asmdecl:
- MOVW $x+0(FP) is OK if x is big, because $x is an address
  (happens in internal/cpu, golang.org/x/sys/cpu, runtime)
- ignore TEXT lines in comments
  (happens in runtime/internal/atomic)
- wasm's CallImport instruction writes return results
  (happens in syscall)
- allow write out-of-bounds (SP) references in NOFRAME functions
  (happens in runtime)
- recognize "NOP SP" as an SP "write" to disable SP bounds checking
- 'go test' in passes/asmdecl was not testing all architectures; fix that

stdmethods:
- ignore WriteTo if obviously not io.WriterTo (as in go/types and runtime/pprof)

errorsas:
- don't complain about package errors testing invalid calls

structtag:
- don't complain about encoding/json and encoding/xml testing invalid tags

unmarshal:
- don't complain about encoding/gob, encoding/json, encoding/xml testing invalid calls

For golang/go#31916.
Fixes golang/go#25822.

Change-Id: I322c08b5991ffc4995112b8ea945161a4c5193ce
Reviewed-on: https://go-review.googlesource.com/c/tools/+/176097
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

The vetall builder runs vet straight out of golang.org/x/tools,
so submiting CL 176097 in that repo will break the builder
by making all these whitelist entries stale.
Submiting this CL will fix it, by removing them.

The addition of the gcWriteBarrier declaration in runtime/stubs.go
is necessary because the diagnostic is no longer emitted on arm,
so it must be removed from all.txt. Adding it to runtime is better
than adding it to every-other-goarch.txt.

For #31916.

Change-Id: I432f6049cd3ee5a467add5066c440be8616d9d54
Reviewed-on: https://go-review.googlesource.com/c/go/+/176177
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Renaming the method makes clear, both to readers and to vet,
that this method is not the implementation of io.Seeker:
it cannot fail.

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

For #31916.

Change-Id: I3e6ad7264cb0121b4b76935450cccb71d533e96b
Reviewed-on: https://go-review.googlesource.com/c/go/+/176108
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Renaming the method makes clear, both to readers and to vet,
that this method is not the implementation of io.ByteWriter.

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

For #31916.

Change-Id: I79da062ca6469b62a6b9e284c6cf2413c7425249
Reviewed-on: https://go-review.googlesource.com/c/go/+/176109
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Renaming the method makes clear, both to readers and to vet,
that this method is not the implementation of io.ByteWriter.

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

For #31916.

Change-Id: I5b509eb7f0118d5f2d3c6e352ff2849cd5a3071e
Reviewed-on: https://go-review.googlesource.com/c/go/+/176110
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

These ridiculous tags are testing what happens with very long tags.
There is no need for them to be malformed as well.
Fix them to make vet happier.

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

For #31916.

Change-Id: I100aed5230fcde41676c79c7074c69c16ea4b96d
Reviewed-on: https://go-review.googlesource.com/c/go/+/176111
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "GOOS=linux GOARCH=386 go vet -unsafeptr=false runtime" happy,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I3e5586a7ff6e359357350d0602c2259493280ded
Reviewed-on: https://go-review.googlesource.com/c/go/+/176099
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "GOOS=linux GOARCH=amd64 go vet -unsafeptr=false runtime" happy,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I4ca1acb02f4666b102d25fcc55fac96b8f80379a
Reviewed-on: https://go-review.googlesource.com/c/go/+/176100
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "GOOS=linux GOARCH=arm go vet -unsafeptr=false runtime" happy,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: Ifae75b832320b5356ac8773cf85055bfb2bd7214
Reviewed-on: https://go-review.googlesource.com/c/go/+/176101
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

…*, linux/s390x

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for these GOOS/GOARCHes,
except for an unresolved complaint on mips/mipsle that is a bug in vet,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I6ef7e982a2fdbbfbc22cee876ca37ac54d8109e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/176102
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for these GOOS/GOARCHes,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: Ic64f7f4034695dd4c32c9b7f258960faf3742a83
Reviewed-on: https://go-review.googlesource.com/c/go/+/176103
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for these GOOSes,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: Id2e1223497bd0cd6e880cd81f3ece6363e58219f
Reviewed-on: https://go-review.googlesource.com/c/go/+/176104
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for these GOOSes,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I63c4805bdd44b301072da66c77086940e2a2765e
Reviewed-on: https://go-review.googlesource.com/c/go/+/176105
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for windows/*,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: If37ab2b3f6fca4696b8a6afb2ef11ba6c4fb42e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/176106
Reviewed-by: Austin Clements <austin@google.com>

Working toward making the tree vet-safe instead of having
so many exceptions in cmd/vet/all/whitelist.

