<feed xmlns='http://www.w3.org/2005/Atom'>
<title>delta/go-git.git/src/runtime/testdata/testprog, branch dev.cmdgo</title>
<subtitle>github.com: golang/go
</subtitle>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/'/>
<entry>
<title>runtime: don't crash on nil pointers in checkptrAlignment</title>
<updated>2021-07-28T03:27:13+00:00</updated>
<author>
<name>Matthew Dempsky</name>
<email>mdempsky@google.com</email>
</author>
<published>2021-07-28T01:30:38+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=b39e0f461c099abf98f5a8c81d58d32d9a765a03'/>
<id>b39e0f461c099abf98f5a8c81d58d32d9a765a03</id>
<content type='text'>
Ironically, checkptrAlignment had a latent case of bad pointer
arithmetic: if ptr is nil, then `add(ptr, size-1)` might produce an
illegal pointer value.

The fix is to simply check for nil at the top of checkptrAlignment,
and short-circuit if so.

This CL also adds a more explicit bounds check in checkptrStraddles,
rather than relying on `add(ptr, size-1)` to wrap around. I don't
think this is necessary today, but it seems prudent to be careful.

Fixes #47430.

Change-Id: I5c50b2f7f41415dbebbd803e1b8e7766ca95e1fd
Reviewed-on: https://go-review.googlesource.com/c/go/+/338029
Trust: Matthew Dempsky &lt;mdempsky@google.com&gt;
Run-TryBot: Matthew Dempsky &lt;mdempsky@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Ironically, checkptrAlignment had a latent case of bad pointer
arithmetic: if ptr is nil, then `add(ptr, size-1)` might produce an
illegal pointer value.

The fix is to simply check for nil at the top of checkptrAlignment,
and short-circuit if so.

This CL also adds a more explicit bounds check in checkptrStraddles,
rather than relying on `add(ptr, size-1)` to wrap around. I don't
think this is necessary today, but it seems prudent to be careful.

Fixes #47430.

Change-Id: I5c50b2f7f41415dbebbd803e1b8e7766ca95e1fd
Reviewed-on: https://go-review.googlesource.com/c/go/+/338029
Trust: Matthew Dempsky &lt;mdempsky@google.com&gt;
Run-TryBot: Matthew Dempsky &lt;mdempsky@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cmd/compile,runtime: change unsafe.Slice((*T)(nil), 0) to return []T(nil)</title>
<updated>2021-06-28T23:31:13+00:00</updated>
<author>
<name>Matthew Dempsky</name>
<email>mdempsky@google.com</email>
</author>
<published>2021-06-25T18:07:28+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=4bb0847b088eb3eb6122a18a87e1ca7756281dcc'/>
<id>4bb0847b088eb3eb6122a18a87e1ca7756281dcc</id>
<content type='text'>
This CL removes the unconditional OCHECKNIL check added in
walkUnsafeSlice by instead passing it as a pointer to
runtime.unsafeslice, and hiding the check behind a `len == 0` check.

While here, this CL also implements checkptr functionality for
unsafe.Slice and disallows use of unsafe.Slice with //go:notinheap
types.

Updates #46742.

Change-Id: I743a445ac124304a4d7322a7fe089c4a21b9a655
Reviewed-on: https://go-review.googlesource.com/c/go/+/331070
Run-TryBot: Matthew Dempsky &lt;mdempsky@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Trust: Matthew Dempsky &lt;mdempsky@google.com&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This CL removes the unconditional OCHECKNIL check added in
walkUnsafeSlice by instead passing it as a pointer to
runtime.unsafeslice, and hiding the check behind a `len == 0` check.

While here, this CL also implements checkptr functionality for
unsafe.Slice and disallows use of unsafe.Slice with //go:notinheap
types.

Updates #46742.

