cmd/internal/obj/ppc64: remove unnecessary opcodes

This CL removes some opcode placeholders that do not correspond
to any existing instructions and hence create confusion. Some
instructions that are no longer valid like LDMX are also removed.
Any references to this instruction in ISA 3.0 are considered
as documentation errata.

Change-Id: Ib71a657099723bbe1db88873233ee573b5c42fe7
Reviewed-on: https://go-review.googlesource.com/c/go/+/429860
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Paul Murphy <murp@ibm.com>
Run-TryBot: Archana Ravindar <aravind5@in.ibm.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Archana Ravindar <aravind5@in.ibm.com>

all: fix some typos

Change-Id: I8b28aebbb9494b2c877139a4584a5a42253e3bea
GitHub-Last-Rev: e3703fd3a50b811785df75751472aa3ab098b3d1
GitHub-Pull-Request: golang/go#55902
Reviewed-on: https://go-review.googlesource.com/c/go/+/435617
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

cmd/compile: remove some lines from PPC64.rules

In CL 429035 Keith suggested removing some
rules that were covered by generic rules. This
follows up on that comment.

Change-Id: I57b6c9ae0cd85f33a0eb2fef8356575d3d7820fb
Reviewed-on: https://go-review.googlesource.com/c/go/+/430417
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>

cmd/go: support new hybrid coverage instrumentation

If GOEXPERIMENT=coverageredesign is in effect, introduce a new
top-level '-cover' option to "go build" to turn on new-style hybrid
code coverage instrumentation. Similarly, use the new instrumentation
for "go test -cover".

The main effects of "-cover" under the hood are to instrument files at
the package level using cmd/cover and to pass additional options to
the compiler when building instrumented packages.

The previous workflow for "go tool -cover mypkg" would expand to a
series of "go tool cover" commands (one per file) followed by a single
package compilation command to build the rewritten sources.

With the new workflow, the Go command will pass all of the Go files in
a package to the cover tool as a chunk (along with a config file
containing other parameters), then the cover tool will write
instrumented versions of the sources along with another "output"
config with info on coverage variable names for the the compiler. The
Go command will then kick off the compiler on the modified source
files, also passing in the config file generated by cmd/cover.

Updates #51430.

Change-Id: Id65621ff6a8c70a30168c1412c2d6f805ff3b9e7
Reviewed-on: https://go-review.googlesource.com/c/go/+/355452
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Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>

cmd/go: refactor package references in Builder.build

Refactor references to "a.Package" in Builder.build to be consistent,
e.g. all via the "p" helper variable. No change in functionality, this
is just intended to make the code more readable/consistent (since
prior to this point we had a random mix of "p" and "a.Package").

Change-Id: Ifea5ff9b314c39a0cf6e688511907d08cc56c603
Reviewed-on: https://go-review.googlesource.com/c/go/+/424819
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>

cmd/go: add hook to check for GOEXPERIMENT in script tests

Add a new hook to allow script tests to check whether a specific
GOEXPERIMENT is enabled.

Updates #51430.

Change-Id: Icdf39f845ff2c8b10c634d49e9c27bc90e7984f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/402174
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

cmd/cover: add hybrid instrumentation mode

Add a new mode of coverage instrumentation that works as a hybrid
between purely tool-based and purely compiler-based. The cmd/cover
tool still does source-to-source rewriting, but it also generates
information to be used by the compiler to do things like marking
meta-data vars as read-only.

In hybrid mode, the cmd/cover tool is invoked not on a single source
file but on all the files in a package, and is passed a config file
containing the import path of the package in question, along with
other parameters needed for the run. It writes a series of modified
files and an output config file to be passed to the compiler when
compiling the modified files.

Not completely useful by itself, still needs a corresponding set of
changes in the Go command and in the compiler.

Updates #51430.

Change-Id: I0fcbd93a9a8fc25064187b159152486a2549ea54
Reviewed-on: https://go-review.googlesource.com/c/go/+/395896
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>

runtime/coverage: runtime routines to emit coverage data

This patch fleshes out the runtime support for emitting coverage data
at the end of a run of an instrumented binary. Data is emitted in the
form of a pair of files, a meta-out-file and counter-data-outfile,
each written to the dir GOCOVERDIR. The meta-out-file is emitted only
if required; no need to emit again if an existing meta-data file with
the same hash and length is present.

Updates #51430.

Change-Id: I59d20a4b8c05910c933ee29527972f8e401b1685
Reviewed-on: https://go-review.googlesource.com/c/go/+/355451
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Than McIntosh <thanm@google.com>

cmd/covdata: add tools to read/manipulate coverage data files

Add a set of helper packages for reading collections of related
meta-data and counter-data files ("pods") produced by runs of
coverage-instrumented binaries, and a new tool program (cmd/covdata)
for dumping and/or manipulating coverage data files.

Currently "go tool covdata" subcommands include 'merge', 'intersect',
'percent', 'pkglist', 'subtract', 'debugdump', and 'textfmt'
(conversion to the legacy "go tool cover" format).

Updates #51430.

Change-Id: I44167c578f574b4636ab8726e726388531fd3258
Reviewed-on: https://go-review.googlesource.com/c/go/+/357609
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

go/types, types2: use "invalid operation: x rel y (cause)" for comparison error messages

Matches compiler behavior and is consistent with what we do with other
binary operations.

While at it, also use parentheses rather than a colon for a couple of
errors caused by not having a core type.

For #55326.

Change-Id: I0a5cec1a31ffda98d363e5528791965a1ccb5842
Reviewed-on: https://go-review.googlesource.com/c/go/+/435618
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
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Auto-Submit: Robert Griesemer <gri@google.com>
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time: add comment explaining >>33 in Now

Change-Id: I022b617cd345b412bee0b50a862676a1dca94e01
Reviewed-on: https://go-review.googlesource.com/c/go/+/418376
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

cmd/nm, runtime/cgo: add cgo support for freebsd/riscv64

Updates #53466

Change-Id: I08ea279c905e265a579b6b3e23aee012165beaee
Reviewed-on: https://go-review.googlesource.com/c/go/+/431658
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
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Run-TryBot: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Dmitri Goutnik <dgoutnik@gmail.com>

cmd/dist: enable cgo tests on freebsd/riscv64

Updates #53466

Change-Id: I17a41adb93c22fa84a7bdcec9d8c65001c5a8ba9
Reviewed-on: https://go-review.googlesource.com/c/go/+/431657
Reviewed-by: Dmitri Goutnik <dgoutnik@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Meng Zhuo <mzh@golangcn.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
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crypto: use bytes.Clone

Change-Id: I92e110023739c6f8f7815c7e47ad7639c4e8812d
Reviewed-on: https://go-review.googlesource.com/c/go/+/435279
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
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Run-TryBot: xie cui <523516579@qq.com>

net/textproto: use bytes.Clone

Change-Id: Ic73d667a98df3f2d1705a67e7e8625c6ba65cc0a
Reviewed-on: https://go-review.googlesource.com/c/go/+/435284
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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internal: use bytes.Clone

Change-Id: Ia96ddd520a7bd2fd53bff55315c6fac04ae96a2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/435282
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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encoding/xml: use bytes.Clone

Change-Id: I3218b1e3f8869f579facddb29471df13c835dc66
Reviewed-on: https://go-review.googlesource.com/c/go/+/435281
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runtime: add support for freebsd/riscv64

Updates #53466

Change-Id: I42ca5f1d0f20b5ecfcfba70d298566b6c851fefc
Reviewed-on: https://go-review.googlesource.com/c/go/+/431656
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Meng Zhuo <mzh@golangcn.org>
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database: use bytes.Clone

Change-Id: I66aad199884cffd51946f53f01580a3a353f5c97
Reviewed-on: https://go-review.googlesource.com/c/go/+/435280
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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Run-TryBot: Meng Zhuo <mzh@golangcn.org>

crypto/rsa,crypto/internal/boring: fix PSS salt handling

Fix the coversion between our sentinel salt length variables and the
BoringSSL versions in SignRSAPSS. We previously set -1 (hash length
equals salt length) when 0 was passed when we should've been setting
-2. This now matches the conversion that happens in VerifyRSAPSS. Also
adds a note documenting why we do this.

Additionally in non-Boring mode, properly handle passing of salt lengths
with a negative value which aren't one of the magic constants, returning
an error instead of panicking.

See https://commondatastorage.googleapis.com/chromium-boringssl-docs/rsa.h.html#RSA_sign_pss_mgf1
for the BoringSSL docs.

