1
0
mirror of https://github.com/golang/go synced 2024-11-20 05:34:40 -07:00
Commit Graph

28338 Commits

Author SHA1 Message Date
griesemer
4b7325c7e3 cmd/compile/internal/syntax: cleanups around parser tracing
These changes affect the parser only when the internal trace
constant is set.

- factored our printing code used for tracing
- streamlined advance function and added trace output

The parser's trace output now more clearly prints what tokens
are skipped and which is the next token in case of an error.

Example trace:

    4: . . . . . . . . . . call (
    4: . . . . . . . . . . . expr (
    4: . . . . . . . . . . . . unaryExpr (
    4: . . . . . . . . . . . . . pexpr (
    4: . . . . . . . . . . . . . . operand name (
    4: . . . . . . . . . . . . . . )
    4: . . . . . . . . . . . . . . call (
    4: . . . . . . . . . . . . . . )
    4: . . . . . . . . . . . . . )
    4: . . . . . . . . . . . . )
    4: . . . . . . . . . . . )
    4: . . . . . . . . . . . syntax error: expecting comma or )
    4: . . . . . . . . . . . skip ;
    6: . . . . . . . . . . . skip name
    6: . . . . . . . . . . . skip :=
    6: . . . . . . . . . . . skip literal
    6: . . . . . . . . . . . skip ;
    7: . . . . . . . . . . . skip }
    7: . . . . . . . . . . . skip ;
    9: . . . . . . . . . . . skip func
    9: . . . . . . . . . . . skip name
    9: . . . . . . . . . . . skip (
    9: . . . . . . . . . . . next )
    9: . . . . . . . . . . )

For #22164.

Change-Id: I4a233696b1f989ee3287472172afaf92cf424565
Reviewed-on: https://go-review.googlesource.com/70490
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-16 17:18:08 +00:00
Ian Lance Taylor
5ddd3d588c runtime: fix use of STREX in various exitThread implementations
STREX does not permit using the same register for the value to store
and the place where the result is returned. Also the code was wrong
anyhow if the first store failed.

Fixes #22248

Change-Id: I96013497410058514ffcb771c76c86faa1ec559b
Reviewed-on: https://go-review.googlesource.com/70911
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-16 17:15:39 +00:00
Kunpei Sakai
001fe1d57a net/http/httputil: extract duplicate code as removeConnectionHeaders
Change-Id: I50389752dcbf5d058ce11256a414be7955cdb77f
Reviewed-on: https://go-review.googlesource.com/71070
Run-TryBot: Tom Bergan <tombergan@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tom Bergan <tombergan@google.com>
2017-10-16 17:09:55 +00:00
soluchok
eb695819a5 net/http: fix panic when status without description for proxied HTTPS responses
Check to ensure that Status is set
when parsing a proxied HTTPS response
that a CONNECT proxy-authorization.

Fixes #21701

Change-Id: Id91700b83425420101e0b0d46e12aaf5d20fd3a3
Reviewed-on: https://go-review.googlesource.com/59990
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Tom Bergan <tombergan@google.com>
2017-10-16 16:46:20 +00:00
Michael Hudson-Doyle
302f0d1646 cmd/link: replace SCONTAINER with an attribute bit
This is much easier than replacing SSUB so split it out from my other CL.

Change-Id: If01e4005da5355895404456320a2156bde4ec09a
Reviewed-on: https://go-review.googlesource.com/71050
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-16 06:40:37 +00:00
Michael Hudson-Doyle
1341104ae2 cmd/link: replace SHIDDEN bit in SymKind with a bit of Attribute
This is https://go-review.googlesource.com/42025 but with some more fixes --
hidden symbols implicitly passed "Type == 0 || Type == SXREF" checks. (This
sort of thing is part of why I wanted to make this change)

Change-Id: I2273ee98570fd7f2dd8a799c692a2083c014235e
Reviewed-on: https://go-review.googlesource.com/42330
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-16 06:40:13 +00:00
Javier Segura
7128ed0501 bytes: add examples of Equal and IndexByte
Change-Id: Ibf3179d0903eb443c89b6d886802c36f8d199898
Reviewed-on: https://go-review.googlesource.com/70933
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-16 03:34:28 +00:00
Daniel Martí
270a789c52 cmd/compile: simplify some declarations
Reduce the scope of some. Also remove vars that were simply the index or
the value in a range statement. While at it, remove a var that was
exactly the length of a slice.

Also replaced 'bad' with a more clear 'errored' of type bool, and
renamed a single-char name with a comment to a name that is
self-explanatory.

And removed a few unnecessary Index calls within loops.

Passes toolstash -cmp on std cmd.

Change-Id: I26eee5f04e8f7e5418e43e25dca34f89cca5c80a
Reviewed-on: https://go-review.googlesource.com/70930
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-15 19:24:40 +00:00
Rob Pike
e5b7335705 fmt: clarify wording of * flag
The complainant is confused by the ambiguity of 'next' in the
phrase 'next operand'. It seems clear enough to me that things
are always read left to right when formatting, but to calm the
waters we add a clarifying parenthetical.

Fixes #22275

Change-Id: I82418c1e987db736f4bee0faa53fe715c9cde8f5
Reviewed-on: https://go-review.googlesource.com/71010
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
2017-10-15 06:03:34 +00:00
Andreas Auernhammer
fb46b9ea20 crypto/elliptic: don't unmarshal invalid encoded points
ANSI X9.62 specifies that Unmarshal should fail if the a given coordinate is
not smaller than the prime of the elliptic curve. This change makes Unmarshal
ANSI X9.62 compliant and explicitly documents that the Marshal/Unmarshal only
supports uncompressed points.

Fixes #20482

Change-Id: I161a73da8279cae505c9ba0b3022021709fe8145
Reviewed-on: https://go-review.googlesource.com/44312
Reviewed-by: Adam Langley <agl@golang.org>
Reviewed-by: Filippo Valsorda <hi@filippo.io>
Run-TryBot: Adam Langley <agl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-15 02:24:19 +00:00
Jed Denlea
8b220d8ef1 image/gif: write fewer, bigger blocks
The indexed bitmap of a frame is encoded into a GIF by first LZW
compression, and then packaged by a simple block mechanism.  Each block
of up-to-256 bytes starts with one byte, which indicates the size of the
block (0x01-0xff). The sequence of blocks is terminated by a 0x00.

While the format supports it, there is no good reason why any particular
image should be anything but a sequence of 255-byte blocks with one last
block less than 255-bytes.

The old blockWriter implementation would not buffer between Write()s,
meaning if the lzw Writer needs to flush more than one chunk of data via
a Write, multiple short blocks might exist in the middle of a stream.

Separate but related, the old implementation also forces lzw.NewWriter
to allocate a bufio.Writer because the blockWriter is not an
io.ByteWriter itself.  But, even though it doesn't effectively buffer
data between Writes, it does make extra copies of sub-blocks during the
course of writing them to the GIF's writer.

Now, the blockWriter shall continue to use the encoder's [256]byte buf,
but use it to effectively buffer a series of WriteByte calls from the
lzw Writer.  Once a WriteByte fills the buffer, the staged block is
Write()n to the underlying GIF writer.  After the lzw Writer is Closed,
the blockWriter should also be closed, which will flush any remaining
block along with the block terminator.

BenchmarkEncode indicates slight improvements:

name      old time/op    new time/op    delta
Encode-8    7.71ms ± 0%    7.38ms ± 0%   -4.27%  (p=0.008 n=5+5)

name      old speed      new speed      delta
Encode-8   159MB/s ± 0%   167MB/s ± 0%   +4.46%  (p=0.008 n=5+5)

name      old alloc/op   new alloc/op   delta
Encode-8    84.1kB ± 0%    80.0kB ± 0%   -4.94%  (p=0.008 n=5+5)

name      old allocs/op  new allocs/op  delta
Encode-8      9.00 ± 0%      7.00 ± 0%  -22.22%  (p=0.008 n=5+5)

Change-Id: I9eb9367d41d7c3d4d7f0adc9b720fc24fb50006a
Reviewed-on: https://go-review.googlesource.com/68351
Reviewed-by: Nigel Tao <nigeltao@golang.org>
2017-10-14 05:51:20 +00:00
Matthew Dempsky
f3d4ff7ddc cmd/compile: omit ICE diagnostics after normal error messages
After we detect errors, the AST is in a precarious state and more
likely to trip useless ICE failures. Instead let the user fix any
existing errors and see if the ICE persists.  This makes Fatalf more
consistent with how panics are handled by hidePanic.

While here, also fix detection for release versions: release version
strings begin with "go" ("go1.8", "go1.9.1", etc), not "release".

Fixes #22252.

Change-Id: I1c400af62fb49dd979b96e1bf0fb295a81c8b336
Reviewed-on: https://go-review.googlesource.com/70850
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-10-14 01:00:31 +00:00
Cherry Zhang
e01eac371a cmd/compile: mark LoweredGetCallerPC rematerializeable
The caller's PC is always available in the frame. We can just
load it when needed, no need to spill.

Change-Id: I9c0a525903e574bb4eec9fe53cbeb8c64321166a
Reviewed-on: https://go-review.googlesource.com/70710
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-10-14 00:53:20 +00:00
Peter Wu
d1bbdbe760 crypto/tls: replace signatureAndHash by SignatureScheme.
Consolidate the signature and hash fields (SignatureAndHashAlgorithm in
TLS 1.2) into a single uint16 (SignatureScheme in TLS 1.3 draft 21).
This makes it easier to add RSASSA-PSS for TLS 1.2 in the future.

Fields were named like "signatureAlgorithm" rather than
"signatureScheme" since that name is also used throughout the 1.3 draft.

The only new public symbol is ECDSAWithSHA1, other than that this is an
internal change with no new functionality.

