Robert Griesemer [Tue, 26 Oct 2021 00:22:55 +0000 (17:22 -0700)]
cmd/compile/internal/types2: clean up asT converters (step 1 of 2)
This CL changes the convenience converters asT to use under instead
of optype. To make sure the effect is well understood, in a first
step, all asT functions are renamed to toT so that we can see which
call sites are affected. In almost all places, the change is what we
want. In some places we may get more conservative behavior (which is
easy to relax if need be). In some places (function calls through a
type parameter, append built-in) we now use singleUnder instead, for
a more general behavior, matching other primary expressions or built-
ins.
This change removes the last use of optype and thus also theTop and
top, all of which have been deleted from the code.
The next CL renames the toT converters back to their asT form.
Change-Id: I35d1ad866ce46de175a055b36ef577d99bb9de22
Reviewed-on: https://go-review.googlesource.com/c/go/+/358597
Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
Robert Griesemer [Fri, 22 Oct 2021 16:49:15 +0000 (09:49 -0700)]
cmd/compile/internal/types2: generalize assignability to generic types
Similar to conversions, handle ordinary cases first, followed by
type-by-type assignability tests in case of type parameters with
specific types in their type sets.
Add a new class of type checker tests, in testdata/spec, which
I hope we can populate over time with tests following the spec
organization. Moved the conversions.go2 tests in the same dir.
Change-Id: Iac253ae375c08022bdc39e92e3951ec3f509e432
Reviewed-on: https://go-review.googlesource.com/c/go/+/357917
Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
Robert Griesemer [Mon, 25 Oct 2021 16:13:16 +0000 (09:13 -0700)]
cmd/compile/internal/types2: clarify is/underIs semantics and implementation
The behavior of is/underIs was murky with the presence of a top type term
(corresponding to a type set that is not constrained by any types, yet the
function argument f of is/underIs was called with that term).
Change is/underIs to call f explicitly for existing specific type terms,
otherwise return the result of f(nil). Review all uses of is/underIs and
variants.
This makes the conversion code slightly more complicated because we need
to explicitly exclude type parameters without specific types; but the
code is clearer now.
Change-Id: I6115cb46f7f2a8d0f54799aafff9a67c4cca5e30
Reviewed-on: https://go-review.googlesource.com/c/go/+/358594
Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
Katie Hockman [Fri, 22 Oct 2021 19:59:15 +0000 (15:59 -0400)]
internal/fuzz: don't deflake coverage found while fuzzing
Previously, the worker would attempt to deflake
an input that was reported to have caused new
coverage. The chances of a flake causing new
coverage seem pretty low to me, and even if it
was a flake that caused it, adding that input to
the cache doesn't seem like a bad thing. The
input is already going to be deflaked during
minimization anyway. If by some off-chance the
code is causing a lot of flaky coverage
increases, and the user doesn't want minimization
to occur, then setting -fuzzminimizetime=1x will
deflake in the way they want without minimizing.
This can be documented as needed.
This fixes a bug where the mem.header().count
could have been one too large if an unrecoverable
crash occured while deflaking an input that
caused code coverage.
Fixes #49047
Change-Id: Ibdf893d7a89a46dd700702afb09e35623615390e
Reviewed-on: https://go-review.googlesource.com/c/go/+/358094
Trust: Katie Hockman <katie@golang.org>
Run-TryBot: Katie Hockman <katie@golang.org>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Julie Qiu <julie@golang.org> Reviewed-by: Roland Shoemaker <roland@golang.org> Reviewed-by: Bryan C. Mills <bcmills@google.com>
Robert Findley [Mon, 25 Oct 2021 17:26:54 +0000 (13:26 -0400)]
go/types: remove a stale comment
Clean up a comment that was deleted in types2 in CL 353135.
Change-Id: If339efa133e2a3d1eaa3b1e69458471677018261
Reviewed-on: https://go-review.googlesource.com/c/go/+/358517
Trust: Robert Findley <rfindley@google.com>
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Russ Cox [Mon, 11 Oct 2021 15:57:24 +0000 (11:57 -0400)]
cmd: move internal/str back to cmd/go
cmd/go is not subject to all the same restrictions as most of cmd.
In particular it need not be buildable with the bootstrap toolchain.
So it is better to keep as little code shared between cmd/go and
cmd/compile, cmd/link, cmd/cgo as possible.
cmd/internal/str started as cmd/go/internal/str but was moved
to cmd/internal in order to make use of the quoted string code.
Move that code to cmd/internal/quoted and then move the rest of
cmd/internal/str back to cmd/go/internal/str.
Cholerae Hu [Wed, 27 Oct 2021 03:41:47 +0000 (11:41 +0800)]
cmd/go: add darwin/arm64 in the list of supported systems in help message
Fixes #49173.