Fixes #54803

Change-Id: Id1bd14dcf0ef4733867367257830ed43e25ef882
Reviewed-on: https://go-review.googlesource.com/c/go/+/426659
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Reviewed-by: Damien Neil <dneil@google.com>
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go/types, types2: use 2nd operand position for comparison type mismatch errors

When a comparison is invalid due to mismatched types, we only know
when we see the 2nd operand; so use that operand's position for the
error message. This matches compiler behavior.

For #55326.

Change-Id: I79450756bbdd2b4bb90ed4e960a451be0197b186
Reviewed-on: https://go-review.googlesource.com/c/go/+/435555
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debug/elf: return error on reading from SHT_NOBITS sections

An SHT_NOBITS section contains no bytes and occupies no space in the
file. This change makes it return an error on reading from this section
so that it will force the caller to check for an SHT_NNOBITS section.

We have considered another option to return "nil, nil" for the Data
method. It's abandoned because it might lead a program to simply do
the wrong thing, thinking that the section is empty.

Please note that it breaks programs which expect a byte slice with the
length described by the sh_size field. There are two reasons to
introduce this breaking change: 1. SHT_NOBITS means no data and it's
unnecessary to allocate memory for it; 2. it could result in an OOM if
the file is corrupted and has a huge sh_size.

Fixes #54967.

Change-Id: I0c3ed4e097214fe88413d726a89122105ad45d4f
GitHub-Last-Rev: 994c12d9da8c7029ce1d26eb1eb4d333ef3b1f97
GitHub-Pull-Request: golang/go#54994
Reviewed-on: https://go-review.googlesource.com/c/go/+/429601
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crypto/x509: use unsafe.Slice

Change-Id: I40fdfbd5cfb9f5ccb80d55bca28ff9ba1ec490f3
Reviewed-on: https://go-review.googlesource.com/c/go/+/435285
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
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cmd/compile: use "method T.m already declared" for method redeclaration errors

Compromise between old compiler error "T.m redeclared in this block"
(where the "in this block" is not particularly helpful) and the old
type-checker error "method m already declared for type T ...".
In the case where we have position information for the original
declaration, the error message is "method T.m already declared at
<position>". The new message is both shorter and more precise.

For #55326.

Change-Id: Id4a7f326fe631b11db9e8030eccb417c72d6c7db
Reviewed-on: https://go-review.googlesource.com/c/go/+/435016
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go/types, types2: use "unknown field f in struct literal of type S" in error messages

This is a compromise of the error reported by the compiler (quotes
around field name removed) and the error reported by the type checkers
(added mention of struct type).

For #55326.

Change-Id: Iac4fb5c717f17c6713e90d327d39e68d3be40074
Reviewed-on: https://go-review.googlesource.com/c/go/+/434815
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go/types, types2: use "multiple-value" instead "n-valued" in error messages

This matches current compiler behavior.

For #55326.

Change-Id: I9ebe2914323072b5454fb9af2d15c9dd2d711bad
Reviewed-on: https://go-review.googlesource.com/c/go/+/434735
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go/types, types2: uniformly use "cannot convert X to type T"

This matches current compiler behavior.

For #55326.

Change-Id: I660bd15f13a8d9eb00fafa937f8261e664b0e065
Reviewed-on: https://go-review.googlesource.com/c/go/+/433276
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go/types, types2: use "and not used" instead of "but not used" in error messages

This matches longstanding compiler behavior.

Also, for unused packages, report:

`"pkg" imported and not used`
`"pkg" imported as X and not used`

This matches the other `X declared and not used` errors.

For #55326.

Change-Id: Ie71cf662fb5f4648449c64fc51bede298a1bdcbf
Reviewed-on: https://go-review.googlesource.com/c/go/+/432557
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cmd/compile: rework PPC64 Mul64uhilo lowering rules

Remove OpPPC64LoweredMuluhilo as this operation can be done
more efficiently with MULHDU and MULLD directly. This has the
benefit of not needing to use tuple select operations, and giving
the scheduler more freedom to place these operations.

The primary reason to avoid using tuples here is to to avoid
suboptimal scheduling when carry ops (e.x ADDC/ADDE) are used in
the same block as 64->128b multiples. CL 432275 modifies the
scheduling priorities which may cause non-flag/non-carry generating
tuple ops to interfere with carry opcodes. Thus resulting in excess
saving and restoring of the XER register.

This allows CL 432275 to adjust the scheduling priorities without
having to workaround odd tuple scheduling behavior.

Change-Id: Id04ef009ec4b86416e5436f2b44ae1474e73720e
Reviewed-on: https://go-review.googlesource.com/c/go/+/434855
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
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Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

cmd/compile: make a type-specialized copy of encoding/binary.ReadUvarint

This is to get better escape analysis for a frequently-allocated object.

Change-Id: I1942a4e1c3cd1f0fa870bc8433a0165c18ce9c75
Reviewed-on: https://go-review.googlesource.com/c/go/+/435336
Reviewed-by: Keith Randall <khr@golang.org>
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Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

cmd/compile: introduce "temporary" readers for more storage reuse

Change-Id: Id05d6099624284a9c1583b066d1a703e806b1e22
Reviewed-on: https://go-review.googlesource.com/c/go/+/433037
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@google.com>

cmd/compile: use stricter rule for possible partial overlap

Partial overlaps can only happen for strict sub-pieces of larger arrays.
That's a much stronger condition than the current optimization rules.

Update #54467

Change-Id: I11e539b71099e50175f37ee78fddf69283f83ee5
Reviewed-on: https://go-review.googlesource.com/c/go/+/433056
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Reviewed-by: David Chase <drchase@google.com>
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Reviewed-by: Matthew Dempsky <mdempsky@google.com>

go/scanner: emit implicit semicolon tokens in correct order

Prior to this change, the scanner, in ScanComments mode, would emit
the implicit SEMICOLON token generated by a newline ahead of any
immediately preceding comment "tokens". For example:

 foo /*a*/ /*b*/ /*c*/ \n   =>  [IDENT SEMICOLON COMMENT COMMENT COMMENT]

Now, tokens and comments are emitted by the scanner in lexical order
of their start position. SEMICOLON tokens corresponding to newlines
always have the position of the newline (even in the special case
in which the newline is in the middle of a general comment /*\n*/).

The scanner no longer needs to look ahead, possibly across multiple
comments, for a newline, when it encounters a comment.
The scanner semicolon tests have been rewritten to be less magical.

The parser must now expect line comments before an implicit semicolon.
Line comments for an explicit semicolon still appear after.
The new assertions in the parser TestLeadAndLineComments are
not changes to behavior.

Fixes golang/go#54941

Change-Id: Iffe97fd10e9e0b52882da8659307698ccb31c093
Reviewed-on: https://go-review.googlesource.com/c/go/+/429635
Auto-Submit: Alan Donovan <adonovan@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Alan Donovan <adonovan@google.com>

bufio: use bytes.Clone

Change-Id: Ic21d979da8be1a6047b9bcd65b5ee71ca2ef7548
Reviewed-on: https://go-review.googlesource.com/c/go/+/435278
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>

cmd/link: fix coverage counter issue on AIX

Update the linker's XCOFF writer to handle coverage counter sections
properly; they need to be treated as bss, not data. Fixes a problem
with the aix-ppc64 builder introduced in CL 401235), e.g.
"runtime.covctrs: A symbol with type XTY_SD must be in a .text or
.data section".

Updates #51430.

Change-Id: I3fc385a37e2549c46cc7cc3b4718af989a36752a
Reviewed-on: https://go-review.googlesource.com/c/go/+/435335
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: David Chase <drchase@google.com>

cmd/internal/pkgpath: use MustHaveExec in TestToSymbolFunc

ToSymbolFunc executes a command using exec.Command.

Change-Id: Ic6c274bdc23050d021ec98ba67748338ac34f12c
Reviewed-on: https://go-review.googlesource.com/c/go/+/435236
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Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>

cmd/api: skip tests on platforms that cannot exec

These tests execute commands using exec.Command.

Change-Id: I2708d6d24762fe2b2a902b1b221cc67392bf5c41
Reviewed-on: https://go-review.googlesource.com/c/go/+/435235
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>

cmd/link: refactor usage of SymLocalentry helper functions

PPC64 ELFv2 uses the st_other field of a symbol to specify an offset
from the global entry point to its local entry point. Similarly, some
values (i.e 1) may also require additional linker support which is
missing today.