Change-Id: I743a445ac124304a4d7322a7fe089c4a21b9a655
Reviewed-on: https://go-review.googlesource.com/c/go/+/331070
Run-TryBot: Matthew Dempsky &lt;mdempsky@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Trust: Matthew Dempsky &lt;mdempsky@google.com&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>runtime: don't run TestCrashDumpsAllThreads in parallel</title>
<updated>2021-04-22T00:34:25+00:00</updated>
<author>
<name>Ian Lance Taylor</name>
<email>iant@golang.org</email>
</author>
<published>2021-04-21T23:44:59+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=02a8e836616cb8eb6d776514c6239095b1328fd2'/>
<id>02a8e836616cb8eb6d776514c6239095b1328fd2</id>
<content type='text'>
It sometimes seems to time out on slow systems, perhaps due to
being run at the same time as a lot of other work.

Also move the code to testdata/testprog, so that we don't have to
build it separately.

I hope that this
Fixes #35356

Change-Id: I875b858fa23836513ae14d3116461e22fffd5352
Reviewed-on: https://go-review.googlesource.com/c/go/+/312510
Trust: Ian Lance Taylor &lt;iant@golang.org&gt;
Run-TryBot: Ian Lance Taylor &lt;iant@golang.org&gt;
Reviewed-by: Cherry Zhang &lt;cherryyz@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It sometimes seems to time out on slow systems, perhaps due to
being run at the same time as a lot of other work.

Also move the code to testdata/testprog, so that we don't have to
build it separately.

I hope that this
Fixes #35356

Change-Id: I875b858fa23836513ae14d3116461e22fffd5352
Reviewed-on: https://go-review.googlesource.com/c/go/+/312510
Trust: Ian Lance Taylor &lt;iant@golang.org&gt;
Run-TryBot: Ian Lance Taylor &lt;iant@golang.org&gt;
Reviewed-by: Cherry Zhang &lt;cherryyz@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>runtime: make sure to remove open-coded defer entries in all cases after a recover</title>
<updated>2021-01-27T20:44:24+00:00</updated>
<author>
<name>Dan Scales</name>
<email>danscales@google.com</email>
</author>
<published>2021-01-26T01:51:03+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=a5a5e2c968eb14335f4e46606d8edfbdbdcea728'/>
<id>a5a5e2c968eb14335f4e46606d8edfbdbdcea728</id>
<content type='text'>
We add entries to the defer list at panic/goexit time on-the-fly for
frames with open-coded defers. We do this so that we can correctly
process open-coded defers and non-open-coded defers in the correct order
during panics/goexits. But we need to remove entries for open-coded
defers from the defer list when there is a recover, since those entries
may never get removed otherwise and will get stale, since their
corresponding defers may now be processed normally (inline).

This bug here is that we were only removing higher-up stale entries
during a recover if all defers in the current frame were done. But we
could have more defers in the current frame (as the new test case
shows). In this case, we need to leave the current defer entry around
for use by deferreturn, but still remove any stale entries further along
the chain.

For bug 43921, simple change that we should abort the removal loop for
any defer entry that is started (i.e. in process by a still
not-recovered outer panic), even if it is not an open-coded defer.

This change does not fix bug 43920, which looks to be a more complex fix.

Fixes #43882
Fixes #43921

Change-Id: Ie05b2fa26973aa26b25c8899a2abc916090ee4f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/286712
Run-TryBot: Dan Scales &lt;danscales@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Matthew Dempsky &lt;mdempsky@google.com&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
Trust: Dan Scales &lt;danscales@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We add entries to the defer list at panic/goexit time on-the-fly for
frames with open-coded defers. We do this so that we can correctly
process open-coded defers and non-open-coded defers in the correct order
during panics/goexits. But we need to remove entries for open-coded
defers from the defer list when there is a recover, since those entries
may never get removed otherwise and will get stale, since their
corresponding defers may now be processed normally (inline).

This bug here is that we were only removing higher-up stale entries
during a recover if all defers in the current frame were done. But we
could have more defers in the current frame (as the new test case
shows). In this case, we need to leave the current defer entry around
for use by deferreturn, but still remove any stale entries further along
the chain.

For bug 43921, simple change that we should abort the removal loop for
any defer entry that is started (i.e. in process by a still
not-recovered outer panic), even if it is not an open-coded defer.

This change does not fix bug 43920, which looks to be a more complex fix.

