This CL fixes the merge locals error.
The culprit is that liveness analysis wrongly mark SIMD structs fat,
hence making `StoreReg` of SIMD vectors not a varkill effect, making the
liveness range of SIMD vectors not closed correctly, further making
mergelocals merged 2 concurrently-live SIMD vectors.
Is looks like mergelocals will treat the live range as one instruction
if it's not closed: [st, st+1). Should we make it [st, +inf) instead? So
that we won't have similar errors in the future.
Also, I feel we really need to examine every "case types.TSTRUCT" or "if
t.Kind() == types.TSTRUCT" in the codebase correctly for SIMD types...
Change-Id: I2f4f4f36a890bd317d582cfa73a8f6a789382d91
Reviewed-on: https://go-review.googlesource.com/c/go/+/687775
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com>
This CL does:
1. Removes ShiftRightSignExtended, default signed vectors to shift
arithmetic, and unsigned to shift logical.
2. Add the missing Shifts which were left out by YAML error in the
generator.
This CL is generated by CL 687595.
Change-Id: I663115498adb91c82e89a8476e6748794e997cfa
Reviewed-on: https://go-review.googlesource.com/c/go/+/687596
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
[dev.simd] cmd/compile: exclude simd vars from merge local
It looks like mergelocals pass's liveness analysis does not handle simd
variables well.
The added test forces two vectors to spill in a way that does not work
with mergelocals: if the added check is removed, then `v` and `m` will
be marked merged and spilled to the same location, failing the test.
Change-Id: Ife4e4e939565d817fc24f7180cb791a5084dd191
Reviewed-on: https://go-review.googlesource.com/c/go/+/687375
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com>
Cherry Mui [Fri, 11 Jul 2025 15:41:23 +0000 (11:41 -0400)]
[dev.simd] all: merge master (88cf0c5) into dev.simd
Merge List:
+ 2025-07-11 88cf0c5d55 cmd/link: do size fixups after symbol references are loaded
+ 2025-07-10 7a38975a48 os: trivial comment fix
+ 2025-07-10 aa5de9ebb5 synctest: fix comments for time.Now() in synctests
+ 2025-07-10 63ec70d4e1 crypto/cipher: Fix comment punctuation
+ 2025-07-09 8131635e5a runtime: run TestSignalDuringExec in its own process group
+ 2025-07-09 67c1704444 crypto/tls: empty server_name conf. ext. from server
+ 2025-07-08 54c9d77630 cmd/go: disable support for multiple vcs in one module
+ 2025-07-08 fca43a8436 internal: make struct comment match struct name
+ 2025-07-08 bb917bb030 cmd/compile: document that nosplit directive is unsafe
+ 2025-07-08 a5bda585d5 cmd/compile: run fmt on ssa
+ 2025-07-07 86b5ba7310 internal/trace: only test for sync preemption if async preemption is off
+ 2025-07-07 ef46e1b164 cmd/internal/doc: fix GOROOT skew and path joining bugs
+ 2025-07-07 75b43f9a97 runtime: make traceStack testable and add a benchmark
+ 2025-07-07 20978f46fd crypto/rsa: remove another forgotten note to future self
+ 2025-07-07 33fb4819f5 cmd/compile/internal/ssa: skip EndSequence entries in TestStmtLines
+ 2025-07-07 a995269a93 sort: clarify Less doc
+ 2025-07-03 6c3b5a2798 runtime: correct vdsoSP on S390X
+ 2025-07-03 dd687c3860 hash: document that Clone may only return ErrUnsupported or a nil error
+ 2025-07-02 b325151453 cmd/cgo/internal/testsanitizers: skip asan tests when FIPS140 mode is on
+ 2025-07-02 15d9fe43d6 testing/synctest: explicitly state Run will be removed in Go 1.26
+ 2025-07-01 de646d94f7 cmd/go/internal/modindex: apply changes in CL 502615 to modindex package
+ 2025-07-01 2f653a5a9e crypto/tls: ensure the ECDSA curve matches the signature algorithm
+ 2025-07-01 6e95fd96cc crypto/ecdsa: fix crypto/x509 godoc links
+ 2025-07-01 7755a05209 Revert "crypto/internal/fips140/subtle: add assembly implementation of xorBytes for arm"
+ 2025-07-01 d168ad18e1 slices: update TestIssue68488 to avoid false positives
+ 2025-07-01 27ad1f5013 internal/abi: fix comment on NonEmptyInterface
+ 2025-06-30 86fca3dcb6 encoding/json/jsontext: use bytes.Buffer.AvailableBuffer
+ 2025-06-30 6bd9944c9a encoding/json/v2: avoid escaping jsonopts.Struct
+ 2025-06-30 e46d586edd cmd/compile/internal/escape: add debug hash for literal allocation optimizations
+ 2025-06-30 479b51ee1f cmd/compile/internal/escape: stop disabling literal allocation optimizations when coverage is enabled
+ 2025-06-30 8002d283e8 crypto/tls: update bogo version
+ 2025-06-30 fdd7713fe5 internal/goexperiment: fix godoc formatting
Cherry Mui [Thu, 10 Jul 2025 04:46:00 +0000 (00:46 -0400)]
cmd/link: do size fixups after symbol references are loaded
When we do a size fixup, we need to clone the symbol to an
external symbol so we can modify it. This includes cloning the
relocations, which includes resolving the relocations. If the
symbol being fixed has a relocation referencing a non-Go symbol,
that symbol has not yet been created, it will be resolved to an
empty symbol. Load the references first, so the referenced symbol,
even if it is a non-Go symbol, exists.