Change-Id: I71270b4ff7e9ede3cdfa5946b73142a731752adf
Reviewed-on: https://go-review.googlesource.com/c/go/+/358901 Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com> Reviewed-by: Keith Randall <khr@golang.org>
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
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Andy Pan [Tue, 26 Oct 2021 01:15:17 +0000 (09:15 +0800)]
internal/poll: improve the padding calculation inside struct splicePipe
Updates #48968 and CL 358114
Change-Id: Ic68b4c5420c1c32f78b56874b53d717fa9af1f74
Reviewed-on: https://go-review.googlesource.com/c/go/+/358734
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Cuong Manh Le [Mon, 25 Oct 2021 07:16:53 +0000 (14:16 +0700)]
cmd/compile: fix generic type handling when crawling inline body
For base generic type that is written to export file, we need to mark
all of its methods, include exported+unexported methods, as reachable,
so they can be available for instantiation if necessary. But markType
only looks for exported methods, thus causing the crash in #49143.
To fix this, we introduce new method p.markGeneric, to mark all methods
of the base generic type.
This issue has happend for a while (maybe since we add generic
import/export during go1.18 cycle), and was un-intentionally "fixed" in
CL 356254, when we agresssively call p.markEmbed(t). CL 357232 fixed
that wrong agressive behavior, thus reproduce the bug on tip.
Fixes #49143
Change-Id: Ie64574a05fffb282e9dcc8739df4378c5b6b0468
Reviewed-on: https://go-review.googlesource.com/c/go/+/358814
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Dan Scales <danscales@google.com>
Ian Lance Taylor [Tue, 26 Oct 2021 16:01:34 +0000 (09:01 -0700)]
embed/internal/embedtest: use parenthesized vars for one test
The gofrontend code mishandled this case, so add it to the test.
Change-Id: I183b8fab57552320b04c4826c590b7c6d36b6548
Reviewed-on: https://go-review.googlesource.com/c/go/+/358836
Trust: Ian Lance Taylor <iant@golang.org>
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crypto/elliptic: use a const string for precomputed P256 table
Const strings can be marked readonly. This is particularly
important for this relatively large table (88kb).
This is a follow-up to CL 315189.
The generation script is a bit awkward. It needs access to crypto/elliptic
internals, but also needs to be package main. Work around this by
exporting those internals with the "tablegen" build tag.
This requires changing the function signature at the Go-asm bridge.
As long as we're here, shrink the point argument type as well;
the net result is three fewer words of params.
Michael Pratt [Wed, 4 Aug 2021 21:33:50 +0000 (17:33 -0400)]
runtime: handle async fatal signals in VDSO
If we receive an async signal while running in the VDSO, such as a
SIGABRT or SIGSEGV sent from another process, we fail to print the
stacktrace with "runtime: unknown pc <vdso PC>".
We already have machinery to handle SIGPROF in the VDSO, but it isn't
hooked up for other signals. Add it to the general signal traceback
path.
This case is covered by TestSegv by making the test more strict w.r.t.
accepted output.
Fixes #47537
Change-Id: I755585f70e0c23e207e135bc6bd2aa68298e5d24
Reviewed-on: https://go-review.googlesource.com/c/go/+/339990
Trust: Michael Pratt <mpratt@google.com>
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Michael Pratt [Wed, 4 Aug 2021 15:24:28 +0000 (11:24 -0400)]
runtime: fix cgo signals detection
CL 64070 removed lockOSThread from the cgocall path, but didn't update
the signal-in-cgo detection in sighandler. As a result, signals that
arrive during a cgo call are treated like they arrived during Go
execution, breaking the traceback.
Update the cgo detection to fix the backtrace.
Fixes #47522
Change-Id: I61d77ba6465f55e3e6187246d79675ba8467ec23
Reviewed-on: https://go-review.googlesource.com/c/go/+/339989
Trust: Michael Pratt <mpratt@google.com>
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Keith Randall [Thu, 9 Jul 2020 16:13:34 +0000 (09:13 -0700)]
sync/atomic: use a better first-store-in-progress marker
Unlike what the comment says, the GC can see this pointer.
Might as well make it a real pointer, even though ^uintptr(0)
isn't currently causing problems.
Removed the comment about GC not seeing the pointer.
Change-Id: I04bc1fd4848698bec6afb79bd5fda671dfc9a073
Reviewed-on: https://go-review.googlesource.com/c/go/+/241661
Run-TryBot: Keith Randall <khr@golang.org> Reviewed-by: Colin Arnott <colin@urandom.co.uk> Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
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Change-Id: I83690f7b4d4dc57557963100e9a2560ff343f3e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/307813
Trust: Michael Pratt <mpratt@google.com>
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Dan Scales [Tue, 19 Oct 2021 01:11:48 +0000 (18:11 -0700)]
cmd/compile: clean up the switch statements in (*genInst).node()
There were two main outer switch statements in node() that can just be
combined. Also, for simplicity, changed an IsCmp() conditional into just
another case in the switch statement.
