cmd/link: generate Mach-O UUID when -B flag is specified

Currently, on Mach-O, the Go linker doesn't generate LC_UUID in
internal linking mode. This causes some macOS system tools unable
to track the binary, as well as in some cases the binary unable
to access local network on macOS 15.

This CL makes the linker start generate LC_UUID. Currently, the
UUID is generated if the -B flag is specified. And we'll make it
generate UUID by default in a later CL. The -B flag is currently
for generating GNU build ID on ELF, which is a similar concept to
Mach-O's UUID. Instead of introducing another flag, we just use
the same flag and the same setting. Specifically, "-B gobuildid"
will generate a UUID based on the Go build ID.

For #68678.

Cq-Include-Trybots: luci.golang.try:gotip-darwin-amd64_14,gotip-darwin-arm64_13
Change-Id: I90089a78ba144110bf06c1c6836daf2d737ff10a
Reviewed-on: https://go-review.googlesource.com/c/go/+/618595
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Ingo Oeser <nightlyone@googlemail.com>
Reviewed-by: Than McIntosh <thanm@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: execute publicationBarrier in noscan case for delayed zeroing

This is a peace-of-mind change to make sure that delayed-zeroed memory
(in the large alloc case) is globally visible from the moment the
allocation is published back to the caller.

The way it's written right now is good enough for the garbage collector
(we already have a publication barrier for a nil span.largeType, so the
GC will ignore the noscan span) but this might matter for user code on
weak memory architectures.

Change-Id: I06ac9b95863074e5f09382629083b19bfa87fdb8
Reviewed-on: https://go-review.googlesource.com/c/go/+/619036
Reviewed-by: Keith Randall <khr@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@golang.org>

runtime: specialize heapSetType

Last CL we separated mallocgc into several specialized paths. Let's
split up heapSetType too. This will make the specialized heapSetType
functions inlineable and cut out some branches as well as a function
call.

Microbenchmark results at this point in the stack:

                   │ before.out  │            after-5.out             │
                   │   sec/op    │   sec/op     vs base               │
Malloc8-4            13.52n ± 3%   12.15n ± 2%  -10.13% (p=0.002 n=6)
Malloc16-4           21.49n ± 2%   18.32n ± 4%  -14.75% (p=0.002 n=6)
MallocTypeInfo8-4    27.12n ± 1%   18.64n ± 2%  -31.30% (p=0.002 n=6)
MallocTypeInfo16-4   28.71n ± 3%   21.63n ± 5%  -24.65% (p=0.002 n=6)
geomean              21.81n        17.31n       -20.64%

Change-Id: I5de9ac5089b9eb49bf563af2a74e6dc564420e05
Reviewed-on: https://go-review.googlesource.com/c/go/+/614795
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>

runtime: refactor mallocgc into several independent codepaths

Right now mallocgc is a monster of a function. In real programs, we see
that a substantial amount of time in mallocgc is spent in mallocgc
itself. It's very branch-y, holds a lot of state, and handles quite a few
disparate cases, trying to merge them together.

This change breaks apart mallocgc into separate, leaner functions.
There's some duplication now, but there are a lot of branches that can
be pruned as a result.

There's definitely still more we can do here. heapSetType can be inlined
and broken down for each case, since its internals roughly map to each
case anyway (done in a follow-up CL). We can probably also do more with
the size class lookups, since we know more about the size of the object
in each case than before.

Below are the savings for the full stack up until now.

                    │ after-3.out │              after-4.out              │
                    │   sec/op    │     sec/op      vs base               │
Malloc8-4             13.32n ± 2%   12.17n ±  1%     -8.63% (p=0.002 n=6)
Malloc16-4            21.64n ± 3%   19.38n ± 10%    -10.47% (p=0.002 n=6)
MallocTypeInfo8-4     23.15n ± 2%   19.91n ±  2%    -14.00% (p=0.002 n=6)
MallocTypeInfo16-4    25.86n ± 4%   22.48n ±  5%    -13.11% (p=0.002 n=6)
MallocLargeStruct-4                 270.0n ±   ∞ ¹
geomean               20.38n        30.97n          -11.58%

Change-Id: I681029c0b442f9221c4429950626f06299a5cfe4
Reviewed-on: https://go-review.googlesource.com/c/go/+/614257
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@golang.org>

runtime: break out the debug.malloc codepaths into functions

This change breaks out the debug.malloc codepaths into dedicated
functions, both for making mallocgc easier to read, and to reduce the
function's size (currently all that code is inlined and really doesn't
need to be).

This is a microoptimization that on its own changes very little, but
together with other optimizations and a breaking up of the various
malloc paths will matter all together ("death by a thousand cuts").

Change-Id: I30b3ab4a1f349ba85b4a1b5b2c399abcdfe4844f
Reviewed-on: https://go-review.googlesource.com/c/go/+/617879
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: move debug checks behind constant flag in mallocgc

These debug checks are very occasionally helpful, but they do cost real
time. The biggest issue seems to be the bloat of mallocgc due to the
"throw" paths. Overall, after some follow-ups, this change cuts about
1ns off of the mallocgc fast path.

This is a microoptimization that on its own changes very little, but
together with other optimizations and a breaking up of the various
malloc paths will matter all together ("death by a thousand cuts").

Change-Id: I07c4547ad724b9f94281320846677fb558957721
Reviewed-on: https://go-review.googlesource.com/c/go/+/617878
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>

runtime: rename shouldhelpgc to checkGCTrigger in mallocgc

shouldhelpgc is a very unhelpful name, because it has nothing to do with
assists and solely to do with GC triggering. Name it checkGCTrigger
instead, which is much clearer.

Change-Id: Id38debd424ddb397376c0cea6e74b3fe94002f71
Reviewed-on: https://go-review.googlesource.com/c/go/+/617877
Reviewed-by: Keith Randall <khr@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@golang.org>

runtime: recompute assistG before and after malloc

This change stops tracking assistG across malloc to reduce number of
slots the compiler must keep track of in mallocgc, which adds to
register pressure. It also makes the call to deductAssistCredit only
happen if the GC is running.

This is a microoptimization that on its own changes very little, but
together with other optimizations and a breaking up of the various
malloc paths will matter all together ("death by a thousand cuts").

Change-Id: I4cfac7f3e8e873ba66ff3b553072737a4707e2c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/617876
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>

runtime: use wb flag instead of gcphase for allocate-black check

This is an allocator microoptimization. There's no reason to check
gcphase in general, since it's mostly for debugging anyway.
writeBarrier.enabled is set in all the same cases here, and we force one
fewer cache line (probably) to be touched during malloc.

Conceptually, it also makes a bit more sense. The allocate-black policy
is partly informed by the write barrier design.

Change-Id: Ia5ff593d64c29cf7f4d1bced3204056566444a98
Reviewed-on: https://go-review.googlesource.com/c/go/+/617875
Reviewed-by: Keith Randall <khr@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@golang.org>

runtime: simplify mem profile checking in mallocgc

Checking whether the current allocation needs to be profiled is
currently branch-y and weirdly a lot of code. The branches are
generally predictable, but it's a surprising number of instructions.
Part of the problem is that MemProfileRate is just a global that can be
set at any time, so we need to load it and check certain settings
explicitly. In an ideal world, we would just always subtract from
nextSample and have a single branch to take the slow path if we
subtract below zero.

If MemProfileRate were a function, we could trash all the nextSample
values intentionally in each mcache. This would be slow, but
MemProfileRate changes rarely while the malloc hot path is well, hot.
Unfortunate...

Although this ideal world is, AFAICT, impossible, we can still get
close. If we cache the value of MemProfileRate in each mcache, then we
can force malloc to take the slow path whenever MemProfileRate changes.
This does require two additional loads, but crucially, these loads are
independent of everything else in mallocgc. Furthermore, the branch
dependent on those loads is incredibly predictable in practice.

This CL on its own has little-to-no impact on mallocgc. But this
codepath is going to be duplicated in several places in the next CL, so
it'll pay to simplify it. Also, we're very much trying to remedy a
death-by-a-thousand-cuts situation, and malloc is currently still kind
of a monster -- it will not help if mallocgc isn't really streamlined
itself.