This CL makes "go vet -unsafeptr=false runtime" happy for nacl/*,
while keeping "GO_BUILDER_NAME=misc-vetall go tool dist test" happy too.

For #31916.

Change-Id: I6adb4a7b0c2b03d901fba37f9c05e74e5b7b6691
Reviewed-on: https://go-review.googlesource.com/c/go/+/176107
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The new prototypes of duffzero and duffcopy must be
accompanied by functions. Otherwise buildmode=shared
(in particular, misc/cgo/testshared) has missing symbols.

The right fix, of course, is to implement these on s390x.

For #31916.

Change-Id: I3efff5e3011956341e1b26223a4847a8a91a0453
Reviewed-on: https://go-review.googlesource.com/c/go/+/176397
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

…yzers

Otherwise the specific set of gob registrations varies
according to the command line, which makes it impossible
for a narrow analysis run (for example, just one analyzer)
to read fact files written by less narrow runs (for example, all the analyzers).

This will start mattering in the standard repo vet.

For golang/go#31916.

Change-Id: I6fa90b3dfdf28ede6f995db3904211b6be68bb73
Reviewed-on: https://go-review.googlesource.com/c/tools/+/176357
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>

Updates golang/go#31916

Change-Id: I38c08955bdb4ff2b0963d5c91c6e8f78267b8004
Reviewed-on: https://go-review.googlesource.com/c/build/+/176599
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Vet needs export data for the imports of the package it is analyzing.
Vet does not need export data for the package itself, since vet will
do its own type checking. Assuming that vet is just as good as the compiler
at detecting invalid programs, don't run the compiler unnecessarily.

This especially matters for tests without external test files or for
which the external test files do not import the test-augmented original
package. In that case, the test-augmented original package need not
be compiled at all.

Cuts time for 'go clean -cache && go vet -x cmd/compile/internal/ssa'
from 7.6r 24.3u 2.8s to 3.5r 8.5u 1.9s, by not running the compiler
on the augmented test package.

There is still more to be done here - if we do need to build a
test-augmented package, we rerun cgo unnecessarily.
But this is a big help.

Cuts time for 'go vet std cmd' by about 30%.

For #31916.

Change-Id: If6136b4d384f1da77aed90b43f1a6b95f09b5d86
Reviewed-on: https://go-review.googlesource.com/c/go/+/176438
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Now that the main tree complies with 'go vet', enable all vet checks
during 'go test' in the main tree. This helps surface helpful errors
while developing, instead of having to wait for the misc-vet-vetall builder.

During 'go test', the additional vet checks are essentially free:
the vet invocations themselves take only 8 seconds total for the entire tree.

Also update buildall.bash (used by the misc-compile builders)
to run 'go vet std cmd' for each GOOS/GOARCH pair.
This is not as free, since in general it can require recompiling
packages with their tests included before invoking vet.
(That compilation was going on anyway in the 'go test' case.)

On my Mac laptop, ./buildall.bash freebsd used to take
68+16+17+18 = 119 seconds for make.bash and then
the builds of the three freebsd architectures.
Now it takes 68+16+23+17+23+18+24 = 189 seconds, 60% longer.
Some of this is spent doing unnecessary cgo work.
Still, this lets us shard the vet checks and match all.bash.

Fixes #20119.
For #31916.

Change-Id: I6b0c40bac47708a688463c7fca12c0fc23ab2751
Reviewed-on: https://go-review.googlesource.com/c/go/+/176439
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>