Currently, mhdr/methods is emitted with the same len/cap. There's no way
to distinguish between exported and non-exported methods statically.
This CL splits mhdr/methods into two parts, use "len" for number of
exported methods, and "cap" for all methods. This fixes the bug in
issue #22075, which intends to return the number of exported methods but
currently return all methods.
Note that with this encoding, we still can access either
all/exported-only/non-exported-only methods:
mhdr[:cap(mhdr)] // all methods
mhdr // exported methods
mhdr[len(mhdr):cap(mhdr)] // non-exported methods
Thank to Matthew Dempsky (@mdempsky) for suggesting this encoding.
Fixes#22075
Change-Id: If662adb03ccff27407d55a5578a0ed05a15e7cdd
Reviewed-on: https://go-review.googlesource.com/c/go/+/259237
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Fixes#40281
Change-Id: Ie624bce3a78a06d7ed71bba1f501e66802dffd13
Reviewed-on: https://go-review.googlesource.com/c/go/+/248341
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Dmitri Shuralyov <dmitshur@golang.org>
My last 387 CL. So sad ... ... ... ... not!
Fixes#40255
Change-Id: I8d4ddb744b234b8adc735db2f7c3c7b6d8bbdfa4
Reviewed-on: https://go-review.googlesource.com/c/go/+/258957
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
For #41737
Change-Id: Id065880dd7da54dec1b45662c202aeb7f8397c60
Reviewed-on: https://go-review.googlesource.com/c/go/+/258819
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
In the common case (<1KB types), no allocation is required
by reflect.Zero.
Also use memclr instead of memmove in Set when the source
is known to be zero.
Fixes#33136
Change-Id: Ic66871930fbb53328032e587153ebd12995ccf55
Reviewed-on: https://go-review.googlesource.com/c/go/+/192331
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Currently, we include a "kind" field on scase to distinguish the three
kinds of cases in a select statement: sends, receives, and defaults.
This commit removes by kind field by instead arranging for the
compiler to always place sends before receives, and to provide their
counts separately. It also passes an explicit "block bool" parameter
to avoid needing to include a default case in the array.
It's safe to shuffle cases like this because the runtime will
randomize the order they're polled in anyway.
Fixes#40410.
Change-Id: Iaeaed4cf7bddd576d78f2c863bd91a03a5c82df2
Reviewed-on: https://go-review.googlesource.com/c/go/+/245125
Reviewed-by: Keith Randall <khr@golang.org>
We aren't using it for anything. The visited map will terminate
any recursion for us.
Change-Id: I36e6bd8e34952123c2ed46323067e42928ec7168
Reviewed-on: https://go-review.googlesource.com/c/go/+/238759
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Currently, the GC stores the object marks for checkmarks mode in the
heap bitmap using a rather complex encoding: for one word objects, the
checkmark is stored in the pointer/scalar bit since one word objects
must be pointers; for larger objects, the checkmark is stored in what
would be the scan/dead bit for the second word of the object. This
encoding made more sense when the runtime used the first scan/dead bit
as the regular mark bit, but we moved away from that long ago.
This encoding and overloading of the heap bitmap bits causes a great
deal of complexity in many parts of the allocator and garbage
collector and leads to some subtle bugs like #15903.
This CL moves the checkmarks mark bits into their own per-arena bitmap
and reclaims the second scan/dead bit as a regular scan/dead bit.
I tested this by enabling doubleCheck mode in heapBitsSetType and
running in both regular and GODEBUG=gccheckmark=1 mode.
Fixes#15903.
No performance degradation. (Very slight improvement on a few
benchmarks, but it's probably just noise.)