Also, the inner OCALL switch statement had a bunch of fairly duplicate
cases. Combined the cases that all had no special semantics, into a
single default case calling transformCall().
In the OCALL case in dictPass(), got rid of a check for OFUNCINST (which
will always have been removed by this point). Also, eliminated an assert
that could cause unneded failures. transformCall() should always be
called if the node op is still OCALL, so no need to assert on the ops of
call.X.
Added an extra test in issue47078.go, to explicitly check for case where
the X argument of a call is a DOTTYPE.
Change-Id: Ifb3f812ce12820a4ce08afe2887f00f7fc00cd2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/358596
Trust: Dan Scales <danscales@google.com>
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TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
Robert Findley [Tue, 26 Oct 2021 13:47:18 +0000 (09:47 -0400)]
cmd/compile/internal/typecheck: update doc for the 1.18 export format
Update the documentation in iexport.go to use the word 'Constraint'
rather than 'Bound', and to account for recent changes to the export
format.
Change-Id: I83fbcd336d5f865af804bc8bef4f5d997cd9f325
Reviewed-on: https://go-review.googlesource.com/c/go/+/358547
Trust: Robert Findley <rfindley@google.com>
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Dmitri Shuralyov [Tue, 26 Oct 2021 04:27:27 +0000 (00:27 -0400)]
all: update vendored golang.org/x/tools
Pull in CL 358034 (and some more changes with passing tests) with:
go get -d golang.org/x/tools@f916b54
go mod tidy
go mod vendor
This teaches x/tools/cmd/bundle and the package loader it uses about
the new export data version.
Fixes #49159.
Change-Id: Icc36e77e602b1cd2da03708f20d05a66fcf693cd
Reviewed-on: https://go-review.googlesource.com/c/go/+/358620
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
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Paul E. Murphy [Tue, 10 Aug 2021 14:50:56 +0000 (09:50 -0500)]
cmd/internal/obj/ppc64: fix usage of CR bit arguments
CR bits and CR fields should be treated separately. Some instructions
modify an entire CR, a CR field, or a single CR bit.
Add a new argument class for CR bits, and teach the assembler the
recognize them as names like CR0LT or CR2SO, and update the CR
bit logic instructions to use them. They will no longer accept
register field (CRn) type arguments.
Fixes #46422
Change-Id: Iaba127d88abada0c2a49b8d3b07a976180565ae4
Reviewed-on: https://go-review.googlesource.com/c/go/+/357774
Run-TryBot: Paul Murphy <murp@ibm.com>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com>
Tobias Klauser [Mon, 25 Oct 2021 05:48:12 +0000 (07:48 +0200)]
syscall: add utimensat libc wrapper on darwin
Add utimensat as a wrapper around the libc function of the same name.
utimensat was added in macOS 10.13 which is the minimum supported
release since Go 1.17 dropped support for macOS 10.12.
This also allows to drop the fallback to setattrlistTimes which was
used to set timestamps with nanosecond resolution before utimensat could
be used, see #22528 and CL 74952.
Updates #22528
Change-Id: I87b6a76acf1d642ceede9254f7d9d06dddc3fd71
Reviewed-on: https://go-review.googlesource.com/c/go/+/358274
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
fanzha02 [Mon, 4 Jan 2021 09:53:37 +0000 (17:53 +0800)]
runtime, runtime/asan: add asan runtime support
These are the runtime support functions for letting Go code interoperate
with the C/C++ address sanitizer. Calls to asanread/asanwrite are now
inserted by the compiler with the -asan option. Calls to
asanunpoison/asanpoison will be from other runtime functions in a
subsequent CL.
Updates #44853.
Change-Id: I9e8fc0ce937828bc7f4a8b6637453ddc3862c47b
Reviewed-on: https://go-review.googlesource.com/c/go/+/298613
Trust: fannie zhang <Fannie.Zhang@arm.com>
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Fannie Zhang [Wed, 6 Jan 2021 08:57:44 +0000 (08:57 +0000)]
cmd/go: add -asan option
The -asan option compiles Go code to use the address sanitizer. This is
intended for use when linking with C/C++ code compiled with -fsanitize=address.
When memory blocks are passed back and forth between C/C++ and Go, code in
both languages will agree as to whether the memory is validly allocated or not,
and will report errors for any use of invalid memory.
fanzha02 [Wed, 17 Mar 2021 06:52:27 +0000 (14:52 +0800)]
cmd/internal/obj/arm64: add a restriction on move constant instructions
For MOVK/MOVN/MOVZ instructions, the assembler does not accept zero
shifts, and the CL 275812 added the error check. This CL adds this
restriction to the document.
