CL 228106 moved the position at which we
checked whether a type switch variable had a particular type
from the type switch to the case statement, but only for
single, concrete types. This is a better position,
so this change changes the rest.
Change-Id: I601d4a5c4a0d9400e7804b9f1e729af948349a8f
Reviewed-on: https://go-review.googlesource.com/c/go/+/228220
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
This lets us provide a better position in its use in swt.go.
Change-Id: I7c0da6bd0adea81acfc9a591e6a01b241a5e0942
Reviewed-on: https://go-review.googlesource.com/c/go/+/228219
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Consider
switch x:= x.(type) {
case int:
// int stmts
case error:
// error stmts
}
Prior to this change, we lowered this roughly as:
if x, ok := x.(int); ok {
// int stmts
} else if x, ok := x.(error); ok {
// error stmts
}
x, ok := x.(error) is implemented with a call to runtime.assertE2I2 or runtime.assertI2I2.
x, ok := x.(int) generates inline code that checks whether x has type int,
and populates x and ok as appropriate. We then immediately branch again on ok.
The shortcircuit pass in the SSA backend is designed to recognize situations
like this, in which we are immediately branching on a bool value
that we just calculated with a branch.
However, the shortcircuit pass has limitations when the intermediate state has phis.
In this case, the phi value is x (the int).
CL 222923 improved the situation, but many cases are still unhandled.
I have further improvements in progress, which is how I found this particular problem,
but they are expensive, and may or may not see the light of day.
In the common case of a lone concrete type in a type switch case,
it is easier and cheaper to simply lower a different way, roughly:
if _, ok := x.(int); ok {
x := x.(int)
// int stmts
}
Instead of using a type assertion, though, we extract the value of x
from the interface directly.
This removes the need to track x (the int) across the branch on ok,
which removes the phi, which lets the shortcircuit pass do its job.
Benchmarks for encoding/binary show improvements, as well as some
wild swings on the super fast benchmarks (alignment effects?):
name old time/op new time/op delta
ReadSlice1000Int32s-8 5.25µs ± 2% 4.87µs ± 3% -7.11% (p=0.000 n=44+49)
ReadStruct-8 451ns ± 2% 417ns ± 2% -7.39% (p=0.000 n=45+46)
WriteStruct-8 412ns ± 2% 405ns ± 3% -1.58% (p=0.000 n=46+48)
ReadInts-8 296ns ± 8% 275ns ± 3% -7.23% (p=0.000 n=48+50)
WriteInts-8 324ns ± 1% 318ns ± 2% -1.67% (p=0.000 n=44+49)
WriteSlice1000Int32s-8 5.21µs ± 2% 4.92µs ± 1% -5.67% (p=0.000 n=46+44)
PutUint16-8 0.58ns ± 2% 0.59ns ± 2% +0.63% (p=0.000 n=49+49)
PutUint32-8 0.87ns ± 1% 0.58ns ± 1% -33.10% (p=0.000 n=46+44)
PutUint64-8 0.66ns ± 2% 0.87ns ± 2% +33.07% (p=0.000 n=47+48)
LittleEndianPutUint16-8 0.86ns ± 2% 0.87ns ± 2% +0.55% (p=0.003 n=47+50)
LittleEndianPutUint32-8 0.87ns ± 1% 0.87ns ± 1% ~ (p=0.547 n=45+47)
LittleEndianPutUint64-8 0.87ns ± 2% 0.87ns ± 1% ~ (p=0.451 n=46+47)
ReadFloats-8 79.8ns ± 5% 75.9ns ± 2% -4.83% (p=0.000 n=50+47)
WriteFloats-8 89.3ns ± 1% 88.9ns ± 1% -0.48% (p=0.000 n=46+44)
ReadSlice1000Float32s-8 5.51µs ± 1% 4.87µs ± 2% -11.74% (p=0.000 n=47+46)
WriteSlice1000Float32s-8 5.51µs ± 1% 4.93µs ± 1% -10.60% (p=0.000 n=48+47)
PutUvarint32-8 25.9ns ± 2% 24.0ns ± 2% -7.02% (p=0.000 n=48+50)
PutUvarint64-8 75.1ns ± 1% 61.5ns ± 2% -18.12% (p=0.000 n=45+47)
[Geo mean] 57.3ns 54.3ns -5.33%
Despite the rarity of type switches, this generates noticeably smaller binaries.