Fixes #43882
Fixes #43921

Change-Id: Ie05b2fa26973aa26b25c8899a2abc916090ee4f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/286712
Run-TryBot: Dan Scales &lt;danscales@google.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Matthew Dempsky &lt;mdempsky@google.com&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
Trust: Dan Scales &lt;danscales@google.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>all: update to use os.ReadFile, os.WriteFile, os.CreateTemp, os.MkdirTemp</title>
<updated>2020-12-09T19:12:23+00:00</updated>
<author>
<name>Russ Cox</name>
<email>rsc@golang.org</email>
</author>
<published>2020-10-29T18:17:47+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=4f1b0a44cb46f3df28f5ef82e5769ebeac1bc493'/>
<id>4f1b0a44cb46f3df28f5ef82e5769ebeac1bc493</id>
<content type='text'>
As part of #42026, these helpers from io/ioutil were moved to os.
(ioutil.TempFile and TempDir became os.CreateTemp and MkdirTemp.)

Update the Go tree to use the preferred names.

As usual, code compiled with the Go 1.4 bootstrap toolchain
and code vendored from other sources is excluded.

ReadDir changes are in a separate CL, because they are not a
simple search and replace.

For #42026.

Change-Id: If318df0216d57e95ea0c4093b89f65e5b0ababb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/266365
Trust: Russ Cox &lt;rsc@golang.org&gt;
Run-TryBot: Russ Cox &lt;rsc@golang.org&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Ian Lance Taylor &lt;iant@golang.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As part of #42026, these helpers from io/ioutil were moved to os.
(ioutil.TempFile and TempDir became os.CreateTemp and MkdirTemp.)

Update the Go tree to use the preferred names.

As usual, code compiled with the Go 1.4 bootstrap toolchain
and code vendored from other sources is excluded.

ReadDir changes are in a separate CL, because they are not a
simple search and replace.

For #42026.

Change-Id: If318df0216d57e95ea0c4093b89f65e5b0ababb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/266365
Trust: Russ Cox &lt;rsc@golang.org&gt;
Run-TryBot: Russ Cox &lt;rsc@golang.org&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Ian Lance Taylor &lt;iant@golang.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "runtime: make stack traces of endless recursion print only top and bottom 50"</title>
<updated>2020-11-09T21:03:36+00:00</updated>
<author>
<name>Emmanuel Odeke</name>
<email>emmanuel@orijtech.com</email>
</author>
<published>2020-11-09T20:31:58+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=d4957122ee8a45aa73b0e8700d3a41c0ee9f4442'/>
<id>d4957122ee8a45aa73b0e8700d3a41c0ee9f4442</id>
<content type='text'>
This reverts commit 3a81338622eb5c8b94f11001855e2a68a9e36bed.

Reason for revert: Some edge cases not properly covered due to changes within runtime traceback generation since 2017, that need to be examined. This change landed very late in the Go1.16 cycle.

Change-Id: I8cf6f46ea0ef6161d878e79943e6c7cdac94bccf
Reviewed-on: https://go-review.googlesource.com/c/go/+/268577
Trust: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
Run-TryBot: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This reverts commit 3a81338622eb5c8b94f11001855e2a68a9e36bed.

Reason for revert: Some edge cases not properly covered due to changes within runtime traceback generation since 2017, that need to be examined. This change landed very late in the Go1.16 cycle.

Change-Id: I8cf6f46ea0ef6161d878e79943e6c7cdac94bccf
Reviewed-on: https://go-review.googlesource.com/c/go/+/268577
Trust: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
Run-TryBot: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>runtime: make stack traces of endless recursion print only top and bottom 50</title>
<updated>2020-11-06T23:53:49+00:00</updated>
<author>
<name>Emmanuel T Odeke</name>
<email>emmanuel@orijtech.com</email>
</author>
<published>2017-02-18T10:03:32+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=3a81338622eb5c8b94f11001855e2a68a9e36bed'/>
<id>3a81338622eb5c8b94f11001855e2a68a9e36bed</id>
<content type='text'>
This CL makes it so that instead of printing massive stack traces during
endless recursion, which spams users and aren't useful, it now prints out
the top and bottom 50 frames. If the number of frames &lt;= 100
(_TracebackMaxFrames), we'll just print all the frames out.

Modified gentraceback to return counts of:
* ntotalframes
* nregularframes
which allows us to get accurate counts of the various kinds of frames.