Change-Id: I8818d76ca2f11dade2307f3678ca521f4e64d164
Reviewed-on: https://go-review.googlesource.com/c/go/+/312210
Trust: fannie zhang <Fannie.Zhang@arm.com>
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Gusted [Mon, 25 Oct 2021 23:45:44 +0000 (01:45 +0200)]
container/list: remove unnecessary code
Remove a unnecessary statement in the test function, the variables
aren't checked afterwards. Also remove return statements in helper
functions and remove the declaration that a the helper function return a
value. The return value isn't used in the current state of code
Change-Id: I5bc384104c1002c4138e0894938778ae9710ce4d
Reviewed-on: https://go-review.googlesource.com/c/go/+/358714
Run-TryBot: Robert Griesemer <gri@golang.org>
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Cherry Mui [Mon, 25 Oct 2021 16:18:40 +0000 (12:18 -0400)]
cmd/internal/obj/riscv: don't split ADD to SP to two adds
When adding a large constant to a register we generate two adds,
we may generate two ADD instructions if the constant does not fit
in one ADD but does fit in two. This is generally fine except that
if the target register is SP (such as in function prologues or
epilogues for functions with large frames), this creates an
intermediate state that the SP is not 0 nor the full frame size.
For signal safety (preemption signal and profiling signal) we
require that the frame is either not created at all or fully
created, meaning that the SP must be written in a single
instruction. Splitting to two adds breaks the requirement. So not
splitting it.
(We could mark such instructions not async-preemptible. But
profiling signal can still cause problems.)
(We could generate "ADD $c1, SP, Rtmp; ADD $c2; Rtmp; SP" to save
an instruction if that is desired, while still ensuring that SP
is written in a single instruction.)
Change-Id: I5cf38a6a028afe01aa3b6eeb163487bbd504b64f
Reviewed-on: https://go-review.googlesource.com/c/go/+/358436
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Dan Scales [Tue, 19 Oct 2021 20:28:54 +0000 (13:28 -0700)]
cmd/compile: update the export version for generics
Bump the export version to a new value iexportVersionGo1_18 (2). This
will give a better error message when old compilers/tools encounter the
new export format (that includes parameterized types and functions).
We are also making a breaking change in the format:
- a 'kind' byte is added to constant values
Also updated tinter() to pass the implicit bit through during type
substitution.
Tested that all tests still pass if the iexportVersionCurrent is changed
back to 1 in typecheck/iexport.go, iimporter/iimport.go, and
gcimporter/iimport.go
Updates #47654
Change-Id: I1dbeb167a97f6c7e0b7e0c011d6bada5db312b36
Reviewed-on: https://go-review.googlesource.com/c/go/+/357049
Run-TryBot: Dan Scales <danscales@google.com>
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fanzha02 [Mon, 4 Jan 2021 09:14:35 +0000 (17:14 +0800)]
cmd/compile: add -asan option
The -asan option causes the compiler to add instrumentation for the
C/C++ address sanitizer. Every memory read/write will be replaced
by a call to asanread/asanwrite.
This CL also inserts asan instrumentation during SSA building.
This CL passes tests but is not usable by itself. The actual
implementation of asanread/asanwrite in the runtime package, and
support for -asan in the go tool and tests, will follow in subsequent
CLs.
Updates #44853.
Change-Id: Ia18c9c5d5c351857420d2f6835f0daec2ad31096
Reviewed-on: https://go-review.googlesource.com/c/go/+/298611
Trust: fannie zhang <Fannie.Zhang@arm.com>
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Ian Lance Taylor [Fri, 22 Oct 2021 21:19:34 +0000 (14:19 -0700)]
internal/poll: avoid tiny allocator for splicePipe
We want to set a finalizer on splicePipe, so make it large enough to
not use the tiny allocator. Otherwise the finalizer will not run until
the rest of the tiny allocation can be freed. This only matters on
32-bit systems.
Fixes #48968
Change-Id: I8eb3c9f48fdccab7dc79c5b918d4257b6151ee91
Reviewed-on: https://go-review.googlesource.com/c/go/+/358114
Trust: Ian Lance Taylor <iant@golang.org>
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Keith Randall [Fri, 22 Oct 2021 01:28:50 +0000 (18:28 -0700)]
cmd/link: escape % characters in symbols when reporting errors
Generic function symbols sometimes have % in them, like:
main.B2[%2eshape.string_0].m2·f
Which confuses this code because it doesn't esacpe % when
using this string as a format string, instead of a format argument.
Or could we get rid of the . -> %2e rewrite somehow?
I think it comes from LinkString.
Change-Id: I3275501f44cf30485e9d4577e0dfa77996d4939e
Reviewed-on: https://go-review.googlesource.com/c/go/+/357837
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Keith Randall [Fri, 22 Oct 2021 01:09:07 +0000 (18:09 -0700)]
cmd/compile: revert most of CL 349169
The method of using references to dictionaries to hold methods
live during linker deadcode elimination wasn't working very well.
I implemented a new scheme in the CL below this, so this CL strips
out the old method.
The new method has the added benefit of having 0 runtime overhead
(unlike the stuff we're ripping out here, which does have a small overhead).
