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56218 Commits

Author SHA1 Message Date
Keith Randall
6b165577fe cmd/compile: remove memequal call from string compares in more cases
Add more rules to ensure that order doesn't matter.

Add memequal 0 rule.

Try to use a constant argument to memequal when one is available.

Fixes #59684

Change-Id: I36e85ffbd949396ed700ed6e8ec2bc3ae013f5d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/485535
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-04-18 21:31:33 +00:00
Ian Lance Taylor
48a1dcb927 debug/elf: support zstd compression
Test cases added to debug/dwarf because that is where it matters in practice.

The new test binary line-gcc-zstd.elf built with

    gcc -g -no-pie -Wl,--compress-debug-sections=zstd line[12].c

using

    gcc (Debian 12.2.0-10) 12.2.0

with a development version of the GNU binutils.

Fixes #55107

Change-Id: I48507c96902e1f83a174e5647b5cc403d965b52b
Reviewed-on: https://go-review.googlesource.com/c/go/+/473256
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2023-04-18 20:34:36 +00:00
Ian Lance Taylor
73ee0fcf37 internal/zstd: new internal package for zstd decompression
This package only does zstd decompression, which is starting to
be used for ELF debug sections. If we need zstd compression we
should use github.com/klauspost/compress/zstd. But for now that
is a very large package to vendor into the standard library.

For #55107

Change-Id: I60ede735357d491be653477ed419cf5f2f0d3f71
Reviewed-on: https://go-review.googlesource.com/c/go/+/473356
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2023-04-18 20:34:13 +00:00
Ian Lance Taylor
d5514013b6 runtime: add and use pollDesc fd sequence field
It is possible for a netpoll file to be closed and for the pollDesc
to be reused while a netpoll is running. This normally only causes
spurious wakeups, but if there is an error on the old file then the
new file can be incorrectly marked as having an error.

Fix this problem on most systems by introducing an fd sequence field
and using that as a tag in a taggedPointer. The taggedPointer is
stored in epoll or kqueue or whatever is being used. If the taggedPointer
returned by the kernel has a tag that does not match the fd
sequence field, the notification is for a closed file, and we
can ignore it. We check the tag stored in the pollDesc, and we also
check the tag stored in the pollDesc.atomicInfo.

This approach does not work on 32-bit systems where the kernel
only provides a 32-bit field to hold a user value. On those systems
we continue to use the older method without the sequence protection.
This is not ideal, but it is not an issue on Linux because the kernel
provides a 64-bit field, and it is not an issue on Windows because
there are no poller errors on Windows. It is potentially an issue
on *BSD systems, but on those systems we already call fstat in newFile
in os/file_unix.go to avoid adding non-pollable files to kqueue.
So we currently don't know of any cases that will fail.

Fixes #59545

Change-Id: I9a61e20dc39b4266a7a2978fc16446567fe683ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/484837
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Orlando Labao <orlando.labao43@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Bypass: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Bypass: Ian Lance Taylor <iant@golang.org>
2023-04-18 20:22:52 +00:00
Ian Lance Taylor
d959dd97b1 runtime: change lfstack support to taggedPointer
This is a refactoring with no change in behavior, in preparation
for future netpoll work.

For #59545

Change-Id: I493c5fd0f49f31b75787f7b5b89c544bed73f64f
Reviewed-on: https://go-review.googlesource.com/c/go/+/484836
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Orlando Labao <orlando.labao43@gmail.com>
2023-04-18 20:22:50 +00:00
Michael Matloob
fd786a550a cmd/go: skip over all workspace modules in go mod verify
This was a remaining place where we made the assumption that there is
only one workspace module. So we'd only skip the first workspace
module when running go mod verify. Instead skip over the first
MainModules.Len() modules of the buildlist, which are all the main
modules.

Fixes #54372

Change-Id: Ife687c907ae4326759c43cc35f78d429d5113b19
Reviewed-on: https://go-review.googlesource.com/c/go/+/485475
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
2023-04-18 19:49:40 +00:00
Bryan C. Mills
903a25ae11 cmd/go: include internal/godebugs in TestNewReleaseRebuildsStalePackagesInGOPATH
This fixes a lingering failure on the 'longtest' builders,
introduced in CL 476280.

For #57001.

Change-Id: I18872b1bc990dd16c0b86ebc5878c0a04ce9b2d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/485897
Run-TryBot: Bryan Mills <bcmills@google.com>
Commit-Queue: Bryan Mills <bcmills@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-04-18 18:04:21 +00:00
Michael Matloob
59c2d787d3 src/internal/godebugs: add a skip for missing godebug.md
Currently android doesn't include godebug.md in its doc folder, and
TestAll in godebugs_test.go is failing because it can't open the file.
Add a skip in case the file is missing (except for linux so we can
catch the case where we stop generating the file).