Fixes #74537.
Change-Id: I81525bd7c3e232b80eefeb0f18e13ba5331e1510
Reviewed-on: https://go-review.googlesource.com/c/go/+/687315
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com>
Michael Anthony Knyszek [Wed, 9 Jul 2025 15:50:06 +0000 (15:50 +0000)]
runtime: run TestSignalDuringExec in its own process group
TestSignalDuringExec sends a SIGWINCH to the whole process group.
However, it may execute concurrently with other copies of the runtime
tests, especially through `go tool dist`, and gdb version <12.1 has a
bug in non-interactive mode where recieving a SIGWINCH causes a crash.
This change modifies SignalDuringExec in the testprog to first fork
itself into a new process group. To avoid issues with Ctrl+C and the new
process group hanging, the new process blocks on a pipe that is passed
down to it. This pipe is automatically closed when its parent exits,
which should ensure that the subprocess also exits.
Fixes #58932.
Change-Id: I3906afa28cf8b15d22ae612d071bce7f30fc3e6c
Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-longtest-noswissmap,gotip-linux-amd64-longtest-aliastypeparams,gotip-linux-amd64-longtest,gotip-linux-386-longtest
Reviewed-on: https://go-review.googlesource.com/c/go/+/686875
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>
Daniel McCarney [Sat, 28 Jun 2025 18:29:48 +0000 (14:29 -0400)]
crypto/tls: empty server_name conf. ext. from server
When a TLS server uses the information from the server_name extension in
a client hello, and the connection isn't resuming, it should return an
empty server_name extension in its server hello (or encrypted extensions
for TLS 1.3).
For TLS <1.3 we we do this in doFullHandshake(), by setting the
pre-existing serverHelloMsg.serverNameAck bool. We know that the
connection isn't resuming based on the context where this function is
called.
For TLS 1.3, a new encryptedExtensionsMsg.serverNameAck bool is added,
and populated as appropriate in sendServerParameters() based on whether
the conn was resumed or not. The encryptedExtensionsMsg marshalling is
updated to emit the encrypted extension based on that field.
These changes allow enabling the ServerNameExtensionServer-* bogo tests
that verify both the presence and absence of the server_name extension
based on the relevant specifications.
Resolves #74282
Updates #72006
Change-Id: I703bc2ec916b50906bdece7b7483a7faed7aa8e4
Reviewed-on: https://go-review.googlesource.com/c/go/+/684795
TryBot-Bypass: Daniel McCarney <daniel@binaryparadox.net> Reviewed-by: Carlos Amedee <carlos@golang.org> Reviewed-by: Roland Shoemaker <roland@golang.org>
Auto-Submit: Daniel McCarney <daniel@binaryparadox.net>
Roland Shoemaker [Mon, 9 Jun 2025 18:23:46 +0000 (11:23 -0700)]
cmd/go: disable support for multiple vcs in one module
Removes the somewhat redundant vcs.FromDir, "allowNesting" argument,
which was always enabled, and disallow multiple VCS metadata folders
being present in a single directory. This makes VCS injection attacks
much more difficult.
Also adds a GODEBUG, allowmultiplevcs, which re-enables this behavior.
Thanks to RyotaK (https://ryotak.net) of GMO Flatt Security Inc for reporting this issue.
Fixes #74380
Fixes CVE-2025-4674
Change-Id: I5787d90cdca8deb3aca6f154efb627df1e7d2789
Reviewed-on: https://go-review.googlesource.com/c/go/+/686515
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com>
Commit-Queue: Carlos Amedee <carlos@golang.org> Reviewed-by: Carlos Amedee <carlos@golang.org>
Change-Id: I85a4051bd3413bd843b17d22cf9120f615cfe8db
Reviewed-on: https://go-review.googlesource.com/c/go/+/686295 Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Carlos Amedee <carlos@golang.org> Reviewed-by: Carlos Amedee <carlos@golang.org>
Ian Lance Taylor [Mon, 7 Jul 2025 20:01:34 +0000 (13:01 -0700)]
cmd/compile: document that nosplit directive is unsafe
For #74478
Change-Id: I902e9a92cdacb5ad6dafa9896640f8196ba1d56a
Reviewed-on: https://go-review.googlesource.com/c/go/+/686115
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Carlos Amedee <carlos@golang.org>
prove.go used to make my editor and precomit checks very unhappy.
Change-Id: I25f7ffa2191480bc1b4f91fa91ccf3e4768045fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/685818 Reviewed-by: Carlos Amedee <carlos@golang.org> Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
David Chase [Wed, 2 Jul 2025 22:00:12 +0000 (18:00 -0400)]
[dev.simd] cmd/compile: minor tweak for race detector
This makes the front-end a little bit less temp-happy
when instrumenting, which repairs the "is it a constant?"
test in the simd intrinsic conversion which is otherwise
broken by race detection.
Also, this will perhaps be better code.
Change-Id: I84b7a45b7bff62bb2c9f9662466b50858d288645
Reviewed-on: https://go-review.googlesource.com/c/go/+/685637
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Junyang Shao <shaojunyang@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
Michael Anthony Knyszek [Mon, 7 Jul 2025 17:19:17 +0000 (17:19 +0000)]
internal/trace: only test for sync preemption if async preemption is off
Currently, the test change made for the fix to #68090 is flaky. This is
because the sync-point-only goroutine that we expect to be sync
preempted might only ever get async preempted in some circumstances.
