As part of #42026, these helpers from io/ioutil were moved to os.
(ioutil.TempFile and TempDir became os.CreateTemp and MkdirTemp.)
Update the Go tree to use the preferred names.
As usual, code compiled with the Go 1.4 bootstrap toolchain
and code vendored from other sources is excluded.
ReadDir changes are in a separate CL, because they are not a
simple search and replace.
For #42026.
Change-Id: If318df0216d57e95ea0c4093b89f65e5b0ababb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/266365
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
These will be used in a following CL to perform larger bit clear and bit
set than And8/Or8.
Change-Id: I60f7b1099e29b69eb64add77564faee862880a8d
Reviewed-on: https://go-review.googlesource.com/c/go/+/260977
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Trust: Michael Pratt <mpratt@google.com>
On 386 and arm, unaligned 64-bit atomics aren't safe, so we check for
this and panic. Currently, we panic by dereferencing nil, which may be
expedient but is pretty user-hostile since it gives no hint of what
the actual problem was.
This CL replaces this with an actual panic. The only subtlety here is
now the atomic assembly implementations are calling back into Go, so
they have to play nicely with stack maps and stack scanning. On 386,
this just requires declaring NO_LOCAL_POINTERS. On arm, this is
somewhat more complicated: first, we have to move the alignment check
into the functions that have Go signatures. Then we have to support
both the tail call from these functions to the underlying
implementation (which requires that they have no frame) and the call
into Go to panic (which requires that they have a frame). We resolve
this by forcing them to have no frame and setting up the frame
manually just before the panic call.
Change-Id: I19f1e860045df64088013db37a18acea47342c69
Reviewed-on: https://go-review.googlesource.com/c/go/+/262778
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
This drops package prefixes from the assembly code on 386 and arm. In
addition to just being nicer, this allows the assembler to
automatically pick up the argument stack map from the Go signatures of
these functions. This doesn't matter right now because these functions
never call back out to Go, but prepares us for the next CL.
Change-Id: I90fed7d4dd63ad49274529c62804211b6390e2e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/262777
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Introduce GOOS=ios for iOS systems. GOOS=ios matches "darwin"
build tag, like GOOS=android matches "linux" and GOOS=illumos
matches "solaris". Only ios/arm64 is supported (ios/amd64 is
not).
GOOS=ios and GOOS=darwin remain essentially the same at this
point. They will diverge at later time, to differentiate macOS
and iOS.
Uses of GOOS=="darwin" are changed to (GOOS=="darwin" || GOOS=="ios"),
except if it clearly means macOS (e.g. GOOS=="darwin" && GOARCH=="amd64"),
it remains GOOS=="darwin".
Updates #38485.
Change-Id: I4faacdc1008f42434599efb3c3ad90763a83b67c
Reviewed-on: https://go-review.googlesource.com/c/go/+/254740
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
CL 249962 added wasm StorepNoWB implementation in assembly, it's now
like all other architectures. This CL adds a general test that the
second param of StorepNoWB must be force to escape.
Fixes#40975
Change-Id: I1eccc7e50a3ec742a1912d65f25b15f9f5ad9241
Reviewed-on: https://go-review.googlesource.com/c/go/+/249761
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The second argument of StorepNoWB must be forced to escape.
The current Go code does not explicitly enforce that property.
By implementing in assembly, and not using go:noescape, we
force the issue.
Test is in CL 249761. Issue #40975.
This CL is needed for CL 249917, which changes how go:notinheap
works and breaks the previous StorepNoWB wasm code.
I checked for other possible errors like this. This is the only
go:notinheap that isn't in the runtime itself.
Change-Id: I43400a806662655727c4a3baa8902b63bdc9fa57
Reviewed-on: https://go-review.googlesource.com/c/go/+/249962
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Loading arguments of Xchg(64) and Xadd(64) functions to registers
could be done only once.
Change-Id: Iaf0a695ec9c6a221dfa755855edb68c476978a5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/227001
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Use instructions in place of currently used defines.
Updates #36765
Change-Id: I00bb59e77b1aace549d7857cc9721ba2cb4ac6ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/220541
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Add support for Load-Reserved (LR) and Store-Conditional (SC) instructions.
Use instructions in place of currently used defines.
Updates #36765
Change-Id: I77e660639802293ece40cfde4865ac237e3308d6
Reviewed-on: https://go-review.googlesource.com/c/go/+/220540
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Also remove #define's that were previously in use.