Change-Id: I37a711e49a494c33bc92bf3e31cf40471ea9d5b6
Reviewed-on: https://go-review.googlesource.com/c/go/+/485795
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-04-18 16:58:25 +00:00
Michael Matloob
c9d5df0848 cmd/go: mark gocacheverify godebug as undocumented
This avoids the panic for godebugs without documentation. Perhaps we
eventually want to remove this godebug.

Change-Id: I032cdded0f3ccf6681821286e2cb6f0b90a318c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/485756
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
TryBot-Bypass: Michael Matloob <matloob@golang.org>
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
2023-04-18 16:26:40 +00:00
Michael Matloob
2c64b50d3a cmd/go: stub out gotoolchain.go for wasip1 os build tag
There's a stub for gotoolchain.go for the js build tag because js/wasm
doesn't define syscall.Exec. But there are builders that are wasm but
not js, which also don't have syscall.Exec. The wasip1 GOOS is one
example. Stub out gotoolchain.go for wasip1 also.

Change-Id: I224bb385474ad9c5d3c28a83a000f450dfb43c0d
Reviewed-on: https://go-review.googlesource.com/c/go/+/485735
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Michael Matloob <matloob@golang.org>
2023-04-18 16:04:10 +00:00
Than McIntosh
7c1ed1fa8f Revert "cmd/compile: rework marking of dead hidden closure functions"
This reverts commit http://go.dev/cl//484859

Reason for revert: causes linker errors in a number of google-internal tests.

Change-Id: I322252f784a46d2b1d447ebcdca86ce14bc0cc91
Reviewed-on: https://go-review.googlesource.com/c/go/+/485755
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
2023-04-18 16:03:22 +00:00
Archana R
56c4422770 runtime: improve index on ppc64x/power10
Rewrite index asm function to use the new power10 instruction lxvl,
stxvl or the load, store vector with length which can specify the
number of bytes to be stored in a register. This avoids the need to
create a separator mask and extra AND instructions. It also allows
us to process the tail end of the string using a lot fewer instructions
as we can load bytes of separator length directly rather than loading
16 bytes and masking out bytes that are greater than separator length
On power9 and power8 the code remains unchanged.
The performance for smaller sizes improve the most, on larger sizes
we see minimal improvement.

name          old time/op    new time/op     delta
Index/10          10.6ns ± 3%     9.8ns ± 2%   -7.20%
Index/11          11.2ns ± 4%    10.6ns ± 0%   -5.99%
Index/12          12.7ns ± 3%    11.3ns ± 0%  -11.21%
Index/13          13.5ns ± 2%    11.7ns ± 0%  -13.11%
Index/14          14.1ns ± 1%    12.0ns ± 0%  -14.43%
Index/15          14.3ns ± 2%    12.4ns ± 0%  -13.39%
Index/16          14.5ns ± 1%    12.7ns ± 0%  -12.57%
Index/17          26.7ns ± 0%    25.9ns ± 0%   -2.99%
Index/18          27.3ns ± 0%    26.4ns ± 1%   -3.35%
Index/19          35.7ns ±16%    26.1ns ± 1%  -26.87%
Index/20          29.4ns ± 0%    27.3ns ± 1%   -7.06%
Index/21          29.3ns ± 0%    26.9ns ± 1%   -8.37%
Index/22          30.0ns ± 0%    27.4ns ± 0%   -8.68%
Index/23          29.9ns ± 0%    27.7ns ± 0%   -7.15%
Index/24          31.0ns ± 0%    28.0ns ± 0%   -9.92%
Index/25          31.7ns ± 0%    28.4ns ± 0%  -10.54%
Index/26          30.6ns ± 0%    28.9ns ± 1%   -5.67%
Index/27          31.4ns ± 0%    29.3ns ± 0%   -6.71%
Index/28          32.7ns ± 0%    29.6ns ± 1%   -9.36%
Index/29          33.3ns ± 0%    30.1ns ± 1%   -9.70%
Index/30          32.4ns ± 0%    30.7ns ± 0%   -5.23%
Index/31          33.2ns ± 0%    30.6ns ± 1%   -7.83%
Index/32          34.3ns ± 0%    30.9ns ± 0%   -9.94%
Index/64          46.8ns ± 0%    44.2ns ± 0%   -5.66%
Index/128         71.2ns ± 0%    67.3ns ± 0%   -5.43%
Index/256          129ns ± 0%     127ns ± 0%   -1.67%
Index/2K           838ns ± 0%     804ns ± 0%   -4.03%
Index/4K          1.65µs ± 0%    1.58µs ± 0%   -4.25%
Index/2M           829µs ± 0%     793µs ± 0%   -4.42%
Index/4M          1.65ms ± 0%    1.59ms ± 0%   -4.19%
Index/64M         26.5ms ± 0%    25.4ms ± 0%   -4.18%
IndexHard2         412µs ± 0%     396µs ± 0%   -3.76%
IndexEasy/10      10.0ns ± 0%     9.3ns ± 1%   -7.20%
IndexEasy/11      10.8ns ± 1%    11.0ns ± 1%   +2.22%
IndexEasy/12      12.3ns ± 2%    11.5ns ± 1%   -6.37%
IndexEasy/13      13.1ns ± 0%    11.7ns ± 2%  -10.83%
IndexEasy/14      13.8ns ± 2%    11.9ns ± 1%  -13.52%
IndexEasy/15      14.0ns ± 2%    12.4ns ± 2%  -11.46%
IndexEasy/16      14.3ns ± 1%    12.5ns ± 0%  -12.40%
CountHard2         415µs ± 0%     396µs ± 0%   -4.48%