For now, generate an error if we encounter unsupported local entry
values on PPC64, and update the Localentry values to use bytes, not
32b instruction words.

Similarly, ELFv2 1.5 also updates the wording of values 2-6. They
now map to a specific number of bytes.

Change-Id: Id1b71c3b0fea982bdcfb7eac91d9f93e04ae43f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/431876
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Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

misc/wasm: update deprecated substr usage

String.prototype.substr is deprecated and usage is no longer
recommended so using String.prototype.substring instead.

Change-Id: I9eb49a8c065890df73301e3a04af59f550bc3ae1
Reviewed-on: https://go-review.googlesource.com/c/go/+/406094
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Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

runtime: using bytes.CutPrefix

Change-Id: I3f2dae17496b5b4efbdc022802f941a616abd87a
Reviewed-on: https://go-review.googlesource.com/c/go/+/435276
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Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

cmd/compile: abstract type type+value obtained from types2

In preparation for encoding it in a more efficient way.

Change-Id: I299dd2befc3d07107a1b7b49225bbb9f2e48a343
Reviewed-on: https://go-review.googlesource.com/c/go/+/432896
Reviewed-by: Cherry Mui <cherryyz@google.com>
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Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

bytes,strings: optimize Repeat

When generating long strings or slices with Repeat we
currently reuse intermediate states as a way to quickly
build exponentially longer results.

This works well as long as the intermediate states fit into
the processor D-cache. If they don't we start thrashing the
D-cache by reading in the whole intermediate state over and
over on each iteration.

Instead, once we reach a large enough intermediate state (that
allows the memcpy operation to perform at peak) we cap the
size of chunk of the state that is used as source for subsequent
appends. This ensures that this smaller source chunk is always
present in the D-cache, and the append operation does not need
to read the state contents from memory.

Currently the cap is set to 8KB, a number derived via
experimentation to yield the highest performance across a
a large range of result sizes. Slightly higher caps also
produced similar results: 8KB was chosen as the smallest one
in this performance plateau with the intention to minimize
D-cache pollution.

For result sizes larger than the fastest cache levels we get
significantly higher performance compared to the current
implementation:
strings:
name                            old speed      new speed      delta
RepeatLarge/256/1-16            1.73GB/s ± 1%  1.73GB/s ± 0%      ~     (p=0.556 n=5+4)
RepeatLarge/256/16-16           2.02GB/s ± 0%  1.95GB/s ± 8%      ~     (p=0.222 n=5+5)
RepeatLarge/512/1-16            2.30GB/s ±13%  2.47GB/s ± 1%      ~     (p=0.548 n=5+5)
RepeatLarge/512/16-16           2.38GB/s ±16%  2.77GB/s ± 1%   +16.27%  (p=0.032 n=5+5)
RepeatLarge/1024/1-16           3.17GB/s ± 1%  3.18GB/s ± 0%      ~     (p=0.730 n=4+5)
RepeatLarge/1024/16-16          3.39GB/s ± 2%  3.38GB/s ± 1%      ~     (p=0.548 n=5+5)
RepeatLarge/2048/1-16           3.32GB/s ± 2%  3.32GB/s ± 2%      ~     (p=1.000 n=5+5)
RepeatLarge/2048/16-16          3.41GB/s ± 4%  3.46GB/s ± 2%      ~     (p=0.310 n=5+5)
RepeatLarge/4096/1-16           3.60GB/s ± 4%  3.67GB/s ± 3%      ~     (p=0.690 n=5+5)
RepeatLarge/4096/16-16          3.74GB/s ± 3%  3.71GB/s ± 5%      ~     (p=0.690 n=5+5)
RepeatLarge/8192/1-16           3.94GB/s ± 4%  4.01GB/s ± 1%      ~     (p=0.222 n=5+5)
RepeatLarge/8192/16-16          3.94GB/s ± 6%  4.05GB/s ± 1%      ~     (p=0.222 n=5+5)
RepeatLarge/8192/4097-16        4.25GB/s ± 6%  4.32GB/s ± 3%      ~     (p=0.690 n=5+5)
RepeatLarge/16384/1-16          4.96GB/s ± 1%  5.02GB/s ± 2%      ~     (p=0.421 n=5+5)
RepeatLarge/16384/16-16         4.99GB/s ± 2%  5.07GB/s ± 1%      ~     (p=0.421 n=5+5)
RepeatLarge/16384/4097-16       5.15GB/s ± 3%  5.17GB/s ± 1%      ~     (p=1.000 n=5+5)
RepeatLarge/32768/1-16          5.44GB/s ± 2%  5.42GB/s ± 1%      ~     (p=0.841 n=5+5)
RepeatLarge/32768/16-16         5.46GB/s ± 4%  5.44GB/s ± 1%      ~     (p=0.905 n=5+4)
RepeatLarge/32768/4097-16       4.84GB/s ± 2%  4.59GB/s ±12%    -5.05%  (p=0.032 n=5+5)
RepeatLarge/65536/1-16          5.85GB/s ± 0%  5.84GB/s ± 1%      ~     (p=0.690 n=5+5)
RepeatLarge/65536/16-16         5.81GB/s ± 2%  5.84GB/s ± 2%      ~     (p=0.421 n=5+5)
RepeatLarge/65536/4097-16       5.38GB/s ± 6%  5.45GB/s ± 1%      ~     (p=1.000 n=5+5)
RepeatLarge/131072/1-16         6.20GB/s ± 1%  6.31GB/s ± 1%    +1.80%  (p=0.008 n=5+5)
RepeatLarge/131072/16-16        6.12GB/s ± 3%  6.25GB/s ± 3%      ~     (p=0.095 n=5+5)
RepeatLarge/131072/4097-16      5.95GB/s ± 1%  5.85GB/s ±10%      ~     (p=1.000 n=5+5)
RepeatLarge/262144/1-16         6.33GB/s ± 1%  6.56GB/s ± 0%    +3.62%  (p=0.016 n=5+4)
RepeatLarge/262144/16-16        6.42GB/s ± 0%  6.65GB/s ± 1%    +3.58%  (p=0.016 n=4+5)
RepeatLarge/262144/4097-16      6.31GB/s ± 1%  6.44GB/s ± 1%    +1.94%  (p=0.008 n=5+5)
RepeatLarge/524288/1-16         6.23GB/s ± 1%  6.92GB/s ± 3%   +11.02%  (p=0.008 n=5+5)
RepeatLarge/524288/16-16        6.24GB/s ± 1%  6.97GB/s ± 2%   +11.77%  (p=0.016 n=4+5)
RepeatLarge/524288/4097-16      6.14GB/s ± 2%  6.73GB/s ± 3%    +9.50%  (p=0.008 n=5+5)
RepeatLarge/1048576/1-16        5.23GB/s ± 1%  6.53GB/s ± 6%   +24.85%  (p=0.008 n=5+5)
RepeatLarge/1048576/16-16       5.21GB/s ± 1%  6.56GB/s ± 4%   +25.93%  (p=0.008 n=5+5)
RepeatLarge/1048576/4097-16     5.22GB/s ± 1%  6.26GB/s ± 2%   +20.09%  (p=0.008 n=5+5)
RepeatLarge/2097152/1-16        3.95GB/s ± 1%  5.96GB/s ± 1%   +51.01%  (p=0.008 n=5+5)
RepeatLarge/2097152/16-16       3.94GB/s ± 1%  5.98GB/s ± 2%   +51.99%  (p=0.008 n=5+5)
RepeatLarge/2097152/4097-16     4.94GB/s ± 1%  5.71GB/s ± 2%   +15.63%  (p=0.008 n=5+5)
RepeatLarge/4194304/1-16        3.10GB/s ± 1%  5.89GB/s ± 1%   +89.90%  (p=0.008 n=5+5)
RepeatLarge/4194304/16-16       3.09GB/s ± 1%  5.86GB/s ± 1%   +89.89%  (p=0.008 n=5+5)
RepeatLarge/4194304/4097-16     3.13GB/s ± 1%  5.89GB/s ± 1%   +88.36%  (p=0.008 n=5+5)
RepeatLarge/8388608/1-16        3.06GB/s ± 1%  6.31GB/s ±16%  +105.84%  (p=0.008 n=5+5)
RepeatLarge/8388608/16-16       3.08GB/s ± 1%  6.62GB/s ± 1%  +114.66%  (p=0.008 n=5+5)
RepeatLarge/8388608/4097-16     3.13GB/s ± 2%  6.87GB/s ± 1%  +119.62%  (p=0.008 n=5+5)
RepeatLarge/16777216/1-16       3.21GB/s ± 3%  5.88GB/s ± 1%   +83.27%  (p=0.008 n=5+5)
RepeatLarge/16777216/16-16      3.23GB/s ± 2%  5.84GB/s ± 2%   +80.49%  (p=0.008 n=5+5)
RepeatLarge/16777216/4097-16    3.30GB/s ± 6%  5.88GB/s ± 2%   +78.18%  (p=0.008 n=5+5)
RepeatLarge/33554432/1-16       3.71GB/s ± 3%  5.91GB/s ± 2%   +59.17%  (p=0.008 n=5+5)
RepeatLarge/33554432/16-16      3.67GB/s ± 3%  5.91GB/s ± 2%   +61.13%  (p=0.008 n=5+5)
RepeatLarge/33554432/4097-16    3.71GB/s ± 1%  5.77GB/s ± 6%   +55.51%  (p=0.008 n=5+5)
RepeatLarge/67108864/1-16       4.61GB/s ±11%  6.00GB/s ± 5%   +30.15%  (p=0.008 n=5+5)
RepeatLarge/67108864/16-16      4.62GB/s ± 7%  6.11GB/s ± 2%   +32.35%  (p=0.008 n=5+5)
RepeatLarge/67108864/4097-16    4.71GB/s ± 2%  6.24GB/s ± 2%   +32.60%  (p=0.008 n=5+5)
RepeatLarge/134217728/1-16      4.53GB/s ± 8%  6.28GB/s ±11%   +38.57%  (p=0.008 n=5+5)
RepeatLarge/134217728/16-16     4.78GB/s ± 3%  6.36GB/s ± 3%   +33.16%  (p=0.008 n=5+5)
RepeatLarge/134217728/4097-16   4.73GB/s ± 6%  6.46GB/s ± 3%   +36.63%  (p=0.008 n=5+5)
RepeatLarge/268435456/1-16      4.09GB/s ±25%  6.37GB/s ±19%   +56.00%  (p=0.008 n=5+5)
RepeatLarge/268435456/16-16     4.50GB/s ± 4%  6.86GB/s ± 0%   +52.49%  (p=0.016 n=5+4)
RepeatLarge/268435456/4097-16   4.73GB/s ± 5%  6.90GB/s ± 0%   +45.94%  (p=0.008 n=5+5)
RepeatLarge/536870912/1-16      4.38GB/s ±36%  6.52GB/s ± 8%   +48.68%  (p=0.008 n=5+5)
RepeatLarge/536870912/16-16     4.69GB/s ±12%  6.90GB/s ± 1%   +46.97%  (p=0.008 n=5+5)
RepeatLarge/536870912/4097-16   4.87GB/s ± 8%  6.98GB/s ± 0%   +43.36%  (p=0.008 n=5+5)
RepeatLarge/1073741824/1-16     3.87GB/s ±28%  6.96GB/s ± 1%   +79.94%  (p=0.016 n=5+4)
RepeatLarge/1073741824/16-16    4.79GB/s ± 9%  6.93GB/s ± 0%   +44.79%  (p=0.008 n=5+5)
RepeatLarge/1073741824/4097-16  4.65GB/s ± 8%  7.02GB/s ± 1%   +51.02%  (p=0.008 n=5+5)

