Currently these are labeled "MARK", which was accurate in the STW
collector, but these really indicate mark termination now, since
marking happens for the full duration of the concurrent GC. Re-label
them as "MARK TERMINATION" to clarify this.

Change-Id: Ie98bd961195acde49598b4fa3f9e7d90d757c0a6
Reviewed-on: https://go-review.googlesource.com/30018Reviewed-by: Dmitry Vyukov <dvyukov@google.com>

Currently, the process-wide GC state is attributed to the P that
happened to perform the allocation that exceeded the GC trigger. This
is pretty arbitrary and makes it hard to see when GC is running since
the GC spans are intermingled with a lot of other trace noise.

The current display is particularly confusing because it creates three
sub-rows in the P row that can overlap each other. Usually a P has
just two sub-rows: one showing the current G and another showing that
G's activity. However, because GC is attributed to a proc, it winds up
as a third row that neither subsumes nor is subsumed by any other row.
This in turn screws up the trace's layout and results in overlapping
events.

Fix these problems by creating a new dedicated row like the existing
"Network" and "Timer" rows and displaying process-wide GC events in
this row. Mark termination and sweep events still appear in their
respective P rows because these are meaningfully attributed.

Change-Id: Ie1a1c6cf8c446e4b043f10f3968f91ff1b546d15
Reviewed-on: https://go-review.googlesource.com/30017Reviewed-by: Dmitry Vyukov <dvyukov@google.com>

When GC is disabled, we set gcpercent to -1. However, we still use
gcpercent to compute several values, such as next_gc and gc_trigger.
These calculations are meaningless when gcpercent is -1 and result in
meaningless values. This is okay in a sense because we also never use
these values if gcpercent is -1, but they're confusing when exposed to
the user, for example via MemStats or the execution trace. It's
particularly unfortunate in the execution trace because it attempts to
plot the underflowed value of next_gc, which scales all useful
information in the heap row into oblivion.

Fix this by making next_gc ^0 when gcpercent < 0. This has the
advantage of being true in a way: next_gc is effectively infinite when
gcpercent < 0. We can also detect this special value when updating the
execution trace and report next_gc as 0 so it doesn't blow up the
display of the heap line.

Change-Id: I4f366e4451f8892a4908da7b2b6086bdc67ca9a9
Reviewed-on: https://go-review.googlesource.com/30016Reviewed-by: Rick Hudson <rlh@golang.org>

Not sure why it was ever disabled (early SSA work?) but it passes now.

Change-Id: I76439cacdbd286ce077f7e08c4d0663396a0cd8f
Reviewed-on: https://go-review.googlesource.com/30672Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

No point doing this check all the time.

Fixes #15621

Change-Id: I1966c061986fe98fe9ebe146d6b9738c13cef724
Reviewed-on: https://go-review.googlesource.com/30670Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This CL makes minor adjustment to the handling of spaces and newlines
and then documents the result.

The semantic adjustment mainly concerns the handling of a run of
spaces following a newline in the format, like in "\n ".
Previously, that run of spaces was ignored entirely, leading to paradoxes
like the format "1 \n 2" not matching itself as input.
Now, spaces following a newline in the format match zero or more
spaces following the corresponding newline in the input.

The changes to the test suite show how minor the semantic adjustments are
and how they make the behavior more regular than previously.

This CL also updates the documentation to explain the handling of
spaces more precisely, incorporating the draft from CL 17723 but
describing the newly introduced behavior.

Fixes #13565.

Change-Id: I129666e9ba42de3c28b67f75cb47488e9a4c1867
Reviewed-on: https://go-review.googlesource.com/30611Reviewed-by: Rob Pike <r@golang.org>

There are no semantic changes here, just tests to establish
the status quo. A followup CL will make some semantic changes,
the (limited) scope of which should be clear from the number of
tests that change.

For #13565.