Change-Id: Iba63d262ab1af895420583ac9e302d9705a7e0f0
Reviewed-on: https://go-review.googlesource.com/62210
Reviewed-by: Adam Langley <agl@golang.org>
2017-10-13 23:25:03 +00:00
David Crawshaw
c996d07fee cmd/link: use the correct module data on ppc64le
Fixes #22250

Change-Id: I0e39d10ff6f0785cd22b0105de2d839e569db4b7
Reviewed-on: https://go-review.googlesource.com/70810
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-13 22:46:25 +00:00
Austin Clements
e09dbaa1de runtime: schedule fractional workers on all Ps
Currently only a single P can run a fractional mark worker at a time.
This doesn't let us spread out the load, so it gets concentrated on
whatever unlucky P picks up the token to run a fractional worker. This
can significantly delay goroutines on that P.

This commit changes this scheduling rule so each P separately
schedules fractional workers. This can significantly reduce the load
on any individual P and allows workers to self-preempt earlier. It
does have the downside that it's possible for all Ps to be in
fractional workers simultaneously (an effect STW).

Updates #21698.

Change-Id: Ia1e300c422043fa62bb4e3dd23c6232d81e4419c
Reviewed-on: https://go-review.googlesource.com/68574
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-10-13 20:53:22 +00:00
Austin Clements
28e1a8e47a runtime: preempt fractional worker after reaching utilization goal
Currently fractional workers run until preempted by the scheduler,
which means they typically run for 20ms. During this time, all other
goroutines on that P are blocked, which can introduce significant
latency variance.

This modifies fractional workers to self-preempt shortly after
achieving the fractional utilization goal. In practice this means they
preempt much sooner, and the scale of their preemption is on the order
of how often the user goroutine block (so, if the application is
compute-bound, the fractional workers will also run for long times,
but if the application blocks frequently, the fractional workers will
also preempt quickly).

Fixes #21698.
Updates #18534.

Change-Id: I03a5ab195dae93154a46c32083c4bb52415d2017
Reviewed-on: https://go-review.googlesource.com/68573
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-10-13 20:53:13 +00:00
Austin Clements
b783930e63 runtime: simplify fractional mark worker scheduler
We haven't used non-zero gcForcePreemptNS for ages. Remove it and
declutter the code.

Change-Id: Id5cc62f526d21ca394d2b6ca17d34a72959535da
Reviewed-on: https://go-review.googlesource.com/68572
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-10-13 20:53:03 +00:00
Austin Clements
315c28b788 runtime: use only dedicated mark workers at reasonable GOMAXPROCS
When GOMAXPROCS is not small, fractional workers don't add much to
throughput, but they do add to the latency of individual goroutines.
In this case, it makes sense to just use dedicated workers, even if we
can't exactly hit the 25% CPU goal with dedicated workers.

This implements this logic by computing the number of dedicated mark
workers that will us closest to the 25% target. We only fall back to
fractional workers if that would be more than 30% off of the target
(less than 17.5% or more than 32.5%, which in practice happens for
GOMAXPROCS <= 3 and GOMAXPROCS == 6).

Updates #21698.

Change-Id: I484063adeeaa1190200e4ef210193a20e635d552
Reviewed-on: https://go-review.googlesource.com/68571
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-10-13 20:52:55 +00:00
Austin Clements
27923482fa runtime: separate GC background utilization from goal utilization
Currently these are the same constant, but are separate concepts.
Split them into two constants for easier experimentation and better
documentation.

Change-Id: I121854d4fd1a4a827f727c8e5153160c24aacda7
Reviewed-on: https://go-review.googlesource.com/68570
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-10-13 20:52:45 +00:00
Adam Langley
504a305c62 crypto/x509: reformat test struct.
https://golang.org/cl/67270 wasn't `go fmt`ed correctly, according to
the current `go fmt`. However, what `go fmt` did looked odd, so this
change tweaks the test to use a more standard layout.

Whitespace-only; no semantic change.

Change-Id: Id820352e7c9e68189ee485c8a9bfece75ca4f9cb
Reviewed-on: https://go-review.googlesource.com/69031
Run-TryBot: Adam Langley <agl@golang.org>
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
Reviewed-by: Adam Langley <agl@golang.org>
2017-10-13 18:29:40 +00:00
Ben Schwartz
f5cd3868d5 net/http: HTTPS proxies support
net/http already supports http proxies. This CL allows it to establish
a connection to the http proxy over https. See more at:
https://www.chromium.org/developers/design-documents/secure-web-proxy

Fixes golang/go#11332

Change-Id: If0e017df0e8f8c2c499a2ddcbbeb625c8fa2bb6b
Reviewed-on: https://go-review.googlesource.com/68550
Run-TryBot: Tom Bergan <tombergan@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tom Bergan <tombergan@google.com>
2017-10-13 18:20:45 +00:00
Daniel Theophanes
897080d5cb database/sql: prevent race in driver by locking dc in Next
Database drivers should be called from a single goroutine to ease
driver's design. If a driver chooses to handle context
cancels internally it may do so.

The sql package violated this agreement when calling Next or
NextResultSet. It was possible for a concurrent rollback
triggered from a context cancel to call a Tx.Rollback (which
takes a driver connection lock) while a Rows.Next is in progress
(which does not tack the driver connection lock).

The current internal design of the sql package is each call takes
roughly two locks: a closemu lock which prevents an disposing of
internal resources (assigning nil or removing from lists)
and a driver connection lock that prevents calling driver code from
multiple goroutines.

Fixes #21117

Change-Id: Ie340dc752a503089c27f57ffd43e191534829360
Reviewed-on: https://go-review.googlesource.com/65731
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 18:11:41 +00:00
David Crawshaw
350b74bc4b cmd/link: zero symtab fields correctly
CL 69370 introduced a hasmain field to moduledata after the
modulehashes slice. However that code was relying on the zeroing
code after it to cover modulehashes if len(Shlibs) == 0. The
hasmain field gets in the way of that. So clear modulehashes
explicitly in that case.

Found when looking at #22250. Not sure if it's related.

Change-Id: I81050cb4554cd49e9f245d261ef422f97d026df4
Reviewed-on: https://go-review.googlesource.com/70730
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 17:48:54 +00:00
Daniel Martí
0e4de78d13 net: fix data race in TestClosingListener
In https://golang.org/cl/66334, the test was changed so that the second
Listen would also be closed. However, it shouldn't have reused the same
ln variable, as that can lead to a data race with the background loop
that accepts connections.

Simply define a new Listener, since we don't need to overwrite the first
variable.

I was able to reproduce the data race report locally about 10% of the
time by reducing the sleep from a millisecond to a nanosecond. After the
fix, it's entirely gone after 1000 runs.

Fixes #22226.

Change-Id: I7c639f9f2ee5098eac951a45f42f97758654eacd
Reviewed-on: https://go-review.googlesource.com/70230
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 15:19:59 +00:00
Martin Möhrmann
743117a85e cmd/compile: simplify slice/array range loops for some element sizes
In range loops over slices and arrays besides a variable to track the
index an extra variable containing the address of the current element
is used. To compute a pointer to the next element the elements size is
added to the address.

On 386 and amd64 an element of size 1, 2, 4 or 8 bytes can by copied
from an array using a MOV instruction with suitable addressing mode
that uses the start address of the array, the index of the element and
element size as scaling factor. Thereby, for arrays and slices with
suitable element size we can avoid keeping and incrementing an extra
variable to compute the next elements address.

Shrinks cmd/go by 4 kilobytes.

AMD64:
name                   old time/op    new time/op    delta
BinaryTree17              2.66s ± 7%     2.54s ± 0%  -4.53%  (p=0.000 n=10+8)
Fannkuch11                3.02s ± 1%     3.02s ± 1%    ~     (p=0.579 n=10+10)
FmtFprintfEmpty          45.6ns ± 1%    42.2ns ± 1%  -7.46%  (p=0.000 n=10+10)
FmtFprintfString         69.8ns ± 1%    70.4ns ± 1%  +0.84%  (p=0.041 n=10+10)
FmtFprintfInt            80.1ns ± 1%    79.0ns ± 1%  -1.35%  (p=0.000 n=10+10)
FmtFprintfIntInt          127ns ± 1%     125ns ± 1%  -1.00%  (p=0.007 n=10+9)
FmtFprintfPrefixedInt     158ns ± 2%     152ns ± 1%  -4.11%  (p=0.000 n=10+10)
FmtFprintfFloat           218ns ± 1%     214ns ± 1%  -1.61%  (p=0.000 n=10+10)
FmtManyArgs               508ns ± 1%     504ns ± 1%  -0.93%  (p=0.001 n=9+10)
GobDecode                6.76ms ± 1%    6.78ms ± 1%    ~     (p=0.353 n=10+10)
GobEncode                5.84ms ± 1%    5.77ms ± 1%  -1.31%  (p=0.000 n=10+9)
Gzip                      223ms ± 1%     218ms ± 1%  -2.39%  (p=0.000 n=10+10)
Gunzip                   40.3ms ± 1%    40.4ms ± 3%    ~     (p=0.796 n=10+10)
HTTPClientServer         73.5µs ± 0%    73.3µs ± 0%  -0.28%  (p=0.000 n=10+9)
JSONEncode               12.7ms ± 1%    12.6ms ± 8%    ~     (p=0.173 n=8+10)
JSONDecode               57.5ms ± 1%    56.1ms ± 2%  -2.40%  (p=0.000 n=10+10)
Mandelbrot200            3.80ms ± 1%    3.86ms ± 6%    ~     (p=0.579 n=10+10)
GoParse                  3.25ms ± 1%    3.23ms ± 1%    ~     (p=0.052 n=10+10)
RegexpMatchEasy0_32      74.4ns ± 1%    76.9ns ± 1%  +3.39%  (p=0.000 n=10+10)
RegexpMatchEasy0_1K       243ns ± 2%     248ns ± 1%  +1.86%  (p=0.000 n=10+8)
RegexpMatchEasy1_32      71.0ns ± 2%    72.8ns ± 1%  +2.55%  (p=0.000 n=10+10)
RegexpMatchEasy1_1K       370ns ± 1%     383ns ± 0%  +3.39%  (p=0.000 n=10+9)
RegexpMatchMedium_32      107ns ± 0%     113ns ± 1%  +5.33%  (p=0.000 n=6+10)
RegexpMatchMedium_1K     35.0µs ± 1%    36.0µs ± 1%  +3.13%  (p=0.000 n=10+10)
RegexpMatchHard_32       1.65µs ± 1%    1.69µs ± 1%  +2.23%  (p=0.000 n=10+9)
RegexpMatchHard_1K       49.8µs ± 1%    50.6µs ± 1%  +1.59%  (p=0.000 n=10+10)
Revcomp                   398ms ± 1%     396ms ± 1%  -0.51%  (p=0.043 n=10+10)
Template                 63.4ms ± 1%    60.8ms ± 0%  -4.11%  (p=0.000 n=10+9)
TimeParse                 318ns ± 1%     322ns ± 1%  +1.10%  (p=0.005 n=10+10)
TimeFormat                323ns ± 1%     336ns ± 1%  +4.15%  (p=0.000 n=10+10)

Updates: #15809.

