Add a new lowering rule to match and replace such instances
with the MADDLD instruction available on power9 where
possible.
Likewise, this plumbs in a new ppc64 ssa opcode to house
the newly generated MADDLD instructions.
When testing ed25519, this reduced binary size by 936B.
Similarly, MADDLD combination occcurs in a few other less
obvious cases such as division by constant.
Testing of golang.org/x/crypto/ed25519 shows non-trivial
speedup during keygeneration:
name old time/op new time/op delta
KeyGeneration 65.2µs ± 0% 63.1µs ± 0% -3.19%
Signing 64.3µs ± 0% 64.4µs ± 0% +0.16%
Verification 147µs ± 0% 147µs ± 0% +0.11%
Similarly, this test binary has shrunk by 66488B.
Change-Id: I077aeda7943119b41f07e4e62e44a648f16e4ad0
Reviewed-on: https://go-review.googlesource.com/c/go/+/248723
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>
Remove some unnecessary code. Most significantly, we can skip testing
"if ch == nil { block() }", because this is already the semantics
implied by normal send/receive operations.
Updates #40410.
Change-Id: I4acd33383cc876719fc3b998d85244d4ac1ff9d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/245126
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Currently, we include a "kind" field on scase to distinguish the three
kinds of cases in a select statement: sends, receives, and defaults.
This commit removes by kind field by instead arranging for the
compiler to always place sends before receives, and to provide their
counts separately. It also passes an explicit "block bool" parameter
to avoid needing to include a default case in the array.
It's safe to shuffle cases like this because the runtime will
randomize the order they're polled in anyway.
Fixes#40410.
Change-Id: Iaeaed4cf7bddd576d78f2c863bd91a03a5c82df2
Reviewed-on: https://go-review.googlesource.com/c/go/+/245125
Reviewed-by: Keith Randall <khr@golang.org>
Per-case PCs are only needed for race detector builds, so this allows
skipping allocating stack space for them for non-race builds.
It's possible to arrange the PCs and order arrays consecutively in
memory so that we could just reuse the order0 pointer to identify
both. However, there's more risk of that silently going wrong, so this
commit passes them as separate arguments for now. We can revisit this
in the future.
Updates #40410.
Change-Id: I8468bc25749e559891cb0cb007d1cc4a40fdd0f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/245124
Reviewed-by: Keith Randall <khr@golang.org>
Currently, selectgo does an initial pass over the cases array to look
for entries with nil channels, so they can be easily recognized and
skipped later on. But this still involves actually visiting the cases.
This commit changes selectgo to omit cases with nil channels when
constructing pollorder, so that they'll be skipped over entirely later
on. It also checks for caseDefault up front, which will facilitate
changing it to use a "block bool" parameter instead.
Updates #40410.
Change-Id: Icaebcb8f08df03cc33b6d8087616fb5585f7fedd
Reviewed-on: https://go-review.googlesource.com/c/go/+/245123
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
selectgo will report at most one block event, so there's no need to
keep a releasetime for every select case. It suffices to simply track
the releasetime of the case responsible for the wakeup.
Updates #40410.
Change-Id: I72679cd43dde80d7e6dbab21a78952a4372d1e79
Reviewed-on: https://go-review.googlesource.com/c/go/+/245122
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The current wakeup protocol for channel communications is that the
second goroutine sets gp.param to the sudog when a value is
successfully communicated over the channel, and to nil when the wakeup
is due to closing the channel.
Setting nil to indicate channel closure works okay for chansend and
chanrecv, because they're only communicating with one channel, so they
know it must be the channel that was closed. However, it means
selectgo has to re-poll all of the channels to figure out which one
was closed.
This commit adds a "success" field to sudog, and changes the wakeup
protocol to always set gp.param to sg, and to use sg.success to
indicate successful communication vs channel closure.
While here, this also reorganizes the chansend code slightly so that
the sudog is still released to the pool if the send blocks and then is
awoken because the channel closed.
Updates #40410.
Change-Id: I6cd9a20ebf9febe370a15af1b8afe24c5539efc6
Reviewed-on: https://go-review.googlesource.com/c/go/+/245019
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Replace strings.Split by strings.IndexByte and explicit
slicing to avoid the allocation of the return slice
of strings.Split.
name old time/op new time/op delta
Marshal 43.3µs ± 1% 36.7µs ± 1% -15.23% (p=0.000 n=9+9)
name old alloc/op new alloc/op delta
Marshal 10.7kB ± 0% 9.2kB ± 0% -13.96% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
Marshal 444 ± 0% 366 ± 0% -17.57% (p=0.000 n=10+10)
Change-Id: I9e727defa23f7e5fc684f246de0136fe28cf8d25
Reviewed-on: https://go-review.googlesource.com/c/go/+/231738
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
We could instead fix cmd/test2json to treat PAUSE lines as *not*
changing the active test name, but that seems like it would be more
confusing to humans, and also wouldn't fix tools that parse output
using existing builds of cmd/test2json.