Updates #36765
Change-Id: I90b6a8629c78f549012f3f6c5f3b325336182712
Reviewed-on: https://go-review.googlesource.com/c/go/+/220539
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Based on riscv-go port.
Updates #27532
Change-Id: If522807a382130be3c8d40f4b4c1131d1de7c9e3
Reviewed-on: https://go-review.googlesource.com/c/go/+/204632
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Intrinsify these functions to match other platforms. Update the
sequence of instructions used in the assembly implementations to
match the intrinsics.
Also, add a micro benchmark so we can more easily measure the
performance of these two functions:
name old time/op new time/op delta
And8-8 5.33ns ± 7% 2.55ns ± 8% -52.12% (p=0.000 n=20+20)
And8Parallel-8 7.39ns ± 5% 3.74ns ± 4% -49.34% (p=0.000 n=20+20)
Or8-8 4.84ns ±15% 2.64ns ±11% -45.50% (p=0.000 n=20+20)
Or8Parallel-8 7.27ns ± 3% 3.84ns ± 4% -47.10% (p=0.000 n=19+20)
By using a 'rotate then xor selected bits' instruction combined with
either a 'load and and' or a 'load and or' instruction we can
implement And8 and Or8 with far fewer instructions. Replacing
'compare and swap' with atomic instructions may also improve
performance when there is contention.
Change-Id: I28bb8032052b73ae8ccdf6e4c612d2877085fa01
Reviewed-on: https://go-review.googlesource.com/c/go/+/204277
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
CL 201765 activated calls from the runtime to functions in math/bits.
When coverage and race detection were simultaneously enabled,
this caused a crash when the covered+race-checked code in
math/bits was called from the runtime before there was even a P.
PS Win for gdlv in helping sort this out.
TODO - next CL intrinsifies the new functions in
runtime/internal/sys
TODO/Would-be-nice - Ctz64 and TrailingZeros64 are the same
function; 386.s is intrinsified; clean all that up.
Fixes#35461.
Updates #35112.
Change-Id: I750a54dba493130ad3e68a06530ede7687d41e1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/206199
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Add some simple unit tests for these atomic operations. These can't
catch all the bugs that are possible with these operations but at
least they provide some coverage.
Change-Id: I94b9f451fcc9fecdb2a1448c5357b019563ad275
Reviewed-on: https://go-review.googlesource.com/c/go/+/204317
Run-TryBot: Michael Munday <mike.munday@ibm.com>
Reviewed-by: Austin Clements <austin@google.com>
We already have Load8, And8, and Or8.
For #10958, #24543, but makes sense on its own.
Change-Id: I478529fc643edc57efdeccaae413c99edd19b2eb
Reviewed-on: https://go-review.googlesource.com/c/go/+/203283
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Since the previous CL, we will not reference static symbols by
name. Therefore no need to put them into the name lookup table.
On Linux/ARM, in runtime/internal/atomic/sys_linux_arm.s, the
kernelcas function has a definition and a reference written in
two different forms, one with package prefix, one without. This
way, the assembler cannot know they are the same symbol, only the
linker knows. This is quite unusual, unify the names to so the
assembler can resolve it to index.
Change-Id: Ie7223097be6a3b65f3fa43ed4575da9972ef5b69
Reviewed-on: https://go-review.googlesource.com/c/go/+/201998
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Part 1: CL 199499 (GOOS nacl)
Part 2: CL 200077 (amd64p32 files, toolchain)
Part 3: stuff that arguably should've been part of Part 2, but I forgot
one of my grep patterns when splitting the original CL up into
two parts.
This one might also have interesting stuff to resurrect for any future
x32 ABI support.
Updates #30439
Change-Id: I2b4143374a253a003666f3c69e776b7e456bdb9c
Reviewed-on: https://go-review.googlesource.com/c/go/+/200318
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This is part two if the nacl removal. Part 1 was CL 199499.
This CL removes amd64p32 support, which might be useful in the future
if we implement the x32 ABI. It also removes the nacl bits in the
toolchain, and some remaining nacl bits.
Updates #30439
Change-Id: I2475d5bb066d1b474e00e40d95b520e7c2e286e1
Reviewed-on: https://go-review.googlesource.com/c/go/+/200077
Reviewed-by: Ian Lance Taylor <iant@golang.org>
You were a useful port and you've served your purpose.
Thanks for all the play.
A subsequent CL will remove amd64p32 (including assembly files and
toolchain bits) and remaining bits. The amd64p32 removal will be
separated into its own CL in case we want to support the Linux x32 ABI
in the future and want our old amd64p32 support as a starting point.
