If x does not have an inverse modulo m, and a negative exponent is used,
return nil just like ModInverse does now.
Change-Id: I8fa72f7a851e8cf77c5fab529ede88408740626f
Reviewed-on: https://go-review.googlesource.com/c/go/+/170757
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This adds an internal runtime debug log. It uses per-M time-stamped
ring buffers of binary log records. On panic, these buffers are
collected, interleaved, and printed.
The entry-point to the debug log is a new "dlog" function. dlog is
designed so it can be used even from very constrained corners of the
runtime such as signal handlers or inside the write barrier.
The facility is only enabled if the debuglog build tag is set.
Otherwise, it compiles away to a no-op implementation.
The debug log format is also designed so it would be reasonable to
decode from a core dump, though this hasn't been implemented.
Change-Id: I6e2737c286358e97a0d8091826498070b95b66a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/157997
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
This change adds directives to link the res_search function in libSystem.
The corresponding Go function is then used in `lookup_darwin.go` for
resolution when cgo is disabled. This makes DNS resolution logic more
reliable as macOS has some unique quirks such as the `/etc/resolver/`
directory for specifying nameservers.
Fixes#12524
Change-Id: I367263c4951383965b3ef6491196152f78e614b1
GitHub-Last-Rev: 3c3ff6bfa7
GitHub-Pull-Request: golang/go#30686
Reviewed-on: https://go-review.googlesource.com/c/go/+/166297
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
When building as part of the bootstrap process, avoid
use of "go:linkname" applied to variables, since this
feature is ill-defined/unsupported for gccgo.
Updates #30771.
Change-Id: Id44d01b5c98d292702e5075674117518cb59e2d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/170737
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This commit adds a KeepAlive field to ListenConfig and uses it
analogously to Dialer.KeepAlive to set TCP KeepAlives per default on
Accept()
Fixes#23378
Change-Id: I57eaf9508c979e7f0e2b8c5dd8e8901f6eb27fd6
GitHub-Last-Rev: e9e035d53e
GitHub-Pull-Request: golang/go#31242
Reviewed-on: https://go-review.googlesource.com/c/go/+/170678
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Before this fix, a mistaken := in a (const/type/var) declaration
ended that declaration with an error from which the parser didn't
recover well. This low-cost change will provide a better error
message and lets the parser recover perfectly.
Fixes#31092.
Change-Id: Ic4f94dc5e29dd00b7ef6d53a80dded638e3cea80
Reviewed-on: https://go-review.googlesource.com/c/go/+/169958
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Getdirentries is implemented with the __getdirentries64 function
in libSystem.dylib. That function works, but it's on Apple's
can't-be-used-in-an-app-store-application list.
Implement Getdirentries using the underlying fdopendir/readdir_r/closedir.
The simulation isn't faithful, and could be slow, but it should handle
common cases.
Don't use Getdirentries in the stdlib, use fdopendir/readdir_r/closedir
instead (via (*os.File).readdirnames).
Fixes#30933
Update #28984
RELNOTE=yes
Change-Id: Ia6b5d003e5bfe43ba54b1e1d9cfa792cc6511717
Reviewed-on: https://go-review.googlesource.com/c/go/+/168479
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
These new calls should not prevent NOSPLIT promotion, like the old ones.
These new calls should not prevent racefuncenter/exit removal.
(The latter was already true, as the new calls are not yet lowered
to StaticCalls at the point where racefuncenter/exit removal is done.)
Add tests to make sure we don't regress (again).
Fixes#31219
Change-Id: I3fb6b17cdd32c425829f1e2498defa813a5a9ace
Reviewed-on: https://go-review.googlesource.com/c/go/+/170639
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Some var declarations return "extra expression" or "missing expression"
errors when they should return “assignment mismatch” instead. Change
the returned error messages to exhibit the desired behavior.
Fixes#30085.
Change-Id: I7189355fbb0f976d70100779db4f81a9ae64fb11
Reviewed-on: https://go-review.googlesource.com/c/go/+/161558
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
We rely on SSL certificates to verify the identity of origin servers.
If an HTTPS server redirects through a plain-HTTP URL, that hop can be
compromised. We should allow it only if the user set the -insecure
flag explicitly.
Fixes#29591
Change-Id: I00639541cca2ca034c01c464385a43b3aa8ee84f
Reviewed-on: https://go-review.googlesource.com/c/go/+/156838
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
nanomsg.org currently performs an HTTPS-to-HTTP redirect, so this case
fails after the fix for #29591.