Lastly, there's a nice property now that all nextSample values get
immediately re-sampled when MemProfileRate changes.

Change-Id: I6443d0cf9bd7861595584442b675ac1be8ea3455
Reviewed-on: https://go-review.googlesource.com/c/go/+/615815
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>

encoding/xml: document that embedded interfaces look like non-embedded ones

Fixes #69941

Change-Id: Icc3c88d57c14fa9ca203c693d67f144686fed8cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/621076
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

runtime: optimize 8-byte allocation pointer data writing

This change brings back a minor optimization lost in the Go 1.22 cycle
wherein the 8-byte pointer-ful span class spans would have the pointer
bitmap written ahead of time in bulk, because there's only one possible
pattern.

                  │   before    │               after               │
                  │   sec/op    │   sec/op     vs base              │
MallocTypeInfo8-4   25.13n ± 1%   23.59n ± 2%  -6.15% (p=0.002 n=6)

Change-Id: I135b84bb1d5b7e678b841b56430930bc73c0a038
Reviewed-on: https://go-review.googlesource.com/c/go/+/614256
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: don't call span.heapBits in writeHeapBitsSmall

For whatever reason, span.heapBits is kind of slow. It accounts for
about a quarter of the cost of writeHeapBitsSmall, which is absurd. We
get a nice speed improvement for small allocations by eliminating this
call.

                   │   before    │               after               │
                   │   sec/op    │   sec/op     vs base              │
MallocTypeInfo16-4   29.47n ± 1%   27.02n ± 1%  -8.31% (p=0.002 n=6)

Change-Id: I6270e26902e5a9254cf1503fac81c3c799c59d6a
Reviewed-on: https://go-review.googlesource.com/c/go/+/614255
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>

cmd/compile,internal/runtime/maps: add extendible hashing

Extendible hashing splits a swisstable map into many swisstables. This
keeps grow operations small.

For #54766.

Cq-Include-Trybots: luci.golang.try:gotip-linux-ppc64_power10,gotip-linux-amd64-longtest-swissmap
Change-Id: Id91f34af9e686bf35eb8882ee479956ece89e821
Reviewed-on: https://go-review.googlesource.com/c/go/+/604936
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>

cmd/asm: add position to PCALIGN directives

This allows PCALIGN to be used in the end-to-end assembly
tests without causing an error due to missing file position.

Change-Id: Iadea2875854ffd544a963acd21293dc9840da2d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/620635
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

runtime: revise the documentation comments for netpoll

Supplement to CL 511455.

Updates #61454

Change-Id: I111cbf297dd9159cffba333d610a7a4542915c55
GitHub-Last-Rev: fe8fa184868d665a4d08d534d3bfb5ea446d12c0
GitHub-Pull-Request: golang/go#69900
Reviewed-on: https://go-review.googlesource.com/c/go/+/620495
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

syscall: skip TestSetuidEtc when root's gid is not 0

When the root user belongs to a special user group
(for example, in a mock environment), TestSetuidEtc will fail.

For example: Setegid(1)
want:"Gid: 0 1 0 1"
got:"Gid: 1001 1 1001 1"

Fixes #69921

Change-Id: I74d0a006b7529b1b569120a067eb4d7c4ed2e491
GitHub-Last-Rev: 5724383eb134c8a5c2a4a5ed67e2d3999073b98b
GitHub-Pull-Request: golang/go#69922
Reviewed-on: https://go-review.googlesource.com/c/go/+/620775
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

cmd/link: check if the trampoline is actually added

Change-Id: I2ddffe9118fd9954d9bae60c92fd8fc5b311b93a
Reviewed-on: https://go-review.googlesource.com/c/go/+/603736
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>

go/ast: document invalid raw string literal end position containing carriage returns

Fixes #69861

Change-Id: Id1684ee7d0c04262119d9e61f914bb9ecc0ef438
GitHub-Last-Rev: 5ad182c51aeb8b26631c6a97a7e9a2d89405ec06
GitHub-Pull-Request: golang/go#69862
Reviewed-on: https://go-review.googlesource.com/c/go/+/619835
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>

runtime: more thorough map benchmarks

Based on the benchmarks in github.com/cockroachlabs/swiss.

For #54766.

Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-longtest-swissmap
Change-Id: I9ad925d3272c671e21ec04eb2da5ebd8f0fc6a28
Reviewed-on: https://go-review.googlesource.com/c/go/+/596295
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: 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>
Auto-Submit: Michael Pratt <mpratt@google.com>

internal/runtime/atomic: add Xchg8 for 386

For #69735

Change-Id: I5b9f57315d693d613dc88dc02c10bee39aeeef76
GitHub-Last-Rev: 690337e5b81a48bdcb808526d0c5f4837e8912b7
GitHub-Pull-Request: golang/go#69923
Reviewed-on: https://go-review.googlesource.com/c/go/+/620756
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Keith Randall <khr@golang.org>

runtime/testdata: fix for C23 nullptr keyword

src/runtime/testdata/testprogcgo/threadprof.go contains C code with a
variable called nullptr.  This conflicts with the nullptr keyword in
the C23 revision of the C standard (showing up as gccgo test build
failures when updating GCC to use C23 by default when building C
code).

Rename that variable to nullpointer to avoid the clash with the
keyword (any other name that's not a keyword would work just as well).

Change-Id: Ida5ef371a3f856c611409884e185c3d5ded8e86c
GitHub-Last-Rev: 2ec464703be0507a67a077741789a37511d197e4
GitHub-Pull-Request: golang/go#69927
Reviewed-on: https://go-review.googlesource.com/c/go/+/620955
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

os: add precondition doc for Create and OpenFile

Fixes #69836

Change-Id: Ide243c2aa9c6f9d45976f728f97e32c4fbadb720
Reviewed-on: https://go-review.googlesource.com/c/go/+/619316
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

cmd/compile: omit saved .closureptr in optimized code

This worsens debugging, but improves performance.

Change-Id: I7f3c0d174823b3de412478f9537adc61ae4c076e
Reviewed-on: https://go-review.googlesource.com/c/go/+/620219
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>

syscall: keep write access when O_TRUNC is used on Windows

CL 618836 introduces a regression where O_APPEND and O_TRUNC could
not be used together on Windows.

This CL fixes the issue by keeping the write access when O_TRUNC is used
, which is required when overwriting data (as per the file
access rights docs: https://learn.microsoft.com/en-us/windows/win32/fileio/file-access-rights-constants).

Fixes #69902.

Change-Id: I77ec60ca6929124dd4490bdad6c3280c4db3efcb
Reviewed-on: https://go-review.googlesource.com/c/go/+/620575
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>