Updates #30439
Change-Id: Ia3a0c7d49804adc87bf52a4dea7e3d3007f2b1cd
Reviewed-on: https://go-review.googlesource.com/c/go/+/199499
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
CL 179862 introduced go:linkname directives to create ABI wrappers for
Store and Store64 on s390x, but a concurrent change (CL 180439)
replaced the Go definitions of these functions with assembly
definitions. This resulted in conflicting definitions for the ABI0
symbols, which led to a bootstrap linking failure.
Fix this by removing the now-incorrect go:linkname directives for
Store and Store64. This should fix the linux-s390x builders.
Updates #31230.
Change-Id: I8de8c03c23412fc217d428c0018cc56eb2f9996f
Reviewed-on: https://go-review.googlesource.com/c/go/+/181078
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Somehow I missed these two functions in CL 179863. This should fix the
linux-arm builders.
Updates #31230.
Change-Id: I3f8bef3fac331b505a55c0850b0fbc799b7c06c5
Reviewed-on: https://go-review.googlesource.com/c/go/+/181077
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This marks all Go symbols called from assembly in other packages with
"go:linkname" directives to ensure they get ABI wrappers.
Now that we have this go:linkname convention, this also removes the
abi0Syms definition in the runtime, which was used to give morestackc
an ABI0 wrapper. Instead, we now just mark morestackc with a
go:linkname directive.
This was tested with buildall.bash in the default configuration, with
-race, and with -gcflags=all=-d=ssa/intrinsics/off. Since I couldn't
test cgo on non-Linux configurations, I manually grepped for runtime
symbols in runtime/cgo.
Updates #31230.
Change-Id: I6c8aa56be2ca6802dfa2bf159e49c411b9071bf1
Reviewed-on: https://go-review.googlesource.com/c/go/+/179862
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
The z/Architecture does not guarantee that a load following a store
will not be reordered with that store, unless they access the same
address. Therefore if we want to ensure the sequential consistency
of atomic loads and stores we need to perform serialization
operations after atomic stores.
We do not need to serialize in the runtime when using StoreRel[ease]
and LoadAcq[uire]. The z/Architecture already provides sufficient
ordering guarantees for these operations.
name old time/op new time/op delta
AtomicLoad64-16 0.51ns ± 0% 0.51ns ± 0% ~ (all equal)
AtomicStore64-16 0.51ns ± 0% 0.60ns ± 9% +16.47% (p=0.000 n=17+20)
AtomicLoad-16 0.51ns ± 0% 0.51ns ± 0% ~ (all equal)
AtomicStore-16 0.51ns ± 0% 0.60ns ± 9% +16.50% (p=0.000 n=18+20)
Fixes#32428.
Change-Id: I88d19a4010c46070e4fff4b41587efe4c628d4d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/180439
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Shorten some of the longest tests that run during all.bash.
Removes 7r 50u 21s from all.bash.
After this change, all.bash is under 5 minutes again on my laptop.
For #26473.
Change-Id: Ie0460aa935808d65460408feaed210fbaa1d5d79
Reviewed-on: https://go-review.googlesource.com/c/go/+/177559
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
sys.HugePageSize was superceded in the last commit by physHugePageSize
which is determined dynamically by querying the operating system.
For #30333.
Change-Id: I827bfca8bdb347e989cead31564a8fffe56c66ff
Reviewed-on: https://go-review.googlesource.com/c/go/+/173757
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Like GOOS=android which implies the "linux" build tag, GOOS=illumos
implies the "solaris" build tag. This lets the existing ecosystem of
packages still work on illumos, but still permits packages to start
differentiating between solaris and illumos.
Fixes#20603
Change-Id: I8f4eabf1a66060538dca15d7658c1fbc6c826622
Reviewed-on: https://go-review.googlesource.com/c/go/+/174457
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The //go:noescape directive says that arguments don't leak at all,
which is too aggressive of a claim for functions that return pointers
derived from their parameters.
Remove the directive for now. Long term fix will require a new
directive that allows more fine-grained control over escape analysis
information supplied for functions implemented in assembly.
Also, update the BAD comments in the test cases for Loadp: we really
want that *ptr leaks to the result parameter, not that *ptr leaks to
the heap.
Updates #31525.
Change-Id: Ibfa61f2b70daa7ed3223056b57eeee777eef2e31
Reviewed-on: https://go-review.googlesource.com/c/go/+/172578
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Same as CL 170323, but for s390x instead of wasm.
Fixes#31495.