file before after Δ %
addr2line 4413296 4409200 -4096 -0.093%
api 5982648 5962168 -20480 -0.342%
cgo 4854168 4833688 -20480 -0.422%
compile 19694784 19682560 -12224 -0.062%
cover 5278008 5265720 -12288 -0.233%
doc 4694824 4682536 -12288 -0.262%
fix 3411336 3394952 -16384 -0.480%
link 6721496 6717400 -4096 -0.061%
nm 4371152 4358864 -12288 -0.281%
objdump 4760960 4752768 -8192 -0.172%
pprof 14810820 14790340 -20480 -0.138%
trace 11681076 11668788 -12288 -0.105%
vet 8285464 8244504 -40960 -0.494%
total 115824120 115627576 -196544 -0.170%
Compiler performance is marginally improved (note that go/types has many type switches):
name old alloc/op new alloc/op delta
Template 35.0MB ± 0% 35.0MB ± 0% +0.09% (p=0.008 n=5+5)
Unicode 28.5MB ± 0% 28.5MB ± 0% ~ (p=0.548 n=5+5)
GoTypes 114MB ± 0% 114MB ± 0% -0.76% (p=0.008 n=5+5)
Compiler 541MB ± 0% 541MB ± 0% -0.03% (p=0.008 n=5+5)
SSA 1.17GB ± 0% 1.17GB ± 0% ~ (p=0.841 n=5+5)
Flate 21.9MB ± 0% 21.9MB ± 0% ~ (p=0.421 n=5+5)
GoParser 26.9MB ± 0% 26.9MB ± 0% ~ (p=0.222 n=5+5)
Reflect 74.6MB ± 0% 74.6MB ± 0% ~ (p=1.000 n=5+5)
Tar 32.9MB ± 0% 32.8MB ± 0% ~ (p=0.056 n=5+5)
XML 42.4MB ± 0% 42.1MB ± 0% -0.77% (p=0.008 n=5+5)
[Geo mean] 73.2MB 73.1MB -0.15%
name old allocs/op new allocs/op delta
Template 377k ± 0% 377k ± 0% +0.06% (p=0.008 n=5+5)
Unicode 354k ± 0% 354k ± 0% ~ (p=0.095 n=5+5)
GoTypes 1.31M ± 0% 1.30M ± 0% -0.73% (p=0.008 n=5+5)
Compiler 5.44M ± 0% 5.44M ± 0% -0.04% (p=0.008 n=5+5)
SSA 11.7M ± 0% 11.7M ± 0% ~ (p=1.000 n=5+5)
Flate 239k ± 0% 239k ± 0% ~ (p=1.000 n=5+5)
GoParser 302k ± 0% 302k ± 0% -0.04% (p=0.008 n=5+5)
Reflect 977k ± 0% 977k ± 0% ~ (p=0.690 n=5+5)
Tar 346k ± 0% 346k ± 0% ~ (p=0.889 n=5+5)
XML 431k ± 0% 430k ± 0% -0.25% (p=0.008 n=5+5)
[Geo mean] 806k 806k -0.10%
For packages with many type switches, this considerably shrinks function text size.
Some examples:
file before after Δ %
encoding/binary.s 30726 29504 -1222 -3.977%
go/printer.s 77597 76005 -1592 -2.052%
cmd/vendor/golang.org/x/tools/go/ast/astutil.s 65704 63318 -2386 -3.631%
cmd/vendor/golang.org/x/tools/go/analysis/passes/unreachable.s 8047 7714 -333 -4.138%
Text size regressions are rare.