name old time/op new time/op delta
BiogoIgor 16.6s ± 1% 16.4s ± 1% -0.94% (p=0.000 n=25+24)
BiogoKrishna 19.2s ± 3% 19.2s ± 3% ~ (p=0.638 n=23+25)
BleveIndexBatch100 6.12s ± 5% 6.17s ± 4% ~ (p=0.170 n=25+25)
CompileTemplate 206ms ± 1% 205ms ± 1% -0.43% (p=0.005 n=24+24)
CompileUnicode 82.2ms ± 2% 81.5ms ± 2% -0.95% (p=0.001 n=22+22)
CompileGoTypes 755ms ± 3% 754ms ± 4% ~ (p=0.715 n=25+25)
CompileCompiler 3.73s ± 1% 3.73s ± 1% ~ (p=0.445 n=25+24)
CompileSSA 8.67s ± 1% 8.66s ± 1% ~ (p=0.836 n=24+22)
CompileFlate 134ms ± 2% 133ms ± 1% -0.66% (p=0.001 n=24+23)
CompileGoParser 164ms ± 1% 163ms ± 1% -0.85% (p=0.000 n=24+24)
CompileReflect 466ms ± 5% 466ms ± 3% ~ (p=0.863 n=25+25)
CompileTar 182ms ± 1% 182ms ± 1% -0.31% (p=0.048 n=24+24)
CompileXML 249ms ± 1% 248ms ± 1% -0.32% (p=0.031 n=21+25)
CompileStdCmd 10.3s ± 1% 10.3s ± 1% ~ (p=0.459 n=23+23)
FoglemanFauxGLRenderRotateBoat 8.66s ± 1% 8.62s ± 1% -0.47% (p=0.000 n=23+24)
FoglemanPathTraceRenderGopherIter1 20.3s ± 3% 20.2s ± 2% ~ (p=0.893 n=25+25)
GopherLuaKNucleotide 29.7s ± 1% 29.8s ± 2% ~ (p=0.421 n=24+25)
MarkdownRenderXHTML 246ms ± 1% 247ms ± 1% ~ (p=0.558 n=25+24)
Tile38WithinCircle100kmRequest 779µs ± 4% 779µs ± 3% ~ (p=0.954 n=25+25)
Tile38IntersectsCircle100kmRequest 1.02ms ± 3% 1.01ms ± 4% ~ (p=0.658 n=25+25)
Tile38KNearestLimit100Request 984µs ± 4% 986µs ± 4% ~ (p=0.627 n=24+25)
[Geo mean] 552ms 551ms -0.19%
https://perf.golang.org/search?q=upload:20200723.6
Change-Id: Ic703f26a83fb034941dc6f4788fc997d56890dec
Reviewed-on: https://go-review.googlesource.com/c/go/+/244539
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Adds parentheses so as to properly bind <- to the right most
channel.
This meant that previously given:
ChanOf(<-chan T)
it would mistakenly try to look up the type as
chan <-chan T
instead of
chan (<-chan T)
Fixes#39897
Change-Id: I8564916055f5fadde3382e41fe8820a1071e5f13
GitHub-Last-Rev: f8f2abe8d4
GitHub-Pull-Request: golang/go#39898
Reviewed-on: https://go-review.googlesource.com/c/go/+/240280
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
reflect.assignTo writes to the target using write barriers. Make sure
that the memory it is writing to is zeroed, so the write barrier does
not read pointers from uninitialized memory.
Fixes#39541
Change-Id: Ia64b2cacc193bffd0c1396bbce1dfb8182d4905b
Reviewed-on: https://go-review.googlesource.com/c/go/+/238760
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently, Value.Addr collapses flagRO, which is a combination of
flagEmbedRO and flagStickyRO, to flagStickyRO. This causes exported
fields of unexported anonymous field from Value.Addr.Elem read only.
This commit fix this by keeping all bits of flagRO from origin
value in Value.Addr. This should be safe due to following reasons:
* Result of Value.Addr is not CanSet because of it is not CanAddr
but not flagRO.
* Addr.Elem get same flagRO as origin, so it should behave same as
origin in CanSet.
Fixes#32772.
Change-Id: I79e086628c0fb6569a50ce63f3b95916f997eda1
GitHub-Last-Rev: 78e280e6d0
GitHub-Pull-Request: golang/go#32787
Reviewed-on: https://go-review.googlesource.com/c/go/+/183937
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The new package "internal/unsafeheader" depends only on "unsafe", and
provides declarations equivalent to reflect.StringHeader and
reflect.SliceHeader but with Data fields of the proper unsafe.Pointer
type (instead of uintptr).
Unlike the types it replaces, the "internal/unsafeheader" package has
a regression test to ensure that its header types remain equivalent to
the declarations provided by the "reflect" package.
Since "internal/unsafeheader" has almost no dependencies, it can be
used in other low-level packages such as "syscall" and "reflect".
This change is based on the corresponding x/sys change in CL 231177.
Fixes#37805
Updates #19367
Change-Id: I7a6d93ef8dd6e235bcab94e7c47270aad047af31
Reviewed-on: https://go-review.googlesource.com/c/go/+/231223
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Allocate the runcases slice on the stack if the number
of select cases is small (up to 4).