Updates #29591
Change-Id: I6306d378ef213e98c0271258bbc6669bb33f9021
Reviewed-on: https://go-review.googlesource.com/c/go/+/170637
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
mvs.BuildList and functions that invoke it directly (UpgradeAll) now
return an *mvs.BuildListError when there is an error retrieving the
requirements for a module. This new error prints the chain of
requirements from the main module to the module where the error
occurred.
These errors come up most commonly when a go.mod file has an
unexpected module path or can't be parsed for some other reason. It's
currently difficult to debug these errors because it's not clear where
the "bad" module is required from. Tools like "go list -m" and
"go mod why" don't work without the build graph.
Fixes#30661
Change-Id: I3c9d4683dcd9a5d7c259e5e4cc7e1ee209700b10
Reviewed-on: https://go-review.googlesource.com/c/go/+/166984
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
The compiler (and race detector) don't interpret locking a file as a
synchronization operation, so we add an explicit (and redundant)
sync.Mutex to make that property clear.
The additional synchronization makes it safe to parallelize the tests
in cmd/go/internal/modfetch/coderepo_test.go, which cuts the wall time
of that test by around 50%.
Updates #30550
Change-Id: Ief3479020ebf9e0fee524a4aae5568697727c683
Reviewed-on: https://go-review.googlesource.com/c/go/+/170597
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Jay Conrod <jayconrod@google.com>
As ld on AIX doesn't keep the same layout in .text section,
-Wl,-bnoobjreoder must be passed to gcc when building a C program with a
Go archive.
Change-Id: I89b584cce43ab5792f315192b073923c10d5690e
Reviewed-on: https://go-review.googlesource.com/c/go/+/170538
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Decoder.Decode and Unmarshal actually scan the input bytes twice - the
first time to check for syntax errors and the length of the value, and
the second to perform the decoding.
It's in the second scan that we actually tokenize the bytes. Since
syntax errors aren't a possibility, we can take shortcuts.
In particular, literals such as quoted strings are very common in JSON,
so we can avoid a lot of work by special casing them.
name old time/op new time/op delta
CodeDecoder-8 10.3ms ± 1% 9.1ms ± 0% -11.89% (p=0.002 n=6+6)
UnicodeDecoder-8 342ns ± 0% 283ns ± 0% -17.25% (p=0.000 n=6+5)
DecoderStream-8 239ns ± 0% 230ns ± 0% -3.90% (p=0.000 n=6+5)
CodeUnmarshal-8 11.0ms ± 0% 9.8ms ± 0% -11.45% (p=0.002 n=6+6)
CodeUnmarshalReuse-8 10.3ms ± 0% 9.0ms ± 0% -12.72% (p=0.004 n=5+6)
UnmarshalString-8 104ns ± 0% 92ns ± 0% -11.35% (p=0.002 n=6+6)
UnmarshalFloat64-8 93.2ns ± 0% 87.6ns ± 0% -6.01% (p=0.010 n=6+4)
UnmarshalInt64-8 74.5ns ± 0% 71.5ns ± 0% -3.91% (p=0.000 n=5+6)
name old speed new speed delta
CodeDecoder-8 189MB/s ± 1% 214MB/s ± 0% +13.50% (p=0.002 n=6+6)
UnicodeDecoder-8 40.9MB/s ± 0% 49.5MB/s ± 0% +20.96% (p=0.002 n=6+6)
CodeUnmarshal-8 176MB/s ± 0% 199MB/s ± 0% +12.93% (p=0.002 n=6+6)
Updates #28923.
Change-Id: I7a5e2aef51bd4ddf2004aad24210f6f50e01eaeb
Reviewed-on: https://go-review.googlesource.com/c/go/+/151042
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
(*mvsReqs).Required assumes that it is safe to mutate the slice
returned by (*mvsReqs).required. In most cases, that was true, but in
the case of -mod=vendor it resulted in unsynchronized (and
potentially interfering) writes to the global vendorList.
Fixes#30550
Change-Id: I99bcc2037e0182418b7dfda1002f8b540dbf3a1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/170598
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
splittests already contains most of the tests that cover explode. Add
the missing ones and skip the append test for empty results which would
otherwise lead to an "index out of range" panic.
