This works around what appears to be a bug in current clang (2018-11-09).
Details are in the comment in the code.
Change-Id: Ib4783b6c03d531c69ebc4cb0ac023bea5bee7d40
Reviewed-on: https://go-review.googlesource.com/c/148819
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
cgocall could previously invoke the race detector on an M whose P had
been retaken. The race detector would attempt to use the P-local state
from this stale P, racing with the thread that was actually wired to
that P. The result was memory corruption of ThreadSanitizer's internal
data structures that presented as hard-to-understand assertion failures
and segfaults.
Reorder cgocall so that it always acquires a P before invoking the race
detector, and add a test that stresses the interaction between cgo and
the race detector to protect against future bugs of this kind.
Fixes#27660.
Change-Id: Ide93f96a23490314d6647547140e0a412a97f0d4
Reviewed-on: https://go-review.googlesource.com/c/148717
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
This change fixes a bug wherein freeing a scavenged span that didn't
coalesce with any neighboring spans would result in that span getting
scavenged again. This case may actually be a common occurance because
"freeing" span trimmings and newly-grown spans end up using the same
codepath. On systems where madvise is relatively expensive, this can
have a large performance impact.
This change also cleans up some of this logic in freeSpanLocked since
a number of factors made the coalescing code somewhat difficult to
reason about with respect to scavenging. Notably, the way the
needsScavenge boolean is handled could be better expressed and the
inverted conditions (e.g. !after.released) can make things even more
confusing.
Fixes#28595.
Change-Id: I75228dba70b6596b90853020b7c24fbe7ab937cf
Reviewed-on: https://go-review.googlesource.com/c/147559
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
During walkexpr, we were assessing whether shifts were bounded.
However, that information was dropped on the floor during SSA conversion.
The SSA backend already finds all bounded shifts that walkexpr could have,
and at negligible extra cost (0.02% in alloc, CPU undetectable).
Change-Id: Ieda1af1a2a3ec99bfdc2b0b704c9b80ce8a34486
Reviewed-on: https://go-review.googlesource.com/c/148897
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This change makes use of the cc versions of the AND, OR, XOR
instructions, omitting the need for a CMP instruction.
In many test programs and in the go binary, this reduces the
size of 20-30 functions by at least 1 instruction, many in
runtime.
Testcase added to test/codegen/comparisons.go
Change-Id: I6cc1ca8b80b065d7390749c625bc9784b0039adb
Reviewed-on: https://go-review.googlesource.com/c/143059
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When main.main returns, the process exits, so there's no need to cancel contexts.
This change was initially reviewed as
https://go-review.googlesource.com/c/go/+/106915/4
but somehow I messed up and committed patchset 5, which was
effectively empty.
Change-Id: Ic4250eb6563af9bc734e429aafc7081ca7d0e012
Reviewed-on: https://go-review.googlesource.com/c/148758
Reviewed-by: Alan Donovan <adonovan@google.com>
This change introduces two optimizations together,
one for recursive and one for non-recursive stacks.
For recursive stacks, we introduce the new entry
at the beginning of the cache, so it can be found first.
This adds an extra read and write.
While we're here, switch from fastrandn, which does a multiply,
to fastrand % n, which does a shift.
For non-recursive stacks, split the cache from [16]pcvalueCacheEnt
into [2][8]pcvalueCacheEnt, and add a very cheap associative lookup.
name old time/op new time/op delta
StackCopyPtr-8 118ms ± 1% 106ms ± 2% -9.56% (p=0.000 n=17+18)
StackCopy-8 95.8ms ± 1% 87.0ms ± 3% -9.11% (p=0.000 n=19+20)
StackCopyNoCache-8 135ms ± 2% 139ms ± 1% +3.06% (p=0.000 n=19+18)
During make.bash, the association function used has this return distribution:
percent count return value
53.23% 678797 1
46.74% 596094 0
It is definitely not perfect, but it is pretty good,
and that's all we need.
Change-Id: I2cabb1d26b99c5111bc28f427016a2a5e6c620fd
Reviewed-on: https://go-review.googlesource.com/c/110564
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Pointers to compound objects (structs, slices, arrays, maps) are only
followed by fmt if the pointer is at the top level of an argument. This
is to minimise the chances of fmt running into loops.