Change-Id: Ie39f649f5e33690375a8bcb1bc3b92d912ca4398
Reviewed-on: https://go-review.googlesource.com/c/go/+/172417
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Package unsafe's safety rules require that pointers converted to
uintptr must be converted back to pointer-type before being stored
into memory. In particular, storing a pointer into a non-pointer-typed
expression does not guarantee the pointer stays valid, even if the
expression refers to a pointer-typed variable.
wasm's StorepNoWB implementation violates these rules by storing a
pointer through a uintptr-typed expression.
This happens to work today because esc.go is lenient in its
implementation of package unsafe's rules, but my escape analysis
rewrite follows them more rigorously, which causes val to be treated
as a non-leaking parameter.
This CL fixes the issue by using a *T-typed expression, where T is
marked //go:notinheap so that the compiler still omits the write
barrier as appropriate.
Updates #23109.
Change-Id: I49bc5474dbaa95729e5c93201493afe692591bc8
Reviewed-on: https://go-review.googlesource.com/c/go/+/170323
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This commit allows to cross-compiling aix/ppc64. The nosplit limit must
twice as large as on others platforms because of AIX syscalls.
The stack limit, especially stackGuardMultiplier, was set by cmd/dist
during the bootstrap and doesn't depend on GOOS/GOARCH target.
Fixes#29572
Change-Id: Id51e38885e1978d981aa9e14972eaec17294322e
Reviewed-on: https://go-review.googlesource.com/c/157117
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
zgoos_aix.go is missing GoosJs, the order of GoosAndroid and GoosAix is
mixed up in all files and GoosHurd was added after CL 146023 introduced
GOOS=hurd.
Change-Id: I7e2f5a15645272e9020cfca86e44c364fc072a2b
Reviewed-on: https://go-review.googlesource.com/c/147397
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This change creates the infrastructure for new lightweight atomics
primitives in runtime/internal/atomic:
- LoadAcq, for load-acquire
- StoreRel, for store-release
- CasRel, for Compare-and-Swap-release
and implements them for ppc64x. There is visible performance improvement
in producer-consumer scenarios, like BenchmarkChanProdCons*:
benchmark old ns/op new ns/op delta
BenchmarkChanProdCons0-48 2034 2034 +0.00%
BenchmarkChanProdCons10-48 1798 1608 -10.57%
BenchmarkChanProdCons100-48 1596 1585 -0.69%
BenchmarkChanProdConsWork0-48 2084 2046 -1.82%
BenchmarkChanProdConsWork10-48 1829 1668 -8.80%
BenchmarkChanProdConsWork100-48 1650 1650 +0.00%
Fixes#21348
Change-Id: I1f6ce377e4a0fe4bd7f5f775e8036f50070ad8db
Reviewed-on: https://go-review.googlesource.com/c/142277
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Add generic, 386 and amd64 specific ops and SSA rules for multiplication
with overflow and branching based on overflow flags. Use these to intrinsify
runtime/internal/math.MulUinptr.
On amd64
mul, overflow := math.MulUintptr(a, b)
if overflow {
is lowered to two instructions:
MULQ SI
JO 0x10ee35c
No codegen tests as codegen can not currently test unexported internal runtime
functions.
amd64:
name old time/op new time/op delta
MulUintptr/small 1.16ns ± 5% 0.88ns ± 6% -24.36% (p=0.000 n=19+20)
MulUintptr/large 10.7ns ± 1% 1.1ns ± 1% -89.28% (p=0.000 n=17+19)
Change-Id: If60739a86f820e5044d677276c21df90d3c7a86a
Reviewed-on: https://go-review.googlesource.com/c/141820
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This CL adds a new internal math package for use by the runtime.
The new package exports a MulUintptr function with uintptr arguments
a and b and returns uintptr(a*b) and whether the full-width product
x*y does overflow the uintptr value range (uintptr(x*y) != x*y).
Uses of MulUinptr in the runtime and intrinsics for performance
will be added in followup CLs.
Updates #21588
Change-Id: Ia5a02eeabc955249118e4edf68c67d9fc0858058
Reviewed-on: https://go-review.googlesource.com/c/91755
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This is the first commit of a series that will add AIX as an
operating system target for ppc64 architecture.
Updates #25893
Change-Id: I865b67a9c98277c11c1a56107be404ac5253277d
Reviewed-on: https://go-review.googlesource.com/138115
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
sys here is runtime/internal/sys.
Replace uses of sys.CacheLineSize for padding by
cpu.CacheLinePad or cpu.CacheLinePadSize.
Replace other uses of sys.CacheLineSize by cpu.CacheLineSize.