Change-Id: I2cb922282d2676be9ef85f186513075ae17c0243
Reviewed-on: https://go-review.googlesource.com/c/go/+/170126
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This commit changes sendmsg, recvmsg to use nsendmsg, nrecvmsg on AIX.
These syscalls support the new msghdr structure (with Control
and Controllen) which is needed for golang.org/x/net.
Also define SockaddrDataLink.
Change-Id: I233fbd24f9eb86648e0d4d50c2b56da3626292d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/170537
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
On darwin/amd64 the runtime method sigctxt.fixsigcode changes SIGSEGV
signals so that they are never marked SI_USER. CL 169120 changed the
signal handler to call fixsigcode even when the signal is delivered to
a non-Go thread. This breaks TestSignalForwardingExternal, so skip it.
Change-Id: I6740fb5a8f4f854ca69793537a983a696da3b495
Reviewed-on: https://go-review.googlesource.com/c/go/+/170446
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The presence of the android_get_device_api_level symbol is used to
detect Android Q or later. Use the suggestion by Ryan Prichard and
look for it in libc.so and not in the entire program where someone
else might have defined it.
Manually tested on an Android Q amd64 emulator and arm64 Pixel.
Updates #29674
Change-Id: Iaef35d8f8910037b3690aa21f319e216a05a9a73
Reviewed-on: https://go-review.googlesource.com/c/go/+/170127
Run-TryBot: Elias Naur <mail@eliasnaur.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>
The certificates argument to verifyServerCertificate must contain
at least one certificate. Simplify the intermediate certificate
handling code accordingly.
Change-Id: I8292cdfb51f418e011d6d97f47d10b4e631aa932
Reviewed-on: https://go-review.googlesource.com/c/go/+/169657
Reviewed-by: Filippo Valsorda <filippo@golang.org>
- Respect the NETRC environment variable if set.
- Ignore lines that contain macro definitions.
- Associate the 'machine' token with only the tokens that follow (not
precede) it.
Updates #29888
Updates #26232
Change-Id: I3128b7d6da2d6492df7c864e165eea1a27384f0f
Reviewed-on: https://go-review.googlesource.com/c/go/+/161698
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
"leaking closure reference" is redundant for similar reasons as "&x
escapes to heap" for OADDR nodes: the reference itself does not
allocate, and we already report when the referenced variable is moved
to heap.
"mark escaped content" is redundant with "leaking param content".
Updates #23109.
Change-Id: I1ab599cb1e8434f1918dd80596a70cba7dc8a0cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/170321
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Add a new custom attribute to compile units containing the package name
of the package (i.e. the name after the 'package' keyword), so that
debuggers can know it when it's different from the last segment
of the package path.
Change-Id: Ieadaab6f47091aabf2f4dc42c8524452eaa6715b
Reviewed-on: https://go-review.googlesource.com/c/go/+/163677
Run-TryBot: Alessandro Arzilli <alessandro.arzilli@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
For most nodes (e.g., OPTRLIT, OMAKESLICE, OCONVIFACE), escape
analysis prints "escapes to heap" or "does not escape" to indicate
whether that node's allocation can be heap or stack allocated.
These messages are also emitted for OADDR, even though OADDR does not
actually allocate anything itself. Moreover, it's redundant because
escape analysis already prints "moved to heap" diagnostics when an
OADDR node like "&x" causes x to require heap allocation.
Because OADDR nodes don't allocate memory, my escape analysis rewrite
doesn't naturally emit the "escapes to heap" / "does not escape"
diagnostics for them. It's also non-trivial to replicate the exact
semantics esc.go uses for OADDR.
Since there are so many of these messages, I'm disabling them in this
CL by themselves. I modified esc.go to suppress the Warnl calls
without any other behavior changes, and then used a shell script to
automatically remove any ERROR messages mentioned by run.go in
"missing error" or "no match for" lines.
Fixes#16300.
Updates #23109.
Change-Id: I3993e2743c3ff83ccd0893f4e73b366ff8871a57
Reviewed-on: https://go-review.googlesource.com/c/go/+/170319
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
AVX-512 instructions that use RIP-relative addressing and require the
R bit of the EVEX prefix to be zero, i.e., instructions that use Z8-Z15 or
Z24-Z31, are incorrectly encoded by the assembler. The reason is that
the location of the offset at which the relative address is to be written
is incorrectly computed when the R bit is clear.