Change-Id: I960749cf59d4dfe39c324875bcc575096654f883
Reviewed-on: https://go-review.googlesource.com/30610
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Anonymous pointer and slice types are very common and identical
anyway, so just reuse them rather than allocating new ones everywhere
they appear.

Turns out to be a small code/stack size win because SSA relies on
gc.Type identity for reusing temporary stack slots:

   text	   data	    bss	    dec	    hex	filename
6453005	 231643	 146328	6830976	 683b80	go.old
6446660	 231643	 146328	6824631	 6822b7	go.new

Saves on memory usage during compile time too, and maybe a small CPU
time win, but the benchmarks are pretty noisy:

name       old time/op     new time/op     delta
Template       342ms ± 8%      339ms ± 9%    ~           (p=0.332 n=99+99)
Unicode        183ms ± 9%      181ms ±11%    ~           (p=0.274 n=95+98)
GoTypes        1.05s ± 4%      1.04s ± 3%  -1.22%        (p=0.000 n=97+95)
Compiler       4.49s ± 7%      4.46s ± 6%    ~           (p=0.058 n=96+91)

name       old user-ns/op  new user-ns/op  delta
Template        520M ±17%       522M ±20%    ~          (p=0.544 n=98+100)
Unicode         331M ±27%       327M ±30%    ~           (p=0.615 n=98+98)
GoTypes        1.54G ±10%      1.53G ±12%    ~          (p=0.173 n=99+100)
Compiler       6.33G ±10%      6.33G ±10%    ~           (p=0.682 n=98+98)

name       old alloc/op    new alloc/op    delta
Template      44.5MB ± 0%     44.1MB ± 0%  -0.80%        (p=0.000 n=97+99)
Unicode       37.5MB ± 0%     37.3MB ± 0%  -0.44%       (p=0.000 n=98+100)
GoTypes        126MB ± 0%      124MB ± 0%  -1.41%        (p=0.000 n=98+99)
Compiler       518MB ± 0%      508MB ± 0%  -1.90%       (p=0.000 n=98+100)

name       old allocs/op   new allocs/op   delta
Template        441k ± 0%       434k ± 0%  -1.76%       (p=0.000 n=100+97)
Unicode         368k ± 0%       365k ± 0%  -0.69%        (p=0.000 n=99+99)
GoTypes        1.26M ± 0%      1.23M ± 0%  -2.27%       (p=0.000 n=100+99)
Compiler       4.60M ± 0%      4.46M ± 0%  -2.96%       (p=0.000 n=100+99)

Change-Id: I94abce5c57aed0f9c48f567b3ac24c627d4c7c91
Reviewed-on: https://go-review.googlesource.com/30632
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

On 64-bit big-endian GNU/Linux machines we need to treat sigset as a
single uint64, not as a pair of uint32 values. This fix was already made
for s390x, but not for ppc64 (which is big-endian--the little endian
version is known as ppc64le). So copy os_linux_390.x to
os_linux_be64.go, and use build constraints as needed.

Fixes #17361

Change-Id: Ia0eb18221a8f5056bf17675fcfeb010407a13fb0
Reviewed-on: https://go-review.googlesource.com/30602
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This simply documents the status quo accepted by cmd/compile, gccgo,
and go/types. The new language matches the language used for indices
of index expressions for arrays and slices.

Fixes #16679.

Change-Id: I65447889fbda9d222f2a9e6c10334d1b38c555f0
Reviewed-on: https://go-review.googlesource.com/30474Reviewed-by: Rob Pike <r@golang.org>

Also, document behavior explicitly for all SetString implementations.

Fixes #17001.

