Adding the Go Time podcast under the `Stay informed` section of the help
page on the website.
Change-Id: Ifb1c6bb20cbf640a91572d47f14a432f58439261
Reviewed-on: https://go-review.googlesource.com/41146
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
At VARKILLs, zero a variable if it is ambiguously live.
After the VARKILL anything this variable references
might be collected. If it were to become live again later,
the GC will see references to already-collected objects.
We don't know a variable is ambiguously live until very
late in compilation (after lowering, register allocation, ...),
so it is hard to generate the code in an arch-independent way.
We also have to be careful not to clobber any registers.
Fortunately, this almost never happens so performance is ~irrelevant.
There are only 2 instances where this triggers in the stdlib.
Fixes#20029
Change-Id: Ia9585a91d7b823fad4a9d141d954464cc7af31f4
Reviewed-on: https://go-review.googlesource.com/41076
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Make poolLocal size multiple of 128, so it aligns to CPU cache line
on the most common architectures.
This also has the following benefits:
- It may help compiler substituting integer multiplication
by bit shift inside indexLocal.
- It shrinks poolLocal size from 176 bytes to 128 bytes on amd64,
so now it fits two cache lines (or a single cache line on certain
Intel CPUs - see https://software.intel.com/en-us/articles/optimizing-application-performance-on-intel-coret-microarchitecture-using-hardware-implemented-prefetchers).
No measurable performance changes on linux/amd64 and linux/386.
Change-Id: I11df0f064718a662e77a85d88b8a15a8919f25e9
Reviewed-on: https://go-review.googlesource.com/40918
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
There were only two versions, 0 and 1,
and the only user of version 1 was the assembler,
to indicate that a symbol was static.
Rename LSym.Version to Static,
and add it to LSym.Attributes.
Simplify call-sites.
Passes toolstash-check.
Change-Id: Iabd39918f5019cce78f381d13f0481ae09f3871f
Reviewed-on: https://go-review.googlesource.com/41201
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Imported interfaces must be completed, whether they are named or not.
The original code was collecting all types (including anonymous ones)
in the importer's typList. That list was used in the end to complete
interface types. When we introduced tracking of named types only, we
lost anonymous interfaces. Use an independent list of interface types
so the completion code is independent of which types are tracked.
Added test and factored some of the existing tests.
Fixes#20046.
Change-Id: Icd1329032aec33f96890380dd5042de3bef8cdc7
Reviewed-on: https://go-review.googlesource.com/41198
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TestBreakpoint expects to see "runtime.Breakpoint()" in the stack trace.
If runtime.Breakpoint() is inlined, then the stack trace prints
"runtime.Breakpoint(...)" since the runtime does not have information
about arguments (or lack thereof) to inlined functions. This change
makes the test independent of inlining by looking for the string
"runtime.Breakpoint(". Now TestBreakpoint passes with -l=4.
Change-Id: Ia044a8e8a4de2337cb2b393d6fa78c73a2f25926
Reviewed-on: https://go-review.googlesource.com/40997
Run-TryBot: David Lazar <lazard@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TestBlockProfile matches samples against a regexp that accepts "," in
profile PCs. I suspect this was just a syntax mistake. Remove "," from
the character class.
Change-Id: Idcfc20ed6900075abae08597ba71db559e89b37b
Reviewed-on: https://go-review.googlesource.com/41111
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Peter Weinberger <pjw@google.com>
TestBlockProfile currently requires exactly five PCs in each sample.
With more aggressive inlining there may be fewer, so change this test
to use the same pattern as TestMutexProfile, which accepts one or more
PCs. With this change, this test passes when compiled with -l=4.
Change-Id: I1421a6d56c96b77111bdc671d88723a222672fd6
Reviewed-on: https://go-review.googlesource.com/41110
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Lazar <lazard@golang.org>
CL 40876 changed ExampleFrames so that the output
was stable with and without mid-stack inlining.
However, that change lost some of the
pedagogical and copy/paste value of the example.
It was unclear why both more and i were being tracked,
and whether the 5 in i < 5 is related to len(pc),
and if so, why and how.
This CL rewrites the example with lots more comments,
and such that the core structure more closely matches
normal usage, and such that it is obvious
which lines of code should be deleted when copying.
As a bonus, it also now illustrates Frame.File.
Change-Id: Iab73541dd096657ddf79c5795337e8b596d89740
Reviewed-on: https://go-review.googlesource.com/41136
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
The period recorded in CPU profiles is in nanoseconds, but was being
computed incorrectly as hz * 1000. As a result, many absolute times
displayed by pprof were incorrect.