bytes:
name                            old speed      new speed      delta
RepeatLarge/256/1-16            1.93GB/s ± 1%  1.84GB/s ± 1%    -4.81%  (p=0.000 n=10+10)
RepeatLarge/256/16-16           2.25GB/s ± 2%  2.15GB/s ± 1%    -4.45%  (p=0.000 n=9+8)
RepeatLarge/512/1-16            2.71GB/s ± 1%  2.62GB/s ± 1%    -3.27%  (p=0.000 n=10+9)
RepeatLarge/512/16-16           2.96GB/s ± 4%  2.91GB/s ± 1%      ~     (p=0.243 n=9+10)
RepeatLarge/1024/1-16           3.35GB/s ± 1%  3.27GB/s ± 1%    -2.61%  (p=0.000 n=9+10)
RepeatLarge/1024/16-16          3.56GB/s ± 2%  3.52GB/s ± 1%    -1.10%  (p=0.010 n=10+9)
RepeatLarge/2048/1-16           3.52GB/s ± 1%  3.45GB/s ± 1%    -1.92%  (p=0.000 n=10+10)
RepeatLarge/2048/16-16          3.61GB/s ± 1%  3.58GB/s ± 0%    -0.82%  (p=0.008 n=9+8)
RepeatLarge/4096/1-16           3.85GB/s ± 2%  3.80GB/s ± 2%      ~     (p=0.165 n=10+10)
RepeatLarge/4096/16-16          3.88GB/s ± 3%  3.84GB/s ± 4%      ~     (p=0.393 n=10+10)
RepeatLarge/8192/1-16           4.12GB/s ± 2%  4.04GB/s ± 1%    -1.96%  (p=0.000 n=10+10)
RepeatLarge/8192/16-16          4.11GB/s ± 2%  4.09GB/s ± 1%      ~     (p=0.278 n=9+10)
RepeatLarge/8192/4097-16        4.38GB/s ± 1%  4.39GB/s ± 4%      ~     (p=0.720 n=9+10)
RepeatLarge/16384/1-16          5.06GB/s ± 2%  4.95GB/s ± 3%    -2.29%  (p=0.001 n=10+9)
RepeatLarge/16384/16-16         5.11GB/s ± 3%  5.06GB/s ± 3%      ~     (p=0.315 n=10+9)
RepeatLarge/16384/4097-16       5.22GB/s ± 3%  5.26GB/s ± 3%      ~     (p=0.211 n=9+10)
RepeatLarge/32768/1-16          5.54GB/s ± 2%  5.50GB/s ± 3%      ~     (p=0.353 n=10+10)
RepeatLarge/32768/16-16         5.55GB/s ± 1%  5.60GB/s ± 1%    +0.91%  (p=0.035 n=10+9)
RepeatLarge/32768/4097-16       4.88GB/s ± 2%  4.85GB/s ± 2%      ~     (p=0.447 n=10+9)
RepeatLarge/65536/1-16          5.86GB/s ± 1%  5.93GB/s ± 2%    +1.18%  (p=0.043 n=8+10)
RepeatLarge/65536/16-16         5.83GB/s ± 2%  5.98GB/s ± 1%    +2.67%  (p=0.000 n=10+10)
RepeatLarge/65536/4097-16       5.57GB/s ± 0%  5.56GB/s ± 3%      ~     (p=0.696 n=8+10)
RepeatLarge/131072/1-16         6.23GB/s ± 1%  6.38GB/s ± 2%    +2.51%  (p=0.000 n=9+10)
RepeatLarge/131072/16-16        6.21GB/s ± 2%  6.37GB/s ± 1%    +2.72%  (p=0.000 n=9+10)
RepeatLarge/131072/4097-16      6.04GB/s ± 1%  6.09GB/s ± 3%      ~     (p=0.356 n=9+10)
RepeatLarge/262144/1-16         6.47GB/s ± 1%  6.63GB/s ± 2%    +2.57%  (p=0.003 n=10+10)
RepeatLarge/262144/16-16        6.45GB/s ± 2%  6.69GB/s ± 2%    +3.65%  (p=0.000 n=10+10)
RepeatLarge/262144/4097-16      6.35GB/s ± 1%  6.51GB/s ± 2%    +2.48%  (p=0.000 n=9+10)
RepeatLarge/524288/1-16         6.21GB/s ± 2%  6.95GB/s ± 1%   +11.95%  (p=0.000 n=10+10)
RepeatLarge/524288/16-16        6.24GB/s ± 2%  6.93GB/s ± 2%   +11.11%  (p=0.000 n=10+10)
RepeatLarge/524288/4097-16      6.18GB/s ± 2%  6.82GB/s ± 1%   +10.39%  (p=0.000 n=9+10)
RepeatLarge/1048576/1-16        5.34GB/s ± 2%  6.41GB/s ± 2%   +20.05%  (p=0.000 n=10+10)
RepeatLarge/1048576/16-16       5.33GB/s ± 1%  6.45GB/s ± 2%   +20.84%  (p=0.000 n=10+9)
RepeatLarge/1048576/4097-16     5.28GB/s ± 1%  6.17GB/s ± 2%   +16.75%  (p=0.000 n=10+10)
RepeatLarge/2097152/1-16        4.04GB/s ± 1%  6.21GB/s ± 1%   +53.89%  (p=0.000 n=9+8)
RepeatLarge/2097152/16-16       4.02GB/s ± 1%  6.20GB/s ± 2%   +54.37%  (p=0.000 n=10+9)
RepeatLarge/2097152/4097-16     4.94GB/s ± 1%  6.04GB/s ± 1%   +22.36%  (p=0.000 n=10+10)
RepeatLarge/4194304/1-16        3.10GB/s ± 1%  5.74GB/s ± 0%   +85.04%  (p=0.000 n=10+9)
RepeatLarge/4194304/16-16       3.10GB/s ± 2%  5.72GB/s ± 1%   +84.26%  (p=0.000 n=9+10)
RepeatLarge/4194304/4097-16     3.03GB/s ± 4%  5.61GB/s ± 1%   +85.06%  (p=0.000 n=10+9)
RepeatLarge/8388608/1-16        3.08GB/s ± 2%  6.25GB/s ± 1%  +103.09%  (p=0.000 n=9+9)
RepeatLarge/8388608/16-16       3.07GB/s ± 2%  6.26GB/s ± 3%  +104.07%  (p=0.000 n=10+9)
RepeatLarge/8388608/4097-16     3.08GB/s ± 2%  6.23GB/s ± 2%  +102.09%  (p=0.000 n=9+10)
RepeatLarge/16777216/1-16       3.25GB/s ± 2%  5.78GB/s ± 3%   +78.03%  (p=0.000 n=9+9)
RepeatLarge/16777216/16-16      3.25GB/s ± 1%  5.75GB/s ± 1%   +77.21%  (p=0.000 n=9+10)
RepeatLarge/16777216/4097-16    3.29GB/s ± 3%  5.72GB/s ± 2%   +73.74%  (p=0.000 n=10+10)
RepeatLarge/33554432/1-16       3.68GB/s ± 2%  5.90GB/s ± 1%   +60.20%  (p=0.000 n=10+10)
RepeatLarge/33554432/16-16      3.69GB/s ± 3%  5.88GB/s ± 1%   +59.54%  (p=0.000 n=10+9)
RepeatLarge/33554432/4097-16    3.74GB/s ± 1%  5.94GB/s ± 2%   +58.68%  (p=0.000 n=7+10)
RepeatLarge/67108864/1-16       4.62GB/s ±12%  6.11GB/s ± 3%   +32.23%  (p=0.000 n=10+9)
RepeatLarge/67108864/16-16      4.77GB/s ± 2%  6.09GB/s ± 2%   +27.88%  (p=0.000 n=9+9)
RepeatLarge/67108864/4097-16    4.78GB/s ± 1%  6.19GB/s ± 1%   +29.51%  (p=0.000 n=9+10)
RepeatLarge/134217728/1-16      4.60GB/s ±16%  6.52GB/s ± 9%   +41.67%  (p=0.000 n=10+10)
RepeatLarge/134217728/16-16     4.80GB/s ± 4%  6.81GB/s ± 2%   +41.82%  (p=0.000 n=10+9)
RepeatLarge/134217728/4097-16   4.79GB/s ± 4%  6.81GB/s ± 2%   +42.31%  (p=0.000 n=9+10)
RepeatLarge/268435456/1-16      4.43GB/s ±25%  6.27GB/s ±14%   +41.52%  (p=0.000 n=10+10)
RepeatLarge/268435456/16-16     4.75GB/s ± 4%  6.68GB/s ± 4%   +40.50%  (p=0.000 n=9+10)
RepeatLarge/268435456/4097-16   4.75GB/s ± 3%  6.58GB/s ± 4%   +38.68%  (p=0.000 n=9+10)
RepeatLarge/536870912/1-16      4.96GB/s ± 9%  6.39GB/s ±16%   +28.90%  (p=0.000 n=8+10)
RepeatLarge/536870912/16-16     4.66GB/s ± 6%  6.57GB/s ± 7%   +40.82%  (p=0.000 n=10+9)
RepeatLarge/536870912/4097-16   4.68GB/s ±11%  6.88GB/s ± 3%   +47.01%  (p=0.000 n=10+9)
RepeatLarge/1073741824/1-16     4.39GB/s ±23%  6.57GB/s ± 5%   +49.75%  (p=0.000 n=10+8)
RepeatLarge/1073741824/16-16    4.73GB/s ±13%  6.89GB/s ± 1%   +45.68%  (p=0.000 n=9+8)
RepeatLarge/1073741824/4097-16  4.97GB/s ±15%  6.73GB/s ± 9%   +35.45%  (p=0.000 n=10+10)

