The one-pass transformation is structured as a search over the input
machine for conditions that violate the one-pass requisites. At each
iteration, we should fully explore all non-input paths that proceed from
the current instruction; this is implemented via recursive check calls.
But when we reach instructions that demand input (InstRune*), these
should be put onto the search queue.
Instead of searching this way, the routine previously (effectively)
proceeded through the machine one instruction at a time until finding an
Inst{Match,Fail,Rune*}, calling check on each instruction. This caused
bug #11905, where the transformation stopped before rewriting all
InstAlts as InstAltMatches.
Further, the check function unnecessarily recurred on InstRune*
instructions. (I believe this helps to mask the above bug.)
This change also deletes some unused functions and duplicate test cases.
Fixes#11905.
Change-Id: I5b0b26efea3d3bd01c7479a518b5ed1b886701cd
Reviewed-on: https://go-review.googlesource.com/17195
Reviewed-by: Russ Cox <rsc@golang.org>
The prefix computation for onepass was incorrectly returning
complete=true when it encountered a beginning-of-text empty width match
(^) in the middle of an expression.
Fix by returning complete only when the prefix is followed by $ and then
an accepting state.
Fixes#11175.
Change-Id: Ie9c4cf5f76c1d2c904a6fb2f016cedb265c19fde
Reviewed-on: https://go-review.googlesource.com/16200
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
This helps users who wish to use separate Regexps in each goroutine to
avoid lock contention. Previously they had to parse the expression
multiple times to achieve this.
I used variants of the included benchmark to evaluate this change. I
used the arguments -benchtime 20s -cpu 1,2,4,8,16 on a machine with 16
hardware cores.
Comparing a single shared Regexp vs. copied Regexps, we can see that
lock contention causes huge slowdowns at higher levels of parallelism.
The copied version shows the expected linear speedup.
name old time/op new time/op delta
MatchParallel 366ns ± 0% 370ns ± 0% +1.09% (p=0.000 n=10+8)
MatchParallel-2 324ns ±28% 184ns ± 1% -43.37% (p=0.000 n=10+10)
MatchParallel-4 352ns ± 5% 93ns ± 1% -73.70% (p=0.000 n=9+10)
MatchParallel-8 480ns ± 3% 46ns ± 0% -90.33% (p=0.000 n=9+8)
MatchParallel-16 510ns ± 8% 24ns ± 6% -95.36% (p=0.000 n=10+8)
I also compared a modified version of Regexp that has no mutex and a
single machine (the "RegexpForSingleGoroutine" rsc mentioned in
https://github.com/golang/go/issues/8232#issuecomment-66096128).
In this next test, I compared using N copied Regexps vs. N separate
RegexpForSingleGoroutines. This shows that, even for this relatively
simple regex, avoiding the lock entirely would only buy about 10-12%
further improvement.
name old time/op new time/op delta
MatchParallel 370ns ± 0% 322ns ± 0% -12.97% (p=0.000 n=8+8)
MatchParallel-2 184ns ± 1% 162ns ± 1% -11.60% (p=0.000 n=10+10)
MatchParallel-4 92.7ns ± 1% 81.1ns ± 2% -12.43% (p=0.000 n=10+10)
MatchParallel-8 46.4ns ± 0% 41.8ns ±10% -9.78% (p=0.000 n=8+10)
MatchParallel-16 23.7ns ± 6% 20.6ns ± 1% -13.14% (p=0.000 n=8+8)
Updates #8232.
Change-Id: I15201a080c363d1b44104eafed46d8df5e311902
Reviewed-on: https://go-review.googlesource.com/16110
Reviewed-by: Russ Cox <rsc@golang.org>
From the XML spec: "XML processors should match character encoding
names in a case-insensitive way"
Fixes#12417.
Change-Id: I678c50152a49c14364be62b3f21ab9b9b009b24b
Reviewed-on: https://go-review.googlesource.com/14084
Reviewed-by: Russ Cox <rsc@golang.org>
json.Number is a special case which didn't have any checks and could result in invalid JSON.
