Go 1.19 introduce new append-like APIs in package encoding/binary, this
change teaches the inliner to treat calls to these methods as cheap, so
that code using them will be more inlineable.
Updates #42958
Change-Id: Ie3dd4906e285430f435bdedbf8a11fdffce9302d
Reviewed-on: https://go-review.googlesource.com/c/go/+/431015
Auto-Submit: Keith Randall <khr@golang.org>
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Reviewed-by: Keith Randall <khr@google.com>
These instructions already do sign extension on output, so we can get rid of it.
Note: (MOVWreg (MULW x y)) may araise from divisions by constant,
generic rules replace them with multiply and may produce (Rsh32x64 (Mul32 _ _) _).
Change-Id: I41bc9b519e38bc6027311de604dadb962cd0bbf4
Reviewed-on: https://go-review.googlesource.com/c/go/+/429757
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
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Reviewed-by: Meng Zhuo <mzh@golangcn.org>
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Reviewed-by: Jenny Rakoczy <jenny@golang.org>
Calling close is no longer necessary.
It was was originally necessary to cleanup goroutines
spawned to decompress the stream.
This has not been the case since CL 4548079.
Update the documentation to mention how it handles trailing data
after the end of the DEFLATE stream.
Change-Id: Ieacba264230560713b7b8d604665223fd096f4ec
Reviewed-on: https://go-review.googlesource.com/c/go/+/430377
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We added -pagezero_size in CL 72730, where it was intented for iOS.
The current code passes it only on macOS/AMD64 instead. It is not
really necessary there. Also, the new darwin linker starts to emit
a warning about deprecation of the flag. Stop passing it.
For #54482.
Change-Id: If9db7a1645c37d4284e48f075856912df8d8c1a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/430936
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Allow us to select a race .syso file based on subarch values.
Note that this doesn't actually change the syso used. This CL
just moves things around in preparation for adding v3-specific
versions in future CLs.
Change-Id: I14e3c273a7c6f07b13b22193b7a851ea94c765cb
Reviewed-on: https://go-review.googlesource.com/c/go/+/424034
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CL 413374 added syscall.Mmap on solaris. Use it in cmd/compile and
cmd/link if the bootstrap toolchain is Go ≥ 1.20.
For #52875
For #54265
Change-Id: I9a0534bf97926eecf0c6f1f9218e855344ba158f
Reviewed-on: https://go-review.googlesource.com/c/go/+/430496
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Support for 1xx responses has recently been merged in
net/http (CL 269997).
As discussed in this CL
(https://go-review.googlesource.com/c/go/+/269997/comments/1ff70bef_c25a829a),
support for forwarding 1xx responses in ReverseProxy has been extracted
in this separate patch.
According to RFC 7231, "a proxy MUST forward 1xx responses unless the
proxy itself requested the generation of the 1xx response".
Consequently, all received 1xx responses are automatically forwarded as long as the
underlying transport supports ClientTrace.Got1xxResponse.
Fixes#26088Fixes#51914
Change-Id: I3a35ea023b798bfe56b7fb8696d5a49695229cfd
GitHub-Last-Rev: dab8a461fb
GitHub-Pull-Request: golang/go#53164
Reviewed-on: https://go-review.googlesource.com/c/go/+/409536
Reviewed-by: Damien Neil <dneil@google.com>
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Noticed in a manual audit from a customer codebase that the pattern
w.WriteString(fmt.Sprint*(args...))
was less efficient and in most cases we can just invoke:
fmt.Fprint*(w, args...)
and from the simple benchmarks we can see quick wins in all dimensions:
$ benchstat before.txt after.txt
name old time/op new time/op delta
DetailString-8 5.48µs ±23% 4.40µs ±11% -19.79% (p=0.000 n=20+17)
name old alloc/op new alloc/op delta
DetailString-8 2.63kB ± 0% 2.11kB ± 0% -19.76% (p=0.000 n=20+20)
name old allocs/op new allocs/op delta
DetailString-8 63.0 ± 0% 50.0 ± 0% -20.63% (p=0.000 n=20+20)
Change-Id: I47a2827cd34d6b92644900b1bd5f4c0a3287bdb1
Reviewed-on: https://go-review.googlesource.com/c/go/+/429861
Reviewed-by: Robert Findley <rfindley@google.com>
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Remove an unnecessary 'an' from errorcodes.go.