Change-Id: Id3efa5ed9c662a29f58125c7f866a09f29a59b6c
Reviewed-on: https://go-review.googlesource.com/c/go/+/478918
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
Run-TryBot: Archana Ravindar <aravind5@in.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
2023-04-18 15:42:18 +00:00
Brad Fitzpatrick
e875cbd9aa syscall: add a sync.Pool for a NetlinkRIB scratch buffer
The syscall.NetlinkRIB signature means it necessarily allocates but
this changes makes it allocate a bit less. For example, in the net
package:

    name                           old time/op    new time/op    delta
    Interfaces-8                     59.1µs ± 3%    57.3µs ± 2%   -3.02%  (p=0.000 n=10+10)
    InterfaceByIndex-8               53.1µs ± 5%    50.6µs ± 2%   -4.81%  (p=0.000 n=10+10)
    InterfaceByName-8                59.3µs ± 2%    57.4µs ± 1%   -3.29%  (p=0.000 n=10+10)
    InterfaceAddrs-8                  105µs ± 1%     101µs ± 1%   -4.22%  (p=0.000 n=10+9)
    InterfacesAndAddrs-8             38.2µs ± 3%    36.3µs ± 2%   -4.98%  (p=0.000 n=10+10)
    InterfacesAndMulticastAddrs-8     152µs ± 2%     154µs ± 6%     ~     (p=0.105 n=10+10)

    name                           old alloc/op   new alloc/op   delta
    Interfaces-8                     22.8kB ± 0%    18.7kB ± 0%  -17.90%  (p=0.000 n=10+9)
    InterfaceByIndex-8               16.2kB ± 0%    12.1kB ± 0%  -25.22%  (p=0.000 n=10+10)
    InterfaceByName-8                22.8kB ± 0%    18.8kB ± 0%  -17.85%  (p=0.000 n=10+10)
    InterfaceAddrs-8                 36.6kB ± 0%    28.5kB ± 0%  -22.28%  (p=0.000 n=10+10)
    InterfacesAndAddrs-8             9.60kB ± 0%    5.51kB ± 0%  -42.59%  (p=0.000 n=10+7)
    InterfacesAndMulticastAddrs-8     141kB ± 0%     141kB ± 0%     ~     (all equal)

    name                           old allocs/op  new allocs/op  delta
    Interfaces-8                       53.0 ± 0%      52.0 ± 0%   -1.89%  (p=0.000 n=10+10)
    InterfaceByIndex-8                 28.0 ± 0%      27.0 ± 0%   -3.57%  (p=0.000 n=10+10)
    InterfaceByName-8                  54.0 ± 0%      53.0 ± 0%   -1.85%  (p=0.000 n=10+10)
    InterfaceAddrs-8                    155 ± 0%       153 ± 0%   -1.29%  (p=0.000 n=10+10)
    InterfacesAndAddrs-8               38.0 ± 0%      37.0 ± 0%   -2.63%  (p=0.000 n=10+10)
    InterfacesAndMulticastAddrs-8      77.0 ± 0%      77.0 ± 0%     ~     (all equal)

Signed-off-by: Brad Fitzpatrick <bradfitz@golang.org>
Change-Id: Ic3278b2c000af78d7ed816645463c3b7ff0c90ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/485455
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
2023-04-18 14:42:52 +00:00
Matthieu Baerts
fd8acb5d4a net: mptcp: add TCPConn's MultipathTCP checker
This new TCPConn method returns whether the connection is using MPTCP or
if a fallback to TCP has been done, e.g. because the other peer doesn't
support MPTCP.