Change-Id: Iccc882b4bc7f8b61b6092f330e405c146a80dc98
Reviewed-on: https://go-review.googlesource.com/30472Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Updates #17366

Change-Id: Ia4bd3c74c48b85f186586184a7c2b66d3b80fc9c
Reviewed-on: https://go-review.googlesource.com/30596
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Updates #16360

Change-Id: I941519981ff5bda3a113e14fa6be718eb4d2bf83
Reviewed-on: https://go-review.googlesource.com/30554
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #15247

Change-Id: I942fb2eacd1b54bab66cc147a6b047a3ffce0b84
Reviewed-on: https://go-review.googlesource.com/30595Reviewed-by: Russ Cox <rsc@golang.org>

Handle NTFS timestamp, UNIX timestamp, Extended extra timestamp.
Writer supports only Extended extra timestamp field, matching most
zip creators.

Fixes #10242.

Change-Id: Id665db274e63def98659231391fb77392267ac1e
Reviewed-on: https://go-review.googlesource.com/18274
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

We insert extensions when lowering comparisons and they were
blocking constant folding.

Change-Id: I804bbf91c7606612ffe921a90853844a57e55955
Reviewed-on: https://go-review.googlesource.com/30541Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

AddDate now retrieves location from t.Location() to ensure that
it never calls Date with a nil location.

Added test for this bug on all Time's methods

Fixes #15852

Change-Id: Id2a222af56993f741ad0b802a2c3b89e8e463926
Reviewed-on: https://go-review.googlesource.com/23561Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>

It tests the behavior of the old deleted compiler.

Fixes #17362.

Change-Id: Ia2fdec734c5cbe724a9de562ed71598f67244ab3
Reviewed-on: https://go-review.googlesource.com/30593Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: Id2a9fc1e9e70eaf5f25ddc7476061e06abcf60e4
Reviewed-on: https://go-review.googlesource.com/30573Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Fixes #17281.

Change-Id: I4e639998dbe3baa98879f1becc37d7c4d19351e7
Reviewed-on: https://go-review.googlesource.com/30473Reviewed-by: Alan Donovan <adonovan@google.com>

Fixes #17354.

Change-Id: I0e018c8c3e791fc6cc1925dbbc18c2151ba9a111
Reviewed-on: https://go-review.googlesource.com/30539
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Using 387 mode was computing it without underflow to zero,
apparently due to an 80-bit intermediate. Avoid underflow even
with 64-bit floats.

This eliminates the TODOs in the test suite.

Fixes linux-386-387 build and fixes #11441.

Change-Id: I8abaa63bfdf040438a95625d1cb61042f0302473
Reviewed-on: https://go-review.googlesource.com/30540
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Struct fields can be suppressed in JSON serialization by "-" tags, but
that doesn't preclude generation of "-" object keys.
Document and verify the mechanism for doing so.

Change-Id: I7f60e1759cfee15cb7b2447cd35fab91c5b004e6
Reviewed-on: https://go-review.googlesource.com/21204
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Deletes the following s390x instructions:

 - ADDME
 - ADDZE
 - SUBME
 - SUBZE

They appear to be emulated PPC instructions left over from the
porting process and I don't think they will ever be useful.

Change-Id: I9b1ba78019dbd1218d0c8f8ea2903878802d1990
Reviewed-on: https://go-review.googlesource.com/30538
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

    Use AVX if available on 4th generation of Intel(TM) Core(TM) processors.

