=0.000 n=10+10)
FieldsFunc/ASCII/16          274ns ± 1%      188ns ± 3%    -31.44%  (p=0.000 n=10+10)
FieldsFunc/ASCII/256        3.69µs ± 1%     2.06µs ± 2%    -44.26%  (p=0.000 n=10+10)
FieldsFunc/ASCII/4096       59.9µs ± 1%     35.3µs ± 2%    -41.10%  (p=0.000 n=10+10)
FieldsFunc/ASCII/65536       958µs ± 1%      567µs ± 1%    -40.82%  (p=0.000 n=10+9)
FieldsFunc/ASCII/1048576    16.3ms ± 2%     11.0ms ± 3%    -32.52%  (p=0.000 n=10+10)
FieldsFunc/Mixed/16          309ns ± 1%      213ns ± 0%    -30.98%  (p=0.000 n=10+6)
FieldsFunc/Mixed/256        3.83µs ± 1%     2.14µs ± 1%    -44.01%  (p=0.000 n=10+10)
FieldsFunc/Mixed/4096       66.2µs ± 2%     37.8µs ± 1%    -42.85%  (p=0.000 n=10+10)
FieldsFunc/Mixed/65536      1.09ms ± 1%     0.63ms ± 1%    -42.73%  (p=0.000 n=10+10)
FieldsFunc/Mixed/1048576    18.6ms ± 3%     12.0ms ± 2%    -35.50%  (p=0.000 n=10+10)

Fixes #17856
Fixes #19789

Change-Id: I9f5a560e534566fd81963651f342c8f44cfb0469
Reviewed-on: https://go-review.googlesource.com/42810
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-13 09:58:01 +00:00
Martin Möhrmann
fc6b74ce39 strconv: fix ParseUint return value on range overflow
If the value corresponding to the input string cannot be
represented by an unsigned integer of the given size,
err.Err = ErrRange and the returned value is the maximum
magnitude unsigned integer of the appropriate bitSize.
This is consistent with ParseInt's behavior and the documentation.

Expand tests to test 32 bit test value tables with bitsize 32 set.
These tests fail without the fix in this CL.

Fixes #21278

Change-Id: I8aab39279ec3e31905fcbf582a916cbf6d9b95da
Reviewed-on: https://go-review.googlesource.com/55134
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-13 09:11:32 +00:00
Joe Tsai
1d81251599 archive/tar: simplify toASCII and parseString
Use a simple []byte instead of bytes.Buffer to create a string.
Use bytes.IndexByte instead of our own for loop.

Change-Id: Ic4a1161d79017fd3af086a05c53d5f20a5f09326
Reviewed-on: https://go-review.googlesource.com/54752
Reviewed-by: Avelino <t@avelino.xxx>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-13 02:32:28 +00:00
Agniva De Sarker
23cd87eb0a archive/tar: optimize formatPAXRecord() call
By replacing fmt.Sprintf with a simple string concat, we see
pretty good improvements across the board on time and memory.

name             old time/op    new time/op    delta
FormatPAXRecord     683ns ± 2%     210ns ± 5%  -69.22%  (p=0.000 n=10+10)

name             old alloc/op   new alloc/op   delta
FormatPAXRecord      112B ± 0%       32B ± 0%  -71.43%  (p=0.000 n=10+10)

name             old allocs/op  new allocs/op  delta
FormatPAXRecord      8.00 ± 0%      2.00 ± 0%  -75.00%  (p=0.000 n=10+10)

Ran with - -cpu=1 -count=10 on an AMD64 i5-5200U CPU @ 2.20GHz

Using the following benchmark:
func BenchmarkFormatPAXRecord(b *testing.B) {
  for n := 0; n < b.N; n++ {
    formatPAXRecord("foo", "bar")
  }
}

Change-Id: I828ddbafad2e5d937f0cf5f777b512638344acfc
Reviewed-on: https://go-review.googlesource.com/55210
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-12 04:52:27 +00:00
Joe Tsai
0d1a8f6e12 archive/tar: implement specialized logic for USTAR format
Rather than going through the complicated logic of writeHeader,
implement a writeUSTARHeader that only knows about the USTAR format.
This makes the logic much easier to reason about since you only
need to be concerned about USTAR and not all the subtle
differences between USTAR, PAX, and GNU.

We seperate out the logic in writeUSTARHeader into templateV7Plus
and writeRawHeader since the planned implementations of
writePAXHeader and writeGNUHeader will use them.

Change-Id: Ie75a54ac998420ece82686159ae6fa39f8b128e9
Reviewed-on: https://go-review.googlesource.com/54970
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-12 01:48:06 +00:00
Mark Wolfe
812124a567 encoding/binary: add example for Read multi
Change-Id: I27ff99aa7abb070f6ae79c8f964aa9bd6a83b89d
Reviewed-on: https://go-review.googlesource.com/53730
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-12 01:17:13 +00:00