Change-Id: Iabe8ce479077cbfff936d57c788a9b39d7e5b34e
Reviewed-on: https://go-review.googlesource.com/c/go/+/430495
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The existing implementation allocates a new string even when the
count is 1, where we know the output is the same as the input.
While we wouldn't expect a count of 1 for hardcoded values of the
parameter, it is expected when the parameter is computed based on
a different value (e.g., the length of a input slice).
name old time/op new time/op delta
Repeat/5x0-10 2.03ns ± 0% 2.02ns ± 0% ~ (p=1.000 n=1+1)
Repeat/5x1-10 13.7ns ± 0% 2.0ns ± 0% ~ (p=1.000 n=1+1)
Repeat/5x2-10 18.2ns ± 0% 18.1ns ± 0% ~ (p=1.000 n=1+1)
Repeat/5x6-10 27.0ns ± 0% 27.0ns ± 0% ~ (p=1.000 n=1+1)
Repeat/10x0-10 2.02ns ± 0% 2.02ns ± 0% ~ (p=1.000 n=1+1)
Repeat/10x1-10 16.1ns ± 0% 2.0ns ± 0% ~ (p=1.000 n=1+1)
Repeat/10x2-10 20.8ns ± 0% 20.9ns ± 0% ~ (p=1.000 n=1+1)
Repeat/10x6-10 29.2ns ± 0% 29.4ns ± 0% ~ (p=1.000 n=1+1)
Change-Id: I48e08e08f8f6d6914d62b3d6a61d563d637bec59
GitHub-Last-Rev: 068f58e08b
GitHub-Pull-Request: golang/go#53321
Reviewed-on: https://go-review.googlesource.com/c/go/+/411477
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These variables never change, we don't need second copies of them.
Also rename bPlusBuild to plusBuild, since it is the only remaining
variable with a "b" prefix.
Change-Id: I97089b001d23e9b0f2096e19d9ceed7a9bbb377d
Reviewed-on: https://go-review.googlesource.com/c/go/+/429636
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Reviewed-by: Ian Lance Taylor <iant@google.com>
The issue referenced in work_prune.txt was fixed in CL 362754, but we
forgot to update the TODO or mark the issue as fixed in the commit
message.
Updates #48331.
Change-Id: Id2115e496aeaef275dd3c8d32c5c5564e6addb07
Reviewed-on: https://go-review.googlesource.com/c/go/+/425485
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Fixes#52812
Change-Id: Idb70d0540bbf9ecdc64293c62a23f07ee3be883c
Reviewed-on: https://go-review.googlesource.com/c/go/+/405615
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The rule uses R25 as a scratch register. If the input is R25 it
will be clobbered on the way, causing wrong result.
Change-Id: I464eadbdef0f3a5e90f9ef8c818393baa4335b87
Reviewed-on: https://go-review.googlesource.com/c/go/+/430015
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The changes improve the documentation for DefaultTransport, making
the style with how the HTTP proxy environment variables are being
referred to, consistent with the rest of the project's
documentation.
Also mention HTTPS_PROXY environment variables, as suggested in #32649.
Change-Id: I4e6b49881d7b30b5a0d4699531fa7c2929fc49f7
GitHub-Last-Rev: 2fc751937b
GitHub-Pull-Request: golang/go#54996
Reviewed-on: https://go-review.googlesource.com/c/go/+/430135
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all_test.go is quite big, so let it contain tests only.
Change-Id: I5003db4a8b1e2384ea8470f5e89e1c26d61d10ae
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objabi.HeadType is typically used as a non-pointer type, however the String function
is declared on a pointer receiver. This means that in most cases its integer value
is printed, rather than the value from the String function.
Change-Id: I3d28d9680e88a714bc1152ed5e1df4ac43d7a33f
Reviewed-on: https://go-review.googlesource.com/c/go/+/430556
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Before committing, the test coverage of strings/builder.go is 97.4%
After committing, the test coverage of strings/builder.go is 100%
Change-Id: I22643b1c4632b5ca7ef98362f32bb85faae80bad
GitHub-Last-Rev: 2a55ca3e33
GitHub-Pull-Request: golang/go#55004
Reviewed-on: https://go-review.googlesource.com/c/go/+/430156
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If the entry symbol cannot be found (for example, a new port is being brought
up and no rt0 code has been provided), the linker will currently panic. Rather
than panicing, generate an error that aids in debugging:
missing entry symbol "_rt0_arm64_openbsd"
Change-Id: I9cc38eaab48f730d596ca7fa9e9e3d68250ae4d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/430555
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RFC 3339 is the most common time representation,
being used in an overwhelming 57.3% of all specified formats,
while the next competitor only holds 7.5% usage.
