This updates the bundled http2 package from git rev
5602c733f70afc6dcec6766be0d5034d4c4f14de of the x/net repo for:

  http2: Use NO_ERROR instead of CANCEL when responding before the request is finished
  https://golang.org/cl/40630

  http2: enforce write deadline per stream
  https://golang.org/cl/34727

Updates golang/go#19948
Fixes golang/go#18437

Change-Id: I14500476e91551fa8f27a1aeb8ae3cac9600b74c
Reviewed-on: https://go-review.googlesource.com/41753Reviewed-by: Kale Blankenship <kale@lemnisys.com>
Reviewed-by: Tom Bergan <tombergan@google.com>
Run-TryBot: Kale Blankenship <kale@lemnisys.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Updates golang_org/x/net/route to rev da118f7 for:
- route: don't fail test when at least one version of INET protocols is available

Updates #19298.
Updates #19967.

Change-Id: I46948f1bd4ac6e6afd424623233f90e2b6b954c6
Reviewed-on: https://go-review.googlesource.com/41652
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Updates golang_org/x/net/lif to rev a25ba90 for:
- lif: don't fail test when at least one version of INET protocols is available

Updates #19967.

Change-Id: I4b946a4c6eee7938193688ecbfc4a9d69d88c94e
Reviewed-on: https://go-review.googlesource.com/41651
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I34547b057605bb9e1e2227c41867589348560244
Reviewed-on: https://go-review.googlesource.com/41513
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Cleanup CL https://golang.org/cl/41691 broke the plan9 build by removing
a use of a package but not removing the package import.

Trybots don't check that. I filed #20119 for that.

Change-Id: Ia030e6924665dfb871ca964455b899d51b0200c2
Reviewed-on: https://go-review.googlesource.com/41752Reviewed-by: David du Colombier <0intro@gmail.com>

In an effort to at least understand the complete set of things not
working on Alpine Linux, I've been trying to get the build passing
again, even with tests disabled.

The race detector is broken on Alpine. That is #14481 (and #9918).
So disable those tests for now.

Also, internal linking with PIE doesn't work on Alpine yet.
That is #18243. So disable that test for now.

With this CL, all.bash almost passes. There's some cgo test failing
still, but there's no bug yet, so that can be a separate CL.

Change-Id: I3ffbb0e787ed54cb82f298b6bd5bf3ccfbc82622
Reviewed-on: https://go-review.googlesource.com/41678
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Version 4 generated with toolchain at commit 51012314.
Version 5 generated with toolchain at commit a6b16e00.

Change-Id: If11ec8b3357f0f71776c15665e4d5228b3842ff7
Reviewed-on: https://go-review.googlesource.com/41710
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Use -64 instead of 0 as the magic "new file"
line delta, since it is much less common.

Use a new path encoding that breaks up paths
into /-separated components, allowing
reuse of the component strings, and making
many re-used paths a single byte to encode.

Bump the export version to 5.

Fixes #20080

name        old export-bytes  new export-bytes  delta
Template          19.1k ± 0%        17.4k ± 0%  -8.74%  (p=0.008 n=5+5)
Unicode           4.47k ± 0%        4.42k ± 0%  -0.96%  (p=0.008 n=5+5)
GoTypes           29.9k ± 0%        27.6k ± 0%  -7.41%  (p=0.008 n=5+5)
Compiler          71.4k ± 0%        65.4k ± 0%  -8.45%  (p=0.008 n=5+5)
SSA               67.8k ± 0%        65.6k ± 0%  -3.38%  (p=0.008 n=5+5)
Flate             4.99k ± 0%        4.79k ± 0%  -3.91%  (p=0.008 n=5+5)
GoParser          8.77k ± 0%        7.97k ± 0%  -9.14%  (p=0.008 n=5+5)
Reflect           6.27k ± 0%        6.13k ± 0%  -2.22%  (p=0.008 n=5+5)
Tar               9.46k ± 0%        8.82k ± 0%  -6.69%  (p=0.008 n=5+5)
XML               16.0k ± 0%        14.9k ± 0%  -6.69%  (p=0.008 n=5+5)
[Geo mean]        14.8k             14.0k       -5.80%

Change-Id: Iea0c8c62e61dbab3cfd14ee121e34845c85f00d2
Reviewed-on: https://go-review.googlesource.com/41619
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

isifacemethod accessed thisT without checking if it was initialized,
opening the possibility for a bug during type checking. Give better
name, move it to package types, and provide accessor instead.