    (collected on E5 2609v3 @1.9GHz)
    name                        old speed      new speed       delta
    Memmove/1-6                  158MB/s ± 0%    172MB/s ± 0%    +9.09% (p=0.000 n=16+16)
    Memmove/2-6                  316MB/s ± 0%    345MB/s ± 0%    +9.09% (p=0.000 n=18+16)
    Memmove/3-6                  517MB/s ± 0%    517MB/s ± 0%      ~ (p=0.445 n=16+16)
    Memmove/4-6                  687MB/s ± 1%    690MB/s ± 0%    +0.35% (p=0.000 n=20+17)
    Memmove/5-6                  729MB/s ± 0%    729MB/s ± 0%    +0.01% (p=0.000 n=16+18)
    Memmove/6-6                  875MB/s ± 0%    875MB/s ± 0%    +0.01% (p=0.000 n=18+18)
    Memmove/7-6                 1.02GB/s ± 0%   1.02GB/s ± 1%      ~ (p=0.139 n=19+20)
    Memmove/8-6                 1.26GB/s ± 0%   1.26GB/s ± 0%    +0.00% (p=0.000 n=18+18)
    Memmove/9-6                 1.42GB/s ± 0%   1.42GB/s ± 0%    +0.00% (p=0.000 n=17+18)
    Memmove/10-6                1.58GB/s ± 0%   1.58GB/s ± 0%    +0.00% (p=0.000 n=19+19)
    Memmove/11-6                1.74GB/s ± 0%   1.74GB/s ± 0%    +0.00% (p=0.001 n=18+17)
    Memmove/12-6                1.90GB/s ± 0%   1.90GB/s ± 0%    +0.00% (p=0.000 n=19+19)
    Memmove/13-6                2.05GB/s ± 0%   2.05GB/s ± 0%    +0.00% (p=0.000 n=18+19)
    Memmove/14-6                2.21GB/s ± 0%   2.21GB/s ± 0%    +0.00% (p=0.000 n=16+20)
    Memmove/15-6                2.37GB/s ± 0%   2.37GB/s ± 0%    +0.00% (p=0.004 n=19+20)
    Memmove/16-6                2.53GB/s ± 0%   2.53GB/s ± 0%    +0.00% (p=0.000 n=16+16)
    Memmove/32-6                4.67GB/s ± 0%   4.67GB/s ± 0%    +0.00% (p=0.000 n=17+17)
    Memmove/64-6                8.67GB/s ± 0%   8.64GB/s ± 0%    -0.33% (p=0.000 n=18+17)
    Memmove/128-6               12.6GB/s ± 0%   11.6GB/s ± 0%    -8.05% (p=0.000 n=16+19)
    Memmove/256-6               16.3GB/s ± 0%   16.6GB/s ± 0%    +1.66% (p=0.000 n=20+18)
    Memmove/512-6               21.5GB/s ± 0%   24.4GB/s ± 0%   +13.35% (p=0.000 n=18+17)
    Memmove/1024-6              24.7GB/s ± 0%   33.7GB/s ± 0%   +36.12% (p=0.000 n=18+18)
    Memmove/2048-6              27.3GB/s ± 0%   43.3GB/s ± 0%   +58.77% (p=0.000 n=19+17)
    Memmove/4096-6              37.5GB/s ± 0%   50.5GB/s ± 0%   +34.56% (p=0.000 n=19+19)
    MemmoveUnalignedDst/1-6      135MB/s ± 0%    146MB/s ± 0%    +7.69% (p=0.000 n=16+14)
    MemmoveUnalignedDst/2-6      271MB/s ± 0%    292MB/s ± 0%    +7.69% (p=0.000 n=18+18)
    MemmoveUnalignedDst/3-6      438MB/s ± 0%    438MB/s ± 0%      ~ (p=0.352 n=16+19)
    MemmoveUnalignedDst/4-6      584MB/s ± 0%    584MB/s ± 0%      ~ (p=0.876 n=17+17)
    MemmoveUnalignedDst/5-6      631MB/s ± 1%    632MB/s ± 0%    +0.25% (p=0.000 n=20+17)
    MemmoveUnalignedDst/6-6      759MB/s ± 0%    759MB/s ± 0%    +0.00% (p=0.000 n=19+16)
    MemmoveUnalignedDst/7-6      885MB/s ± 0%    883MB/s ± 1%      ~ (p=0.647 n=18+20)
    MemmoveUnalignedDst/8-6     1.08GB/s ± 0%   1.08GB/s ± 0%    +0.00% (p=0.035 n=19+18)
    MemmoveUnalignedDst/9-6     1.22GB/s ± 0%   1.22GB/s ± 0%      ~ (p=0.251 n=18+17)
    MemmoveUnalignedDst/10-6    1.35GB/s ± 0%   1.35GB/s ± 0%      ~ (p=0.327 n=17+18)
    MemmoveUnalignedDst/11-6    1.49GB/s ± 0%   1.49GB/s ± 0%      ~ (p=0.531 n=18+19)