Fix this by computing the period correctly.
Change-Id: I6fadd6d8ad3e57f31e8cc7a25a24fcaec510d8d4
Reviewed-on: https://go-review.googlesource.com/40995
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Convert the parsed attribute name to lowercase before checking its value in
the HTML parser state machine. This ensures that the type attribute in
the script element is handled in a case-sensitive manner, just like all
other attribute names.
Fixes#19965
Change-Id: I806d8c62aada2c3b5b4328aff75f217ea60cb339
Reviewed-on: https://go-review.googlesource.com/40650
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
VEX encoded instructions don't have a REX byte, so for PC relative
addressing we don't need to recalculate relocation offset.
Fixes#19518
Change-Id: Icf5414962de4350d76fd220817498337f90614fc
Reviewed-on: https://go-review.googlesource.com/38138
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Handle MIME types found in the type attribute of the script element
in a case insensitive way, as per Section 5.1 of RFC 2045.
Fixes#19968
Change-Id: Ie1416178c937dcf2c96bcec4191cebe7c3477af8
Reviewed-on: https://go-review.googlesource.com/40702
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This updates PPC64.rules to include rules to generate rotates
for ADD, OR, XOR operators that combine two opposite shifts
that sum to 32 or 64.
To support this change opcodes for ROTL and ROTLW were added to
be used like the rotldi and rotlwi extended mnemonics.
This provides the following improvement in sha3:
BenchmarkPermutationFunction-8 302.83 376.40 1.24x
BenchmarkSha3_512_MTU-8 98.64 121.92 1.24x
BenchmarkSha3_384_MTU-8 136.80 168.30 1.23x
BenchmarkSha3_256_MTU-8 169.21 211.29 1.25x
BenchmarkSha3_224_MTU-8 179.76 221.19 1.23x
BenchmarkShake128_MTU-8 212.87 263.23 1.24x
BenchmarkShake256_MTU-8 196.62 245.60 1.25x
BenchmarkShake256_16x-8 163.57 194.37 1.19x
BenchmarkShake256_1MiB-8 199.02 248.74 1.25x
BenchmarkSha3_512_1MiB-8 106.55 133.13 1.25x
Fixes#20030
Change-Id: I484c56f48395d32f53ff3ecb3ac6cb8191cfee44
Reviewed-on: https://go-review.googlesource.com/40992
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Instead of populating the aux symbol
of CALLudiv during rewrite rules,
populate it during genssa.
This simplifies the rewrite rules.
It also removes all remaining calls
to ctxt.Lookup from any rewrite rules.
This is a first step towards removing
ctxt from ssa.Cache entirely,
and also a first step towards converting
the obj.LSym.Version field into a boolean.
It should also speed up compilation.
Also, move func udiv into package runtime.
That's where it is anyway,
and it lets udiv look and act like the rest of
the runtime support functions.
Change-Id: I41462a632c14fdc41f61b08049ec13cd80a87bfe
Reviewed-on: https://go-review.googlesource.com/41191
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
As of CL 39998, it is no longer necessary.
Fixes#19699
Change-Id: Ie1c49c8468073c6ddeb96c03668705cf81d40c98
Reviewed-on: https://go-review.googlesource.com/41051
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
ld.ldelf contained a mixture of normal and C style, goto bad, error
handling. The use of goto requires many variables to be declared well
before their use which inhibited further refactoring to this method.
This CL removes the gotos in this function. Future CLs will address
remainder of the C style function scoped declarations in this function.
Change-Id: Ib9def495209a2f8deb11dcf30ee954bca95390c6
Reviewed-on: https://go-review.googlesource.com/41172
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
obj.Linksymfmt is no longer referenced by any packages in cmd/...
Change-Id: Id4d9213d1577e13580b60755dbf7da313b17cb0e
Reviewed-on: https://go-review.googlesource.com/41171
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The dclstack is now a proper stack and thus we can implement it
using a slice rather than a linked list.
Change-Id: I200e85621ff76c111bdeb7eb382fd82da438f3ba
Reviewed-on: https://go-review.googlesource.com/41135
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
- PkgMap was only needed to test import/export in a "cleanroom"
environment, with debugFormat set. Provided helper function
instead.
- PkgList was only used to identify directly imported packages.
Instead, compute that list explicitly from the package map.
It happens only once, the list is small, and it's more robust
than keeping two data structures in sync.