Fixes#10281
Change-Id: Ie3e726e4d6bf6a6aba535d36f6107013ceac913a
Reviewed-on: https://go-review.googlesource.com/12250
Reviewed-by: Russ Cox <rsc@golang.org>
CRC-32 computation is stateless and the p slice does not get stored
anywhere. Thus, we mark the assembly functions as noescape so that
it doesn't believe that p leaks in:
func Update(crc uint32, tab *Table, p []byte) uint32
Before:
./crc32.go:153: leaking param: p
After:
./crc32.go:153: Update p does not escape
Change-Id: I52ba35b6cc544fff724327140e0c27898431d1dc
Reviewed-on: https://go-review.googlesource.com/17069
Reviewed-by: Russ Cox <rsc@golang.org>
This compares the behavior of server handlers and the net/http
Transport in both HTTP/1 and HTTP/2 mode and verifies they're the
same.
This also moves some client<->server tests into clientserver_test.go.
Many of them were in serve_test.go or transport_test.go but were
basically testing both.
h2_bundle.go is an update of the golang.org/x/net/http2 code
from https://golang.org/cl/17204 (x/net git rev c745c36eab10)
Fixes#13315Fixes#13316Fixes#13317
Fixes other stuff found in the process too
Updates #6891 (http2 support in general)
Change-Id: Id9c45fad44cdf70ac95d2b89e578d66e882d3cc2
Reviewed-on: https://go-review.googlesource.com/17205
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
We need a runtime check because the original issue is encountered
when running cross compiled windows program from linux. It's better
to give a meaningful crash message earlier than to segfault later.
The added test should not impose any measurable overhead to Go
programs.
For #12415.
Change-Id: Ib4a24ef560c09c0585b351d62eefd157b6b7f04c
Reviewed-on: https://go-review.googlesource.com/14207
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a comment/documentation change only but for a minor
code change in the file and package_ methods (move recognition
of semi to match grammar better).
Per request from r.
Change-Id: I81ec985cc5831074d9eb5e8ffbf7e59466284819
Reviewed-on: https://go-review.googlesource.com/17202
Reviewed-by: Rob Pike <r@golang.org>
The prefix includes a semicolon.
Change-Id: I4bdb79aa9931e835e297f3ea2c46a001cd123d56
Reviewed-on: https://go-review.googlesource.com/17200
Reviewed-by: Andrew Gerrand <adg@golang.org>
This change strips non-free license from Mark.Twain-Tom.Sawyer.txt along with all reference to Project Gutenberg in the file and the whole source tree. Making the file public domain again.
Fixes#13216
Change-Id: I2f41b0de225f627dde152efe93c006a4c24be668
Reviewed-on: https://go-review.googlesource.com/17196
Reviewed-by: Andrew Gerrand <adg@golang.org>
Write barriers in gcFlushBgCredit lead to very subtle bugs because it
executes after the getfull barrier. I tracked some bugs of this form
down before go:nowritebarrierrec was implemented. Ensure that they
don't reappear by making gcFlushBgCredit go:nowritebarrierrec.
Change-Id: Ia5ca2dc59e6268bce8d8b4c87055bd0f6e19bed2
Reviewed-on: https://go-review.googlesource.com/17052
Reviewed-by: Russ Cox <rsc@golang.org>
sighandler may run during STW, so write barriers are not allowed.
Change-Id: Icdf46be10ea296fd87e73ab56ebb718c5d3c97ac
Reviewed-on: https://go-review.googlesource.com/17007
Reviewed-by: Russ Cox <rsc@golang.org>
On multiprocessor machines, a file descriptor could be
closed twice in forkAndExecInChild. Consequently, the close
syscall returns the "fd out of range or not open" error
and forkAndExecInChild fails.
This changes forkAndExecInChild to ignore the error
returned by close(fd), as on other operating systems.
Fixes#12851.
Change-Id: I96a8463ce6599bfd1362353283e0329a00f738da
Reviewed-on: https://go-review.googlesource.com/17188
Reviewed-by: Rob Pike <r@golang.org>
Replace the cross platform but unsafe [4]uintptr type with a OS
specific type, sigset. Most OSes already define sigset, and this
change defines a suitable sigset for the OSes that don't (darwin,
openbsd). The OSes that don't use m.sigmask (windows, plan9, nacl)
now defines sigset as the empty type, struct{}.
The gain is strongly typed access to m.sigmask, saving a dynamic
size sanity check and unsafe.Pointer casting. Also, some storage is
saved for each M, since [4]uinptr was conservative for most OSes.
The cost is that OSes that don't need m.sigmask has to define sigset.
completes ./all.bash with GOOS linux, on amd64
completes ./make.bash with GOOSes openbsd, android, plan9, windows,
darwin, solaris, netbsd, freebsd, dragonfly, all amd64.