Change-Id: I55915aaf6d26768e12247f8a8edf14e7630726d1
Reviewed-on: https://go-review.googlesource.com/38061
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-13 14:52:04 +00:00
Frank Somers
af40cbe83c runtime: use vDSO on linux/386 to improve time.Now performance
This change adds support for accelerating time.Now by using
the __vdso_clock_gettime fast-path via the vDSO on linux/386
if it is available.

When the vDSO path to the clocks is available, it is typically
5x-10x faster than the syscall path (see benchmark extract
below).  Two such calls are made for each time.Now() call
on most platforms as of go 1.9.

- Add vdso_linux_386.go, containing the ELF32 definitions
  for use by vdso_linux.go, the maximum array size, and
  the symbols to be located in the vDSO.

- Modify runtime.walltime and runtime.nanotime to check for
  and use the vDSO fast-path if available, or fall back to
  the existing syscall path.

- Reduce the stack reservations for runtime.walltime and
  runtime.monotime from 32 to 16 bytes. It appears the syscall
  path actually only needed 8 bytes, but 16 is now needed to
  cover the syscall and vDSO paths.

- Remove clearing DX from the syscall paths as clock_gettime
  only takes 2 args (BX, CX in syscall calling convention),
  so there should be no need to clear DX.

The included BenchmarkTimeNow was run with -cpu=1 -count=20
on an "Intel(R) Celeron(R) CPU J1900 @ 1.99GHz", comparing
released go 1.9.1 vs this change. This shows a gain in
performance on linux/386 (6.89x), and that no regression
occurred on linux/amd64 due to this change.

Kernel: linux/i686, GOOS=linux GOARCH=386
   name      old time/op  new time/op  delta
   TimeNow   978ns ± 0%   142ns ± 0%  -85.48%  (p=0.000 n=16+20)

Kernel: linux/x86_64, GOOS=linux GOARCH=amd64
   name      old time/op  new time/op  delta
   TimeNow   125ns ± 0%   125ns ± 0%   ~       (all equal)

Gains are more dramatic in virtualized environments,
presumably due to the overhead of virtualizing the syscall.

Fixes #22190

Change-Id: I2f83ce60cb1b8b310c9ced0706bb463c1b3aedf8
Reviewed-on: https://go-review.googlesource.com/69390
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 14:41:04 +00:00
Tobias Klauser
bf237f534c syscall: correct type for timeout argument to Select on linux/{arm64,mips64x}
syscall.Select uses SYS_PSELECT6 on arm64 and mipx64x, however this
syscall expects its 5th argument to be of type Timespec (with seconds
and nanoseconds) instead of type Timeval (with seconds and microseconds)
This leads to the timeout being too short by a factor of 1000.

This CL fixes this by adjusting the timeout argument accordingly,
similarly to how glibc does it for architectures where neither
SYS_SELECT nor SYS__NEWSELECT are available.

Fixes #22246

Change-Id: I33a183b0b87c2dae4a77a2d00f8615169fad48dd
Reviewed-on: https://go-review.googlesource.com/70590
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 14:01:17 +00:00
Wei Xiao
531e6c06c4 cmd/asm: refine Go assembly for ARM64
Some ARM64-specific instructions (such as SIMD instructions) are not supported.
This patch adds support for the following:
1. Extended register, e.g.:
     ADD	Rm.<ext>[<<amount], Rn, Rd
     <ext> can have the following values:
       UXTB, UXTH, UXTW, UXTX, SXTB, SXTH, SXTW and SXTX
2. Arrangement for SIMD instructions, e.g.:
     VADDP	Vm.<T>, Vn.<T>, Vd.<T>
     <T> can have the following values:
       B8, B16, H4, H8, S2, S4 and D2
3. Width specifier and element index for SIMD instructions, e.g.:
     VMOV	Vn.<T>[index], Rd // MOV(to general register)
     <T> can have the following values:
       S and D
4. Register List, e.g.:
     VLD1	(Rn), [Vt1.<T>, Vt2.<T>, Vt3.<T>]
5. Register offset variant, e.g.:
     VLD1.P	(Rn)(Rm), [Vt1.<T>, Vt2.<T>] // Rm is the post-index register
6. Go assembly for ARM64 reference manual
     new added instructions are required to have according explanation items in
     the manual and items for existed instructions will be added incrementally

For more information about the refinement background, please refer to the
discussion (https://groups.google.com/forum/#!topic/golang-dev/rWgDxCrL4GU)

This patch only adds syntax and doesn't break any assembly that already exists.

Change-Id: I34e90b7faae032820593a0e417022c354a882008
Reviewed-on: https://go-review.googlesource.com/41654
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-10-13 13:41:19 +00:00
Jed Denlea
31cd20a70e image/gif: try harder to use global color table
The GIF format allows for an image to contain a global color table which
might be used for some or every frame in an animated GIF.  This palette
contains 24-bit opaque RGB values.  An individual frame may use the
global palette and enable transparency by picking one number to be
transparent, instead of the color value in the palette.

image/gif decodes a GIF, which contains an []*image.Paletted that holds
each frame.  When decoded, if a frame has a transparent color and uses
the global palette, a copy of the global []color.Color is made, and the
transparency color index is replaced with color.RGBA{}.

When encoding a GIF, each frame's palette is encoded to the form it
might exist in a GIF, up to 768 bytes "RGBRGBRGBRGB...". If a frame's
encoded palette is equal to the encoded global color table, the frame
will be encoded with the flag set to use the global color table,
otherwise the frame's palette will be included.

So, if the color in the global color table that matches the transparent
index of one frame wasn't black (and it frequently is not), reencoding a
GIF will likely result in a larger file because each frame's palette
will have to be encoded inline.

This commit takes a frame's transparent color index into account when
comparing an individual image.Paletted's encoded color table to the
global color table.

Fixes #22137

Change-Id: I5460021da6e4d7ce19198d5f94a8ce714815bc08
Reviewed-on: https://go-review.googlesource.com/68313
Reviewed-by: Nigel Tao <nigeltao@golang.org>
2017-10-13 04:28:53 +00:00
David Chase
e45e490296 cmd/compile: attempt to deflake debug_test.go
Excluded when -short because it still runs relatively long,
but deflaked.

Removed timeouts from normal path and ensured that they were
not needed and that reference files did not change.

Use "tbreak" instead of "break" with gdb to reduce chance
of multiple hits on main.main.  (Seems not enough, but a
move in the right direction).

By default, testing ignores repeated lines that occur when
nexting.  This appears to sometimes be timing-dependent and
is the observed source of flakiness in testing so far.
Note that these can also be signs of a bug in the generated
debugging output, but it is one of the less-confusing bugs
that can occur.

By default, testing with gdb uses compilation with
inlining disabled to prevent dependence on library code
(it's a bug that library code is seen while Nexting, but
the bug is current behavior).

Also by default exclude all source files outside /testdata
to prevent accidental dependence on library code.  Note that
this is currently only applicable to dlv because (for the
debugging information we produce) gdb does not indicate a
change in the source file for inlined code.

Added flags -i and -r to make gdb testing compile with
inlining and be sensitive to repeats in the next stream.
This is for developer-testing and so we can describe these
problems in bug reports.

Updates #22206.

Change-Id: I9a30ebbc65aa0153fe77b1858cf19743bdc985e4
Reviewed-on: https://go-review.googlesource.com/69930
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 03:25:23 +00:00
Tim Cooper
245e386e4c reflect: allow Copy to a byte array or byte slice from a string
This somewhat mirrors the special case behavior of the copy built-in.

Fixes #22215

Change-Id: Ic353003ad3de659d3a6b4e9d97295b42510f3bf7
Reviewed-on: https://go-review.googlesource.com/70431
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 02:35:56 +00:00
Frank Somers
c14dcfda6b runtime: factor amd64 specifics from vdso_linux.go
This is a preparation step for adding vDSO support on linux/386.

This change relocates the elf64 and amd64 specifics from
vdso_linux.go to a new vdso_linux_amd64.go.

This should enable vdso_linux.go to be used for vDSO
support on linux architectures other than amd64.

- Relocate the elf64X structure definitions appropriate to amd64,
  and change their names to elfX so that the code in vdso_linux.go
  is ELFnn-agnostic.

- Relocate the sym_keys and corresponding __vdso_* variables
  appropriate to amd64.

- Provide an amd64-specific constant for the maximum byte size of
  an array, and use this in vdso_linux.go to compute constants for
  sizing the elf structure arrays traversed in the loaded vDSO.

Change-Id: I1edb4e4ec9f2d79b7533aa95fbd09f771fa4edef
Reviewed-on: https://go-review.googlesource.com/69391
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 02:04:20 +00:00
David Crawshaw
c58b98b2d6 cmd/link, runtime: put hasmain bit in moduledata
Currently we look to see if the main.main symbol address is in the
module data text range. This requires access to the main.main
symbol, which usually the runtime has, but does not when building
a plugin.

To avoid a dynamic relocation to main.main (which I haven't worked
out how to have the linker generate on darwin), stop using the
symbol. Instead record a boolean in the moduledata if the module
has the main function.

