Commit Graph

525 Commits

Author SHA1 Message Date
Cherry Zhang ef36e4fd0e reflect: keep pointer register results alive in callMethod
When callMethod calls the underlying method, after reflectcall
it gets the result registers in "Ints" slots but not in "Ptrs"
slots. If the GC runs at this point, it may lose track of those
pointers and free the memory they point to.

To make sure the GC sees the pointer results, copy "Ints" to
"Ptrs", and keep them alive until we return to the caller.

This fixes test/fixedbugs/issue27695.go with register ABI.

Change-Id: I4092c91bcbd6954683740a12d91d689900446875
Reviewed-on: https://go-review.googlesource.com/c/go/+/309909
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2021-04-14 16:37:06 +00:00
Ian Lance Taylor 554d2c4f06 reflect: panic on New of go:notinheap type
For #42076
Fixes #45451

Change-Id: I69646226d3480d5403205412ddd13c0cfc2c8a53
Reviewed-on: https://go-review.googlesource.com/c/go/+/308970
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2021-04-09 23:54:31 +00:00
David Chase 912c4e29d3 reflect: fix typo in result-in-registers case
t is the type of the function that was called
tv is the type of the result

This fixes the failures for
GOEXPERIMENT=regabi,regabiargs go test go test text/template
GOEXPERIMENT=regabi,regabiargs go test go test html/template

Updates #40724.

Change-Id: Ic9b02d72d18ff48c9de1209987cc39da619c2241
Reviewed-on: https://go-review.googlesource.com/c/go/+/308189
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2021-04-08 14:23:47 +00:00
Austin Clements b675e52e95 internal/goexperiment: consolidate experiment-enabled constants
Currently, we have boolean and integral constants for GOEXPERIMENTs in
various places. Consolidate these into automatically generated
constants in the internal/goexperiment package.

Change-Id: I42a49aba2a3b4c722fedea23a613162cd8a67bee
Reviewed-on: https://go-review.googlesource.com/c/go/+/307818
Trust: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2021-04-08 02:17:18 +00:00
Michael Anthony Knyszek b084073b53 reflect: refactor funcLayout tests
This change refactors the existing funcLayout tests and sets them up to
support the new register ABI by explicitly setting the register counts
to zero. This allows the test to pass if GOEXPERIMENT=regabiargs is set.

A follow-up change will add tests for a non-zero register count.

For #40724.

Change-Id: Ibbe061b4ed4fd70566eb38b9e6182dca32b81127
Reviewed-on: https://go-review.googlesource.com/c/go/+/307869
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-04-06 22:55:58 +00:00
Cherry Zhang d446cb7cff reflect: call ABI0 callReflect/callMethod
Currently the assembly code marshals arguments in ABI0 layout.
Call the ABI0 functions. We may want to move to ABIInternal at
some point (maybe when register args is always enabled).

Updates #40724.

Change-Id: I23bb3073f3f6420a8d0c119b65ae3e577578aadb
Reviewed-on: https://go-review.googlesource.com/c/go/+/307237
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
2021-04-05 22:43:42 +00:00
Michael Anthony Knyszek 41cf18eda7 reflect: fix methodValueCall frame size on mips64
Fixes a mistake from golang.org/cl/298670.

Change-Id: I2f789f9fe003c856a993f7d462a2e84936743a1a
Reviewed-on: https://go-review.googlesource.com/c/go/+/306930
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-02 19:45:52 +00:00
Michael Anthony Knyszek 34b87b4a1a reflect: remove short-circuits for zero-sized types in ABI algorithm
This change removes two short-circuits for zero-sized types (zero-sized
structs and zero-sized struct fields) in the recursive cases of the ABI
algorithm, because this does not match the spec's algorithm, nor the
compiler's algorithm.

The failing case here is a struct with a field that is an array of
non-zero length but whose element type is zero-sized. This struct must
be stack-assigned because of the array, according to the algorithm.
The reflect package was register-assigning it.

Because there were two short-circuits, this can also appear if a struct
has a field that is a zero-sized struct but contains such an array,
also.

This change adds regression tests for both of these cases.

For #44816.
For #40724.

Change-Id: I956804170962448197a1c9853826e3436fc8b1ea
Reviewed-on: https://go-review.googlesource.com/c/go/+/306929
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-02 19:27:06 +00:00
Michael Anthony Knyszek 28c5fed557 reflect: add register ABI support for makeFuncStub and methodValueCall
This change finishes off functionality register ABI for the reflect
package.

Specifically, it implements a call on a MakeFunc'd value by performing
the reverse process that reflect.Value.Call does, using the same ABI
steps. It implements a call on a method value created by reflect by
translating between the method value's ABI to the method's ABI.

Tests are added for both cases.

For #40724.

Change-Id: I302820b61fc0a8f94c5525a002bc02776aef41af
Reviewed-on: https://go-review.googlesource.com/c/go/+/298670
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-04-02 16:53:18 +00:00
Michael Anthony Knyszek 27d306281c reflect,runtime: assume register ABI with GOEXPERIMENT=regabiargs
This change causes finalizers, reflect calls, and Windows syscall
callbacks to assume the register ABI when GOEXPERIMENT=regabiargs is
set. That is, when all Go functions are using the new ABI by default,
these features should assume the new ABI too.

For #40724.

Change-Id: Ie4ee66b8085b692e1ff675f01134c9a4703ae1b9
Reviewed-on: https://go-review.googlesource.com/c/go/+/306571
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-01 22:35:25 +00:00
Michael Anthony Knyszek 51cd074c59 reflect: undo register count increments on register assignment failure
Currently when register assignment fails we roll back all the abiParts
that were generated in the process. However, the total number of
registers also increases, but does not get rolled back. The result is
a very incorrect register assignment.

For #40724.
For #44816.

Change-Id: I1934ea5f95f7608ff2067166255099dbc9135e8c
Reviewed-on: https://go-review.googlesource.com/c/go/+/306109
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-04-01 22:32:31 +00:00
Ignacio Hagopian 6cadfe2fee reflect: cache IsVariadic calls in Call
These calls are cacheable, so do that to avoid doing extra work.

This opportunity was discovered while taking a look at a CPU profile
while investigating #7818.

I added a BenchmarkCallMethod, which is similar to BechmarkCall but
for a method receiver.

Benchmark results, including the new BenchmarkCallMethod:

	name                       old time/op    new time/op    delta
	Call-16                      22.0ns ±19%    20.2ns ±17%  -8.08%  (p=0.000 n=40+40)
	CallMethod-16                 100ns ± 3%      91ns ± 2%  -9.13%  (p=0.000 n=40+39)
	CallArgCopy/size=128-16      15.7ns ± 1%    14.3ns ± 4%  -8.98%  (p=0.000 n=38+37)
	CallArgCopy/size=256-16      15.9ns ± 3%    15.0ns ± 5%  -6.12%  (p=0.000 n=39+39)
	CallArgCopy/size=1024-16     18.8ns ± 6%    17.1ns ± 6%  -9.03%  (p=0.000 n=38+38)
	CallArgCopy/size=4096-16     26.6ns ± 3%    25.2ns ± 4%  -5.19%  (p=0.000 n=39+40)
	CallArgCopy/size=65536-16     379ns ± 3%     371ns ± 5%  -2.11%  (p=0.000 n=39+40)

	name                       old alloc/op   new alloc/op   delta
	Call-16                       0.00B          0.00B         ~     (all equal)
	CallMethod-16                 0.00B          0.00B         ~     (all equal)

	name                       old allocs/op  new allocs/op  delta
	Call-16                        0.00           0.00         ~     (all equal)
	CallMethod-16                  0.00           0.00         ~     (all equal)

	name                       old speed      new speed      delta
	CallArgCopy/size=128-16    8.13GB/s ± 1%  8.92GB/s ± 4%  +9.77%  (p=0.000 n=38+38)
	CallArgCopy/size=256-16    16.1GB/s ± 3%  17.1GB/s ± 5%  +6.56%  (p=0.000 n=39+39)
	CallArgCopy/size=1024-16   54.6GB/s ± 6%  60.1GB/s ± 5%  +9.93%  (p=0.000 n=38+38)
	CallArgCopy/size=4096-16    154GB/s ± 5%   163GB/s ± 4%  +5.63%  (p=0.000 n=40+40)
	CallArgCopy/size=65536-16   173GB/s ± 3%   177GB/s ± 5%  +2.18%  (p=0.000 n=39+40)

Updates #7818.

Change-Id: I94f88811ea9faf3dc2543984a13b360b5db66a4b
GitHub-Last-Rev: 9bbaa1854a
GitHub-Pull-Request: golang/go#43475
Reviewed-on: https://go-review.googlesource.com/c/go/+/281252
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Daniel Martí <mvdan@mvdan.cc>
Trust: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Go Bot <gobot@golang.org>
2021-03-30 17:41:58 +00:00
Michael Anthony Knyszek bdbba22404 reflect: add tests for reflect.Value.Call for the new ABI
This change adds tests for reflect.Value.Call for calling functions
using the new register-based ABI.

For #40724.

Change-Id: Ia9afd43e26dd80c7e36dd135a5b71acce8074801
Reviewed-on: https://go-review.googlesource.com/c/go/+/299269
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-03-18 21:22:04 +00:00
Paschalis Tsilias d7cc2f1d7c reflect: panic if ArrayOf is called with negative length
Since we cannot change the signature of reflect.ArrayOf to return an
error, we panic instead of producing a wrong result.

Fixes #43603

Change-Id: I23915df8d190f35af4d00ab86768868cd621e839
Reviewed-on: https://go-review.googlesource.com/c/go/+/284136
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-03-15 23:49:28 +00:00
Roger Peppe 009bfeae86 reflect: add VisibleFields function
When writing code that reflects over a struct type, it's a common requirement to know the full set of struct fields, including fields available due to embedding of anonymous members while excluding fields that are erased because they're at the same level as another field with the same name.

The logic to do this is not that complex, but it's a little subtle and easy to get wrong.

This CL adds a new `VisibleFields` function to the reflect package that returns the full set of effective fields that apply in a given struct type.

Performance isn't a prime consideration, as it's common to cache results by type.

Fixes #42782

Change-Id: I7f1af76cecff9b8a2490f17eec058826e396f660
Reviewed-on: https://go-review.googlesource.com/c/go/+/281233
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Daniel Martí <mvdan@mvdan.cc>
2021-03-05 23:47:39 +00:00
Michael Anthony Knyszek a2f7067233 reflect: include the alignment of zero-sized types in stack offsets
This change modifies the reflect ABI assignment algorithm to catch
zero-sized types at the top level of each argument and faux-stack-assign
them. It doesn't actually generate an ABI step, which is unnecessary,
but it ensures that the offsets of further stack-assigned arguments are
aligned to the alignment of that zero-sized argument.

This change is necessary to have the register ABI assignment algorithm
gracefully degrade to ABI0 when no registers are present in the ABI.

Fixes #44377.

Change-Id: Ia95571688a61259302bb3c6d5fb33fbb6b5e8db8
Reviewed-on: https://go-review.googlesource.com/c/go/+/293789
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Trust: Than McIntosh <thanm@google.com>
2021-03-05 15:34:32 +00:00
Michael Anthony Knyszek c5a1c2276e reflect: use global variables for register count
This change switches reflect to use global variables for ABI-related
register counts instead of internal/abi constants. The advantage of
doing so is that we can make the internal/abi constants non-zero and
enable the runtime register argument spiller/unspiller even if they're
not used. It's basically turning two things we need to flip when we
switch to the register ABI into one.

It also paves the way for testing the reflect register ABI path
independently, because now we can switch the global variables at will
and run the register-assignment algorithm in tests without having the
rest of the runtime be broken.

Change-Id: Ie23629a37a5c80aeb24909d4bd9eacbd3f0c06d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/293149
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-03-05 15:34:15 +00:00
John Bampton 580636a78a all: fix spelling
Change-Id: Iad14571c3e19b01740cd744f0b3025b3e2f1cb72
GitHub-Last-Rev: e806401929
GitHub-Pull-Request: golang/go#44685
Reviewed-on: https://go-review.googlesource.com/c/go/+/297409
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-03-02 03:07:33 +00:00
Michael Anthony Knyszek cda8ee095e reflect: fix register ABI spill space calculation
Currently this does things the old way by computing the number of
registers, but we're going to be using their ABI0 layout for the spill
space for now.

Change-Id: Ibcef1ee48fd834af7cbdaabe704bcabe066ed358
Reviewed-on: https://go-review.googlesource.com/c/go/+/293011
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
2021-02-26 20:49:57 +00:00
Joe Tsai b83d073e9e reflect: add Method.IsExported and StructField.IsExported methods
The IsExported method is a more intuitive helper for checking whether
the method or field is exported than checking whether PkgPath is empty.

In the same CL, modify the standard library to make use of this helper.

Fixes #41563

Change-Id: Iaacfb3b74449501f98e2707aa32095a32bd3c3c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/266197
Trust: Joe Tsai <joetsai@digital-static.net>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2021-02-25 21:21:51 +00:00
yangwenmai 7af821a661 all: faster midpoint computation in binary search
On my machine (3.1 GHz Quad-Core Intel Core i7, macOS 10.15.7 10.15.7), go 1.15.6

benchstat:
name          old time/op  new time/op  delta
SearchInts-8  20.3ns ± 1%  16.6ns ± 6%  -18.37%  (p=0.000 n=9+10)

Change-Id: I346e5955fd6df6ce10254b22267dbc8d5a2b16c0
Reviewed-on: https://go-review.googlesource.com/c/go/+/279439
Reviewed-by: Ben Shi <powerman1st@163.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Trust: Robert Griesemer <gri@golang.org>
2021-02-23 01:37:31 +00:00
Michael Anthony Knyszek e0215315f5 [dev.regabi] reflect: support for register ABI on amd64 for reflect.(Value).Call
This change adds support for the new register ABI on amd64 to
reflect.(Value).Call. If internal/abi's register counts are non-zero,
reflect will try to set up arguments in registers on the Call path.

Note that because the register ABI becomes ABI0 with zero registers
available, this should keep working as it did before.

This change does not add any tests for the register ABI case because
there's no way to do so at the moment.

For #40724.

Change-Id: I8aa089a5aa5a31b72e56b3d9388dd3f82203985b
Reviewed-on: https://go-review.googlesource.com/c/go/+/272568
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
2021-02-16 15:51:50 +00:00
Matthew Dempsky 7e0a81d280 [dev.regabi] all: merge master (dab3e5a) into dev.regabi
This merge had two conflicts to resolve:

1. The embed code on master had somewhat substantially diverged, so
this CL tediously backported the changes to dev.regabi. In particular,
I went through all of the embed changes to gc/{embed,noder,syntax}.go
and made sure the analogous code on dev.regabi in noder/noder.go and
staticdata/embed.go mirrors it.

2. The init-cycle reporting code on master was extended slightly to
track already visited declarations to avoid exponential behavior. The
same fix is applied on dev.regabi, just using ir.NameSet instead of
map[ir.Node]bool.

Conflicts:

- src/cmd/compile/internal/gc/embed.go
- src/cmd/compile/internal/gc/noder.go
- src/cmd/compile/internal/gc/syntax.go
- src/cmd/compile/internal/pkginit/initorder.go
- src/embed/internal/embedtest/embed_test.go
- src/go/types/stdlib_test.go

Merge List:

+ 2021-01-22 dab3e5affe runtime: switch runtime to libc for openbsd/amd64
+ 2021-01-22 a1b53d85da cmd/go: add documentation for test and xtest fields output by go list
+ 2021-01-22 b268b60774 runtime: remove pthread_kill/pthread_self for openbsd
+ 2021-01-22 ec4051763d runtime: fix typo in mgcscavenge.go
+ 2021-01-22 7ece3a7b17 net/http: fix flaky TestDisableKeepAliveUpgrade
+ 2021-01-22 50cba0506f time: clarify Timer.Reset behavior on AfterFunc Timers
+ 2021-01-22 cf10e69f17 doc/go1.16: mention net/http.Transport.GetProxyConnectHeader
+ 2021-01-22 ec1b945265 doc/go1.16: mention path/filepath.WalkDir
+ 2021-01-22 11def3d40b doc/go1.16: mention syscall.AllThreadsSyscall
+ 2021-01-21 07b0235609 doc/go1.16: add notes about package-specific fs.FS changes
+ 2021-01-21 e2b4f1fea5 doc/go1.16: minor formatting fix
+ 2021-01-21 9f43a9e07b doc/go1.16: mention new debug/elf constants
+ 2021-01-21 3c2f11ba5b cmd/go: overwrite program name with full path
+ 2021-01-21 953d1feca9 all: introduce and use internal/execabs
+ 2021-01-21 b186e4d70d cmd/go: add test case for cgo CC setting
+ 2021-01-21 5a8a2265fb cmd/cgo: report exec errors a bit more clearly
+ 2021-01-21 46e2e2e9d9 cmd/go: pass resolved CC, GCCGO to cgo
+ 2021-01-21 3d40895e36 runtime: switch openbsd/arm64 to pthreads
+ 2021-01-21 d95ca91380 crypto/elliptic: fix P-224 field reduction
+ 2021-01-20 ecf4ebf100 cmd/internal/moddeps: check content of all modules in GOROOT
+ 2021-01-20 d2d155d1ae runtime: don't adjust timer pp field in timerWaiting status
+ 2021-01-20 803d18fc6c cmd/go: set Incomplete field on go list output if no files match embed
+ 2021-01-20 6e243ce71d cmd/go: have go mod vendor copy embedded files in subdirs
+ 2021-01-20 be28e5abc5 cmd/go: fix mod_get_fallback test
+ 2021-01-20 928bda4f4a runtime: convert openbsd/amd64 locking to libc
+ 2021-01-19 824f2d635c cmd/go: allow go fmt to complete when embedded file is missing
+ 2021-01-19 0575e35e50 cmd/compile: require 'go 1.16' go.mod line for //go:embed
+ 2021-01-19 ccb2e90688 cmd/link: exit before Asmb2 if error
+ 2021-01-19 ca5774a5a5 embed: treat uninitialized FS as empty
+ 2021-01-19 d047c91a6c cmd/link,runtime: switch openbsd/amd64 to pthreads
+ 2021-01-19 61debffd97 runtime: factor out usesLibcall
+ 2021-01-19 9fed39d281 runtime: factor out mStackIsSystemAllocated
+ 2021-01-18 dbab079835 runtime: free Windows event handles after last lock is dropped
+ 2021-01-18 5a8fbb0d2d os: do not close syscall.Stdin in TestReadStdin
+ 2021-01-15 682a1d2176 runtime: detect errors in DuplicateHandle
+ 2021-01-15 9f83418b83 cmd/link: remove GOROOT write in TestBuildForTvOS
+ 2021-01-15 ec9470162f cmd/compile: allow embed into any string or byte slice type
+ 2021-01-15 54198b04db cmd/compile: disallow embed of var inside func
+ 2021-01-15 b386c735e7 cmd/go: fix go generate docs
+ 2021-01-15 bb5075a525 syscall: remove RtlGenRandom and move it into internal/syscall
+ 2021-01-15 1deae0b597 os: invoke processKiller synchronously in testKillProcess
+ 2021-01-15 ff196c3e84 crypto/x509: update iOS bundled roots to version 55188.40.9
+ 2021-01-14 e125ccd10e cmd/go: in 'go mod edit', validate versions given to -retract and -exclude
+ 2021-01-14 eb330020dc cmd/dist, cmd/go: pass -arch for C compilation on Darwin
+ 2021-01-14 84e8a06f62 cmd/cgo: remove unnecessary space in cgo export header
+ 2021-01-14 0c86b999c3 cmd/test2json: document passing -test.paniconexit0
+ 2021-01-14 9135795891 cmd/go/internal/load: report positions for embed errors
+ 2021-01-14 d9b79e53bb cmd/compile: fix wrong complement for arm64 floating-point comparisons
+ 2021-01-14 c73232d08f cmd/go/internal/load: refactor setErrorPos to PackageError.setPos
+ 2021-01-14 6aa28d3e06 go/build: report positions for go:embed directives
+ 2021-01-13 7eb31d999c cmd/go: add hints to more missing sum error messages
+ 2021-01-12 ba76567bc2 cmd/go/internal/modload: delete unused *mvsReqs.next method
+ 2021-01-12 665def2c11 encoding/asn1: document unmarshaling behavior for IMPLICIT string fields
+ 2021-01-11 81ea89adf3 cmd/go: fix non-script staleness checks interacting badly with GOFLAGS
+ 2021-01-11 759309029f doc: update editors.html for Go 1.16
+ 2021-01-11 c3b4c7093a cmd/internal/objfile: don't require runtime.symtab symbol for XCOFF
+ 2021-01-08 59bfc18e34 cmd/go: add hint to read 'go help vcs' to GOVCS errors
+ 2021-01-08 cd6f3a54e4 cmd/go: revise 'go help' documentation for modules
+ 2021-01-08 6192b98751 cmd/go: make hints in error messages more consistent
+ 2021-01-08 25886cf4bd cmd/go: preserve sums for indirect deps fetched by 'go mod download'
+ 2021-01-08 6250833911 runtime/metrics: mark histogram metrics as cumulative
+ 2021-01-08 8f6a9acbb3 runtime/metrics: remove unused StopTheWorld Description field
+ 2021-01-08 6598c65646 cmd/compile: fix exponential-time init-cycle reporting
+ 2021-01-08 fefad1dc85 test: fix timeout code for invoking compiler
+ 2021-01-08 6728118e0a cmd/go: pass signals forward during "go tool"
+ 2021-01-08 e65c543f3c go/build/constraint: add parser for build tag constraint expressions
+ 2021-01-08 0c5afc4fb7 testing/fstest,os: clarify racy behavior of TestFS
+ 2021-01-08 32afcc9436 runtime/metrics: change unit on *-by-size metrics to match bucket unit
+ 2021-01-08 c6513bca5a io/fs: minor corrections to Glob doc
+ 2021-01-08 304f769ffc cmd/compile: don't short-circuit copies whose source is volatile
+ 2021-01-08 ae97717133 runtime,runtime/metrics: use explicit histogram boundaries
+ 2021-01-08 a9ccd2d795 go/build: skip string literal while findEmbed
+ 2021-01-08 d92f8add32 archive/tar: fix typo in comment
+ 2021-01-08 cab1202183 cmd/link: accept extra blocks in TestFallocate
+ 2021-01-08 ee4d32249b io/fs: minor corrections to Glob release date
+ 2021-01-08 54bd1ccce2 cmd: update to latest golang.org/x/tools
+ 2021-01-07 9ec21a8f34 Revert "reflect: support multiple keys in struct tags"
+ 2021-01-07 091414b5b7 io/fs: correct WalkDirFunc documentation
+ 2021-01-07 9b55088d6b doc/go1.16: add release note for disallowing non-ASCII import paths
+ 2021-01-07 fa90aaca7d cmd/compile: fix late expand_calls leaf type for OpStructSelect/OpArraySelect
+ 2021-01-07 7cee66d4cb cmd/go: add documentation for Embed fields in go list output
+ 2021-01-07 e60cffa4ca html/template: attach functions to namespace
+ 2021-01-07 6da2d3b7d7 cmd/link: fix typo in asm.go
+ 2021-01-07 df81a15819 runtime: check mips64 VDSO clock_gettime return code
+ 2021-01-06 4787e906cf crypto/x509: rollback new CertificateRequest fields
+ 2021-01-06 c9658bee93 cmd/go: make module suggestion more friendly
+ 2021-01-06 4c668b25c6 runtime/metrics: fix panic message for Float64Histogram
+ 2021-01-06 d2131704a6 net/http/httputil: fix deadlock in DumpRequestOut
+ 2021-01-05 3e1e13ce6d cmd/go: set cfg.BuildMod to "readonly" by default with no module root
+ 2021-01-05 0b0d004983 cmd/go: pass embedcfg to gccgo if supported
+ 2021-01-05 1b85e7c057 cmd/go: don't scan gccgo standard library packages for imports
+ 2021-01-05 6b37b15d95 runtime: don't take allglock in tracebackothers
+ 2021-01-04 9eef49cfa6 math/rand: fix typo in comment
+ 2021-01-04 b01fb2af9e testing/fstest: fix typo in error message
+ 2021-01-01 3dd5867605 doc: 2021 is the Year of the Gopher
+ 2020-12-31 95ce805d14 io/fs: remove darwin/arm64 special condition
+ 2020-12-30 20d0991b86 lib/time, time/tzdata: update tzdata to 2020f
+ 2020-12-30 ed301733bb misc/cgo/testcarchive: remove special flags for Darwin/ARM
+ 2020-12-30 0ae2e032f2 misc/cgo/test: enable TestCrossPackageTests on darwin/arm64
+ 2020-12-29 780b4de16b misc/ios: fix wording for command line instructions
+ 2020-12-29 b4a71c95d2 doc/go1.16: reference misc/ios/README for how to build iOS programs
+ 2020-12-29 f83e0f6616 misc/ios: add to README how to build ios executables
+ 2020-12-28 4fd9455882 io/fs: fix typo in comment

Change-Id: I2f257bbc5fbb05f15c2d959f8cfe0ce13b083538
2021-01-22 12:01:13 -08:00
Dan Scales a956a0e909 [dev.regabi] cmd/compile, runtime: fix up comments/error messages from recent renames
Went in a semi-automated way through the clearest renames of functions,
and updated comments and error messages where it made sense.

Change-Id: Ied8e152b562b705da7f52f715991a77dab60da35
Reviewed-on: https://go-review.googlesource.com/c/go/+/284216
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2021-01-16 02:31:08 +00:00
Ian Lance Taylor 9ec21a8f34 Revert "reflect: support multiple keys in struct tags"
Proposal #40281 was initially accepted, but has now been declined.
This CL removes most of the work done to implement it.

Specifically this reverts CLs 248341, 274448, 274474, and 278392.

For #40281
For #43226

Change-Id: I5a9ebb4d9cb5fb0962434b64c59beb8343030be5
Reviewed-on: https://go-review.googlesource.com/c/go/+/281515
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
2021-01-07 23:43:25 +00:00
Ian Lance Taylor 9b8c272558 reflect: document multiple keys in struct tags
For #40281
Fixes #42959

Change-Id: Ibc4769fda1592a1373ec720ea30baf319c0a0136
Reviewed-on: https://go-review.googlesource.com/c/go/+/274448
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
2020-12-07 22:16:21 +00:00
Robert Griesemer f0ff6d4a67 reflect: fix Value.Convert for int-to-string conversions (regression)
The bug was introduced by https://golang.org/cl/220844.

Updates #42792.
Fixes #42835.

Change-Id: I03065c7526488aded35ef2f800b7162e1606877a
Reviewed-on: https://go-review.googlesource.com/c/go/+/273326
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-11-26 05:00:21 +00:00
Cuong Manh Le ebc1b8ef28 reflect: update NumMethod doc for interface type
Updates #42123

Change-Id: Ieb43b65c88d15b2475b6f3dd9672c44e7831cc34
Reviewed-on: https://go-review.googlesource.com/c/go/+/264357
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: Russ Cox <rsc@golang.org>
2020-11-03 00:50:57 +00:00
Than McIntosh a313eec386 reflect,runtime: use internal ABI for selected ASM routines, attempt 2
[This is a roll-forward of CL 262319, with a fix for some Darwin test
failures].

Change the definitions of selected runtime assembly routines
from ABI0 (the default) to ABIInternal. The ABIInternal def is
intended to indicate that these functions don't follow the existing Go
runtime ABI. In addition, convert the assembly reference to
runtime.main (from runtime.mainPC) to ABIInternal. Finally, for
functions such as "runtime.duffzero" that are called directly from
generated code, make sure that the compiler looks up the correct
ABI version.

This is intended to support the register abi work, however these
changes should not have any issues even when GOEXPERIMENT=regabi is
not in effect.

Updates #27539, #40724.

Change-Id: Idf507f1c06176073563845239e1a54dad51a9ea9
Reviewed-on: https://go-review.googlesource.com/c/go/+/266638
Trust: Than McIntosh <thanm@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2020-10-30 17:41:35 +00:00
Than McIntosh ddc7e1d16f Revert "reflect,runtime: use internal ABI for selected ASM routines"
This reverts commit 50af50d136.

Reason for revert: Causes failures in the runtime package test on Darwin, apparently.

Change-Id: I006bc1b3443fa7207e92fb4a93e3fb438d4d3de3
Reviewed-on: https://go-review.googlesource.com/c/go/+/266257
Trust: Than McIntosh <thanm@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-10-29 15:58:40 +00:00
Than McIntosh 50af50d136 reflect,runtime: use internal ABI for selected ASM routines
Change the definitions of selected runtime assembly routines
from ABI0 (the default) to ABIInternal. The ABIInternal def is
intended to indicate that these functions don't follow the existing Go
runtime ABI. In addition, convert the assembly reference to
runtime.main (from runtime.mainPC) to ABIInternal. Finally, for
functions such as "runtime.duffzero" that are called directly from
generated code, make sure that the compiler looks up the correct
ABI version.

This is intended to support the register abi work, however these
changes should not have any issues even when GOEXPERIMENT=regabi is
not in effect.

Updates #27539, #40724.

Change-Id: I9846f8dcaccc95718cf2e61a18b7e924a0677e4c
Reviewed-on: https://go-review.googlesource.com/c/go/+/262319
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-10-29 15:13:09 +00:00
Cuong Manh Le 642329fdd5 Revert "cmd/compile: split exported/non-exported methods for interface type"
This reverts commit 8f26b57f9a.

Reason for revert: break a bunch of code, include standard library.

Fixes #42123

Change-Id: Ife90ecbafd2cb395623d1db555fbfc9c1b0098e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/264026
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: Russ Cox <rsc@golang.org>
2020-10-28 17:10:08 +00:00
Keith Randall 009d714098 cmd/compile, runtime: store pointers to go:notinheap types indirectly
pointers to go:notinheap types should be treated as scalars. That
means they shouldn't be stored directly in interfaces, or directly
in reflect.Value.ptr.

Also be sure to use uintpr to compare such pointers in reflect.DeepEqual.

Fixes #42076

Change-Id: I53735f6d434e9c3108d4940bd1bae14c61ef2a74
Reviewed-on: https://go-review.googlesource.com/c/go/+/264480
Trust: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-27 21:29:13 +00:00
Cuong Manh Le 8f26b57f9a cmd/compile: split exported/non-exported methods for interface type
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>
2020-10-09 02:14:32 +00:00
Alexey Vilenskiy 5d12434eee reflect: support multiple keys in struct tags
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>
2020-10-06 00:34:55 +00:00
Keith Randall fe2cfb74ba all: drop 387 support
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>
2020-10-02 00:00:51 +00:00
Ian Lance Taylor 41df0e2218 reflect: add test for variadic reflect.Type.Method
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>
2020-10-01 22:23:53 +00:00
Keith Randall 8925290cf7 reflect: use zero buffer to back the Value returned by Zero
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>
2020-09-18 21:47:28 +00:00
Matthew Dempsky fe23ba4a14 runtime: eliminate scase.kind field
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>
2020-08-18 20:06:33 +00:00
Keith Randall 77a11c05d6 reflect: remove depth from deepequal recursion
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>
2020-08-17 22:05:16 +00:00
Austin Clements d19fedd180 runtime: move checkmarks to a separate bitmap
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>
2020-08-17 14:31:20 +00:00
Alexander Klauer 407bf0ca67 reflect: add parentheses to properly bind <- in ChanOf’s string
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>
2020-08-14 22:58:36 +00:00
Keith Randall 3dec253783 reflect: zero stack slots before writing to them with write barriers
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>
2020-06-19 02:11:35 +00:00
Ian Lance Taylor d872bbcfec reflect: handling flagIndir in DeepEqual potential cycles
Fixes #39607

Change-Id: Ia7e597e0da8a193a25382cc633a1c6080b4f7cbf
Reviewed-on: https://go-review.googlesource.com/c/go/+/238361
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2020-06-18 01:14:19 +00:00
Kezhu Wang 4c003f6b78 reflect: keep RO flags unchanged in Value.Addr
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>
2020-05-04 18:16:49 +00:00
Bryan C. Mills da382a3978 internal/unsafeheader: consolidate stringHeader and sliceHeader declarations into an internal package
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>
2020-05-01 02:31:29 +00:00
Martin Möhrmann 17d5cef257 reflect: reduce allocations for Select with up to 4 cases
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>
2020-04-28 21:08:32 +00:00
Koichi Shiraishi 24a1c8f605 reflect: fix typo on resolveReflectName function documentation
Change-Id: I250de9db4e8aca6e1069d05c73051571f1712091
Reviewed-on: https://go-review.googlesource.com/c/go/+/229141
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2020-04-22 02:44:15 +00:00
Matthew Dempsky 0eb694e9c2 reflect: disallow invoking methods on unexported embedded fields
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>
2020-04-21 05:41:33 +00:00
Ian Lance Taylor f6b30e53bb reflect: return user-visible method name in panic string
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>
2020-04-21 04:14:15 +00:00
Keith Randall 7ffbea9fd8 reflect: when Converting between float32s, don't lose signal NaNs
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>
2020-04-01 16:41:14 +00:00
Ian Lance Taylor 6052838bc3 all: avoid string(i) where i has type int
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>
2020-02-26 04:38:19 +00:00
Keith Randall 0d6b317ee6 Revert "reflect: when Converting between float32s, don't lose signal NaNs"
This reverts commit 7485050c0f.

Reason for revert: Breaking some builders (387, mips, mips64)

Change-Id: I33e5125b7a9a96b55bc5e71880fca4ee30d226a7
Reviewed-on: https://go-review.googlesource.com/c/go/+/220695
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-02-25 06:22:21 +00:00
Keith Randall 7485050c0f reflect: when Converting between float32s, don't lose signal NaNs
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>
2020-02-25 02:50:24 +00:00
Milan Patel 7802b55176 reflect: update Select to panic early on excessive input cases
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>
2020-02-24 16:34:27 +00:00
Joel Sing 02816a2cad reflect: correct riscv64 assembly
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>
2020-01-19 15:28:32 +00:00
Joel Sing 91d75f4e4c reflect: add support for riscv64
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>
2020-01-18 13:45:50 +00:00
Ian Lance Taylor ba66797392 reflect: record PkgPath of StructOf arguments
Fixes #36190
Fixes #36191

Change-Id: I1213ef37b6595af63dbe202a8ade65741caf1356
Reviewed-on: https://go-review.googlesource.com/c/go/+/212001
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-12-19 05:39:31 +00:00
Daniel Martí 41348081fa all: fix a number of misuses of the word "an"
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>
2019-12-10 16:23:10 +00:00
two 95be9b7559 reflect: remove obsolete comment about gobitVector
Change-Id: Ie3495a51ac2021a55e7c1ee43a66d07a5bf2757a
GitHub-Last-Rev: b6a6bab3ab
GitHub-Pull-Request: golang/go#35709
Reviewed-on: https://go-review.googlesource.com/c/go/+/207853
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-11-22 04:26:34 +00:00
go101 4e8d27068d reflect: factor out special channel assignability rule from haveIdenticalUnderlyingType
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>
2019-11-15 15:17:08 +00:00
Matthew Dempsky 5eec0a91ea reflect: fix unsafe conversions reported by -d=checkptr
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>
2019-10-22 18:09:15 +00:00
Matthew Dempsky 9989221ac1 reflect, internal/reflectlite: set capacity when slicing unsafe pointers
Follow the idiom for allowing -d=checkptr to recognize and verify
correctness.

Updates #22218.
Updates #34972.