With GOOS=nacl ./make.bash failed with a seemingly unrelated error.
[Replay of CL 16942 by Elias Naur.]
Change-Id: I98f144d626033ae5318576115ed635415ac71b2c
Reviewed-on: https://go-review.googlesource.com/17033
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
This is a bit ugly but it's a useful test. Run go install -buildmode=shared std
and then go run run.go -linkshared (it passes on linux/amd64).
Change-Id: I5684c79cd03817fa1fc399788b7320f8535c08da
Reviewed-on: https://go-review.googlesource.com/16343
Reviewed-by: Russ Cox <rsc@golang.org>
Before, we reset the timer at the end of T.Parallel, which is okay
assuming that T.Parallel is the first thing in the test.
Snapshot the elapsed time at the beginning of Parallel and include it in
the total duration so that any time spent in the test before calling
Parallel is reported in the test duration as well.
Updates #12243.
Change-Id: Ieca553e1f801e16b9b6416463fa8f7fa65425185
Reviewed-on: https://go-review.googlesource.com/16989
Reviewed-by: Russ Cox <rsc@golang.org>
These tests were failing on one of the versions of cl/9345
("runtime: simplify buffered channels").
Change-Id: I920ffcd28de428bcb7c2d5a300068644260e1017
Reviewed-on: https://go-review.googlesource.com/16416
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Fixes#11959Fixes#12035
Skip the CallbackGC test on linux/arm. This test takes between 30 and 60
seconds to run by itself, and is run 4 times over the course of ./run.bash
(once during the runtime test, three times more later in the build).
Change-Id: I4e7d3046031cd8c08f39634bdd91da6e00054caf
Reviewed-on: https://go-review.googlesource.com/14485
Reviewed-by: Russ Cox <rsc@golang.org>
Original code is mistakenly panics on VirtualAlloc failure - we want
it to go looking for smaller memory region that VirtualAlloc will
succeed to allocate. Also return immediately if VirtualAlloc succeeds.
See rsc comment on issue #12587 for details.
I still don't have a test for this. So I can only hope that this
Fixes#12587
Change-Id: I052068ec627fdcb466c94ae997ad112016f734b7
Reviewed-on: https://go-review.googlesource.com/17169
Reviewed-by: Russ Cox <rsc@golang.org>
Get rid of residue after removing old parser.
Change-Id: I0dace1037d50959071a082c276f9f374eef6edb2
Reviewed-on: https://go-review.googlesource.com/17179
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
These are methods that are "obviously" going to get inlined -- until you build
with -l, when they can trigger a stack split at a bad time.
Fixes#11482
Change-Id: Ia065c385978a2e7fe9f587811991d088c4d68325
Reviewed-on: https://go-review.googlesource.com/17165
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Commit bbd1a1c prevented SIGPROF from scanning stacks that were being
copied, but it didn't prevent a stack copy (specifically a stack
shrink) from happening while SIGPROF is scanning the stack. As a
result, a stack copy may adjust stack barriers while SIGPROF is in the
middle of scanning a stack, causing SIGPROF to panic when it detects
an inconsistent stack barrier.
Fix this by taking the stack barrier lock while adjusting the stack.
In addition to preventing SIGPROF from scanning this stack, this will
block until any in-progress SIGPROF is done scanning the stack.
For 1.5.2.
Fixes#13362.
Updates #12932.
Change-Id: I422219c363054410dfa56381f7b917e04690e5dd
Reviewed-on: https://go-review.googlesource.com/17191
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Calling timeBeginPeriod changes Windows global timer resolution
from 15ms to 1ms. This used to improve Go runtime scheduler
performance, but not anymore. Thanks to @aclements, scheduler now
behaves the same way if we call timeBeginPeriod or not.
Remove call to timeBeginPeriod, since it is machine global
resource, and there are downsides of using low timer resolution.
See issue #8687 for details.
Fixes#8687
Change-Id: Ib7e41aa4a81861b62a900e0e62776c9ef19bfb73
Reviewed-on: https://go-review.googlesource.com/17164
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Yasuhiro MATSUMOTO <mattn.jp@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
- moved yySymType and token constants (L...) to lex.go
- removed oldparser flag and related code
- removed go generate that generated y.go
Fixes#13240.