Fixes #22175

Change-Id: If313a118f17ab499d0a760bbc2519771ed654530
Reviewed-on: https://go-review.googlesource.com/69370
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-13 01:13:33 +00:00
David Crawshaw
d06815ba3f cmd/link: split PE loader into its own package
For #22095

Change-Id: I8f48fce571b69a7e8edf2ad7733ffdfd38676e63
Reviewed-on: https://go-review.googlesource.com/70310
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 21:35:43 +00:00
Matthew Dempsky
53bbddd527 cmd/compile: intrinsify runtime/internal/sys.Ctz{32,64} on ppc64
These functions are identical to math/bits.TrailingZeros{32,64}, which
are already intrinsified on ppc64.

Change-Id: If7ee57e7afe53154874f4b66bacdb6237806128a
Reviewed-on: https://go-review.googlesource.com/70350
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-10-12 20:01:16 +00:00
Austin Clements
97920373fa cmd/link: generate PC ranges for compilation unit DIEs
When we split separate packages into separate compilation units, we
lost PC range information because it was no longer contiguous. This
brings it back by constructing proper per-package PC range tables.

Change-Id: Id0ab5187e08ac5d13b3d3794977bfc857a56224f
Reviewed-on: https://go-review.googlesource.com/69974
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-12 18:56:26 +00:00
Austin Clements
d4dda76b5f cmd/link: one DWARF compilation unit per package
Currently, the linker generates one huge DWARF compilation unit for
the entire Go binary. This commit creates a separate compilation unit
and line table per Go package.

We temporarily lose compilation unit PC range information, since it's
now discontiguous, so harder to emit. We'll bring it back in the next
commit.

Beyond being "more traditional", this has various technical
advantages:

* It should speed up line table lookup, since that requires a
  sequential scan of the line table. With this change, a debugger can
  first locate the per-package line table and then scan only that line
  table.

* Once we emit compilation unit PC ranges again, this should also
  speed up various other debugger reverse PC lookups.

* It puts us in a good position to move more DWARF generation into the
  compiler, which could produce at least the CU header, per-function
  line table fragments, and per-function frame unwinding info that the
  linker could simply paste together.

* It will let us record a per-package compiler command-line flags
  (#22168).

Change-Id: Ibac642890984636b3ef1d4b37fe97f4453c2cc84
Reviewed-on: https://go-review.googlesource.com/69973
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-12 18:56:23 +00:00
Austin Clements
ce6e0b089f cmd/link: remove silly sym.R[:0] truncation
The DWARF code currently clears all section relocations every time it
creates a section. This is unnecessary and confusing, so don't do it.

This dates back to
https://codereview.appspot.com/7891044/diff/26001/src/cmd/ld/dwarf.c.
At the time, this was only done for one symbol and that symbol was
used solely for collecting relocations (which is why it made sense to
clear the relocations but not the actual data). Furthermore, DWARF
generation potentially required two passes, so it was important to
clear the state from the first pass. None of this is true now, but
this pattern had been cargo-culted all over the dwarf.go.

Change-Id: I87d4ff8ccd5c807796241559be46168ce3ccb49a
Reviewed-on: https://go-review.googlesource.com/70312
Run-TryBot: Austin Clements <austin@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-12 18:56:20 +00:00
Austin Clements
77c27c3102 cmd/link: eliminate .debug_aranges
The .debug_aranges section is an odd vestige of DWARF, since its
contents are easy and efficient for a debugger to reconstruct from the
attributes of the top-level compilation unit DIEs. Neither GCC nor
clang emit it by default these days. GDB and Delve ignore it entirely.
LLDB will use it if present, but is happy to construct the index from
the compilation unit attributes (and, indeed, a remarkable variety of
other ways if those aren't available either).

We're about to split up the compilation units by package, which means
they'll have discontiguous PC ranges, which is going to make
.debug_aranges harder to construct (and larger).

Rather than try to maintain this essentially unused code, let's
simplify things and remove it.

Change-Id: I8e0ccc033b583b5b8908cbb2c879b2f2d5f9a50b
Reviewed-on: https://go-review.googlesource.com/69972
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-12 18:56:18 +00:00
Heschi Kreinick
a0402b6bf8 cmd/link: suppress unnecessary DWARF relocs that confuse dsymutil
During Mach-O linking, dsymutil takes the DWARF from individual object
files and combines it into a debug archive. Because it's content-aware,
it doesn't need our help to do its job. Nonetheless, it does try to
honor relocations that are present in its input.

When dsymutil encounters a relocation, it uses the value of that
relocation as an index into the debug map to find its final location.
When it does that, it's assuming that the value is an address in the
object file. But DWARF references are section-relative. So when it
processes a relocation for a DWARF reference, it gets confused,
and if the value happens to match the address of a function or
data symbol, it will rewrite it incorrectly.

Since the relocations don't help, and can hurt, drop them when
externally linking a Mach-O binary.

Fixes #22068

Change-Id: I8ec36da626575d9f6c8d0e7a0b76eab8ba22d62c
Reviewed-on: https://go-review.googlesource.com/68330
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-12 18:51:54 +00:00
Elias Naur
764a6ac29e runtime: don't restore the alternate signal stack on ios
The alternative signal stack doesn't work on ios, so the setup of
the alternative stack was skipped. The corresponding unminitSignals
was effectively a no-op on ios until CL 70130. Skip unminitSignals
on ios to restore the previous behaviour.

For the ios builders.

Change-Id: I5692ca7f5997e6b9d10cc5f2383a5a37c42b133c
Reviewed-on: https://go-review.googlesource.com/70270
Run-TryBot: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-12 16:59:32 +00:00
Russ Cox
6054f87f3a cmd/go: delete p.Internal.Target in favor of p.Target
The two are not meaningfully different, and it is confusing to have two.

Change-Id: Ie6a355ea4d79fb4bb79bf5124071a866038b19ba
Reviewed-on: https://go-review.googlesource.com/70211
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-12 13:56:15 +00:00
Alex Brainman
862fb86c6e internal/poll: only call SetFileCompletionNotificationModes for sockets
CL 36799 made SetFileCompletionNotificationModes to be called for
file handles. I don't think it is correct. Revert that change.

Fixes #22024
Fixes #22207

Change-Id: I26260e8a727131cffbf60958d79eca2457495554
Reviewed-on: https://go-review.googlesource.com/69871
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 07:13:23 +00:00
Alex Brainman
c37647fc3a internal/poll: do not call SetFileCompletionNotificationModes if it is broken
Current code assumes that SetFileCompletionNotificationModes
is safe to call even if we know that it is not safe to use
FILE_SKIP_COMPLETION_PORT_ON_SUCCESS flag. It appears (see issue #22149),
SetFileCompletionNotificationModes crashes when we call it without
FILE_SKIP_COMPLETION_PORT_ON_SUCCESS flag.

Do not call SetFileCompletionNotificationModes in that situation.
We are allowed to do that, because SetFileCompletionNotificationModes
is just an optimisation.

Fixes #22149

Change-Id: I0ad3aff4eabd8c27739417a62c286b1819ae166a
Reviewed-on: https://go-review.googlesource.com/69870
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 07:12:36 +00:00
Artyom Pervukhin
9ce43ce667 image/gif: make Decode only keep the first frame in memory
Decode decodes entire GIF image and returns the first frame as an
image.Image. There's no need for it to keep every decoded frame in
memory except for the one it returns.

Fixes #22199

Change-Id: I76b4bd31608ebc76a1a3df02e85c20eb80df7877
Reviewed-on: https://go-review.googlesource.com/69890
Reviewed-by: Nigel Tao <nigeltao@golang.org>
2017-10-12 05:44:11 +00:00
Austin Clements
58c7b1d160 runtime: fix dragonfly/amd64
CL 69292 unified the amd64 entry-points, but Dragonfly doesn't follow
the same entry-point argument conventions as most other amd64
platforms. Fix the Dragonfly entry point.

Change-Id: I0f84e2e4101ce68217af185ee9baaf455b8b6dad
Reviewed-on: https://go-review.googlesource.com/70212
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-12 04:03:50 +00:00
David du Colombier
926373ea79 runtime: fix crash on Plan 9
Since CL 46037, the runtime is crashing after calling
exitThread on Plan 9.

The exitThread function shouldn't be called on
Plan 9, because the system manages thread stacks.

Fixes #22221.

Change-Id: I5d61c9660a87dc27e4cfcb3ca3ddcb4b752f2397
Reviewed-on: https://go-review.googlesource.com/70190
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-12 00:11:33 +00:00
Matthew Dempsky
a509cae90d cmd/compile: record InlCost in export data
Previously, we were treating cross-package function calls as free for
inlining budgeting.

In theory, we should be able to recompute InlCost from the
exported/reimported function bodies. However, that process mutates the
structure of the Node AST enough that it doesn't preserve InlCost. To
avoid unexpected issues, just record and restore InlCost in the export
data.

Fixes #19261.

Change-Id: Iac2bc0d32d4f948b64524aca657051f9fc96d92d
Reviewed-on: https://go-review.googlesource.com/70151
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-11 23:20:44 +00:00
Daniel Martí
1fbeccb15a cmd/compile: deduplicate a few lines in swt.go
Noticed while reading some code that the two branches in this loop body
shared the last statements. Rewrite it in a way that they are not
duplicated.

Passes toolstash -cmp on std.

Change-Id: I3356ca9fa37c32eee496e221d7830bfc581dade1
Reviewed-on: https://go-review.googlesource.com/66470
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 23:03:47 +00:00
Hugues Bruant
4f70a2a699 cmd/compile: inline calls to local closures
Calls to a closure held in a local, non-escaping,
variable can be inlined, provided the closure body
can be inlined and the variable is never written to.

The current implementation has the following limitations:

 - closures with captured variables are not inlined because
   doing so naively triggers invariant violation in the SSA
   phase
 - re-assignment check is currently approximated by checking
   the Addrtaken property of the variable which should be safe
   but may miss optimization opportunities if the address is
   not used for a write before the invocation

Updates #15561

Change-Id: I508cad5d28f027bd7e933b1f793c14dcfef8b5a1
Reviewed-on: https://go-review.googlesource.com/65071
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 22:32:36 +00:00
Austin Clements
44d9e96da9 runtime: don't try to free OS-created signal stacks
Android's libc creates a signal stack for every thread it creates. In
Go, minitSignalStack picks up this existing signal stack and puts it
in m.gsignal.stack. However, if we later try to exit a thread (because
a locked goroutine is exiting), we'll attempt to stackfree this
libc-allocated signal stack and panic.