cmd/compile: add patterns for bitfield opcodes on loong64

goos: linux
goarch: loong64
pkg: math/bits
cpu: Loongson-3A6000 @ 2500.00MHz
                |  bench.old   |              bench.new               |
                |    sec/op    |    sec/op     vs base                |
LeadingZeros      1.0095n ± 0%   0.8011n ± 0%  -20.64% (p=0.000 n=10)
LeadingZeros8      1.201n ± 0%    1.167n ± 0%   -2.83% (p=0.000 n=10)
LeadingZeros16     1.201n ± 0%    1.167n ± 0%   -2.83% (p=0.000 n=10)
LeadingZeros32     1.201n ± 0%    1.134n ± 0%   -5.58% (p=0.000 n=10)
LeadingZeros64    0.8007n ± 0%   1.0115n ± 0%  +26.32% (p=0.000 n=10)
TrailingZeros     0.8054n ± 0%   0.8106n ± 1%   +0.65% (p=0.000 n=10)
TrailingZeros8     1.067n ± 0%    1.002n ± 1%   -6.09% (p=0.000 n=10)
TrailingZeros16   1.0540n ± 0%   0.8389n ± 0%  -20.40% (p=0.000 n=10)
TrailingZeros32   0.8014n ± 0%   0.8117n ± 0%   +1.29% (p=0.000 n=10)
TrailingZeros64   0.8015n ± 0%   0.8124n ± 1%   +1.36% (p=0.000 n=10)
OnesCount          3.418n ± 0%    3.417n ± 0%        ~ (p=0.911 n=10)
OnesCount8        0.8004n ± 0%   0.8004n ± 0%        ~ (p=1.000 n=10)
OnesCount16        1.440n ± 0%    1.299n ± 0%   -9.79% (p=0.000 n=10)
OnesCount32        2.969n ± 0%    2.940n ± 0%   -0.94% (p=0.000 n=10)
OnesCount64        3.563n ± 0%    3.558n ± 0%   -0.14% (p=0.000 n=10)
RotateLeft        0.6677n ± 0%   0.6670n ± 0%        ~ (p=0.055 n=10)
RotateLeft8        1.318n ± 1%    1.321n ± 0%        ~ (p=0.117 n=10)
RotateLeft16      0.8457n ± 1%   0.8442n ± 0%        ~ (p=0.325 n=10)
RotateLeft32      0.8004n ± 0%   0.8004n ± 0%        ~ (p=0.837 n=10)
RotateLeft64      0.6678n ± 0%   0.6670n ± 0%   -0.13% (p=0.000 n=10)
Reverse           0.8004n ± 0%   0.8004n ± 0%        ~ (p=1.000 n=10)
Reverse8          0.6989n ± 0%   0.6969n ± 1%        ~ (p=0.138 n=10)
Reverse16         0.6998n ± 1%   0.7004n ± 1%        ~ (p=0.985 n=10)
Reverse32         0.4158n ± 1%   0.4159n ± 1%        ~ (p=0.870 n=10)
Reverse64         0.4165n ± 1%   0.4194n ± 2%        ~ (p=0.093 n=10)
ReverseBytes      0.8004n ± 0%   0.8004n ± 0%        ~ (p=1.000 n=10)
ReverseBytes16    0.4183n ± 2%   0.4148n ± 1%        ~ (p=0.055 n=10)
ReverseBytes32    0.4143n ± 2%   0.4153n ± 1%        ~ (p=0.869 n=10)
ReverseBytes64    0.4168n ± 1%   0.4177n ± 1%        ~ (p=0.184 n=10)
Add                1.201n ± 0%    1.201n ± 0%        ~ (p=0.087 n=10)
Add32              1.603n ± 0%    1.601n ± 0%   -0.12% (p=0.000 n=10)
Add64              1.201n ± 0%    1.201n ± 0%        ~ (p=0.211 n=10)
Add64multiple      1.839n ± 0%    1.835n ± 0%   -0.24% (p=0.001 n=10)
Sub                1.202n ± 0%    1.201n ± 0%   -0.04% (p=0.033 n=10)
Sub32              2.401n ± 0%    1.601n ± 0%  -33.32% (p=0.000 n=10)
Sub64              1.201n ± 0%    1.201n ± 0%        ~ (p=1.000 n=10)
Sub64multiple      2.105n ± 0%    2.096n ± 0%   -0.40% (p=0.000 n=10)
Mul               0.8008n ± 0%   0.8004n ± 0%   -0.05% (p=0.000 n=10)
Mul32             0.8041n ± 0%   0.8014n ± 0%   -0.34% (p=0.000 n=10)
Mul64             0.8008n ± 0%   0.8004n ± 0%   -0.05% (p=0.000 n=10)
Div                8.977n ± 0%    8.945n ± 0%   -0.36% (p=0.000 n=10)
Div32              4.084n ± 0%    4.086n ± 0%        ~ (p=0.445 n=10)
Div64              9.316n ± 0%    9.301n ± 0%   -0.17% (p=0.000 n=10)
geomean            1.141n         1.117n        -2.09%

Change-Id: I4dc1eaab6728f771bc722ed331fe5c6429bd1037
Reviewed-on: https://go-review.googlesource.com/c/go/+/618475
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Meidan Li <limeidan@loongson.cn>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
Reviewed-by: Qiqi Huang <huangqiqi@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

cmd/compile: optimize loong64 with register indexed load/store

goos: linux
goarch: loong64
pkg: test/bench/go1
cpu: Loongson-3A6000 @ 2500.00MHz
                      |  bench.old  |              bench.new              |
                      |   sec/op    |   sec/op     vs base                |
BinaryTree17             7.766 ± 1%    7.640 ± 2%   -1.62% (p=0.000 n=20)
Fannkuch11               2.649 ± 0%    2.358 ± 0%  -10.96% (p=0.000 n=20)
FmtFprintfEmpty         35.89n ± 0%   35.87n ± 0%   -0.06% (p=0.000 n=20)
FmtFprintfString        59.44n ± 0%   57.25n ± 2%   -3.68% (p=0.000 n=20)
FmtFprintfInt           62.07n ± 0%   60.04n ± 0%   -3.27% (p=0.000 n=20)
FmtFprintfIntInt        97.90n ± 0%   97.26n ± 0%   -0.65% (p=0.000 n=20)
FmtFprintfPrefixedInt   116.7n ± 0%   119.2n ± 0%   +2.14% (p=0.000 n=20)
FmtFprintfFloat         204.5n ± 0%   201.9n ± 0%   -1.30% (p=0.000 n=20)
FmtManyArgs             455.9n ± 0%   466.8n ± 0%   +2.39% (p=0.000 n=20)
GobDecode               7.458m ± 1%   7.138m ± 1%   -4.28% (p=0.000 n=20)
GobEncode               8.573m ± 1%   8.473m ± 1%        ~ (p=0.091 n=20)
Gzip                    280.2m ± 0%   284.9m ± 0%   +1.67% (p=0.000 n=20)
Gunzip                  32.68m ± 0%   32.67m ± 0%        ~ (p=0.211 n=20)
HTTPClientServer        54.22µ ± 0%   53.24µ ± 0%   -1.80% (p=0.000 n=20)
JSONEncode              9.427m ± 1%   9.152m ± 0%   -2.92% (p=0.000 n=20)
JSONDecode              47.08m ± 1%   46.85m ± 1%   -0.49% (p=0.007 n=20)
Mandelbrot200           4.601m ± 0%   4.605m ± 0%   +0.08% (p=0.000 n=20)
GoParse                 4.776m ± 0%   4.655m ± 1%   -2.52% (p=0.000 n=20)
RegexpMatchEasy0_32     59.77n ± 0%   57.59n ± 0%   -3.66% (p=0.000 n=20)
RegexpMatchEasy0_1K     458.1n ± 0%   458.8n ± 0%   +0.15% (p=0.000 n=20)
RegexpMatchEasy1_32     59.36n ± 0%   59.24n ± 0%   -0.20% (p=0.000 n=20)
RegexpMatchEasy1_1K     557.7n ± 0%   560.2n ± 0%   +0.46% (p=0.000 n=20)
RegexpMatchMedium_32    803.1n ± 0%   772.8n ± 0%   -3.77% (p=0.000 n=20)
RegexpMatchMedium_1K    27.29µ ± 0%   25.88µ ± 0%   -5.18% (p=0.000 n=20)
RegexpMatchHard_32      1.385µ ± 0%   1.304µ ± 0%   -5.85% (p=0.000 n=20)
RegexpMatchHard_1K      40.92µ ± 0%   39.58µ ± 0%   -3.27% (p=0.000 n=20)
Revcomp                 474.3m ± 0%   410.0m ± 0%  -13.56% (p=0.000 n=20)
Template                78.16m ± 0%   76.32m ± 1%   -2.36% (p=0.000 n=20)
TimeParse               271.8n ± 0%   272.1n ± 0%   +0.11% (p=0.000 n=20)
TimeFormat              292.3n ± 0%   294.8n ± 0%   +0.86% (p=0.000 n=20)
geomean                 51.98µ        50.82µ        -2.22%

Change-Id: Ia78f1ddee8f1d9ec7192a4b8d2a4ec6058679956
Reviewed-on: https://go-review.googlesource.com/c/go/+/615918
Reviewed-by: Qiqi Huang <huangqiqi@loongson.cn>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>

time: correct time.AppendText's error message

"time.AppendText" returns error messages that start with the prefix
"time.MarshalText: " which seems confusion.

Now correct the message prefix to "time.AppendText: " and add a test
to prevent regression.

