Running 'go fix' on the cmd+std packages handled much of this change.
Also update code generators to use only the new go:build lines,
not the old +build ones.
For #41184.
For #60268.
Change-Id: If35532abe3012e7357b02c79d5992ff5ac37ca23
Cq-Include-Trybots: luci.golang.try:gotip-linux-386-longtest,gotip-linux-amd64-longtest,gotip-windows-amd64-longtest
Reviewed-on: https://go-review.googlesource.com/c/go/+/536237
Reviewed-by: Ian Lance Taylor <iant@google.com>
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Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
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Change-Id: I4a6c2ef6fd21355952ab7d8eaad883646a95d364
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Change-Id: Id2079f7012392dea8dfe2386bb9fb1ea3f487a4a
Reviewed-on: https://go-review.googlesource.com/c/go/+/526015
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Auto-Submit: Ian Lance Taylor <iant@google.com>
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Use ^ and $ in the -run flag regular expression value when the intention
is to invoke a single named test. This removes the reliance on there not
being another similarly named test to achieve the intended result.
In particular, package syscall has tests named TestUnshareMountNameSpace
and TestUnshareMountNameSpaceChroot that both trigger themselves setting
GO_WANT_HELPER_PROCESS=1 to run alternate code in a helper process. As a
consequence of overlap in their test names, the former was inadvertently
triggering one too many helpers.
Spotted while reviewing CL 525196. Apply the same change in other places
to make it easier for code readers to see that said tests aren't running
extraneous tests. The unlikely cases of -run=TestSomething intentionally
being used to run all tests that have the TestSomething substring in the
name can be better written as -run=^.*TestSomething.*$ or with a comment
so it is clear it wasn't an oversight.
Change-Id: Iba208aba3998acdbf8c6708e5d23ab88938bfc1e
Reviewed-on: https://go-review.googlesource.com/c/go/+/524948
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
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Reviewed-by: Kirill Kolyshkin <kolyshkin@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Change-Id: I71a38dd20bfaf2b1aed18892d54eeb017d3d7d66
GitHub-Last-Rev: 8da43b2cbd
GitHub-Pull-Request: golang/go#61955
Reviewed-on: https://go-review.googlesource.com/c/go/+/518595
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Change-Id: I9e95806116a8547ec782f66226d1b1382c6156de
Change-Id: I9e95806116a8547ec782f66226d1b1382c6156de
GitHub-Last-Rev: 5b4ce994c1
GitHub-Pull-Request: golang/go#61829
Reviewed-on: https://go-review.googlesource.com/c/go/+/516895
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Currently on s390x, tan assembly implementation is not handling huge arguments at all. This change is to check for large arguments and revert back to native go implantation from assembly code in case of huge arguments.
The changes are implemented in assembly code to get better performance over native go implementation.
Benchmark details of tan function with table driven inputs are updated as part of the issue link.
Fixes#37854
Change-Id: I4e5321e65c27b7ce8c497fc9d3991ca8604753d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/470595
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Run-TryBot: Keith Randall <khr@golang.org>
Sin/Tan are odd, Cos is even, so it is easy to compute the correct
result from the positive argument case.
Change-Id: If851d00fc7f515ece8199cf56d21186ced51e94f
Reviewed-on: https://go-review.googlesource.com/c/go/+/509815
Run-TryBot: Keith Randall <khr@golang.org>
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Reviewed-by: Keith Randall <khr@google.com>
Adds a test that triggers the RISC-V fused multiply-add code
generation bug fixed by CL 506575.
Change-Id: Ia3a55a68b48c5cc6beac4e5235975dea31f3faf2
Reviewed-on: https://go-review.googlesource.com/c/go/+/507035
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When x*y == -z the portable implementation of FMA copied the sign
bit from x*y into the result. This meant that when x*y == -z and
x*y < 0 the result was -0 which is incorrect.
Fixes#61130.
Change-Id: Ib93a568b7bdb9031e2aedfa1bdfa9bddde90851d
Reviewed-on: https://go-review.googlesource.com/c/go/+/507376
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For #59488Fixes#60616
Change-Id: Idf9f42d7d868999664652dd7b478684a474f1d96
Reviewed-on: https://go-review.googlesource.com/c/go/+/501355
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
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Fix spelling errors discovered using https://github.com/codespell-project/codespell. Errors in data files and vendored packages are ignored.