While here, also fixed a bug that resulted from CL 37222, in which we
no longer accounted for decrementing requested frame skips, and assumed
that when printing, that skip would always be 0. The fix is instead to add
precondition that we'll only print if skip &lt;= 0, but also decrement skip
as we iterate.

Fixes #7181.
Fixes #24628.

Change-Id: Ie31ec6413fdfbe43827b254fef7d99ea26a5277f
Reviewed-on: https://go-review.googlesource.com/c/go/+/37222
Run-TryBot: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
Trust: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This CL makes it so that instead of printing massive stack traces during
endless recursion, which spams users and aren't useful, it now prints out
the top and bottom 50 frames. If the number of frames &lt;= 100
(_TracebackMaxFrames), we'll just print all the frames out.

Modified gentraceback to return counts of:
* ntotalframes
* nregularframes
which allows us to get accurate counts of the various kinds of frames.

While here, also fixed a bug that resulted from CL 37222, in which we
no longer accounted for decrementing requested frame skips, and assumed
that when printing, that skip would always be 0. The fix is instead to add
precondition that we'll only print if skip &lt;= 0, but also decrement skip
as we iterate.

Fixes #7181.
Fixes #24628.

Change-Id: Ie31ec6413fdfbe43827b254fef7d99ea26a5277f
Reviewed-on: https://go-review.googlesource.com/c/go/+/37222
Run-TryBot: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
TryBot-Result: Go Bot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
Trust: Emmanuel Odeke &lt;emmanuel@orijtech.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cmd/compile: fix checkptr handling of &amp;^</title>
<updated>2020-08-20T17:48:29+00:00</updated>
<author>
<name>Matthew Dempsky</name>
<email>mdempsky@google.com</email>
</author>
<published>2020-08-20T04:39:12+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=e94544cf012535da6b3c9e735bc4026e2db1c99c'/>
<id>e94544cf012535da6b3c9e735bc4026e2db1c99c</id>
<content type='text'>
checkptr has code to recognize &amp;^ expressions, but it didn't take into
account that "p &amp;^ x" gets rewritten to "p &amp; ^x" during walk, which
resulted in false positive diagnostics.

This CL changes walkexpr to mark OANDNOT expressions with Implicit
when they're rewritten to OAND, so that walkCheckPtrArithmetic can
still recognize them later.

It would be slightly more idiomatic to instead mark the OBITNOT
expression as Implicit (as it's a compiler-generated Node), but the
OBITNOT expression might get constant folded. It's not worth the extra
complexity/subtlety of relying on n.Right.Orig, so we set Implicit on
the OAND node instead.

To atone for this transgression, I add documentation for nodeImplicit.

Fixes #40917.

Change-Id: I386304171ad299c530e151e5924f179e9a5fd5b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/249477
Run-TryBot: Matthew Dempsky &lt;mdempsky@google.com&gt;
TryBot-Result: Gobot Gobot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
Reviewed-by: Cuong Manh Le &lt;cuong.manhle.vn@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
checkptr has code to recognize &amp;^ expressions, but it didn't take into
account that "p &amp;^ x" gets rewritten to "p &amp; ^x" during walk, which
resulted in false positive diagnostics.

This CL changes walkexpr to mark OANDNOT expressions with Implicit
when they're rewritten to OAND, so that walkCheckPtrArithmetic can
still recognize them later.

It would be slightly more idiomatic to instead mark the OBITNOT
expression as Implicit (as it's a compiler-generated Node), but the
OBITNOT expression might get constant folded. It's not worth the extra
complexity/subtlety of relying on n.Right.Orig, so we set Implicit on
the OAND node instead.

To atone for this transgression, I add documentation for nodeImplicit.

Fixes #40917.