This change adds a variant to all trace tests to run with
asyncpreemptoff=1, and the stacks test, the flaky one, only actually
checks for the sync-point in the trace when async preemption is
disabled.
Fixes #74417.
Change-Id: Ib6341bbc26921574b8f0fff6dd521ce83f85499c
Reviewed-on: https://go-review.googlesource.com/c/go/+/686055
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
Michael Matloob [Tue, 1 Jul 2025 21:16:53 +0000 (17:16 -0400)]
cmd/internal/doc: fix GOROOT skew and path joining bugs
Use the goCmd() function to get the go command to invoke, so that when
GOROOT is set, the go command that's invoked uses the same GOROOT.
Otherwise there will be skew between the go command and the tools and
runtime. Also use the environment when determining GOPROXY and
GOMODCACHE, and use url.Join so the slashes in 'http://' aren't
collapsed into one.
Change-Id: Ie36ca2fffdb015a7f5f9bd7f514850e41fad2c1a
Reviewed-on: https://go-review.googlesource.com/c/go/+/685319 Reviewed-by: Michael Matloob <matloob@google.com> Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Filippo Valsorda [Mon, 5 May 2025 11:35:36 +0000 (13:35 +0200)]
crypto/rsa: remove another forgotten note to future self
In CL 226937 I refactored the RSA-PSS implementation, and apparently
left behind a note to think a bit harder about whether this bytes.Equal
check should be constant time or not. It snuck through code review, so
it's 2018 again, no one is worried about pandemics, I have just joined
Google, and I am mailing CL 147637 again.
Anyway, as discussed in #67043 and documented in CL 587277, the inputs
to signature verification functions are not secret, and are allowed to
leak through timing side channels. This means an attacker can already
compute h (from signature and public key) and h0 (from message hash and
public key). What the attacker can't do is produce a signature that
yields the correct h (since that requires the private key).
Change-Id: I6a6a4656d6255bdad628a94f48f7ea878a304263
Reviewed-on: https://go-review.googlesource.com/c/go/+/685255
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Carlos Amedee <carlos@golang.org> Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
cmd/compile/internal/ssa: skip EndSequence entries in TestStmtLines
The TestStmtLines test has been accessing a nil pointer when it
tries to look up LineEntry.File.Name on a line entry with
EndSequence set to true. The doc for EndSequence specifies that if
EndSequence is set, only it and the Address field are meaningful. Skip
the entries with EndSequence set when building the set of files.
I've reproduced this issue locally.
Probably also fixes #49372, but will leave that for a follow-up CL.
Fixes #74475
Updates #49372
Change-Id: Ic0664f7652b52a0a20239d13fe16454622740821
Reviewed-on: https://go-review.googlesource.com/c/go/+/685835 Reviewed-by: Than McIntosh <thanm@golang.org> Reviewed-by: Carlos Amedee <carlos@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Bypass: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Quim Muntal <quimmuntal@gmail.com>
Cherry Mui [Thu, 3 Jul 2025 03:26:44 +0000 (23:26 -0400)]
runtime: correct vdsoSP on S390X
It should get the caller's SP. The current code gets the address
of the first parameter, which is one word above the caller's SP.
There is a slot for saving the LR at 0(SP) in the caller's frame.
Fixes #62086 (for s390x).
Change-Id: Ie8cbfabc8161b98658c884a32e0af72df189ea56
Reviewed-on: https://go-review.googlesource.com/c/go/+/685715 Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Michael Matloob [Tue, 1 Jul 2025 20:28:24 +0000 (16:28 -0400)]
cmd/go/internal/modindex: apply changes in CL 502615 to modindex package
CL 502615 modified go/build to check for invalid import paths, but did
not make those changes to the corresponding code in the modindex
package. Apply those changes here.
We should try to deduplicate the code to prevent this from happening
again.
For #73976
For #74446
Change-Id: I69fc5e2c829efb818c9974ec8126807a1c8f7913
Reviewed-on: https://go-review.googlesource.com/c/go/+/685317
TryBot-Bypass: Michael Matloob <matloob@google.com>
Auto-Submit: Michael Matloob <matloob@golang.org> Reviewed-by: Michael Pratt <mpratt@google.com> Reviewed-by: Michael Matloob <matloob@google.com>
Jorropo [Sat, 28 Jun 2025 00:20:22 +0000 (02:20 +0200)]
slices: update TestIssue68488 to avoid false positives
Fixes #74387
Even tho we are abusing unsafe.SliceData a bit here it's probably fine;
in case this test fail, it means some memory alias is happening
which is not good for GC purposes.
We don't care about false keep alives for stack locations tho.
Change-Id: I9434bad8c6d9fbc39c738690617dc7cf91d82aef
Reviewed-on: https://go-review.googlesource.com/c/go/+/684755 Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Jorropo <jorropo.pgm@gmail.com>
Keith Randall [Thu, 26 Jun 2025 21:36:14 +0000 (14:36 -0700)]
internal/abi: fix comment on NonEmptyInterface
Change-Id: Ia3f4e844049caf11ae67d1bd6dd48350f51c532f
Reviewed-on: https://go-review.googlesource.com/c/go/+/684375 Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@google.com>
before the introduction of bytes.Buffer.AvailableBuffer in March, 2023.
https://go.dev/cl/474635
Updates #71845
Change-Id: I96800e1ba8fce15cc78316779db4ddcd4fe1d510
Reviewed-on: https://go-review.googlesource.com/c/go/+/685136 Reviewed-by: Damien Neil <dneil@google.com>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Joe Tsai [Mon, 30 Jun 2025 22:40:20 +0000 (15:40 -0700)]
encoding/json/v2: avoid escaping jsonopts.Struct
The jsonopts.Struct.join method unfortunately escapes
the receiver because it is passed to JoinUnknownOption,
which is a dynamically implemented function.