Change-Id: I83c7818222f2eea69afbd270c15b7897678131dc
GitHub-Last-Rev: 3491615b1b
GitHub-Pull-Request: golang/go#60758
Reviewed-on: https://go-review.googlesource.com/c/go/+/502576
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There are some symbol mismatches in the comments, this commit attempts to fix them
Change-Id: I5c9075e5218defe9233c075744d243b26ff68496
Reviewed-on: https://go-review.googlesource.com/c/go/+/492996
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The "To" prefix was a relic of the first draft
that I failed to make consistent with the unprefixed
name used in the proposal. Fortunately iant spotted
it during the API audit.
Updates #56984
Updates #60560
Change-Id: Ifa6eeddf6dd5f0637c0568e383f9a4bef88b10f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/500116
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This reverts CL 467515. Now that we have cmp.Compare,
we don't need math.Compare or math.Compare32 after all.
For #56491Fixes#60519
Change-Id: I8ed33464adfc6d69bd6b328edb26aa2ee3d234d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/499416
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Eli Bendersky <eliben@google.com>
b.ResetTimer used to also stop the timer, however it does not anymore.
These benchmarks hadn't been fixed and as a result ended up measuring
some additional things.
Also, make some for loops more conventional.
Change-Id: I76ca68456d85eec51722a80587e5b2c9f5d836a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/496996
Run-TryBot: Damien Neil <dneil@google.com>
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Auto-Submit: Damien Neil <dneil@google.com>
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Reviewed-by: Damien Neil <dneil@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Fix comments, including duplicate is, wrong phrases and articles, misspellings, etc.
Change-Id: I8bfea53b9b275e649757cc4bee6a8a026ed9c7a4
Reviewed-on: https://go-review.googlesource.com/c/go/+/493035
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
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The initial purpose of PCALIGN was to identify code
where it would be beneficial to align code for performance,
but avoid cases where too many NOPs were added. On p10, it
is now necessary to enforce a certain alignment in some
cases, so the behavior of PCALIGN needs to be slightly
different. Code will now be aligned to the value specified
on the PCALIGN instruction regardless of number of NOPs added,
which is more intuitive and consistent with power assembler
alignment directives.
This also adds 64 as a possible alignment value.
The existing values used in PCALIGN were modified according to
the new behavior.
A testcase was updated and performance testing was done to
verify that this does not adversely affect performance.
Change-Id: Iad1cf5ff112e5bfc0514f0805be90e24095e932b
Reviewed-on: https://go-review.googlesource.com/c/go/+/485056
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Re-run all go:generate stringer commands. This mostly adds checks
that the constant values did not change, but does add new strings
for the debug/dwarf and internal/pkgbits packages.
Change-Id: I5fc41f20da47338152c183d45d5ae65074e2fccf
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Fixes#59331
Change-Id: I62156be2f2758c59349c3b02db6cf9140429c9e3
Reviewed-on: https://go-review.googlesource.com/c/go/+/481915
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Bypass: Ian Lance Taylor <iant@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Fixes the misuse of "a" vs "an", according to English grammatical
expectations and using https://www.a-or-an.com/
Change-Id: I53ac724070e3ff3d33c304483fe72c023c7cda47
Reviewed-on: https://go-review.googlesource.com/c/go/+/480536
Run-TryBot: shuang cui <imcusg@gmail.com>
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I noticed the one in path/filepath while reading the docs,
and the other ones were found via some quick grepping.
Change-Id: I386f2f74ef816a6d18aa2f58ee6b64dbd0147c9e
Reviewed-on: https://go-review.googlesource.com/c/go/+/478795
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Most of these are one-off mistakes. Only one file was all spaces.
Change-Id: I277c3ce4a4811aa4248c90676f66bc775ae8d062
Reviewed-on: https://go-review.googlesource.com/c/go/+/478976
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This change introduces the Compare and Compare32 functions
based on the total-ordering predicate in IEEE-754, section 5.10.