Change-Id: I29ffc408252a4ba4ef1de218fa154397786c9be6
Reviewed-on: https://go-review.googlesource.com/41673Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This comment is very useful but still refers to the C implementation.
Adapting it for Go is fairly straightforward though.

Change-Id: Ib6dde25f3a18acbce76bb3cffdc29f5ccf43c1f7
Reviewed-on: https://go-review.googlesource.com/41696Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The assembler reordered the operands of some instructions to put the
first operand into From3. Unfortunately this meant that when the
instructions were printed the operands were in a different order than
the assembler would expect as input. For example, 'MVC $8, (R1), (R2)'
would be printed as 'MVC (R1), $8, (R2)'.

Originally this was done to ensure that From contained the source
memory operand. The current compiler no longer requires this and so
this CL simply makes all instructions use the standard order for
operands: From, Reg, From3 and finally To.

Fixes #18295

Change-Id: Ib2b5ec29c647ca7a995eb03dc78f82d99618b092
Reviewed-on: https://go-review.googlesource.com/40299
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Breaks are implicit, and since there is no outer loop this one could not
mean a loop break that was missing a label.

Change-Id: Ie91018db1825aa8285c1aa55c9d28fc7ec7148af
Reviewed-on: https://go-review.googlesource.com/39691
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Mostly unnecessary *testing.T arguments.

Found with github.com/mvdan/unparam.

Change-Id: Ifb955cb88f2ce8784ee4172f4f94d860fa36ae9a
Reviewed-on: https://go-review.googlesource.com/41691
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Now that the os package uses internal/poll on Unix and Windows systems,
it can rely on internal/poll reference counting to ensure that the
file descriptor is not closed until all I/O is complete.

That was already working. This CL completes the job by not trying to
modify the Sysfd field when it might still be used by the I/O routines.

Fixes #7970

Change-Id: I7a3daa1a6b07b7345bdce6f0cd7164bd4eaee952
Reviewed-on: https://go-review.googlesource.com/41674Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This change adds a better asm implementation of addVV for ppc64x, with speedups
up to nearly 3x in the best cases.

benchmark                   old ns/op     new ns/op     delta
BenchmarkAddVV/1-8          7.33          5.81          -20.74%
BenchmarkAddVV/2-8          8.72          6.49          -25.57%
BenchmarkAddVV/3-8          10.5          7.08          -32.57%
BenchmarkAddVV/4-8          12.7          7.57          -40.39%
BenchmarkAddVV/5-8          14.3          8.06          -43.64%
BenchmarkAddVV/10-8         27.6          11.1          -59.78%
BenchmarkAddVV/100-8        218           82.4          -62.20%
BenchmarkAddVV/1000-8       2064          718           -65.21%
BenchmarkAddVV/10000-8      20536         7153          -65.17%
BenchmarkAddVV/100000-8     211004        72403         -65.69%

benchmark                   old MB/s     new MB/s     speedup
BenchmarkAddVV/1-8          8729.74      11006.26     1.26x
BenchmarkAddVV/2-8          14683.65     19707.55     1.34x
BenchmarkAddVV/3-8          18226.96     27103.63     1.49x
BenchmarkAddVV/4-8          20204.50     33805.81     1.67x
BenchmarkAddVV/5-8          22348.64     39694.06     1.78x
BenchmarkAddVV/10-8         23212.74     57631.08     2.48x
BenchmarkAddVV/100-8        29300.07     77629.53     2.65x
BenchmarkAddVV/1000-8       31000.56     89094.54     2.87x
BenchmarkAddVV/10000-8      31163.61     89469.16     2.87x
BenchmarkAddVV/100000-8     30331.16     88393.73     2.91x

It also adds the use of CTR for the loop counter in subVV, instead of
manually updating the loop counter. This is slightly faster.