Change-Id: I5742c9c3ed802eb79c65d459910deae4f3652ffd
GitHub-Last-Rev: ce965595c1dafab4a3db3d3f9f9edc9e43c5dea2
GitHub-Pull-Request: golang/go#69914
Reviewed-on: https://go-review.googlesource.com/c/go/+/620597
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

go/internal/gcimporter: drop indexed import

The compiler hasn't emitted indexed export data files since go1.19,
so this code, which is only statically reachable from
go/importer.For("gc") aka importer.Default(), is not dynamically
reachable since those files will not be in indexed format.

Updates #68898

Change-Id: I12ea4e1b88da4fffdc9a07f318b9445a61e0d02b
Reviewed-on: https://go-review.googlesource.com/c/go/+/620135
Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Alan Donovan <adonovan@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

strconv: display format options as list

Fixes #69890

Change-Id: I1da4eb76c008679a687f4faa4294fe32b5fc7f42
Reviewed-on: https://go-review.googlesource.com/c/go/+/620236
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

crypto/tls: include close notify in client tls test recordings

This commit fixes the issue where tls testdata recordings made with the
newer version of the prerecorded tls conversation test harness, doesn't
end up capturing the final close notify message. The fix simply ensures
that the tls.Client closes before the recording of the conversation is
closed. The closing of the client connection directly is no longer
needed when updating the recording since it will be closed when the
tls.Client is closed.

Fixes golang/go#69846

Change-Id: I93898de32abd89659a32ed240df6daea5aeaa7fc
Reviewed-on: https://go-review.googlesource.com/c/go/+/620395
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

os: use relative paths in a test dir in TestOpenError

Refactor TestOpenError to use relative paths in test cases,
in preparation for extending it to test os.Root.

Use a test temporary directory instead of system directory
with presumed-known contents.

Move the testcase type and case definitions inline with the test.

For #67002

Change-Id: Idc53dd9fcecf763d3e4eb3b4643032e3003d7ef4
Reviewed-on: https://go-review.googlesource.com/c/go/+/620157
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

timer: fix Stop link in Timer.Reset doc comment

Change-Id: I0fccb18b2d5d3f7c86f026c988f90734546f7be0
GitHub-Last-Rev: a72cfe970e74dd3a9fffec9604ae58126514542c
GitHub-Pull-Request: golang/go#69856
Reviewed-on: https://go-review.googlesource.com/c/go/+/619056
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>

internal/syscall/windows: fix handle leak in Mkdirat

Mkdirat does not close the handle returned by CreateFile, but it should.

Mkdirat has been introduced in this developer cycle, so it is not
necessary to backport this fix to any release branch.

Change-Id: Icddac5ccdc6a142a5be5392a39aba2ae7cc9c69a
Reviewed-on: https://go-review.googlesource.com/c/go/+/620195
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Quim Muntal <quimmuntal@gmail.com>

runtime: clarify work.bytesMarked documentation

Change-Id: If5132400aac0ef00e467958beeaab5e64d053d10
Reviewed-on: https://go-review.googlesource.com/c/go/+/619099
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Austin Clements <austin@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

all: wire up swisstable maps

Use the new SwissTable-based map in internal/runtime/maps as the basis
for the runtime map when GOEXPERIMENT=swissmap.

Integration is complete enough to pass all.bash. Notable missing
features:

* Race integration / concurrent write detection
* Stack-allocated maps
* Specialized "fast" map variants
* Indirect key / elem

For #54766.

Cq-Include-Trybots: luci.golang.try:gotip-linux-ppc64_power10,gotip-linux-amd64-longtest-swissmap
Change-Id: Ie97b656b6d8e05c0403311ae08fef9f51756a639
Reviewed-on: https://go-review.googlesource.com/c/go/+/594596
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: don't frob isSending for tickers

The Ticker Stop and Reset methods don't report a value,
so we don't need to track whether they are interrupting a send.

This includes a test that used to fail about 2% of the time on
my laptop when run under x/tools/cmd/stress.

Change-Id: Ic6d14b344594149dd3c24b37bbe4e42e83f9a9ad
Reviewed-on: https://go-review.googlesource.com/c/go/+/620136
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

cmd/cgo/internal/testsanitizers: correct comment in tsan test

Change-Id: Id22ad7c92c54bc61f1f1d5544f17208f2f8648aa
GitHub-Last-Rev: 61eee331dc2da16358425440e5630117f45d5182
GitHub-Pull-Request: golang/go#69866
Reviewed-on: https://go-review.googlesource.com/c/go/+/619836
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

cmd/cgo,cmd/go: preallocate slices if they have known fixed capacities

This allows for more efficient use of memory.

Change-Id: I16f399a25c23b804e55289ca055fa83ea9862f16
GitHub-Last-Rev: 19bb96a7cf4d27c085cfdb074905c4bf34eb660d
GitHub-Pull-Request: golang/go#69841
Reviewed-on: https://go-review.googlesource.com/c/go/+/618960
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>

math: implement arch{Floor, Ceil, Trunc} in hardware on loong64

benchmark:

goos: linux
goarch: loong64
pkg: math
cpu: Loongson-3A6000 @ 2500.00MHz
        │  bench.old   │              bench.new              │
        │    sec/op    │   sec/op     vs base                │
Ceil      10.810n ± 0%   2.578n ± 0%  -76.15% (p=0.000 n=20)
Floor     10.810n ± 0%   2.531n ± 0%  -76.59% (p=0.000 n=20)
Trunc      9.606n ± 0%   2.530n ± 0%  -73.67% (p=0.000 n=20)
geomean    10.39n        2.546n       -75.50%

goos: linux
goarch: loong64
pkg: math
cpu: Loongson-3A5000 @ 2500.00MHz
        │  bench.old   │              bench.new              │
        │    sec/op    │   sec/op     vs base                │
Ceil      13.220n ± 0%   7.703n ± 8%  -41.73% (p=0.000 n=20)
Floor     12.410n ± 0%   7.248n ± 2%  -41.59% (p=0.000 n=20)
Trunc     11.210n ± 0%   7.757n ± 4%  -30.80% (p=0.000 n=20)
geomean    12.25n        7.566n       -38.25%

Change-Id: I3af51e9852e9cf5f965fed895d68945a2e8675f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/612615
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

net: use slices.Contains{,Func} in lookup tests

Change-Id: I66199995ca34c92aeb8234b43cb2166f2976c903
Reviewed-on: https://go-review.googlesource.com/c/go/+/619735
Auto-Submit: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>

internal/syscall/windows: add Openat, Mkdirat

Windows versions of openat and mkdirat,
implemented using NtCreateFile.

For #67002

Change-Id: If43b1c1069733e5c45f7d45a69699fec30187308
Reviewed-on: https://go-review.googlesource.com/c/go/+/619435
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Quim Muntal <quimmuntal@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

cmd/go: add file names for cyclic import error

The PR is to add more details for the error, so that it would be easier to troubleshoot the cyclic imports error.

The change for the error looks like the following:

package cyclic-import-example
        imports cyclic-import-example/packageA from /Users/personal/cyclic-import-example/main.go:4:5
        imports cyclic-import-example/packageB from /Users/personal/cyclic-import-example/packageA/a.go:5:2
        imports cyclic-import-example/packageA from /Users/personal/cyclic-import-example/packageB/bb.go:5:2: import cycle not allowed

Fixes #66078

Change-Id: I162cd348004bf4e4774b195f8355151c1bf0a652
GitHub-Last-Rev: c5a16256d1b5bb4d720c72624a44477be20da743
GitHub-Pull-Request: golang/go#68337
Reviewed-on: https://go-review.googlesource.com/c/go/+/597035
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: reduce syscall.SyscallX stack usage

syscall.SyscallX consumes a lot of stack space, which is a problem
because they are nosplit functions. They used to use less stack space,
but CL 563315, that landed in Go 1.23, increased the stack usage by a
lot.

This CL reduces the stack usage back to the previous level.

Fixes #69813.

Change-Id: Iddedd28b693c66a258da687389768055c493fc2e
Reviewed-on: https://go-review.googlesource.com/c/go/+/618497
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

cmd/go: make sure the linker for shared doesn't include tempdir path

This is similar to CL 478196 and CL 477296,
but this is for -buildmode=shared.

When using "go install -buildmode=shared std",
because the gold linker is used by default on Linux arm64,
it will cause temporary paths to be included in libstd.so.

Based on the changes of CL 478196,
I speculate that this may also have issues on other platforms.
So, this change is for all platform.