Change-Id: I82dce3c0b5cb816faae58708e877799359c20fcb
Reviewed-on: https://go-review.googlesource.com/41078
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
There's already special code to access it.
Change-Id: I28ca4f44a04262407ee9f1c826ada4e7eba44775
Reviewed-on: https://go-review.googlesource.com/41073
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
That's where it belongs. Also, moved pkgMap and pkgs globals.
Change-Id: I531727fe5ce162c403efefec82f4cc90afa326d7
Reviewed-on: https://go-review.googlesource.com/41071
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Returns at the end of func bodies where the funcs have no return values
are pointless.
Change-Id: I0da5ea78671503e41a9f56dd770df8c919310ce5
Reviewed-on: https://go-review.googlesource.com/41093
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Such dead code is legitimate when dealing with arch-specific
types (int, uint, uintptr).
The CL removes the majority of 'too small for shift' false positives
from such a code.
Change-Id: I62c5635a1d3774ab2d71d3d7056f0589f214cbe5
Reviewed-on: https://go-review.googlesource.com/38065
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
When we switched to SSA R0 was made allocatable and no longer holds
zero on s390x.
Change-Id: I1c752bb02da35462a535492379345fa9f4e12cb0
Reviewed-on: https://go-review.googlesource.com/41079
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This displays the swept and reclaimed bytes for sweep events in the
lower panel of the trace viewer.
Change-Id: If1665a1c02bbc47700e0d9f515e574f013f3f285
Reviewed-on: https://go-review.googlesource.com/40812
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
This extends the GCSweepDone event with counts of swept and reclaimed
bytes. These are useful for understanding the duration and
effectiveness of sweep events.
Change-Id: I3c97a4f0f3aad3adbd188adb264859775f54e2df
Reviewed-on: https://go-review.googlesource.com/40811
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Currently, each individual span sweep emits a span to the trace. But
sweeps are generally done in loops until some condition is satisfied,
so this tracing is lower-level than anyone really wants any hides the
fact that no other work is being accomplished between adjacent sweep
events. This is also high overhead: enabling tracing significantly
impacts sweep latency.
Replace this with instead tracing around the sweep loops used for
allocation. This is slightly tricky because sweep loops don't
generally know if any sweeping will happen in them. Hence, we make the
tracing lazy by recording in the P that we would like to start tracing
the sweep *if* one happens, and then only closing the sweep event if
we started it.
This does mean we don't get tracing on every sweep path, which are
legion. However, we get much more informative tracing on the paths
that block allocation, which are the paths that matter.
Change-Id: I73e14fbb250acb0c9d92e3648bddaa5e7d7e271c
Reviewed-on: https://go-review.googlesource.com/40810
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Changes the text to match GOOS which appends 'and so on' at the
end to avoid restricting the set of possible values.
Change-Id: I54bcde71334202cf701662cdc2582c974ba8bf53
Reviewed-on: https://go-review.googlesource.com/41074
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Patch from Vlad Krasnov and confirmed to be under CLA.
Fixes#20040.
Change-Id: Ieb8436c4dcb6669a1620f1e0d257efd047b1b87c
Reviewed-on: https://go-review.googlesource.com/41070
Run-TryBot: Adam Langley <agl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
When allocating a non-small array of buckets for a map,
also preallocate some overflow buckets.
The estimate of the number of overflow buckets
is based on a simulation of putting mid=(low+high)/2 elements
into a map, where low is the minimum number of elements
needed to reach this value of b (according to overLoadFactor),
and high is the maximum number of elements possible
to put in this value of b (according to overLoadFactor).
This estimate is surprisingly reliable and accurate.
The number of overflow buckets needed is quadratic,
for a fixed value of b.
Using this mid estimate means that we will overallocate a few
too many overflow buckets when the actual number of elements is near low,
and underallocate significantly too few overflow buckets
when the actual number of elements is near high.
The mechanism introduced in this CL can be re-used for
other overflow bucket optimizations.
For example, given an initial size hint,
we could estimate quite precisely the number of overflow buckets.
This is #19931.
We could also change from "non-nil means end-of-list"
to "pointer-to-hmap.buckets means end-of-list",
and then create a linked list of reusable overflow buckets
when they are freed by map growth.
That is #19992.
We could also use a similar mechanism to do bulk allocation
of overflow buckets.
