Unroll s == "ab" to
len(s) == 2 && s[0] == 'a' && s[1] == 'b'
This generates faster and shorter code
by avoiding a runtime call.
Do something similar for !=.
The cutoff length is 6. This was chosen empirically
by examining binary sizes on arm, arm64, 386, and amd64
using the SSA backend.
For all architectures examined, 4, 5, and 6 were
the ideal cutoff, with identical binary sizes.
The distribution of constant string equality sizes
during 'go build -a std' is:
40.81% 622 len 0
14.11% 215 len 4
9.45% 144 len 1
7.81% 119 len 3
7.48% 114 len 5
5.12% 78 len 7
4.13% 63 len 2
3.54% 54 len 8
2.69% 41 len 6
1.18% 18 len 10
0.85% 13 len 9
0.66% 10 len 14
0.59% 9 len 17
0.46% 7 len 11
0.26% 4 len 12
0.20% 3 len 19
0.13% 2 len 13
0.13% 2 len 15
0.13% 2 len 16
0.07% 1 len 20
0.07% 1 len 23
0.07% 1 len 33
0.07% 1 len 36
A cutoff of length 6 covers most of the cases.
Benchmarks on amd64 comparing a string to a constant of length 3:
Cmp/1same-8 4.78ns ± 6% 0.94ns ± 9% -80.26% (p=0.000 n=20+20)
Cmp/1diffbytes-8 6.43ns ± 6% 0.96ns ±11% -85.13% (p=0.000 n=20+20)
Cmp/3same-8 4.71ns ± 5% 1.28ns ± 5% -72.90% (p=0.000 n=20+20)
Cmp/3difffirstbyte-8 6.33ns ± 7% 1.27ns ± 7% -79.90% (p=0.000 n=20+20)
Cmp/3difflastbyte-8 6.34ns ± 8% 1.26ns ± 9% -80.13% (p=0.000 n=20+20)
The change to the prove test preserves the
existing intent of the test. When the string was
short, there was a new "proved in bounds" report
that referred to individual byte comparisons.
Change-Id: I593ac303b0d11f275672090c5c786ea0c6b8da13
Reviewed-on: https://go-review.googlesource.com/26758
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
staticassign unwraps all CONVNOPs.
However, in the included test, we need the
CONVNOP for everything to typecheck.
Stop unwrapping unnecessarily.
The code we generate for this example is
suboptimal, but that's not new; see #17113.
Fixes#17111.
Change-Id: I29532787a074a6fe19a5cc53271eb9c84bf1b576
Reviewed-on: https://go-review.googlesource.com/29213
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
After the removal of the old backend many types are no longer referenced
outside internal/gc. Make these functions private so that tools like
honnef.co/go/unused can spot when they become dead code. In doing so
this CL identified several previously public helpers which are no longer
used, so removes them.
This should be the last of the public functions.
Change-Id: I7e9c4e72f86f391b428b9dddb6f0d516529706c3
Reviewed-on: https://go-review.googlesource.com/29134
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Instead of dumping information for the use
to copy/paste into the issue tracker,
open the issue tracker directly with a pre-filled
template.
Change-Id: I370d0063b609200497014ccda35244fa4314a662
Reviewed-on: https://go-review.googlesource.com/29210
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Consistently use int16 for [ft]reg and int64 for [ft]offset.
Change-Id: I7d279bb6e4fb735105429234a949074bf1cefb29
Reviewed-on: https://go-review.googlesource.com/29215
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
These are no longer reachable as gins dispatches to ginscon for all
arch-specific instructions anyway.
Change-Id: I7f34883c16058308d8afa0f960dcf554af31bfe4
Reviewed-on: https://go-review.googlesource.com/29211
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
After the removal of the old backend many types are no longer referenced
outside internal/gc. Make these functions private so that tools like
honnef.co/go/unused can spot when they become dead code. In doing so
this CL identified several previously public helpers which are no longer
used, so removes them.