Found while looking at production profiles of common
proto based RPC server framework code in Google which do
not have a large number of cases.
name old time/op new time/op delta
Select/1 147ns ± 2% 120ns ± 6% -18.32% (p=0.000 n=7+10)
Select/4 316ns ± 5% 249ns ± 2% -21.23% (p=0.000 n=10+10)
Select/8 516ns ± 3% 515ns ± 3% ~ (p=0.858 n=10+9)
name old alloc/op new alloc/op delta
Select/1 96.0B ± 0% 64.0B ± 0% -33.33% (p=0.000 n=10+10)
Select/4 336B ± 0% 208B ± 0% -38.10% (p=0.000 n=10+10)
Select/8 672B ± 0% 672B ± 0% ~ (all equal)
name old allocs/op new allocs/op delta
Select/1 4.00 ± 0% 3.00 ± 0% -25.00% (p=0.000 n=10+10)
Select/4 7.00 ± 0% 6.00 ± 0% -14.29% (p=0.000 n=10+10)
Select/8 11.0 ± 0% 11.0 ± 0% ~ (all equal)
Change-Id: I1687e74fc8e86606a27f03fa8a561bcfb68775d6
Reviewed-on: https://go-review.googlesource.com/c/go/+/230657
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Given:
type u struct{}
func (u) M() {}
type t struct { u; u2 u }
var v = reflect.ValueOf(t{})
Package reflect allows:
v.Method(0) // v.M
v.Field(0).Method(0) // v.u.M
but panics from:
v.Field(1).Method(0) // v.u2.M
because u2 is not an exported field. However, u is not an exported
field either, so this is inconsistent.
It seems like this behavior originates from #12367, where it was
decided to allow traversing unexported embedded fields to be able to
access their exported fields, since package reflect doesn't provide an
alternative way to access promoted fields directly.
But extending that logic to promoted *methods* was inappropriate,
because package reflect's normal method handling logic already handles
promoted methods correctly. This CL corrects that mistake.
Fixes#38521.
Change-Id: If65008965f35927b4e7927cddf8614695288eb19
Reviewed-on: https://go-review.googlesource.com/c/go/+/228902
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This was accidentally broken in CL 166462, which introduce another
function in the panicking path without adjusting the argument to
runtime.Caller.
Change-Id: Ib6f9ed8673fefd458c7a4e3a918c45c5b31ca552
Reviewed-on: https://go-review.googlesource.com/c/go/+/229082
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Trying this CL again, with a test that skips 387.
When converting from float32->float64->float32, any signal NaNs
get converted to quiet NaNs. Avoid that so using reflect.Value.Convert
between two float32 types keeps the signal bit of NaNs.
Skip the test on 387. I don't see any sane way of ensuring that a
float load + float store is faithful on that platform.
Fixes#36400
Change-Id: Ic316c74ddc155632e40424e207375b5d50dcd853
Reviewed-on: https://go-review.googlesource.com/c/go/+/221792
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Instead use string(r) where r has type rune.
This is in preparation for a vet warning for string(i).
Updates #32479
Change-Id: Ic205269bba1bd41723950219ecfb67ce17a7aa79
Reviewed-on: https://go-review.googlesource.com/c/go/+/220844
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Akhil Indurti <aindurti@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Toshihiro Shiino <shiino.toshihiro@gmail.com>
When converting from float32->float64->float32, any signal NaNs
get converted to quiet NaNs. Avoid that so using reflect.Value.Convert
between two float32 types keeps the signal bit of NaNs.
Update #36400
Change-Id: Ic4dd04c4be7189d2171d12b7e4e8f7cf2fb22bb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/213497
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The runtime implementation of select has an upper limit on the number of
select cases that are supported in order to maintain low stack memory
usage. Rather than support an arbitrary number of select cases, we've
opted to panic early with a useful message pointing the user directly
at the problem.
Fixes#37350
Change-Id: Id129ba281ae120387e681ef96be8adcf89725840
Reviewed-on: https://go-review.googlesource.com/c/go/+/220583
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
R0 is not a thing in riscv64 assembly - use ZERO (rather than X0) since
the rest of this currently uses ABI names.
Updates #27532
Change-Id: I28fb68e9f80d05231a07c5921e7062777234e2c5
Reviewed-on: https://go-review.googlesource.com/c/go/+/215437
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Based on riscv-go port.