Change-Id: Ic4b05cad384fd057972d46a5618ed5c3039d7460
Reviewed-on: https://go-review.googlesource.com/41010
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>

As discussion in issue #18293, "MOVW $Imm-16, Reg" was introduced in
ARMv7. It directly encoded the 16-bit immediate into the instruction
instead of put it in the constant pool.

This patch makes the arm assembler choose this form of MOVW if available.

Besides 4 bytes are saved in the constant pool, the go1 benchmark test
also shows a slight improvement.

name                     old time/op    new time/op    delta
BinaryTree17-4              42.7s ± 1%     42.7s ± 1%    ~     (p=0.304 n=50+50)
Fannkuch11-4                24.8s ± 1%     24.8s ± 0%    ~     (p=0.757 n=50+49)
FmtFprintfEmpty-4           875ns ± 1%     873ns ± 2%    ~     (p=0.066 n=44+46)
FmtFprintfString-4         1.43µs ± 1%    1.45µs ± 1%  +1.68%  (p=0.000 n=44+44)
FmtFprintfInt-4            1.52µs ± 1%    1.52µs ± 1%  +0.26%  (p=0.009 n=41+45)
FmtFprintfIntInt-4         2.19µs ± 1%    2.20µs ± 1%  +0.76%  (p=0.000 n=43+46)
FmtFprintfPrefixedInt-4    2.56µs ± 2%    2.53µs ± 1%  -1.03%  (p=0.000 n=45+44)
FmtFprintfFloat-4          4.41µs ± 1%    4.39µs ± 1%  -0.52%  (p=0.000 n=44+44)
FmtManyArgs-4              9.02µs ± 2%    9.04µs ± 1%  +0.27%  (p=0.000 n=46+44)
GobDecode-4                 106ms ± 1%     106ms ± 1%    ~     (p=0.310 n=45+43)
GobEncode-4                88.1ms ± 2%    88.0ms ± 2%    ~     (p=0.648 n=49+50)
Gzip-4                      4.31s ± 1%     4.27s ± 1%  -1.01%  (p=0.000 n=50+50)
Gunzip-4                    618ms ± 1%     608ms ± 1%  -1.65%  (p=0.000 n=45+47)
HTTPClientServer-4          689µs ± 6%     692µs ± 4%  +0.52%  (p=0.038 n=50+47)
JSONEncode-4                282ms ± 2%     280ms ± 1%  -0.75%  (p=0.000 n=46+43)
JSONDecode-4                945ms ± 2%     940ms ± 1%  -0.47%  (p=0.000 n=47+47)
Mandelbrot200-4            49.4ms ± 1%    49.3ms ± 1%    ~     (p=0.163 n=45+45)
GoParse-4                  46.0ms ± 3%    45.5ms ± 2%  -0.95%  (p=0.000 n=49+40)
RegexpMatchEasy0_32-4      1.29µs ± 1%    1.28µs ± 1%  -0.14%  (p=0.005 n=38+45)
RegexpMatchEasy0_1K-4      7.92µs ± 8%    7.75µs ± 6%  -2.12%  (p=0.000 n=47+50)
RegexpMatchEasy1_32-4      1.31µs ± 1%    1.31µs ± 0%    ~     (p=0.282 n=45+48)
RegexpMatchEasy1_1K-4      10.4µs ± 5%    10.4µs ± 3%    ~     (p=0.771 n=50+49)
RegexpMatchMedium_32-4     2.06µs ± 1%    2.07µs ± 1%  +0.35%  (p=0.001 n=44+49)
RegexpMatchMedium_1K-4      533µs ± 1%     532µs ± 1%    ~     (p=0.710 n=43+47)
RegexpMatchHard_32-4       29.7µs ± 1%    29.6µs ± 1%  -0.34%  (p=0.002 n=43+46)
RegexpMatchHard_1K-4        893µs ± 2%     885µs ± 1%  -0.85%  (p=0.000 n=50+45)
Revcomp-4                  85.6ms ± 4%    85.5ms ± 2%    ~     (p=0.683 n=50+50)
Template-4                  1.05s ± 3%     1.04s ± 1%  -1.06%  (p=0.000 n=50+44)
TimeParse-4                7.19µs ± 2%    7.11µs ± 2%  -1.10%  (p=0.000 n=48+46)
TimeFormat-4               13.4µs ± 1%    13.5µs ± 1%    ~     (p=0.056 n=46+49)
[Geo mean]                  747µs          745µs       -0.28%