Change-Id: I2576ec61ee1efe482f2a5132175725c9c02ef977
Reviewed-on: https://go-review.googlesource.com/17176
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This relocation is found in libgcc.a in the .eh_frame, and therefore
needs to be handled when doing an internal link.
Fixes#13375.
Change-Id: Idd9e8178e08851a101b43261a30939bcfaf394f9
Reviewed-on: https://go-review.googlesource.com/17173
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
It is not important to add, since it's only used for creating an error message,
but for consistency in the API between text/template and html/template
it should be provided here.
The implementation just calls the one in text/template.
Fixes#13349.
Change-Id: I0882849e06a58f1e38b00eb89d79ac39777309b2
Reviewed-on: https://go-review.googlesource.com/17172
Reviewed-by: Andrew Gerrand <adg@golang.org>
Introduce a try_ntype function which doesn't return an error upon
not finding a type. Use it instead of having separate repeated
token checks. Simpler, less code, and more efficient.
Change-Id: I81e482158b71901eb179470269349688636aa0ba
Reviewed-on: https://go-review.googlesource.com/17157
Reviewed-by: Chris Manghane <cmang@golang.org>
Sscanf doc says:
Newlines in the input must match newlines in the format.
However Sscanf didn't check newline in the end of input (EOF).
A test for the case is broken.
* check newline in EOF
* fix the test
* slightly simplify ss.doScanf
Fixes#12788
Change-Id: Iaf6b7d81324a72e557543ac22ecea5cecb72e0d6
Reviewed-on: https://go-review.googlesource.com/16165
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
This improves the documentation comment on gcMarkDone, replaces a
recursive call with a simple goto, and disables preemption before
stopping the world in accordance with the documentation comment on
stopTheWorldWithSema.
Updates #13363, but, sadly, doesn't fix it.
Change-Id: I6cb2a5836b35685bf82f7b1ce7e48a7625906656
Reviewed-on: https://go-review.googlesource.com/17149
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This improves stack barrier debugging messages in various ways:
1) Rather than printing only the remaining stack barriers (of which
there may be none, which isn't very useful), print all of the G's
stack barriers with a marker at the position the stack itself has
unwound to and a marker at the problematic stack barrier (where
applicable).
2) Rather than crashing if we encounter a stack barrier when there are
no more stkbar entries, print the same debug message we would if we
had encountered a stack barrier at an unexpected location.
Hopefully this will help with debugging #12528.
Change-Id: I2e6fe6a778e0d36dd8ef30afd4c33d5d94731262
Reviewed-on: https://go-review.googlesource.com/17147
Reviewed-by: Rick Hudson <rlh@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
The stack barrier locking functions use a simple cas lock because they
need to support trylock, but currently don't increment g.m.locks. This
is okay right now because they always run on the system stack or the
signal stack and are hence non-preemtible, but this could lead to
difficult-to-reproduce deadlocks if these conditions change in the
future.
Make these functions more robust by incrementing g.m.locks and making
them nosplit to enforce non-preemtibility.
Change-Id: I73d60a35bd2ad2d81c73aeb20dbd37665730eb1b
Reviewed-on: https://go-review.googlesource.com/17058
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ingo Oeser <nightlyone@googlemail.com>
Reviewed-by: Russ Cox <rsc@golang.org>
It started failing on the dragonfly builder at an unrelated commit
(one that changed the wording in a few comments in the compiler).
Created #13364 to track this.
Change-Id: I462880bed8ff565a9950e7e185de97d43999c5e2
Reviewed-on: https://go-review.googlesource.com/17143
Reviewed-by: Russ Cox <rsc@golang.org>
This appears to be an unintended omission. The check func is declared
just above, and the err value from template.Parse is captured rather
than discarded via blank identifier. All following calls that similarly
return err are checked, so it can't be that this example elides error
checking for brevity. Finally, if you look at Example_autoescaping,
it does check err from template.Parse and its code is very similar.
Change-Id: I076e1846302d5f2cdb1d027ed85ca0db85e33ace
Reviewed-on: https://go-review.googlesource.com/17170
Reviewed-by: Andrew Gerrand <adg@golang.org>
Found by cmd/vet
Change-Id: I29dd207ecd40fe703054e8ad4e81b3267ca89da2
Reviewed-on: https://go-review.googlesource.com/17160
Reviewed-by: David Crawshaw <crawshaw@golang.org>