Update #48047
Change-Id: I68ac57119792d53c58f1480f407de6ab2bb53211
Reviewed-on: https://go-review.googlesource.com/c/go/+/357836
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Change-Id: I1ff5f24b5540c3e80c4b35be8215a1c378952274
Reviewed-on: https://go-review.googlesource.com/c/go/+/357894
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To capture the fact that a method was called on a generic interface,
so we can make sure the linker doesn't throw away any implementations
that might be the method called.
See the comment in reflect.go for details.
Fixes #49049
Change-Id: I0be74b6e727c1ecefedae072b149f59d539dc1e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/357835
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Richard Musiol [Sun, 24 Oct 2021 10:28:18 +0000 (12:28 +0200)]
cmd/link: increase reserved space for passing env on wasm
On wasm, the wasm_exec.js helper passes the command line arguments and
environment variables via a reserved space in the wasm linear memory.
Increase this reserved space from 4096 to 8192 bytes so more environment
variables can fit into the limit.
Later, after https://golang.org/cl/350737 landed, we can switch to the
WASI interface for getting the arguments and environment. This would
remove the limit entirely.
Fixes #49011
Change-Id: I48a6e952a97d33404ed692c98e9b49c5cd6b269b
Reviewed-on: https://go-review.googlesource.com/c/go/+/358194
Trust: Richard Musiol <neelance@gmail.com>
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com>
Cherry Mui [Mon, 25 Oct 2021 15:51:25 +0000 (11:51 -0400)]
cmd/compile: don't clobber LR for tail calls
When doing a tail call the link register is live as the callee
will directly return to the caller (of the function that does the
tail call). Don't allocate or clobber the link register.
Fixes #49032.
Change-Id: I2d60f2354e5b6c14aa285c8983a9786687b90223
Reviewed-on: https://go-review.googlesource.com/c/go/+/358435
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com> Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Robert Findley [Tue, 19 Oct 2021 22:40:27 +0000 (18:40 -0400)]
cmd/compile/internal/typecheck: record whether an interface is implicit
In preparation for capturing the implicit interface bit in export data,
thread through the IsImplicit property from types2 into typecheck.
Change-Id: I9b46fe73de102935a127e6ececaacd76738b557e
Reviewed-on: https://go-review.googlesource.com/c/go/+/357109
Trust: Robert Findley <rfindley@google.com>
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Robert Findley [Thu, 21 Oct 2021 22:36:14 +0000 (18:36 -0400)]
go/types: remove subscripts from type parameter names
Now that we've removed the necessity for subscripts in importers, we can
effectively eliminate them from the the type parameter API by removing
them from the type string.
Change-Id: Ic4491b0dea27b0e0ce2d0636dccfaf05168ef9e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/357814
Trust: Robert Findley <rfindley@google.com>
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TryBot-Result: Go Bot <gobot@golang.org>
CL 357649 fixes inlining labeled FOR/RANGE loops,
we should do same translation for inlined SWITCH's label
Fixes #49145
Change-Id: I9a6f365f57e974271a1eb279b38e81f9b5148788
Reviewed-on: https://go-review.googlesource.com/c/go/+/358315
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Dan Scales <danscales@google.com>
Michael Pratt [Mon, 18 Oct 2021 22:34:24 +0000 (18:34 -0400)]
testing: skip extra -count iterations if there are no tests
When running benchmarks with high -count and no tests (either at all or
filtered with -run), the time for runTests to check for tests -count
times can add a significant delay to starting benchmarks.
To avoid this delay, make runTests bail out on the second iteration if
the first found no tests to run. We expect the same tests to run every
time, so there is no reason to duplicate work.
One caveat: the testing docs do not explicitly require the same subtests
to be run on every call, so this could break tests that depend on
multiple runs to actually run all tests. I consider such tests invalid,
but some may exist.
Fixes #49050
Change-Id: I7b34f3832b31493cc089ee0555e231f4dc690154
Reviewed-on: https://go-review.googlesource.com/c/go/+/356669
Trust: Michael Pratt <mpratt@google.com>
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Robert Griesemer [Sat, 23 Oct 2021 23:39:32 +0000 (16:39 -0700)]
cmd/compile/internal/types2: better error messages for empty type sets
- change _TypeSet.hasTerms() to report if a type set has actual types
(excluding a "universe" term)
- handle empty type set type arguments correctly
- bring comments up-to-date in Checker.satisfies
Change-Id: I87f9a1096ebb21a1b08c87a9b59f400f3bc2f040
Reviewed-on: https://go-review.googlesource.com/c/go/+/358175
Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
Austin Clements [Thu, 21 Oct 2021 15:11:13 +0000 (11:11 -0400)]
testing: reference benchmark format spec
This updates the testing package documentation to reference the
specification for the benchmark format, and points users to our
standard tools for working with benchmark data. (It's somewhat
remarkable how widely used benchstat appears to be given that we don't
mention it anywhere!)
