overLoadFactor used a uintptr for its calculations.
When the number of potential buckets was large,
perhaps due to a coding error or corrupt/malicious user input
leading to a very large map size hint,
this led to overflow on 32 bit systems.
This overflow resulted in an infinite loop.
Prevent it by always using a 64 bit calculation.
Updates #20195
Change-Id: Iaabc710773cd5da6754f43b913478cc5562d89a2
Reviewed-on: https://go-review.googlesource.com/42185
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Noticed while adding to the bitset implementation
in cmd/compile/internal/gc.
The (Com (Const)) optimizations were already present
in the AMD64 lowered optimizations.
They trigger 118, 44, 262, and 108 times
respectively for int sizes 8, 16, 32, and 64
in a run of make.bash.
The (Or (And)) optimization is new.
It triggers 3 times for int size 8
and once for int size 64 during make.bash,
in packages internal/poll, reflect,
encoding/asn1, and go/types,
so there is a bit of natural test coverage.
Change-Id: I44072864ff88831d5ec7dce37c516d29df056e98
Reviewed-on: https://go-review.googlesource.com/41758
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Per gri's suggestion on CL 41623,
add a comment to trackAllTypes
about the trade-offs of enabling it.
Change-Id: Iec42b0da7933543200729003d1b2c6e0d9dcc5f0
Reviewed-on: https://go-review.googlesource.com/42186
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The generated test cases had their arguments reversed, putting them back
in order makes those tests pass.
CMPPS SRC, DEST, CC
Change-Id: Ie15021edc533d5681a6a78d10d88b665e3de9017
Reviewed-on: https://go-review.googlesource.com/42097
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
I want to move the SHIDDEN type bit into Attribute, but AttrHidden is already
there and means something completely different, so rename it. (I'll give the
SHIDDEN bit a better name when it moves too).
Change-Id: I075403d9542b7626d4c1f6db9094329c4181aad3
Reviewed-on: https://go-review.googlesource.com/42024
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
since there current version suffers from a copy'n'paste error.
Change-Id: I1ef97a4413198dde10c5c926a2a9806724cd6d44
Reviewed-on: https://go-review.googlesource.com/42095
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Without this, T can sneak through to the backend
with its width unknown.
Fixes#20174
Change-Id: I9b21e0e2641f75e360cc5e45dcb4eefe8255b675
Reviewed-on: https://go-review.googlesource.com/42175
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Updates #18089.
Test for that issue; it was inadvertently fixed
by CL 34988. Ensure that we don't regress on the fix.
Change-Id: Icb85fc20dbb0a47f028f088281319b552b16759d
Reviewed-on: https://go-review.googlesource.com/42173
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Fixes#7121.
CL 31173 inadvertently fixed this issue in the Go1.8 cycle.
This CL enables the test for that issue.
Change-Id: I8e73b41f646fa89c75bff833c1b07e1cdb2b1e62
Reviewed-on: https://go-review.googlesource.com/42149
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently Go sets the system-wide timer resolution to 1ms the whole
time it's running. This has negative affects on system performance and
power consumption. Unfortunately, simply reducing the timer resolution
to the default 15ms interferes with several sleeps in the runtime
itself, including sysmon's ability to interrupt goroutines.
This commit takes a hybrid approach: it only reduces the timer
resolution when the Go process is entirely idle. When the process is
idle, nothing needs a high resolution timer. When the process is
non-idle, it's already consuming CPU so it doesn't really matter if
the OS also takes timer interrupts more frequently.
Updates #8687.
Change-Id: I0652564b4a36d61a80e045040094a39c19da3b06
Reviewed-on: https://go-review.googlesource.com/38403
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
(ADDconst [c] x) && !isARMImmRot(uint32(c)) && isARMImmRot(uint32(-c)) -> (SUBconst [int64(int32(-c))] x)
(SUBconst [c] x) && !isARMImmRot(uint32(c)) && isARMImmRot(uint32(-c)) -> (ADDconst [int64(int32(-c))] x)
Currently
a = a + 0xfffffff1 is compiled to （variable a is in R0)
MVN $14, R11
ADD R11, R0, R0
After applying the above 2 rules, it becomes
SUB $15, R0, R0
(BICconst [c] (BICconst [d] x)) -> (BICconst [int64(int32(c|d))] x)
This rule also optimizes the generated ARM code.