Change-Id: Idc2d485f493206de9d661bd3cb0ecb4684177b32
Reviewed-on: https://go-review.googlesource.com/29133
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
It's not everything, but it is a good start.
I tried to make the CL delete only. goimports forced
a few exceptions to that rule.
Update #16357
Change-Id: I041925cb2fe68bb7ae1617af862b22c48da649c1
Reviewed-on: https://go-review.googlesource.com/29168
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Martin Möhrmann <martisch@uos.de>
Get rid of BlockCheck. Josh goaded me into it, and I went
down a rabbithole making it happen.
NilCheck now panics if the pointer is nil and returns void, as before.
BlockCheck is gone, and NilCheck is no longer a Control value for
any block. It just exists (and deadcode knows not to throw it away).
I rewrote the nilcheckelim pass to handle this case. In particular,
there can now be multiple NilCheck ops per block.
I moved all of the arch-dependent nil check elimination done as
part of ssaGenValue into its own proper pass, so we don't have to
duplicate that code for every architecture.
Making the arch-dependent nil check its own pass means I needed
to add a bunch of flags to the opcode table so I could write
the code without arch-dependent ops everywhere.
Change-Id: I419f891ac9b0de313033ff09115c374163416a9f
Reviewed-on: https://go-review.googlesource.com/29120
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
We will soon add dedicated builders for running vet/all.
Their name will end with "-vetall".
On those builders, run vet/all and nothing else.
On all other builders, including local all.bash,
don't run vet/all at all, because it is slow.
This will probably be refined more over time.
Change-Id: Ib1d0337adda84353931a325515c132068d4320cd
Reviewed-on: https://go-review.googlesource.com/28962
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
when not instrumenting:
- Intrinsify uses of slicebytetostringtmp within the runtime package
in the ssa backend.
- Pass OARRAYBYTESTRTMP nodes to the compiler backends for lowering
instead of generating calls to slicebytetostringtmp.
name old time/op new time/op delta
ConcatStringAndBytes-4 27.9ns ± 2% 24.7ns ± 2% -11.52% (p=0.000 n=43+43)
Fixes#17044
Change-Id: I51ce9c3b93284ce526edd0234f094e98580faf2d
Reviewed-on: https://go-review.googlesource.com/29017
Run-TryBot: Martin Möhrmann <martisch@uos.de>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
It is unlikely that the value of UnixNano overflow in most
use cases. However, the max date of 2262 is also within the range
where it may be of concern to some users. Rather than have each
person recompute when this overflows to validate if its okay for
their use case, we just document it as within the years 1678 and
2262, for user's convenience.
Fixes#16977
Change-Id: I4988738c147f4a6d30f8b8735c3941b75113bb16
Reviewed-on: https://go-review.googlesource.com/28478
Reviewed-by: Andrew Gerrand <adg@golang.org>
No need to test so many sizes in race mode, especially for a package
which doesn't use goroutines.
Reduces test time from 2.5 minutes to 25 seconds.
Updates #17104
Change-Id: I7065b39273f82edece385c0d67b3f2d83d4934b8
Reviewed-on: https://go-review.googlesource.com/29163
Reviewed-by: David Crawshaw <crawshaw@golang.org>
No coverage is gained by running the 1e6 versions of the test over the
1e4 versions. It just adds 140 seconds of race overhead time.
Updates #17104
Change-Id: I41408aedae34a8b1a148eebdda20269cdefffba3
Reviewed-on: https://go-review.googlesource.com/29159
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
cmd/cover, cmd/trace, and cmd/pprof all open browsers.
'go bug' will soon also open a browser.
It is time to unify the browser-handling code.
Change-Id: Iee6b443e21e938aeaaac366a1aefb1afbc7d9b2c
Reviewed-on: https://go-review.googlesource.com/29160
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Don't benchmark so many sizes during the race builder's benchmark run.
This package doesn't even use goroutines.
Cuts off 10 seconds.