All these uses can co-exist with only the one additional pointer
in mapextra, given a little care.
name old time/op new time/op delta
MapPopulate/1-8 60.1ns ± 2% 60.3ns ± 2% ~ (p=0.278 n=19+20)
MapPopulate/10-8 577ns ± 1% 578ns ± 1% ~ (p=0.140 n=20+20)
MapPopulate/100-8 8.06µs ± 1% 8.19µs ± 1% +1.67% (p=0.000 n=20+20)
MapPopulate/1000-8 104µs ± 1% 104µs ± 1% ~ (p=0.317 n=20+20)
MapPopulate/10000-8 891µs ± 1% 888µs ± 1% ~ (p=0.101 n=19+20)
MapPopulate/100000-8 8.61ms ± 1% 8.58ms ± 0% -0.34% (p=0.009 n=20+17)
name old alloc/op new alloc/op delta
MapPopulate/1-8 0.00B 0.00B ~ (all equal)
MapPopulate/10-8 179B ± 0% 179B ± 0% ~ (all equal)
MapPopulate/100-8 3.33kB ± 0% 3.38kB ± 0% +1.48% (p=0.000 n=20+16)
MapPopulate/1000-8 55.5kB ± 0% 53.4kB ± 0% -3.84% (p=0.000 n=19+20)
MapPopulate/10000-8 432kB ± 0% 428kB ± 0% -1.06% (p=0.000 n=19+20)
MapPopulate/100000-8 3.65MB ± 0% 3.62MB ± 0% -0.70% (p=0.000 n=20+20)
name old allocs/op new allocs/op delta
MapPopulate/1-8 0.00 0.00 ~ (all equal)
MapPopulate/10-8 1.00 ± 0% 1.00 ± 0% ~ (all equal)
MapPopulate/100-8 18.0 ± 0% 17.0 ± 0% -5.56% (p=0.000 n=20+20)
MapPopulate/1000-8 96.0 ± 0% 72.6 ± 1% -24.38% (p=0.000 n=20+20)
MapPopulate/10000-8 625 ± 0% 319 ± 0% -48.86% (p=0.000 n=20+20)
MapPopulate/100000-8 6.23k ± 0% 4.00k ± 0% -35.79% (p=0.000 n=20+20)
Change-Id: I01f41cb1374bdb99ccedbc00d04fb9ae43daa204
Reviewed-on: https://go-review.googlesource.com/40979
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Any change to how we allocate overflow buckets
will require some extra hmap storage,
but we don't want hmap to grow,
particular as small maps usually don't need overflow buckets.
This CL converts the existing hmap overflow field,
which is usually used for pointer-free maps,
into a generic extra field.
This extra field can be used to hold data that is optional.
If it is valuable enough to do have special
handling of overflow buckets, which are medium-sized,
it is valuable enough to pay an extra alloc and two extra words for.
Adding fields to extra would entail adding overhead to pointer-free maps;
any mapextra fields added would need to be weighed against that.
This CL is just rearrangement, though.
Updates #19931
Updates #19992
Change-Id: If8537a206905b9d4dc6cd9d886184ece671b3f80
Reviewed-on: https://go-review.googlesource.com/40976
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This simplifies the code, as well as providing
a single place to modify to change the
allocation of new overflow buckets.
Updates #19931
Updates #19992
Change-Id: I77070619f5c8fe449bbc35278278bca5eda780f2
Reviewed-on: https://go-review.googlesource.com/40975
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
goobj.importPathToPrefix is 3x faster than gc.pathToPrefix so rename and
move it to cmd/internal/objabi which is already imported by both goobj and
gc.
Change-Id: I10eda5bce95ef6d5d888818c5c47258c2833ea45
Reviewed-on: https://go-review.googlesource.com/40875
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The last use of condOps was removed in c644a76.
Change-Id: I5383d0e7a9078fc17ca12ed032ecf8e7f4aa95d7
Reviewed-on: https://go-review.googlesource.com/41030
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Replace derecursed postorder computation with one that
mimics DFS traversal.
Corrected outerinner function in loopfinder
Leave enhanced checks in place.
Change-Id: I657ba5e89c88941028d6d4c72e9f9056e30f1ce8
Reviewed-on: https://go-review.googlesource.com/40872
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Follow-up on https://go-review.googlesource.com/#/c/39998/
which dropped this information.
The reported blocks are the innermost blocks containing a
label jumped to from outside, not the outermost block as
reported originally by cmd/compile.
We could report the outermost block with a slighly more
involved algorithm (need to track containing blocks for
all unresolved forward gotos), but since gccgo also reports
the innermost blocks, the current approach seems good enough.
Change-Id: Ic0235b8fafe8d5f99dc9872b58e90e8d9e72c5db
Reviewed-on: https://go-review.googlesource.com/40980
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