When working on the new E2E test linked to MPTCP (#56539), it looks like
the user might need to know such info to be able to do some special
actions (report, stop, etc.). This also improves the test to make sure
MPTCP has been used as expected.

Regarding the implementation, from kernel version 5.16, it is possible
to use:

    getsockopt(..., SOL_MPTCP, MPTCP_INFO, ...)

and check if EOPNOTSUPP (IPv4) or ENOPROTOOPT (IPv6) is returned. If it
is, it means a fallback to TCP has been done. See this link for more
details:

    https://github.com/multipath-tcp/mptcp_net-next/issues/294

Before v5.16, there is no other simple way, from the userspace, to check
if the created socket did a fallback to TCP. Netlink requests could be
done to try to find more details about a specific socket but that seems
quite a heavy machinery. Instead, only the protocol is checked on older
kernels.

The E2E test has been modified to check that the MPTCP connection didn't
do any fallback to TCP, explicitely validating the two methods
(SO_PROTOCOL and MPTCP_INFO) if it is supported by the host.

This work has been co-developed by Gregory Detal
<gregory.detal@tessares.net> and Benjamin Hesmans
<benjamin.hesmans@tessares.net>.

Fixes #59166

Change-Id: I5a313207146f71c66c349aa8588a2525179dd8b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/471140
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
2023-04-18 13:48:22 +00:00
Matthieu Baerts
5a34790d6d internal/poll: add GetsockoptInt
This new function wraps the getsockopt network call with an integer
argument, similar to SetsockoptInt.

This will be used in MPTCP in the following commit.

This work has been co-developed by Gregory Detal
<gregory.detal@tessares.net>.

Updates #59166

Change-Id: I8f6aa00ea2535683d9bbf436993c23e9c6ca2af3
Reviewed-on: https://go-review.googlesource.com/c/go/+/471139
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
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2023-04-18 13:44:49 +00:00
Oleksandr Redko
5e03a9c4b2 plugin: fix duplicated word in comment
Change-Id: Ia3174d079e84cf874c2f2f3093a7c6337af32b02
Reviewed-on: https://go-review.googlesource.com/c/go/+/485015
Run-TryBot: Ian Lance Taylor <iant@google.com>
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2023-04-18 13:43:02 +00:00
jiahua wang
b07b00565b maps: replace slicesEqual with slices.Equal
Change-Id: I15aeef9c6d3ddc80644a14d6266d21a8515ede4e
Reviewed-on: https://go-review.googlesource.com/c/go/+/483156
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
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2023-04-18 13:37:52 +00:00
Russ Cox
14ab998f95 cmd/go: add check for unknown godebug setting
A //go:debug line mentioning an unknown or retired setting
should be diagnosed as making the program invalid. Do that.
We agreed on this in the proposal but I forgot to implement it.

Change-Id: Ie69072a1682d4eeb6866c02adbbb426f608567c4
Reviewed-on: https://go-review.googlesource.com/c/go/+/476280
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
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2023-04-18 13:19:19 +00:00
Russ Cox
44e51e60ac cmd/go: change toolchain based on $GOTOOLCHAIN
For proposal #57001, add code to reinvoke a different Go toolchain
based on $GOTOOLCHAIN. The toolchain is searched for in $PATH
first and otherwise downloaded. The download is a standard module
download, so the toolchain is validated using the checksum database
before being executed or even stored in the file system.

Followup CLs will refine the exact toolchain selection and implement
other parts of the proposal. This is only the download+reinvoke code.

For #57001.

Change-Id: I44363cbd916dac01342b1bfce6a487fe7166be4a
Reviewed-on: https://go-review.googlesource.com/c/go/+/475955
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
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2023-04-18 13:19:02 +00:00
Michael Knyszek
ce10e9d845 Revert "cmd/compile: allow more inlining of functions that construct closures"
This reverts commit f8162a0e72.

Reason for revert: https://github.com/golang/go/issues/59680

Change-Id: I91821c691a2d019ff0ad5b69509e32f3d56b8f67
Reviewed-on: https://go-review.googlesource.com/c/go/+/485498
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
2023-04-17 21:45:00 +00:00
Michael Pratt
94850c6f79 Revert "runtime/cgo: store M for C-created thread in pthread key"
This reverts CL 481061.