For example,
VMOVUPS bInitX<>+0(SB), Z0
encodes correctly to
62 f1 7c 48 10 05 66 e9 02 00
whereas
VMOVUPS bInitX<>+0(SB), Z8
encodes incorrectly to
62 71 7c 48 10 05 00 56 e9 02 00
Note the extra zero byte between the ModR/M byte (05) and the relative
address starting with 56. This error results in the first byte of the
following instruction being overwritten and typically, a program crash.
This commit fixes the issue in the same way that is fixed for VEX encoded
instructions, by simply not incrementing the offset for EVEX instructions.
Existing test code created for a similar VEX encoding issue (19518) has
been modified to also test for the issue addressed by this commit.
Fixes#31001
Change-Id: If84719ac22ebb5fb3c42ff96cd32b611ad497414
Reviewed-on: https://go-review.googlesource.com/c/go/+/168562
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Tidy the code up a little bit to move variable definitions closer
to uses, prefer early return to else branches and some other minor
tweaks.
I'd like to make some more changes to this code in the near future
and this CL should make those changes cleaner.
Change-Id: Ie7d7f2e4bb1e670347941e255c9cdc1703282db5
Reviewed-on: https://go-review.googlesource.com/c/go/+/170120
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
The bug in 29612 is that there are two similar-looking anonymous interface
types in two different packages, ./p1/ssa and ./p2/ssa:
v.(interface{ foo() }).foo()
These types should be treated differently because the unexported method
makes the types different (according to the spec).
But when generating the type descriptors for those two types, they
both have the name "interface { ssa.foo() }". They thus get the same
symbol, and the linker happily unifies them. It picks an arbitrary one
for the runtime to use, but that breaks conversions from concrete types
that have a foo method from the package which had its interface type
overwritten.
We need to encode the metadata symbol for unexported methods as package
path qualified (The same as we did in CL 27791 for struct fields).
So switching from FmtUnsigned to Fmtleft by default fixes the issue.
In case of generating namedata, FmtUnsigned is used.
The benchmark result ends up in no significant change of compiled binary
compare to the immediate parent.
Fixes#29612
Change-Id: I775aff91ae4a1bb16eb18a48d55e3b606f3f3352
Reviewed-on: https://go-review.googlesource.com/c/go/+/170157
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
As of this change, an explicit '@patch' suffix is to '-u=patch' as
'@latest' is to '-u'.
RELNOTE='go get' in module mode now supports the version suffix '@patch'.
Fixes#26812
Change-Id: Ib5eee40de640440f7470d37a574b311ef8a67f67
Reviewed-on: https://go-review.googlesource.com/c/go/+/167747
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>
LoadPackage was used to load a *load.Package for a command line
argument, after pattern expansion. It provided two special cases on
top of LoadImport. First, it ensured that "cmd/" packages in GOROOT
were installed in "$GOROOT/bin" or "$GOROOT/pkg/tool". Second, it
translated absolute paths to packages in GOROOT and GOPATH into
regular import paths.
With this change, LoadImport now ensures "cmd/" packages have the
right Target (without the need for a special case) and
search.ImportPaths translates absolute paths.
LoadPackage no longer handles these special cases and has been renamed
to LoadImportWithFlags, since it's still useful for loading implicit
dependencies.
Updates #29758
Change-Id: I9d54036f90c3ccd9b3a0fe0eaddaa7749593cc91
Reviewed-on: https://go-review.googlesource.com/c/go/+/167748
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
They were previously indented at the same level as the normal text when
printing a single symbol or the description of a field.
Running "go doc text/template Must":
Before:
func Must(t *Template, err error) *Template
Must is a helper that wraps a call to a function returning (*Template,
error) and panics if the error is non-nil. It is intended for use in
variable initializations such as
var t = template.Must(template.New("name").Parse("text"))
After:
func Must(t *Template, err error) *Template
Must is a helper that wraps a call to a function returning (*Template,
error) and panics if the error is non-nil. It is intended for use in
variable initializations such as
var t = template.Must(template.New("name").Parse("text"))
Running "go doc http Request.Header":
Before:
type Request struct {
// Header contains the request header fields either received
// by the server or to be sent by the client.
//
// If a server received a request with header lines,
//
// Host: example.com
// accept-encoding: gzip, deflate
// Accept-Language: en-us
// fOO: Bar
// foo: two
//
// then
//
// Header = map[string][]string{
// "Accept-Encoding": {"gzip, deflate"},
// "Accept-Language": {"en-us"},
// "Foo": {"Bar", "two"},
// }
...