Change-Id: Ib6001c6f0e6dc535a36bcfaa1ae48e29e0c737f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/202580
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-10-21 23:16:36 +00:00
Matthew Dempsky 80a6fedea0 cmd/compile: add -d=checkptr to validate unsafe.Pointer rules
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>
2019-10-17 00:40:21 +00:00
Brad Fitzpatrick 03ef105dae all: remove nacl (part 3, more amd64p32)
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>
2019-10-10 22:38:38 +00:00
Brad Fitzpatrick 07b4abd62e all: remove the nacl port (part 2, amd64p32 + toolchain)
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>
2019-10-09 22:34:34 +00:00
Brad Fitzpatrick a38a917aee all: remove the nacl port (part 1)
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>
2019-10-09 06:14:44 +00:00
David Crawshaw 2d1c033259 reflect: let StructOf define unexported fields
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>
2019-09-28 00:19:19 +00:00
Jean de Klerk 09824ccfe5 reflect: give type hints in error messages
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>
2019-09-18 20:18:01 +00:00
Huan Du 4dc11ae26b reflect: fix panic in DeepEqual when checking a cycle
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>
2019-09-11 00:56:01 +00:00
Marko Kungla a5026af57c reflect: enhance docs for IsZero and IsValid
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>
2019-09-11 00:16:10 +00:00
Keith Randall 36f30ba289 cmd/compile,runtime: generate hash functions only for types which are map keys
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>
2019-09-03 20:41:29 +00:00
Daniel Martí 03ac39ce5e std: remove unused bits of code all over the place
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>
2019-09-02 12:57:37 +00:00
Sergei Zagurskii 8057c0887f reflect: optimize directlyAssignable to avoid rtype.Name call
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>
2019-08-27 16:44:22 +00:00
Cherry Zhang 5f45a3337e reflect: align first argument in callMethod
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>
2019-08-14 19:49:15 +00:00
Josh Bleecher Snyder 52572afa20 reflect,doc: use "the" instead of "a" in IsZero docs
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>
2019-06-18 15:08:08 +00:00
Cherry Zhang 2d32d3675a reflect: add a test for Calling a Method of a direct interface type
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>
2019-05-08 13:56:52 +00:00
Shulhan ed7f323c8f all: simplify code using "gofmt -s -w"
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>
2019-05-06 22:19:22 +00:00
Keith Randall 04845fe78a reflect: special-case panic message when returning Value{} from MakeFunc function
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>
2019-05-06 21:23:29 +00:00
Keith Randall fe83731651 reflect: MakeFunc: allow assignment conversions on values returned from the wrapped function
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>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-05-02 22:17:31 +00:00
Josh Bleecher Snyder 73cb9a1cb3 all: refer to map elements as elements instead of values
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>
2019-04-30 18:18:12 +00:00
Daniel Martí 9b968df177 all: clean up code with token.IsExported
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>
2019-04-16 14:43:48 +00:00
Romain Baugue c40bffd905 reflect: add Value.IsZero
Fixes #7501

Change-Id: Iac7c79cd4b30a90b14ed84bf1eba758972232a6c
Reviewed-on: https://go-review.googlesource.com/c/go/+/171337
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-04-13 00:04:07 +00:00
Romain Baugue f33b67b870 reflect: document that method sets are lexicographically sorted
Fixes #30688

Change-Id: I8b63feba4b18bc07a09f6fbfaa33c1b3326b40e6
Reviewed-on: https://go-review.googlesource.com/c/go/+/169597
Reviewed-by: Rob Pike <r@golang.org>
2019-04-03 19:00:48 +00:00
Keith Randall b7b7b4d6d4 reflect: initialize ptrdata earlier in StructOf
It needs to be set before addTypeBits is called.

Fixes #31043

Change-Id: I692b4047dc17bd68202d45da41dd55d432383e59
Reviewed-on: https://go-review.googlesource.com/c/go/+/169318
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-26 03:54:07 +00:00
Keith Randall 17f888c5a8 reflect: fix typeptrdata
We can't use ptrdata inside of typeptrdata, because it won't be
properly initialized until typeptrdata returns.

Fixes #31039

Change-Id: Ib8c89191a7e4cce678a05d351bb6ded81ba23aae
Reviewed-on: https://go-review.googlesource.com/c/go/+/169317
Run-TryBot: Keith Randall <khr@golang.org>
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Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2019-03-26 03:33:13 +00:00
Keith Randall db16de9203 runtime: remove kindNoPointers
We already have the ptrdata field in a type, which encodes exactly
the same information that kindNoPointers does.

My problem with kindNoPointers is that it often leads to
double-negative code like:

   t.kind & kindNoPointers != 0

Much clearer is:

   t.ptrdata == 0

Update #27167

Change-Id: I92307d7f018a6bbe3daca4a4abb4225e359349b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/169157
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-25 20:46:35 +00:00
Daniel Martí 788e038e5d reflect: make all flag.mustBe* methods inlinable
mustBe was barely over budget, so manually inlining the first flag.kind
call is enough. Add a TODO to reverse that in the future, once the
compiler gets better.

mustBeExported and mustBeAssignable were over budget by a larger amount,
so add slow path functions instead. This is the same strategy used in
the sync package for common methods like Once.Do, for example.

Lots of exported reflect.Value methods call these assert-like unexported
methods, so avoiding the function call overhead in the common case does
shave off a percent from most exported APIs.

Finally, add the methods to TestIntendedInlining.

While at it, replace a couple of uses of the 0 Kind with its descriptive
name, Invalid.

name     old time/op    new time/op    delta
Call-8     68.0ns ± 1%    66.8ns ± 1%  -1.81%  (p=0.000 n=10+9)
PtrTo-8    8.00ns ± 2%    7.83ns ± 0%  -2.19%  (p=0.000 n=10+9)

Updates #7818.

Change-Id: Ic1603b640519393f6b50dd91ec3767753eb9e761
Reviewed-on: https://go-review.googlesource.com/c/go/+/166462
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-09 19:50:24 +00:00
Daniel Martí 49662bc6b0 all: simplify multiple for loops
If a for loop has a simple condition and begins with a simple
"if x { break; }"; we can simply add "!x" to the loop's condition.

While at it, simplify a few assignments to use the common pattern
"x := staticDefault; if cond { x = otherValue(); }".

Finally, simplify a couple of var declarations.

Change-Id: I413982c6abd32905adc85a9a666cb3819139c19f
Reviewed-on: https://go-review.googlesource.com/c/go/+/165342
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2019-03-08 14:29:19 +00:00
Keith Randall 9dc3b8b722 reflect: fix more issues with StructOf GC programs
First the insidious bug:

  var n uintptr
  for n := elemPtrs; n > 120; n -= 120 {
    prog = append(prog, 120)
    prog = append(prog, mask[:15]...)
    mask = mask[15:]
  }
  prog = append(prog, byte(n))
  prog = append(prog, mask[:(n+7)/8]...)

The := breaks this code, because the n after the loop is always 0!

We also do need to handle field padding correctly. In particular
the old padding code doesn't correctly handle fields that are not
a multiple of a pointer in size.

Fixes #30606.

Change-Id: Ifcab9494dc25c20116753c5d7e0145d6c2053ed8
Reviewed-on: https://go-review.googlesource.com/c/go/+/165860
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-07 00:06:12 +00:00
Keith Randall 05b3db24c1 reflect: fix StructOf GC programs
They are missing a stop byte at the end.

Normally this doesn't matter, but when including a GC program
in another GC program, we strip the last byte. If that last byte
wasn't a stop byte, then we've thrown away part of the program
we actually need.

Fixes #30606

Change-Id: Ie9604beeb84f7f9442e77d31fe64c374ca132cce
Reviewed-on: https://go-review.googlesource.com/c/go/+/165857
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-06 20:22:14 +00:00
Richard Musiol c0d82bb0ec all: rename WebAssembly instructions according to spec changes
The names of some instructions have been updated in the WebAssembly
specification to be more consistent, see
994591e51c.
This change to the spec is possible because it is still in a draft
state.

Go's support for WebAssembly is still experimental and thus excempt from
the compatibility promise. Being consistent with the spec should
warrant this breaking change to the assembly instruction names.

Change-Id: Iafb8b18ee7f55dd0e23c6c7824aa1fad43117ef1
Reviewed-on: https://go-review.googlesource.com/c/153797
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2019-03-03 21:10:01 +00:00
Cherry Zhang 7e987b7b33 reflect: eliminate write barrier for copying result in callReflect
We are copying the results to uninitialized stack space. Write
barrier is not needed.

Fixes #30041.

Change-Id: Ia91d74dbafd96dc2bd92de0cb479808991dda03e
Reviewed-on: https://go-review.googlesource.com/c/160737
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2019-02-01 19:23:02 +00:00
Keith Randall ed15e82413 runtime: panic on uncomparable map key, even if map is empty
Reorg map flags a bit so we don't need any extra space for the extra flag.

Fixes #23734

Change-Id: I436812156240ae90de53d0943fe1aabf3ea37417
Reviewed-on: https://go-review.googlesource.com/c/155918
Run-TryBot: Keith Randall <khr@golang.org>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-12-29 01:00:54 +00:00
Andrew Bonventre 3b66c00857 reflect: fix panic when Value.IsNil is called for UnsafePointer
UnsafePointer is a valid type kind to call IsNil on.

Fixes #29381

Change-Id: Iaf65d582c67f4be52cd1885badf40f174920500b
Reviewed-on: https://go-review.googlesource.com/c/155797
Run-TryBot: Andrew Bonventre <andybons@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-12-24 01:23:25 +00:00
Vladimir Kovpak 9ffd5f31dc reflect: add comment for String method of Kind struct
On reflect documentation page only this function
doesn't have description, this commit add simple description.

Change-Id: Idcda89ddd1f6fdd1938c4030e89ebdc186255ce6
GitHub-Last-Rev: 1553b834bb
GitHub-Pull-Request: golang/go#28818
Reviewed-on: https://go-review.googlesource.com/c/149721
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-11-16 14:29:14 +00:00
Austin Clements 4f3604d3f2 runtime, reflect: access runtime.reflectcall directly
Currently, package runtime contains the definition of reflect.call,
even though it's just a jump to runtime.reflectcall. This "push"
symbol is confusing, since it's not clear where the definition of
reflect.call comes from when you're in the reflect package.

Replace this with a "pull" symbol: the runtime now defines only
runtime.reflectcall and package reflect uses a go:linkname to access
this symbol directly. This makes it clear where reflect.call is coming
from without any spooky action at a distance and eliminates all of the
definitions of reflect.call in the runtime.

Change-Id: I3ec73cd394efe9df8d3061a57c73aece2e7048dd
Reviewed-on: https://go-review.googlesource.com/c/148657
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-11-12 20:27:14 +00:00
Raghavendra Nagaraj 0e4a0b93d2 reflect: fix StructOf panics from too many methods in embedded fields
Previously we panicked if the number of methods present for an embedded
field was >= 32. This change removes that limit and now StructOf
dynamically calls itself to create space for the number of methods.

Fixes #25402

Change-Id: I3b1deb119796d25f7e6eee1cdb126327b49a0b5e
GitHub-Last-Rev: 16da71ad6b
GitHub-Pull-Request: golang/go#26865
Reviewed-on: https://go-review.googlesource.com/c/128479
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-11-06 13:52:29 +00:00
Brad Fitzpatrick 3813edf26e all: use "reports whether" consistently in the few places that didn't
Go documentation style for boolean funcs is to say:

    // Foo reports whether ...
    func Foo() bool

(rather than "returns true if")

This CL also replaces 4 uses of "iff" with the same "reports whether"
wording, which doesn't lose any meaning, and will prevent people from
sending typo fixes when they don't realize it's "if and only if". In
the past I think we've had the typo CLs updated to just say "reports
whether". So do them all at once.

(Inspired by the addition of another "returns true if" in CL 146938
in fd_plan9.go)

Created with:

$ perl -i -npe 's/returns true if/reports whether/' $(git grep -l "returns true iff" | grep -v vendor)
$ perl -i -npe 's/returns true if/reports whether/' $(git grep -l "returns true if" | grep -v vendor)

Change-Id: Ided502237f5ab0d25cb625dbab12529c361a8b9f
Reviewed-on: https://go-review.googlesource.com/c/147037
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-11-02 22:47:58 +00:00
Don Byington d16e4d34fc reflect: add an example for Kind
Fixes #27990

Change-Id: I0f09fc6f68cec770b1c26eed2315afbf6bf6cd4d
GitHub-Last-Rev: 8486e6d501
GitHub-Pull-Request: golang/go#27991
Reviewed-on: https://go-review.googlesource.com/c/139417
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-03 22:38:53 +00:00
Keith Randall cbafcc55e8 cmd/compile,runtime: implement stack objects
Rework how the compiler+runtime handles stack-allocated variables
whose address is taken.

Direct references to such variables work as before. References through
pointers, however, use a new mechanism. The new mechanism is more
precise than the old "ambiguously live" mechanism. It computes liveness
at runtime based on the actual references among objects on the stack.

Each function records all of its address-taken objects in a FUNCDATA.
These are called "stack objects". The runtime then uses that
information while scanning a stack to find all of the stack objects on
a stack. It then does a mark phase on the stack objects, using all the
pointers found on the stack (and ancillary structures, like defer
records) as the root set. Only stack objects which are found to be
live during this mark phase will be scanned and thus retain any heap
objects they point to.

A subsequent CL will remove all the "ambiguously live" logic from
the compiler, so that the stack object tracing will be required.
For this CL, the stack tracing is all redundant with the current
ambiguously live logic.

Update #22350

Change-Id: Ide19f1f71a5b6ec8c4d54f8f66f0e9a98344772f
Reviewed-on: https://go-review.googlesource.com/c/134155
Reviewed-by: Austin Clements <austin@google.com>
2018-10-03 19:52:49 +00:00
Keith Randall 0b994a9037 reflect: fix s390x reflect method calls
R0 isn't the zero register any more. Oops.

Update #27695.

Change-Id: I46a975ed37d5e570afe2e228d3edf74949e08ad7
Reviewed-on: https://go-review.googlesource.com/138580
Reviewed-by: Michael Munday <mike.munday@ibm.com>
2018-09-30 20:30:55 +00:00
Keith Randall ef50373983 reflect: ensure correct scanning of return values
During a call to a reflect-generated function or method (via
makeFuncStub or methodValueCall), when should we scan the return
values?

When we're starting a reflect call, the space on the stack for the
return values is not initialized yet, as it contains whatever junk was
on the stack of the caller at the time. The return space must not be
scanned during a GC.

When we're finishing a reflect call, the return values are
initialized, and must be scanned during a GC to make sure that any
pointers in the return values are found and their referents retained.

When the GC stack walk comes across a reflect call in progress on the
stack, it needs to know whether to scan the results or not. It doesn't
know the progress of the reflect call, so it can't decide by
itself. The reflect package needs to tell it.

This CL adds another slot in the frame of makeFuncStub and
methodValueCall so we can put a boolean in there which tells the
runtime whether to scan the results or not.

This CL also adds the args length to reflectMethodValue so the
runtime can restrict its scanning to only the args section (not the
results) if the reflect package says the results aren't ready yet.

Do a delicate dance in the reflect package to set the "results are
valid" bit. We need to make sure we set the bit only after we've
copied the results back to the stack. But we must set the bit before
we drop reflect's copy of the results. Otherwise, we might have a
state where (temporarily) no one has a live copy of the results.
That's the state we were observing in issue #27695 before this CL.

The bitmap used by the runtime currently contains only the args.
(Actually, it contains all the bits, but the size is set so we use
only the args portion.) This is safe for early in a reflect call, but
unsafe late in a reflect call. The test issue27695.go demonstrates
this unsafety. We change the bitmap to always include both args
and results, and decide at runtime which portion to use.

issue27695.go only has a test for method calls. Function calls were ok
because there wasn't a safepoint between when reflect dropped its copy
of the return values and when the caller is resumed. This may change
when we introduce safepoints everywhere.

This truncate-to-only-the-args was part of CL 9888 (in 2015). That
part of the CL fixed the problem demonstrated in issue27695b.go but
introduced the problem demonstrated in issue27695.go.

TODO, in another CL: simplify FuncLayout and its test. stack return
value is now identical to frametype.ptrdata + frametype.gcdata.

Fixes #27695

Change-Id: I2d49b34e34a82c6328b34f02610587a291b25c5f
Reviewed-on: https://go-review.googlesource.com/137440
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-09-29 20:25:24 +00:00
Keith Randall e35a41261b reflect: use correct write barrier operations for method funcs
Fix the code to use write barriers on heap memory, and no
write barriers on stack memory.

These errors were discoverd as part of fixing #27695. They may
have something to do with that issue, but hard to be sure.
The core cause is different, so this fix is a separate CL.

Update #27695

Change-Id: Ib005f6b3308de340be83c3d07d049d5e316b1e3c
Reviewed-on: https://go-review.googlesource.com/137438
Reviewed-by: Austin Clements <austin@google.com>
2018-09-26 21:12:16 +00:00
Keith Randall 78ce3a0368 reflect: use a bigger object when we need a finalizer to run
If an object is allocated as part of a tinyalloc, then other live
objects in the same tinyalloc chunk keep the finalizer from being run,
even if the object that has the finalizer is dead.

Make sure the object we're setting the finalizer on is big enough
to not trigger tinyalloc allocation.

Fixes #26857
Update #21717

Change-Id: I56ad8679426283237ebff20a0da6c9cf64eb1c27
Reviewed-on: https://go-review.googlesource.com/128475
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-08-24 22:17:54 +00:00
Alan Donovan ede5958385 reflect: add Value.MapRange method and MapIter type
Example of use:

	iter := reflect.ValueOf(m).MapRange()
 	for iter.Next() {
		k := iter.Key()
		v := iter.Value()
		...
	}

See issue golang/go#11104

Q. Are there any benchmarks that would exercise the new calls to
   copyval in existing code?

Change-Id: Ic469fcab5f1d9d853e76225f89bde01ee1d36e7a
Reviewed-on: https://go-review.googlesource.com/33572
Reviewed-by: Keith Randall <khr@golang.org>
2018-08-22 20:16:01 +00:00
Ian Lance Taylor 997d7a1893 reflect: remove struct tags from unexported types
Before CL 4281055 in 2011, the reflect package was quite different.
rtype, then called commonType, was embedded in exported structs with
names like StructType. In order to avoid accidental conversions
between pointers to these public structs, which sometimes had
identical fields, the embedded commonType fields were tagged.

In CL 4281055 the formerly public structs were unexported, and all
access was done through the Type interface. At that point the field
tags in the reflect structs were no longer useful.

In Go 1.8 the language was changed to ignore struct field tags when
converting between types. This made the field tags in the reflect
structs doubly useless.

This CL simply removes them.

Fixes #20914

Change-Id: I9af4d6d0709276a91a6b6ee5323cad9dcd0cd0a0
Reviewed-on: https://go-review.googlesource.com/121475
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-06-28 23:06:00 +00:00
Ian Lance Taylor 83092a40ac reflect: prevent additional StructOf embedded method cases
The current implementation does not generate wrappers for methods of
embedded non-interface types. We can only skip the wrapper if
kindDirectIface of the generated struct type matches kindDirectIface
of the embedded type. Panic if that is not the case.

It would be better to actually generate wrappers, but that can be done
later.