However, vet did not follow this rule. It likely doesn't help that fmt
does not document that restriction well, which is being tracked in
#28625.
Updates #27672.
Change-Id: Ie9bbd9b974eda5ab9a285986d207ef92fca4453e
Reviewed-on: https://go-review.googlesource.com/c/147997
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
fmt's godoc reads:
For compound objects, the elements are printed using these
rules, recursively, laid out like this:
struct: {field0 field1 ...}
array, slice: [elem0 elem1 ...]
maps: map[key1:value1 key2:value2 ...]
pointer to above: &{}, &[], &map[]
That is, a pointer to a struct, array, slice, or map, can be correctly
printed by fmt if the type pointed to can be printed without issues.
vet was only following this rule for pointers to structs, omitting
arrays, slices, and maps. Fix that, and add tests for all the
combinations.
Updates #27672.
Change-Id: Ie61ebe1fffc594184f7b24d7dbf72d7d5de78309
Reviewed-on: https://go-review.googlesource.com/c/147758
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
This optimization is not sound if A, B, or C
might overlap with each other.
Thanks to Michael Munday for pointing this
out during the review of CL 143479.
This reduces the number of times this optimization
triggers during make.bash from 386 to 74.
This is unfortunate, but I don't see an obvious way around it,
short of souping up the disjointness analysis.
name old object-bytes new object-bytes delta
Template 507kB ± 0% 507kB ± 0% +0.13% (p=0.008 n=5+5)
Unicode 225kB ± 0% 225kB ± 0% ~ (all equal)
GoTypes 1.85MB ± 0% 1.85MB ± 0% +0.02% (p=0.008 n=5+5)
Flate 328kB ± 0% 328kB ± 0% ~ (all equal)
GoParser 402kB ± 0% 402kB ± 0% ~ (all equal)
Reflect 1.41MB ± 0% 1.41MB ± 0% ~ (all equal)
Tar 457kB ± 0% 458kB ± 0% +0.20% (p=0.008 n=5+5)
XML 600kB ± 0% 601kB ± 0% +0.03% (p=0.008 n=5+5)
Change-Id: Ida408cb627145ba9faf473a78606f050c2f3f51c
Reviewed-on: https://go-review.googlesource.com/c/145208
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
This CL add support for converting a returned cursor (presented
to this package as a driver.Rows) and scanning it into a *Rows.
Fixes#28515
Change-Id: Id8191c568dc135af9e5e8555efcd01987708edcb
Reviewed-on: https://go-review.googlesource.com/c/145738
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Cleans things up quite a bit.
There's still a few more, like runtime.cmpstring, which might also
be worth fixing.
Change-Id: Ide18dd621efc129cc686db223f47fa0b044b5580
Reviewed-on: https://go-review.googlesource.com/c/148578
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The environment variable is no longer necessary as we now plan to
transition to the new vet by replacing it in a single step,
and we really don't want to add more environment variables.
Fixes#28636
Change-Id: Ib85e5c0d61213b7b9f6a53d9376fec29525df971
Reviewed-on: https://go-review.googlesource.com/c/148497
Run-TryBot: Alan Donovan <adonovan@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This is a simple tweak to allow a bit more mid-stack inlining.
In cases like this:
func f() {
g()
}
We'd really like to inline f into its callers. It can't hurt.
We implement this optimization by making calls a bit cheaper, enough
to afford a single call in the function body, but not 2.
The remaining budget allows for some argument modification, or perhaps
a wrapping conditional:
func f(x int) {
g(x, 0)
}
func f(x int) {
if x > 0 {
g()
}
}
Update #19348
Change-Id: Ifb1ea0dd1db216c3fd5c453c31c3355561fe406f
Reviewed-on: https://go-review.googlesource.com/c/147361
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: David Chase <drchase@google.com>
Add unexported unlinkat, openat, and fstatat calls, so that
the internal/syscall/unix package can use them.
Change-Id: I1df81ecae6427211dd392ec68c9f020fe131a526
Reviewed-on: https://go-review.googlesource.com/c/148457
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Now, this is embarrassing. While preparing CL 142818, I noticed a
possible vulnerability in the existing code which I was rewriting. I
took a note to go back and assess if it was indeed an issue, and in case
start the security release process. The note unintentionally slipped
into the commit. Fortunately, there was no vulnerability.