This affects jsontext.Encoder.reset and jsontext.Decoder.reset,
which relied on a local jsonopts.Struct to temporarily store
prior options such that it would have to be heap allocated.
Adjust the signature of JoinUnknownOption to avoid pointers
so that nothing escape.
This is a regression from
https://github.com/go-json-experiment/json/pull/163
Performance:
name old time/op new time/op delta
Marshal/Bool-32 72.1ns ± 2% 51.3ns ± 1% -28.77% (p=0.000 n=10+9)
name old allocs/op new allocs/op delta
Marshal/Bool-32 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
Updates #71845
Change-Id: Ife500d82d3d2beb13652553a4ffdf882c136f5a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/685135
Auto-Submit: Joseph Tsai <joetsai@digital-static.net> Reviewed-by: Damien Neil <dneil@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Austin Clements [Mon, 30 Jun 2025 20:42:19 +0000 (16:42 -0400)]
[dev.simd] runtime: remove write barrier in xRegRestore
Currently, there's a write barrier in xRegRestore when it assigns
pp.xRegs.cache = gp.xRegs.state. This is bad because that gets called
on the asyncPreempt return path, where we have really limited stack
space, and we don't currently account for this write barrier.
We can't simply mark xRegState as sys.NotInHeap because it's also
embedded in runtime.p as register scratch space, and runtime.p is heap
allocated.
Hence, to fix this, we rename xRegState to just "xRegs" and introduce
a wrapper "xRegState" type that embeds xRegs and is itself marked
sys.NotInHeap. Then, anywhere we need a manually-managed pointer to
register state, we use the new type.
To ensure this doesn't happen again in the future, we also mark
asyncPreempt2 as go:nowritebarrierrec.
Change-Id: I5ff4841e55ff20047ff7d253ab659ab77aeb3391
Reviewed-on: https://go-review.googlesource.com/c/go/+/684836
Auto-Submit: Austin Clements <austin@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
thepudds [Sat, 28 Jun 2025 20:53:37 +0000 (16:53 -0400)]
cmd/compile/internal/escape: add debug hash for literal allocation optimizations
Several CLs earlier in this stack added optimizations to reduce
user allocations by recognizing and taking advantage of literals,
including CL 649555, CL 649079, and CL 649035.
This CL adds debug hashing of those changes, which enables use of the
bisect tool, such as 'bisect -compile=literalalloc go test -run=Foo'.
This also allows these optimizations to be manually disabled via
'-gcflags=all=-d=literalallochash=n'.
Updates #71359
Change-Id: I854f7742a6efa5b17d914932d61a32b2297f0c88
Reviewed-on: https://go-review.googlesource.com/c/go/+/675415
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
thepudds [Fri, 27 Jun 2025 22:46:27 +0000 (18:46 -0400)]
cmd/compile/internal/escape: stop disabling literal allocation optimizations when coverage is enabled
CL 649079 and CL 649035 updated escape analysis to rewrite certain
expressions in OMAKE and OCONVIFACE nodes as optimizations to
reduce user allocations.
Part of the change in CL 649079 disabled those optimzations when
coverage instrumentation was enabled under an incorrect possible theory
of how those optimizations might be "expected" to change coverage
results -- in particular, the cover_build_pkg_select.txt testscript
failed with different coverage results. I now realize that the proper
explanation is that my fix in CL 684116 was needed.
Now that CL 684116 is merged, we should no longer disable these
optimizations when coverage is enabled, which is what this CL does.
This has not been reported as a problem to my knowledge, but without
this CL, one could imagine for example a test using testing.AllocsPerRun
might start failing when coverage was enabled if the result relied on
these optimizations.
As expected, if we place this CL just before the necessary fix in
CL 684116, the cover_build_pkg_select.txt testscript fails with a
changed coverage result. If we place this CL just after CL 684116,
the test passes, also as expected.
Updates #71359
Change-Id: Ib5ff00c267acd85dd423c238d177e91a4d881f9e
Reviewed-on: https://go-review.googlesource.com/c/go/+/684777 Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
Daniel McCarney [Mon, 23 Jun 2025 19:48:57 +0000 (15:48 -0400)]
crypto/tls: update bogo version
This commit updates the pinned revision of BoringSSL that's used for the
BoGo integration test.
Doing this requires a few categories of config changes:
* ignoring a few new tests for features crypto/tls doesn't implement
* ignoring a few new tests that require further
investigation/classification, or that already have an associated
tracking issue
* updating the error map syntax to accommodate the upstream change that
allows a one-to-many mapping
One code change is required in the shim test process to adjust how we
tear down a connection after an error to account for an upstream change
in the test runner.
Previously, for error conditions we would immediately close the
connection when exiting the shim process. We instead need to do this in
a multi-step process:
1. Flush any pending TLS writes to surface any alerts the error
condition may have generated.
2. Close the write side of the TCP connection to signal we're not
writing anymore.
3. Read and discard any pending data from the peer.
4. Close the read side of the TCP connection to fully close the socket.
Without doing this unpredictable timing factors may result in spurious
test failures where:
1. The runner sends us data that produces an error.
2. We send an alert, and immediately tear down the connection.
3. The runner tries to perform a write, and hits an error because the
pipe is closed.