The results above come from a Intel i9-9980HK (256KB L2) with
TurboBoost disabled.

Change-Id: I79dd57da0429aee9020ffd7bc458a034b999b740
Reviewed-on: https://go-review.googlesource.com/c/go/+/419054
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

debug/elf: suport files with >= 65280 (0xff00) sections

The spec https://refspecs.linuxfoundation.org/elf/gabi4+/ch4.eheader.html
states:

1. e_shnum: If the number of sections is greater than or equal to
SHN_LORESERVE (0xff00), this member has the value zero and the actual
number of section header table entries is contained in the sh_size
field of the section header at index 0.

2. e_shstrndx: If the section name string table section index is
greater than or equal to SHN_LORESERVE (0xff00), this member has the
value SHN_XINDEX (0xffff) and the actual index of the section name
string table section is contained in the sh_link field of the section
header at index 0.

This CL makes these changes to support files with >= 0xff00 sections:

1. if shoff > 0 && shnum == 0, read sh_size from the initial section
header entry as shnum.
2. if shstrndx == SHN_XINDEX, read sh_link from the initial section
header entry as shstrndx.

It returns an error if the type of the initial section is not SHT_NULL.

A file with >= 0xff00 sections is too big to include in the repository,
so the test case constructs one on the fly, with some of the sections
zeroed out.

While here, remove the unnecessary use of reflect.DeepEqual in the test.

Fixes #55294.

Change-Id: I15ec43612c7cce6e8decfe4e81da3a5b16de47f7
GitHub-Last-Rev: 797c16480bc76524ff1a7c01ed09b759fcd7d45b
GitHub-Pull-Request: golang/go#55295
Reviewed-on: https://go-review.googlesource.com/c/go/+/432255
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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Reviewed-by: Ian Lance Taylor <iant@google.com>
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cmd: relocate search.MatchPattern to cmd/internal/pkgpattern

Relocate cmd/go's search.MatchPattern helper routine to a new package
in cmd/internal from its current location, as to allow it to be used
in other tools that accept package pattern command line flags. No
change in functionality along the way.

Updates #51430.

Change-Id: I726e974ccd66a055bb5a94497b36b8d68d47cad1
Reviewed-on: https://go-review.googlesource.com/c/go/+/432757
Reviewed-by: Bryan Mills <bcmills@google.com>

runtime/trace: add missing events for the locked g in extra M.

Extra Ms may lead to the "no consistent ordering of events possible" error when parsing trace file with cgo enabled, since:
1. The gs in the extra Ms may be in `_Gdead` status while starting trace by invoking `runtime.StartTrace`,
2. and these gs will trigger `traceEvGoSysExit` events in `runtime.exitsyscall` when invoking go functions from c,
3. then, the events of those gs are under non-consistent ordering, due to missing the previous events.

Add two events, `traceEvGoCreate` and `traceEvGoInSyscall`, in `runtime.StartTrace`, will make the trace parser happy.

Fixes #29707

Change-Id: I2fd9d1713cda22f0ddb36efe1ab351f88da10881
GitHub-Last-Rev: 7bbfddb81b70041250e3c59ce53bea44f7afd2c3
GitHub-Pull-Request: golang/go#54974
Reviewed-on: https://go-review.googlesource.com/c/go/+/429858
Run-TryBot: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: xie cui <523516579@qq.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Michael Pratt <mpratt@google.com>

cmd/go/internal: use strings.CutSuffix

Updates #42537

Change-Id: I2d4c5e911c8a2ddfe9a976896b05d3cd8be61f6b
GitHub-Last-Rev: a87597d8a7a84c4975fb5e13004feda9b6abce34
GitHub-Pull-Request: golang/go#55830
Reviewed-on: https://go-review.googlesource.com/c/go/+/433275
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Reviewed-by: Benny Siegert <bsiegert@gmail.com>
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reflect: clarify that Value.Comparable checks the value

For #46746

Change-Id: Ic7a31ddf7cd6bf6dd0db6b9eb3fee68fc180f72e
Reviewed-on: https://go-review.googlesource.com/c/go/+/435277
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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debug/dwarf: don't crash on invalid range/rnglist offset

No test case because the problem can only happen for invalid data. Let
the fuzzer find cases like this.