Reason for revert: When built with C TSAN, x_cgo_getstackbound triggers
race detection on `g->stacklo` because the synchronization is in Go,
which isn't instrumented.

For #51676.
For #59294.
For #59678.

Change-Id: I38afcda9fcffd6537582a39a5214bc23dc147d47
Reviewed-on: https://go-review.googlesource.com/c/go/+/485275
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Reviewed-by: Than McIntosh <thanm@google.com>
2023-04-17 18:47:08 +00:00
Michael Pratt
97e5ca6d4e Revert "runtime: correct GoCheckBindM's C declaration in EnsureBindM test"
This reverts CL 482975.

Reason for revert: CL 481061 causes C TSAN failures and must be
reverted. See CL 485275. This CL depends on CL 481061.

For #59678.

Change-Id: I4599e93d536149bcec94a5a1542533107699514f
Reviewed-on: https://go-review.googlesource.com/c/go/+/485317
Reviewed-by: Than McIntosh <thanm@google.com>
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2023-04-17 18:46:31 +00:00
Michael Pratt
2068d5658e Revert "Revert "Revert "runtime: consolidate function descriptor definitions on PPC64"""
This reverts CL 481075 (a re-apply of previously reverted CL 478917).

Reason for revert: CL 481061 causes C TSAN failures and must be
reverted. See CL 485275. This CL depends on CL 481061.

For #59678.

Change-Id: I4bf7f43d9df1ae28e04cd4065552bcbee82ef13f
Reviewed-on: https://go-review.googlesource.com/c/go/+/485316
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2023-04-17 18:44:00 +00:00
Michael Pratt
0e9b2bc39a Revert "runtime/cgo: use pthread_attr_get_np on Illumos"
This reverts CL 481795.

Reason for revert: CL 481061 causes C TSAN failures and must be
reverted. See CL 485275. This CL depends on CL 481061.

For #59678.

Change-Id: I5ec1f495154205ebdf19cd44c6e6452a7a3606f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/485315
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2023-04-17 18:43:56 +00:00
Than McIntosh
f8162a0e72 cmd/compile: allow more inlining of functions that construct closures
[This is a roll-forward of CL 479095, which was reverted due to a bad
interaction between inlining and escape analysis, then later fixed
fist with an attempt in CL 482355, then again in 484859 .]

Currently, when the inliner is determining if a function is
inlineable, it descends into the bodies of closures constructed by
that function. This has several unfortunate consequences:

- If the closure contains a disallowed operation (e.g., a defer), then
  the outer function can't be inlined. It makes sense that the
  *closure* can't be inlined in this case, but it doesn't make sense
  to punish the function that constructs the closure.

- The hairiness of the closure counts against the inlining budget of
  the outer function. Since we currently copy the closure body when
  inlining the outer function, this makes sense from the perspective
  of export data size and binary size, but ultimately doesn't make
  much sense from the perspective of what should be inlineable.

- Since the inliner walks into every closure created by an outer
  function in addition to starting a walk at every closure, this adds
  an n^2 factor to inlinability analysis.

This CL simply drops this behavior.

In std, this makes 57 more functions inlinable, and disallows inlining
for 10 (due to the basic instability of our bottom-up inlining
approach), for an net increase of 47 inlinable functions (+0.6%).

This will help significantly with the performance of the functions to
be added for #56102, which have a somewhat complicated nesting of
closures with a performance-critical fast path.

The downside of this seems to be a potential increase in export data
and text size, but the practical impact of this seems to be
negligible:

	       │    before    │           after            │
	       │    bytes     │    bytes      vs base      │
Go/binary        15.12Mi ± 0%   15.14Mi ± 0%  +0.16% (n=1)
Go/text          5.220Mi ± 0%   5.237Mi ± 0%  +0.32% (n=1)
Compile/binary   22.92Mi ± 0%   22.94Mi ± 0%  +0.07% (n=1)
Compile/text     8.428Mi ± 0%   8.435Mi ± 0%  +0.08% (n=1)

Updates #56102.

Change-Id: I6e938d596992ffb473cf51e7e598f372ce08deb0
Reviewed-on: https://go-review.googlesource.com/c/go/+/484860
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2023-04-17 14:52:41 +00:00
Than McIntosh
d240226fe5 cmd/compile: rework marking of dead hidden closure functions
This patch generalizes the code in the inliner that marks unreferenced
hidden closure functions as dead. Rather than doing the marking on the
fly (previous approach), this new approach does a single pass at the
end of inlining, which catches more dead functions.