In particular,
* -NaN is ordered before any other value
* +NaN is ordered after any other value
* -0 is ordered before +0
* All other values are ordered the usual way
Compare-8 0.4537n ± 1%
Compare32-8 0.3752n ± 1%
geomean 0.4126n
Fixes#56491.
Change-Id: I5c9c77430a2872f380688c1b0a66f2105b77d5ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/467515
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Change-Id: I16ec916b47de2f417b681c8abff5a1375ddf491b
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It currently says only what it wasn't good for, which is not helpful.
Change-Id: I468c7f385c14eaca99788a94d53c30b729ed0944
Reviewed-on: https://go-review.googlesource.com/c/go/+/466276
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This change introduces the Compare and Compare32 functions
based on the total-ordering predicate in IEEE-754, section 5.10.
In particular,
* -NaN is ordered before any other value
* +NaN is ordered after any other value
* -0 is ordered before +0
* All other values are ordered the usual way
name time/op
Compare-8 0.24ns ± 1%
Compare32-8 0.24ns ± 0%
Fixes#56491.
Change-Id: I9444fbfefe26741794c4436a26d403b8da97bdaf
Reviewed-on: https://go-review.googlesource.com/c/go/+/459435
Run-TryBot: Ian Lance Taylor <iant@google.com>
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This operation converts a big.Int to float64,
reporting the accuracy of the result, with
a fast path in hardware.
Fixes#56984
Change-Id: I86d0fb0e105a06a4009986f2f5fd87a4d446f6f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/453115
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The existing implementation does a float64 to int64 conversion in order to check whether the number is odd, however it does not check for overflows. If an overflow occurs, the result is implementation-defined and while it happens to work on amd64 and i386, it produces an incorrect result on arm64 and possibly other architectures.
This change fixes that and also avoids calling isOddInt altogether if the base is +0, because it's unnecessary.
(I was considering avoiding the extra check if runtime.GOARCH is "amd64" or "i386", but I can't see this pattern being used anywhere outside the tests. And having separate files with build tags just for isOddInt() seems like an overkill)
Fixes#57465
Change-Id: Ieb243796194412aa6b98fac05fd19766ca2413ef
GitHub-Last-Rev: 3bfbd85c4c
GitHub-Pull-Request: golang/go#57494
Reviewed-on: https://go-review.googlesource.com/c/go/+/459815
Auto-Submit: Keith Randall <khr@golang.org>
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Allow GODEBUG users to report how many times a setting
resulted in non-default behavior.
Record non-default-behaviors for all existing GODEBUGs.
Also rework tests to ensure that runtime is in sync with runtime/metrics.All,
and generate docs mechanically from metrics.All.
For #56986.
Change-Id: Iefa1213e2a5c3f19ea16cd53298c487952ef05a4
Reviewed-on: https://go-review.googlesource.com/c/go/+/453618
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This will let us reuse it in crypto/ecdsa for the NIST scalar fields.
The main change in API is around encoding and decoding. The SetBytes +
ExpandFor sequence was hacky: SetBytes could produce a bigger size than
the modulus if leading zeroes in the top byte overflowed the limb
boundary, so ExpandFor had to check for and tolerate that. Also, the
caller was responsible for checking that the overflow was actually all
zeroes (which we weren't doing, exposing a crasher in decryption and
signature verification) and then for checking that the result was less
than the modulus. Instead, make SetBytes take a modulus and return an
error if the value overflows. Same with Bytes: we were always allocating
based on Size before FillBytes anyway, so now Bytes takes a modulus.
Finally, SetBig was almost only used for moduli, so replaced
NewModulusFromNat and SetBig with NewModulusFromBig.
Moved the constant-time bitLen to math/big.Int.BitLen. It's slower, but
BitLen is primarily used in cryptographic code, so it's safer this way.