    MemmoveUnalignedDst/12-6    1.63GB/s ± 0%   1.63GB/s ± 0%      ~ (p=0.886 n=19+18)
    MemmoveUnalignedDst/13-6    1.76GB/s ± 0%   1.76GB/s ± 1%    -0.24% (p=0.006 n=18+20)
    MemmoveUnalignedDst/14-6    1.90GB/s ± 0%   1.90GB/s ± 0%      ~ (p=0.818 n=20+19)
    MemmoveUnalignedDst/15-6    2.03GB/s ± 0%   2.03GB/s ± 0%      ~ (p=0.294 n=17+16)
    MemmoveUnalignedDst/16-6    2.17GB/s ± 0%   2.17GB/s ± 0%      ~ (p=0.602 n=16+18)
    MemmoveUnalignedDst/32-6    4.05GB/s ± 0%   4.05GB/s ± 0%    +0.00% (p=0.010 n=18+17)
    MemmoveUnalignedDst/64-6    7.59GB/s ± 0%   7.59GB/s ± 0%    +0.00% (p=0.022 n=18+16)
    MemmoveUnalignedDst/128-6   11.1GB/s ± 0%   11.4GB/s ± 0%    +2.79% (p=0.000 n=18+17)
    MemmoveUnalignedDst/256-6   16.4GB/s ± 0%   16.7GB/s ± 0%    +1.59% (p=0.000 n=20+17)
    MemmoveUnalignedDst/512-6   15.7GB/s ± 0%   21.3GB/s ± 0%   +35.87% (p=0.000 n=18+20)
    MemmoveUnalignedDst/1024-6  16.0GB/s ±20%   31.5GB/s ± 0%   +96.93% (p=0.000 n=20+14)
    MemmoveUnalignedDst/2048-6  19.6GB/s ± 0%   42.1GB/s ± 0%  +115.16% (p=0.000 n=17+18)
    MemmoveUnalignedDst/4096-6  6.41GB/s ± 0%  33.18GB/s ± 0%  +417.56% (p=0.000 n=17+18)
    MemmoveUnalignedSrc/1-6      171MB/s ± 0%    166MB/s ± 0%    -3.33% (p=0.000 n=19+16)
    MemmoveUnalignedSrc/2-6      343MB/s ± 0%    342MB/s ± 1%    -0.41% (p=0.000 n=17+20)
    MemmoveUnalignedSrc/3-6      508MB/s ± 0%    493MB/s ± 1%    -2.90% (p=0.000 n=17+17)
    MemmoveUnalignedSrc/4-6      677MB/s ± 0%    660MB/s ± 2%    -2.55% (p=0.000 n=17+20)
    MemmoveUnalignedSrc/5-6      790MB/s ± 0%    790MB/s ± 0%      ~ (p=0.139 n=17+17)
    MemmoveUnalignedSrc/6-6      948MB/s ± 0%    946MB/s ± 1%      ~ (p=0.330 n=17+19)
    MemmoveUnalignedSrc/7-6     1.11GB/s ± 0%   1.11GB/s ± 0%    -0.05% (p=0.026 n=17+17)
    MemmoveUnalignedSrc/8-6     1.38GB/s ± 0%   1.38GB/s ± 0%      ~ (p=0.091 n=18+16)
    MemmoveUnalignedSrc/9-6     1.42GB/s ± 0%   1.40GB/s ± 1%    -1.04% (p=0.000 n=19+20)
    MemmoveUnalignedSrc/10-6    1.58GB/s ± 0%   1.56GB/s ± 1%    -1.15% (p=0.000 n=18+19)
    MemmoveUnalignedSrc/11-6    1.73GB/s ± 0%   1.71GB/s ± 1%    -1.30% (p=0.000 n=20+20)
    MemmoveUnalignedSrc/12-6    1.89GB/s ± 0%   1.87GB/s ± 1%    -1.18% (p=0.000 n=17+20)
    MemmoveUnalignedSrc/13-6    2.05GB/s ± 0%   2.02GB/s ± 1%    -1.18% (p=0.000 n=17+20)
    MemmoveUnalignedSrc/14-6    2.21GB/s ± 0%   2.18GB/s ± 1%    -1.14% (p=0.000 n=17+20)
    MemmoveUnalignedSrc/15-6    2.36GB/s ± 0%   2.34GB/s ± 1%    -1.04% (p=0.000 n=17+20)
    MemmoveUnalignedSrc/16-6    2.52GB/s ± 0%   2.49GB/s ± 1%    -1.26% (p=0.000 n=19+20)
    MemmoveUnalignedSrc/32-6    4.82GB/s ± 0%   4.61GB/s ± 0%    -4.40% (p=0.000 n=19+20)
    MemmoveUnalignedSrc/64-6    5.03GB/s ± 4%   7.97GB/s ± 0%   +58.55% (p=0.000 n=20+16)
    MemmoveUnalignedSrc/128-6   11.1GB/s ± 0%   11.2GB/s ± 0%    +0.52% (p=0.000 n=17+18)
    MemmoveUnalignedSrc/256-6   16.5GB/s ± 0%   16.4GB/s ± 0%    -0.10% (p=0.000 n=20+18)
    MemmoveUnalignedSrc/512-6   21.0GB/s ± 0%   22.1GB/s ± 0%    +5.48% (p=0.000 n=14+17)
    MemmoveUnalignedSrc/1024-6  24.9GB/s ± 0%   31.9GB/s ± 0%   +28.20% (p=0.000 n=19+20)
    MemmoveUnalignedSrc/2048-6  23.3GB/s ± 0%   33.8GB/s ± 0%   +45.22% (p=0.000 n=17+19)
    MemmoveUnalignedSrc/4096-6  37.3GB/s ± 0%   42.7GB/s ± 0%   +14.30% (p=0.000 n=17+17)