What caught my eye was that I had fixed the calculation of the minimum
encrypted payload length from
roundUp(explicitIVLen+macSize+1, blockSize)
to (using the same variable names)
explicitIVLen + roundUp(macSize+1, blockSize)
The explicit nonce sits outside of the encrypted payload, so it should
not be part of the value rounded up to the CBC block size.
You can see that for some values of the above, the old result could be
lower than the correct value. An unexpectedly short payload might cause
a panic during decryption (a DoS vulnerability) or even more serious
issues due to the constant time code that follows it (see for example
Yet Another Padding Oracle in OpenSSL CBC Ciphersuites [1]).
In practice, explicitIVLen is either zero or equal to blockSize, so it
does not change the amount of rounding up necessary and the two
formulations happen to be identical. Nothing to see here.
It looked more suspicious than it is in part due to the fact that the
explicitIVLen definition moved farther into hc.explicitNonceLen() and
changed name from IV (which suggests a block length) to nonce (which
doesn't necessarily). But anyway it was never meant to surface or be
noted, except it slipped, so here we are for a boring explanation.
[1] https://blog.cloudflare.com/yet-another-padding-oracle-in-openssl-cbc-ciphersuites/
Change-Id: I365560dfe006513200fa877551ce7afec9115fdf
Reviewed-on: https://go-review.googlesource.com/c/147637
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Miscellaneous additional conversions from raw syscalls
to using their libc equivalent.
Update #17490
Change-Id: If9ab22cc1d676c1f20fb161ebf02b0c28f71585d
Reviewed-on: https://go-review.googlesource.com/c/148257
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Pass the Go language version specified in the go.mod file to
cmd/compile.
Also, change the behavior when the go.mod file requests a Go version
that is later than the current one. Previously cmd/go would give a
fatal error in this situation. With this change it attempts the
compilation, and if (and only if) the compilation fails it adds a note
saying that the requested Go version is newer than the known version.
This is as described in https://golang.org/issue/28221.
Updates #28221.
Change-Id: I46803813e7872d4a418a3fd5299880be3b73a971
Reviewed-on: https://go-review.googlesource.com/c/147278
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This will be used by later commits in this sequence.
Updates #28221
Change-Id: I2b22b9f88a0183636cde9509606f03f079eb33f1
Reviewed-on: https://go-review.googlesource.com/c/147277
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
There are still some references to the bare Syscall functions
in the stdlib. I will root those out in a following CL.
(This CL is big enough as it is.)
Most are in vendor directories:
cmd/vendor/golang.org/x/sys/unix/
vendor/golang_org/x/net/route/syscall.go
syscall/bpf_bsd.go
syscall/exec_unix.go
syscall/flock.go
Update #17490
Change-Id: I69ab707811530c26b652b291cadee92f5bf5c1a4
Reviewed-on: https://go-review.googlesource.com/c/141639
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
It is possible to create certain recursive type declarations involving
alias types which cause the type-checker to produce an (invalid) type
for the alias because it is not yet available. By type-checking alias
declarations in a 2nd phase, the problem is mitigated a bit since it
requires more convoluted alias declarations for the problem to appear.
Also re-enable testing of fixedbugs/issue27232.go again (which was the
original cause for this change).
Updates #28576.
Change-Id: If6f9656a95262e6575b01c4a003094d41551564b
Reviewed-on: https://go-review.googlesource.com/c/147597
Reviewed-by: Alan Donovan <adonovan@google.com>
Sync @ fde099a (Oct 26, 2018)
Also update misc/nacl/testzip.proto to include new testdata.
Change-Id: If41590be9f395a591056e89a417b589c4ba71b1a
Reviewed-on: https://go-review.googlesource.com/c/147979
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This mainly entails writing compiler output files to a temporary
directory, as well as the corrupted files in TestVersionHandling.
Updates #28387
Change-Id: I6b3619a91fff27011c7d73daa4febd14a6c5c348
Reviewed-on: https://go-review.googlesource.com/c/146119
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This change updates the expected output of the delve debugging session
in the TestNexting internal/ssa test, aligning it with the changes
introduced in CL 147360 and earlier.