name                     old speed      new speed      delta
GobDecode-4              7.23MB/s ± 1%  7.22MB/s ± 1%    ~     (p=0.062 n=45+39)
GobEncode-4              8.71MB/s ± 2%  8.72MB/s ± 2%    ~     (p=0.656 n=49+50)
Gzip-4                   4.50MB/s ± 1%  4.55MB/s ± 1%  +1.03%  (p=0.000 n=50+50)
Gunzip-4                 31.4MB/s ± 1%  31.9MB/s ± 1%  +1.67%  (p=0.000 n=45+47)
JSONEncode-4             6.89MB/s ± 2%  6.94MB/s ± 1%  +0.76%  (p=0.000 n=46+43)
JSONDecode-4             2.05MB/s ± 2%  2.06MB/s ± 2%  +0.32%  (p=0.017 n=47+50)
GoParse-4                1.26MB/s ± 3%  1.27MB/s ± 1%  +0.68%  (p=0.000 n=50+48)
RegexpMatchEasy0_32-4    24.9MB/s ± 1%  24.9MB/s ± 1%  +0.13%  (p=0.004 n=38+45)
RegexpMatchEasy0_1K-4     129MB/s ± 7%   132MB/s ± 6%  +2.34%  (p=0.000 n=46+50)
RegexpMatchEasy1_32-4    24.5MB/s ± 1%  24.4MB/s ± 1%    ~     (p=0.252 n=45+48)
RegexpMatchEasy1_1K-4    98.8MB/s ± 4%  98.7MB/s ± 3%    ~     (p=0.771 n=50+49)
RegexpMatchMedium_32-4    485kB/s ± 3%   480kB/s ± 0%  -0.95%  (p=0.000 n=50+38)
RegexpMatchMedium_1K-4   1.92MB/s ± 1%  1.92MB/s ± 1%    ~     (p=0.129 n=43+47)
RegexpMatchHard_32-4     1.08MB/s ± 2%  1.08MB/s ± 1%  +0.38%  (p=0.017 n=46+46)
RegexpMatchHard_1K-4     1.15MB/s ± 2%  1.16MB/s ± 1%  +0.67%  (p=0.001 n=50+49)
Revcomp-4                29.7MB/s ± 4%  29.7MB/s ± 2%    ~     (p=0.682 n=50+50)
Template-4               1.85MB/s ± 3%  1.87MB/s ± 1%  +1.04%  (p=0.000 n=50+44)
[Geo mean]               6.56MB/s       6.60MB/s       +0.47%


Change-Id: Ic2cca90133c27a08d9f1a23c65b0eed5fbd02684
Reviewed-on: https://go-review.googlesource.com/41190
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

s/arm64/amd64/ in previous typo CL 41628

Updates #19938
Updates #18243

Change-Id: I282244ee3c94535f229a87b6246382385ff64428
Reviewed-on: https://go-review.googlesource.com/41675Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Reduces cmd/go by 4464 bytes on amd64.

Removes the duplicate detection of AVX support and
presence of Intel processors.