Fixes #53529

Change-Id: I318c87795e545fe5a006d16b4d361cd4bf5d502d
Reviewed-on: https://go-review.googlesource.com/c/go/+/434936
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Reviewed-by: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Than McIntosh <thanm@google.com>

net/http: fix the potential leak of textproto.Reader from pool

Fixes #55835

Change-Id: I6109bab2941b859e8cfef22f65a6a3a5f977a8d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/433835
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
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Run-TryBot: Andy Pan <panjf2000@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>

image/gif,image/jpeg,image/png: skip FuzzDecode in testing short mode

The image/gif.FuzzDecode takes an excessive amount of time to run on various
builders - skip these in testing short mode. Likewise for image/jpeg and
image/png.

Fixes #55839

Change-Id: I1049d06b9dcbbc7dbc4f53d3c49b64e2254eabbd
Reviewed-on: https://go-review.googlesource.com/c/go/+/435175
Reviewed-by: Roland Shoemaker <roland@golang.org>
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Reviewed-by: Bryan Mills <bcmills@google.com>

internal/goroot: using strings.CutPrefix replace strings.HasPrefix and strings.TrimPrefix

Change-Id: I63b2af955e2ada6d20e72c10797576d93bbc7e71
Reviewed-on: https://go-review.googlesource.com/c/go/+/435135
Reviewed-by: Ian Lance Taylor <iant@google.com>
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all: replace [0-9] with \d in regexps

1. replace [0-9] with \d in regexps
2. replace [a-zA-Z0-9_] with \w in regexps

Change-Id: I9e260538252a0c1071e76aeb1c5f885c6843a431
GitHub-Last-Rev: 286e1a4619c4bdda7f461afbd6d30b9f312c0486
GitHub-Pull-Request: golang/go#54874
Reviewed-on: https://go-review.googlesource.com/c/go/+/428435
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
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Run-TryBot: Ian Lance Taylor <iant@google.com>

runtime: add cgo guard for exit hooks test

Add an additional guard to ensure that we don't try to run the "-race"
variant of the exit hooks test when CGO is explicitly turned off via
CGO_ENABLED=0 (this fixes a failure on the no-cgo builder caused
by CL 354790).

Change-Id: I9dc7fbd71962e9a098916da69d9119a753f27116
Reviewed-on: https://go-review.googlesource.com/c/go/+/434935
Run-TryBot: Than McIntosh <thanm@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
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cmd/go/internal: use time.DateTime constant

Use the newly defined time.Datetime constant instead of a string literal.

Updates #52746

Change-Id: I2722415ecc67fd2adfdab2eaba3298774032bff3
GitHub-Last-Rev: 65d3aa9bc229cf6d07d6d0c1aaee4ada9056cd49
GitHub-Pull-Request: golang/go#55833
Reviewed-on: https://go-review.googlesource.com/c/go/+/433277
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
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cmd/compile: add coverage fixup mode

Adds a -coveragecfg=<configfile> command line option to the compiler
to help support a cooperative "tool and compiler" mode for coverage
instrumentation. In this mode the cmd/cover tool generates most of the
counter instrumentation via source-to-source rewriting, but the
compiler fixes up the result if passed the "-coveragecfg" option. The
fixups include:

  - reclassifying counter variables (special storage class)
  - marking meta-data variables are read-only
  - adding in an init call to do registation

Updates #51430.

Change-Id: Iead72b85209725ee044542374465f118a3ee72e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/395895
Reviewed-by: David Chase <drchase@google.com>
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cmd/compile,cmd/link: hooks for identifying coverage counters

Add a new "coverage counter" classification for variables to be used
for storing code coverage counter values (somewhat in the same way
that we identify fuzzer counters). Tagging such variables allows us to
aggregate them in the linker, and to treat updates specially.

Updates #51430.

Change-Id: Ib49fb05736ffece98bcc2f7a7c37e991b7f67bbb
Reviewed-on: https://go-review.googlesource.com/c/go/+/401235
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
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all: use strings.CutPrefix

Updates #42537

Change-Id: Ice23d7d36bbede27551cbc086119694f6a3b5e4a
GitHub-Last-Rev: 0d65208313ea318725159186fad045fc6400fb25
GitHub-Pull-Request: golang/go#55347
Reviewed-on: https://go-review.googlesource.com/c/go/+/432895
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
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go/types, types2: report "undefined: p.x" instead of "x not declared by package p"

This matches the compiler's long-standing behavior.

For #55326.

Change-Id: Icd946b031b1b6e65498fb52bceb4a53807732463
Reviewed-on: https://go-review.googlesource.com/c/go/+/432556
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
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go/types, types2: report "undefined: x" instead of "undeclared name: x"

This matches the compiler's long-standing behavior.

For #55326.

Change-Id: I90696a11f0b7d1f4be95a4b9a6f01844df2a2347
Reviewed-on: https://go-review.googlesource.com/c/go/+/432555
Run-TryBot: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
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sync: clarify Cond.Wait documentation

The previous wording was unclear and seemingly contradictory.

Change-Id: I0781dc4525948f4e8e5698271362a82387688f81
GitHub-Last-Rev: c1e032fa9451dd50a69cf572cd80dcdbe6591d2e
GitHub-Pull-Request: golang/go#53516
Reviewed-on: https://go-review.googlesource.com/c/go/+/413774
Reviewed-by: Ian Lance Taylor <iant@google.com>
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runtime: add an exit hook facility

Add a new API (not public/exported) for registering a function with
the runtime that should be called when program execution terminates,
to be used in the new code coverage re-implementation. The API looks
like

  func addExitHook(f func(), runOnNonZeroExit bool)

The first argument is the function to be run, second argument controls
whether the function is invoked even if there is a call to os.Exit
with a non-zero status. Exit hooks are run in reverse order of
registration, e.g. the first hook to be registered will be the last to
run. Exit hook functions are not allowed to panic or to make calls to
os.Exit.

Updates #51430.

Change-Id: I906f8c5184b7c1666f05a62cfc7833bf1a4300c4
Reviewed-on: https://go-review.googlesource.com/c/go/+/354790
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runtime: add hook to register coverage-instrumented packages

Add support to the runtime for registering coverage-instrumented
packages, using a new hook that can be called from the init function
of an instrumented package. The hook records the meta-data symbol for
the package (chaining it onto a list), and returns a package ID to be
used to identify functions in the package. This new hook is not yet
called; that will be added in a subsequent patch. The list of
registered meta-data objects will be used (again in a future patch) as
part of coverage data file writing.

Special handling is required for packages such as "runtime" or
"internal/cpu", where functions in the package execute before the
package "init" func runs. For these packages hard-code the package ID,
then record the position of the package in the overall list so that we
can fix things up later on.

Updates #51430.

Change-Id: I6ca3ddf535197442a2603c6d7a0a9798b8496f40
Reviewed-on: https://go-review.googlesource.com/c/go/+/401234
Reviewed-by: Michael Knyszek <mknyszek@google.com>
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internal/coverage: add apis for reading/writing counter data

Add utilities for reading and writing of counter data files as part of
the new code coverage implementation.

Trivia note: currently the contents of counter data files are emitted
in little-endian form, which for the counters is somewhat painful in
that we need to visit each counter value and properly encode it. It
might be better to instead emit counters in native endianity and then
teach the tools to decode properly in the case of an endianity
mismatch.

Updates #51430.

Change-Id: I124fdcb40fc339a48b64b35264bf24c3be50ddd4
Reviewed-on: https://go-review.googlesource.com/c/go/+/359403
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reflect: create funcTypes using StructOf

follow the TODO to use StructOf, this cl can save the used memory.
for example, old code alloc [128]*rtype for func with 65 arguments(in+out),
this cl change to alloc [65]*rtype to save memory.

Change-Id: I1494bb6b3524d0d46869c3f24a628fec88119d8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/425314
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

go/types, types2: use "invalid recursive type" instead of "illegal cycle" in error messages

This matches long-standing compiler behavior.

For #55326.