4. The runner fails the test with the pipe write error, before it reads
from the connection to see the expected alert.
With the new code we instead swallow the unrelated writes and the runner
sees our alert after its ignored write when it tries to read from the
conn. The alert is the expected test outcome, and so the test passes.
This was previously not an issue because the runner was discarding the
write errors.
Updates #72006
Change-Id: Ib72a1c5e693aac92144696c8bae888d5f3f6c32f
Reviewed-on: https://go-review.googlesource.com/c/go/+/683456
Auto-Submit: Daniel McCarney <daniel@binaryparadox.net> Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Roland Shoemaker <roland@golang.org>
[dev.simd] runtime: save scalar registers off stack in amd64 async preemption
Asynchronous preemption must save all registers that could be in use
by Go code. Currently, it saves all of these to the goroutine stack.
As a result, the stack frame requirements of asynchronous preemption
can be rather high. On amd64, this requires 368 bytes of stack space,
most of which is the XMM registers. Several RISC architectures are
around 0.5 KiB.
As we add support for SIMD instructions, this is going to become a
problem. The AVX-512 register state is 2.5 KiB. This well exceeds the
nosplit limit, and even if it didn't, could constrain when we can
asynchronously preempt goroutines on small stacks.
This CL fixes this by moving pure scalar state stored in non-GP
registers off the stack and into an allocated "extended register
state" object. To reduce space overhead, we only allocate these
objects as needed. While in the theoretical limit, every G could need
this register state, in practice very few do at a time.
However, we can't allocate when we're in the middle of saving the
register state during an asynchronous preemption, so we reserve
scratch space on every P to temporarily store the register state,
which can then be copied out to an allocated state object later by Go
code.
This commit only implements this for amd64, since that's where we're
about to add much more vector state, but it lays the groundwork for
doing this on any architecture that could benefit.
Change-Id: I123a95e21c11d5c10942d70e27f84d2d99bbf735
Reviewed-on: https://go-review.googlesource.com/c/go/+/680898 Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Austin Clements <austin@google.com>
Michael Pratt [Fri, 27 Jun 2025 21:21:20 +0000 (17:21 -0400)]
runtime: stash allpSnapshot on the M
findRunnable takes a snapshot of allp prior to dropping the P because
afterwards procresize may mutate allp without synchronization.
procresize is careful to never mutate the contents up to cap(allp), so
findRunnable can still safely access the Ps in the slice.
Unfortunately, growing allp is problematic. If procresize grows the allp
backing array, it drops the reference to the old array. allpSnapshot
still refers to the old array, but allpSnapshot is on the system stack
in findRunnable, which also likely no longer has a P at all.
This means that a future GC will not find the reference and can free the
array and use it for another allocation. This would corrupt later reads
that findRunnable does from the array.
The fix is simple: the M struct itself is reachable by the GC, so we can
stash the snapshot in the M to ensure it is visible to the GC.
The ugliest part of the CL is the cleanup when we are done with the
snapshot because there are so many return/goto top sites. I am tempted
to put mp.clearAllpSnapshot() in the caller and at top to make this less
error prone, at the expensive of extra unnecessary writes.
Fixes #74414.
Change-Id: I6a6a636c484e4f4b34794fd07910b3fffeca830b
Reviewed-on: https://go-review.googlesource.com/c/go/+/684460 Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
Damien Neil [Fri, 27 Jun 2025 15:46:28 +0000 (08:46 -0700)]
sync: disassociate WaitGroups from bubbles on Wait
Fix a race condition in disassociating a WaitGroup in a synctest
bubble from its bubble. We previously disassociated the WaitGroup
when count becomes 0, but this causes problems when an Add call
setting count to 0 races with one incrementing the count.
Instead, disassociate a WaitGroup from its bubble when Wait returns.
Wait must not be called concurrently with an Add call with a
positive delta and a 0 count, so we know that the disassociation
will not race with an Add call trying to create a new association.
Fixes #74386
Change-Id: I9b519519921f7691869a64a245a5ee65d071d054
Reviewed-on: https://go-review.googlesource.com/c/go/+/684635 Reviewed-by: Michael Pratt <mpratt@google.com>
Auto-Submit: Damien Neil <dneil@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
David Chase [Sat, 28 Jun 2025 15:05:44 +0000 (11:05 -0400)]
[dev.simd] cmd/compile: reorder operands for some simd operations
This adds support for one ad hoc reordering, which
requires a new intrinsic-to-ssa helper matching the
name that is used in the generator (and this in the
generated code). In this case, it is opLen{2,3}Imm8_2I
which expects the immediate after the self (0) and
first (1) parameters to the method, and before the
mask if there is one. I.e., the immediate is arg 2
in the call.
The changes to simdintrinsics and stubs are generated
by simdgen CL 684019.
Change-Id: Ia54aab9825d469a2f3efa6d1fb079242181c0ca6
Reviewed-on: https://go-review.googlesource.com/c/go/+/684776 Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Junyang Shao <shaojunyang@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
limeidan [Fri, 13 Jun 2025 03:48:44 +0000 (11:48 +0800)]
runtime: update skips for TestGdbBacktrace
We encountered a new type of "no such process" error on loong64, it's like this
"Couldn't get NT_PRSTATUS registers: No such process.", I checked the source code
of gdb, NT_PRSTATUS is not fixed, it may be another name, so I use regular
expression here to match possible cases.