Change-Id: I4670189951a63760fae217708f68d65e94a30dc5
Reviewed-on: https://go-review.googlesource.com/41570Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Updates #19938
Updates #18243

Change-Id: Ib6e704c0a5d596bdfaa6493902d2528bec55bf16
Reviewed-on: https://go-review.googlesource.com/41628Reviewed-by: Ian Lance Taylor <iant@golang.org>

Implemented low-level time system for windows on hardware (software),
which does not support memory mapped _KSYSTEM_TIME page update.

In particular this problem exists on Wine where _KSYSTEM_TIME
only contains time at the start, and is never modified.

On start we try to detect Wine and if it's so we fallback to
GetSystemTimeAsFileTime() for current time and a monotonic
timer based on QueryPerformanceCounter family of syscalls:
https://msdn.microsoft.com/en-us/library/windows/desktop/dn553408(v=vs.85).aspx

Fixes #18537

Change-Id: I269d22467ed9b0afb62056974d23e731b80c83ed
Reviewed-on: https://go-review.googlesource.com/35710Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Since Pread/Pwrite specify a file offset, using incref is sufficient.
This permits multiple Pread/Pwrite calls in parallel.

Since Pread/Pwrite specify a file offset, it doesn't seem to make
sense to use the poller for them, so don't.

Updates #19586

Change-Id: I676be16bf519b9a45f8e6b1d991c44f10848bc11
Reviewed-on: https://go-review.googlesource.com/41670
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

As Ian said at:
https://github.com/golang/go/issues/19964#issuecomment-296347750

> the -fdebug-prefix-map option is being applied to the debug info but
> not to the initial .file pseudo-op.
>
> My only current thought for how to fix this is that instead of
> compiling $WORK/a/b/foo.c, we should change the command to (cd
> $WORK/a/b && clang -g -c foo.c). We'll still want
> -fdebug-prefix-map, I think, but that should fix the .file
> pseudo-op.

This CL does that.

Fixes #19964

Change-Id: I442b1201cab9e0448fc520ab243ad364d59cd7c3
Reviewed-on: https://go-review.googlesource.com/41629
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Use an original name instead of a symlink's target path.

Fixes #20064

Change-Id: I9be3837a156bdcda0e9e065abbb425d535b27be3
Reviewed-on: https://go-review.googlesource.com/41310Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

When unshare specifies a new namespace, the syscall
package changes / to make namespace changes private.

If a chroot is specified, the unshare must be done first.
If the chroot is done first then the unshare will
not specify the correct /.

A new test is included which test combining chroot
and CLONE_NEWNS; it fails without the patch and works with
it.

Fixes #20103

Change-Id: I86022803c784bd418a30383321f3d64103d95c62
Reviewed-on: https://go-review.googlesource.com/41626Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

For #17541.

Change-Id: I524ab194f32b8b061ce1c9c3e0cd34cc5539358e
Reviewed-on: https://go-review.googlesource.com/39410
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This reduces the size of the ssa export data
by 10%, from 76154 to 67886.

It doesn't appear that #20084, which would do this automatically,
is going to be fixed soon. Do it manually for now.

This speeds up compiling cmd/compile/internal/amd64
and presumably its comrades as well:

name          old time/op       new time/op       delta
CompileAMD64       89.6ms ± 6%       86.7ms ± 5%  -3.29%  (p=0.000 n=49+47)

name          old user-time/op  new user-time/op  delta
CompileAMD64        116ms ± 5%        112ms ± 5%  -3.51%  (p=0.000 n=45+42)

name          old alloc/op      new alloc/op      delta
CompileAMD64       26.7MB ± 0%       25.8MB ± 0%  -3.26%  (p=0.008 n=5+5)

name          old allocs/op     new allocs/op     delta
CompileAMD64         223k ± 0%         213k ± 0%  -4.46%  (p=0.008 n=5+5)