Change-Id: Ic5aa0dfb08d035f2c33532cc463c73a55cc020a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/433055
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>

go/types, types2: provide error codes where they were missing

We need a better approach eventually, but this is ok for now.
In go/types, always use _UnsupportedFeature for unavailable
version-specific features.

Change-Id: I15b47e34eda167db3133bd481aa2f55cf3662c31
Reviewed-on: https://go-review.googlesource.com/c/go/+/433195
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>

internal/coverage: add coverage meta-data decoder

Add a coverage meta-data decoder, which provides APIs for reading
encoded coverage meta-data and expanding it usable form. This package
is intended to be used in the coverage tooling that reads data files
emitted from coverage runs. Along with the new decoding package is a
unit test that runs the encode/decode paths together to check to make
sure that "decode(encode(X)) == X".

Updates #51430.

Change-Id: I81d27d8da0b2fcfa5039114a6e35a4b463d19b3c
Reviewed-on: https://go-review.googlesource.com/c/go/+/353454
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Than McIntosh <thanm@google.com>
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internal/coverage: add coverage meta-data encoder

Add a new package with APIs for encoding coverage meta-data. This
provides support for accumulating information about each function
during the compilation process, and then encoding and emitting a
payload for a coverage meta-data symbol.  Not yet connected to the
rest of the coverage machinery (that will appear in a later patch).

Updates #51430.

Change-Id: I61054ce87f205b25fb1bfedaa740fd7425c34de4
Reviewed-on: https://go-review.googlesource.com/c/go/+/353453
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cmd: add a new goexperiment for redesigned code coverage

Add a new "coverageredesign" GOEXPERIMENT (currently off by default),
for gating the use of the new code coverage design/implementation.

Updates #51430.

Change-Id: Ia61da869fcd0d61c6163f734e2fe5e3705f37a91
Reviewed-on: https://go-review.googlesource.com/c/go/+/395894
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Reviewed-by: David Chase <drchase@google.com>
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Reviewed-by: Austin Clements <austin@google.com>

syscall: check if to is nil to prevent panic from WSASendto

to is an optional pointer to sockaddr, as written in the doc:
https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-wsasendto

For #55845

Change-Id: Ia685cec8d9bc9ff313f598db9d2213a1f409757a
Reviewed-on: https://go-review.googlesource.com/c/go/+/434535
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
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internal/saferio: handle potential total size overflow in SliceCap

Before the change, "SliceCap((*int64)(nil), 1<<62)" returns 1<<62.
That's because "uintptr(c)*size" overflows and gives 0 which is less
than the "chunk". SliceCap should return -1 in this case.

Change-Id: I4e99224c8ac0fc72032c6be86d7318d33d083cd8
GitHub-Last-Rev: ca30bcce456d20702e3699822cd4f1c963ef1cec
GitHub-Pull-Request: golang/go#55870
Reviewed-on: https://go-review.googlesource.com/c/go/+/434335
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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os/exec: split parent I/O pipes by whether they are pumped by user code or internal goroutines

The pipes pumped by goroutines can be closed as soon as their
respective goroutines are done.

The pipes pumped by user code, however, are documented to be closed in
Wait. When we add the WaitDelay field, it isn't obvious that we should
terminate the user-pumped pipes when the WaitDelay expires, since Wait
itself isn't going to wait for those user-controlled goroutines to
complete.

(It's a bit more complicated than that because the documentation
currently states that Wait must not be called while the pipes are
being read — but it isn't obvious to me that that advice is entirely
correct.)

For #50436.

Change-Id: I97909c91d2097fb75138a360747168c08609696d
Reviewed-on: https://go-review.googlesource.com/c/go/+/401894
Reviewed-by: Ian Lance Taylor <iant@google.com>
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os/exec: clean up pipe-closing logic

Change the childFiles field to a local variable, since it was
populated during Start and (as far as I can determine) has no purpose
after Start returns.

Rename closeAfterStart and closeAfterWait to childIOFiles and
parentIOPipes respectively. That makes their contents clearer, and also
helps to clarify what should happen on error (when, for example, Wait
shouldn't be called at all).

Use a deferred call instead of individual calls to close child (and,
if necessary, pipe) FDs after Start. That helps to clarify the
invariants around when they are closed, and also makes the function a
bit more robust for future refactoring.

Also nil out the slices containing the file closers so that they can
be collected earlier.

This CL is intended as a pure refactor in preparation for #50436.

Change-Id: I05d13fa91d539b95b84b2ba923c1733f9a6203e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/401834
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internal/cpu: deduplicate arm64 ISAR parsing code

Deduplicate code for parsing system registers - this matches what is done
in golang.org/x/sys/cpu.

Change-Id: If3524eb2e361179c68678f8214230d7068fe4c60
Reviewed-on: https://go-review.googlesource.com/c/go/+/422217
Reviewed-by: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
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internal/cpu: enable arm64 SHA512 detection for freebsd/openbsd

Change-Id: I1f21654b50d7b0cd8e1f854efe2724b72f067449
Reviewed-on: https://go-review.googlesource.com/c/go/+/422216
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Yuval Pavel Zholkover <paulzhol@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

reflect: simplify Value.Comparable

using Type.Comparable to simplify the Value.Comparable,
and return true directly when exit the for loop of kind == array and elements type is interface or array or struct.

Change-Id: Ib0b06a70642ba24c9215c69e7d619960fbeeed90
Reviewed-on: https://go-review.googlesource.com/c/go/+/426457
Auto-Submit: Ian Lance Taylor <iant@google.com>
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cmd/go/internal/mmap: fix build for js/wasm

Even though there isn't much point in building cmd/go for js/wasm given
it relies on executing sub-processes, this change is trivial enough and
makes cmd/go build for js/wasm again.

Fixes #54219

Change-Id: I91e3adec0f31a4e261af89b4cc829711828ac2ed
Reviewed-on: https://go-review.googlesource.com/c/go/+/433480
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

cmd/go/internal, go/build: remove unused errGoBuildWithoutBuild

Last use was removed by CL 240607.

Change-Id: Icfe9e477c6035823bd676a2ff28e1ac202dd991e
Reviewed-on: https://go-review.googlesource.com/c/go/+/431662
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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syscall: check if to is nil to prevent panic from Sendto

Fixes #55845

Change-Id: If30263b7d34829c40e6606846115ec520f351f2c
Reviewed-on: https://go-review.googlesource.com/c/go/+/433504
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cmd/go: avoid internal errors on "go test -testwork"

Fix up the package test harness to avoid errors of the form

  go_test.go:NNN: internal testsuite error: path(".") with no tempdir

when the "-testwork" flag is passed when running "go test".

Fixes #55874.

Change-Id: I76cc39902f51a62cb4cd0da8794b97d620fb4873
Reviewed-on: https://go-review.googlesource.com/c/go/+/434455
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encoding/gob: use saferio.SliceCap when decoding a slice

This avoids allocating an overly large slice for corrupt input.

Change the saferio.SliceCap function to take a pointer to the element type,
so that we can handle slices of interface types. This revealed that a
couple of existing calls were actually incorrect, passing the slice type
rather than the element type.

No test case because the problem can only happen for invalid data. Let
the fuzzer find cases like this.

Fixes #55338

Change-Id: I3c1724183cc275d4981379773b0b8faa01a9cbd2
Reviewed-on: https://go-review.googlesource.com/c/go/+/433296
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Cherry Mui <cherryyz@google.com>
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cmd/compile: use "missing method m" instead of "missing m method"

For #55326

Change-Id: I3d0ff7f820f7b2009d1b226abf701b2337fe8cbc
Reviewed-on: https://go-review.googlesource.com/c/go/+/432635
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Reviewed-by: Robert Griesemer <gri@google.com>

Revert "net/netip: use slice-to-array conversions"

This reverts commit 3dcf6e2c29f533865aad58488b60ae8d819a566e.

Reason for revert: breaks the longtest builders for x/tools

Change-Id: I6b6d5afbe46890b6a59829e3d5ab50d885661696
Reviewed-on: https://go-review.googlesource.com/c/go/+/433478
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
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net/http/httputil: avoid query parameter smuggling

Query parameter smuggling occurs when a proxy's interpretation
of query parameters differs from that of a downstream server.
Change ReverseProxy to avoid forwarding ignored query parameters.

Remove unparsable query parameters from the outbound request

   * if req.Form != nil after calling ReverseProxy.Director; and
   * before calling ReverseProxy.Rewrite.

This change preserves the existing behavior of forwarding the
raw query untouched if a Director hook does not parse the query
by calling Request.ParseForm (possibly indirectly).