Change-Id: I386304171ad299c530e151e5924f179e9a5fd5b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/249477
Run-TryBot: Matthew Dempsky &lt;mdempsky@google.com&gt;
TryBot-Result: Gobot Gobot &lt;gobot@golang.org&gt;
Reviewed-by: Keith Randall &lt;khr@golang.org&gt;
Reviewed-by: Cuong Manh Le &lt;cuong.manhle.vn@gmail.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>runtime, time: gofmt</title>
<updated>2020-05-26T22:06:26+00:00</updated>
<author>
<name>Tobias Klauser</name>
<email>tklauser@distanz.ch</email>
</author>
<published>2020-05-26T13:58:13+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=4abec2a48070da6ca9b8cf53888ad993e0ee82ef'/>
<id>4abec2a48070da6ca9b8cf53888ad993e0ee82ef</id>
<content type='text'>
Change-Id: Ib36a5f239db5af497aae122eba049c15d0d4c4a8
Reviewed-on: https://go-review.googlesource.com/c/go/+/235139
Run-TryBot: Tobias Klauser &lt;tobias.klauser@gmail.com&gt;
TryBot-Result: Gobot Gobot &lt;gobot@golang.org&gt;
Reviewed-by: Ian Lance Taylor &lt;iant@golang.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Change-Id: Ib36a5f239db5af497aae122eba049c15d0d4c4a8
Reviewed-on: https://go-review.googlesource.com/c/go/+/235139
Run-TryBot: Tobias Klauser &lt;tobias.klauser@gmail.com&gt;
TryBot-Result: Gobot Gobot &lt;gobot@golang.org&gt;
Reviewed-by: Ian Lance Taylor &lt;iant@golang.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>runtime: detect and report zombie slots during sweeping</title>
<updated>2020-05-21T21:36:40+00:00</updated>
<author>
<name>Austin Clements</name>
<email>austin@google.com</email>
</author>
<published>2020-05-14T20:55:39+00:00</published>
<link rel='alternate' type='text/html' href='http://git.baserock.org/cgit/delta/go-git.git/commit/?id=ea2de3346ff8714c9fae95c2a3d686ec07d47ca8'/>
<id>ea2de3346ff8714c9fae95c2a3d686ec07d47ca8</id>
<content type='text'>
A zombie slot is a slot that is marked, but isn't allocated. This can
indicate a bug in the GC, or a bad use of unsafe.Pointer. Currently,
the sweeper has best-effort detection for zombie slots: if there are
more marked slots than allocated slots, then there must have been a
zombie slot. However, this is imprecise since it only compares totals
and it reports almost no information that may be helpful to debug the
issue.

Add a precise check that compares the mark and allocation bitmaps and
reports detailed information if it detects a zombie slot.

No appreciable effect on performance as measured by the sweet
benchmarks:

name                                old time/op  new time/op  delta
BiogoIgor                            15.8s ± 2%   15.8s ± 2%    ~     (p=0.421 n=24+25)
BiogoKrishna                         15.6s ± 2%   15.8s ± 5%    ~     (p=0.082 n=22+23)
BleveIndexBatch100                   4.90s ± 3%   4.88s ± 2%    ~     (p=0.627 n=25+24)
CompileTemplate                      204ms ± 1%   205ms ± 0%  +0.22%  (p=0.010 n=24+23)
CompileUnicode                      77.8ms ± 2%  78.0ms ± 1%    ~     (p=0.236 n=25+24)
CompileGoTypes                       729ms ± 0%   731ms ± 0%  +0.26%  (p=0.000 n=24+24)
CompileCompiler                      3.52s ± 0%   3.52s ± 1%    ~     (p=0.152 n=25+25)
CompileSSA                           8.06s ± 1%   8.05s ± 0%    ~     (p=0.192 n=25+24)
CompileFlate                         132ms ± 1%   132ms ± 1%    ~     (p=0.373 n=24+24)
CompileGoParser                      163ms ± 1%   164ms ± 1%  +0.32%  (p=0.003 n=24+25)
CompileReflect                       453ms ± 1%   455ms ± 1%  +0.39%  (p=0.000 n=22+22)
CompileTar                           181ms ± 1%   181ms ± 1%  +0.20%  (p=0.029 n=24+21)
CompileXML                           244ms ± 1%   244ms ± 1%    ~     (p=0.065 n=24+24)
CompileStdCmd                        15.8s ± 2%   15.7s ± 2%    ~     (p=0.059 n=23+24)
FoglemanFauxGLRenderRotateBoat       13.4s ±11%   12.8s ± 0%    ~     (p=0.377 n=25+24)
FoglemanPathTraceRenderGopherIter1   18.6s ± 0%   18.6s ± 0%    ~     (p=0.696 n=23+24)
GopherLuaKNucleotide                 28.7s ± 4%   28.6s ± 5%    ~     (p=0.700 n=25+25)
MarkdownRenderXHTML                  250ms ± 1%   248ms ± 1%  -1.01%  (p=0.000 n=24+24)
[Geo mean]                           1.60s        1.60s       -0.11%

(https://perf.golang.org/search?q=upload:20200517.6)

For #38702.