Update #27532
Change-Id: I791924f71078fd8dfe9c2fc03a3f21a3bc673721
Reviewed-on: https://go-review.googlesource.com/c/go/+/204634
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
After golang.org/cl/210124, I wondered if the same error had gone
unnoticed elsewhere. I quickly spotted another dozen mistakes after
reading through the output of:
git grep '\<[Aa]n [bcdfgjklmnpqrtvwyz][a-z]'
Many results are false positives for acronyms like "an mtime", since
it's pronounced "an em-time". However, the total amount of output isn't
that large given how simple the grep pattern is.
Change-Id: Iaa2ca69e42f4587a9e3137d6c5ed758887906ca6
Reviewed-on: https://go-review.googlesource.com/c/go/+/210678
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Zach Jones <zachj1@gmail.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Go specification says: A value x is assignable to a variable of type T if x
is a bidirectional channel value, T is a channel type, x's type V and T have
identical element types, and at least one of V or T is not a defined type.
However, the current reflection implementation is incorrect which makes
"x is assignable to T" even if type V and T are both defined type.
The current reflection implementation also mistakes the base types of two
non-defined pointer types share the same underlying type when the two
base types satisfy the above mentioned special channel assignability rule.
Fixes#29469
Change-Id: Ia4b9c4ac47dc8e76a11faef422b2e5c5726b78b3
GitHub-Last-Rev: 487c20a564
GitHub-Pull-Request: golang/go#29739
Reviewed-on: https://go-review.googlesource.com/c/go/+/157822
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The code for generating gcdata was (technically) unsafe. It was also
rather repetitive. This CL refactors it a bit and abstracts use of
gcdata into a helper gcSlice method.
Updates #34972.
Change-Id: Ie86d7822eafe263f1d3d150eedf0ec66be1ec85d
Reviewed-on: https://go-review.googlesource.com/c/go/+/202582
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This CL adds -d=checkptr as a compile-time option for adding
instrumentation to check that Go code is following unsafe.Pointer
safety rules dynamically. In particular, it currently checks two
things:
1. When converting unsafe.Pointer to *T, make sure the resulting
pointer is aligned appropriately for T.
2. When performing pointer arithmetic, if the result points to a Go
heap object, make sure we can find an unsafe.Pointer-typed operand
that pointed into the same object.
These checks are currently disabled for the runtime, and can also be
disabled through a new //go:nocheckptr annotation. The latter is
necessary for functions like strings.noescape, which intentionally
violate safety rules to workaround escape analysis limitations.
Fixes#22218.
Change-Id: If5a51273881d93048f74bcff10a3275c9c91da6a
Reviewed-on: https://go-review.googlesource.com/c/go/+/162237
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Part 1: CL 199499 (GOOS nacl)
Part 2: CL 200077 (amd64p32 files, toolchain)
Part 3: stuff that arguably should've been part of Part 2, but I forgot
one of my grep patterns when splitting the original CL up into
two parts.
This one might also have interesting stuff to resurrect for any future
x32 ABI support.
Updates #30439
Change-Id: I2b4143374a253a003666f3c69e776b7e456bdb9c
Reviewed-on: https://go-review.googlesource.com/c/go/+/200318
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This is part two if the nacl removal. Part 1 was CL 199499.
This CL removes amd64p32 support, which might be useful in the future
if we implement the x32 ABI. It also removes the nacl bits in the
toolchain, and some remaining nacl bits.
Updates #30439
Change-Id: I2475d5bb066d1b474e00e40d95b520e7c2e286e1
Reviewed-on: https://go-review.googlesource.com/c/go/+/200077
Reviewed-by: Ian Lance Taylor <iant@golang.org>
You were a useful port and you've served your purpose.
Thanks for all the play.
A subsequent CL will remove amd64p32 (including assembly files and
toolchain bits) and remaining bits. The amd64p32 removal will be
separated into its own CL in case we want to support the Linux x32 ABI
in the future and want our old amd64p32 support as a starting point.
Updates #30439
Change-Id: Ia3a0c7d49804adc87bf52a4dea7e3d3007f2b1cd
Reviewed-on: https://go-review.googlesource.com/c/go/+/199499
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This was missing from the original StructOf CL because I couldn't
think of a use for it. Now I can: even with types used entirely
by reflect, unexported fields can be set using UnsafeAddr.