Change-Id: Idbb4416d2fde9606ea7e6c15595f3b9e6a38f3b0
Reviewed-on: https://go-review.googlesource.com/c/go/+/357589
Trust: Austin Clements <austin@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Olivier Wulveryck [Mon, 31 May 2021 06:03:57 +0000 (08:03 +0200)]
image/draw: improve performances if mask is *image.Alpha
The existing DrawMask method is generic and is therefore calling the At().RGBA() method for every pixel of the mask and the source.
Do a specific implementation when the mask is *image.Alpha (which is
common) and use use the PixOffset method to increase performances.
Cuong Manh Le [Sun, 24 Oct 2021 06:46:54 +0000 (13:46 +0700)]
cmd/compile: factor out code to remove phi argument
CL 358117 fixed a bug that Phi's argument wasn't updated correctly after
removing a predecessor of Block. This CL factor out the code that
updates phi argument into a Block's method, so it's easier to use,
maintain and hopefully prevent that kind of bug in the future.
Change-Id: Ie9741e19ea28f56860425089b6093a381aa10f5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/357964
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: Keith Randall <khr@golang.org>
Keith Randall [Sat, 23 Oct 2021 17:16:41 +0000 (10:16 -0700)]
cmd/compile: fix fuse pass to do CFG surgery correctly
removePred and removeArg do different things. removePred moves the last
predecessor to index k, whereas removeArg slides all the args k or
greater down by 1 index.
Kind of unfortunate different behavior in things named similarly.
Fixes #49122
Change-Id: I9ae409bdac744e713f4c121f948e43db6fdc8542
Reviewed-on: https://go-review.googlesource.com/c/go/+/358117
Trust: Keith Randall <khr@golang.org>
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Robert Griesemer [Wed, 20 Oct 2021 22:06:35 +0000 (15:06 -0700)]
cmd/compile/internal/types2: factor out slice elem computation for copy built-in
Implement singleUnder[String] which determines a single underlying type
for a given type: either the underlying type, or the single underlying
type for a type parameter, if it exists. Use singleUnder[String] instead
of optype for copy built-in.
This CL removes a dependency on optype and also makes the copy built-in
slighty more general for generic arguments (the source argument may be
constrained by a slice or string simultaneously).
Change-Id: Ia329e96afc69a09d2ca3b1f82fe712d4f7ba1d9f
Reviewed-on: https://go-review.googlesource.com/c/go/+/357413
Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
Robert Griesemer [Fri, 22 Oct 2021 23:57:58 +0000 (16:57 -0700)]
cmd/go: update test script for reformatted error message (fix long builds)
TBR=iant
Change-Id: Ic72af52e5ff8d28f8102c07b03e4930df61445ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/358115
Trust: Robert Griesemer <gri@golang.org>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
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Cuong Manh Le [Fri, 22 Oct 2021 10:05:35 +0000 (17:05 +0700)]
cmd/compile: prevent compiling closures more than once
Since CL 282892, functions are always compiled before closures. To do
that, when walking the closure, it is added to its outer function queue
for scheduling compilation later. Thus, a closure may be added to queue
more than once, causing the ICE dues to being compiled twice.
To fix this, catching the re-walking of the closure expression and do
not add it to the compilation queue.
Fixes #49029
Change-Id: I7d188e8f5b4d5c4248a0d8e6389da26f1084e464
Reviewed-on: https://go-review.googlesource.com/c/go/+/357960
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: Keith Randall <khr@golang.org>
fanzha02 [Mon, 4 Jan 2021 08:23:01 +0000 (16:23 +0800)]
cmd/link: add -asan option
The -asan option causes the linker to link against the runtime/asan
package in order to use the C/C++ address sanitizer.
This CL passes tests but is not usable by itself. The actual
runtime/asan package, and support for -asan in the go tool and the
compiler, and tests, are in separate CLs.
Updates #44853.
Change-Id: Ifc6046c1f75ba52777cbb3d937a4b66e91d5798d
Reviewed-on: https://go-review.googlesource.com/c/go/+/298610
Trust: fannie zhang <Fannie.Zhang@arm.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Robert Griesemer [Wed, 20 Oct 2021 01:09:30 +0000 (18:09 -0700)]
cmd/compile/internal/types2: more detailed error messages for generic conversions
- slightly refactor convertibleTo and convertibleToImpl
- provide ability to return a conversion failure cause
- add detailed cause for generic conversions
For #47150.
Change-Id: Ie97d89be0234414ef4df22a6920e18acc944a102
Reviewed-on: https://go-review.googlesource.com/c/go/+/357249
Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
Robert Griesemer [Wed, 20 Oct 2021 20:12:43 +0000 (13:12 -0700)]
cmd/compile/internal/types2: reduce output when describing type parameters
There's no need to say "type parameter" for a type parameter. The
name is sufficient (they are always named), and the prose is followed
by "constrained by".