Fixes #69464

Change-Id: I4493c82be030186e61aef597ea0e6f43bcf95a32
GitHub-Last-Rev: ee40cf81acf70f553bfc63a21a41ce0174857043
GitHub-Pull-Request: golang/go#69394
Reviewed-on: https://go-review.googlesource.com/c/go/+/612396
Reviewed-by: Michael Matloob <matloob@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: David Chase <drchase@google.com>

syscall: support more flags when opening directories on Windows

syscall.Open was artificially limiting the flags that were eligible
to open directories on Windows. This change extend the cases where we
pass FILE_FLAG_BACKUP_SEMANTICS to all flag combinations allowed by
Unix.

Change-Id: Ia7c083bcba070f92ea61c6d67487bdefd0d99546
Reviewed-on: https://go-review.googlesource.com/c/go/+/619295
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Damien Neil <dneil@google.com>

syscall: fix Open param names

syscall.Open param names are confusing, mainly because what should be
named flag is named mode and what should be named mode is named perm.

The name perm is used as synonym for mode in other places, so keep
it as is. Rename mode to flag to match the real meaning of the
parameter. Also, rename path to name for consistency with other
usage of the same parameter.

Change-Id: Ideed09839d80c0383584c2268afbb6cc09ffda8c
Reviewed-on: https://go-review.googlesource.com/c/go/+/619276
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

net/url: add example for JoinPath

Change-Id: Ibbd2bda7ff2ea3c782ad41f6f00ad62849a4f066
Reviewed-on: https://go-review.googlesource.com/c/go/+/618756
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>

syscall,os: move flags validation from os.OpenFile to syscall.Open

syscall.Open is the functions that maps Unix/Go flags into Windows
concepts. Part of the flag validation logic was still implemented
in os.OpenFile, move it to syscall.Open for consistency.

A nice side effect is that we don't have to translate the file name
twice in case of an access denied error.

Change-Id: I32c647a9a2a066277c78f53bacb45fb3036f6353
Reviewed-on: https://go-review.googlesource.com/c/go/+/619275
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

doc: reference language version in pre-generic spec for easier recognition

This matches the style we use for the current spec.

Change-Id: I82ad8e9994da1c74801f3c18f32f21fdd7ac355a
Reviewed-on: https://go-review.googlesource.com/c/go/+/619476
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Bypass: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>

os: handle umask comparing execute mode in verifyCopyFS

Fixes #69788

Change-Id: I43cc4c0dc3c8aa2474cba26c84714d00828de08e
Reviewed-on: https://go-review.googlesource.com/c/go/+/619176
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Bypass: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>

net/mail: add example for ParseDate

Change-Id: Id22d199ea4b0a9795dc3d9e5f7a74be13ff0cf58
Reviewed-on: https://go-review.googlesource.com/c/go/+/618755
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

cmd/compile: use call block instead of entry block for tail call expansion

The expand-calls pass assumed that tail calls were always done in the
entry block. That used to be true, but with tail calls in wrappers
(enabled by CL 578235) and libfuzzer instrumentation, that is no
longer the case. Libfuzzer instrumentation adds an IF statement to the
start of the wrapper function.

Fixes #69825

Change-Id: I9ab7133691d8235f9df128be39bff154b0b8853b
Reviewed-on: https://go-review.googlesource.com/c/go/+/619075
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@google.com>

cmd/go: place GOROOT/bin at the beginning of PATH in 'go run'

This causes programs that use 'go' as a subprocess to use the same go
command as the parent 'go run' command.

Fixes #68005

Change-Id: I937cef474bf038a925bb74fc73e5f377b03e27b7
GitHub-Last-Rev: 9986537cadb0921763cc1496a63e3806b4aac1ac
GitHub-Pull-Request: golang/go#68040
Reviewed-on: https://go-review.googlesource.com/c/go/+/593255
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>

syscall: simplify O_TRUNC handling on Windows

The current implementation of O_TRUNC in syscall.Open on Windows is
prone to TOCTOU issues, as it opens the file twice if the first open
detects that the file doesn't exist. The file could
be created in between the two open calls, leading to the creation
of a new file with the undesired readonly attribute.

This CL implements O_TRUNC by just calling CreateFile once without
taking O_TRUNCATE into account, and then using Ftruncate if O_TRUNC is
set to truncate the file.

Updates #38225.

Change-Id: Ic3ad1bab75c9a1c16f99c8c5bed867c5dbc3a23b
Reviewed-on: https://go-review.googlesource.com/c/go/+/618836
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

syscall: implement Ftruncate using a single syscall on Windows

Ftruncate can be implemented on Windows using a single syscall. This
makes the implementation more efficient and less prone to races when
used in combination with other Seek calls.

Change-Id: I5d9f780fba2710403fce89d3325e519f33ad9ae8
Reviewed-on: https://go-review.googlesource.com/c/go/+/618835
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

internal/runtime/maps: support big endian architectures

For #54766.

Cq-Include-Trybots: luci.golang.try:gotip-linux-ppc64_power10
Change-Id: I0a928c4b1e90056c50d2abca8982bdb540c33a34
Reviewed-on: https://go-review.googlesource.com/c/go/+/619035
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Pratt <mpratt@google.com>

cmd/compile, internal/runtime/atomic: add Xchg8 for arm64

For #69735

Change-Id: I61a2e561684c538eea705e60c8ebda6be3ef31a7
GitHub-Last-Rev: 3c7f4ec845182d3ef1a007319d91027433163db3
GitHub-Pull-Request: golang/go#69751
Reviewed-on: https://go-review.googlesource.com/c/go/+/617595
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

internal/runtime/maps: initial swiss table map implementation

Add a new package that will contain a new "Swiss Table"
(https://abseil.io/about/design/swisstables) map implementation, which
is intended to eventually replace the existing runtime map
implementation.

This implementation is based on the fabulous
github.com/cockroachdb/swiss package contributed by Peter Mattis.

This CL adds an hash map implementation. It supports all the core
operations, but does not have incremental growth.

For #54766.

Change-Id: I52cf371448c3817d471ddb1f5a78f3513565db41
Reviewed-on: https://go-review.googlesource.com/c/go/+/582415
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

cmd/go/internal/modload: use slices.Contains

Change-Id: I9d39984b6b15d415189592b592de471f50b43d0b
Reviewed-on: https://go-review.googlesource.com/c/go/+/618495
Reviewed-by: Michael Matloob <matloob@golang.org>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

encoding/asn1: use slices.Equal in ObjectIdentifier.Equal

Change-Id: I5efe3b9dcee85dfa34b6072c6f85108b6fc7cf99
Reviewed-on: https://go-review.googlesource.com/c/go/+/618515
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>

cmd/internal/obj: optimize the function stacksplit on loong64

In the process of stack split checking, loong64 uses the following
logic: if SP > stackguard then goto done, else morestack

The possible problem here is that the probability of morestack
execution is much lower than done, while static branch prediction
is more inclined to obtain morestack, which will cause a certain
probability of branch prediction error.