Fixes #59638.
Updates #59404.
Updates #59547.

Change-Id: I54fd63e9e37c9123b08a3e7def7d1989919bba91
Reviewed-on: https://go-review.googlesource.com/c/go/+/484859
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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2023-04-17 14:52:32 +00:00
Robert Griesemer
57678d5e03 go/types, types2: factor out type parameter renaming from type inference
Preparation for reverse type inference where there is no need
to rename all type parameters supplied to type inference when
passing generic functions as arguments to (possibly generic)
function calls.

This also leads to a better separation of concerns.

Change-Id: Id487a5c1340b743519b9053edc43f8aa99408522
Reviewed-on: https://go-review.googlesource.com/c/go/+/484655
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2023-04-17 14:01:19 +00:00
Brad Fitzpatrick
d259a50d15 cmd/go/internal/cache: update docs on cache accessor func
Its docs went stale in Go 1.12 when the build cache became required.

Signed-off-by: Brad Fitzpatrick <bradfitz@golang.org>
Change-Id: Icb7b06dc5147a858f00460e7cfe85b79b6b6f0eb
Reviewed-on: https://go-review.googlesource.com/c/go/+/465555
Reviewed-by: David Chase <drchase@google.com>
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2023-04-17 13:45:35 +00:00
Cuong Manh Le
25bc96dbd2 cmd/compile: remove typecheck.EvalConst
types2 has already done most of the constant folding parts. The only
case left is unsafe.{Alignoff,Offsetof,Sizeof} with variable size
argument, which is handled separately during typecheck.

Change-Id: I8050b7613a16b19b91751726ac07253333177f73
Reviewed-on: https://go-review.googlesource.com/c/go/+/469595
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2023-04-17 13:44:43 +00:00
Robert Griesemer
13f0b8f421 go/types, types2: (slightly) refactor tpWalker.isParameterized (cleanup)
Match the structure of cycleFinder. Removes a TODO.

Change-Id: Iec0abfc809cd522f64db8900a1f8a70cbba504ee
Reviewed-on: https://go-review.googlesource.com/c/go/+/484615
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2023-04-17 13:22:51 +00:00
Cuong Manh Le
0853f8caec cmd/compile: add test that non-name call does not allocate
Updates #57434

Change-Id: Ib90c228f95c3d61204e60f63d7de55884d839e05
Reviewed-on: https://go-review.googlesource.com/c/go/+/459496
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2023-04-14 20:24:18 +00:00
Tobias Klauser
5da1f41513 embed/internal/embedtest: test openFile.ReadAt with non-zero offset
Also fix log messages to report expected values in the standard "got foo,
want bar" format.

Change-Id: I6a9fd4abe1f86c2651c72c2bf7ac4588028e5923
Reviewed-on: https://go-review.googlesource.com/c/go/+/484715
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2023-04-14 20:10:16 +00:00
Bryan C. Mills
750e91152b cmd/compile/internal/importer,go/internal/gcimporter: use the 'go' command from build.Default.GOROOT in lookupGorootExport
Also set GOROOT explicitly in case it is set to something else in the
caller's environment.

Fixes #59598.

Change-Id: I5599ed1183b23187fc3b976786f3c320d42ef4f3
Reviewed-on: https://go-review.googlesource.com/c/go/+/484756
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2023-04-14 20:09:13 +00:00
Joel Sing
dd53a43920 cmd/link/internal/ld: disable execute-only for external linking on openbsd/arm64
The Go arm64 assembler places constants into the text section of a binary.
OpenBSD 7.3 enabled xonly by default on OpenBSD/arm64. This means that any
externally linked Go binary now segfaults. Disable execute-only when invoking
the external linker on openbsd/arm64, in order to work around this issue.

Updates #59615

Change-Id: I1a291293da3c6e4409b21873d066ea15e9bfe280
Reviewed-on: https://go-review.googlesource.com/c/go/+/484555
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2023-04-14 19:17:15 +00:00
Rob Findley
35ec948de7 go/types,types2: fix panic in reverse type inference when -lang<go1.18
Due to reverse type inference, we may not have an index expression when
type-checking a function instantiation. Fix a panic when the index expr
is nil.