Change-Id: I1cc788d02433624a36f4690f24201569d765e5d3
Reviewed-on: https://go-review.googlesource.com/c/147998
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This change updates the expected output of the gdb debugging session
in the TestNexting internal/ssa test, aligning it with the changes
introduced in CL 147360.
Fixes the longtest builder.
Change-Id: I5b5c22e1cf5e205967ff8359dc6c1485c815428e
Reviewed-on: https://go-review.googlesource.com/c/147957
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Like every other command's -h flag. To achieve this, pass the command's
usage function to the cmdflag package, since that package is used by
multiple commands and cannot directly access *base.Command.
This also lets us get rid of testFlag1 and testFlag2, and instead have
contiguous raw strings for the test and testflag help docs.
Fixes#26999.
Change-Id: I2ebd66835ee61fa83270816a01fa312425224bb3
Reviewed-on: https://go-review.googlesource.com/c/144558
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
This change fixes a TestFormat failure in fmt_test by adding a
recently introduced new known format (%q for syntax.Error).
Fixes#28621
Change-Id: I026ec88c334549a957a692c1652a860c57e23dae
Reviewed-on: https://go-review.googlesource.com/c/147837
Reviewed-by: Ian Lance Taylor <iant@golang.org>
In ARM64 ABI, R18 is the "platform register", the use of which is
OS specific. The OS could choose to reserve this register. In
practice, it seems fine to use R18 on Linux but not on darwin (iOS).
Rename R18 to R18_PLATFORM to prevent accidental use. There is no
R18 usage within the standard library (besides tests, which are
updated).
Fixes#26110
Change-Id: Icef7b9549e2049db1df307a0180a3c90a12d7a84
Reviewed-on: https://go-review.googlesource.com/c/147218
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Dead-code eliminating labels is tricky because there might
be gotos that can still reach them.
Bug probably introduced with CL 91056
Fixes#28616
Change-Id: I6680465134e3486dcb658896f5172606cc51b104
Reviewed-on: https://go-review.googlesource.com/c/147817
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Iskander Sharipov <iskander.sharipov@intel.com>
This change adds the vet-lite command (the future cmd/vet) and all its
dependencies from x/tools, but not its tests and their dependencies.
It was created with these commands:
$ (cd $GOPATH/src/golang.org/x/tools && git checkout c76e1ad)
$ cd GOROOT/src/cmd
$ govendor add $(go list -deps golang.org/x/tools/go/analysis/cmd/vet-lite | grep golang.org/x/tools)
$ rm -fr $(find vendor/golang.org/x/tools/ -name testdata)
$ rm $(find vendor/golang.org/x/tools/ -name \*_test.go)
I feel sure I am holding govendor wrong. Please advise.
A followup CL will make cmd/vet behave like vet-lite, initially just
for users that opt in, and soon after for all users, at which point
cmd/vet will be replaced in its entirety by a copy of vet-lite's small
main.go.
In the meantime, anyone can try the new tool using these commands:
$ go build cmd/vendor/golang.org/x/tools/go/analysis/cmd/vet-lite
$ export GOVETTOOL=$(which vet-lite)
$ go vet your/project/...
Change-Id: Iea168111a32ce62f82f9fb706385ca0f368bc869
Reviewed-on: https://go-review.googlesource.com/c/147444
Reviewed-by: Russ Cox <rsc@golang.org>
On AIX, cmd/link needs two information in order to generate a dynamic
import, the library and its object needed. Currently, cmd/link isn't
able to retrieve this object only with the name of the library.
Therefore, the library pattern in cgo_import_dynamic must be
"lib.a/obj.o".
Change-Id: Ib8b8aaa9807c9fa6af46ece4e312d58073ed6ec1
Reviewed-on: https://go-review.googlesource.com/c/146957
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Previously we panicked if the number of methods present for an embedded
field was >= 32. This change removes that limit and now StructOf
dynamically calls itself to create space for the number of methods.
Fixes#25402
Change-Id: I3b1deb119796d25f7e6eee1cdb126327b49a0b5e
GitHub-Last-Rev: 16da71ad6b
GitHub-Pull-Request: golang/go#26865
Reviewed-on: https://go-review.googlesource.com/c/128479
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