Updates #17104
Change-Id: Ibb2c7272c18b9014a775949c656a5b930f197cd4
Reviewed-on: https://go-review.googlesource.com/29158
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Shave 6.5 minutes off the *-race build time.
The *-race builders run:
go test -short -race -run=^$ -benchtime=.1s -cpu=4 $PKG
... for each package with benchmarks.
The point isn't to measure the speed of the packages, but rather to
see if there are any races. (which is why a benchtime of 0.1 seconds
is used)
But running in race mode makes things slower and our benchmarks aren't
all very fast to begin with.
The regexp benchmarks in race were taking over 6.5 minutes. With this
CL, it's now 8 seconds.
Updates #17104
Change-Id: I054528d09b1568d37aac9f9b515d6ed90a5cf5b0
Reviewed-on: https://go-review.googlesource.com/29156
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Rip out the code that allows SSA to be used conditionally.
No longer exists:
ssa=0 flag
GOSSAHASH
GOSSAPKG
SSATEST
GOSSAFUNC now only controls the printing of the IR/html.
Still need to rip out all of the old backend. It should no longer be
callable after this CL.
Update #16357
Change-Id: Ib30cc18fba6ca52232c41689ba610b0a94aa74f5
Reviewed-on: https://go-review.googlesource.com/29155
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
It passed tests once, if anything's wrong, better to fail
sooner than later.
Change-Id: Ibb1c5db3f4c5535a4ff4681fd157db77082c5041
Reviewed-on: https://go-review.googlesource.com/28982
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The go_test_bench:* tests run:
go test -short -race -run=^$ -benchtime=.1s -cpu=4 $PKG
... on each discovered package with any tests. (The same set used for
the "go_test:*" tests)
That set was 168 packages:
$ go tool dist test -list | grep go_test: | wc -l
168
But only 76 of those have a "func Benchmark", and running each
"go_test_bench:" test and compiling it in race mode, just to do
nothing took 1-2 seconds each.
So stop doing that and filter out the useless packages earlier. Now:
$ go tool dist test -list -race | grep go_test_bench: | wc -l
76
Should save 90-180 seconds. (or maybe 45 seconds for trybots, since
they're sharded)
Updates #17104
Change-Id: I08ccb072a0dc0454ea425540ee8e74b59f83b773
Reviewed-on: https://go-review.googlesource.com/29153
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The change corrects the values of the largest float32 value (f1) and the
value of the halfway point between f1 and the next, overflow value (f2).
Fixes#17012
Change-Id: Idaf9997b69d61fafbffdb980d751c9857732e14d
Reviewed-on: https://go-review.googlesource.com/29171
Reviewed-by: Robert Griesemer <gri@golang.org>
For #17068
Change-Id: I4e3ab166f08100292b779b651a9acfbfb44a55cd
Reviewed-on: https://go-review.googlesource.com/29119
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This gets -buildmode=pie -ldflags=-linkmode=internal working on
Ubuntu 16.04.
Fixes#17068
Change-Id: Ice5036199005fb528cc58279a7f057170dc6b73d
Reviewed-on: https://go-review.googlesource.com/29118
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
While you could argue the previous wording technically said that -1 is
an acceptable way to indicate "unknown" on the client, it could be read
as ambiguous. Now it's clear that both 0 and -1 mean unknown.
Change-Id: I3bc5a3fd5afd1999e487296ec121eb548415e6b0
Reviewed-on: https://go-review.googlesource.com/29130
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Created by running 'go generate'.
That made debugging fun today.
Change-Id: I9ffe00877851f2b198275220ad6058b9005daa72
Reviewed-on: https://go-review.googlesource.com/29117
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Change-Id: I11899096c71ee0e24e902c87914601fcd7ffd7a9
Reviewed-on: https://go-review.googlesource.com/28967
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Exported is no longer used since removing the text-format exporter,
and Safe is only used within importfile so it can be made into a local
variable.