Fixes #59639

Change-Id: Ib5de5e49cdb7b339653e4fb775bf5c5fdb3c6907
Reviewed-on: https://go-review.googlesource.com/c/go/+/484757
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2023-04-14 18:40:36 +00:00
Joel Sing
7c2550b7bb cmd/compile: add math benchmarks
This adds benchmarks for division and modulus of 64 bit signed and unsigned
integers.

Updates #59089

Change-Id: Ie757c6d74a1f355873e79619eae26ece21a8f23e
Reviewed-on: https://go-review.googlesource.com/c/go/+/482656
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2023-04-14 18:30:08 +00:00
Cuong Manh Le
4c20c0a826 cmd/compile/internal/ir: remove HasBreak field of some nodes
CL 484435 removed all usages of them.

Change-Id: I00f21640c7573921472ff3f88cfa92837dc3f9ad
Reviewed-on: https://go-review.googlesource.com/c/go/+/484436
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2023-04-14 17:58:29 +00:00
Cuong Manh Le
9fab498ab1 cmd/compile/internal/typecheck: remove some un-used functions
CL 405094 removed the only caller of markBreak/setHasBreak and
isTermNodes/isTermNode.

importlist variable is only used in old frontend.

Change-Id: I9472f2c0017b6200847999f2cea0e9021a1b14e2
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2023-04-14 17:58:21 +00:00
Cuong Manh Le
70451004bd cmd/compile: stop constructing untyped nodes when instrumenting asan
The code is using typecheck.ConvNop to convert from untyped int to
uintptr. However, that left the literal node untyped. It often does not
matter, because typecheck.EvalConst will see the OCONVNOP, and replace
the node with a new constant node.

This CL changes the code to construct the constant node directly using
typecheck.DefaultLit, so the last dependecy of typecheck.EvalConst will
go away, next CL can safely remove it from the code base.

Change-Id: Ie5a3d1ff6d3b72be7b8c43170eaa4f6cbb3206fc
Reviewed-on: https://go-review.googlesource.com/c/go/+/484317
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2023-04-14 17:58:12 +00:00
Cuong Manh Le
74b52d9519 cmd/compile: better code generation for constant-fold switch
CL 399694 added constant-fold switch early in compilation. So function:

func f() string {
    switch intSize {
    case 32:
        return "32"
    case 64:
        return "64"
    default:
        panic("unreachable")
    }
}

will be constant-fold to:

func f() string {
    switch intSize {
    case 64:
        return "64"
    }
}

When this function get inlined, there is a check whether we can delay
declaring the result parameter until the "return" statement. For the
original function, we can't delay the result, because there's more than
one return statement. However, the constant-fold one can, because
there's on one return statement in the body now. The result parameter
~R0 ends up declaring inside the switch statement scope.

Now, when walking the switch statement, it's re-written into if-else
statement. Without typecheck.EvalConst, the if condition "if 64 == 64"
is passed as-is to the ssa generation pass. Because "64 == 64" is not a
constant, the ssagen creates normal blocks for branching the results.
This confuses the liveness analysis, because ~R0 is only live inside the
if block. With typecheck.EvalConst, "64 == 64" is evaluated to "true",
so ssagen can branch the result without emitting conditional blocks.

Instead, the constant-fold can be re-written as:

switch {
case true:
    // Body
}

So it does not depend on the delay results check during inlining. Adding
a test, which will fail when typecheck.EvalConst is removed, so we can
do the cleanup without breaking things.

Change-Id: I638730bb147140de84260653741431b807ff2f15
Reviewed-on: https://go-review.googlesource.com/c/go/+/484316
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2023-04-14 17:58:01 +00:00
Cuong Manh Le
47e2d7495f cmd/compile: move unsafe operation out of EvalConst
So future CLs can get rid of EvalConst entirely.

Change-Id: Ic8e147fd76e53c002a6ceda2fb3be979459bf865
Reviewed-on: https://go-review.googlesource.com/c/go/+/484315
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2023-04-14 17:57:49 +00:00
Cuong Manh Le
20c349e534 cmd/compile: reenable inline static init
Updates #58293
Updates #58339
Fixes #58439

Change-Id: I06d2d92f86fa4a672d69515c4066d69d3e0fc75b
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2023-04-14 17:57:36 +00:00
Cuong Manh Le
a141c58c85 cmd/compile: handle string concatenation in static init inliner
Static init inliner is using typecheck.EvalConst to handle string
concatenation expressions. But static init inliner may reveal constant
expressions after substitution, and the compiler needs to evaluate those
expressions in non-constant semantic. Using typecheck.EvalConst, which
always evaluates expressions in constant semantic, is not the right
choice.