Fix this by clearing gsignal.stack when we unminitSignals in such a
situation.

This should fix the Android build, which is currently broken.

Change-Id: Ieea8d72ef063d22741c54c9daddd8bb84926a488
Reviewed-on: https://go-review.googlesource.com/70130
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 22:17:30 +00:00
Joe Tsai
a3e013b082 encoding/json: use Deprecated markers
In #10909, it was decided that "Deprecated:" is a magic string for
tools (e.g., #17056 for godoc) to detect deprecated identifiers.
Use those convention instead of custom written prose.

Change-Id: Ia514fc3c88fc502e86c6e3de361c435f4cb80b22
Reviewed-on: https://go-review.googlesource.com/70110
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
2017-10-11 22:09:22 +00:00
David Chase
edcf2d0cd6 cmd/compile: add line numbers to values & blocks in ssa.html
In order to improve the line numbering for debuggers,
it's necessary to trace lines through compilation.
This makes it (much) easier to follow.

The format of the last column of the ssa.html output was
also changed to reduce the spamminess of the file name,
which is usually the same and makes it far harder to read
instructions and line numbers, and to make it wider and also
able to break words when wrapping (long path names still
can push off the end otherwise; side-to-side scrolling was
tried but was more annoying than the occasional wrapped
line).

Sample output now, where [...] is elision for sake of making
the CL character-counter happy -- and the (##) line numbers
are rendered in italics and a smaller font (11 point) under
control of a CSS class "line-number".

genssa
      # /Users/drchase/[...]/ssa/testdata/hist.go
      00000 (35) TEXT	"".main(SB)
      00001 (35) FUNCDATA	$0, gclocals·7be4bb[...]1e8b(SB)
      00002 (35) FUNCDATA	$1, gclocals·9ab98a[...]4568(SB)
v920  00003 (36) LEAQ	""..autotmp_31-640(SP), DI
v858  00004 (36) XORPS	X0, X0
v6    00005 (36) LEAQ	-48(DI), DI
v6    00006 (36) DUFFZERO	$277
v576  00007 (36) LEAQ	""..autotmp_31-640(SP), AX
v10   00008 (36) TESTB	AX, (AX)
b1    00009 (36) JMP	10

and from an earlier phase:

b18: ← b17
v242 (47) = Copy <mem> v238
v243 (47) = VarKill <mem> {.autotmp_16} v242
v244 (48) = Addr <**bufio.Scanner> {scanner} v2
v245 (48) = Load <*bufio.Scanner> v244 v243
[...]
v279 (49) = Store <mem> {int64} v277 v276 v278
v280 (49) = Addr <*error> {.autotmp_18} v2
v281 (49) = Load <error> v280 v279
v282 (49) = Addr <*error> {err} v2
v283 (49) = VarDef <mem> {err} v279
v284 (49) = Store <mem> {error} v282 v281 v283
v285 (47) = VarKill <mem> {.autotmp_18} v284
v286 (47) = VarKill <mem> {.autotmp_17} v285
v287 (50) = Addr <*error> {err} v2
v288 (50) = Load <error> v287 v286
v289 (50) = NeqInter <bool> v288 v51
If v289 → b21 b22 (line 50)

Change-Id: I3f46310918f965761f59e6f03ea53067237c28a8
Reviewed-on: https://go-review.googlesource.com/69591
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-10-11 21:46:20 +00:00
Ian Lance Taylor
30cb30e596 runtime: unify amd64 -buildmode=c-archive/c-shared entry point code
This adds the _lib entry point to various GOOS_amd64.s files.
A future CL will enable c-archive/c-shared mode for those targets.

As far as I can tell, the newosproc0 function in os_darwin.go was
passing the wrong arguments to bsdthread_create. The newosproc0
function is never called in the current testsuite.

Change-Id: Ie7c1c2e326cec87013e0fea84f751091b0ea7f51
Reviewed-on: https://go-review.googlesource.com/69711
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-11 21:12:51 +00:00
David Crawshaw
ecfa7375e4 cmd/link: move ELF reader to its own package
Along the way, switch to using relocation constants from debug/elf.

For #22095

Change-Id: I1a64353619f95dde5aa39060c4b9d001af7dc1e4
Reviewed-on: https://go-review.googlesource.com/69013
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 20:53:39 +00:00
Russ Cox
d19ced040a cmd/dist: refresh deps.go after recent package io changes
Change-Id: Iaa960c85011289e047c64b53cf610838eb50332d
Reviewed-on: https://go-review.googlesource.com/70073
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-10-11 20:31:38 +00:00
Ian Lance Taylor
cf3f771203 runtime: unify amd64 -buildmode=exe entry point code
All of the amd64 entry point code is the same except for Plan 9.
Unify it all into asm_amd64.s.

Change-Id: Id47ce3a7bb2bb0fd48f326a2d88ed18b17dee456
Reviewed-on: https://go-review.googlesource.com/69292
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 20:07:31 +00:00
Austin Clements
e29efbcbcb cmd/link: fix some unintentional symbol creation
There are two places in DWARF generation that create symbols when they
really just want to get the symbol if it exists. writeranges, in
particular, will create a DWARF range symbol for every single textp
symbol (though they won't get linked into any list, so they don't
affect the binary).

Fix these to use ROLookup instead of Lookup.

Change-Id: I401eadf22890e296bd08bccaa6ba2fd8fac800cd
Reviewed-on: https://go-review.googlesource.com/69971
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-11 20:06:41 +00:00
Joe Tsai
371eda4558 io: simplify pipe implementation
In the distant past, Pipe was implemented with channels and a
long running pipe.run goroutine (see CL 994043).
This approach of having all communication serialized through the
run method was error prone giving Pipe a history of deadlocks
and race conditions.

After the introduction of sync.Cond, the implementation was rewritten
(see CL 4252057) to use condition variables and avoid the
long running pipe.run goroutine. While this implementation is superior
to the previous one, this implementation is strange in that the
p.data field is always set immediately prior to signaling the other
goroutine with Cond.Signal, effectively making the combination of the
two a channel-like operation. Inferior to a channel, however, this still
requires explicit locking around the p.data field.

The data+rwait can be effectively be replaced by a "chan []byte" to
inform a reader that there is data available.
The data+wwait can be effectively be replaced by a "chan int" to
inform a writer of how many bytes were read.

This implementation is a simplified from net.Pipe in CL 37402.

Change-Id: Ia5b26320b0525934fd87a3b69a091c787167f5aa
Reviewed-on: https://go-review.googlesource.com/65330
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
2017-10-11 20:00:54 +00:00
Joe Tsai
e2dd8ca946 net: implement deadline functionality on Pipe
Implement deadline functionality on Pipe so that it properly implements
the semantics of the Conn interface. This aids usages of Pipe (often in
unit tests) with a more realistic and complete implementation.

The new implementation avoids a dependency on a io.Pipe since it is
impossible to keep the prior semantics of synchronous reads and writes
while also trying to implement cancelation over an io.{Reader,Writer}
that fundamentally has no cancelation support.

The fact that net.Pipe is synchronous (and documented as such)
is unfortunate because no realistic network connection is synchronous.
Instead real networks introduces a read and write buffer of some sort.
However, we do not change the semantics for backwards compatibility.

The approach taken does not leave any long-running goroutines,
meaning that tests that never call Close will not cause a resource leak.

Fixes #18170

Change-Id: I5140b1f289a0a49fb2d485f031b5aa0ee99ecc30
Reviewed-on: https://go-review.googlesource.com/37402
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 20:00:52 +00:00
Russ Cox
7dcd33302a cmd/internal/buildid: add missing f.Close in ReadFile
On Windows, not closing f keeps us from being able to remove it.

Change-Id: Id4cb709b6ce0b30485b87364a9f0e6e71d2782bd
Reviewed-on: https://go-review.googlesource.com/70070
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 19:38:04 +00:00
Russ Cox
31896332b3 cmd/dist: reenable TestDeps
It looks like I forgot to reenable this test when I fixed #21522.
Update deps.go and reenable.

Change-Id: I68a45df09b418f48d93d2e7ab1d274e056c192e6
Reviewed-on: https://go-review.googlesource.com/70050
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 19:10:31 +00:00
Russ Cox
cdbc363cb2 cmd/go: record both build ID and content ID in archives and binaries
The content ID will be needed for content-based staleness
determination. It is defined as the SHA256 hash of the file
in which it appears, with occurrences of the build+content IDs
changed to zeros during the hashing operation.

Storing the content ID in the archives is a little tricky
but it means that later builds need not rehash the archives
each time they are referenced, so under the assumption
that each package is imported at least once after being
compiled, hashing at build time is a win. (Also the whole
file is more likely to be in cache at build time,
since we just wrote it.)

In my unscientific tests, the time for "go build -a std cmd"
rises from about 14.3s to 14.5s on my laptop, or under 2%.

Change-Id: Ia3d4dc657d003e8295631f73363868bd92ebf96a
Reviewed-on: https://go-review.googlesource.com/69054
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 19:03:26 +00:00
Austin Clements
85f93c889a cmd/compile: fix some plive comments
The liveness analysis no longer directly emits PCDATA. Fix stale
comments that say so.

Change-Id: Id26b112ddf4c13a12ebf766f64bf57c68fbfe3ef
Reviewed-on: https://go-review.googlesource.com/67691
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 18:29:36 +00:00
Keith Randall
e130dcf051 cmd/compile: abort earlier if stack frame too large
If the stack frame is too large, abort immediately.
We used to generate code first, then abort.
In issue 22200, generating code raised a panic
so we got an ICE instead of an error message.