Fixes#40657
Change-Id: I937611778f5b1e7dd1d6e9f44424d7e725a589ed
Reviewed-on: https://go-review.googlesource.com/c/go/+/248727
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Jean de Klerk <deklerk@google.com>
There were two places where the -short flag was added in order to
speed up tests when run in short mode, in CL 178399 and CL 177417.
It appears viable to re-use the GO_TEST_SHORT value so that -short
flag is not used when the tests are executed on a longtest builder,
where it is not a goal to skip slow tests for improved performance.
Do so, in order to make the testing configurations simpler and more
predictable.
Factor out the flag name out of the string returned by short, so that
it can be used in context of 'go test' which can accept a -short flag,
and a test binary which requires the use of a longer -test.short flag.
For #39054.
For #29252.
Change-Id: I52dfbef73cc8307735c52e2ebaa609305fb05933
Reviewed-on: https://go-review.googlesource.com/c/go/+/233898
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
When external linking, for large binaries, the external linker
may insert a trampoline for the write barrier call, which looks
0000000005a98cc8 <__long_branch_runtime.gcWriteBarrier>:
5a98cc8: 86 01 82 3d addis r12,r2,390
5a98ccc: d8 bd 8c e9 ld r12,-16936(r12)
5a98cd0: a6 03 89 7d mtctr r12
5a98cd4: 20 04 80 4e bctr
It clobbers R12 (and CTR, which is never live across a call).
As at compile time we don't know whether the binary is big and
what link mode will be used, I think we need to mark R12 as
clobbered for write barrier call. For extra safety (future-proof)
we mark caller-saved register that cannot be used for function
arguments, which includes R11, as potentially clobbered as well.
Fixes#40851.
Change-Id: Iedd901c5072f1127cc59b0a48cfeb4aaec81b519
Reviewed-on: https://go-review.googlesource.com/c/go/+/248917
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This reverts the following changes:
• cmd/go: add tracing for querying and downloading from the proxy
CL 242786, commit 1a35583418
• cmd/go: do context propagation for tracing downloads
CL 248327, commit c0cf190d22
• cmd/go/internal: remove some users of par.Work
CL 248326, commit f30044a03b
Reason for revert: broke linux 386 and amd64 longtest builders.
The problem started with CL 248326, but CL 248327 and CL 242786
are reverted as well due to conflicts.
Updates #38714.
Fixes#40861.
Change-Id: I68496b4e5a27e47a42183553c3a645b288edac83
Reviewed-on: https://go-review.googlesource.com/c/go/+/249017
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Some of the existing optimizations aren't triggered because they
are handled by the generic rules so this CL removes them. Also
some constraints were copied without much thought from the amd64
rules and they don't make sense on s390x, so we remove those
constraints.
Finally, add a 'multiply by the sum of two powers of two'
optimization. This makes sense on s390x as shifts are low latency
and can also sometimes be optimized further (especially if we add
support for RISBG instructions).
name old time/op new time/op delta
IntMulByConst/3-8 1.70ns ±11% 1.10ns ± 5% -35.26% (p=0.000 n=10+10)
IntMulByConst/5-8 1.64ns ± 7% 1.10ns ± 4% -32.94% (p=0.000 n=10+9)
IntMulByConst/12-8 1.65ns ± 6% 1.20ns ± 4% -27.16% (p=0.000 n=10+9)
IntMulByConst/120-8 1.66ns ± 4% 1.22ns ±13% -26.43% (p=0.000 n=10+10)
IntMulByConst/-120-8 1.65ns ± 7% 1.19ns ± 4% -28.06% (p=0.000 n=9+10)
IntMulByConst/65537-8 0.86ns ± 9% 1.12ns ±12% +30.41% (p=0.000 n=10+10)
IntMulByConst/65538-8 1.65ns ± 5% 1.23ns ± 5% -25.11% (p=0.000 n=10+10)
Change-Id: Ib196e6bff1e97febfd266134d0a2b2a62897989f
Reviewed-on: https://go-review.googlesource.com/c/go/+/248937
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
startupRandomData is only used in sysauxv and getRandomData on linux,
thus move it closer to where it is used. Also adjust its godoc comment.