Change-Id: Id66aa3e499ccfb117cb99d623ef326b50d057b64
Reviewed-on: https://go-review.googlesource.com/29590
Run-TryBot: Denis Nagorny <denis.nagorny@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

Adds the following instructions and uses them in the SSA backend:

 - ANDW
 - ORW
 - XORW

The instruction encodings for 32-bit operations are typically shorter,
particularly when an immediate is used. For example, XORW $-1, R1
only requires one instruction, whereas XOR requires two.

Also removes some unused instructions (that were emulated):

 - ANDN
 - NAND
 - ORN
 - NOR

Change-Id: Iff2a16f52004ba498720034e354be9771b10cac4
Reviewed-on: https://go-review.googlesource.com/30291Reviewed-by: Cherry Zhang <cherryyz@google.com>

Better to just rematerialize them when needed instead of
cross-register spilling or other techniques for keeping them in
registers.

This helps for amd64 code that does 1 << x. It is better to do
  loop:
    MOVQ $1, AX  // materialize arg to SLLQ
    SLLQ CX, AX
    ...
    goto loop
than to do
  MOVQ $1, AX    // materialize outsize of loop
  loop:
    MOVQ AX, DX  // save value that's about to be clobbered
    SLLQ CX, AX
    MOVQ DX, AX  // move it back to the correct register
    goto loop

Update #16092

Change-Id: If7ac290208f513061ebb0736e8a79dcb0ba338c0
Reviewed-on: https://go-review.googlesource.com/30471
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

The CgoExternalThreadSIGPROF test starts a thread at constructor time
that does a busy loop. That can throw off some other tests. So only
build that code if testprogcgo is built with the tag threadprof, and
adjust the tests that use that code to pass that build tag.

This revealed that the CgoPprofThread test was not testing what it
should have, as it never actually started the cpuHog thread. It was
passing because of the busy loop thread. Fix it to start the thread as
intended.