Specially optimize parsing to handle the RFC 3339 format.
To reduce the complexity of error checking,
parseRFC3339 simply returns a bool indicating parsing success.
It leaves error handling to the general parse path.
To assist in fuzzing, the internal parse function was left unmodified
so that we could test that parseRFC3339 and parse agree with each other.
Performance:
name old time/op new time/op delta
ParseRFC3339UTC 112ns ± 1% 37ns ± 1% -67.37% (p=0.000 n=9+9)
ParseRFC3339TZ 259ns ± 2% 67ns ± 1% -73.92% (p=0.000 n=10+9)
Credit goes to Amarjeet Anand for a prior CL attemping to optimize this.
See CL 425014.
Fixes#54093
Change-Id: I14f4e8c52b092d44ceef6863f261842ed7e83f4c
Reviewed-on: https://go-review.googlesource.com/c/go/+/425197
Reviewed-by: Rob Pike <r@golang.org>
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Direct syscalls should no longer be used on darwin. Instead, directly
call libc's msync when using Go ≥ 1.20 for bootstrap.
For #54265
Change-Id: Ie3f1e6ccd1a06e7f0ddd88cdef5067393a69e8db
Reviewed-on: https://go-review.googlesource.com/c/go/+/430336
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Go 1.17 is the minimum required version for bootstrap as of Go 1.20.
Also, the package no longer builds with Go 1.12 used for bootstrap.
Thus, drop the Go 1.12 compatibility and used linkname unconditionally.
For #44505
Change-Id: Ic160aba4a33d580987b4633a3db03a025804d090
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Add a new flag 'paramNames' to typeWriter struct to control whether
function parameter names are written or not (set by default). Unset
it when we want the function signature w/o parameter names, e.g. when
showing two signatures that are not identical. This makes is much
easier to see the typw differences in the error message.
To avoid needing to provide yet another (rarely used) boolean parameter
to typeString, remove that function in favor of setting the paramNames
flag explicitly. Adjust the code in errors.go that used typeString; the
resulting code is also more efficient (fewer bytes.Buffer allocations).
While at it, rename the typeWriter 'debug' field to 'tpSubscripts'
because that is what it controls.
Add test case and adjusted existing expected output for existing tests.
Fixes#54942.
Change-Id: I625eae30c403c39ce89951b8ea6214d783c92c75
Reviewed-on: https://go-review.googlesource.com/c/go/+/430416
Reviewed-by: Robert Findley <rfindley@google.com>
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Reviewed-by: Robert Griesemer <gri@google.com>
This CL adds a suitable error code to every error reporting,
matching what go/types already does.
For now, the error codes are not progagated through the API,
but eventually they will be available to clients.
Also, for now the errorcodes.go file is a 1:1 copy (with
adjusted package name) of go/types/errorcodes.go.
A subsequent CL will factor out this file.
In contrast to go/types, for errors due to incorrect Go version,
the error code is always _UnsupportedFeature. In go/types, the
error sometimes is related to the specific operation.
Change-Id: I18771bc3d00bbdbf6d705bf25f2aea3c3d977b1c
Reviewed-on: https://go-review.googlesource.com/c/go/+/429355
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CL 428780 used unsafe.Slice instead of unsafeheader for simplifiying the
code. However, it can be even simpler, since "p" is already a *uin16,
the unsafe cast is not necessary.
Change-Id: Idc492b73518637997e85c0b33f8591bd19b7929f
Reviewed-on: https://go-review.googlesource.com/c/go/+/429915
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The "&x.v" cost us 2 inline cost budget, causing extra inline cost for
the caller. By taking the fact that "v" is laid out in memory as the
first field of all atomic types, we can accessing it without addressing.
Discovering why attempting to convert sync.RWMutex.readerCount to atomic
type. RWMutex.RUnlock have the inline cost 75, with extra 7 inline cost
from Int32.Add causing it not inlinable anymore.
With this change, Int32.Add only has 5 inline cost budget, RWMutex can
use it while still be inlinable.