The other rules are added to avoid to generate less optimized ARM code
when substitutions ADD->SUB happen.
Change-Id: I3ead9aae2b446b674e2ab42d37259d38ceb93a4d
Reviewed-on: https://go-review.googlesource.com/41679
Reviewed-by: Keith Randall <khr@golang.org>
Instead of playing whack-a-mole finding all
the non-dowidth'd expressions that can sneak
out of the frontend and then deciding on
just the right place to handle them,
use a big hammer.
Fixes#20152
Change-Id: Id452d9e8c4e9585216bd8bf0e0004c85aba4f9f7
Reviewed-on: https://go-review.googlesource.com/42021
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently the pprof tests re-symbolize PCs in profiles, and do so in a
way that can't handle inlining. Proto profiles already contain full
symbol information, so this modifies the tests to use the symbol
information already present in the profile.
Change-Id: I63cd491de7197080fd158b1e4f782630f1bbbb56
Reviewed-on: https://go-review.googlesource.com/41255
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
When running a Query on Stmt a dependency is added to the stmt and
rows. To do that it needs a reference to Rows, so the releaseConn
function is defined after the definition. However the
rows.initContextClose was set to run before the releaseConn was
set on rows, setting up a situation where the connection could
be canceled before the releaseConn was set and resulting in
a segfault.
Fixes#20160
Change-Id: I5592e7db2cf653dfc48d42cbc2b03ca20501b1a0
Reviewed-on: https://go-review.googlesource.com/42139
Run-TryBot: Daniel Theophanes <kardianos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Currently _TinySizeClass is untyped, which means it can accidentally
be used as a spanClass (not that I would know this from experience or
anything). Make it an int8 to avoid this mix up.
This is a cherry-pick of dev.garbage commit 81b74bf9c5.
Change-Id: I1e69eccee436ea5aa45e9a9828a013e369e03f1a
Reviewed-on: https://go-review.googlesource.com/41254
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
This is no longer necessary now that we can more efficiently consult
the span's noscan bit.
This is a cherry-pick of dev.garbage commit 312aa09996.
Change-Id: Id0b00b278533660973f45eb6efa5b00f373d58af
Reviewed-on: https://go-review.googlesource.com/41252
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Currently, we mix objects with pointers and objects without pointers
("noscan" objects) together in memory. As a result, for every object
we grey, we have to check that object's heap bits to find out if it's
noscan, which adds to the per-object cost of GC. This also hurts the
TLB footprint of the garbage collector because it decreases the
density of scannable objects at the page level.
This commit improves the situation by using separate spans for noscan
objects. This will allow a much simpler noscan check (in a follow up
CL), eliminate the need to clear the bitmap of noscan objects (in a
follow up CL), and improves TLB footprint by increasing the density of
scannable objects.
This is also a step toward eliminating dead bits, since the current
noscan check depends on checking the dead bit of the first word.
This has no effect on the heap size of the garbage benchmark.
We'll measure the performance change of this after the follow-up
optimizations.
This is a cherry-pick from dev.garbage commit d491e550c3. The only
non-trivial merge conflict was in updatememstats in mstats.go, where
we now have to separate the per-spanclass stats from the per-sizeclass
stats.
Change-Id: I13bdc4869538ece5649a8d2a41c6605371618e40
Reviewed-on: https://go-review.googlesource.com/41251
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
In particular, this says that Frames.Function uniquely identifies a
function within a program. We depend on this in various places that
use runtime.Frames in std, but it wasn't actually written down.
Change-Id: Ie7ede348c17673e11ae513a094862b60c506abc5
Reviewed-on: https://go-review.googlesource.com/41610
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reverts commit 3d86d45dd6.
Reason for revert: Fixing a different way. See #20008.
Change-Id: I6f4382ffdfff83a4504b013ba37100319b2c1aad
Reviewed-on: https://go-review.googlesource.com/42138
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The code in #20162 contains an embedded interface.
It didn't get dowidth'd by the frontend,
and during DWARF generation, ngotype asked
for a string description of it,
which triggered a request for the number of fields
in the interface, which triggered a dowidth,
which is disallowed in the backend.
The other changes in this CL are to support the test.
Fixes#20162
Change-Id: I4d0be5bd949c361d4cdc89a8ed28b10977e40cf9
Reviewed-on: https://go-review.googlesource.com/42131
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Now that it only takes small values.