Updates #50838
Fixes #74389
Change-Id: I3e3f7455b2dc6b8aa10c084f24f6a2a114790855
Reviewed-on: https://go-review.googlesource.com/c/go/+/684195
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: abner chenc <chenguoqi@loongson.cn> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
qmuntal [Fri, 27 Jun 2025 10:45:22 +0000 (12:45 +0200)]
cmd/doc: fix -http on Windows
On Windows, GOMODCACHE almost never starts with a slash, and
"go doc -http" constructs a GOPROXY URL by doing "file://" + GOMODCACHE,
resulting in an invalid file URI.
For example, if GOMODCACHE is "C:\foo", then the file URI should be
"file:///C:/foo", but it becomes "file://C:/foo" instead, where "C:" is
understood as a host name, not a drive letter.
Fixes #74137.
Change-Id: I23e776e0f649a0062e01d1a4a6ea8268ba467331
Reviewed-on: https://go-review.googlesource.com/c/go/+/684575
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Matloob <matloob@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Michael Matloob <matloob@google.com>
Cherry Mui [Fri, 27 Jun 2025 23:45:22 +0000 (19:45 -0400)]
runtime: remove arbitrary 5-second timeout in TestNeedmDeadlock
The NeedmDeadlock test program currently has a 5-second timeout,
which is sort of arbitrary. It is long enough in regular mode
(which usually takes 0.0X seconds), but not quite so for
configurations like ASAN. Instead of using an arbitrary timeout,
just use the test's deadline. The test program is invoked with
testenv.Command, which will send it a SIGQUIT before the deadline
expires.
Fixes #56420 (at least for the asan builder).
Change-Id: I0b13651cb07241401837ca2e60eaa1b83275b093
Reviewed-on: https://go-review.googlesource.com/c/go/+/684697
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Joe Tsai [Fri, 27 Jun 2025 17:59:44 +0000 (10:59 -0700)]
reflect: fix TypeAssert on nil interface values
In the Go language a type assertion of a nil interface value
will always report false:
var err error
v, ok := err.(error) // always reports (nil, false)
Consequently, assertion on a reflect.Value.Interface()
will also report false:
var err error
rv := ValueOf(&err).Elem()
v, ok := rv.Interface().(error) // reports (nil, false)
However, prior to this change, a TypeAssert would report true:
var err error
rv := ValueOf(&err).Elem()
v, ok := TypeAssert[error](rv) // reports (nil, true)
when it should report false.
This fixes TypeAssert to match the Go language by
pushing the typ != v.typ check to the very end after
we have validated that neither v nor T are interface kinds.
Fixes #74404
Change-Id: Ie14d5cf18c8370c3e27ce4bdf4570c89519d8a16
Reviewed-on: https://go-review.googlesource.com/c/go/+/684675 Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net> Reviewed-by: Mateusz Poliwczak <mpoliwczak34@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
qmuntal [Fri, 27 Jun 2025 09:16:54 +0000 (11:16 +0200)]
os: use minimal file permissions when opening parent directory in RemoveAll
On Windows, the process might not have read permission on the parent
directory, but still can delete files in it. This change allows
RemoveAll to open the parent directory with minimal permissions, which
is sufficient for deleting child files.
Fixes #74134.
Cq-Include-Trybots: luci.golang.try:gotip-windows-amd64-longtest,gotip-windows-arm64
Change-Id: I5d5c5977caaebf6e0f93fb2313b0ceb346f70e05
Reviewed-on: https://go-review.googlesource.com/c/go/+/684515 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Damien Neil <dneil@google.com>
Roland Shoemaker [Thu, 26 Jun 2025 19:19:23 +0000 (12:19 -0700)]
encoding/json: add security section to doc
Add a section to the package doc which details the security
considerations of using encoding/json, in particular with respect to
parser misalignment issues.
Additionally, clarify previously ambiguous statement in the Unmarshal
doc about how case is used when matching keys in objects, and add a note
about how duplicate keys are handled.
Fixes #14750
Change-Id: I66f9b845efd98c86a684d7333b3aa8a456564922
Reviewed-on: https://go-review.googlesource.com/c/go/+/684315
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
Auto-Submit: Roland Shoemaker <roland@golang.org> Reviewed-by: Damien Neil <dneil@google.com>
Michael Anthony Knyszek [Fri, 27 Jun 2025 00:59:49 +0000 (00:59 +0000)]
runtime: account for missing frame pointer in preamble
If a goroutine is synchronously preempted, then taking a
frame-pointer-based stack trace at that preemption will skip PC of the
caller of the function which called into morestack. This happens because
the frame pointer is pushed to the stack after the preamble, leaving the
stack in an odd state for frame pointer unwinding.
Deal with this by marking a goroutine as synchronously preempted and
using that signal to load the missing PC from the stack. On LR platforms
this is available in gp.sched.lr. On non-LR platforms like x86, it's at
gp.sched.sp, because there are no args, no locals, and no frame pointer
pushed to the SP yet.
For #68090.
Change-Id: I73a1206d8b84eecb8a96dbe727195da30088f288
Reviewed-on: https://go-review.googlesource.com/c/go/+/684435 Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Nick Ripley <nick.ripley@datadoghq.com>
Andy Nitschke [Tue, 10 Jun 2025 15:09:35 +0000 (11:09 -0400)]
net/http: fix RoundTrip context cancellation for js/wasm
The existing js/wasm implementation of RoundTrip calls abort() on the
fetch() call when the context is canceled but does not wait for for the
resulting promise to be rejected. The result is the failure callback for the
promise will be called at some later point in time when the promise
rejection is handled. In some case this callback may be called after the Go
program has exited resulting in "Go program has already exited" errors.