Change the logic here to:
if SP <= stackguard then goto morestack, else done

benchmarks on 3A6000:

goos: linux
goarch: loong64
pkg: fmt
cpu: Loongson-3A6000 @ 2500.00MHz
                              │  bench.old  │              bench.new              │
                              │   sec/op    │   sec/op     vs base                │
SprintfPadding                  418.3n ± 1%   387.0n ± 0%   -7.49% (p=0.000 n=20)
SprintfEmpty                    35.95n ± 0%   35.86n ± 0%   -0.25% (p=0.000 n=20)
SprintfString                   75.02n ± 1%   72.24n ± 0%   -3.71% (p=0.000 n=20)
SprintfTruncateString           165.7n ± 3%   139.9n ± 1%  -15.58% (p=0.000 n=20)
SprintfTruncateBytes            171.0n ± 0%   147.3n ± 0%  -13.83% (p=0.000 n=20)
SprintfSlowParsingPath          90.56n ± 0%   80.85n ± 0%  -10.72% (p=0.000 n=20)
SprintfQuoteString              560.2n ± 0%   509.7n ± 0%   -9.01% (p=0.000 n=20)
SprintfInt                      58.62n ± 0%   56.45n ± 0%   -3.70% (p=0.000 n=20)
SprintfIntInt                   141.7n ± 0%   122.2n ± 0%  -13.73% (p=0.000 n=20)
SprintfPrefixedInt              210.6n ± 0%   208.8n ± 0%   -0.88% (p=0.000 n=20)
SprintfFloat                    282.3n ± 0%   251.8n ± 1%  -10.80% (p=0.000 n=20)
SprintfComplex                  854.1n ± 0%   813.8n ± 0%   -4.71% (p=0.000 n=20)
SprintfBoolean                  76.32n ± 0%   71.14n ± 1%   -6.79% (p=0.000 n=20)
SprintfHexString                218.5n ± 0%   193.4n ± 0%  -11.51% (p=0.000 n=20)
SprintfHexBytes                 321.3n ± 0%   275.0n ± 0%  -14.42% (p=0.000 n=20)
SprintfBytes                    573.5n ± 0%   553.2n ± 1%   -3.54% (p=0.000 n=20)
SprintfStringer                 501.1n ± 1%   446.6n ± 0%  -10.86% (p=0.000 n=20)
SprintfStructure                1.793µ ± 0%   1.683µ ± 0%   -6.16% (p=0.000 n=20)
ManyArgs                        500.0n ± 0%   470.4n ± 0%   -5.92% (p=0.000 n=20)
FprintInt                       67.51n ± 0%   65.71n ± 0%   -2.66% (p=0.000 n=20)
FprintfBytes                    130.9n ± 0%   129.5n ± 1%   -1.11% (p=0.000 n=20)
FprintIntNoAlloc                67.55n ± 0%   65.80n ± 0%   -2.58% (p=0.000 n=20)
ScanInts                        386.3µ ± 0%   346.5µ ± 0%  -10.29% (p=0.000 n=20)
ScanRecursiveInt                25.97m ± 0%   25.93m ± 0%   -0.15% (p=0.038 n=20)
ScanRecursiveIntReaderWrapper   26.07m ± 0%   25.93m ± 0%   -0.53% (p=0.001 n=20)
geomean                         702.6n        653.7n        -6.96%

goos: linux
goarch: loong64
pkg: test/bench/go1
cpu: Loongson-3A6000 @ 2500.00MHz
                      │  bench.old   │              bench.new              │
                      │    sec/op    │   sec/op     vs base                │
BinaryTree17              7.688 ± 1%    7.724 ± 0%   +0.47% (p=0.040 n=20)
Fannkuch11                2.670 ± 0%    2.645 ± 0%   -0.94% (p=0.000 n=20)
FmtFprintfEmpty          35.93n ± 0%   37.50n ± 0%   +4.37% (p=0.000 n=20)
FmtFprintfString         56.32n ± 0%   59.74n ± 0%   +6.08% (p=0.000 n=20)
FmtFprintfInt            64.47n ± 0%   61.26n ± 0%   -4.98% (p=0.000 n=20)
FmtFprintfIntInt        100.30n ± 0%   99.67n ± 0%   -0.63% (p=0.000 n=20)
FmtFprintfPrefixedInt    116.7n ± 0%   119.3n ± 0%   +2.23% (p=0.000 n=20)
FmtFprintfFloat          234.1n ± 0%   203.4n ± 0%  -13.11% (p=0.000 n=20)
FmtManyArgs              503.0n ± 0%   467.9n ± 0%   -6.96% (p=0.000 n=20)
GobDecode                8.125m ± 0%   7.299m ± 0%  -10.17% (p=0.000 n=20)
GobEncode                8.930m ± 1%   8.581m ± 1%   -3.91% (p=0.000 n=20)
Gzip                     280.0m ± 0%   279.8m ± 0%   -0.10% (p=0.000 n=20)
Gunzip                   33.30m ± 0%   32.48m ± 0%   -2.49% (p=0.000 n=20)
HTTPClientServer         55.43µ ± 0%   54.10µ ± 1%   -2.41% (p=0.000 n=20)
JSONEncode              10.086m ± 0%   9.055m ± 0%  -10.22% (p=0.000 n=20)
JSONDecode               49.37m ± 1%   46.22m ± 1%   -6.40% (p=0.000 n=20)
Mandelbrot200            4.606m ± 0%   4.606m ± 0%        ~ (p=0.280 n=20)
GoParse                  5.010m ± 0%   4.855m ± 0%   -3.09% (p=0.000 n=20)
RegexpMatchEasy0_32      59.09n ± 0%   59.32n ± 0%   +0.39% (p=0.000 n=20)
RegexpMatchEasy0_1K      455.2n ± 0%   453.8n ± 0%   -0.31% (p=0.000 n=20)
RegexpMatchEasy1_32      59.24n ± 0%   60.11n ± 0%   +1.47% (p=0.000 n=20)
RegexpMatchEasy1_1K      555.2n ± 0%   553.9n ± 0%   -0.23% (p=0.000 n=20)
RegexpMatchMedium_32     845.7n ± 0%   775.6n ± 0%   -8.28% (p=0.000 n=20)
RegexpMatchMedium_1K     26.68µ ± 0%   26.48µ ± 0%   -0.78% (p=0.000 n=20)
RegexpMatchHard_32       1.317µ ± 0%   1.326µ ± 0%   +0.68% (p=0.000 n=20)
RegexpMatchHard_1K       41.35µ ± 0%   40.95µ ± 0%   -0.97% (p=0.000 n=20)
Revcomp                  463.0m ± 0%   473.0m ± 0%   +2.15% (p=0.000 n=20)
Template                 83.80m ± 0%   76.26m ± 1%   -9.00% (p=0.000 n=20)
TimeParse                283.3n ± 0%   260.8n ± 0%   -7.96% (p=0.000 n=20)
TimeFormat               307.2n ± 0%   290.5n ± 0%   -5.45% (p=0.000 n=20)
geomean                  53.16µ        51.67µ        -2.79%

Change-Id: Iaec2f50db18e9a2b405605f8b92af3683114ea34
Reviewed-on: https://go-review.googlesource.com/c/go/+/616035
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

net: detect EAI_ADDRFAMILY for cgo host lookup on FreeBSD

For #61095.

Change-Id: Iff9f19f6f2eada739967774b50d949f9c5893ee0
Cq-Include-Trybots: luci.golang.try:gotip-darwin-amd64_14,gotip-freebsd-amd64
Reviewed-on: https://go-review.googlesource.com/c/go/+/618015
TryBot-Bypass: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Damien Neil <dneil@google.com>

syscall, internal/syscall/unix: add Openat support for wasip1

The syscall package is mostly frozen, but wasip1 file syscall
support was added to syscall and the Open and Openat
implementations overlap. Implement Openat in syscall for
overall simplicity.

We already have syscall.Openat for some platforms, so this
doesn't add any new functions to syscall.

For #67002

Change-Id: Ia34b12ef11fc7a3b7832e07b3546a760c23efe5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/617378
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>

internal/syscall/unix: add Mkdirat and Readlinkat

For #67002

Change-Id: I460e02db33799c145c296bcf0668fa555199036e
Reviewed-on: https://go-review.googlesource.com/c/go/+/617376
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>

cmd/compile: add internal/runtime/atomic.Xchg8 intrinsic for PPC64

This is minor extension of the existing support for 32 and
64 bit types.

For #69735

Change-Id: I6828ec223951d2b692e077dc507b000ac23c32a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/617496
Reviewed-by: Rhys Hiltner <rhys.hiltner@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>

iter: fix spurious TestPullDoubleYield[2] successes

The two tests confused a nil pointer panic with the panic from a double
call to yield.

Change-Id: I0040e60cf4b702a92825d308db1201a85f164009
Reviewed-on: https://go-review.googlesource.com/c/go/+/617917
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

cmd/compile: avoid dynamic type when possible

If the expression type is a single compile-time known type, use that
type instead of the dynamic one, so the later passes of the compiler
could skip un-necessary runtime calls.

Thanks Youlin Feng for writing the original test case.

Change-Id: I3f65ab90f041474a9731338a82136c1d394c1773
Reviewed-on: https://go-review.googlesource.com/c/go/+/616975
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.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>
Reviewed-by: Cherry Mui <cherryyz@google.com>

internal/syscall/windows: add NtCreateFile

Mostly copied from x/sys/windows.