Updates #15924
Fixes #24782

Change-Id: I01f5c76d9a07f44e1b04861bfe9f9916a04e65ca
Reviewed-on: https://go-review.googlesource.com/121316
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-06-27 22:04:08 +00:00
Ian Lance Taylor 6decd3d984 reflect: add StructOf test case that gccgo used to fail
Updates #25284

Change-Id: I8ca382dd85b428ad6899d9277cf7f3ce34e35e9a
Reviewed-on: https://go-review.googlesource.com/116416
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2018-06-06 14:08:42 +00:00
Ian Lance Taylor e7ee3b91c4 reflect: check that types match without calling TypeOf
gccgo fails this test before CL 115577.

Updates #25284

Change-Id: Id4550b7b3e268f3c294420ed31c57ad3f1002b5e
Reviewed-on: https://go-review.googlesource.com/115635
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2018-06-05 20:00:37 +00:00
Zhou Peng c4f9fa1f8e reflect: reuse values during comparison of maps in DeepEqual
Change-Id: I82f999b8ed9434321a361bf1bcbed7cf6ee4bee6
Reviewed-on: https://go-review.googlesource.com/115475
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-05-31 15:18:53 +00:00
Alberto Donizetti 377567edd0 reflect: document that StructOf panics on unexported fields
Fixes #25401

Change-Id: I0b61ecfcee43ebfe0a84b5c1e28a3817f96b94ed
Reviewed-on: https://go-review.googlesource.com/115015
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-05-29 17:06:37 +00:00
Robert Griesemer 47be3d49c7 reflect: use 'defined' rather than 'named', use 'embedded' rather than 'anonymous'
On the API level this is just an update of the documentation to match
the current spec more closely.

On the implementation side, this is a rename of various unexported names.

For #22005.

Change-Id: Ie5ae32f3b10f003805240efcceab3d0fd373cd51
Reviewed-on: https://go-review.googlesource.com/112717
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-05-10 23:19:40 +00:00
Richard Musiol 35ea62468b runtime: add js/wasm architecture
This commit adds the js/wasm architecture to the runtime package.
Currently WebAssembly has no support for threads yet, see
https://github.com/WebAssembly/design/issues/1073. Because of that,
there is no preemption of goroutines and no sysmon goroutine.

Design doc: https://docs.google.com/document/d/131vjr4DH6JFnb-blm_uRdaC0_Nv3OUwjEY5qVCxCup4
About WebAssembly assembly files: https://docs.google.com/document/d/1GRmy3rA4DiYtBlX-I1Jr_iHykbX8EixC3Mq0TCYqbKc

Updates #18892

Change-Id: I7f12d21b5180500d55ae9fd2f7e926a1731db391
Reviewed-on: https://go-review.googlesource.com/103877
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-05-08 00:17:34 +00:00
Martin Möhrmann 4ebc67d334 runtime: remove hmap field from maptypes
The hmap field in the maptype is only used by the runtime to check the sizes of
the hmap structure created by the compiler and runtime agree.

Comments are already present about the hmap structure definitions in the
compiler and runtime needing to be in sync.

Add a test that checks the runtimes hmap size is as expected to detect
when the compilers and runtimes hmap sizes diverge instead of checking
this at runtime when a map is created.

Change-Id: I974945ebfdb66883a896386a17bbcae62a18cf2a
Reviewed-on: https://go-review.googlesource.com/91796
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2018-05-06 05:46:06 +00:00
Tobias Klauser 47435b1da1 reflect: define MyBuffer more locally in TestImplicitMapConversion
There are no strange messages anymore, so define type MyBuffer in the
block where it is used.

Change-Id: Ic65b15dc76a40f6f734d9ac2116338502fbb66fd
Reviewed-on: https://go-review.googlesource.com/107735
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-04-18 12:47:39 +00:00
Matthew Dempsky 86a338960d reflect: sort exported methods first
By moving exported methods to the front of method lists, filtering
down to only the exported methods just needs a count of how many
exported methods exist, which the compiler can statically
provide. This allows getting rid of the exported method cache.

For #22075.

Change-Id: I8eeb274563a2940e1347c34d673f843ae2569064
Reviewed-on: https://go-review.googlesource.com/100846
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-03-15 21:56:08 +00:00
Martin Möhrmann 1dbe4c50f2 reflect: avoid calling common if type is known to be *rtype
If the type of Type is known to be *rtype than the common
function is a no-op and does not need to be called.

name  old time/op  new time/op  delta
New   31.0ns ± 5%  30.2ns ± 4%  -2.74%  (p=0.008 n=20+20)

Change-Id: I5d00346dbc782e34c530166d1ee0499b24068b51
Reviewed-on: https://go-review.googlesource.com/96115
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-02-22 07:18:15 +00:00
Martin Möhrmann f4bb25c937 runtime: rename map implementation and test files to use a common prefix
Rename all map implementation and test files to use "map"
as a file name prefix instead of "hashmap" for the implementation
and "map" for the test file names.

Change-Id: I7b317c1f7a660b95c6d1f1a185866f2839e69446
Reviewed-on: https://go-review.googlesource.com/90336
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-02-17 14:57:32 +00:00
Ian Lance Taylor 9558ba293f reflect: add embedded field test
Gccgo failed this test.

Updates #23620

Change-Id: I3979a6d3b87d2d014850accf9cb7f356349e6195
Reviewed-on: https://go-review.googlesource.com/91138
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2018-02-14 15:28:25 +00:00
Mark Rushakoff 24cdb0f965 doc: fix typo in OverflowInt godoc
Change-Id: I426310e0c05c2b4a0123299ade0fe11721d40b10
GitHub-Last-Rev: 651c0291d6
GitHub-Pull-Request: golang/go#23801
Reviewed-on: https://go-review.googlesource.com/93475
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-02-13 03:02:09 +00:00
Russ Cox b26c88db2f reflect: fix doc nit
Type values being comparable implies that Type is a valid map key type.
As previously written, they sound unrelated.

Change-Id: I8e2235275d62898bfb47de850e8257b51ab5cbd6
Reviewed-on: https://go-review.googlesource.com/87021
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-01-09 21:48:16 +00:00
Tim Cooper 6317adeed7 reflect: explicitly state that Type values can be used as map keys
Fixes #6535

Change-Id: I34974c0050424c96d19ad69bf4522bb69cde2fd5
Reviewed-on: https://go-review.googlesource.com/85815
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-01-02 13:39:20 +00:00
Russ Cox 8bb51a73e9 reflect: audit and explain safety of all unsafe.Pointer additions
It's not safe to do p+x with unsafe if that would point past the
end of the object. (Valid in C, not safe in Go.)
Pass a "whySafe" reason (compiled away) to explain at each
call site why it's safe.

Fixes #21733.

Change-Id: I5da8c25bde66f5c9beac232f2135dcab8e8bf3b1
Reviewed-on: https://go-review.googlesource.com/80738
Reviewed-by: Austin Clements <austin@google.com>
2017-12-01 21:05:40 +00:00
Russ Cox eafa29bdce reflect: fix interface to interface conversion in Call
Call is meant to mirror the language semantics, which allow:

	var r io.ReadWriter
	f := func(io.Reader){}
	f(r)

even though the conversion from io.ReadWriter to io.Reader is
being applied to a nil interface. This is different from an explicit
conversion:

	_ = r.(io.Reader)
	f(r.(io.Reader))

Both of those lines panic, but the implicit conversion does not.

By using E2I, which is the implementation of the explicit conversion,
the reflect.Call equivalent of f(r) was inadvertently panicking.
Avoid the panic.

Fixes #22143.

Change-Id: I6b2f5b808e0cd3b89ae8bc75881e307bf1c25558
Reviewed-on: https://go-review.googlesource.com/80736
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-12-01 15:31:31 +00:00
Daniel Martí 7cb3e4fb1d all: unindent some if bodies by exiting early
All of these had a return or break in the else body, so flipping the
condition means we can unindent and simplify.

Change-Id: If93e97504480d18a0dac3f2c8ffe57ab8bcb929c
Reviewed-on: https://go-review.googlesource.com/74190
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-31 20:07:46 +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
Matthew Dempsky 6f1724ff41 reflect: fix method indexing for non-ASCII exported methods
Currently, methods are sorted by name. This happens to guarantee that
exported ASCII methods appear before non-exported ASCII methods, but
this breaks down when Unicode method names are considered.

Type.Method already accounts for this by always indexing into the
slice returned by exportedMethods. This CL makes Value.Method do the
same.

Fixes #22073.

Change-Id: I9bfc6bbfb7353e0bd3c439a15d1c3da60d16d209
Reviewed-on: https://go-review.googlesource.com/66770
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-09-28 18:06:53 +00:00
Joe Tsai d94078f040 reflect: add URL scheme for godoc hyperlinking
Adding the "https://" scheme allows godoc to properly detect
the URL and provide a hyperlink for it.

Change-Id: I76dc309368c86975de01bc6e6e9196037b2114d7
Reviewed-on: https://go-review.googlesource.com/66570
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-09-27 18:23:25 +00:00
Matthew Dempsky 6471ace2ea reflect: fix mutability of non-exported embedded fields
The reflect API normally grants only read-only access to non-exported
fields, but it specially handles non-exported embedded fields so that
users can still fully access promoted fields and methods. For example,
if v.Field(i) refers to a non-exported embedded field, it would be
limited to RO access. But if v.Field(i).Field(j) is an exported field,
then the resulting Value will have full access.

However, the way this was implemented allowed other operations to be
interspersed between the Field calls, which could grant inappropriate
access.

Relatedly, Elem() is safe to use on pointer-embeddings, but it was
also being allowed on embeddings of interface types. This is
inappropriate because it could allow accessing methods of the dynamic
value's complete method set, not just those that were promoted via the
interface embedding.

Fixes #22031.
Fixes #22053.

Change-Id: I9db9be88583f1c1d80c1b4705a76f23a4379182f
Reviewed-on: https://go-review.googlesource.com/66331
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-09-27 18:03:28 +00:00
Cherry Zhang 0a48185b43 reflect: fix pointer past-the-end in Call with zero-sized return value
If a function with nonzero frame but zero-sized return value is
Call'd, we may write a past-the-end pointer in preparing the
return Values. Fix by return the zero value for zero-sized
return value.

Fixes #21717.

Change-Id: I5351cd86d898467170a888b4c3fc9392f0e7aa3b
Reviewed-on: https://go-review.googlesource.com/60811
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-09-19 20:45:24 +00:00
Kunpei Sakai 5a986eca86 all: fix article typos
a -> an

Change-Id: I7362bdc199e83073a712be657f5d9ba16df3077e
Reviewed-on: https://go-review.googlesource.com/63850
Reviewed-by: Rob Pike <r@golang.org>
2017-09-15 02:39:16 +00:00
Matthew Dempsky d349fa25df cmd/compile: fix and improve struct field reflect information
The previous logic was overly complicated, generated suboptimally
encoded struct type descriptors, and mishandled embeddings of
predeclared universal types.

Fixes #21122.
Fixes #21353.
Fixes #21696.
Fixes #21702.
Updates #21357.

Change-Id: If34761fa6dbe4af2af59dee501e7f30845320376
Reviewed-on: https://go-review.googlesource.com/60410
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-09-05 18:09:41 +00:00
André Carvalho 77b4beba2f reflect: handle types with unexported methods before exported ones
The method Method expects index to be an index of exported fields,
but, before this change, the index used by MethodByName could
take into account unexported fields if those happened sort
before the exported one.

Fixes #21177

Change-Id: I90bb64a47b23e2e43fdd2b8a1e0a2c9a8a63ded2
Reviewed-on: https://go-review.googlesource.com/51810
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-23 23:48:49 +00:00
Daniel Martí 9c9df65c53 reflect: remove useless parameter from newName
pkgPath always received the empty string. Worse yet, it panicked if it
received anything else. This has been the case ever since newName was
introduced in early 2016.

Change-Id: I5f164305bd30c34455ef35e776c7616f303b37e4
Reviewed-on: https://go-review.googlesource.com/54331
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-08-16 15:11:03 +00:00
Martin Möhrmann 8a6e51aede cmd/compile: generate makechan calls with int arguments
Where possible generate calls to runtime makechan with int arguments
during compile time instead of makechan with int64 arguments.

This eliminates converting arguments for calls to makechan with
int64 arguments for platforms where int64 values do not fit into
arguments of type int.

A similar optimization for makeslice was introduced in CL
golang.org/cl/27851.

386:
name                old time/op  new time/op  delta
MakeChan/Byte       52.4ns ± 6%  45.0ns ± 1%  -14.14%  (p=0.000 n=10+10)
MakeChan/Int        54.5ns ± 1%  49.1ns ± 1%   -9.87%  (p=0.000 n=10+10)
MakeChan/Ptr         150ns ± 1%   143ns ± 0%   -4.38%  (p=0.000 n=9+7)
MakeChan/Struct/0   49.2ns ± 2%  43.2ns ± 2%  -12.27%  (p=0.000 n=10+10)
MakeChan/Struct/32  81.7ns ± 2%  76.2ns ± 1%   -6.71%  (p=0.000 n=10+10)
MakeChan/Struct/40  88.4ns ± 2%  82.5ns ± 2%   -6.60%  (p=0.000 n=10+10)

AMD64:
name                old time/op  new time/op  delta
MakeChan/Byte       83.4ns ± 8%  80.8ns ± 3%    ~     (p=0.171 n=10+10)
MakeChan/Int         101ns ± 3%   101ns ± 2%    ~     (p=0.412 n=10+10)
MakeChan/Ptr         128ns ± 1%   128ns ± 1%    ~     (p=0.191 n=10+10)
MakeChan/Struct/0   67.6ns ± 3%  68.7ns ± 4%    ~     (p=0.224 n=10+10)
MakeChan/Struct/32   138ns ± 1%   139ns ± 1%    ~     (p=0.185 n=10+9)
MakeChan/Struct/40   154ns ± 1%   154ns ± 1%  -0.55%  (p=0.027 n=10+9)

Change-Id: Ie854cb066007232c5e9f71ea7d6fe27e81a9c050
Reviewed-on: https://go-review.googlesource.com/55140
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-15 05:54:24 +00:00
Keith Randall 04d6f982ae runtime: remove link field from itab
We don't use it any more, remove it.

Change-Id: I76ce1a4c2e7048fdd13a37d3718b5abf39ed9d26
Reviewed-on: https://go-review.googlesource.com/44474
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-08-15 01:52:35 +00:00
Keith Randall 98d0634b7a runtime: remove bad field from itab
Just use fun[0]==0 to indicate a bad itab.

Change-Id: I28ecb2d2d857090c1ecc40b1d1866ac24a844848
Reviewed-on: https://go-review.googlesource.com/44473
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-08-15 01:52:29 +00:00
Keith Randall 3d1699ea78 runtime: new itab lookup table
Keep itabs in a growable hash table.
Use a simple open-addressable hash table, quadratic probing, power
of two sized.
Synchronization gets a bit more tricky. The common read path now
has two atomic reads, one to get the table pointer and one to read
the entry out of the table.

I set the max load factor to 75%, kind of arbitrarily. There's a
space-speed tradeoff here, and I'm not sure where we should land.

Because we use open addressing the itab.link field is no longer needed.
I'll remove it in a separate CL.

Fixes #20505

Change-Id: Ifb3d9a337512d6cf968c1fceb1eeaf89559afebf
Reviewed-on: https://go-review.googlesource.com/44472
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-08-15 01:52:23 +00:00
Ian Lance Taylor a279b53a18 reflect: document how DeepEqual handles cycles
Fixes #20428

Change-Id: Ia450e615728efd4ccb6e42117b547cac162f13a3
Reviewed-on: https://go-review.googlesource.com/52931
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2017-08-04 22:22:03 +00:00
Ian Lance Taylor 87d5f6b9f6 reflect: make StructOf panic for methods that don't work
When StructOf is used with an anonymous field that has methods, and
that anonymous field is not the first field, the methods we generate
are incorrect because they do not offset to the field as required.
If we encounter that case, panic rather than doing the wrong thing.

Fixes #20824
Updates #15924

Change-Id: I3b0901ddbc6d58af5f7e84660b5e3085a431035d
Reviewed-on: https://go-review.googlesource.com/47035
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-07-15 00:47:41 +00:00
Emmanuel Odeke 79e1505e3b reflect: match MakeMapWithSize docs about initial capacity with spec
Following the spec clarification in CL 40393, copy that text
to reflect docs to state that the initial capacity of MakeMapWithSize
is a hint/approximate.

Fixes #19903

Change-Id: I6b3315b8183cafaa61fbb2839a4e42b76fd71544
Reviewed-on: https://go-review.googlesource.com/46270
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-07-06 04:04:20 +00:00
Ian Lance Taylor 7e4d1a05e5 reflect: document that value.NumMethod counts exported methods
Updates #17686
Fixes #20848

Change-Id: I35d58c7d1aa74d3e7867124070e27c787d444b04
Reviewed-on: https://go-review.googlesource.com/47210
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-06-29 15:28:16 +00:00
Pravendra Singh 538b3a5f37 reflect: prevent structs with invalid field name
According to the language spec, a struct field name should
be an identifier.

  identifier = letter { letter | unicode_digit } .
  letter = unicode_letter | "_" .

Implements a function 'isValidFieldName(fieldName string) bool'.
To check if the field name is a valid identifier or not.
It will panic if the field name is invalid.

It uses the non-exported function implementation 'isLetter'
from the package 'scanner', used to parse an identifier.

Fixes #20600.

Change-Id: I1db7db1ad88cab5dbea6565be15cc7461cc56c44
Reviewed-on: https://go-review.googlesource.com/45590
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-06-13 21:51:17 +00:00
Ian Lance Taylor 2ddc3e940e reflect: check pkgPath for unexported methods in Implements
Fixes #20541.

Change-Id: Ifdfdf3616482b71761daf6d114b779a8ec532051
Reviewed-on: https://go-review.googlesource.com/44495
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-06-08 00:54:14 +00:00
Daniel Martí 19b05acd13 reflect: remove dead v.typ assignment
v is not a pointer receiver, and v.typ isn't used in the lines below.
The assignment is dead. Remove it.

Keep the comment, as it refers to the whole case block and not just the
removed line.

Change-Id: Icb2d20c287d9a41bf620ebe5cdec764cd84178a7
Reviewed-on: https://go-review.googlesource.com/43134
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-05-11 08:07:21 +00:00
Daniel Martí 9bced47706 reflect: don't panic in ArrayOf if elem size is 0
We do a division by the elem type size to check if the array size would
be too large for the virtual address space. This is a silly check if the
size is 0, but the problem is that it means a division by zero and a
panic.