Remove now unused sys.CacheLineSize.
Updates #25203
Change-Id: I1daf410fe8f6c0493471c2ceccb9ca0a5a75ed8f
Reviewed-on: https://go-review.googlesource.com/126601
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
ARMv8.1 has added new instruction (LDADDAL) for atomic memory operations. This
CL improves existing atomic add intrinsics with the new instruction. Since the
new instruction is only guaranteed to be present after ARMv8.1, we guard its
usage with a conditional on CPU feature.
Performance result on ARMv8.1 machine:
name old time/op new time/op delta
Xadd-224 1.05µs ± 6% 0.02µs ± 4% -98.06% (p=0.000 n=10+8)
Xadd64-224 1.05µs ± 3% 0.02µs ±13% -98.10% (p=0.000 n=9+10)
[Geo mean] 1.05µs 0.02µs -98.08%
Performance result on ARMv8.0 machine:
name old time/op new time/op delta
Xadd-46 538ns ± 1% 541ns ± 1% +0.62% (p=0.000 n=9+9)
Xadd64-46 505ns ± 1% 508ns ± 0% +0.48% (p=0.003 n=9+8)
[Geo mean] 521ns 524ns +0.55%
Change-Id: If4b5d8d0e2d6f84fe1492a4f5de0789910ad0ee9
Reviewed-on: https://go-review.googlesource.com/81877
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Each URL was manually verified to ensure it did not serve up incorrect
content.
Change-Id: I4dc846227af95a73ee9a3074d0c379ff0fa955df
Reviewed-on: https://go-review.googlesource.com/115798
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
This is a follow-up of CL 93637. There, when we redirect sync/atomic
to runtime/internal/atomic, a few good implementations of ARM atomics
were lost. This CL brings most of them back, with some improvements.
- Change atomic Store to a plain store with memory barrier, as we
already changed atomic Load to plain load with memory barrier.
- Use native 64-bit atomics on ARMv7, jump to Go implementations
on older machines. But drop the kernel helper. In particular,
for Load64, just do loads, not using Cas on the address being
load from, so it works also for read-only memory (since we have
already fixed 32-bit Load).
Change-Id: I725cd65cf945ae5200db81a35be3f251c9f7af14
Reviewed-on: https://go-review.googlesource.com/111315
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
This gets us around the kernel helpers on ARMv7.
It is slightly faster than using the kernel helper.
name old time/op new time/op delta
AtomicLoad-4 72.5ns ± 0% 69.5ns ± 0% -4.08% (p=0.000 n=9+9)
AtomicStore-4 57.6ns ± 1% 54.4ns ± 0% -5.58% (p=0.000 n=10+9)
[Geo mean] 64.6ns 61.5ns -4.83%
If performance is really critical, we can even do compiler intrinsics
on GOARM=7.
Fixes#23792.
Change-Id: I36497d880890b26bdf01e048b542bd5fd7b17d23
Reviewed-on: https://go-review.googlesource.com/94076
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The implementation of atomics are inherently tricky. It would
be good to have them implemented in a single place, instead of
multiple copies.
Mostly a simple redirect.
On 386, some functions in sync/atomic have better implementations,
which are moved to runtime/internal/atomic.
On ARM, some functions in sync/atomic have better implementations.
They are dropped by this CL, but restored with an improved
version in a follow-up CL. On linux/arm, 64-bit CAS kernel helper
is dropped, as we're trying to move away from kernel helpers.
Fixes#23778.
Change-Id: Icb9e1039acc92adbb2a371c34baaf0b79551c3ea
Reviewed-on: https://go-review.googlesource.com/93637
Reviewed-by: Austin Clements <austin@google.com>
There are several things combined in this change.
First, eliminate the gobitvector type in favor
of adding a ptrbit method to bitvector.
In non-performance-critical code, use that method.
In performance critical code, though, load the bitvector data
one byte at a time and iterate only over set bits.
To support that, add and use sys.Ctz8.
name old time/op new time/op delta
StackCopyPtr-8 81.8ms ± 5% 78.9ms ± 3% -3.58% (p=0.000 n=97+96)
StackCopy-8 65.9ms ± 3% 62.8ms ± 3% -4.67% (p=0.000 n=96+92)
StackCopyNoCache-8 105ms ± 3% 102ms ± 3% -3.38% (p=0.000 n=96+95)
Change-Id: I00b80f45612708bd440b1a411a57fa6dfa24aa74
Reviewed-on: https://go-review.googlesource.com/109716
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>