This adds a various related types and functions,
but the purpose is to give access to NtCreateFile,
which can be used as an equivalent to openat.

For #67002

Change-Id: I04e6f630445a55c2000c9c323ce8dcdc7fc0d0e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/617377
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Quim Muntal <quimmuntal@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

go/types, types2: use slices to simplify the code

Simplify the code and remove some unnecessary helper functions.

Change-Id: I1419ca3a0c7048891bbdc274f53fd72960410651
GitHub-Last-Rev: 06b1f03bb36cf1028a52f0223af81cf74ec4d77c
GitHub-Pull-Request: golang/go#68732
Reviewed-on: https://go-review.googlesource.com/c/go/+/602719
Reviewed-by: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>

io/fs: document need to call File.Close

Fixes #69723

Change-Id: Id081f68cd30abfa77a971a2370f4a0ebf330eb8d
Reviewed-on: https://go-review.googlesource.com/c/go/+/618095
Reviewed-by: Alan Donovan <adonovan@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Commit-Queue: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>

crypto/rand: skip TestAllocations if optimizations are off

Without optimizations escape analysis can't do as much.

Updates #66779

Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-noopt
Change-Id: I9ccd1b995c62427ceebd9ce5c98170dbf4a93e8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/618275
Reviewed-by: Roland Shoemaker <roland@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

os: remove t.Parallel in TestMkdirStickyUmask

The TestMkdirStickyUmask modifies the umask for testing purpose.
When run in parallel with TestCopyFS, this temporary umask change can cause TestCopyFS to create files with unintended permissions, leading to test failures.

This change removes the t.Parallel call in TestMkdirStickyUmask to prevent interference with TestCopyFS, ensuring it doesn't run concurrently with the other tests that require umask.

Fixes #69788

Change-Id: I9cf1da9f92283340ff85d2721781760a750d124c
Reviewed-on: https://go-review.googlesource.com/c/go/+/618055
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>

internal/coverage: use 128-bit FNV-1a hash instead of MD5

This change replaces the MD5 hash used to identify coverage files with a
128-bit FNV-1a hash. This change is motivated by the fact that MD5
should only be used for legacy cryptographic purposes.

The 128-bit FNV-1a hash is sufficient for the purpose of identifying
coverage files, it having the same theoretical collision resistance as
MD5, but with the added benefit of being faster to compute.

Change-Id: I7b547ce2ea784f8f4071599a10fcb512b87ee469
Reviewed-on: https://go-review.googlesource.com/c/go/+/617360
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Than McIntosh <thanm@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

runtime: overwrite startupRand instead of clearing it

AT_RANDOM is unfortunately used by libc before we run (so make sure it's
not cleared) but also is available to cgo programs after we did. It
would be unfortunate if a cgo program assumed it could use AT_RANDOM but
instead found all zeroes there.

Change-Id: I82eff34d8cf5a499b439052b7827b8ef7cabc21d
Reviewed-on: https://go-review.googlesource.com/c/go/+/608437
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>

runtime: use arc4random_buf() for readRandom

readRandom doesn't matter on Linux because of startupRand, but it does
on Windows and macOS. Windows already uses the same API as crypto/rand.
Switch macOS away from the /dev/urandom read.

Updates #68278

Cq-Include-Trybots: luci.golang.try:gotip-darwin-amd64_14
Change-Id: Ie8f105e35658a6f10ff68798d14883e3b212eb3e
Reviewed-on: https://go-review.googlesource.com/c/go/+/608436
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

crypto/rand: add randcrash=0 GODEBUG

For #66821

Change-Id: I525c308d6d6243a2bc805e819dcf40b67e52ade5
Reviewed-on: https://go-review.googlesource.com/c/go/+/608435
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>

crypto/rand: improve TestReadLoops

As suggested by Russ Cox, making sure we see all byte values doesn't
take long and is a superset of the existing test.

Change-Id: Ifc7f18ca4189c89a3d06d0408150a2464ce5e590
Reviewed-on: https://go-review.googlesource.com/c/go/+/608397
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

crypto/rand: use runtime.getRandomData on js/wasm

This mechanism ultimately calls the same JavaScript method, but being
consistent between runtime and crypto/rand lets us reuse test coverage
across them. Also, no allocations.

Cq-Include-Trybots: luci.golang.try:gotip-js-wasm
Change-Id: I035da1ed603fbcdad61945f2b57f3fb527a959fe
Reviewed-on: https://go-review.googlesource.com/c/go/+/608396
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>

crypto/rand: use arc4random_buf() on OpenBSD

OpenBSD system calls are mediated by libc anyway, and arc4random_buf()
is the preferred mechanism to obtain random bytes.

Also, rename NetBSD's function to reflect it's not actually calling
getentropy(3).

Cq-Include-Trybots: luci.golang.try:gotip-openbsd-amd64
Change-Id: Id1f3f7af16750537e2420bcf44b086de5854198c
Reviewed-on: https://go-review.googlesource.com/c/go/+/608395
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Bypass: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>

crypto/rand: reintroduce urandom fallback for legacy Linux kernels

Reintroduce the urandom fallback, but this time with a robust set of
tests all pointing guns at each other, including a seccomp'd respawn
simulating the lack of getrandom, to make sure the fallback both works
and is never hit unexpectedly.

Unlike the Go 1.23 fallback, the new one only triggers on ENOSYS (which
is cached by unix.GetRandom) and doesn't handle the EAGAIN errors we
never got an explanation for.

We still crash the program from Read if we have to go to /dev/urandom
and we fail to open it.

For #67001
Updates #66821

Tested on legacy SlowBots (without plan9 and illumos, which don't work):
TRY=aix-ppc64,dragonfly-amd64,freebsd-amd64,freebsd-386,netbsd-amd64

Cq-Include-Trybots: luci.golang.try:gotip-darwin-amd64_14,gotip-solaris-amd64,gotip-js-wasm,gotip-wasip1-wasm_wasmtime,gotip-wasip1-wasm_wazero,gotip-windows-amd64,gotip-windows-386,gotip-linux-386,gotip-linux-amd64-longtest-race,gotip-linux-amd64-boringcrypto
Change-Id: Idecc96a18cd6363087f5b2a4671c6fd1c41a3b0e
Reviewed-on: https://go-review.googlesource.com/c/go/+/608175
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

crypto/rand: prevent Read argument from escaping to heap

Mateusz had this idea before me in CL 578516, but it got much easier
after the recent cleanup.

It's unfortunate we lose the test coverage of batched, but the package
is significantly simpler than when we introduced it, so it should be
easier to review that everything does what it's supposed to do.

Fixes #66779

Co-authored-by: Mateusz Poliwczak <mpoliwczak34@gmail.com>
Change-Id: Id35f1172e678fec184efb0efae3631afac8121d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/602498
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

crypto/rand: crash program if Read would return an error

Fixes #66821
Fixes #54980

Change-Id: Ib081f4e4f75c7936fc3f5b31d3bd07cca1c2a55c
Reviewed-on: https://go-review.googlesource.com/c/go/+/602497
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>

crypto/rand: remove /dev/urandom fallback and improve getrandom batching

The fallback was reachable on

    - Linux, where starting in Go 1.24 we require a kernel with
      getrandom(2), see #67001.

    - FreeBSD, which added getrandom(2) in FreeBSD 12.0, which we
      require since Go 1.19.

    - OpenBSD, which added getentropy(2) in OpenBSD 5.6, and we only
      support the latest version.

    - DragonFly BSD, which has getrandom(2) and where we support only
      the latest version.

    - NetBSD, where we switched to kern.arandom in CL 511036, available
      since NetBSD 4.0.

    - illumos, which has getrandom(2). (Supported versions unclear.)

    - Solaris, which had getrandom(2) at least since Oracle
      Solaris 11.4.

    - AIX, which... ugh, fine, but that code is now in rand_aix.go.

At the end of the day the platform-specific code is just a global
func(b []byte) error, so simplified the package around that assumption.

This also includes the following change, which used to be a separate CL.

    crypto/rand: improve getrandom batching and retry logic

    The previous logic assumed getrandom never returned short, and then
    applied stricter-than-necessary batch size limits, presumably to
    avoid short returns.