Change-Id: I08086d392529d8775b470d65afc2475f8d0e7f4a
Reviewed-on: https://go-review.googlesource.com/42030
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
It used to be simple, and then it got complicated for speed (to reduce
allocations, mostly), but that involved a mutex and hurt multi-core
performance, contending on the mutex.
A change was sent to try to improve that mutex contention in
https://go-review.googlesource.com/c/42110/2/src/net/http/server.go
but that introduced its own allocations (the string->interface{}
boxing for the sync.Map key), which runs counter to the whole point of
that statusLine function: to remove allocations.
Instead, make the code simple again and not have a mutex. It's a bit
slower for the single-core case, but nobody with a single-user HTTP
server cares about 50 nanoseconds:
name old time/op new time/op delta
ResponseStatusLine 37.5ns ± 2% 87.1ns ± 2% +132.42% (p=0.029 n=4+4)
ResponseStatusLine-2 63.1ns ± 1% 43.1ns ±12% -31.67% (p=0.029 n=4+4)
ResponseStatusLine-4 53.8ns ± 8% 40.2ns ± 2% -25.29% (p=0.029 n=4+4)
name old alloc/op new alloc/op delta
ResponseStatusLine 0.00B ±NaN% 0.00B ±NaN% ~ (all samples are equal)
ResponseStatusLine-2 0.00B ±NaN% 0.00B ±NaN% ~ (all samples are equal)
ResponseStatusLine-4 0.00B ±NaN% 0.00B ±NaN% ~ (all samples are equal)
name old allocs/op new allocs/op delta
ResponseStatusLine 0.00 ±NaN% 0.00 ±NaN% ~ (all samples are equal)
ResponseStatusLine-2 0.00 ±NaN% 0.00 ±NaN% ~ (all samples are equal)
ResponseStatusLine-4 0.00 ±NaN% 0.00 ±NaN% ~ (all samples are equal)
(Note the code could be even simpler with fmt.Fprintf, but that is
relatively slow and involves a bunch of allocations getting arguments
into interface{} for the call)
Change-Id: I1fa119132dbbf97a8e7204ce3e0707d433060da2
Reviewed-on: https://go-review.googlesource.com/42133
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Using 'go build -tags "foo,bar"' might seem to work when you wanted
-tags "foo bar", since they make up a single tag that doesn't exist and
the build is unaffected.
Instead, error on any tag that contains a comma.
Fixes#18800.
Change-Id: I6641e03e2ae121c8878d6301c4311aef97026b73
Reviewed-on: https://go-review.googlesource.com/41951
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The comment for Cmd.Stdout and Cmd.Stderr says that it's safe to
set both to the same writer, but it doesn't say that this only
works when both writers are comparable.
This change updates the comment to explain that using a
non-comparable writer may still lead to a race.
Fixes#19804
Change-Id: I63b420034666209a2b6fab48b9047c9d07b825e2
Reviewed-on: https://go-review.googlesource.com/42052
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Profile labels added by the user using pprof.Do, if present will
be in a *labelMap stored in the unsafe.Pointer 'tag' field of
the profile map entry. This change extracts the labels from the tag
field and writes them to the profile proto.
Change-Id: Ic40fdc58b66e993ca91d5d5effe0e04ffbb5bc46
Reviewed-on: https://go-review.googlesource.com/39613
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
If g1 sets its labels and then they are copied into a profile buffer
and then g2 reads the profile buffer and inspects the labels,
the race detector must understand that g1's recording of the labels
happens before g2's use of the labels. Make that so.
Fixes race test failure in CL 39613.
Change-Id: Id7cda1c2aac6f8eef49213b5ca414f7154b4acfa
Reviewed-on: https://go-review.googlesource.com/42111
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
More specifically, allow Unicode letters in the directories of GitHub
repositories, which can occur and don't have a valid reason to be
disallowed by go get.
Do so by using a predefined character class, the Unicode character
property class \p{L} that describes the Unicode characters that are
letters:
http://www.regular-expressions.info/unicode.html#category
Since it's not possible to create GitHub usernames or repositories
containing Unicode letters at this time, those parts of the import path
are still restricted to ASCII letters only.
Fix name of tested func in t.Errorf messages.
Fixes#18660.
Change-Id: Ia0ef4742bfd8317d989ef1eb1d7065e382852fe2
Reviewed-on: https://go-review.googlesource.com/41822
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