Change-Id: I087a9e4fc734a86be16a287456441afac5676beb
Reviewed-on: https://go-review.googlesource.com/30362
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Currently if you declare a type overwriting a predeclared type
and export methods on it they will be exposed in godoc, even
though the type itself is not exported. This corrects that
by making all methods on these types hidden, since that's
the expected output.

Fixes #9860

Change-Id: I14037bdcef1b4bbefcf299a143bac8bf363718e0
Reviewed-on: https://go-review.googlesource.com/20610Reviewed-by: Russ Cox <rsc@golang.org>

It is pretty confusing when there are Go files ignored for mismatching
build tags and similar and we output "no buildable Go files" without
giving any other information about some Go files have been ignored.

Fixes #17008.

Change-Id: I1766ee86a9a7a72f6694deae3f73b47bfc9d0be5
Reviewed-on: https://go-review.googlesource.com/29113
Run-TryBot: Jaana Burcu Dogan <jbd@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Suppose you have already downloaded "foo.bar/baz", where the repo
is for all of foo.bar/, and you then "go get -u foo.bar/...".
The command-line wildcard expands to foo.bar/baz,
and go get updates the foo.bar/ repo.
Suppose that the repo update brought in foo.bar/quux,
though, which depends on other.site/bar.
Download does not consider foo.bar/quux, since it's
only looking at foo.bar/baz, so it didn't download other.site/bar.
After the download, we call importPaths(args) to decide what to install.
That call was reevaluating the original wildcard with the new repo
and matching foo.bar/quux, which was missing its dependency
other.site/bar, causing a build failure.

The fix in this CL is to remember the pre-download expansion
of the argument list and pass it to the installer. Then only the things
we tried to download get installed.

The case where foo.bar/ is not even checked out yet continues to work,
because in that case we leave the wildcard in place, and download
reevaluates it during the download.

The fix in this CL may not be the right long-term fix, but it is at least a fix.
It may be that download should be passed all the original wildcards
so that it can reexpand them as new code is downloaded, ideally reaching
a fixed point. That can be left for another day.

In short:

- The problem is that the "install" half of "go get" was trying to install
  more than the "download" half was properly downloading.
- The fix in this CL is to install just what was downloaded (install less).
- It may be that a future CL should instead download what will be installed (download more).

Fixes #14450.

Change-Id: Ia1984761d24439549b7cff322bc0dbc262c1a653
Reviewed-on: https://go-review.googlesource.com/19892
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This updates runtime/memclr_ppc64x.s to improve performance,
by unrolling loops for larger clears.

Fixes #17348

benchmark                    old MB/s     new MB/s     speedup
BenchmarkMemclr/5-80         199.71       406.63       2.04x
BenchmarkMemclr/16-80        693.66       1817.41      2.62x
BenchmarkMemclr/64-80        2309.35      5793.34      2.51x
BenchmarkMemclr/256-80       5428.18      14765.81     2.72x
BenchmarkMemclr/4096-80      8611.65      27191.94     3.16x
BenchmarkMemclr/65536-80     8736.69      28604.23     3.27x
BenchmarkMemclr/1M-80        9304.94      27600.09     2.97x
BenchmarkMemclr/4M-80        8705.66      27589.64     3.17x
BenchmarkMemclr/8M-80        8575.74      23631.04     2.76x
BenchmarkMemclr/16M-80       8443.10      19240.68     2.28x
BenchmarkMemclr/64M-80       8390.40      9493.04      1.13x
BenchmarkGoMemclr/5-80       263.05       630.37       2.40x
BenchmarkGoMemclr/16-80      904.33       1148.49      1.27x
BenchmarkGoMemclr/64-80      2830.20      8756.70      3.09x
BenchmarkGoMemclr/256-80     6064.59      20299.46     3.35x

Change-Id: Ic76c9183c8b4129ba3df512ca8b0fe6bd424e088
Reviewed-on: https://go-review.googlesource.com/30373
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <munday@ca.ibm.com>
Reviewed-by: David Chase <drchase@google.com>

RHEL 7 introduces a new tool, update-ca-trust(8), which places the
certificate bundle in a new location. Add this path to the list of
locations that are searched for the certificate bundle.