For safety, this CL fold the logic to handle string concatenation to
static init inliner, so there won't be regression in handling constant
expressions in non-constant semantic. And also, future CL can simplify
typecheck.EvalConst logic.

Updates #58293
Updates #58339
Fixes #58439

Change-Id: I74068d99c245938e576afe9460cbd2b39677bbff
Reviewed-on: https://go-review.googlesource.com/c/go/+/466277
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2023-04-14 17:57:14 +00:00
Bryan C. Mills
ac9d777caf path/filepath,cmd/go: skip tests involving double-symlinks on ios
For #59586.

Change-Id: I092f7a4abce1074b8eef64a3ecf9fc187914709b
Reviewed-on: https://go-review.googlesource.com/c/go/+/484755
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2023-04-14 17:01:07 +00:00
Keith Randall
2b92c39fe0 cmd/link: establish dependable package initialization order
(This is a retry of CL 462035 which was reverted at 474976.
The only change from that CL is the aix fix SRODATA->SNOPTRDATA
at inittask.go:141)

As described here:

https://github.com/golang/go/issues/31636#issuecomment-493271830

"Find the lexically earliest package that is not initialized yet,
but has had all its dependencies initialized, initialize that package,
 and repeat."

Simplify the runtime a bit, by just computing the ordering required
in the linker and giving a list to the runtime.

Update #31636
Fixes #57411

RELNOTE=yes

Change-Id: I28c09451d6aa677d7394c179d23c2c02c503fc56
Reviewed-on: https://go-review.googlesource.com/c/go/+/478916
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Reviewed-by: Cherry Mui <cherryyz@google.com>
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2023-04-14 16:55:22 +00:00
Daniel Martí
d4bcfe4e83 regexp: fix copy-paste typo on Regexp.UnmarshalText doc
I noticed that https://go.dev/cl/479401 called both methods MarshalText
in the godoc, so fix that.

While here, add more godoc links for better usability.

Change-Id: I8f10bafeca6a1ca1c1ed9be7a7dd9fdecfe991a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/484335
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2023-04-14 16:28:44 +00:00
Russ Cox
4bd20ec884 cmd/go: make go line declare minimum required Go version
For #57001, enforce the go line as declaring the minimum required
version of Go that can compile a module.

Modules that maintain compatibility with old versions of Go
but want to make use of new features in //go:build-constrained files
will be able to do so: the //go:build constraint will be interpreted
as changing the minimum Go version for that file and will unlock
the Go features allowed in that version.

Change-Id: Ibeeb7c93ce7ea2e5187d78af0757cbfac19484a0
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2023-04-14 16:08:34 +00:00
Russ Cox
804d786a30 go/types, cmd/compile/internal/types2: use per-file Go version
For #57001, compilers and others tools will need to understand that
a different Go version can be used in different files in a program,
according to the //go:build lines in those files.

Update go/types and cmd/compile/internal/types2 to track and
use per-file Go versions. The two must be updated together because
of the files in go/types that are generated from files in types2.

The effect of the //go:build go1.N line depends on the Go version
declared in the 'go 1.M' line in go.mod. If N > M, the file gets go1.N
semantics when built with a Go 1.N or later toolchain
(when built with an earlier toolchain the //go:build line will keep
the file from being built at all).
If N < M, then in general we want the file to get go1.N semantics
as well, meaning later features are disabled. However, older Go 1.M
did not apply this kind of downgrade, so for compatibility, N < M
only has an effect when M >= 21, meaning when using semantics
from Go 1.21 or later.

For #59033.

Change-Id: I93cf07e6c687d37bd37a9461dc60cc032bafd01d
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2023-04-14 16:08:31 +00:00
Than McIntosh
8854be4180 Revert "cmd/compile: allow more inlining of functions that construct closures"
This reverts commit http://go.dev/cl/c/482356.

Reason for revert: Reverting this change again, since it is causing additional failures in google-internal testing.

Change-Id: I9234946f62e5bb18c2f873a65e8b298d04af0809
Reviewed-on: https://go-review.googlesource.com/c/go/+/484735
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2023-04-14 14:45:59 +00:00
Daniel Frederick Crisman
e7b04a3e16 doc: correct spelling on placeholder
"placeholder" (no space) is already used in the spec and seems to be
the preferred option.

Removed space from "place holder".

Change-Id: I9b98f62f0e3f5adb019b99f5271cc9d19abf505e
GitHub-Last-Rev: ed5aaf9d02
GitHub-Pull-Request: golang/go#59626
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TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2023-04-13 23:15:09 +00:00