Change-Id: Ibaf7f36d80695578cb80484167d82ce1aa83832f
Reviewed-on: https://go-review.googlesource.com/c/go/+/450055
Auto-Submit: Filippo Valsorda <filippo@golang.org>
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Reviewed-by: Roland Shoemaker <roland@golang.org>
Change-Id: I69065f8adf101fdb28682c55997f503013a50e29
Reviewed-on: https://go-review.googlesource.com/c/go/+/449757
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
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Programs that call Seed and then expect a specific sequence
of results from the global random source (using functions such as Int)
can be broken when a dependency changes how much it consumes
from the global random source. To avoid such breakages, programs
that need a specific result sequence should use NewRand(NewSource(seed))
to obtain a random generator that other packages cannot access.
Fixes#56319.
Change-Id: Idac33991b719d2c71f109f51dacb3467a649e01e
Reviewed-on: https://go-review.googlesource.com/c/go/+/451375
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We have been expanding our use of GODEBUG for compatibility,
and the current implementation forces a tradeoff between
freshness and efficiency. It parses the environment variable
in full each time it is called, which is expensive. But if clients
cache the result, they won't respond to run-time GODEBUG
changes, as happened with x509sha1 (#56436).
This CL changes the GODEBUG API to provide efficient,
up-to-date results. Instead of a single Get function,
New returns a *godebug.Setting that itself has a Get method.
Clients can save the result of New, which is no more expensive
than errors.New, in a global variable, and then call that
variable's Get method to get the value. Get costs only two
atomic loads in the case where the variable hasn't changed
since the last call.
Unfortunately, these changes do require importing sync
from godebug, which will mean that sync itself will never
be able to use a GODEBUG setting. That doesn't seem like
such a hardship. If it was really necessary, the runtime could
pass a setting to package sync itself at startup, with the
caveat that that setting, like the ones used by runtime itself,
would not respond to run-time GODEBUG changes.
Change-Id: I99a3acfa24fb2a692610af26a5d14bbc62c966ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/449504
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Change-Id: I7605bcbbaa64bb4273ad458a157b1c6011467973
Reviewed-on: https://go-review.googlesource.com/c/go/+/447915
Run-TryBot: Ian Lance Taylor <iant@google.com>
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Change-Id: Iabf955cdb161d02cb4a3e06f466b331e1b6eb2c2
Signed-off-by: cui fliter <imcusg@gmail.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/447456
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Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
This change improves the performance of Binomial by implementing an
algorithm that produces smaller intermediate values at each step.
Working with smaller big.Int values has the advantage that fewer allocations
and computations are required for each mathematical operation.
The algorithm used is the Multiplicative Formula, which is a well known
way of calculating the Binomial coefficient and is described at:
https://en.wikipedia.org/wiki/Binomial_coefficient#Multiplicative_formulahttps://en.wikipedia.org/wiki/Binomial_coefficient#In_programming_languages
In addition to that, an optimization has been made to remove a
redundant computation of (i+1) on each loop which has a measurable
impact when using big.Int.
Performance improvement measured on an M1 MacBook Pro
running the existing benchmark for Binomial:
name old time/op new time/op delta
Binomial-8 589ns ± 0% 435ns ± 0% -26.05% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
Binomial-8 1.02kB ± 0% 0.08kB ± 0% -92.19% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
Binomial-8 38.0 ± 0% 5.0 ± 0% -86.84% (p=0.000 n=10+10)
Change-Id: I5a830386dd42f062e17af88411dd74fcb110ded9
GitHub-Last-Rev: 6b2fca07de
GitHub-Pull-Request: golang/go#56339
Reviewed-on: https://go-review.googlesource.com/c/go/+/444315
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
For #20661.
Change-Id: I1e638cb619e643eadc210d71f92bd1af7bafc912
Reviewed-on: https://go-review.googlesource.com/c/go/+/436955
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: hopehook <hopehook@golangcn.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Dmitri Shuralyov
cui fliter
Oleksandr Redko
chanxuehong
qiulaidongfeng
Srinivas Pokala
root
Keith Randall
Michael Munday
Ian Lance Taylor
Alexander Yastrebov
Alan Donovan
Egon Elbre
Lynn Boger
Daniel Martí
Michael Pratt
Akhil Indurti
Than McIntosh
Valentin Deleplace
Rob Pike
Filippo Valsorda
Dmitry Panov
Russ Cox
ruinan
Eric Lagergren
Riccardo Gerosa
hopehook