Fixes #54663
Fixes CVE-2022-2880

Change-Id: If1621f6b0e73a49d79059dae9e6b256e0ff18ca9
Reviewed-on: https://go-review.googlesource.com/c/go/+/432976
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Damien Neil <dneil@google.com>

net/netip: use slice-to-array conversions

Use slice-to-array conversions in AddrFromSlice and
(*Addr).UnmarshalBinary. This allows allows to use AddrFrom16 and drop
the redundant ipv6Slice helper.

For #46505

Change-Id: I0e3a7d8825ad438115b7f23ee97cc74eec41a826
Reviewed-on: https://go-review.googlesource.com/c/go/+/432735
Reviewed-by: Damien Neil <dneil@google.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

cmd/compile: use "init... cycle" instead of "init... loop" in error messages

For #55326.

Change-Id: Ia3c1124305986dcd49ac769e700055b263cfbd59
Reviewed-on: https://go-review.googlesource.com/c/go/+/432615
Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@google.com>

cmd/compile: handle go.mod error msg reference in noder, not type checker

Currently, for version errors, types2 adds the helpful hint

(-lang was set to go1.xx; check go.mod)

where 1.xx is the respective language version, to the error message.
This requires that the type checker knows that it was invoked by the
compiler, which is done through the Config.CompilerErrorMessages flag.

This change looks for version errors being returned by the type checker
and then adds the hint at that point, external to the type checker.
This removes a dependency on the Config.CompilerErrorMessages. Once
we have removed all dependencies on Config.CompilerErrorMessages we
can remove it.

For #55326.

Change-Id: I1f9b2e472c49fe785a2075e26c4b3d9b8fcdbf4d
Reviewed-on: https://go-review.googlesource.com/c/go/+/432559
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>

cmd: update vendored golang.org/x/tools for multiple error wrapping

Updates vet to permit errors with an Unwrap method returning []error
and multiple %w verbs in fmt.Errorf.

For #53435.

Change-Id: If097715f86c5a03ed606e6d4fb048e17b154b489
Reviewed-on: https://go-review.googlesource.com/c/go/+/433057
Run-TryBot: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Joseph Tsai <joetsai@digital-static.net>

cmd/compile/internal/ir: add missing import to mknode.go

CL 426257 changed ioutil.WriteFile to os.WriteFile but didn't add the
corresponding import for package os.

Change-Id: I7be32138463b44aabc8e36ce353f6dc1376cbe60
Reviewed-on: https://go-review.googlesource.com/c/go/+/433415
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

cmd/compile: update bottomUpVisitor.visit comments

Change-Id: I83a62b15c5946cfe61afc53c2c528aa3a62f815e
Reviewed-on: https://go-review.googlesource.com/c/go/+/429975
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>

text/template/parse: fix confusion about markers near right delims

Fixes #52527.
Fixes #55336.

Change-Id: I8f5c521c693e74451a558788909e7e4ad1cc797a
Reviewed-on: https://go-review.googlesource.com/c/go/+/433036
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>

path/filepath: optimize isReservedName

A linear search through a list of 22 strings takes ~80ns.
A quick check for 3-4 byte strings reduces this check to 2ns
for a vast majority of inputs.
In the event of a name match, the new logic is either just
as fast (for "CON") or 10x faster (for "LPT9").

Change-Id: I412fa73beebd7c81dc95f9ed12c35ca1d5d6baf0
Reviewed-on: https://go-review.googlesource.com/c/go/+/433175
Reviewed-by: Damien Neil <dneil@google.com>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Ian Lance Taylor <iant@google.com>

runtime/pprof: force use of 4-column profiles in pprof memprofile output

Pprof's converter from legacy text format to protobuf format
assumes that if the alloc and inuse stats are equal, then what's
really going on is that the program makes no distinction, and it
reads them as a two-column profile: objects and bytes.

Most of the time, some sampled object has been freed, and alloc != inuse.
In that case, pprof reads the profile as a four-column profile, with
alloc_objects, alloc_bytes, inuse_objects, inuse_bytes.

The 2-column form causes problems in a few ways. One is that if
you are reading the proto form and expect samples with the 4-column
names, they're not there. Another is that pprof's profile merger insists
on having the same number of columns and same names. This means
that

pprof *.memprofile

works most of the time but fails if one of the memory profiles hit
the unlikely condition that alloc == inuse, since now its converted
form differs from the others.

Most programs should simply not be using this output form at all,
but cmd/compile and cmd/link still do, because x/tools/cmd/compilebench
reads some extra values from the text form that we have not yet added
to the proto form.

For the programs still writing this form, the easiest way to avoid the
column collapse issues is to ensure that the header never reports
alloc == inuse. The actual values in the header are ignored by pprof now,
except for the equality check (they should sum to the other values in the
file, so they are technically redundant). Because the actual values are not
used except for the equality check, we could hard-code different values
like 0 and 1, but just in case, to break as little as possible, this CL only
adjusts the values when they would otherwise be equal. In that case it
adds 1 to allocBytes. For most profiles, where alloc != inuse already, there
is no effect at all.

Change-Id: Ia563e402573d0f6eb81ae496645db27c08f9fe31
Reviewed-on: https://go-review.googlesource.com/c/go/+/432758
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>

cmd/internal/objfile: read file/line information for ELF PIE binaries

For PIE binaries, the .gopclntab section doesn't have the usual
name, but .data.rel.ro.gopclntab. Try the relro version as well.
If both failed (e.g. for externally linked PIE binaries), try
runtime.pclntab symbol.

This should make cmd/objdump able to print the file/line
information for PIE binaries.

I attempted to do this a few years ago, but that wasn't enough,
because the pclntab itself contains dynamic relocations which are
not applied by the tool. As of Go 1.18 the pclntab is mostly
position independent and does not contain dynamic relocations, so
this should be possible now.

Fixes #17883.
Updates #46639.

Change-Id: I85dc3d50ffcc1a4b187a349479a6a162de1ab2b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/227483
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
TryBot-Result: Gopher Robot <gobot@golang.org>

cmd/compile/internal/walk: remove reduceSlice

After CL 22425, there're two optimizations for slice expr which are
never applied during walk pass:

s[i:len(s)]
        s[i:j:cap(s)]

The order pass have already rewritten len/cap expression to use autotmp,
thus the same safe expression check will never fire. The code can now be
simplified by moving the only case left from reduceSlice to walkSlice,
then removing reduceSlice entirely.

Passes toolstash-check.

Change-Id: Ia8cfb15c8e96c186a214c17b42d0fee51b0d3a1c
Reviewed-on: https://go-review.googlesource.com/c/go/+/432695
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>

cmd/go: omit VCS stamping during bootstrap

cmd/dist can't easily hard-code -buildvcs=false because not all
versions of cmd/go supported for bootstrapping recognize that flag.

However, we don't want to stamp the bootstrap binaries: the stamping
is redundant with the VERSION file writted during bootstrapping (which
is why it is normally omitted for standard-library packages and
commands), and it may also interfere with building the Go repo from a
source tarball or zip file.

Fixes #54852.

Change-Id: If223f094af137c4c202d6bf622619bd2da397ec4
Reviewed-on: https://go-review.googlesource.com/c/go/+/432435
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

cmd/compile/internal/syntax: remove TypeList syntax in comment

Change-Id: Ic4df6a8e198b069a9f3a28710fa40f29bd658b06
GitHub-Last-Rev: 51040eb5e53f4cf0238cb0b7876d1ee612a924ef
GitHub-Pull-Request: golang/go#55345
Reviewed-on: https://go-review.googlesource.com/c/go/+/432795
Run-TryBot: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

crypto/tls: convert Conn.activeCall to atomic type

Change-Id: I5b063070a17bdeed57e73bfb76125b94268b3bc9
Reviewed-on: https://go-review.googlesource.com/c/go/+/426088
Run-TryBot: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>

all: tidy std module

Change-Id: I7350a608a198073673fb9b7e9b91dae6f1c861b7
Reviewed-on: https://go-review.googlesource.com/c/go/+/432495
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Damien Neil <dneil@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Damien Neil <dneil@google.com>

net/http: add tracing to TestTransportReuseConnection_Gzip_*

These tests are flaky; add some additional logging in hopes
it will aid in debugging.

For #53373

Change-Id: I971a2815f50932a9700ef8c2f684c5416951e6de
Reviewed-on: https://go-review.googlesource.com/c/go/+/432375
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>