Change-Id: I98df8caa1432b8b7a874e58da6e3ed6be102b4a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/357410
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
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Cuong Manh Le [Thu, 21 Oct 2021 07:31:40 +0000 (14:31 +0700)]
cmd/compile: only look for struct type when crawling inline body
CL 356254 fixed crawling of embeddable types during inline. However, we
are too agressive, since when we call markEmbed for every type seen
during inlining function body. That leads to false positive that for a
non-embedded type, its unexported methods are also marked inline.
Instead, we should only look at struct type that we seen during inlining
function body, and calling markEmbed for all of its embedded fields.
Fixes #49094
Change-Id: I6ef9a8bf1fc649ec6bf75e4883f6031ec8560ba1
Reviewed-on: https://go-review.googlesource.com/c/go/+/357232
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: Matthew Dempsky <mdempsky@google.com>
Robert Findley [Thu, 21 Oct 2021 22:59:10 +0000 (18:59 -0400)]
go/types, types2: add the Interface.MarkImplicit method
Add a new interface method, MarkImplicit, to allow marking interfaces as
implicit from outside the type-checker. This is necessary so that we can
capture the implicit bit in export data, and use it from importers.
For #48424
For #49040
Change-Id: I999aba2a298f92432326d7ccbd87fe133a2e1a72
Reviewed-on: https://go-review.googlesource.com/c/go/+/357796
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>
This introduces a number of new classifications which will make it
easier to generate functions to assemble the new instructions of
ISA 3.1, and potentially earlier versions.
No code generation changes should occur as a result of these. These
allow finer control over how an opcode is matched to an optab entry.
Literal values are now classified based on the smallest number of bits
needed to encode, and matching rules will accept a literal if it
can be zero/sign extended to fit a larger literal class.
Likewise, support classifying even register numbers for GPR, VSX, and
FPR instructions. Some instructions require and even/odd register pair,
and these are usually represented by specifying the even register, and
similarly encoded.
Likewise, add a unit test for the argument classifier function (aclass).
This caught an off-by-one bug in aclass which is also fixed.
Updates #44549
Change-Id: Ia03013aea8b56c4d59b7c3812cdd67ddb3b720b9
Reviewed-on: https://go-review.googlesource.com/c/go/+/350152 Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Dan Scales [Wed, 20 Oct 2021 20:56:15 +0000 (13:56 -0700)]
cmd/compile: fix inlining of labeled for loops
There is already a mechanism using inlgen to rename labels insided
inlined functions so that they are unique and don't clash with loops in
the outer function. This is used for OLABEL and OGOTO. Now that we are
doing inlining of OFOR loops, we need to do this translation for OBREAK,
OCONTINUE, and OFOR. I also added the translation for ORANGE loops, in
anticipation of a CL that will allow inlining of ORANGE for loops.
Fixes #49100
Change-Id: I2ccddc3350370825c386965f4a1e4bc54d3c369b
Reviewed-on: https://go-review.googlesource.com/c/go/+/357649
Run-TryBot: Dan Scales <danscales@google.com>
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Trust: Dan Scales <danscales@google.com>
Michael Anthony Knyszek [Thu, 8 Apr 2021 22:01:13 +0000 (22:01 +0000)]
runtime: detangle gcPaceScavenger from the pacer
Currently gcPaceScavenger is called by gcControllerState.commit, but it
manipulates global state which precludes testing. This change detangles
the two.
Change-Id: I10d8ebdf426d99ba49d2f2cb4fb64891e9fd6091
Reviewed-on: https://go-review.googlesource.com/c/go/+/309272 Reviewed-by: Michael Pratt <mpratt@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
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Michael Anthony Knyszek [Thu, 8 Apr 2021 21:07:02 +0000 (21:07 +0000)]
runtime: formalize and fix gcPercent synchronization
Currently gcController.gcPercent is read non-atomically by
gcControllerState.revise and gcTrigger.test, but these users may
execute concurrently with an update to gcPercent.
Although revise's results are best-effort, reading it directly in this
way is, generally speaking, unsafe.
This change makes gcPercent atomically updated for concurrent readers
and documents the complete synchronization semantics.
Because gcPercent otherwise only updated with the heap lock held or the
world stopped, all other reads can remain unsynchronized.
For #44167.
Change-Id: If09af103aae84a1e133e2d4fed8ab888d4b8f457
Reviewed-on: https://go-review.googlesource.com/c/go/+/308690
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Michael Pratt <mpratt@google.com>
Robert Findley [Thu, 21 Oct 2021 17:23:29 +0000 (13:23 -0400)]
go/types, types2: always return an underlying type from optype
Optype should never return a defined type.