Change-Id: I92986f704d7952759c79d9243620a22c24602333
Reviewed-on: https://go-review.googlesource.com/29115
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Current code uses trees of bytes.Buffer as data representation.
Each bytes.Buffer takes 4k bytes at least, so it's waste of memory.
The change introduces trees of lazy-encoder as
alternative one which reduce allocations.
name old time/op new time/op delta
Marshal-4 64.7µs ± 2% 42.0µs ± 1% -35.07% (p=0.000 n=9+10)
name old alloc/op new alloc/op delta
Marshal-4 35.1kB ± 0% 7.6kB ± 0% -78.27% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
Marshal-4 503 ± 0% 293 ± 0% -41.75% (p=0.000 n=10+10)
Change-Id: I32b96c20b8df00414b282d69743d71a598a11336
Reviewed-on: https://go-review.googlesource.com/27030
Reviewed-by: Adam Langley <agl@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Adam Langley <agl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
If there are too few primes of the given length then it can be
impossible to generate an RSA key with n distinct primes.
This change approximates the expected number of candidate primes and
causes key generation to return an error if it's unlikely to succeed.
Fixes#16596.
Change-Id: I53b60d0cb90e2d0e6f0662befa64d13f24af51a7
Reviewed-on: https://go-review.googlesource.com/28969
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
CL 28978 (6ec993a) accidentally disabled the test (it would only
run if amd64 AND s390x, whereas it should be amd64 OR s390x).
Change-Id: I23c1ad71724ff55f5808d5896b19b62c8ec5af76
Reviewed-on: https://go-review.googlesource.com/28981
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The new SSA backend modifies the ABI slightly: R0 is now a usable
general purpose register.
Fixes#16677.
Change-Id: I367435ce921e0c7e79e021c80cf8ef5d1d1466cf
Reviewed-on: https://go-review.googlesource.com/28978
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This CL makes code like this work:
res, err := http.Get("https://фу.бар/баз")
So far, IDNA support is limited to the http1 and http2 Transports.
The http package is currently responsible for converting domain names
into Punycode before calling the net layer. The http package also has
to Punycode-ify the hostname for the Host & :authority headers for
HTTP/1 and HTTP/2, respectively.
No automatic translation from Punycode back to Unicode is performed,
per Go's historical behavior. Docs are updated where relevant. No
changes needed to the Server package. Things are already in ASCII
at that point.
No changes to the net package, at least yet.
Updates x/net/http2 to git rev 57c7820 for https://golang.org/cl/29071
Updates #13835
Change-Id: I1e9a74c60d00a197ea951a9505da5c3c3187099b
Reviewed-on: https://go-review.googlesource.com/29072
Reviewed-by: Chris Broadfoot <cbro@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Consider repeatedly adding many items to a map
and then deleting them all, as in #16070. The map
itself doesn't need to grow above the high water
mark of number of items. However, due to random
collisions, the map can accumulate overflow
buckets.
Prior to this CL, those overflow buckets were
never removed, which led to a slow memory leak.
The problem with removing overflow buckets is
iterators. The obvious approach is to repack
keys and values and eliminate unused overflow
buckets. However, keys, values, and overflow
buckets cannot be manipulated without disrupting
iterators.
This CL takes a different approach, which is to
reuse the existing map growth mechanism,
which is well established, well tested, and
safe in the presence of iterators.
When a map has accumulated enough overflow buckets
we trigger map growth, but grow into a map of the
same size as before. The old overflow buckets will
be left behind for garbage collection.
For the code in #16070, instead of climbing
(very slowly) forever, memory usage now cycles
between 264mb and 483mb every 15 minutes or so.
To avoid increasing the size of maps,
the overflow bucket counter is only 16 bits.
For large maps, the counter is incremented
stochastically.
Fixes#16070
Change-Id: If551d77613ec6836907efca58bda3deee304297e
Reviewed-on: https://go-review.googlesource.com/25049
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