Change-Id: I5e7e3d81d16e8817cdd69d85796ce33930ef523b
Reviewed-on: https://go-review.googlesource.com/c/go/+/85661
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently, if you call various reflect methods you might get a panic with a
message like, "reflect: Field of non-struct type". Sometimes it's easy to
grok what's going on, but other times you need to laboriously go perform
reflect.ValueOf(myType).Kind().
This CL just adds that detail to the error message, saving debuggers the
extra step and making the error message more clear.
Change-Id: I7e0c211a3001e6b217b828cbcf50518080b5cb1e
Reviewed-on: https://go-review.googlesource.com/c/go/+/183097
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Before this change, when DeepEqual checks values with cycle, it may
panic due to stack overflow.
Here is a sample to reproduce the issue.
makeCycleMap := func() interface{} {
cycleMap := map[string]interface{}{}
cycleMap["foo"] = cycleMap
return cycleMap
}
m1 := makeCycleMap()
m2 := makeCycleMap()
reflect.DeepEqual(m1, m2) // stack overflow
The root cause is that DeepEqual fails to cache interface values
in visited map, which is used to detect cycle. DeepEqual calls
CanAddr to check whether a value should be cached or not. However,
all values referenced by interface don't have flagAddr thus all these
values are not cached.
THe fix is to remove CanAddr calls and use underlying ptr in value
directly. As ptr is only read-only in DeepEqual for caching, it's
safe to do so. We don't use UnsafeAddr this time, because this method
panics when CanAddr returns false.
Fixes#33907
Change-Id: I2aa88cc060a2c2192b1d34c129c0aad4bd5597e7
Reviewed-on: https://go-review.googlesource.com/c/go/+/191940
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Make it clear that IsValid checks that we have valid
reflect.Value and not the value of `v`
fixes#34152
Change-Id: Ib3d359eeb3a82bf733b9ed17c777fc4c143bc29c
Reviewed-on: https://go-review.googlesource.com/c/go/+/193841
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Right now we generate hash functions for all types, just in case they
are used as map keys. That's a lot of wasted effort and binary size
for types which will never be used as a map key. Instead, generate
hash functions only for types that we know are map keys.
Just doing that is a bit too simple, since maps with an interface type
as a key might have to hash any concrete key type that implements that
interface. So for that case, implement hashing of such types at
runtime (instead of with generated code). It will be slower, but only
for maps with interface types as keys, and maybe only a bit slower as
the aeshash time probably dominates the dispatch time.
Reorg where we keep the equals and hash functions. Move the hash function
from the key type to the map type, saving a field in every non-map type.
That leaves only one function in the alg structure, so get rid of that and
just keep the equal function in the type descriptor itself.
cmd/go now has 10 generated hash functions, instead of 504. Makes
cmd/go 1.0% smaller. Update #6853.
Speed on non-interface keys is unchanged. Speed on interface keys
is ~20% slower:
name old time/op new time/op delta
MapInterfaceString-8 23.0ns ±21% 27.6ns ±14% +20.01% (p=0.002 n=10+10)
MapInterfacePtr-8 19.4ns ±16% 23.7ns ± 7% +22.48% (p=0.000 n=10+8)
Change-Id: I7c2e42292a46b5d4e288aaec4029bdbb01089263
Reviewed-on: https://go-review.googlesource.com/c/go/+/191198
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Some were never used, and some haven't been used for years.
One exception is net/http's readerAndCloser, which was only used in a
test. Move it to a test file.
While at it, remove a check in regexp that could never fire; the field
is an uint32, so it can never be negative.
Change-Id: Ia2200f6afa106bae4034045ea8233b452f38747b
Reviewed-on: https://go-review.googlesource.com/c/go/+/192621
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
directlyAssignable invoked rtype.Name() just to compare its result
to empty string. We really only need to check whether rtype has
name. It can be done much cheaper, by checking tflagNamed.
Benchmark: https://play.golang.org/p/V2BzESPuf2w
name old time/op new time/op delta
DirectlyAssignable-12 32.7ns ± 6% 6.6ns ± 6% -79.80% (p=0.008 n=5+5)
Fixes#32186
Change-Id: I1a2a167dbfddf319fba3015cb6a011bf010f99a8
Reviewed-on: https://go-review.googlesource.com/c/go/+/178518
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
When calling a function obtained from reflect.Value.Method (or
MethodByName), we copy the arguments from the caller frame, which
does not include the receiver, to a new frame to call the actual
method, which does include the receiver. Here we need to align
the first (non-receiver) argument. As the receiver is pointer
sized, it is generally naturally aligned, except on amd64p32,
where the argument can have larger alignment, and this aligning
becomes necessary.