Fixes #15749

Change-Id: Idc97f885ee48ef085f1eb4dacbd1c2cf55f94ff5
Reviewed-on: https://go-review.googlesource.com/30375Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #13485.

Change-Id: I11dd15c7d14fc19d42a3b48427a4cc1208b18e6a
Reviewed-on: https://go-review.googlesource.com/30456Reviewed-by: Matthew Dempsky <mdempsky@google.com>

This reverts commit 59320c39.

Reasons:
This CL was causing failures on a large regression test that we run
within Google. The issues arises from two bugs in the CL:
* The CL dropped support for ';' as a delimiter (see https://golang.org/issue/2210)
* The handling of an empty string caused an empty record to be added when
no record was added (see https://golang.org/cl/30454 for my attempted fix)

The logic being added is essentially a variation of url.ParseQuery,
but altered to accept an io.Reader instead of a string.
Since it is duplicated (but modified) logic, there needs to be good
tests to ensure that it's implementation doesn't drift in functionality
from url.ParseQuery. Fixing the above issues and adding the associated
regression tests leads to >100 lines of codes.
For a 4% reduction in CPU time, I think this complexity and duplicated
logic is not worth the effort.

As such, I am abandoning my efforts to fix the existing issues and
believe that reverting CL/20301 is the better course of action.

Updates #14655

Change-Id: Ibb5be0a5b48a16c46337e213b79467fcafee69df
Reviewed-on: https://go-review.googlesource.com/30470
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates #16360

Change-Id: I0e0afe7a89f2ebcb3e5bbc345f77a605d3afc398
Reviewed-on: https://go-review.googlesource.com/30103Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The UnmarshalTypeError has two new fields Struct and Field,
used when constructing the error message.

Fixes #6716.

Change-Id: I67da171480a9491960b3ae81893770644180f848
Reviewed-on: https://go-review.googlesource.com/18692
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #17224.

Some systems have more than just "lo" in a fresh network namespace, due
to IPv6. Instead of testing for exactly 3 lines of output (implying 1
interface), just test to make sure that the unshare call resulted in
fewer interfaces than before. This should still verify that unshare did
something.

Change-Id: Iaf84c2b0e673fc207059d62e2f4dd7583a753419
Reviewed-on: https://go-review.googlesource.com/30372Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Jessica Frazelle <me@jessfraz.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change float32/float64 formatting to use non-exponential form
for a slightly wider range, to more closely match ES6 JSON.stringify
and other JSON generators.

Most notably:

	1e20 now formats as 100000000000000000000 (previously 1e+20)
	1e-6 now formats as 0.000001 (previously 1e-06)
	1e-7 now formats as 1e-7 (previously 1e-07)

This also brings the int64 and float64 formatting in line with each other,
for all shared representable values. For example both int64(1234567)
and float64(1234567) now format as "1234567", where before the
float64 formatted as "1.234567e+06".

The only variation now compared to ES6 JSON.stringify is that
Go continues to encode negative zero as "-0", not "0", so that
the value continues to be preserved during JSON round trips.

Fixes #6384.
Fixes #14135.

Change-Id: Ib0e0e009cd9181d75edc0424a28fe776bcc5bbf8
Reviewed-on: https://go-review.googlesource.com/30371Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

These are conditional branches that takes a register instead of
flags as control value.

Reduce binary size by 0.7%, text size by 2.4% (cmd/go as an
exmaple).

Change-Id: I0020cfde745f9eab680b8b949ad28c87fe183afd
Reviewed-on: https://go-review.googlesource.com/30030Reviewed-by: David Chase <drchase@google.com>