Since arrays of empty structs are valid in a regular program, make them
also work in reflect.

Use a separate, explicit test with struct{}{} to make sure the test for
a zero-sized type is not confused with the rest.

Fixes #20313.

Change-Id: I47b8b87e6541631280b79227bdea6a0f6035c9e0
Reviewed-on: https://go-review.googlesource.com/43131
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-05-10 13:44:53 +00:00
Daniel Martí a4864094f0 reflect: fix String of new array types
When constructing a new type for an array type in ArrayOf, we don't
reset tflag to 0. All the other methods in the package, such as SliceOf,
do this already. This results in the new array type having weird issues
when being printed, such as having tflagExtraStar set when it shouldn't.

That flag removes the first char to get rid of '*', but when used
incorrectly in this case it eats the '[' character leading to broken
strings like "3]int".

This was fixed in 56752eb2 for issue #16722, but ArrayOf was missed.

Also make the XM test struct have a non-zero size as that leads to a
division by zero panic in ArrayOf.

Fixes #20311.

Change-Id: I18f1027fdbe9f71767201e7424269c3ceeb23eb5
Reviewed-on: https://go-review.googlesource.com/43130
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-05-10 11:42:46 +00:00
Bryan C. Mills 33b92cd6ce reflect: use sync.Map instead of RWMutex for type caches
This provides a significant speedup when using reflection-heavy code
on many CPU cores, such as when marshaling or unmarshaling protocol
buffers.

updates #17973
updates #18177

name                       old time/op    new time/op     delta
Call                          239ns ±10%      245ns ± 7%       ~     (p=0.562 n=10+9)
Call-6                        201ns ±38%       48ns ±29%    -76.39%  (p=0.000 n=10+9)
Call-48                       133ns ± 8%       12ns ± 2%    -90.92%  (p=0.000 n=10+8)
CallArgCopy/size=128          169ns ±12%      197ns ± 2%    +16.35%  (p=0.000 n=10+7)
CallArgCopy/size=128-6        142ns ± 9%       34ns ± 7%    -76.10%  (p=0.000 n=10+9)
CallArgCopy/size=128-48       125ns ± 3%        9ns ± 7%    -93.01%  (p=0.000 n=8+8)
CallArgCopy/size=256          177ns ± 8%      197ns ± 5%    +11.24%  (p=0.000 n=10+9)
CallArgCopy/size=256-6        148ns ±11%       35ns ± 6%    -76.23%  (p=0.000 n=10+9)
CallArgCopy/size=256-48       127ns ± 4%        9ns ± 9%    -92.66%  (p=0.000 n=10+9)
CallArgCopy/size=1024         196ns ± 6%      228ns ± 7%    +16.09%  (p=0.000 n=10+9)
CallArgCopy/size=1024-6       143ns ± 6%       42ns ± 5%    -70.39%  (p=0.000 n=8+8)
CallArgCopy/size=1024-48      130ns ± 7%       10ns ± 1%    -91.99%  (p=0.000 n=10+8)
CallArgCopy/size=4096         330ns ± 9%      351ns ± 5%     +6.20%  (p=0.004 n=10+9)
CallArgCopy/size=4096-6       173ns ±14%       62ns ± 6%    -63.83%  (p=0.000 n=10+8)
CallArgCopy/size=4096-48      141ns ± 6%       15ns ± 6%    -89.59%  (p=0.000 n=10+8)
CallArgCopy/size=65536       7.71µs ±10%     7.74µs ±10%       ~     (p=0.859 n=10+9)
CallArgCopy/size=65536-6     1.33µs ± 4%     1.34µs ± 6%       ~     (p=0.720 n=10+9)
CallArgCopy/size=65536-48     347ns ± 2%      344ns ± 2%       ~     (p=0.202 n=10+9)
PtrTo                        30.2ns ±10%     41.3ns ±11%    +36.97%  (p=0.000 n=10+9)
PtrTo-6                       126ns ± 6%        7ns ±10%    -94.47%  (p=0.000 n=9+9)
PtrTo-48                     86.9ns ± 9%      1.7ns ± 9%    -98.08%  (p=0.000 n=10+9)
FieldByName1                 86.6ns ± 5%     87.3ns ± 7%       ~     (p=0.737 n=10+9)
FieldByName1-6               19.8ns ±10%     18.7ns ±10%       ~     (p=0.073 n=9+9)
FieldByName1-48              7.54ns ± 4%     7.74ns ± 5%     +2.55%  (p=0.023 n=9+9)
FieldByName2                 1.63µs ± 8%     1.70µs ± 4%     +4.13%  (p=0.020 n=9+9)
FieldByName2-6                481ns ± 6%      490ns ±10%       ~     (p=0.474 n=9+9)
FieldByName2-48               723ns ± 3%      736ns ± 2%     +1.76%  (p=0.045 n=8+8)
FieldByName3                 10.5µs ± 7%     10.8µs ± 7%       ~     (p=0.234 n=8+8)
FieldByName3-6               2.78µs ± 3%     2.94µs ±10%     +5.87%  (p=0.031 n=9+9)
FieldByName3-48              3.72µs ± 2%     3.91µs ± 5%     +4.91%  (p=0.003 n=9+9)
InterfaceBig                 10.8ns ± 5%     10.7ns ± 5%       ~     (p=0.849 n=9+9)
InterfaceBig-6               9.62ns ±81%     1.79ns ± 4%    -81.38%  (p=0.003 n=9+9)
InterfaceBig-48              0.48ns ±34%     0.50ns ± 7%       ~     (p=0.071 n=8+9)
InterfaceSmall               10.7ns ± 5%     10.9ns ± 4%       ~     (p=0.243 n=9+9)
InterfaceSmall-6             1.85ns ± 5%     1.79ns ± 1%     -2.97%  (p=0.006 n=7+8)
InterfaceSmall-48            0.49ns ±20%     0.48ns ± 5%       ~     (p=0.740 n=7+9)
New                          28.2ns ±20%     26.6ns ± 3%       ~     (p=0.617 n=9+9)
New-6                        4.69ns ± 4%     4.44ns ± 3%     -5.33%  (p=0.001 n=9+9)
New-48                       1.10ns ± 9%     1.08ns ± 6%       ~     (p=0.285 n=9+8)

name                       old alloc/op   new alloc/op    delta
Call                          0.00B           0.00B            ~     (all equal)
Call-6                        0.00B           0.00B            ~     (all equal)
Call-48                       0.00B           0.00B            ~     (all equal)

name                       old allocs/op  new allocs/op   delta
Call                           0.00            0.00            ~     (all equal)
Call-6                         0.00            0.00            ~     (all equal)
Call-48                        0.00            0.00            ~     (all equal)

name                       old speed      new speed       delta
CallArgCopy/size=128        757MB/s ±11%    649MB/s ± 1%    -14.33%  (p=0.000 n=10+7)
CallArgCopy/size=128-6      901MB/s ± 9%   3781MB/s ± 7%   +319.69%  (p=0.000 n=10+9)
CallArgCopy/size=128-48    1.02GB/s ± 2%  14.63GB/s ± 6%  +1337.98%  (p=0.000 n=8+8)
CallArgCopy/size=256       1.45GB/s ± 9%   1.30GB/s ± 5%    -10.17%  (p=0.000 n=10+9)
CallArgCopy/size=256-6     1.73GB/s ±11%   7.28GB/s ± 7%   +320.76%  (p=0.000 n=10+9)
CallArgCopy/size=256-48    2.00GB/s ± 4%  27.46GB/s ± 9%  +1270.85%  (p=0.000 n=10+9)
CallArgCopy/size=1024      5.21GB/s ± 6%   4.49GB/s ± 8%    -13.74%  (p=0.000 n=10+9)
CallArgCopy/size=1024-6    7.18GB/s ± 7%  24.17GB/s ± 5%   +236.64%  (p=0.000 n=9+8)
CallArgCopy/size=1024-48   7.87GB/s ± 7%  98.43GB/s ± 1%  +1150.99%  (p=0.000 n=10+8)
CallArgCopy/size=4096      12.3GB/s ± 6%   11.7GB/s ± 5%     -5.00%  (p=0.008 n=9+9)
CallArgCopy/size=4096-6    23.8GB/s ±16%   65.6GB/s ± 5%   +175.02%  (p=0.000 n=10+8)
CallArgCopy/size=4096-48   29.0GB/s ± 7%  279.6GB/s ± 6%   +862.87%  (p=0.000 n=10+8)
CallArgCopy/size=65536     8.52GB/s ±11%   8.49GB/s ± 9%       ~     (p=0.842 n=10+9)
CallArgCopy/size=65536-6   49.3GB/s ± 4%   49.0GB/s ± 6%       ~     (p=0.720 n=10+9)
CallArgCopy/size=65536-48   189GB/s ± 2%    190GB/s ± 2%       ~     (p=0.211 n=10+9)

https://perf.golang.org/search?q=upload:20170426.3

Change-Id: Iff68f18ef69defb7f30962e21736ac7685a48a27
Reviewed-on: https://go-review.googlesource.com/41871
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-27 15:34:41 +00:00
Bryan C. Mills f5f5a00b92 reflect: parallelize benchmarks
Add a benchmark for PtrTo: it's the motivation for #17973, which is
the motivation for #18177.

Results remain comparable with the non-parallel version with -cpu=1:

benchmark                             old ns/op     new ns/op     delta
BenchmarkCall                         357           360           +0.84%
BenchmarkCall-6                       90.3          90.7          +0.44%
BenchmarkCallArgCopy/size=128         319           323           +1.25%
BenchmarkCallArgCopy/size=128-6       329           82.2          -75.02%
BenchmarkCallArgCopy/size=256         354           335           -5.37%
BenchmarkCallArgCopy/size=256-6       340           85.2          -74.94%
BenchmarkCallArgCopy/size=1024        374           703           +87.97%
BenchmarkCallArgCopy/size=1024-6      378           95.8          -74.66%
BenchmarkCallArgCopy/size=4096        627           631           +0.64%
BenchmarkCallArgCopy/size=4096-6      643           120           -81.34%
BenchmarkCallArgCopy/size=65536       10502         10169         -3.17%
BenchmarkCallArgCopy/size=65536-6     10298         2240          -78.25%
BenchmarkFieldByName1                 139           132           -5.04%
BenchmarkFieldByName1-6               144           24.9          -82.71%
BenchmarkFieldByName2                 2721          2778          +2.09%
BenchmarkFieldByName2-6               3953          578           -85.38%
BenchmarkFieldByName3                 19136         18357         -4.07%
BenchmarkFieldByName3-6               23072         3850          -83.31%
BenchmarkInterfaceBig                 12.7          15.5          +22.05%
BenchmarkInterfaceBig-6               14.2          2.48          -82.54%
BenchmarkInterfaceSmall               13.1          15.1          +15.27%
BenchmarkInterfaceSmall-6             13.0          2.54          -80.46%
BenchmarkNew                          43.8          43.0          -1.83%
BenchmarkNew-6                        40.5          6.67          -83.53%

benchmark                             old MB/s     new MB/s     speedup
BenchmarkCallArgCopy/size=128         400.24       395.15       0.99x
BenchmarkCallArgCopy/size=128-6       388.74       1557.76      4.01x
BenchmarkCallArgCopy/size=256         722.44       762.44       1.06x
BenchmarkCallArgCopy/size=256-6       751.98       3003.83      3.99x
BenchmarkCallArgCopy/size=1024        2733.22      1455.50      0.53x
BenchmarkCallArgCopy/size=1024-6      2706.40      10687.53     3.95x
BenchmarkCallArgCopy/size=4096        6523.32      6488.25      0.99x
BenchmarkCallArgCopy/size=4096-6      6363.85      34003.09     5.34x
BenchmarkCallArgCopy/size=65536       6239.88      6444.46      1.03x
BenchmarkCallArgCopy/size=65536-6     6363.83      29255.26     4.60x

benchmark           old allocs     new allocs     delta
BenchmarkCall       0              0              +0.00%
BenchmarkCall-6     0              0              +0.00%

benchmark           old bytes     new bytes     delta
BenchmarkCall       0             0             +0.00%
BenchmarkCall-6     0             0             +0.00%

updates #17973
updates #18177

Change-Id: If70c5c742e8d1b138347f4963ad7cff38fffc018
Reviewed-on: https://go-review.googlesource.com/36831
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-26 19:04:30 +00:00
Sebastien Binet 2ef340f271 reflect: document ptrdata field of rtype
This CL adds a simple explanation about what means the ptrdata field of
the reflect.rtype type.
Also document that rtype needs to be kept in sync with the runtime._type
type that rtype mirrors.

Change-Id: Icd9663a2e4bb94d922a2417cfe4537861d2ccc97
Reviewed-on: https://go-review.googlesource.com/40917
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-18 15:30:04 +00:00
Filip Gruszczyński 6c5a819a5e reflect: add MakeMapWithSize for creating maps with size hint
Providing size hint when creating a map allows avoiding re-allocating
underlying data structure if we know how many elements are going to
be inserted. This can be used for example during decoding maps in
gob.

Fixes #19599

Change-Id: I108035fec29391215d2261a73eaed1310b46bab1
Reviewed-on: https://go-review.googlesource.com/38335
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-04-04 20:01:43 +00:00
Austin Clements 627798db4e reflect: fix out-of-bounds pointers calling no-result method
reflect.callReflect heap-allocates a stack frame and then constructs
pointers to the arguments and result areas of that frame. However, if
there are no results, the results pointer will point past the end of
the frame allocation. If there are also no arguments, the arguments
pointer will also point past the end of the frame allocation. If the
GC observes either these pointers, it may panic.

Fix this by not constructing these pointers if these areas of the
frame are empty.

This adds a test of calling no-argument/no-result methods via reflect,
since nothing in std did this before. However, it's quite difficult to
demonstrate the actual failure because it depends on both exact
allocation patterns and on GC scanning the goroutine's stack while
inside one of the typedmemmovepartial calls.

I also audited other uses of typedmemmovepartial and
memclrNoHeapPointers in reflect, since these are the most susceptible
to this. These appear to be the only two cases that can construct
out-of-bounds arguments to these functions.

Fixes #19724.

Change-Id: I4b83c596b5625dc4ad0567b1e281bad4faef972b
Reviewed-on: https://go-review.googlesource.com/38736
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-03-29 15:28:49 +00:00
Daniel Martí 2e29eb57db runtime: remove unused *chantype parameters
The chanrecv funcs don't use it at all. The chansend ones do, but the
element type is now part of the hchan struct, which is already a
parameter.

hchan can be nil in chansend when sending to a nil channel, so when
instrumenting we must copy to the stack to be able to read the channel
type.

name             old time/op  new time/op  delta
ChanUncontended  6.42µs ± 1%  6.22µs ± 0%  -3.06%  (p=0.000 n=19+18)

Initially found by github.com/mvdan/unparam.

Fixes #19591.

Change-Id: I3a5e8a0082e8445cc3f0074695e3593fd9c88412
Reviewed-on: https://go-review.googlesource.com/38351
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-21 17:10:16 +00:00
Ian Lance Taylor b5e5194306 reflect: fix bucketOf to only look at ptrdata entries in gcdata
The gcdata field only records ptrdata entries, not size entries.

Also fix an obsolete comment: the enforced limit on pointer maps is
now 2048 bytes, not 16 bytes.

I wasn't able to contruct a test case for this. It would require
building a type whose size is greater than 64 bytes but less than 128
bytes, with at least one pointer in first 64 bytes but no pointers
after the first 64 bytes, such that the linker arranges for the one
byte gcbits value to be immediately followed by a non-zero byte.

Change-Id: I9118d3e4ec6f07fd18b72f621c1e5f4fdfe5f80b
Reviewed-on: https://go-review.googlesource.com/37142
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-02-22 02:19:48 +00:00
Koki Ide 045ad5bab8 all: fix a few typos in comments
Change-Id: I0455ffaa51c661803d8013c7961910f920d3c3cc
Reviewed-on: https://go-review.googlesource.com/37043
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-17 18:15:41 +00:00
Michael Hudson-Doyle 066ac428cd reflect: clear ptrToThis in Ptr when allocating result on heap
Otherwise, calling PtrTo on the result will fail.

Fixes #19003

Change-Id: I8d7d1981a5d0417d5aee52740469d71e90734963
Reviewed-on: https://go-review.googlesource.com/36731
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-02-10 17:22:07 +00:00
Joe Tsai 048b8cecc6 reflect: adjust documentation on Value
Make the documentation more explicit that it is not safe to directly
compare Value. Get straight to the point on how to do it correctly.

Updates #18871

Change-Id: I2aa3253f779636b2f72a1aae8c9bb45d3c32c902
Reviewed-on: https://go-review.googlesource.com/36018
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-01 19:11:34 +00:00
Russ Cox c47df7ae17 all: merge dev.typealias into master
For #18130.

f8b4123613 [dev.typealias] spec: use term 'embedded field' rather than 'anonymous field'
9ecc3ee252 [dev.typealias] cmd/compile: avoid false positive cycles from type aliases
49b7af8a30 [dev.typealias] reflect: add test for type aliases
9bbb07ddec [dev.typealias] cmd/compile, reflect: fix struct field names for embedded byte, rune
43c7094386 [dev.typealias] reflect: fix StructOf use of StructField to match StructField docs
9657e0b077 [dev.typealias] cmd/doc: update for type alias
de2e5459ae [dev.typealias] cmd/compile: declare methods after resolving receiver type
9259f3073a [dev.typealias] test: match gccgo error messages on alias2.go
5d92916770 [dev.typealias] cmd/compile: change Func.Shortname to *Sym
a7c884efc1 [dev.typealias] go/internal/gccgoimporter: support for type aliases
5802cfd900 [dev.typealias] cmd/compile: export/import test cases for type aliases
d7cabd40dd [dev.typealias] go/types: clarified doc string
cc2dcce3d7 [dev.typealias] cmd/compile: a few better comments related to alias types
5c160b28ba [dev.typealias] cmd/compile: improved error message for cyles involving type aliases
b2386dffa1 [dev.typealias] cmd/compile: type-check type alias declarations
ac8421f9a5 [dev.typealias] cmd/compile: various minor cleanups
f011e0c6c3 [dev.typealias] cmd/compile, go/types, go/importer: various alias related fixes
49de5f0351 [dev.typealias] cmd/compile, go/importer: define export format and implement importing of type aliases
5ceec42dc0 [dev.typealias] go/types: export TypeName.IsAlias so clients can use it
aa1f0681bc [dev.typealias] go/types: improved Object printing
c80748e389 [dev.typealias] go/types: remove some more vestiges of prior alias implementation
80d8b69e95 [dev.typealias] go/types: implement type aliases
a917097b5e [dev.typealias] go/build: add go1.9 build tag
3e11940437 [dev.typealias] cmd/compile: recognize type aliases but complain for now (not yet supported)
e0a05c274a [dev.typealias] cmd/gofmt: added test cases for alias type declarations
2e5116bd99 [dev.typealias] go/ast, go/parser, go/printer, go/types: initial type alias support

Change-Id: Ia65f2e011fd7195f18e1dce67d4d49b80a261203
2017-01-31 13:01:31 -05:00
Russ Cox 49b7af8a30 [dev.typealias] reflect: add test for type aliases
For #18130.