Updates #20084

Change-Id: I49e8951c5bfce63ad2b7f4fc3bfa0868c53114f9
Reviewed-on: https://go-review.googlesource.com/41493
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I4d5c54d2dceabf4630e5e642835b20c8c6890524
Reviewed-on: https://go-review.googlesource.com/41616
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Optimize DecodeString for the common case where most of the input isn't
a newline or a padding character.
Also add some testcases found when fuzzing this implementation against
upstream.
Change Decode benchmark to run with different input sizes.

name                 old time/op    new time/op    delta
DecodeString/2-4       71.5ns ± 4%    70.0ns ± 6%     ~     (p=0.246 n=5+5)
DecodeString/4-4        112ns ±25%      91ns ± 2%     ~     (p=0.056 n=5+5)
DecodeString/8-4        136ns ± 5%     126ns ± 5%   -7.33%  (p=0.016 n=5+5)
DecodeString/64-4       872ns ±29%     652ns ±21%  -25.23%  (p=0.032 n=5+5)
DecodeString/8192-4    90.9µs ±21%    61.0µs ±13%  -32.87%  (p=0.008 n=5+5)

name                 old speed      new speed      delta
DecodeString/2-4     56.0MB/s ± 4%  57.2MB/s ± 6%     ~     (p=0.310 n=5+5)
DecodeString/4-4     73.4MB/s ±23%  87.7MB/s ± 2%     ~     (p=0.056 n=5+5)
DecodeString/8-4     87.8MB/s ± 5%  94.8MB/s ± 5%   +7.98%  (p=0.016 n=5+5)
DecodeString/64-4     103MB/s ±24%   136MB/s ±19%  +32.63%  (p=0.032 n=5+5)
DecodeString/8192-4   122MB/s ±19%   180MB/s ±11%  +47.75%  (p=0.008 n=5+5)

Improves #19636

Change-Id: I39667f4fb682a12b3137946d017ad999553c5780
Reviewed-on: https://go-review.googlesource.com/34950Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

There were a number of places in crypto/x509 that used hardcoded
representations of the ASN.1 NULL type, in both byte slice and
RawValue struct forms. This change adds two new exported vars to
the asn1 package for working with ASN.1 NULL in both its forms, and
converts all usages from the x509 package.

In addition, tests were added to exercise Marshal and Unmarshal on
both vars.

See #19446 for discussion.

Change-Id: I63dbd0835841ccbc810bd6ec794360a84e933f1e
Reviewed-on: https://go-review.googlesource.com/38660
Run-TryBot: Adam Langley <agl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

We can also remove the internal/load import as a result.

Found with honnef.co/go/tools/cmd/unused.

Change-Id: Ie70c5713e7a6f238158804acec07807c14f8e092
Reviewed-on: https://go-review.googlesource.com/41473Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I9cdf6e7da0fb2d5194426eafa61812ea7a85f52f
Reviewed-on: https://go-review.googlesource.com/37161Reviewed-by: Dan Peterson <dpiddy@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Old loops look like this:
   loop:
     CMPQ ...
     JGE exit
     ...
     JMP loop
   exit:

New loops look like this:
    JMP entry
  loop:
    ...
  entry:
    CMPQ ...
    JLT loop

This removes one instruction (the unconditional jump) from
the inner loop.
Kinda surprisingly, it matters.

This is a bit different than the peeling that the old obj
library did in that we don't duplicate the loop exit test.
We just jump to the test.  I'm not sure if it is better or
worse to do that (peeling gets rid of the JMP but means more
code duplication), but this CL is certainly a much simpler
compiler change, so I'll try this way first.

The obj library used to do peeling before
CL https://go-review.googlesource.com/c/36205 turned it off.

Fixes #15837 (remove obj instruction reordering)
The reordering is already removed, this CL implements the only
part of that reordering that we'd like to keep.