Change-Id: I37b29e0c958e127e75e834e71d6392ea80827773
Reviewed-on: https://go-review.googlesource.com/c/go/+/357694
Trust: Robert Findley <rfindley@google.com>
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Amelia Downs [Mon, 18 Oct 2021 16:36:07 +0000 (12:36 -0400)]
net/url: add testable examples for Values funcs
Change-Id: Id71f3d8d7c1ef7910d5d9497167dc677f2f0a2ef
Reviewed-on: https://go-review.googlesource.com/c/go/+/356535
Trust: Damien Neil <dneil@google.com>
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Damien Neil <dneil@google.com>
Amelia Downs [Mon, 18 Oct 2021 17:06:58 +0000 (13:06 -0400)]
net/url: add testable examples for url pkg funcs
Change-Id: I61011b75128478aa50308d84f4cba23b3e241b3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/356536
Trust: Damien Neil <dneil@google.com>
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Damien Neil <dneil@google.com>
Archana R [Tue, 19 Oct 2021 09:11:46 +0000 (04:11 -0500)]
internal/bytealg: fix Separator length check for Index/ppc64le
Modified condition in the ASM implementation of indexbody to
determine if separator length crosses 16 bytes to BGT from BGE
to avoid incorrectly crossing a page.
Also fixed IndexString to invoke indexbodyp9 when on the POWER9
platform
Change-Id: I0602a797cc75287990eea1972e9e473744f6f5a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/356849
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
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Trust: Keith Randall <khr@golang.org>
Lynn Boger [Thu, 14 Oct 2021 17:55:43 +0000 (12:55 -0500)]
cmd/compile/internal/ssa/gen: eliminate unnecessary neg and xori on PPC64
This adds a few rules to PPC64 to eliminate some instructions:
- when an isel is used to generate a boolean value based on a
condition and followed by an xori to flip the result, it can
instead flip the operands in the isel and avoid the xori.
= when a neg follows a sub the operands to the sub can be
swapped and the neg avoided.
There are several opportunities in reflect.DeepEqual to omit
xori which improves some of its benchmarks by as much as
5%
Michael Anthony Knyszek [Mon, 18 Oct 2021 23:14:20 +0000 (23:14 +0000)]
runtime: retype mheap.reclaimCredit as atomic.Uintptr
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
add mheap.reclaimCredit \
// reclaimCredit is spare credit for extra pages swept. Since \
// the page reclaimer works in large chunks, it may reclaim \
// more than requested. Any spare pages released go to this \
// credit pool. \
reclaimCredit_ atomic.Uintptr
ex {
import "runtime/internal/atomic"
Michael Anthony Knyszek [Mon, 18 Oct 2021 23:12:16 +0000 (23:12 +0000)]
runtime: retype mheap.reclaimIndex as atomic.Uint64
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
add mheap.reclaimIndex \
// reclaimIndex is the page index in allArenas of next page to \
// reclaim. Specifically, it refers to page (i % \
// pagesPerArena) of arena allArenas[i / pagesPerArena]. \
// \
// If this is >= 1<<63, the page reclaimer is done scanning \
// the page marks. \
reclaimIndex_ atomic.Uint64
ex {
import "runtime/internal/atomic"
Michael Anthony Knyszek [Mon, 18 Oct 2021 23:10:43 +0000 (23:10 +0000)]
runtime: retype mheap.pagesSweptBasis as atomic.Uint64
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
add mheap.pagesSweptBasis pagesSweptBasis_ atomic.Uint64 // pagesSwept to use as the origin of the sweep ratio
ex {
import "runtime/internal/atomic"
Michael Anthony Knyszek [Fri, 15 Oct 2021 19:22:10 +0000 (19:22 +0000)]
runtime: retype mheap.pagesInUse as atomic.Uint64
[git-generate]
cd src/runtime
mv export_test.go export.go
GOROOT=$(dirname $(dirname $PWD)) rf '
add mheap.pagesInUse \
// Proportional sweep \
// \
// These parameters represent a linear function from gcController.heapLive \
// to page sweep count. The proportional sweep system works to \
// stay in the black by keeping the current page sweep count \
// above this line at the current gcController.heapLive. \
// \
// The line has slope sweepPagesPerByte and passes through a \
// basis point at (sweepHeapLiveBasis, pagesSweptBasis). At \
// any given time, the system is at (gcController.heapLive, \
// pagesSwept) in this space. \
// \
// It is important that the line pass through a point we \
// control rather than simply starting at a 0,0 origin \
// because that lets us adjust sweep pacing at any time while \
// accounting for current progress. If we could only adjust \
// the slope, it would create a discontinuity in debt if any \
// progress has already been made. \
pagesInUse_ atomic.Uint64 // pages of spans in stats mSpanInUse
ex {
import "runtime/internal/atomic"
Robert Findley [Wed, 20 Oct 2021 18:54:13 +0000 (14:54 -0400)]
go/internal/gcimporter: avoid setting unnecessary lines in fakeFileSet
This is a clean port of CL 357291 from x/tools.
For #46586
Change-Id: Ib22087ae7fe8477d368acd230b263b83cdad4d36
Reviewed-on: https://go-review.googlesource.com/c/go/+/357429
Trust: Robert Findley <rfindley@google.com>
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