Fixes #57098
Change-Id: Ia37fd22cb9f667dbb0805ff5db0ceb8fdba7246b
Reviewed-on: https://go-review.googlesource.com/c/go/+/680937 Reviewed-by: Damien Neil <dneil@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Joe Tsai [Fri, 27 Jun 2025 01:18:32 +0000 (18:18 -0700)]
encoding/json: fix typo in hotlink for jsontext.PreserveRawStrings
Updates #71845
Change-Id: Ie099e7ac77293696fd9e69559487e27f4b70ab3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/684416
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Damien Neil <dneil@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Cherry Mui [Thu, 26 Jun 2025 19:46:31 +0000 (15:46 -0400)]
cmd/link: permit a larger size BSS reference to a smaller DATA symbol
Currently, if there is a BSS reference and a DATA symbol
definition with the same name, we pick the DATA symbol, as it
contains the right content. In this case, if the BSS reference
has a larger size, we error out, because it is not safe to access
a smaller symbol as if it has a larger size.
Sometimes code declares a global variable in Go and defines it
in assembly with content. They are expected to be of the same
size. However, in ASAN mode, we insert a red zone for the variable
on the Go side, making it have a larger size, whereas the assembly
symbol is unchanged. This causes the Go reference (BSS) has a
larger size than the assembly definition (DATA). It results in an
error currently. This code is valid and safe, so we should permit
that.
We support this case by increasing the symbol size to match the
larger size (of the BSS side). The symbol content (from the DATA
side) is kept. In some sense, we merge the two symbols. When
loading symbols, it is not easy to change its size (as the object
file may be mapped read-only), so we add it to a fixup list, and
fix it up later after all Go symbols are loaded. This is a very
rare case, so the list should not be long.
We could limit this to just ASAN mode. But it seems okay to allow
this in general. As long as the symbol has the larger size, it is
safe to access it with the larger size.
Fixes #74314.
Change-Id: I3ee6e46161d8f59500e2b81befea11e563355a57
Reviewed-on: https://go-review.googlesource.com/c/go/+/684236
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: David Chase <drchase@google.com>
thepudds [Wed, 25 Jun 2025 23:01:11 +0000 (19:01 -0400)]
cmd/compile/internal/escape: evaluate any side effects when rewriting with literals
CL 649035 and CL 649079 updated escape analysis to rewrite
certain operands in OMAKE and OCONVIFACE nodes from non-constant
expressions to basic literals that evaluate to the same value.
However, when doing that rewriting, we need to evaluate any
side effects prior to replacing the expression, which is what
this CL now does.
Issue #74379 reported a problem with OCONVIFACE nodes due to CL 649079.
CL 649035 has essentially the same issue with OMAKE nodes. To illustrate
that, we add a test for the OMAKE case in fixedbugs/issue74379b.go,
which fails without this change. To avoid introducing an unnecessary
temporary for OMAKE nodes, we also conditionalize the main work of
CL 649035 on whether the OMAKE operand is already an OLITERAL.
CL 649555 and CL 649078 were related changes that created read-only
global storage for composite literals used in an interface conversion.
This CL adds a test in fixedbugs/issue74379c.go to illustrate
that they do not have the same problem.
Updates #71359
Fixes #74379
Change-Id: I6645575ef34f1fe2b0241a22dc205875d66b7ada
Reviewed-on: https://go-review.googlesource.com/c/go/+/684116
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Keith Randall <khr@google.com>
David Chase [Tue, 24 Jun 2025 20:26:47 +0000 (16:26 -0400)]
[dev.simd] cmd/compile: support simd(imm,fp) returns gp
These changes are required to make gp-returning simd
ops work. amd64/ssa.go includes a new code generator
helper, gc/main.go initializes intrinsics AFTER
the types, ssa/_gen/*AMD64.go add another register
shape to the simd ops function.
This CL should be submitted after simdgen CL 683858
which generated some of the changes.
WARNING: This commit contains a breaking change.
This is permissible since jsontext is experimental and
not subject to the Go 1 compatibility agreement.
Existing callers of UnusedBuffer should use AvailableBuffer instead.
Updates #71497
Change-Id: Ib080caf306d545a8fb038e57f0817b18dd0f91cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/683897
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Johan Brandhorst-Satzkorn <johan.brandhorst@gmail.com> Reviewed-by: Damien Neil <dneil@google.com>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
both with methods that return a zero-length buffer that
is intended to only be used with a following Write call.
This keeps the older UnusedBuffer method around so that
at least one commit that has both methods for migration purposes.