Change-Id: I8af1fefd5fbf7b9cb665b98f9c4b73d1d08eea81
Reviewed-on: https://go-review.googlesource.com/c/go/+/234100
Run-TryBot: Austin Clements &lt;austin@google.com&gt;
TryBot-Result: Gobot Gobot &lt;gobot@golang.org&gt;
Reviewed-by: Cherry Zhang &lt;cherryyz@google.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A zombie slot is a slot that is marked, but isn't allocated. This can
indicate a bug in the GC, or a bad use of unsafe.Pointer. Currently,
the sweeper has best-effort detection for zombie slots: if there are
more marked slots than allocated slots, then there must have been a
zombie slot. However, this is imprecise since it only compares totals
and it reports almost no information that may be helpful to debug the
issue.

Add a precise check that compares the mark and allocation bitmaps and
reports detailed information if it detects a zombie slot.

No appreciable effect on performance as measured by the sweet
benchmarks:

name                                old time/op  new time/op  delta
BiogoIgor                            15.8s ± 2%   15.8s ± 2%    ~     (p=0.421 n=24+25)
BiogoKrishna                         15.6s ± 2%   15.8s ± 5%    ~     (p=0.082 n=22+23)
BleveIndexBatch100                   4.90s ± 3%   4.88s ± 2%    ~     (p=0.627 n=25+24)
CompileTemplate                      204ms ± 1%   205ms ± 0%  +0.22%  (p=0.010 n=24+23)
CompileUnicode                      77.8ms ± 2%  78.0ms ± 1%    ~     (p=0.236 n=25+24)
CompileGoTypes                       729ms ± 0%   731ms ± 0%  +0.26%  (p=0.000 n=24+24)
CompileCompiler                      3.52s ± 0%   3.52s ± 1%    ~     (p=0.152 n=25+25)
CompileSSA                           8.06s ± 1%   8.05s ± 0%    ~     (p=0.192 n=25+24)
CompileFlate                         132ms ± 1%   132ms ± 1%    ~     (p=0.373 n=24+24)
CompileGoParser                      163ms ± 1%   164ms ± 1%  +0.32%  (p=0.003 n=24+25)
CompileReflect                       453ms ± 1%   455ms ± 1%  +0.39%  (p=0.000 n=22+22)
CompileTar                           181ms ± 1%   181ms ± 1%  +0.20%  (p=0.029 n=24+21)
CompileXML                           244ms ± 1%   244ms ± 1%    ~     (p=0.065 n=24+24)
CompileStdCmd                        15.8s ± 2%   15.7s ± 2%    ~     (p=0.059 n=23+24)
FoglemanFauxGLRenderRotateBoat       13.4s ±11%   12.8s ± 0%    ~     (p=0.377 n=25+24)
FoglemanPathTraceRenderGopherIter1   18.6s ± 0%   18.6s ± 0%    ~     (p=0.696 n=23+24)
GopherLuaKNucleotide                 28.7s ± 4%   28.6s ± 5%    ~     (p=0.700 n=25+25)
MarkdownRenderXHTML                  250ms ± 1%   248ms ± 1%  -1.01%  (p=0.000 n=24+24)
[Geo mean]                           1.60s        1.60s       -0.11%

(https://perf.golang.org/search?q=upload:20200517.6)

For #38702.

Change-Id: I8af1fefd5fbf7b9cb665b98f9c4b73d1d08eea81
Reviewed-on: https://go-review.googlesource.com/c/go/+/234100
Run-TryBot: Austin Clements &lt;austin@google.com&gt;
TryBot-Result: Gobot Gobot &lt;gobot@golang.org&gt;
Reviewed-by: Cherry Zhang &lt;cherryyz@google.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