Change-Id: Ic10982bbb04876250eaa5bfee97990141ae5fc28
Reviewed-on: https://go-review.googlesource.com/c/go/+/228106
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
In the dev.link branch we continued developing the new object
file format support and the linker improvements described in
https://golang.org/s/better-linker . Since the last merge, more
progress has been made to improve the new linker.
This is a clean merge, as we already merged master branch to
dev.link first.
Change-Id: I1fef2b1d94bd2410001142da8991544da5ee896d
ascompatee does not generate 'x = x' during return, so we don't have to
check for samelist and disguising special return anymore.
While at it, also remove samelist, as this is the only place it's used.
Passes toolstash-check.
Change-Id: I41c7b077d562aadb5916a61e2ab6229bae3cdef4
Reviewed-on: https://go-review.googlesource.com/c/go/+/227807
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Currently this CL has no effect because V == x.typ in the affected
code. But if we should ever manipulate V (e.g., to support some form
of lazy evaluation of the type), not using V consistently would
lead to a subtle bug.
Change-Id: I465e72d18bbd2b6cd8fcbd746e0d28d14f758c03
Reviewed-on: https://go-review.googlesource.com/c/go/+/228105
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Quote original values passed as substring of ParseError.Message.
Improves the user experience of ParseDuration by making it
quote its original argument, for example:
_, err := time.ParseDuration("for breakfast")
will now produce an error, which when printed out is:
time: invalid duration "for breakfast"
instead of:
time: invalid duration for breakfast
Adapt test cases for format.Parse and format.ParseDuration.
Fixes#38295
Change-Id: Ife322c8f3c859e1e4e8dd546d4cf0d519b4bfa81
Reviewed-on: https://go-review.googlesource.com/c/go/+/227878
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This reverts CL 224588.
Reason for revert: Test failing on secondary platforms.
Change-Id: Ic15fdc73a0d2b860e776733abb82c58809e13160
Reviewed-on: https://go-review.googlesource.com/c/go/+/228200
Reviewed-by: Ian Lance Taylor <iant@golang.org>
- CopyN: 5 creates ambiguity with respect to whitespace and upperbound
- TeeReader less boilerplate and displays a common usage of it
- SectionReader_* all sections unified to 5:17 for clarity
- SectionReader_Seek uses io.Copy to stdout like other examples
- Seeker_Seek remove useless prints
- Pipe print reader like other examples
Updates #36417
Change-Id: Ibd01761d5a5786cdb1ea934f7a98f8302430c8a5
GitHub-Last-Rev: 4c17f9a8e3
GitHub-Pull-Request: golang/go#38379
Reviewed-on: https://go-review.googlesource.com/c/go/+/227868
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We split the output into blocks and write them in parallel. The
block boundary is placed at symbol boundary. In the case of outer
symbols and sub symbols, currently we may split an outer symbol
into two blocks. This will be bad, as the two blocks will have
overlapping address range, since outer symbol and its sub symbols
occupies the same address range.
Make sure we place block boundary only at top-level symbol
boundaries.
Fix boringcrypto build.
Change-Id: I56811d3969c65c6be97672d8e1f1ea36b2447465
Reviewed-on: https://go-review.googlesource.com/c/go/+/227957
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
(cherry picked from commit 636fa3148f)
Reviewed-on: https://go-review.googlesource.com/c/go/+/228138
If -d=ssa/PASS/debug=N is specified (N >= 2) for a rewrite pass
(e.g. lower), when a Value (or Block) is rewritten, print the
Value (or Block) before and after.
For #31915.
Updates #19013.
Change-Id: I80eadd44302ae736bc7daed0ef68529ab7a16776
Reviewed-on: https://go-review.googlesource.com/c/go/+/176718
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Importing the time/tzdata package will embed a copy of the IANA
timezone database into the program. This will let the program work
correctly when the timezone database is not available on the system.
It will increase the size of the binary by about 800K.
You can also build a program with -tags timetzdata to embed the
timezone database in the program being built.