Updates #71497
Change-Id: I3815f593e09f645280ae5ad9cbdd63a6c147123b
Reviewed-on: https://go-review.googlesource.com/c/go/+/683896 Reviewed-by: Damien Neil <dneil@google.com>
TryBot-Bypass: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Johan Brandhorst-Satzkorn <johan.brandhorst@gmail.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Cherry Mui [Wed, 25 Jun 2025 19:00:04 +0000 (15:00 -0400)]
[dev.simd] all: merge master (f8ccda2) into dev.simd
Merge List:
+ 2025-06-25 f8ccda2e05 runtime: make explicit nil check in (*spanInlineMarkBits).init
+ 2025-06-25 f069a82998 runtime: note custom GOMAXPROCS even if value doesn't change
+ 2025-06-24 e515ef8bc2 context: fix typo in context_test.go
+ 2025-06-24 47b941f445 cmd/link: add one more linkname to the blocklist
+ 2025-06-24 34cf5f6205 go/types: add test for interface method field type
+ 2025-06-24 6e618cd42a encoding/json: use zstd compressed testdata
+ 2025-06-24 fcb9850859 net/http: reduce allocs in CrossOriginProtection.Check
+ 2025-06-24 11f11f2a00 encoding/json/v2: support ISO 8601 durations
+ 2025-06-24 62deaf4fb8 doc: fix links to runtime Environment Variables
+ 2025-06-24 2e9bb62bfe encoding/json/v2: reject unquoted dash as a JSON field name
+ 2025-06-23 ed7815726d encoding/json/v2: report error on time.Duration without explicit format
+ 2025-06-23 f866958246 cmd/dist: test encoding/json/... with GOEXPERIMENT=jsonv2
+ 2025-06-23 f77a0aa6b6 internal/trace: improve gc-stress test
+ 2025-06-23 4506796a6e encoding/json/jsontext: consistently use JSON terminology
+ 2025-06-23 456a90aa16 runtime: add missing unlock in sysReserveAlignedSbrk
+ 2025-06-23 1cf6386b5e Revert "go/types, types2: don't register interface methods in Info.Types map"
+ 2025-06-20 49cdf0c42e testing, testing/synctest: handle T.Helper in synctest bubbles
+ 2025-06-20 3bf1eecbd3 runtime: fix struct comment
+ 2025-06-20 8ed23a2936 crypto/cipher: fix link to crypto/aes
+ 2025-06-20 ef60769b46 go/doc: add a golden test that reproduces #62640
+ 2025-06-18 8552bcf7c2 cmd/go/internal/fips140: ignore GOEXPERIMENT on error
+ 2025-06-18 4c7567290c runtime: set mspan limit field early and eagerly
+ 2025-06-18 c6ac736288 runtime: prevent mutual deadlock between GC stopTheWorld and suspendG
+ 2025-06-17 53af292aed encoding/json/jsontext: fix spelling error
+ 2025-06-16 d058254689 cmd/dist: always include variant in package names
+ 2025-06-16 3254c2bb83 internal/reflectlite: fix comment about meaning of flag field
+ 2025-06-16 816199e421 runtime: don't let readTrace spin on trace.shutdown
+ 2025-06-16 ea00461b17 internal/trace: make Value follow reflect conventions
+ 2025-06-13 96a6e147b2 runtime: comment that some linknames are used by runtime/trace
+ 2025-06-13 644905891f runtime: remove unused unique.runtime_blockUntilEmptyFinalizerQueue
+ 2025-06-13 683810a368 cmd/link: block new standard library linknames
+ 2025-06-12 9149876112 all: replace a few user-visible mentions of golang.org and godoc.org
+ 2025-06-12 934d5f2cf7 internal/trace: end test programs with SIGQUIT
+ 2025-06-12 5a08865de3 net: remove some BUG entries
+ 2025-06-11 d166a0b03e encoding/json/jsontext, encoding/json/v2: document experimental nature
+ 2025-06-11 d4c6effaa7 cmd/compile: add up-to-date test for generated files
+ 2025-06-10 7fa2c736b3 os: disallow Root.Remove(".") on Plan 9, js, and Windows
+ 2025-06-10 281cfcfc1b runtime: handle system goroutines later in goroutine profiling
+ 2025-06-10 4f86f22671 testing/synctest, runtime: avoid panic when using linker-alloc WG from bubble
Junyang Shao [Tue, 24 Jun 2025 03:59:30 +0000 (03:59 +0000)]
[dev.simd] cmd/compile: glue codes for Shift and Rotate
This CL adds two more intrinsic lowering functions. They can issue an
OpCopy to move a scalar value to vector value. This is needed by Shift
and Rotate APIs.
Change-Id: I8a83197d33207072c4a9221a931e67dddd5cd0bf
Reviewed-on: https://go-review.googlesource.com/c/go/+/683476
Auto-Submit: Junyang Shao <shaojunyang@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
Michael Anthony Knyszek [Wed, 25 Jun 2025 15:47:05 +0000 (15:47 +0000)]
runtime: make explicit nil check in (*spanInlineMarkBits).init
The hugo binary gets slower, potentially dramatically so, with
GOEXPERIMENT=greenteagc. The root cause is page mapping churn. The Green
Tea code introduced a new implicit nil check on value in a
freshly-allocated span to clear some new heap metadata. This nil check
would read the fresh memory, causing Linux to back that virtual address
space with an RO page. This would then be almost immediately written to,
causing Linux to possibly flush the TLB and find memory to replace that
read-only page (likely deduplicated as just the zero page).
This CL fixes the issue by replacing the implicit nil check, which is a
memory read expected to fault if it's truly nil, with an explicit one.
The explicit nil check is a branch, and thus makes no reads to memory.
The result is that the hugo binary no longer gets slower.
No regression test because it doesn't seem possible without access to OS
internals, like Linux tracepoints. We briefly experimented with RSS
metrics, but they're inconsistent. Some system RSS metrics count the
deduplicated zero page, while others (like those produced by
/proc/self/smaps) do not.
Instead, we'll add a new benchmark to our benchmark suite, separately.
For #73581.
Fixes #74375.
Change-Id: I708321c14749a94ccff55072663012eba18b3b91
Reviewed-on: https://go-review.googlesource.com/c/go/+/684015 Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@google.com>