Change-Id: Idd77cb391178c185227cfd779c70fec16351f825
Reviewed-on: https://go-review.googlesource.com/35733
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-01-25 18:57:29 +00:00
Russ Cox 9bbb07ddec [dev.typealias] cmd/compile, reflect: fix struct field names for embedded byte, rune
Will also fix type aliases.

Fixes #17766.
For #18130.

Change-Id: I9e1584d47128782152e06abd0a30ef423d5c30d2
Reviewed-on: https://go-review.googlesource.com/35732
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-01-25 18:57:20 +00:00
Russ Cox 43c7094386 [dev.typealias] reflect: fix StructOf use of StructField to match StructField docs
The runtime internal structField interprets name=="" as meaning anonymous,
but the exported reflect.StructField has always set Name, even for anonymous
fields, and also set Anonymous=true.

The initial implementation of StructOf confused the internal and public
meanings of the StructField, expecting the runtime representation of
anonymous fields instead of the exported reflect API representation.
It also did not document this fact, so that users had no way to know how
to create an anonymous field.

This CL changes StructOf to use the previously documented interpretation
of reflect.StructField instead of an undocumented one.

The implementation of StructOf also, in some cases, allowed creating
structs with unexported fields (if you knew how to ask) but set the
PkgPath incorrectly on those fields. Rather than try to fix that, this CL
changes StructOf to reject attempts to create unexported fields.
(I think that may be the right design choice, not just a temporary limitation.
In any event, it's not the topic for today's work.)

For #17766.
Fixes #18780.

Change-Id: I585a4e324dc5a90551f49d21ae04d2de9ea04b6c
Reviewed-on: https://go-review.googlesource.com/35731
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-01-25 18:56:51 +00:00
Austin Clements 22689c4450 reflect: keep makeFuncImpl live across makeFuncStub
When traceback sees reflect.makeFuncStub (or reflect.methodValueCall)
on the stack, it expects to be able to get the *reflect.makeFuncImpl
(or *reflect.methodValue) for that call from the first outgoing
argument slot of makeFuncStub/methodValueCall.

However, currently this object isn't necessarily kept live across
makeFuncStub. This means it may get garbage collected while in a
reflect call and reused for something else. If we then try to
traceback, the runtime will see a corrupted makeFuncImpl object and
panic. This was not a problem in previous releases because we always
kept arguments live across the whole function. This became a problem
when we stopped doing this.

Fix this by using reflect.KeepAlive to keep the
makeFuncImpl/methodValue live across all of callReflect/callMethod,
which in turn keeps it live as long as makeFuncStub/methodValueCall
are on the stack.

Fixes #18635.

Change-Id: I91853efcf17912390fddedfb0230648391c33936
Reviewed-on: https://go-review.googlesource.com/35151
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-01-13 03:45:28 +00:00
Austin Clements ddd558e7e4 runtime: clean up and improve reflect.methodValue comments
The runtime no longer hard-codes the offset of
reflect.methodValue.stack, so remove these obsolete comments. Also,
reflect.methodValue and runtime.reflectMethodValue must also agree
with reflect.makeFuncImpl, so update the comments on all three to
mention this.

This was pointed out by Minux on CL 31138.

Change-Id: Ic5ed1beffb65db76aca2977958da35de902e8e58
Reviewed-on: https://go-review.googlesource.com/34590
Reviewed-by: Keith Randall <khr@golang.org>
2016-12-19 21:02:53 +00:00
Sebastien Binet 6c7978fc89 reflect: add example for StructOf
This CL adds a simple example for StructOf.
The example shows how StructOf can be used in a JSON roundtrip.

Change-Id: I9ff1ea9cb8c0cf297c5fae74e68b89931076adfd
Reviewed-on: https://go-review.googlesource.com/33953
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-12-06 20:18:12 +00:00
Ian Lance Taylor b1dbc9f8c0 reflect: fix typo in comment
Sigh, forgot to run `git mail`.

Change-Id: Idc49be2bb20d6f0e392cb472a63267ffee2ca22c
Reviewed-on: https://go-review.googlesource.com/33476
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
2016-11-23 01:14:59 +00:00
Ian Lance Taylor 50c4dbced9 reflect: fix size of StructOf ending in zero-sized field
Update #9401.
Fixes #18016.

Change-Id: Icc24dd10dab1ad8e5cf295e0727d437afa5025c0
Reviewed-on: https://go-review.googlesource.com/33475
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-11-23 00:44:01 +00:00
David Crawshaw 6f31abd23a cmd/compile, cmd/link: weak relocation for ptrTo
Introduce R_WEAKADDROFF, a "weak" variation of the R_ADDROFF relocation
that will only reference the type described if it is in some other way
reachable.

Use this for the ptrToThis field in reflect type information where it
is safe to do so (that is, types that don't need to be included for
interface satisfaction, and types that won't cause the compiler to
recursively generate an endless series of ptr-to-ptr-to-ptr-to...
types).

Also fix a small bug in reflect, where StructOf was not clearing the
ptrToThis field of new types.

Fixes #17931

Change-Id: I4d3b53cb9c916c97b3b16e367794eee142247281
Reviewed-on: https://go-review.googlesource.com/33427
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-22 03:10:14 +00:00
Ian Lance Taylor 011cb64231 cmd/compile, reflect: use field pkgPath if needed
It's possible for the pkgPath of a field to be different than that of
the struct type as a whole. In that case, store the field's pkgPath in
the name field. Use the field's pkgPath when setting PkgPath and when
checking for type identity.

Fixes #17952.

Change-Id: Iebaf92f0054b11427c8f6e4158c3bebcfff06f45
Reviewed-on: https://go-review.googlesource.com/33333
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-11-17 01:19:46 +00:00
David Crawshaw 66477ec830 reflect: rename, document TestUnaddressableField
Change-Id: I94e0f3e4bccd44a67934ddb4d5fc7da57bb8ac9f
Reviewed-on: https://go-review.googlesource.com/33112
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
2016-11-11 14:38:40 +00:00
David Crawshaw 8d0c105407 reflect: unexported fields are tied to a package
An unexported field of a struct is not visible outside of the package
that defines it, so the package path is implicitly part of the
definition of any struct with an unexported field.

Change-Id: I17c6aac822bd0c24188ab8ba1cc406d6b5d82771
Reviewed-on: https://go-review.googlesource.com/32820
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-10 14:06:23 +00:00
Vladimir Stefanovic 1a07257777 reflect: add support for GOARCH=mips{,le}
Change-Id: I8b0c4bfe1e4c401d5c36a51b937671e6362c73a4
Reviewed-on: https://go-review.googlesource.com/31485
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-11-03 23:01:05 +00:00
Jaana Burcu Dogan 398e861d97 reflect: clarify that NumMethod returns only the number of exported methods
Fixes #17686.

Change-Id: I7d07c367e50b448579f9855bea43df76ddb82bd0
Reviewed-on: https://go-review.googlesource.com/32420
Reviewed-by: Rob Pike <r@golang.org>
2016-10-31 17:17:05 +00:00
Austin Clements 87e48c5afd runtime, cmd/compile: rename memclr -> memclrNoHeapPointers
Since barrier-less memclr is only safe in very narrow circumstances,
this commit renames memclr to avoid accidentally calling memclr on
typed memory. This can cause subtle, non-deterministic bugs, so it's
worth some effort to prevent. In the near term, this will also prevent
bugs creeping in from any concurrent CLs that add calls to memclr; if
this happens, whichever patch hits master second will fail to compile.

This also adds the other new memclr variants to the compiler's
builtin.go to minimize the churn on that binary blob. We'll use these
in future commits.

Updates #17503.

Change-Id: I00eead049f5bd35ca107ea525966831f3d1ed9ca
Reviewed-on: https://go-review.googlesource.com/31369
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2016-10-28 18:20:33 +00:00
Austin Clements aa581f5157 runtime: use typedmemclr for typed memory
The hybrid barrier requires distinguishing typed and untyped memory
even when zeroing because the *current* contents of the memory matters
even when overwriting.

This commit introduces runtime.typedmemclr and runtime.memclrHasPointers
as a typed memory clearing functions parallel to runtime.typedmemmove.
Currently these simply call memclr, but with the hybrid barrier we'll
need to shade any pointers we're overwriting. These will provide us
with the necessary hooks to do so.

Updates #17503.

Change-Id: I74478619f8907825898092aaa204d6e4690f27e6
Reviewed-on: https://go-review.googlesource.com/31366
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2016-10-28 18:20:04 +00:00
Austin Clements 79561a84ce runtime: simplify reflectcall write barriers
Currently reflectcall has a subtle dance with write barriers where the
assembly code copies the result values from the stack to the in-heap
argument frame without write barriers and then calls into the runtime
after the fact to invoke the necessary write barriers.

For the hybrid barrier (and for ROC), we need to switch to a
*pre*-write write barrier, which is very difficult to do with the
current setup. We could tie ourselves in knots of subtle reasoning
about why it's okay in this particular case to have a post-write write
barrier, but this commit instead takes a different approach. Rather
than making things more complex, this simplifies reflection calls so
that the argument copy is done in Go using normal bulk write barriers.

The one difficulty with this approach is that calling into Go requires
putting arguments on the stack, but the call* functions "donate" their
entire stack frame to the called function. We can get away with this
now because the copy avoids using the stack and has copied the results
out before we clobber the stack frame to call into the write barrier.
The solution in this CL is to call another function, passing arguments
in registers instead of on the stack, and let that other function
reserve more stack space and setup the arguments for the runtime.

This approach seemed to work out the best. I also tried making the
call* functions reserve 32 extra bytes of frame for the write barrier
arguments and adjust SP up by 32 bytes around the call. However, even
with the necessary changes to the assembler to correct the spdelta
table, the runtime was still having trouble with the frame layout (and
the changes to the assembler caused many other things that do strange
things with the SP to fail to assemble). The approach I took doesn't
require any funny business with the SP.

Updates #17503.

Change-Id: Ie2bb0084b24d6cff38b5afb218b9e0534ad2119e
Reviewed-on: https://go-review.googlesource.com/31655
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-10-26 15:44:44 +00:00
Josh Bleecher Snyder accf5cc386 all: minor vet fixes
Change-Id: I22f0f3e792052762499f632571155768b4052bc9
Reviewed-on: https://go-review.googlesource.com/31759
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-24 17:27:37 +00:00
Russ Cox 19adf8aeaa reflect: fix DeepEqual for some cyclic corner cases
Fixes #15610.

Change-Id: Idbc8a9b328b92034d53b8009471678a166d5cf3f
Reviewed-on: https://go-review.googlesource.com/31588
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Quentin Smith <quentin@golang.org>
2016-10-24 15:20:23 +00:00
Russ Cox 4c1995f95b reflect: document DeepEqual(nil map, empty non-nil map) behavior
Fixes #16531.

Change-Id: I41ec8123f2d3fbe063fd3b09a9366e69722793e5
Reviewed-on: https://go-review.googlesource.com/31355
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-19 13:33:50 +00:00
Russ Cox f2f8d58b92 reflect: update FieldByNameFunc comment
This was supposed to be in CL 31354
but was dropped due to a Git usage error.

For #16573.

Change-Id: I3d99087c8efc8cbc016c55e8365d0005f79d1b2f
Reviewed-on: https://go-review.googlesource.com/31461
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-19 13:32:51 +00:00
Russ Cox e05d014048 reflect: correct Type.FieldByNameFunc docs
Fixes #16573.

Change-Id: I5a26eaa8b258cb1861190f9690086725532b8a0d
Reviewed-on: https://go-review.googlesource.com/31354
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-10-19 01:48:40 +00:00
Austin Clements d5bd797ee5 runtime: fix getArgInfo for deferred reflection calls
getArgInfo for reflect.makeFuncStub and reflect.methodValueCall is
necessarily special. These have dynamically determined argument maps
that are stored in their context (that is, their *funcval). These
functions are written to store this context at 0(SP) when called, and
getArgInfo retrieves it from there.

This technique works if getArgInfo is passed an active call frame for
one of these functions. However, getArgInfo is also used in
tracebackdefers, where the "call" is not a true call with an active
stack frame, but a deferred call. In this situation, getArgInfo
currently crashes because tracebackdefers passes a frame with sp set
to 0. However, the entire approach used by getArgInfo is flawed in
this situation because the wrapper has not actually executed, and
hence hasn't saved this metadata to any stack frame.

In the defer case, we know the *funcval from the _defer itself, so we
can fix this by teaching getArgInfo to use the *funcval context
directly when its available, and otherwise get it from the active call
frame.

While we're here, this commit simplifies getArgInfo a bit by making it
play more nicely with the type system. Rather than decoding the
*reflect.methodValue that is the wrapper's context as a *[2]uintptr,
just write out a copy of the reflect.methodValue type in the runtime.

Fixes #16331. Fixes #17471.

Change-Id: I81db4d985179b4a81c68c490cceeccbfc675456a
Reviewed-on: https://go-review.googlesource.com/31138
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-17 18:57:01 +00:00
Robert Griesemer ddb77100a6 reflect: ignore struct tags when converting structs
Implementation of spec change https://golang.org/cl/24190/.

For #16085.

Change-Id: Ib7cb513354269282dfad663c7d2c6e624149f3cd
Reviewed-on: https://go-review.googlesource.com/30191
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-10-04 17:15:59 +00:00
Brad Fitzpatrick ca04091f5b reflect: add Swapper func
Swapper returns a func that swaps two elements in a slice.

Updates #16721

Change-Id: I7f2287a675c10a05019e02b7d62fb870af31216f
Reviewed-on: https://go-review.googlesource.com/30088
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-09-30 20:26:54 +00:00
Michael Munday 3436f0776f reflect, runtime: optimize Value.Call on s390x and add benchmark
Use an MVC loop to copy arguments in runtime.call* rather than copying
bytes individually.

I've added the benchmark CallArgCopy to test the speed of Value.Call
for various argument sizes.

name                    old speed      new speed       delta
CallArgCopy/size=128     439MB/s ± 1%    582MB/s ± 1%   +32.41%  (p=0.000 n=10+10)
CallArgCopy/size=256     695MB/s ± 1%   1172MB/s ± 1%   +68.67%  (p=0.000 n=10+10)
CallArgCopy/size=1024    573MB/s ± 8%   4175MB/s ± 2%  +628.11%  (p=0.000 n=10+10)
CallArgCopy/size=4096   1.46GB/s ± 2%  10.19GB/s ± 1%  +600.52%  (p=0.000 n=10+10)
CallArgCopy/size=65536  1.51GB/s ± 0%  12.30GB/s ± 1%  +716.30%   (p=0.000 n=9+10)

Change-Id: I87dae4809330e7964f6cb4a9e40e5b3254dd519d
Reviewed-on: https://go-review.googlesource.com/28096
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bill O'Farrell <billotosyr@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-27 16:00:19 +00:00
Tormod Erevik Lea f2f374d125 reflect: update location of vet tool in comment
Change-Id: Ic5160edbbca4a8ffc7c7e6246e34fae1978470fd
Reviewed-on: https://go-review.googlesource.com/28912
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-09 15:02:46 +00:00
Matthew Dempsky be23e98e06 reflect: cleanup wording for type identity/equality
Use terms like "equal" and "identical types" to match the Go spec,
rather than inventing a new explanation. See also discussion on
golang.org/cl/27170.

Updates #16348.

Change-Id: I0fe0bd01c0d1da3c8937a579c2ba44cf1eb16b71
Reviewed-on: https://go-review.googlesource.com/28054
Reviewed-by: Rob Pike <r@golang.org>
2016-08-30 22:40:52 +00:00
Dave Cheney adb1e67f02 reflect: avoid zeroing memory that will be overwritten
Avoid new'ing memory that will be overwritten by assignment.

name              old time/op    new time/op    delta
Call-4               160ns ± 4%     155ns ± 2%  -3.19%        (p=0.003 n=10+10)
FieldByName1-4      94.5ns ± 2%    95.2ns ± 1%  +0.65%          (p=0.026 n=9+9)
FieldByName2-4      3.09µs ± 4%    3.13µs ± 2%    ~           (p=0.165 n=10+10)
FieldByName3-4      19.8µs ± 1%    19.9µs ± 1%    ~            (p=0.395 n=10+8)
InterfaceBig-4      11.6ns ± 0%    11.7ns ± 0%  +0.86%          (p=0.000 n=8+9)
InterfaceSmall-4    11.7ns ± 0%    11.7ns ± 0%    ~     (all samples are equal)
New-4               26.6ns ± 0%    26.4ns ± 0%  -0.64%         (p=0.000 n=10+9)

name              old alloc/op   new alloc/op   delta
Call-4              0.00B ±NaN%    0.00B ±NaN%    ~     (all samples are equal)

name              old allocs/op  new allocs/op  delta
Call-4               0.00 ±NaN%     0.00 ±NaN%    ~     (all samples are equal)

Change-Id: I12c85d4e65245598669dd6f66beb0744ec9b9d6d
Reviewed-on: https://go-review.googlesource.com/28011
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-30 08:08:37 +00:00
Ross Light ec75230b55 reflect: document equality guarantee for Type
The only previous mention of this property was in the String() method.
Since this is the only way to uniquely identify a type and we can't
change this property without breaking the Go 1 guarantee, it seems
better to document this property than hiding it on a method.