Fixes#21881Fixes#38013Fixes#38017
Change-Id: Iffddee72a8f46c95fee3bcde43c142d6899d9246
Reviewed-on: https://go-review.googlesource.com/c/go/+/224588
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Following CL 226818, the compiler will allow inlining a single cycle in
an inline chain. Immediately-recursive functions are still disallowed,
which is what this heuristic refers to.
Add a regression test for this case.
Note that in addition to this check, if the compiler were to inline
multiple cycles via a loop (i.e., rather than appending duplicate code),
much more work would be required here to handle a single address
appearing in multiple different inline frames.
Updates #29737
Change-Id: I88de15cfbeabb9c04381e1c12cc36778623132a5
Reviewed-on: https://go-review.googlesource.com/c/go/+/227346
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
TestTryAdd is particularly brittle because it tests some real cases by
constructing fake sample stack frames. If those frames don't correctly
represent what the runtime would generate then they may fail to catch
regressions.
Instead, call runtime.Callers at the bottom of real function calls to
generate real frames as a base for truncation, etc in tests. Several of
these tests still have to fake parts of the frames to test the right
thing, but this is a bit less fragile.
This change is equivalent to the original
0dfb0513ec (golang.org/cl/227484), except
that the test skips if the test functions aren't inline (e.g., noopt
builders).
Change-Id: Ie9e32b5660cfe28a924f9cfcddcd887ea2effd66
Reviewed-on: https://go-review.googlesource.com/c/go/+/227922
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
The parameter name is dt, not t. Also, line-wrap the godoc comment.
Change-Id: Ie012d2a5680525b88e244a3380d72bc4f61da8e7
Reviewed-on: https://go-review.googlesource.com/c/go/+/228058
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matt Layher <mdlayher@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
It is no longer used. The only remaining use is in generating
Plan 9 debug info, which is already not supported.
Change-Id: Ia023d6f2fa7d57b97ba861ce464e2eec8ac2d1f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/228142
Reviewed-by: Than McIntosh <thanm@google.com>
lib.Textp was used for text address assignment and trampoline
insertion. Now that it has been converted to using the loader,
no need to populate lib.Textp.
Port the logic of canonicalizing dupok symbol's package to the
loader.
unit.Textp was used for DWARF generation, which has also been
converted to using the loader.
Change-Id: I22d4dd30a52a29dd5b1b7b795d43a19f6215e4ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/228140
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Mark nextFreeFast as not inline, as it is too expensive to inline on riscv64.
Also remove riscv64 from non-atomic inline architectures, as we now have
atomic intrisics.
Updates #22239
Change-Id: I6e0e72c1192070e39f065bee486f48df4cc74b35
Reviewed-on: https://go-review.googlesource.com/c/go/+/227808
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The taskid mode is based on the goroutine-oriented trace view,
which displays each goroutine as a separate row. This is good when
inspecting the interaction and timeline among related goroutines,
and the user region information (associated with each goroutine)
in detail, but when many goroutines are involved, this mode does
not scale.
The focustask mode is based on the default trace view with the
user task hierarchy at the top. Each row is a P and there are only
a handful number of Ps in most cases, so browsers can handle
this mode more gracefully. But, I had difficulty in displaying
the user region information (because a goroutine can start/stop/
migrate across Ps, and visualizing the stack of regions nicely
was complicated). It may be doable, but it's a work.
This CL surfaces the hidden focustask mode. Moreover, use it
as the default user task view mode. The taskid mode can be still
accessible through 'goroutine view' links.
Unlike taskid-based user annotation view that extends goroutine-based
trace view, the focustask view
Change-Id: Ib691a5e1dd14695fa70a0ae67bff62817025e8c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/227921
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
As we have converted the pclntab generation, FuncInfo is not
needed after. No need to load it.
Change-Id: Idcfe4da44dfc94d8d44509d12179b354a2e295e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/228139
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Otherwise, just copying the aux and auxint fields doesn't make much sense.
(Although there's no bug - it just means it isn't typechecked correctly.)