Change-Id: Iabe1d1bf53389b0b8b5f56b4611231b732fd9df5
Reviewed-on: https://go-review.googlesource.com/c/go/+/429766
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Change-Id: I9c4c3ada3a8f5d8d198cc42a4afc06972ee00c61
GitHub-Last-Rev: 4ed80119e3
GitHub-Pull-Request: golang/go#54916
Reviewed-on: https://go-review.googlesource.com/c/go/+/428921
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Change-Id: Ib9746cb4f27625cb22620271b280d2da242b2fba
Reviewed-on: https://go-review.googlesource.com/c/go/+/428437
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Implement CLONE_INTO_CGROUP feature, allowing to put a child in a
specified cgroup in a clean and simple way. Note that the feature only
works for cgroup v2, and requires Linux kernel 5.7 or newer.
Using the feature requires a new syscall, clone3. Currently this is the
only reason to use clone3, but the code is structured in a way so that
other cases may be easily added in the future.
Add a test case.
While at it, try to simplify the syscall calling code in
forkAndExecInChild1, which became complicated over time because:
1. It was using either rawVforkSyscall or RawSyscall6 depending on
whether CLONE_NEWUSER was set.
2. On Linux/s390, the first two arguments to clone(2) system call are
swapped (which deserved a mention in Linux ABI hall of shame). It
was worked around in rawVforkSyscall on s390, but had to be
implemented via a switch/case when using RawSyscall6, making the code
less clear.
Let's
- modify rawVforkSyscall to have two arguments (which is also required
for clone3);
- remove the arguments workaround from s390 asm, instead implementing
arguments swap in the caller (which still looks ugly but at least
it's done once and is clearly documented now);
- use rawVforkSyscall for all cases (since it is essentially similar to
RawSyscall6, except for having less parameters, not returning r2, and
saving/restoring the return address before/after syscall on 386 and
amd64).
Updates #51246.
Change-Id: Ifcd418ebead9257177338ffbcccd0bdecb94474e
Reviewed-on: https://go-review.googlesource.com/c/go/+/417695
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First, we know that Go source files almost always weigh at least a few
kilobytes, so we can kickstart the output buffer to be a reasonable size
and reduce the initial number of incremental allocations and copies when
appending bytes or strings to output.
Second, in nodeSize we use a nested printer, but we don't actually need
its printed bytes - we only need to know how many bytes it prints.
For that reason, use a throwaway buffer: the part of our output buffer
between length and capacity, as we haven't used it yet.
Third, use a sync.Pool to reuse allocated printers.
The current API doesn't allow reusing printers,
and some programs like gofmt will print many files in sequence.
Those changes combined result in a modest reduction in allocations and
CPU usage. The benchmark uses testdata/parser.go, which has just over
two thousand lines of code, which is pretty standard size-wise.
We also split the Print benchmark to cover both a medium-sized ast.File
as well as a pretty small ast.Decl node. The latter is a somewhat common
scenario in gopls, which has code actions which alter small bits of the
AST and print them back out to rewrite only a few lines in a file.
name old time/op new time/op delta
PrintFile-16 5.43ms ± 1% 4.85ms ± 3% -10.68% (p=0.000 n=9+10)
PrintDecl-16 19.1µs ± 0% 18.5µs ± 1% -3.04% (p=0.000 n=10+10)
name old speed new speed delta
PrintFile-16 9.56MB/s ± 1% 10.69MB/s ± 3% +11.81% (p=0.000 n=8+10)
PrintDecl-16 1.67MB/s ± 0% 1.73MB/s ± 1% +3.05% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
PrintFile-16 332kB ± 0% 107kB ± 2% -67.87% (p=0.000 n=10+10)
PrintDecl-16 3.92kB ± 0% 3.28kB ± 0% -16.38% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
PrintFile-16 3.45k ± 0% 2.42k ± 0% -29.90% (p=0.000 n=10+10)
PrintDecl-16 56.0 ± 0% 46.0 ± 0% -17.86% (p=0.000 n=10+10)
Change-Id: I475a3babca77532b2d51888f49710f74763d81d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/424924
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
After we deprecated reflect.{SliceHeader, StringHeader}, it is recommended
to use unsafe.{Slice, String} to replace its work. However, the compiler
and linker cannot be migrated for the time being.
As a temporary strategy, using the "internal/unsafeheader" package like
other code is the most suitable choice at present.
For #53003.
Change-Id: I69d0ef72e2d95caabd0706bbb247a719d225c758
Reviewed-on: https://go-review.googlesource.com/c/go/+/429755
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: hopehook <hopehook@golangcn.org>