Fixes #16348

Change-Id: I3d25f7d6e6007e3c15c2e13010869888d0181fc2
Reviewed-on: https://go-review.googlesource.com/27170
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-08-23 23:20:48 +00:00
David Crawshaw 56752eb2b8 reflect: clear tflag on new types
Fixes #16722

Change-Id: I50a0e69d3e79d13bc1860cd983267c3db087a4b8
Reviewed-on: https://go-review.googlesource.com/27119
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-16 16:58:15 +00:00
Ian Lance Taylor 1f4e68d92b reflect: an unnamed type has no PkgPath
The reflect package was returning a non-empty PkgPath for an unnamed
type with methods, such as a type whose methods have a pointer
receiver.

Fixes #16328.

Change-Id: I733e93981ebb5c5c108ef9b03bf5494930b93cf3
Reviewed-on: https://go-review.googlesource.com/24862
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-07-12 12:43:48 +00:00
David Crawshaw ed9362f769 reflect, runtime: optimize Name method
Several minor changes that remove a good chunk of the overhead added
to the reflect Name method over the 1.7 cycle, as seen from the
non-SSA architectures.

In particular, there are ~20 fewer instructions in reflect.name.name
on 386, and the method now qualifies for inlining.

The simple JSON decoding benchmark on darwin/386:

	name           old time/op    new time/op    delta
	CodeDecoder-8    49.2ms ± 0%    48.9ms ± 1%  -0.77%  (p=0.000 n=10+9)

	name           old speed      new speed      delta
	CodeDecoder-8  39.4MB/s ± 0%  39.7MB/s ± 1%  +0.77%  (p=0.000 n=10+9)

On darwin/amd64 the effect is less pronounced:

	name           old time/op    new time/op    delta
	CodeDecoder-8    38.9ms ± 0%    38.7ms ± 1%  -0.38%  (p=0.005 n=10+10)

	name           old speed      new speed      delta
	CodeDecoder-8  49.9MB/s ± 0%  50.1MB/s ± 1%  +0.38%  (p=0.006 n=10+10)

Counterintuitively, I get much more useful benchmark data out of my
MacBook Pro than a linux workstation with more expensive Intel chips.
While the laptop has fewer cores and an active GUI, the single-threaded
performance is significantly better (nearly 1.5x decoding throughput)
so the differences are more pronounced.

For #16117.

Change-Id: I4e0cc1cc2d271d47d5127b1ee1ca926faf34cabf
Reviewed-on: https://go-review.googlesource.com/24510
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-06-28 12:28:05 +00:00
David Crawshaw 797dc58457 cmd/compile, etc: use tflag to optimize Name()==""
Improves JSON decoding benchmark:

	name                  old time/op    new time/op    delta
	CodeDecoder-8           41.3ms ± 6%    39.8ms ± 1%  -3.61%  (p=0.000 n=10+10)

	name                  old speed      new speed      delta
	CodeDecoder-8         47.0MB/s ± 6%  48.7MB/s ± 1%  +3.66%  (p=0.000 n=10+10)

Change-Id: I524ee05c432fad5252e79b29222ec635c1dee4b4
Reviewed-on: https://go-review.googlesource.com/24452
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-24 20:05:34 +00:00
David Crawshaw 3c6ed76da2 reflect: avoid lock for some NumMethod()==0 cases
The encoding/json package uses NumMethod()==0 as a fast check for
interface satisfaction. In the case when a type has no methods at
all, we don't need to grab the RWMutex.

Improves JSON decoding benchmark on linux/amd64:

	name           old time/op    new time/op    delta
	CodeDecoder-8    44.2ms ± 2%    40.6ms ± 1%  -8.11%  (p=0.000 n=10+10)

	name           old speed      new speed      delta
	CodeDecoder-8  43.9MB/s ± 2%  47.8MB/s ± 1%  +8.82%  (p=0.000 n=10+10)

For #16117

Change-Id: Id717e7fcd2f41b7d51d50c26ac167af45bae3747
Reviewed-on: https://go-review.googlesource.com/24433
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-24 18:01:08 +00:00
David Crawshaw e75c899a10 reflect: optimize (reflect.Type).Name
Improves JSON decoding on linux/amd64.

name                   old time/op    new time/op    delta
CodeUnmarshal-40         89.3ms ± 2%    86.3ms ± 2%  -3.31%  (p=0.000 n=22+22)

name                   old speed      new speed      delta
CodeUnmarshal-40       21.7MB/s ± 2%  22.5MB/s ± 2%  +3.44%  (p=0.000 n=22+22)

Updates #16117

Change-Id: I52acf31d7729400cfe6693e46292d41e1addba3d
Reviewed-on: https://go-review.googlesource.com/24410
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-06-23 18:19:52 +00:00
David Crawshaw e369490fb7 cmd/compile, etc: bring back ptrToThis
This was removed in CL 19695 but it slows down reflect.New, which ends
up on the hot path of things like JSON decoding.

There is no immediate cost in binary size, but it will make it harder to
further shrink run time type information in Go 1.8.

Before

	BenchmarkNew-40         30000000                36.3 ns/op

After

	BenchmarkNew-40         50000000                29.5 ns/op

Fixes #16161
Updates #16117

Change-Id: If7cb7f3e745d44678f3f5cf3a5338c59847529d2
Reviewed-on: https://go-review.googlesource.com/24400
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-06-23 17:39:38 +00:00
David Crawshaw af0fc83985 cmd/compile, etc: handle many struct fields
This adds 8 bytes of binary size to every type that has methods. It is
the smallest change I could come up with for 1.7.

Fixes #16037

Change-Id: Ibe15c3165854a21768596967757864b880dbfeed
Reviewed-on: https://go-review.googlesource.com/24070
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-14 15:32:34 +00:00
David Crawshaw 4b64c53c03 reflect: clear tflag for StructOf type
Fixes #15923

Change-Id: I3e56564365086ceb0bfc15db61db6fb446ab7448
Reviewed-on: https://go-review.googlesource.com/23760
Reviewed-by: Sebastien Binet <seb.binet@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-03 19:01:03 +00:00
Sebastien Binet 905ced0e6a reflect: document StructOf embedded fields limitation
This CL documents that StructOf currently does not generate wrapper
methods for embedded fields.

Updates #15924

Change-Id: I932011b1491d68767709559f515f699c04ce70d4
Reviewed-on: https://go-review.googlesource.com/23681
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-06-02 14:29:03 +00:00
David Crawshaw 56e5e0b69c runtime: tell race detector about reflectOffs.lock
Fixes #15832

Change-Id: I6f3f45e3c21edd0e093ecb1d8a067907863478f5
Reviewed-on: https://go-review.googlesource.com/23441
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2016-05-26 14:43:27 +00:00
David Crawshaw 9f38796270 reflect: remove type info for unexported methods
Also remove some of the now unnecessary corner case handling and
tests I've been adding recently for unexported method data.

For #15673

Change-Id: Ie0c7b03f2370bbe8508cdc5be765028f08000bd7
Reviewed-on: https://go-review.googlesource.com/23410
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-25 12:15:32 +00:00
David Crawshaw be1b930653 reflect: hide unexported methods that do not satisfy interfaces
Fixes #15673

Change-Id: Ib36d8db3299a93d92665dbde012d52c2c5332ac0
Reviewed-on: https://go-review.googlesource.com/23253
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-20 14:36:14 +00:00
Colin Cross 9d36cac99c reflect: remove out of date UTF-8 StructOf restriction
The initial implementation of reflect.StructOf in
https://golang.org/cl/9251 had a limitation that field names had to be
ASCII, which was later lifted by https://golang.org/cl/21777.  Remove
the out-of-date documentation disallowing UTF-8 field names.

Updates: #5748
Updates: #15064

Change-Id: I2c5bfea46bfd682449c6e847fc972a1a131f51b7
Reviewed-on: https://go-review.googlesource.com/23170
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-05-17 21:15:46 +00:00
David Crawshaw 0cc710dca6 reflect: fix method type string
By picking up a spurious tFlagExtraStar, the method type was printing
as unc instead of func.

Updates #15673

Change-Id: I0c2c189b99bdd4caeb393693be7520b8e3f342bf
Reviewed-on: https://go-review.googlesource.com/23103
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-13 17:44:48 +00:00
Aliaksandr Valialkin a71584975d reflect: fix vet warnings
Updated #11041

Change-Id: I4a110ba8fefb367a1049b4a65dd20c39eb890ea2
Reviewed-on: https://go-review.googlesource.com/23080
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-12 15:58:28 +00:00
Emmanuel Odeke 9edb27e76f reflect: make Field panic when out of bounds, as documented
Fixes #15046.

Change-Id: Iba7216297735be8e1ec550ce5336d17dcd3fd6b7
Reviewed-on: https://go-review.googlesource.com/22992
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-10 15:16:33 +00:00
Austin Clements a20fd1f6ba runtime: reclaim scan/dead bit in first word
With the switch to separate mark bitmaps, the scan/dead bit for the
first word of each object is now unused. Reclaim this bit and use it
as a scan/dead bit, just like words three and on. The second word is
still used for checkmark.

This dramatically simplifies heapBitsSetTypeNoScan and hasPointers,
since they no longer need different cases for 1, 2, and 3+ word
objects. They can instead just manipulate the heap bitmap for the
first word and be done with it.

In order to enable this, we change heapBitsSetType and runGCProg to
always set the scan/dead bit to scan for the first word on every code
path. Since these functions only apply to types that have pointers,
there's no need to do this conditionally: it's *always* necessary to
set the scan bit in the first word.

We also change every place that scans an object and checks if there
are more pointers. Rather than only checking morePointers if the word
is >= 2, we now check morePointers if word != 1 (since that's the
checkmark word).

Looking forward, we should probably reclaim the checkmark bit, too,
but that's going to be quite a bit more work.

Tested by setting doubleCheck in heapBitsSetType and running all.bash
on both linux/amd64 and linux/386, and by running GOGC=10 all.bash.

This particularly improves the FmtFprintf* go1 benchmarks, since they
do a large amount of noscan allocation.

name                      old time/op    new time/op    delta
BinaryTree17-12              2.34s ± 1%     2.38s ± 1%  +1.70%  (p=0.000 n=17+19)
Fannkuch11-12                2.09s ± 0%     2.09s ± 1%    ~     (p=0.276 n=17+16)
FmtFprintfEmpty-12          44.9ns ± 2%    44.8ns ± 2%    ~     (p=0.340 n=19+18)
FmtFprintfString-12          127ns ± 0%     125ns ± 0%  -1.57%  (p=0.000 n=16+15)
FmtFprintfInt-12             128ns ± 0%     122ns ± 1%  -4.45%  (p=0.000 n=15+20)
FmtFprintfIntInt-12          207ns ± 1%     193ns ± 0%  -6.55%  (p=0.000 n=19+14)
FmtFprintfPrefixedInt-12     197ns ± 1%     191ns ± 0%  -2.93%  (p=0.000 n=17+18)
FmtFprintfFloat-12           263ns ± 0%     248ns ± 1%  -5.88%  (p=0.000 n=15+19)
FmtManyArgs-12               794ns ± 0%     779ns ± 1%  -1.90%  (p=0.000 n=18+18)
GobDecode-12                7.14ms ± 2%    7.11ms ± 1%    ~     (p=0.072 n=20+20)
GobEncode-12                5.85ms ± 1%    5.82ms ± 1%  -0.49%  (p=0.000 n=20+20)
Gzip-12                      218ms ± 1%     215ms ± 1%  -1.22%  (p=0.000 n=19+19)
Gunzip-12                   36.8ms ± 0%    36.7ms ± 0%  -0.18%  (p=0.006 n=18+20)
HTTPClientServer-12         77.1µs ± 4%    77.1µs ± 3%    ~     (p=0.945 n=19+20)
JSONEncode-12               15.6ms ± 1%    15.9ms ± 1%  +1.68%  (p=0.000 n=18+20)
JSONDecode-12               55.2ms ± 1%    53.6ms ± 1%  -2.93%  (p=0.000 n=17+19)
Mandelbrot200-12            4.05ms ± 1%    4.05ms ± 0%    ~     (p=0.306 n=17+17)
GoParse-12                  3.14ms ± 1%    3.10ms ± 1%  -1.31%  (p=0.000 n=19+18)
RegexpMatchEasy0_32-12      69.3ns ± 1%    70.0ns ± 0%  +0.89%  (p=0.000 n=19+17)
RegexpMatchEasy0_1K-12       237ns ± 1%     236ns ± 0%  -0.62%  (p=0.000 n=19+16)
RegexpMatchEasy1_32-12      69.5ns ± 1%    70.3ns ± 1%  +1.14%  (p=0.000 n=18+17)
RegexpMatchEasy1_1K-12       377ns ± 1%     366ns ± 1%  -3.03%  (p=0.000 n=15+19)
RegexpMatchMedium_32-12      107ns ± 1%     107ns ± 2%    ~     (p=0.318 n=20+19)
RegexpMatchMedium_1K-12     33.8µs ± 3%    33.5µs ± 1%  -1.04%  (p=0.001 n=20+19)
RegexpMatchHard_32-12       1.68µs ± 1%    1.73µs ± 0%  +2.50%  (p=0.000 n=20+18)
RegexpMatchHard_1K-12       50.8µs ± 1%    52.0µs ± 1%  +2.50%  (p=0.000 n=19+18)
Revcomp-12                   381ms ± 1%     385ms ± 1%  +1.00%  (p=0.000 n=17+18)
Template-12                 64.9ms ± 3%    62.6ms ± 1%  -3.55%  (p=0.000 n=19+18)
TimeParse-12                 324ns ± 0%     328ns ± 1%  +1.25%  (p=0.000 n=18+18)
TimeFormat-12                345ns ± 0%     334ns ± 0%  -3.31%  (p=0.000 n=15+17)
[Geo mean]                  52.1µs         51.5µs       -1.00%

Change-Id: I13e74da3193a7f80794c654f944d1f0d60817049
Reviewed-on: https://go-review.googlesource.com/22632
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-30 16:49:54 +00:00
David Crawshaw bddfc337f9 reflect: fix strings of SliceOf-created types
The new type was inheriting the tflagExtraStar from its prototype.

Fixes #15467

Change-Id: Ic22c2a55cee7580cb59228d52b97e1c0a1e60220
Reviewed-on: https://go-review.googlesource.com/22501
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2016-04-27 18:07:24 +00:00
David Crawshaw 217be5b35d reflect: unnamed interface types have no name
Fixes #15468

Change-Id: I8723171f87774a98d5e80e7832ebb96dd1fbea74
Reviewed-on: https://go-review.googlesource.com/22524
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
2016-04-27 18:06:20 +00:00
David Crawshaw 96b8f70e22 cmd/link: correctly decode name length
The linker was incorrectly decoding type name lengths, causing
typelinks to be sorted out of order and in cases where the name was
the exact right length, linker panics.

Added a test to the reflect package that causes TestTypelinksSorted
to fail before this CL. It's not the exact failure seen in #15448
but it has the same cause: decodetype_name calculating the wrong
length.

The equivalent decoders in reflect/type.go and runtime/type.go
have the parenthesis in the right place.

Fixes #15448

Change-Id: I33257633d812b7d2091393cb9d6cc8a73e0138c8
Reviewed-on: https://go-review.googlesource.com/22403
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-26 15:55:06 +00:00
David Crawshaw c165988360 cmd/compile, etc: use nameOff in uncommonType
linux/amd64 PIE:
	cmd/go:  -62KB (0.5%)
	jujud:  -550KB (0.7%)

For #6853.

Change-Id: Ieb67982abce5832e24b997506f0ae7108f747108
Reviewed-on: https://go-review.googlesource.com/22371
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-04-22 13:51:29 +00:00
David Crawshaw 1492e7db05 cmd/compile, etc: use nameOff for rtype string
linux/amd64:
	cmd/go:   -8KB (basically nothing)

linux/amd64 PIE:
	cmd/go: -191KB (1.6%)
	jujud:  -1.5MB (1.9%)

Updates #6853
Fixes #15064

Change-Id: I0adbb95685e28be92e8548741df0e11daa0a9b5f
Reviewed-on: https://go-review.googlesource.com/21777
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-04-22 10:08:05 +00:00
David Crawshaw 2e2df78ae9 reflect: test that method name offset is valid
Bug fix went in CL 21396, this is a matching test.

Fixes #15343

Change-Id: I3670145c7cac45cb4fb3121ffc039cfb7fa7c87a
Reviewed-on: https://go-review.googlesource.com/22171
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-04-18 19:13:36 +00:00
David Crawshaw 95df0c6ab9 cmd/compile, etc: use name offset in method tables
Introduce and start using nameOff for two encoded names. This pair
of changes is best done together because the linker's method decoder
expects the method layouts to match.

Precursor to converting all existing name and *string fields to
nameOff.

linux/amd64:
	cmd/go:  -45KB (0.5%)
	jujud:  -389KB (0.6%)

linux/amd64 PIE:
	cmd/go: -170KB (1.4%)
	jujud:  -1.5MB (1.8%)

For #6853.

Change-Id: Ia044423f010fb987ce070b94c46a16fc78666ff6
Reviewed-on: https://go-review.googlesource.com/21396
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-04-18 09:12:41 +00:00
Matthew Dempsky 0da4dbe232 all: remove unnecessary type conversions
cmd and runtime were handled separately, and I'm intentionally skipped
syscall. This is the rest of the standard library.

CL generated mechanically with github.com/mdempsky/unconvert.

Change-Id: I9e0eff886974dedc37adb93f602064b83e469122
Reviewed-on: https://go-review.googlesource.com/22104
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-15 07:31:45 +00:00
David Crawshaw f120936dff cmd/compile, etc: use name for type pkgPath
By replacing the *string used to represent pkgPath with a
reflect.name everywhere, the embedded *string for package paths
inside the reflect.name can be replaced by an offset, nameOff.
This reduces the number of pointers in the type information.

This also moves all reflect.name types into the same section, making
it possible to use nameOff more widely in later CLs.

No significant binary size change for normal binaries, but:

linux/amd64 PIE:
	cmd/go: -440KB (3.7%)
	jujud:  -2.6MB (3.2%)

For #6853.

Change-Id: I3890b132a784a1090b1b72b32febfe0bea77eaee
Reviewed-on: https://go-review.googlesource.com/21395
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-04-13 20:48:26 +00:00
David Crawshaw 7d469179e6 cmd/compile, etc: store method tables as offsets
This CL introduces the typeOff type and a lookup method of the same
name that can turn a typeOff offset into an *rtype.

In a typical Go binary (built with buildmode=exe, pie, c-archive, or
c-shared), there is one moduledata and all typeOff values are offsets
relative to firstmoduledata.types. This makes computing the pointer
cheap in typical programs.