Change-Id: I4e21ac67f0c7bfd04ed5af1713cd24bca08af092
Reviewed-on: https://go-review.googlesource.com/c/go/+/227962
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Fix a bug in findfunctab when building plugin on Darwin (this is
a regression introduced by CL 227842).
Change-Id: Ic610168e45a750c0a2f2b8611d5d9154e6c2622f
Reviewed-on: https://go-review.googlesource.com/c/go/+/228137
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
HWCap and HWCap2 are no longer linknamed into package runtime. Also,
merge two sentences both starting with "These are..." and don't mention
any file name where archauxv is defined, as it become outdated if
support for a new $GOOS/$GOARCH combination is added. This is e.g.
already the case for arm64, where archauxv is also defined for
freebsd/arm64.
Change-Id: I9314a66633736b12e777869a832d8b79d442a6f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/228057
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The repository of delve has already switched from the personal
account github.com/derekparker/delve to the organization account
github.com/go-delve/delve. According to go-delve/delve#1456.
Change-Id: Ie64f72c2808a8aca5059a75e2c2f11d8691e66b3
GitHub-Last-Rev: f90120c3b3
GitHub-Pull-Request: golang/go#38387
Reviewed-on: https://go-review.googlesource.com/c/go/+/227999
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run TestLogOpt for riscv64 on amd64, as is done for other architectures.
This would have caught the test failure on riscv64 introduced in
47ade08141.
Change-Id: If29dea2ef383b087154d046728f6d1c96811f5a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/227806
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Remove the loader's AttrContainer method, since it is no longer
needed. All of the code in the linker that used s.Attr.Container() is
now upstream of loadlibfull(), and the code in question now uses local
bitmaps to keep track of container text symbols as opposed to loader
methods.
Change-Id: Iae956d24bef2776e181c3b8208476dcb0b9a2916
Reviewed-on: https://go-review.googlesource.com/c/go/+/227959
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
The pclntab phase generates a series of "inltree.*" symbols with
inlining related pcdata; these symbols previously were given names and
enterered into the symbol lookup table, but there is no real reason to
do this, since they never need to be looked up when pcln generation is
done. Switch them over to anonymous symbols.
So as to insure that the later symtab phase picks them up correctly,
assign them a type of SGOFUNC instead of SRODATA, and change symtab to
look for this when assigning symbols to groups.
Change-Id: I38225dbb130ad7aea5d16f79cef3d8d388c61c2b
Reviewed-on: https://go-review.googlesource.com/c/go/+/227845
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Convert the linker's findfunctab phase to use the new loader APIs.
Change-Id: Ia980a85963fe2e7c554c212c0cc89208272264bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/227842
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Surprisingly many rules needed no modification.
Use wrapper functions for aux like we did for auxint.
Simplifies things a bit.
Change-Id: I2e852e77f1585dcb306a976ab9335f1ac5b4a770
Reviewed-on: https://go-review.googlesource.com/c/go/+/227961
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Log large copies in the riscv64 compiler.
This was missed in 47ade08141, resulting in
the new test added to cmd/compile/internal/logopt failing on riscv64.
Change-Id: I6f763e86f42834148e911d16928f9fbabcfa4290
Reviewed-on: https://go-review.googlesource.com/c/go/+/227804
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
We split the output into blocks and write them in parallel. The
block boundary is placed at symbol boundary. In the case of outer
symbols and sub symbols, currently we may split an outer symbol
into two blocks. This will be bad, as the two blocks will have
overlapping address range, since outer symbol and its sub symbols
occupies the same address range.
Make sure we place block boundary only at top-level symbol
boundaries.
Fix boringcrypto build.
Change-Id: I56811d3969c65c6be97672d8e1f1ea36b2447465
Reviewed-on: https://go-review.googlesource.com/c/go/+/227957
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Adds an entry in the Go1.15 release notes, but also
adds an example test for URL.Redacted.
Follow-up of CL 207082.
Updates #37419
Change-Id: Ibf81989778907511a3a3a3e4a03d1802b5dd9762
Reviewed-on: https://go-review.googlesource.com/c/go/+/227997
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