Fixes #14758 (append loop)
name    old time/op    new time/op    delta
Foo-12     817ns ± 4%     538ns ± 0%  -34.08%   (p=0.000 n=10+9)
Bar-12     850ns ±11%     570ns ±13%  -32.88%  (p=0.000 n=10+10)

Update #19595 (BLAS slowdown)
name                       old time/op  new time/op  delta
DgemvMedMedNoTransIncN-12  13.2µs ± 9%  10.2µs ± 1%  -22.26%  (p=0.000 n=9+9)

Fixes #19633 (append loop)
name    old time/op    new time/op    delta
Foo-12     810ns ± 1%     540ns ± 0%  -33.30%   (p=0.000 n=8+9)

Update #18977 (Fannkuch11 regression)
name         old time/op    new time/op    delta
Fannkuch11-8                2.80s ± 0%     3.01s ± 0%  +7.47%   (p=0.000 n=9+10)
This one makes no sense.  There's strictly 1 less instruction in the
inner loop (17 instead of 18).  They are exactly the same instructions
except for the JMP that has been elided.

go1 benchmarks generally don't look very impressive.  But the gains for the
specific issues above make this CL still probably worth it.
name                      old time/op    new time/op    delta
BinaryTree17-8              2.32s ± 0%     2.34s ± 0%  +1.14%    (p=0.000 n=9+7)
Fannkuch11-8                2.80s ± 0%     3.01s ± 0%  +7.47%   (p=0.000 n=9+10)
FmtFprintfEmpty-8          44.1ns ± 1%    46.1ns ± 1%  +4.53%  (p=0.000 n=10+10)
FmtFprintfString-8         67.8ns ± 0%    74.4ns ± 1%  +9.80%   (p=0.000 n=10+9)
FmtFprintfInt-8            74.9ns ± 0%    78.4ns ± 0%  +4.67%   (p=0.000 n=8+10)
FmtFprintfIntInt-8          117ns ± 1%     123ns ± 1%  +4.69%   (p=0.000 n=9+10)
FmtFprintfPrefixedInt-8     160ns ± 1%     146ns ± 0%  -8.22%   (p=0.000 n=8+10)
FmtFprintfFloat-8           214ns ± 0%     206ns ± 0%  -3.91%    (p=0.000 n=8+8)
FmtManyArgs-8               468ns ± 0%     497ns ± 1%  +6.09%   (p=0.000 n=8+10)
GobDecode-8                6.16ms ± 0%    6.21ms ± 1%  +0.76%   (p=0.000 n=9+10)
GobEncode-8                4.90ms ± 0%    4.92ms ± 1%  +0.37%   (p=0.028 n=9+10)
Gzip-8                      209ms ± 0%     212ms ± 0%  +1.33%  (p=0.000 n=10+10)
Gunzip-8                   36.6ms ± 0%    38.0ms ± 1%  +4.03%    (p=0.000 n=9+9)
HTTPClientServer-8         84.2µs ± 0%    86.0µs ± 1%  +2.14%    (p=0.000 n=9+9)
JSONEncode-8               13.6ms ± 3%    13.8ms ± 1%  +1.55%   (p=0.003 n=9+10)
JSONDecode-8               53.2ms ± 5%    52.9ms ± 0%    ~     (p=0.280 n=10+10)
Mandelbrot200-8            3.78ms ± 0%    3.78ms ± 1%    ~      (p=0.661 n=10+9)
GoParse-8                  2.89ms ± 0%    2.94ms ± 2%  +1.50%  (p=0.000 n=10+10)
RegexpMatchEasy0_32-8      68.5ns ± 2%    68.9ns ± 1%    ~     (p=0.136 n=10+10)
RegexpMatchEasy0_1K-8       220ns ± 1%     225ns ± 1%  +2.41%  (p=0.000 n=10+10)
RegexpMatchEasy1_32-8      64.7ns ± 0%    64.5ns ± 0%  -0.28%  (p=0.042 n=10+10)
RegexpMatchEasy1_1K-8       348ns ± 1%     355ns ± 0%  +1.90%  (p=0.000 n=10+10)
RegexpMatchMedium_32-8      102ns ± 1%     105ns ± 1%  +2.95%  (p=0.000 n=10+10)
RegexpMatchMedium_1K-8     33.1µs ± 3%    32.5µs ± 0%  -1.75%  (p=0.000 n=10+10)
RegexpMatchHard_32-8       1.71µs ± 1%    1.70µs ± 1%  -0.84%   (p=0.002 n=10+9)
RegexpMatchHard_1K-8       51.1µs ± 0%    50.8µs ± 1%  -0.48%  (p=0.004 n=10+10)
Revcomp-8                   411ms ± 1%     402ms ± 0%  -2.22%   (p=0.000 n=10+9)
Template-8                 61.8ms ± 1%    59.7ms ± 0%  -3.44%    (p=0.000 n=9+9)
TimeParse-8                 306ns ± 0%     318ns ± 0%  +3.83%  (p=0.000 n=10+10)
TimeFormat-8                320ns ± 0%     318ns ± 1%  -0.53%   (p=0.012 n=7+10)