Change the max frame size to 1GB (from 2GB).
Stack frames between 1.1GB and 2GB didn't used to work anyway,
the pcln table generation would have failed and generated an ICE.

Fixes #22200

Change-Id: I1d918ab27ba6ebf5c87ec65d1bccf973f8c8541e
Reviewed-on: https://go-review.googlesource.com/69810
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 18:24:13 +00:00
Keith Randall
624630b824 cmd/compile: fold constant comparisions into SETxxmem ops.
Fixes #22198

Change-Id: I5cb91c73069af8b16a2580d28756efd58c84b690
Reviewed-on: https://go-review.googlesource.com/69990
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 18:23:09 +00:00
Russ Cox
9ad2319bbc cmd/buildid: add new tool factoring out code needed by go command
This CL does a few things.

1. It moves the existing "read a build ID" code out of the go command
and into cmd/internal/buildid.

2. It adds new code there to "write a build ID".

3. It adds better tests.

4. It encapsulates cmd/internal/buildid into a new standalone program
"go tool buildid".

The go command is going to use the new "write a build ID" functionality
in a future CL. Adding the separate "go tool buildid" gives "go build -x"
a printable command to explain what it is doing in that new step.
(This is similar to the go command printing "go tool pack" commands
equivalent to the actions it is taking, even though it's not invoking pack
directly.) Keeping go build -x honest means that other build systems can
potentially keep up with the go command.

Change-Id: I01c0a66e30a80fa7254e3f2879283d3cd7aa03b4
Reviewed-on: https://go-review.googlesource.com/69053
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 18:16:02 +00:00
Austin Clements
0bede7f34e cmd/compile: split TestNexting into subtests
This makes it more obvious which of the two builds is failing by
putting "dbg" or "opt" directly in the test name. It also makes it
possible for them to fail independently, so a failure in "dbg" doesn't
mask a failure in "opt", and to visibly skip the opt test when run
with an unoptimized runtime.

Change-Id: I3403a7fd3c1a13ad51a938bb95dfe54c320bb58e
Reviewed-on: https://go-review.googlesource.com/69970
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
2017-10-11 17:53:10 +00:00
Austin Clements
0aef82aa4a runtime: make (Un)LockOSThread doc more prescriptive
Right now users have to infer why they would want LockOSThread and
when it may or may not be appropriate to call UnlockOSThread. This
requires some understanding of Go's internal thread pool
implementation, which is unfortunate.

Improve the situation by making the documentation on these functions
more prescriptive so users can figure out when to use them even if
they don't know about the scheduler.

Change-Id: Ide221791e37cb5106dd8a172f89fbc5b3b98fe32
Reviewed-on: https://go-review.googlesource.com/52871
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:23 +00:00
Austin Clements
4f34a52913 runtime: terminate locked OS thread if its goroutine exits
runtime.LockOSThread is sometimes used when the caller intends to put
the OS thread into an unusual state. In this case, we never want to
return this thread to the runtime thread pool. However, currently
exiting the goroutine implicitly unlocks its OS thread.

Fix this by terminating the locked OS thread when its goroutine exits,
rather than simply returning it to the pool.

Fixes #20395.

Change-Id: I3dcec63b200957709965f7240dc216fa84b62ad9
Reviewed-on: https://go-review.googlesource.com/46038
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:21 +00:00
Austin Clements
eff2b2620d runtime: make it possible to exit Go-created threads
Currently, threads created by the runtime exist until the whole
program exits. For #14592 and #20395, we want to be able to exit and
clean up threads created by the runtime. This commit implements that
mechanism.

The main difficulty is how to clean up the g0 stack. In cgo mode and
on Solaris and Windows where the OS manages thread stacks, we simply
arrange to return from mstart and let the system clean up the thread.
If the runtime allocated the g0 stack, then we use a new exitThread
syscall wrapper that arranges to clear a flag in the M once the stack
can safely be reaped and call the thread termination syscall.

exitThread is based on the existing exit1 wrapper, which was always
meant to terminate the calling thread. However, exit1 has never been
used since it was introduced 9 years ago, so it was broken on several
platforms. exitThread also has the additional complication of having
to flag that the stack is unused, which requires some tricks on
platforms that use the stack for syscalls.

This still leaves the problem of how to reap the unused g0 stacks. For
this, we move the M from allm to a new freem list as part of the M
exiting. Later, allocm scans the freem list, finds Ms that are marked
as done with their stack, removes these from the list and frees their
g0 stacks. This also allows these Ms to be garbage collected.

This CL does not yet use any of this functionality. Follow-up CLs
will. Likewise, there are no new tests in this CL because we'll need
follow-up functionality to test it.

Change-Id: Ic851ee74227b6d39c6fc1219fc71b45d3004bc63
Reviewed-on: https://go-review.googlesource.com/46037
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:18 +00:00
Russ Cox
a9c3d09d0e cmd/go: make cmd/* default to go tool installation
Every cmd/thing is 'go tool thing' except for go and gofmt.
But the table in cmd/go enumerates all the things instead of
saying that go and gofmt are the exceptions.
Change that, so that when adding new tools it's not
necessary to update this table.

Change-Id: Ia6fef41b4d967249b19971a0d03e5acb0317ea82
Reviewed-on: https://go-review.googlesource.com/69052
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 17:47:17 +00:00
Austin Clements
6c7bea6309 runtime: replace sched.mcount int32 with sched.mnext int64
Currently, since Ms never exit, the number of Ms, the number of Ms
ever created, and the ID of the next M are all the same and must be
small. That's about to change, so rename sched.mcount to sched.mnext
to make it clear it's the number of Ms ever created (and the ID of the
next M), change its type to int64, and use mcount() for the number of
Ms. In the next commit, mcount() will become slightly less trivial.

For #20395.

Change-Id: I9af34d36bd72416b5656555d16e8085076f1b196
Reviewed-on: https://go-review.googlesource.com/68750
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:16 +00:00
Russ Cox
d7ac5ce8a3 cmd/go: hoist C++, Objective-C, and Fortran checks earlier
Today they happen during the build phase; they should happen
during the load phase instead, along with the C check.

Change-Id: I6074a995b8e29275549aafa574511b735642d85b
Reviewed-on: https://go-review.googlesource.com/69051
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 17:47:14 +00:00
Austin Clements
a212083eea runtime: mark mstart as nowritebarrierrec
mstart is the entry point for new threads, so it certainly can't
interact with GC enough to have write barriers. We move the one small
piece that is allowed to have write barriers out into its own
function.

Change-Id: Id9c31d6ffac31d0051fab7db15eb428c11cadbad
Reviewed-on: https://go-review.googlesource.com/46035
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-10-11 17:47:13 +00:00
Russ Cox
8f7f46f5a6 cmd/go: replace a.Package.Internal.Pkgfile with a.built
Logically the build needs to start treating a.Package as immutable,
since we might want to build a.Package multiple ways.
Record the built target in a.built instead.

Right now a.built is predictable ahead of time, but we want to
move toward satisfying some builds from a cache directory,
in which case a.built will point into the cache directory
and not be determined until action execution time.

There is probably more to do with shared libraries, but this
does not break what's there.

Change-Id: I941988b520bee2f664fd8cabccf389e1dc29628b
Reviewed-on: https://go-review.googlesource.com/69050
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 17:47:12 +00:00
Austin Clements
12ec54724b runtime: make m.nextwaitm an muintptr
This field is really a *m (modulo its bottom bit). Change it from
uintptr to muintptr to document this fact.

Change-Id: I2d181a955ef1d2c1a268edf20091b440d85726c9
Reviewed-on: https://go-review.googlesource.com/46034
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2017-10-11 17:47:10 +00:00
Russ Cox
4e8be99590 cmd/go: clean up compile vs link vs shared library actions
Everything got a bit tangled together in b.action1.
Try to tease things apart again.

In general this is a refactoring of the existing code, with limited
changes to the effect of the code.

The main additional change is to complete a.Deps for link actions.
That list now directly contains all the inputs the linker will attempt
to read, eliminating the need for a transitive traversal of the entire
action graph to find those. The comepleteness of a.Deps will be
important when we eventually use it to decide whether an cached
action output can be reused.

all.bash passes, but it's possible I've broken some subtety of
buildmode=shared again. Certainly that code took the longest
to get working.

Change-Id: I34e849eda446dca45a9cfce02b07bec6edb6d0d4
Reviewed-on: https://go-review.googlesource.com/69831
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 17:47:09 +00:00
Austin Clements
2595fe7fb6 runtime: don't start new threads from locked threads
Applications that need to manipulate kernel thread state are currently
on thin ice in Go: they can use LockOSThread to prevent other
goroutines from running on the manipulated thread, but Go may clone
this manipulated state into a new thread that's put into the runtime's
thread pool along with other threads.

Fix this by never starting a new thread from a locked thread or a
thread that may have been started by C. Instead, the runtime starts a
"template thread" with a known-good state. If it then needs to start a
new thread but doesn't know that the current thread is in a good
state, it forwards the thread creation to the template thread.

Fixes #20676.

Change-Id: I798137a56e04b7723d55997e9c5c085d1d910643
Reviewed-on: https://go-review.googlesource.com/46033
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 17:47:08 +00:00
Russ Cox
9a9780a20d cmd/go: separate compile and link steps in action graph
To the extent that invoking the compiler and invoking the linker
have different dependency requirements, representing both steps
by a single action node leads to confusion.

If we move to having separate .a and .x (import metadata) files
in the standard builds, then the .a is a link dependency but not
a compile dependency, and vice versa for .x.
Today, in shared library builds, the .a is a compile dependency
and a link dependency, while the .so is only a link dependency.

Also in this CL: change the gccgo link step to extract _cgo_flags
into root.Objdir, which is private to the link step, instead of into
b.WorkDir, which is shared by all the link steps that could possibly
be running in parallel. And attempt to handle the -n and -x flags
when loading _cgo_flags, instead of dying attempting to read
an archive that wasn't written.

Also in this CL: create a.Objdir before running a.Func, to avoid
duplicating the Mkdir(a.Objdir) in every a.Func.