Change-Id: Ice51d579ec33436adbfdf247caf4ba00bae865e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/248761
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
No need to check operr before returning.
Change-Id: I64b849f7c102de01180823e3f0123d438ce7608a
Reviewed-on: https://go-review.googlesource.com/c/go/+/232797
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
A typo in the conversion code caused comparisons of SSA types to
report CMPeq when they were not in fact equal.
Fixes#40837
Change-Id: I0627eee51d524a585908b34a4590bc533c8415fc
Reviewed-on: https://go-review.googlesource.com/c/go/+/248781
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Change-Id: Ia3fb30ac9add39c803f11f69d967c6604fdeacf8
Reviewed-on: https://go-review.googlesource.com/c/go/+/233217
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
For an unsigned integer, it's useful to convert its order test with 0/1
to its equality test with 0. We can save a comparison instruction that
followed by a conditional branch on arm64 since it supports
compare-with-zero-and-branch instructions. For example,
if x > 0 { ... } else { ... }
the original version:
CMP $0, R0
BLS 9
the optimized version:
CBZ R0, 8
Updates #21439
Change-Id: Id1de6f865f6aa72c5d45b29f7894818857288425
Reviewed-on: https://go-review.googlesource.com/c/go/+/246857
Reviewed-by: Keith Randall <khr@golang.org>
Corrects ErrReader's signature to what was accepted in the approved
proposal, and also removes an exported ErrIO which wasn't part of
the proposal and is unnecessary.
The new signature allows users to customize their own errors.
While here, started examples, with ErrReader leading the way.
Updates #38781
Change-Id: Ia7f84721f11061343cfef8b1adc2b7b69bc3f43c
Reviewed-on: https://go-review.googlesource.com/c/go/+/248898
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We aren't using it for anything. The visited map will terminate
any recursion for us.
Change-Id: I36e6bd8e34952123c2ed46323067e42928ec7168
Reviewed-on: https://go-review.googlesource.com/c/go/+/238759
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
If the AND has other uses, we end up saving an argument to the AND
in another register, so we can use it for the TEST. No point in doing that.
Change-Id: I73444a6aeddd6f55e2328ce04d77c3e6cf4a83e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/241280
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Just like SIGILL, it might be useful to see what the instruction
that generated the SIGFPE is.
Update #39816
Change-Id: I8b2ff692998f0b770289339537dceab96b09d1ee
Reviewed-on: https://go-review.googlesource.com/c/go/+/239999
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
I noticed that there is a Todo comment here. This variable is only used for filename when dump a function's ssa passes result in details. It is no problem to print a function alone, but may be edited by not only one goroutine if dump multiple functions at the same time. Although it looks only dump one function's ssa passes now. As far as I am concerned this variable can be a member variable of the struct Func. I'm not sure if this change is necessary. Looking forward to your advices, thank you very much.
Change-Id: I35dd7247889e0cc7f19c0b400b597206592dee75
Reviewed-on: https://go-review.googlesource.com/c/go/+/244918
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Use CBZ to replace the comparison and jump to the zero instruction in the arm64 assembly file.
Change-Id: Ie16fb52e27b4d327343e119ebc0f0ca756437bc4
Reviewed-on: https://go-review.googlesource.com/c/go/+/237477
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Use CBZ to replace the comparison and branch of arm64 and the zero instruction in the assembly file.
Change-Id: Id6c03e9af13aadafc3ad3953f82d2ffa29c12926
Reviewed-on: https://go-review.googlesource.com/c/go/+/237497
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This change deletes the old mcentral implementation from the code base
and the newMCentralImpl feature flag along with it.
Updates #37487.
Change-Id: Ibca8f722665f0865051f649ffe699cbdbfdcfcf2
Reviewed-on: https://go-review.googlesource.com/c/go/+/221184
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
This change removes the old markrootSpans implementation and deletes the
feature flag.
Updates #37487.
Change-Id: Idb5a2559abcc3be5a7da6f2ccce1a86e1d7634e3
Reviewed-on: https://go-review.googlesource.com/c/go/+/221183
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Austin Clements <austin@google.com>
There are some architecture-independent rules in #21439, since an
unsigned integer >= 0 is always true and < 0 is always false. This CL
adds these optimizations to generic rules.
Updates #21439
Change-Id: Iec7e3040b761ecb1e60908f764815fdd9bc62495
Reviewed-on: https://go-review.googlesource.com/c/go/+/246617
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This change does context propagation (and only context propagation)
necessary to add context to modfetch.Download and pkg.LoadImport.