    This was still not sufficient because above 256 bytes getrandom(2)
    can be interrupted by a signal and return short *or* it can simply
    return EINTR if the pool is not initialized (regardless of buffer
    size).

    https://man.archlinux.org/man/getrandom.2#Interruption_by_a_signal_handler

    Whether this ever failed in practice is unknown: it would have been
    masked by the /dev/urandom fallback before.

    Instead, we apply buffer size limits only where necessary (really,
    only Solaris in practice and FreeBSD in theory) and then handle
    gracefully short returns and EINTR.

    Change-Id: I8677b457aab68a8fb6137a3b43538efc62eb7c93

It turns out that we now know that large getrandom calls *did* fail in
practice, falling back on /dev/urandom, because when we removed the
fallback TestBidiStreamReverseProxy with its 4KiB read started failing.

https://cr-buildbucket.appspot.com/build/8740779846954406033

For #66821

Change-Id: Iaca62997604f326501a51401cdc2659c2790ff22
Reviewed-on: https://go-review.googlesource.com/c/go/+/602495
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Daniel McCarney <daniel@binaryparadox.net>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

cmd/go: adjust test with tricky ld flags to not run on Darwin

normally this would not run on darwin anyway, but if there
happens to be a "pkg-config" binary, then it will.  Darwin's
clang/linker does not have this flag.

Change-Id: I61929cf193c95b420441187beb8b237fa1037807
Reviewed-on: https://go-review.googlesource.com/c/go/+/616376
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Sam Thanawalla <samthanawalla@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>

runtime: use stringslite.CutPrefix in isExportedRuntime

Change-Id: I7cbbe3b9a9f08ac98e3e76be7bda2f7df9c61fb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/617915
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

cmd/cgo: avoid endless recursion on recursive type

Fixes #69176

Change-Id: I2e3b2a7cf7699697b957fc69ecf5200ebb137bc3
Reviewed-on: https://go-review.googlesource.com/c/go/+/609975
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

internal/cpu: add CPU feature LAMCAS and LAM_BH detection on loong64

Change-Id: Ic5580c4ee006d87b3152ae5de7b25fb532c6a33f
Reviewed-on: https://go-review.googlesource.com/c/go/+/612976
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Martin Möhrmann <martin@golang.org>

os: check permissions of CopyFS copied files

CopyFS stipulates the permissions of the created files,
we should test them in the unit test.

* chmod x for testdata/x to test CopyFS for executable

* check the files permissions to ensure CopyFS follows the stipulated
  convention

Change-Id: Id13a8ad920ad0c1ff4b801dec3bfa6869cb3101f
Reviewed-on: https://go-review.googlesource.com/c/go/+/616615
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

go/types, types2: always try inference over methods when possible

During type inference, when comparing type parameters against their
constraints, if a type argument is completely known it must implement
its constraint. In this case, always unify the type argument's methods
against the constraint methods, if any.

Before this CL, this step was only attempted if the constraint had no
core type. That left information unused which led to type inference
failures where it should have succeeded.

Fixes #66751.

Change-Id: I71e96b71258624212186cf17ec47e67a589817b9
Reviewed-on: https://go-review.googlesource.com/c/go/+/617896
Reviewed-by: Tim King <taking@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

go/types, types2: add additional tracing output in type inference

To support analyzing type inference failures.

Change-Id: I47882f6b634d5fcf1834923ec372313323d31a9d
Reviewed-on: https://go-review.googlesource.com/c/go/+/617895
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Tim King <taking@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>

runtime: memclrNoHeapPointers optimization for block alignment

goos: linux
goarch: arm64
pkg: runtime
               │  base.log   │               opt.log               │
               │   sec/op    │   sec/op     vs base                │
Memclr/5-4       3.378n ± 2%   3.376n ± 2%        ~ (p=0.128 n=10)
Memclr/16-4      2.749n ± 1%   2.776n ± 2%   +1.00% (p=0.001 n=10)
Memclr/64-4      4.588n ± 2%   4.184n ± 2%   -8.78% (p=0.000 n=10)
Memclr/256-4     8.758n ± 0%   7.103n ± 0%  -18.90% (p=0.000 n=10)
Memclr/4096-4    58.80n ± 0%   57.43n ± 0%   -2.33% (p=0.000 n=10)
Memclr/65536-4   868.7n ± 1%   861.7n ± 1%   -0.80% (p=0.004 n=10)
Memclr/1M-4      23.08µ ± 6%   23.55µ ± 6%        ~ (p=0.739 n=10)
Memclr/4M-4      219.6µ ± 3%   216.1µ ± 2%        ~ (p=0.123 n=10)
Memclr/8M-4      586.1µ ± 1%   586.4µ ± 2%        ~ (p=0.853 n=10)
Memclr/16M-4     1.312m ± 0%   1.311m ± 1%        ~ (p=0.481 n=10)
Memclr/64M-4     5.332m ± 1%   5.681m ± 0%   +6.55% (p=0.000 n=10)
geomean          1.723µ        1.683µ        -2.31%

Change-Id: Icad625065fb1f30b2a4094f3f1e58b4e9b3d841e
Reviewed-on: https://go-review.googlesource.com/c/go/+/616137
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>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

cmd/go: relax the regular expression of TestScript/list_pkgconfig_error

Fixes #68283

Change-Id: I63bd128bd10565ce16a13b5a60d813368db26f26
Reviewed-on: https://go-review.googlesource.com/c/go/+/616339
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

net/netip: clarify Addr.Is4In6 documentation

For #65635

Change-Id: I4e4b0309d9139f970d6fd6b41303dfd2e0ec6236
Reviewed-on: https://go-review.googlesource.com/c/go/+/617835
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

slices: print modified cloned slice in ExampleClone

Make it obvious that numbers wasn't modified, but clone was.

Change-Id: Id8bd4ca59b7348cd218faef61abfdf12e20c89f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/617795
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

Revert "runtime/pprof: make TestBlockMutexProfileInlineExpansion stricter"

This reverts commit 5b0f8596b766afae9dd1f117a4a5dcfbbf1b80f1.

Reason for revert: This CL breaks gotip-linux-amd64-noopt builder.

Change-Id: I3950211f05c90e4955c0785409b796987741a9f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/617715
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Pratt <mpratt@google.com>

go/ast/internal/tests: add missing copyright header

I have forgotten to add it in CL 616340

Change-Id: Ia4753aa20b5e2d9978c129f2ab7d063b63a5b8e2
GitHub-Last-Rev: 2a301b12df2573b1f85eece69175c109b462ab95
GitHub-Pull-Request: golang/go#69766
Reviewed-on: https://go-review.googlesource.com/c/go/+/617616
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Alan Donovan <adonovan@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

archive/tar: use hash/crc32 instead of crypto/md5 for test checksums

Using MD5 for checksums in tests is an overkill, as MD5 is designed for
cryptographic purposes. Use hash/crc32 instead, which is designed for
detecting random data corruptions, aka checksums.

Change-Id: I03b30ed7f38fba2a2e59d06bd4133b495f64a013
Reviewed-on: https://go-review.googlesource.com/c/go/+/617675
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: David Chase <drchase@google.com>

syscall: use SYS_EXIT_GROUP in CLONE_PIDFD feature check child

Inside Google we have seen issues with QEMU user mode failing to wake a
parent waitid when this child exits with SYS_EXIT. This bug appears to
not affect SYS_EXIT_GROUP.

It is currently unclear if this is a general QEMU or specific to
Google's configuration, but SYS_EXIT and SYS_EXIT_GROUP are semantically
equivalent here, so we can use the latter here in case this is a general
QEMU bug.

For #68976.

Change-Id: I34e51088c9a6b7493a060e2a719a3cc4a3d54aa0
Reviewed-on: https://go-review.googlesource.com/c/go/+/617417
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: clear isSending bit earlier

I've done some more testing of the new isSending field.
I'm not able to get more than 2 bits set. That said,
with this change it's significantly less likely to have even
2 bits set. The idea here is to clear the bit before possibly
locking the channel we are sending the value on, thus avoiding
some delay and some serialization.

For #69312

Change-Id: I8b5f167f162bbcbcbf7ea47305967f349b62b0f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/617497
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>