A future CL will update the link action's Deps to be accurate.
(Right now the link steps search out the true Deps by walking
the entire action graph.)

Change-Id: I15128ce2bd064887f98abc3a4cf204241f518631
Reviewed-on: https://go-review.googlesource.com/69830
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-11 17:47:06 +00:00
David Crawshaw
0c6fc0d711 debug/elf: add relocation constants
Compiled from various tables found around the internet.

Some of these are used by cmd/link.

Change-Id: I258b25e694dbe91a61d675763f2c47ccc928fd70
Reviewed-on: https://go-review.googlesource.com/69012
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 16:40:10 +00:00
Ian Lance Taylor
862b78e155 cmd/go: correct directory used in checkNestedVCS test
This error was not used when using git because nested git is permitted.
Add test using Mercurial, so that at least we have a test, even though
the test is not run by default.

Fixes #22157
Fixes #22201

Change-Id: If521f3c09b0754e00e56fa3cd0364764a57a43ad
Reviewed-on: https://go-review.googlesource.com/69670
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-10-11 14:45:43 +00:00
Ben Shi
1ec78d1dd1 cmd/compile: optimize ARM code with CMN/TST/TEQ
CMN/TST/TEQ were supported since ARMv4, which can be used to
simplify comparisons.

This patch implements the optimization and here are the benchmark
results.

1. A special test case got 18.21% improvement.
name                     old time/op    new time/op    delta
TSTTEQ-4                    806µs ± 1%     659µs ± 0%  -18.21%  (p=0.000 n=20+18)
(https://github.com/benshi001/ugo1/blob/master/tstteq_test.go)

2. There is no regression in the compilecmp benchmark.
name        old time/op       new time/op       delta
Template          2.31s ± 1%        2.30s ± 1%    ~     (p=0.661 n=10+9)
Unicode           1.32s ± 3%        1.32s ± 5%    ~     (p=0.280 n=10+10)
GoTypes           7.69s ± 1%        7.65s ± 0%  -0.52%  (p=0.027 n=10+8)
Compiler          36.5s ± 1%        36.4s ± 1%    ~     (p=0.546 n=9+9)
SSA               85.1s ± 2%        84.9s ± 1%    ~     (p=0.529 n=10+10)
Flate             1.43s ± 2%        1.43s ± 2%    ~     (p=0.661 n=10+9)
GoParser          1.81s ± 2%        1.81s ± 1%    ~     (p=0.796 n=10+10)
Reflect           5.10s ± 2%        5.09s ± 1%    ~     (p=0.853 n=10+10)
Tar               2.47s ± 1%        2.48s ± 1%    ~     (p=0.123 n=10+10)
XML               2.59s ± 1%        2.58s ± 1%    ~     (p=0.853 n=10+10)
[Geo mean]        4.78s             4.77s       -0.17%

name        old user-time/op  new user-time/op  delta
Template          2.72s ± 3%        2.73s ± 2%    ~     (p=0.928 n=10+10)
Unicode           1.58s ± 4%        1.60s ± 1%    ~     (p=0.087 n=10+9)
GoTypes           9.41s ± 2%        9.36s ± 1%    ~     (p=0.060 n=10+10)
Compiler          44.4s ± 2%        44.2s ± 2%    ~     (p=0.289 n=10+10)
SSA                110s ± 2%         110s ± 1%    ~     (p=0.739 n=10+10)
Flate             1.67s ± 2%        1.63s ± 3%    ~     (p=0.063 n=10+10)
GoParser          2.12s ± 1%        2.12s ± 2%    ~     (p=0.840 n=10+10)
Reflect           5.94s ± 1%        5.98s ± 1%    ~     (p=0.063 n=9+10)
Tar               3.01s ± 2%        3.02s ± 2%    ~     (p=0.584 n=10+10)
XML               3.04s ± 3%        3.02s ± 2%    ~     (p=0.696 n=10+10)
[Geo mean]        5.73s             5.72s       -0.20%

name        old text-bytes    new text-bytes    delta
HelloSize         579kB ± 0%        579kB ± 0%    ~     (all equal)

name        old data-bytes    new data-bytes    delta
HelloSize        5.46kB ± 0%       5.46kB ± 0%    ~     (all equal)

name        old bss-bytes     new bss-bytes     delta
HelloSize        72.8kB ± 0%       72.8kB ± 0%    ~     (all equal)

name        old exe-bytes     new exe-bytes     delta
HelloSize        1.03MB ± 0%       1.03MB ± 0%    ~     (all equal)

3. There is little change in the go1 benchmark (excluding the noise).
name                     old time/op    new time/op     delta
BinaryTree17-4              40.3s ± 1%      40.6s ± 1%  +0.80%  (p=0.000 n=30+30)
Fannkuch11-4                24.2s ± 1%      24.1s ± 0%    ~     (p=0.093 n=30+30)
FmtFprintfEmpty-4           834ns ± 0%      826ns ± 0%  -0.93%  (p=0.000 n=29+24)
FmtFprintfString-4         1.39µs ± 1%     1.36µs ± 0%  -2.02%  (p=0.000 n=30+30)
FmtFprintfInt-4            1.43µs ± 1%     1.44µs ± 1%    ~     (p=0.155 n=30+29)
FmtFprintfIntInt-4         2.09µs ± 0%     2.11µs ± 0%  +1.16%  (p=0.000 n=28+30)
FmtFprintfPrefixedInt-4    2.33µs ± 1%     2.36µs ± 0%  +1.25%  (p=0.000 n=30+30)
FmtFprintfFloat-4          4.27µs ± 1%     4.32µs ± 1%  +1.27%  (p=0.000 n=30+30)
FmtManyArgs-4              8.18µs ± 0%     8.14µs ± 0%  -0.46%  (p=0.000 n=25+27)
GobDecode-4                 101ms ± 1%      101ms ± 1%    ~     (p=0.182 n=29+29)
GobEncode-4                89.6ms ± 1%     87.8ms ± 2%  -2.02%  (p=0.000 n=30+29)
Gzip-4                      4.07s ± 1%      4.08s ± 1%    ~     (p=0.173 n=30+27)
Gunzip-4                    602ms ± 1%      600ms ± 1%  -0.29%  (p=0.000 n=29+28)
HTTPClientServer-4          679µs ± 4%      683µs ± 3%    ~     (p=0.197 n=30+30)
JSONEncode-4                241ms ± 1%      239ms ± 1%  -0.84%  (p=0.000 n=30+30)
JSONDecode-4                903ms ± 1%      882ms ± 1%  -2.33%  (p=0.000 n=30+30)
Mandelbrot200-4            41.8ms ± 0%     41.8ms ± 0%    ~     (p=0.719 n=30+30)
GoParse-4                  45.5ms ± 1%     45.8ms ± 1%  +0.52%  (p=0.000 n=30+30)
RegexpMatchEasy0_32-4      1.27µs ± 1%     1.27µs ± 0%  -0.60%  (p=0.000 n=30+30)
RegexpMatchEasy0_1K-4      7.77µs ± 6%     7.69µs ± 4%  -0.96%  (p=0.040 n=30+30)
RegexpMatchEasy1_32-4      1.29µs ± 1%     1.28µs ± 1%  -0.54%  (p=0.000 n=30+30)
RegexpMatchEasy1_1K-4      10.3µs ± 6%     10.2µs ± 3%    ~     (p=0.453 n=30+27)
RegexpMatchMedium_32-4     1.98µs ± 1%     2.00µs ± 1%  +0.85%  (p=0.000 n=30+29)
RegexpMatchMedium_1K-4      503µs ± 0%      503µs ± 1%    ~     (p=0.752 n=30+30)
RegexpMatchHard_32-4       27.1µs ± 1%     26.5µs ± 0%  -1.96%  (p=0.000 n=30+24)
RegexpMatchHard_1K-4        809µs ± 1%      799µs ± 1%  -1.29%  (p=0.000 n=29+30)
Revcomp-4                  67.3ms ± 2%     67.2ms ± 1%    ~     (p=0.265 n=29+29)
Template-4                  1.08s ± 1%      1.07s ± 0%  -1.39%  (p=0.000 n=30+22)
TimeParse-4                6.93µs ± 1%     6.96µs ± 1%  +0.40%  (p=0.005 n=30+30)
TimeFormat-4               13.3µs ± 0%     13.3µs ± 1%    ~     (p=0.734 n=30+30)
[Geo mean]                  709µs           707µs       -0.32%

name                     old speed      new speed       delta
GobDecode-4              7.59MB/s ± 1%   7.57MB/s ± 1%    ~     (p=0.145 n=29+29)
GobEncode-4              8.56MB/s ± 1%   8.74MB/s ± 1%  +2.07%  (p=0.000 n=30+29)
Gzip-4                   4.76MB/s ± 1%   4.75MB/s ± 1%  -0.25%  (p=0.037 n=30+30)
Gunzip-4                 32.2MB/s ± 1%   32.3MB/s ± 1%  +0.29%  (p=0.000 n=29+28)
JSONEncode-4             8.04MB/s ± 1%   8.11MB/s ± 1%  +0.85%  (p=0.000 n=30+30)
JSONDecode-4             2.15MB/s ± 1%   2.20MB/s ± 1%  +2.29%  (p=0.000 n=30+30)
GoParse-4                1.27MB/s ± 1%   1.26MB/s ± 1%  -0.73%  (p=0.000 n=30+30)
RegexpMatchEasy0_32-4    25.1MB/s ± 1%   25.3MB/s ± 0%  +0.61%  (p=0.000 n=30+30)
RegexpMatchEasy0_1K-4     131MB/s ± 6%    133MB/s ± 4%  +1.35%  (p=0.009 n=28+30)
RegexpMatchEasy1_32-4    24.9MB/s ± 1%   25.0MB/s ± 1%  +0.54%  (p=0.000 n=30+30)
RegexpMatchEasy1_1K-4    99.2MB/s ± 6%  100.2MB/s ± 3%    ~     (p=0.448 n=30+27)
RegexpMatchMedium_32-4    503kB/s ± 1%    500kB/s ± 0%  -0.66%  (p=0.002 n=30+24)
RegexpMatchMedium_1K-4   2.04MB/s ± 0%   2.04MB/s ± 1%    ~     (p=0.358 n=30+30)
RegexpMatchHard_32-4     1.18MB/s ± 1%   1.20MB/s ± 1%  +1.75%  (p=0.000 n=30+30)
RegexpMatchHard_1K-4     1.26MB/s ± 1%   1.28MB/s ± 1%  +1.42%  (p=0.000 n=30+30)
Revcomp-4                37.8MB/s ± 2%   37.8MB/s ± 1%    ~     (p=0.266 n=29+29)
Template-4               1.80MB/s ± 1%   1.82MB/s ± 1%  +1.46%  (p=0.000 n=30+30)
[Geo mean]               6.91MB/s        6.96MB/s       +0.70%

fixes #21583

Change-Id: I24065a80588ccae7de3ad732a3cfb0026cf7e214
Reviewed-on: https://go-review.googlesource.com/67490
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 14:03:00 +00:00
Frank Somers
4477107b7b runtime: move vdso_linux_amd64.go to vdso_linux.go
This is a preparation step for adding vDSO support on linux/386.