This was done by adding context to their callers, and then
adding context to all call-sites, and then repeating adding
context to callers of those enclosing functions and their
callers until none were left. In some cases the call graph expansion
was pruned by using context.TODOs.
The next CL will add a span to Download. I kept it out of this
change to avoid making it any larger (and harder to review)
than it needs to be.
Updates #38714
Change-Id: I5bf2d599aafef67334c384dfccd5e255198c85b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/248327
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
If we are parsing a test output, and the test does not end in the
usual PASS or FAIL line (say, because it panicked), then we need the
exit status of the test binary in order to determine whether the test
passed or failed. If we don't have that status available, we shouldn't
guess arbitrarily — instead, we should omit the final "pass" or "fail"
action entirely.
(In practice, we nearly always DO have the final status, such as when
running 'go test' or 'go tool test2json some.exe'.)
Fixes#40132
Change-Id: Iae482577361a6033395fe4a05d746b980e18c3de
Reviewed-on: https://go-review.googlesource.com/c/go/+/248624
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
par.Work is used in a number of places as a parallel
work queue. This change replaces it with goroutines
and channels in a number of simpler places where it's
used.
Change-Id: I0620eda46ec7b2c0599a8b9361639af7bb73a05a
Reviewed-on: https://go-review.googlesource.com/c/go/+/248326
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This change adds context, and a span to modload.LoadBuildList and
propagates context into modload.BuildList. It's the start
of a run of CLs to add trace spans for module operations.
Updates #38714
Change-Id: I0d58dd394051526338092dc9a5ec29a9e087e4e4
Reviewed-on: https://go-review.googlesource.com/c/go/+/248325
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
These commands are build-like commands that do their own flag
processing, so the value of debug-trace isn't available until
the command starts running. Start tracing in the cmd's run
function.
Updates #38714
Change-Id: I4d633e6ee907bf09feac52c2aff3daceb9b20e12
Reviewed-on: https://go-review.googlesource.com/c/go/+/248324
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This could help make it easier to identify blocking
dependencies when examining traces. Flows can be turned
off when viewing traces to remove potential distractions.
Updates #38714
Change-Id: Ibfd3f1a1861e3cac31addb053a2fca7ee796c4d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/248322
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Action.Func is now a func(*Builder, context.Context, *Action), so that
contexts can be propagated into the action funcs. While context
is traditionally the first parameter of a function, it's the second
parameter of Action.Func's type to continue to allow for methods
on Builder to be used as functions taking a *Builder as the first
parameter. context.Context is instead the first parameter on
those functions.
Change-Id: I5f058d6a99a1e96fe2025f2e8ce30a033d12e935
Reviewed-on: https://go-review.googlesource.com/c/go/+/248321
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This change adds a trace event for each action and also
annotates each of the action execution goroutines with trace.Goroutine
so that the actions eaxecuted by each goroutine appear on different threads in
the chrome trace viewer.
Updates #38714
Change-Id: I2e58dc5606b2e3f7f87076a61e1cc6a2014255c5
Reviewed-on: https://go-review.googlesource.com/c/go/+/248320
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
trace.StartGoroutine will associate the trace information on the context
with a new chrome profiler thread id. The chrome profiler doesn't
expect multiple trace events to have the same thread id, so this
will allow us to display concurrent events on the trace.
Updates #38714
Change-Id: I888b0cce15a5a01db66366716fdd85bf86c832cd
Reviewed-on: https://go-review.googlesource.com/c/go/+/248319
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
On ARM, for a JMP/CALL relocation, the instruction bytes is
encoded in Reloc.Add (issue #19811). I really hate it, but before
it is fixed we have to follow the rule and emit the right bits
from r.Add.
Fixes#40769.
Change-Id: I862e105408d344c5cc58ca9140d2e552e4364453
Reviewed-on: https://go-review.googlesource.com/c/go/+/248399
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Than McIntosh <thanm@google.com>
cgo_import_dynamic pragma indicates a symbol is imported from a
dynamic library. Currently, the linker does not actually link
against the dynamic library, so we have to "force" it by using
//go:cgo_import_dynamic _ _ "dylib"
syntax, which links in the library unconditionally.
This CL changes it to link in the library automatically when a
symbol is imported from the library, without using the "force"
syntax. (The "force" syntax is still supported.)
Remove the unconditional imports in the runtime. Now,
Security.framework and CoreFoundation.framework are only linked
when the x509 package is imported (or otherwise specified).
Fixes#40727.
Change-Id: Ied36b1f621cdcc5dc4a8f497cdf1c554a182d0e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/248333
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