Change-Id: Ifaf29abbe5874e437048e411ba8f7cfbc9e1c94b
Reviewed-on: https://go-review.googlesource.com/38431
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Updates #20076

Change-Id: I4eb98abbb49174cc6433e5da2c3660893ef88fd1
Reviewed-on: https://go-review.googlesource.com/41615
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This will be used in the future to control backend concurrency.
See CL 40693.

In the meantime, make it a no-op.
This should fix the linux-amd64-racecompile builders.

Change-Id: Ibf3b2a7fff6f8f8c94f5fafb26e0500a51c8a4a6
Reviewed-on: https://go-review.googlesource.com/41614
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Databases have the following concepts: Statement, Batch, and Session.

A statement is often a single line like:
SELECT Amount from Account where ID = 50;

A batch is one or more statements submitted together for the query
to process. It may be a DELETE, INSERT, two UPDATES and a SELECT in
a single query text.

A session is usually represented by a single database connection.
This often is an issue when dealing with scopes in databases.
Temporary tables and variables can have batch, session, or global
scope depending on the syntax, database, and use.

Furthermore, some databases (sybase and derivatives in perticular)
that prevent certain statements from being in the same batch
and may necessitate being in the same session.

By allowing users to extract a Conn from the database they can manage
session on their own without hacking around it by making connection
pools of single connections (a real workaround presented in issue).
It is tempting to just use a transaction, but this isn't always
desirable or an option if running an interactive session or
alter script set that itself starts transactions.

Fixes #18081

Change-Id: I9bdf0796632c48d4bcaef3624c629641984ffaf2
Reviewed-on: https://go-review.googlesource.com/40694Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I954b0300554786b7026996a21acfec3b6f205e75
Reviewed-on: https://go-review.googlesource.com/41512
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I7a18798180405504dc064424d63dac49634168fb
Reviewed-on: https://go-review.googlesource.com/41530Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We have dedicated asm implementation of sincos only on 386 and amd64,
on everything else we are just jumping to generic version.
However amd64 version is actually slower than generic one:

Sincos-6               34.4ns ± 0%   24.8ns ± 0%  -27.79%  (p=0.000 n=8+10)

So remove all sincos*.s and keep only generic and 386.

Updates #19819

Change-Id: I7eefab35743729578264f52f6d23ee2c227c92a5
Reviewed-on: https://go-review.googlesource.com/41200
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

This change adds line position tests for several yyerror calls in the
typechecker that are currently not tested in any way.

Untested yyerror calls were found by replacing them with

  yerrorl(src.NoXPos, ...)

(thus destroying position information in the error), and then running
the test suite. No failures means no test coverage for the relevant
yyerror call.

For #19683

Change-Id: Iedb3d2f02141b332e9bfa76dbf5ae930ad2fddc3
Reviewed-on: https://go-review.googlesource.com/41477
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

doubleselect.go defines a flag to control the number of iterations,
but never called flag.Parse so it was unusable.

Change-Id: Ib5d0c7119e7f7c9a808dcc02d0d9cc6ba5bbc16e
Reviewed-on: https://go-review.googlesource.com/41299Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>