In a follow-on change, the vDSO ELF symbol lookup code in this
file will be refactored so it can be used on multiple architectures.

First, move the file to an architecture-neutral file name so that
the change history is preserved. Build tags are added so that the
build behaves as it did before.

vdso_linux_amd64.go will be recreated later, just containing the
amd64 specifics.

If the move and refactor were combined in a single change, then the
history to date would be lost because git would see the existing code
as a new file.

Change-Id: Iddb5da0d7faf141fd7cc835fe6a80c80153897e9
Reviewed-on: https://go-review.googlesource.com/69710
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 13:42:27 +00:00
Daniel Martí
6013052e7d cmd/compile: eliminate some lineno uses
Focused on ranges, selects and switches for this one.

While at it, simplify some vars in typecheckselect.

Updates #19683.

Change-Id: Ib6aabe0f6826cb1930483aeb4bb2de1ff8052d9e
Reviewed-on: https://go-review.googlesource.com/69690
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 09:20:20 +00:00
Alberto Donizetti
07f7db3ea9 cmd/compile: fix OTYPESW Op comment
OTYPESW Op comment says

  // List = Left.(type)

this seems to be wrong. Adding

  fmt.Printf("n: %v\n", cond)
  fmt.Printf("  n.List: %v\n", cond.List)
  fmt.Printf("  n.Left: %v\n", cond.Left)
  fmt.Printf("  n.Right: %v\n", cond.Right)

to (s *typeSwitch) walk(sw *Node), and compiling the following code
snippet

  var y interface{}
  switch x := y.(type) {
  default:
    println(x)
  }

prints

  n: <node TYPESW>
    n.List:
    n.Left: x
    n.Right: y

The correct OTYPESW Node field positions are

  // Left = Right.(type)

This is confirmed by the fact that, further in the code,
typeSwitch.walk() checks that Right (and not Left) is of type
interface:

  cond.Right = walkexpr(cond.Right, &sw.Ninit)
  if !cond.Right.Type.IsInterface() {
    yyerror("type switch must be on an interface")
    return
  }

This patch fixes the OTYPESW comment.

Change-Id: Ief1e409cfabb7640d7f7b0d4faabbcffaf605450
Reviewed-on: https://go-review.googlesource.com/69112
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 07:55:04 +00:00
Ian Lance Taylor
0c53b4ec4f cmd/compile: disable TestNexting in short mode
Updates #22206

Change-Id: If75feddc01f8f86f294929fa7081c70eb15e581d
Reviewed-on: https://go-review.googlesource.com/69790
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-10-11 03:11:50 +00:00
griesemer
68e390304e cmd/compile/internal/syntax: consider function nesting for error recovery
This re-enables functionality that inadvertently was disabled in the
(long) past.

Also, don't perform branch checks if we had errors in a function
to avoid spurious errors or (worst-case) crashes.

Slightly modified test/fixedbugs/issue14006.go to make sure the
test still reports invalid label errors (the surrounding function
must be syntactically correct).

Change-Id: Id5642930877d7cf3400649094ec75c753b5084b7
Reviewed-on: https://go-review.googlesource.com/69770
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 00:29:58 +00:00
griesemer
39edffb6b1 cmd/compile/internal/syntax: factor out parsing of func bodies (cleanup)
Change-Id: If6481a5401940a923fc9a104981dfb90eed0d1ac
Reviewed-on: https://go-review.googlesource.com/69750
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 00:29:46 +00:00
griesemer
c87fb208c5 cmd/compile/internal/syntax: remove some outdated comments (cleanup)
Change-Id: If242bb99d501420827b764c908580f2363e01ac4
Reviewed-on: https://go-review.googlesource.com/69730
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 00:29:33 +00:00
Carlos Eduardo Seo
3a165bba34 cmd/asm, cmd/internal/obj/ppc64: Fix Data Cache instructions for ppc64x
This change fixes the implementation of Data Cache instructions for
ppc64x, allowing non-zero hint field values.

Change-Id: I454aac9293d069a4817ee574d5809fa1799b3216
Reviewed-on: https://go-review.googlesource.com/68670
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
2017-10-10 21:25:33 +00:00
Joe Tsai
577aab0c59 archive/tar: ignore ChangeTime and AccessTime unless Format is specified
CL 59230 changed Writer.WriteHeader to ignore the ChangeTime and AccessTime
fields when considering using the USTAR format when the format is unspecified.
This policy is confusing and leads to unexpected behavior where some files
have ModTime only, while others have ModTime+AccessTime+ChangeTime if the
format became PAX for some unrelated reason (e.g., long pathname).

Change the policy to simply always ignore ChangeTime, AccessTime, and
sub-second time resolutions unless the user explicitly specifies a format.
This is a safe policy change since WriteHeader had no support for the
above features in any Go release.

Support for ChangeTime and AccessTime was added in CL 55570.
Support for sub-second times was added in CL 55552.
Both CLs landed after the latest Go release (i.e., Go1.9), which was
cut from the master branch around August 6th, 2017.

Change-Id: Ib82baa1bf9dd4573ed4f674b7d55d15f733a4843
Reviewed-on: https://go-review.googlesource.com/69296
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-10 20:13:27 +00:00
Joe Tsai
4cd58c2f26 archive/tar: improve handling of directory paths
The USTAR format says:
<<<
Implementors should be aware that the previous file format did not include
a mechanism to archive directory type files.
For this reason, the convention of using a filename ending with
<slash> was adopted to specify a directory on the archive.
>>>

In light of this suggestion, make the following changes:
* Writer.WriteHeader refuses to encode a header where a file that
is obviously a file-type has a trailing slash in the name.
* formatter.formatString avoids encoding a trailing slash in the event
that the string is truncated (the full string will be encoded elsewhere,
so stripping the slash is safe).
* Reader.Next treats a TypeRegA (which is the zero value of Typeflag)
as a TypeDir if the name has a trailing slash.

Change-Id: Ibf27aa8234cce2032d92e5e5b28546c2f2ae5ef6
Reviewed-on: https://go-review.googlesource.com/69293
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-10 20:11:26 +00:00
Cherry Zhang
d63de28711 cmd/compile: intrinsify atomics on MIPS64
Change-Id: Ica65b7a52af9558a05d0a0e1dff0f9ec838f4117
Reviewed-on: https://go-review.googlesource.com/68830
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-10 19:43:38 +00:00
Matthew Dempsky
b80029ccf4 cmd/compile: simplify mkinlcall1
mkinlcall1 already guards against recursively inlining functions into
themselves, so there's no need to clear and restore fn.Func.Inl during
recursive inlining.

Passes toolstash-check.

Change-Id: I8bf0c8dea8788d94d3ea5670610b4acb1d26d2fb
Reviewed-on: https://go-review.googlesource.com/69310
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-10 17:53:27 +00:00
Matthew Dempsky
f58c6c9915 cmd/compile: remove outdated TODO about inlining
We've supported inlining methods called as functions for a while now.

Change-Id: I53fba426e45f91d65a38f00456c2ae1527372b50
Reviewed-on: https://go-review.googlesource.com/69530
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-10 17:53:22 +00:00
Russ Cox
3a8b9cfe91 testing: add PAUSE, CONT output lines to explain Parallel execution
This should make parallel execution a bit clearer.
With -p=1 it should make the execution completely unambiguous.

Fixes #19280.

Change-Id: Ib48cdfe96896d01b0d8f98ccb2fab614407a7d92
Reviewed-on: https://go-review.googlesource.com/49430
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-10 17:44:22 +00:00
Daniel Martí
f14f7b3141 cmd/compile: make bad Ctypes be only 0
Before, -1 meant a node being nil or not an OLITERAL, and 0 meant an
OLITERAL missing a Val.

However, the use of this value was confusing and led to some issues,
such as swt.go checking for < 0 instead of <= 0, causing panics.

We never need to differentiate these two cases, so collapse both into 0.
To make it clear that negative values can no longer happen, make Ctype
an uint8.

With this change, we can now get rid of the two n.Type == nil checks
in swt.go added to fix a couple of these panics.

Thanks to Matthew Dempsky for spotting this inconsistency.

Fixes #22001.

Change-Id: I51c65a76f38a3e16788b6a3b57932dad3436dc7e
Reviewed-on: https://go-review.googlesource.com/69510
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-10 17:06:53 +00:00
Cherry Zhang
d5a2925b7d cmd/compile: clean up ADDconst on PPC64
ADDconst op is no longer used for addresses, as we lower Addr to
MOVDaddr. There is no rule that produces ADDconst with a non-nil
sym. So we can remove the sym aux field in ADDconst and limit its
use for adding constant (not offset to symbol).

Passes "toolstash -cmp" on std cmd for GOARCH=ppc64 and ppc64le.

Change-Id: Icee35cdb34d8d121ad7035076dfd07595c7ff809
Reviewed-on: https://go-review.googlesource.com/69450
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
2017-10-10 15:54:13 +00:00