After:
type Request struct {
// Header contains the request header fields either received by the server or
// to be sent by the client.
//
// If a server received a request with header lines,
//
// Host: example.com
// accept-encoding: gzip, deflate
// Accept-Language: en-us
// fOO: Bar
// foo: two
//
// then
//
// Header = map[string][]string{
// "Accept-Encoding": {"gzip, deflate"},
// "Accept-Language": {"en-us"},
// "Foo": {"Bar", "two"},
// }
...
Fixes#29708
Change-Id: Ibe1a6a7a76d6b19c5737ba6e8210e3ad0b88ce16
GitHub-Last-Rev: 439c0fe70a
GitHub-Pull-Request: golang/go#31120
Reviewed-on: https://go-review.googlesource.com/c/go/+/169957
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
This is a follow-up CL to https://golang.org/cl/170118, updating a comment made
incorrect by that CL.
Change-Id: I5a29cfae331fbbbb36c96d96f9e4949393a5942d
Reviewed-on: https://go-review.googlesource.com/c/go/+/170123
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Currently the shift amount is only masked on x86. Change it so it
is masked on all architectures. In the worst case we generate a
couple of extra instructions to perform the masking and in the best
case we can elide overflow checks.
This particular shift could also be replaced with a rotate
instruction during optimization which would remove both the masking
instructions and overflow checks on all architectures.
Fixes#31165.
Change-Id: I16b7a8800b4ba8813dc83735dfc59564e661d3b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/170122
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The first biggest offender was crypto/des.init at ~1%. It's
cryptographically broken and the init function is relatively expensive,
which is unfortunate as both crypto/tls and crypto/x509 (and by
extension, cmd/go) import it. Hide the work behind sync.Once.
The second biggest offender was flag.sortFlags at just under 1%, used by
the Visit flagset methods. It allocated two slices, which made a
difference as cmd/go iterates over multiple flagsets during init.
Use a single slice with a direct sort.Interface implementation.
Another big offender is initializing global maps. Reducing this work in
cmd/go/internal/imports and net/textproto gives us close to another
whole 1% in saved work. The former can use map literals, and the latter
can hide the work behind sync.Once.
Finally, compress/flate used newHuffmanBitWriter as part of init, which
allocates many objects and slices. Yet it only used one of the slice
fields. Allocating just that slice saves a surprising ~0.3%, since we
generated a lot of unnecessary garbage.
All in all, these little pieces amount to just over 3% saved CPU time.
name old time/op new time/op delta
ExecGoEnv-8 3.61ms ± 1% 3.50ms ± 0% -3.02% (p=0.000 n=10+10)
Updates #26775.
Updates #29382.
Change-Id: I915416e88a874c63235ba512617c8aef35c0ca8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/166459
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
When branching at a bounds check for indexing or slicing ops, prove currently
only learns from the upper bound. On the positive branch, we currently learn
i < len(a) (or i <= len(a)) in both the signed and unsigned domains.
This CL makes prove also learn from the lower bound. Specifically, on the
positive branch from index or slicing ops, prove will now ALSO learn i >= 0 in
the signed domain (this fact is of no value in the unsigned domain).
The substantive change itself is only an additional call to addRestrictions,
though I've also inverted the nested switch statements around that call for the
sake of clarity.
This CL removes 92 bounds checks from std and cmd. It passes all tests and
shows no deltas on compilecmp.
Fixes#28885
Change-Id: I13eccc36e640eb599fa6dc5aa3be3c7d7abd2d9e
Reviewed-on: https://go-review.googlesource.com/c/go/+/170121
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
In CL 169960 I didn't realize that we also have race detector support for arm64.
Change-Id: If77bfb0f700a04c04416dad61ef11e27b1c98e07
Reviewed-on: https://go-review.googlesource.com/c/go/+/170105
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Prove requires access to a zero-valued constant in multiple heavily-used
code paths. Currently, prove is checking for the existence of the constant on
every iteration of these paths, and creating it if not found.
This CL preempts all of these checks by finding or creating the zero constant
Value, just once, when the factsTable is initialised on entry to prove(). The
Method used to initialise the zero constant, func.ConstInt64(), finds an
existing constant if present, or creates one in the entry block otherwise.
Fixes#31141
Change-Id: Ic9a2fd9d79b67025e24d4483f6e87cf8213ead24
Reviewed-on: https://go-review.googlesource.com/c/go/+/170118
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