With buildmode=shared (and one day, buildmode=plugin) there are
multiple modules whose relative offset is determined at runtime.
We identify a type in the general case by the pair of the original
*rtype that references it and its typeOff value. We determine
the module from the original pointer, and then use the typeOff from
there to compute the final *rtype.

To ensure there is only one *rtype representing each type, the
runtime initializes a typemap for each module, using any identical
type from an earlier module when resolving that offset. This means
that types computed from an offset match the type mapped by the
pointer dynamic relocations.

A series of followup CLs will replace other *rtype values with typeOff
(and name/*string with nameOff).

For types created at runtime by reflect, type offsets are treated as
global IDs and reference into a reflect offset map kept by the runtime.

darwin/amd64:
	cmd/go:  -57KB (0.6%)
	jujud:  -557KB (0.8%)

linux/amd64 PIE:
	cmd/go: -361KB (3.0%)
	jujud:  -3.5MB (4.2%)

For #6853.

Change-Id: Icf096fd884a0a0cb9f280f46f7a26c70a9006c96
Reviewed-on: https://go-review.googlesource.com/21285
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-13 13:03:11 +00:00
Ian Lance Taylor 982274c96d reflect: test that Call results are not addressable
Gccgo was erroneously marking Call results as addressable, which led to
an obscure bug using text/template, as text/template calls CanAddr to
check whether to take the address of a value when looking up methods.
When a function returned a pointer, and CanAddr was true, the result was
a pointer to a pointer that had no methods.

Fixed in gccgo by https://golang.org/cl/21908.  Adding the test here so
that it doesn't regress.

Change-Id: I1d25b868e1b8e2348b21cbac6404a636376d1a4a
Reviewed-on: https://go-review.googlesource.com/21930
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-12 23:14:16 +00:00
David Crawshaw f028b9f9e2 cmd/link, etc: store typelinks as offsets
This is the first in a series of CLs to replace the use of pointers
in binary read-only data with offsets.

In standard Go binaries these CLs have a small effect, shrinking
8-byte pointers to 4-bytes. In position-independent code, it also
saves the dynamic relocation for the pointer. This has a significant
effect on the binary size when building as PIE, c-archive, or
c-shared.

darwin/amd64:
	cmd/go: -12KB (0.1%)
	jujud:  -82KB (0.1%)

linux/amd64 PIE:
	cmd/go:  -86KB (0.7%)
	jujud:  -569KB (0.7%)

For #6853.

Change-Id: Iad5625bbeba58dabfd4d334dbee3fcbfe04b2dcf
Reviewed-on: https://go-review.googlesource.com/21284
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-12 20:32:41 +00:00
Michael Munday db9348b866 reflect: add s390x support
Change-Id: I1f975130179cf26af67e82664310b93d43e87a75
Reviewed-on: https://go-review.googlesource.com/20944
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-06 04:23:06 +00:00
Sebastien Binet 633ab7426a reflect: implement StructOf
This change exposes a facility to create new struct types from a slice of
reflect.StructFields.

- reflect: first stab at implementing StructOf
- reflect: tests for StructOf

StructOf creates new struct types in the form of structTypeWithMethods
to accomodate the GC (especially the uncommonType.methods slice field.)

Creating struct types with embedded interfaces with unexported methods
is not supported yet and will panic.
Creating struct types with non-ASCII field names or types is not yet
supported (see #15064.)

Binaries' sizes for linux_amd64:

old=tip (0104a31)

            old bytes     new bytes     delta
bin/go      9911336       9915456       +0.04%
reflect     781704        830048        +6.18%

Updates #5748.
Updates #15064.

Change-Id: I3b8fd4fadd6ce3b1b922e284f0ae72a3a8e3ce44
Reviewed-on: https://go-review.googlesource.com/9251
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
2016-04-01 14:56:21 +00:00
David Crawshaw 43a274fd67 cmd/compile: include pkgPath on all struct types
Fixes #15026.

Change-Id: I61ed71152b99973270d79264d1e8f466f7343c02
Reviewed-on: https://go-review.googlesource.com/21286
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-31 20:11:39 +00:00
David Crawshaw 640164bc1c reflect: test name data is aligned
For #14962.

Change-Id: I3539d882487c99dee99ac953e039b79c6b963cf9
Reviewed-on: https://go-review.googlesource.com/21150
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-25 20:37:08 +00:00
David Crawshaw 8cb74e1d18 reflect: name interface type that pins method info
I recently added TestUnexportedMethods which uses an interface type
to pin type information for an unexported method. But as written,
the interface type is not accessible to the reflect package.

You can imagine a future compiler optimization realizing that and
removing the type information for f. In fact, cl/20901 happens to
do that.

Change-Id: I1ddb67f50cb9b5737253b58f10545f3de652c29d
Reviewed-on: https://go-review.googlesource.com/21112
Reviewed-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-25 17:19:03 +00:00
Dominik Honnef fdba5a7544 all: delete dead non-test code
This change removes a lot of dead code. Some of the code has never been
used, not even when it was first commited. The rest shouldn't have
survived refactors.

This change doesn't remove unused routines helpful for debugging, nor
does it remove code that's used in commented out blocks of code that are
only unused temporarily. Furthermore, unused constants weren't removed
when they were part of a set of constants from specifications.

One noteworthy omission from this CL are about 1000 lines of unused code
in cmd/fix, 700 lines of which are the typechecker, which hasn't been
used ever since the pre-Go 1 fixes have been removed. I wasn't sure if
this code should stick around for future uses of cmd/fix or be culled as
well.

Change-Id: Ib714bc7e487edc11ad23ba1c3222d1fd02e4a549
Reviewed-on: https://go-review.googlesource.com/20926
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-25 06:28:13 +00:00
John Jeffery 5c8674a497 reflect: add method StructTag.Lookup
The Lookup method provides a way to extract a tag value, while
determining whether the tag key exists in the struct field's tag.

Fixes #14883

Change-Id: I7460cb68f0ca1aaa025935050b9e182efcb64db3
Reviewed-on: https://go-review.googlesource.com/20864
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-25 04:54:19 +00:00
David Crawshaw 24ce64d1a9 cmd/compile, runtime: new static name encoding
Create a byte encoding designed for static Go names.

It is intended to be a compact representation of a name
and optional tag data that can be turned into a Go string
without allocating, and describes whether or not it is
exported without unicode table.

The encoding is described in reflect/type.go:

// The first byte is a bit field containing:
//
//	1<<0 the name is exported
//	1<<1 tag data follows the name
//	1<<2 pkgPath *string follow the name and tag
//
// The next two bytes are the data length:
//
//	 l := uint16(data[1])<<8 | uint16(data[2])
//
// Bytes [3:3+l] are the string data.
//
// If tag data follows then bytes 3+l and 3+l+1 are the tag length,
// with the data following.
//
// If the import path follows, then ptrSize bytes at the end of
// the data form a *string. The import path is only set for concrete
// methods that are defined in a different package than their type.

Shrinks binary sizes:

	cmd/go: 164KB (1.6%)
	jujud:  1.0MB (1.5%)

For #6853.

Change-Id: I46b6591015b17936a443c9efb5009de8dfe8b609
Reviewed-on: https://go-review.googlesource.com/20968
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-25 00:13:49 +00:00
David Crawshaw 44d3f89e99 cmd/link, reflect: remove some method type data
Remove reflect type information for unexported methods that do not
satisfy any interface in the program.

Ideally the unexported method would not appear in the method list at
all, but that is tricky because the slice is built by the compiler.

Reduces binary size:

	cmd/go: 81KB (0.8%)
	jujud: 258KB (0.4%)

For #6853.

Change-Id: I25ef8df6907e9ac03b18689d584ea46e7d773043
Reviewed-on: https://go-review.googlesource.com/21033
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-23 17:00:43 +00:00
Dominik Honnef b2cf571040 all: delete dead test code
This deletes unused code and helpers from tests.

Change-Id: Ie31d46115f558ceb8da6efbf90c3c204e03b0d7e
Reviewed-on: https://go-review.googlesource.com/20927
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-21 07:10:08 +00:00
David Crawshaw f2772a4935 cmd/compile: compute second method type at runtime
The type information for a method includes two variants: a func
without the receiver, and a func with the receiver as the first
parameter. The former is used as part of the dynamic interface
checks, but the latter is only returned as a type in the
reflect.Method struct.

Instead of computing it at compile time, construct it at run time
with reflect.FuncOf.

Using cl/20701 as a baseline,

	cmd/go: -480KB, (4.4%)
	jujud:  -5.6MB, (7.8%)

For #6853.

Change-Id: I1b8c73f3ab894735f53d00cb9c0b506d84d54e92
Reviewed-on: https://go-review.googlesource.com/20709
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-15 19:57:40 +00:00
Dominik Honnef 368507bb6f reflect: use SelectDir instead of uintptr in runtimeSelect
And fix the wrong comment.

Initially found this because the comment was wrong about the possible
values. Then noticed that there doesn't seem to be any reason to use
uintptr over SelectDir.

Change-Id: I4f9f9640e49d89e558ed00bd99e57dab890785f5
Reviewed-on: https://go-review.googlesource.com/20655
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-14 01:55:31 +00:00
David Crawshaw 7c546566c3 cmd/compile: compute number of arguments correctly
The outCount value includes a flag bit for dotdotdot.

If we have this count incorrect, then the offset for the
methodset *rtype are in the wrong place.

Fixes #14783

Change-Id: If5acb16af08d4ffe36c8c9ee389c32f2712ce757
Reviewed-on: https://go-review.googlesource.com/20566
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-12 01:23:25 +00:00
David Crawshaw 8df733bd22 cmd/compile: remove slices from rtype.funcType
Alternative to golang.org/cl/19852. This memory layout doesn't have
an easy type representation, but it is noticeably smaller than the
current funcType, and saves significant extra space.

Some notes on the layout are in reflect/type.go:

// A *rtype for each in and out parameter is stored in an array that
// directly follows the funcType (and possibly its uncommonType). So
// a function type with one method, one input, and one output is:
//
//	struct {
//		funcType
//		uncommonType
//		[2]*rtype    // [0] is in, [1] is out
//		uncommonTypeSliceContents
//	}

There are three arbitrary limits introduced by this CL:

1. No more than 65535 function input parameters.
2. No more than 32767 function output parameters.
3. reflect.FuncOf is limited to 128 parameters.

I don't think these are limits in practice, but are worth noting.

Reduces godoc binary size by 2.4%, 330KB.

For #6853.

Change-Id: I225c0a0516ebdbe92d41dfdf43f716da42dfe347
Reviewed-on: https://go-review.googlesource.com/19916
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-09 01:25:18 +00:00
David Crawshaw a24b3ed753 cmd/compile: remove rtype *uncommonType field
Instead of a pointer on every rtype, use a bit flag to indicate that
the contents of uncommonType directly follows the rtype value when it
is needed.

This requires a bit of juggling in the compiler's rtype encoder. The
backing arrays for fields in the rtype are presently encoded directly
after the slice header. This packing requires separating the encoding
of the uncommonType slice headers from their backing arrays.

Reduces binary size of godoc by ~180KB (1.5%).
No measurable change in all.bash time.
For #6853.

Change-Id: I60205948ceb5c0abba76fdf619652da9c465a597
Reviewed-on: https://go-review.googlesource.com/19790
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-08 23:23:13 +00:00
David Crawshaw 69285a8b46 reflect: recognize unnamed directional channels
go test github.com/onsi/gomega/gbytes now passes at tip, and tests
added to the reflect package.

Fixes #14645

Change-Id: I16216c1a86211a1103d913237fe6bca5000cf885
Reviewed-on: https://go-review.googlesource.com/20221
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-04 20:34:30 +00:00
Brad Fitzpatrick 5fea2ccc77 all: single space after period.
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.

This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:

$ perl -i -npe 's,^(\s*// .+[a-z]\.)  +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.)  +([A-Z])')
$ go test go/doc -update

Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-02 00:13:47 +00:00
Brad Fitzpatrick 519474451a all: make copyright headers consistent with one space after period
This is a subset of https://golang.org/cl/20022 with only the copyright
header lines, so the next CL will be smaller and more reviewable.

Go policy has been single space after periods in comments for some time.

The copyright header template at:

    https://golang.org/doc/contribute.html#copyright

also uses a single space.

Make them all consistent.

Change-Id: Icc26c6b8495c3820da6b171ca96a74701b4a01b0
Reviewed-on: https://go-review.googlesource.com/20111
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-01 23:34:33 +00:00
David Crawshaw 0231f5420f cmd/compile: remove uncommonType.name
Reduces binary size of cmd/go by 0.5%.
For #6853.

Change-Id: I5a4b814049580ab5098ad252d979f80b70d8a5f9
Reviewed-on: https://go-review.googlesource.com/19694
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-26 12:02:39 +00:00
David Crawshaw 30f93f0994 cmd/compile: remove rtype.ptrToThis
Simplifies some code as ptrToThis was unreliable under dynamic
linking. Now the same type lookup is used regardless of execution
mode.

A synthetic relocation, R_USETYPE, is introduced to make sure the
linker includes *T on use of T, if *T is carrying methods.

Changes the heap dump format. Anything reading the format needs to
look at the last bool of a type of an interface value to determine
if the type should be the pointer-to type.

Reduces binary size of cmd/go by 0.2%.
For #6853.

Change-Id: I79fcb19a97402bdb0193f3c7f6d94ddf061ee7b2
Reviewed-on: https://go-review.googlesource.com/19695
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-25 17:47:42 +00:00
Martin Möhrmann fdd0179bb1 all: fix typos and spelling
Change-Id: Icd06d99c42b8299fd931c7da821e1f418684d913
Reviewed-on: https://go-review.googlesource.com/19829
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-24 18:42:29 +00:00
David Crawshaw a858931200 cmd/compile: embed type string header in rtype
Reduces binary size of cmd/go by 1%.

For #6853.

Change-Id: I6f2992a4dd3699db1b532ab08683e82741b9c2e4
Reviewed-on: https://go-review.googlesource.com/19692
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-24 17:12:15 +00:00
Matthew Dempsky 9877900c8c Revert "cmd/compile: move hiter, hmap, and scase definitions into builtin.go"
This reverts commit f28bbb776a.

Change-Id: I82fb81dcff3ddcaefef72949f1ef3a41bcd22301
Reviewed-on: https://go-review.googlesource.com/19849
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-02-23 19:42:52 +00:00
Matthew Dempsky f28bbb776a cmd/compile: move hiter, hmap, and scase definitions into builtin.go
Also eliminates per-maptype hiter and hmap types, since they're not
really needed anyway.  Update packages reflect and runtime
accordingly.

Reduces golang.org/x/tools/cmd/godoc's text segment by ~170kB:

   text	   data	    bss	    dec	    hex	filename
13085702	 140640	 151520	13377862	 cc2146	godoc.before
12915382	 140640	 151520	13207542	 c987f6	godoc.after

Updates #6853.

Change-Id: I948b2bc1f22d477c1756204996b4e3e1fb568d81
Reviewed-on: https://go-review.googlesource.com/16610
Reviewed-by: Keith Randall <khr@golang.org>
2016-02-22 07:42:37 +00:00
Russ Cox a77182f47f reflect: document DeepEqual, fix case of maps with NaN keys
The meaning of DeepEqual has never been specified.
Do that.

Also fix bug involving maps with NaN keys.

Except for the map bug fix, there should be no semantic changes here.

Fixes #12025.

Change-Id: Ied562cf543a22ec645d42bdb9b41d451c16b1f21
Reviewed-on: https://go-review.googlesource.com/17450
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
2015-12-11 05:50:05 +00:00
Keith Randall 8d31a86a1e reflect: mark mapassign as noescape
The lack of this annotation causes Value.SetMapIndex to allocate
when it doesn't need to.

Add comments about why it's safe to do so.

Add a test to make sure we stay allocation-free.

Change-Id: I00826e0d73e317a31bdeae5c7e46bf95b0c6ae6a
Reviewed-on: https://go-review.googlesource.com/17060
Reviewed-by: David Chase <drchase@google.com>
2015-11-19 21:35:58 +00:00
Yao Zhang 559fb85af6 reflect: added support for mips64{,le}
Change-Id: I84ced3734410d3d05f195901f44d33f4ae6036b1
Reviewed-on: https://go-review.googlesource.com/14452
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-11-12 04:50:18 +00:00
kargakis e243d242d7 reflect: Comment fix
Change-Id: I86cdd5c1d7b6f76d3474d180e75ea0c732241080
Reviewed-on: https://go-review.googlesource.com/16309
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-10-27 15:46:29 +00:00
Marcel van Lohuizen afe9837b23 cmd/compile/internal/gc: make embedded unexported structs RO
gc will need to be rebuild.

Package that assume f.PkgPath != nil means a field is unexported and
must be ignored must be revised to check for
	f.PkgPath != nil && !f.Anonymous,
so that they do try to walk into the embedded fields to look for
exported fields contained within.

Closes #12367, fixes #7363, fixes #11007, and fixes #7247.

Change-Id: I16402ee21ccfede80f277f84b3995cf26e97433d
Reviewed-on: https://go-review.googlesource.com/14085
Reviewed-by: Russ Cox <rsc@golang.org>
2015-10-26 13:57:48 +00:00
Marcel van Lohuizen adf9b30e55 reflect: adjust access to unexported embedded structs
This CL changes reflect to allow access to exported fields and
methods in unexported embedded structs for gccgo and after gc
has been adjusted to disallow access to embedded unexported structs.

Adresses #12367, #7363, #11007, and #7247.

Change-Id: If80536eab35abcd25300d8ddc2d27d5c42d7e78e
Reviewed-on: https://go-review.googlesource.com/14010
Reviewed-by: Russ Cox <rsc@golang.org>
2015-10-26 10:14:38 +00:00
Michael Hudson-Doyle b8f8969fbd reflect, runtime, runtime/cgo: use ppc64 asm constant for fixed frame size
Shared libraries on ppc64le will require a larger minimum stack frame (because
the ABI mandates that the TOC pointer is available at 24(R1)). Part 3 of that
is using a #define in the ppc64 assembly to refer to the size of the fixed
part of the stack (finding all these took me about a week!).

Change-Id: I50f22fe1c47af1ec59da1bd7ea8f84a4750df9b7
Reviewed-on: https://go-review.googlesource.com/15525
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-10-18 23:15:26 +00:00