Fixes#33628.
Change-Id: I5bea0e20173f06d1602c5666d4f334e3d0de5c1e
Reviewed-on: https://go-review.googlesource.com/c/go/+/190297
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
There is a subtle distinction between a value
*being* the zero value vs being *equal to* the zero value.
This was discussed at length in #31450.
Using "a zero value" in the docs suggests that there may
be more than zero value. That is possible on the "equal to
zero value" reading, but not the "is zero" reading that we
selected for the semantics of IsZero.
This change attempts to prevent any confusion on this front by
switching to "the zero value" in the documentation.
And while we're here, eliminate a double-space.
(Darn macbook keyboards.)
Change-Id: Iaa02ba297438793f5a90be9919a4d53baef92f8e
Reviewed-on: https://go-review.googlesource.com/c/go/+/182617
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Gccgo's implementation of direct interface types has bugs that
causes reflect Call of method from Type.Method fail. CL 175837
and CL 175798 fix the bug. This CL adds a test.
Change-Id: I4e5f2cb96304c1ac7be04ca6d2851bac52b8eb24
Reviewed-on: https://go-review.googlesource.com/c/go/+/175880
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Most changes are removing redundant declaration of type when direct
instantiating value of map or slice, e.g. []T{T{}} become []T{{}}.
Small changes are removing the high order of subslice if its value
is the length of slice itself, e.g. T[:len(T)] become T[:].
The following file is excluded due to incompatibility with go1.4,
- src/cmd/compile/internal/gc/ssa.go
Change-Id: Id3abb09401795ce1e6da591a89749cba8502fb26
Reviewed-on: https://go-review.googlesource.com/c/go/+/166437
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Before this CL we used to panic with "nil pointer dereference" because
the value we're calling assignTo on is the zero Value. Provide a better
error message.
Fixes#28748
Change-Id: I7dd4c9e30b599863664d91e78cc45878d8b0052e
Reviewed-on: https://go-review.googlesource.com/c/go/+/175440
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Instead of requiring exact type match, allow assignment conversions
(those conversions allowed in the language spec without a cast) on the
returned values.
Particularly useful when the type being returned is an interface type,
but the Value actually returned is a concrete value implementing that
type (as it is tricky to return a Value which has interface type).
RELNOTE=y
Fixes#28761
Change-Id: I69eef07ca51690b2086dfa1eb549db5e4724c657
Reviewed-on: https://go-review.googlesource.com/c/go/+/174531
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The spec carefully and consistently uses "key" and "element"
as map terminology. The implementation, not so much.
This change attempts to make the implementation consistently
hew to the spec's terminology. Beyond consistency, this has
the advantage of avoid some confusion and naming collisions,
since v and value are very generic and commonly used terms.
I believe that I found all everything, but there are a lot of
non-obvious places for these to hide, and grepping for them is hard.
Hopefully this change changes enough of them that we will start using
elem going forward. Any remaining hidden cases can be removed ad hoc
as they are discovered.
The only externally-facing part of this change is in package reflect,
where there is a minor doc change and a function parameter name change.
Updates #27167
Change-Id: I2f2d78f16c360dc39007b9966d5c2046a29d3701
Reviewed-on: https://go-review.googlesource.com/c/go/+/174523
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
A handful of packages were reimplementing IsExported, so use
token.IsExported instead. This caused the deps test to fail for net/rpc.
However, net/rpc deals with Go types, and go/token is light and fairly
low-level in terms of Go tooling packages, so that's okay.
While at it, replace all uses of ast.IsExported with token.IsExported.
This is more consistent, and also means that the import graphs are
leaner. A couple of files no longer need to import go/ast, for example.
We can't get rid of cmd/compile/internal/types.IsExported, as the
compiler can only depend on go/token as of Go 1.4. However, gc used
different implementations in a couple of places, so consolidate the use
of types.IsExported there.
Finally, we can't get rid of the copied IsExported implementation in
encoding/gob, as go/token depends on it as part of a test. That test
can't be an external test either, so there's no easy way to break the
import cycle.
Overall, this removes about forty lines of unnecessary code.
Change-Id: I86a475b7614261e6a7b0b153d5ca02b9f64a7b2d
Reviewed-on: https://go-review.googlesource.com/c/go/+/172037
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>