When inlining function calls, we rewrite the position information on
all of the nodes to keep track of the inlining context. This is
necessary so that at runtime, we can synthesize additional stack
frames so that the inlining is transparent to the user.
However, for function literals, we *don't* want to apply this
rewriting to the underlying function. Because within the function
literal (when it's not itself inlined), the inlining context (if any)
will have already be available at the caller PC instead.
Unified IR was already getting this right in the case of user-written
statements within the function literal, which is what the unit test
for #46234 tested. However, it was still using inline-adjusted
positions for the function declaration and its parameters, which
occasionally end up getting used for generated code (e.g., loading
captured values from the closure record).
I've manually verified that this fixes the hang in
https://go.dev/play/p/avQ0qgRzOgt, and spot-checked the
-d=pctab=pctoinline output for kube-apiserver and kubelet and they
seem better.
However, I'm still working on a more robust test for this (hence
"Updates" not "Fixes") and internal assertions to verify that we're
emitting correct inline trees. In particular, there are still other
cases (even in the non-unified frontend) where we're producing
corrupt (but at least acyclic) inline trees.
Updates #54625.
Change-Id: Iacfd2e1eb06ae8dc299c0679f377461d3d46c15a
Reviewed-on: https://go-review.googlesource.com/c/go/+/425395
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Elapsed returns the measured elapsed time of the benchmark,
but does not change the running state of the timer.
Fixes#43620.
Change-Id: Idd9f64c4632518eec759d2ffccbf0050d84fcc03
Reviewed-on: https://go-review.googlesource.com/c/go/+/420254
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: hopehook <hopehook@qq.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Given a composite literal type S, rather than always printing
(S literal) for a composite literals, print S{} if the literal
has no elements, and print S{…} as a short form (suitable for
error messages) if there are elements. This matches types2 and
also Go1.17 compiler behavior (except that the original compiler
would print ... rather than …). Using … rather than ... makes
it clearer that we don't have real Go syntax, and it's also more
compact.
For #54511.
Change-Id: I5991e8060232f16ecbf4a1fe4ae091598fc76b68
Reviewed-on: https://go-review.googlesource.com/c/go/+/425006
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
On LR architectures, morestack (and morestack_noctxt) are called
with a special calling convention, where the caller doesn't save
LR on stack but passes it as a register, which morestack will save
to g.sched.lr. The stack unwinder currently doesn't understand it,
and would fail to unwind from it. morestack already writes SP (as
it switches stack), but morestack_noctxt (which tailcalls
morestack) doesn't. If a profiling signal lands right in
morestack_noctxt, the unwinder will try to unwind the stack and
go off, and possibly crash.
Marking morestack_noctxt SPWRITE stops the unwinding.
Ideally we could teach the unwinder about the special calling
convention, or change the calling convention to be less special
(so the unwinder doesn't need to fetch a register from the signal
context). This is a stop-gap solution, to stop the unwinder from
crashing.
Fixes#54332.
Change-Id: I75295f2e27ddcf05f1ea0b541aedcb9000ae7576
Reviewed-on: https://go-review.googlesource.com/c/go/+/425396
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Some tests in misc/cgo/testsanitizers had been disabled on ppc64le
until recently, due to an intermittent error in the tsan tests,
with the goal of trying to understand the failure.
After further investigation, I found that the code for tsan within
gcc does not work consistently when ASLR is enabled on ppc64le. A
fix for that problem was integrated in gcc 9.
This adds a check to testsanitizers to determine the gcc compiler
version on ppc64le and skip the test if the version is too old.
A similar check is needed for asan too.
Updates #54645
Change-Id: I70717d1aa9e967cf1e871566e72b3862b91fea3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/425355
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Archana Ravindar <aravind5@in.ibm.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Also:
- fine-tune the implementation for some of the new builtin functions
- make sure the go/types code is an exact as possible copy of the
types2 code
- fix the description and examples for errorcodes.go
Follow-up on CL 423754.
For #53003.
Change-Id: I5c70b74e90c724cf6c842cedc6f8ace26fde372b
Reviewed-on: https://go-review.googlesource.com/c/go/+/425454
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
For "type T interface{ M() }", go/types users expect T's underlying
interface type to specify T as the receiver parameter type (#49906).
The unified importer handles this by cloning the interface to rewrite
the receiver parameters before calling SetUnderlying.
I missed in CL 425360 that these interfaces would need to have
Complete called too.
Manually tested to confirm that this actually fixes "go test -race
golang.org/x/tools/go/analysis/internal/checker" now (when both CLs
are ported to the x/tools importer).
Updates #54653.
Change-Id: I51e6db925db56947cd39dbe880230f14734ca01c
Reviewed-on: https://go-review.googlesource.com/c/go/+/425365
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
To support concurrent use of the go/types API, importers need to call
Interface.Complete on constructed interfaces before returning.
There's an issue that the interfaces may contain embedded defined
types, whose underlying type isn't known yet. This issue will
eventually go away once CL 424876 lands, but that CL needs to wait for
CL 424854 to re-land, which needs to wait for CL 421879 to land...
In the mean time, this CL implements the same solution used by the
indexed importer: maintaining a list of constructed interfaces, and
calling Interface.Complete on them after the SetUnderlying loop and
just before returning the imported package.
Updates #54653.
Change-Id: I0f42c915a4b7d28c628bbab7ac2eab2415c7858f
Reviewed-on: https://go-review.googlesource.com/c/go/+/425360
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Add content generated by 'relnote -html'. This covers all of known
TODOs available by 2022-08-24 such that relnote produces no output
when -exclude-from=doc/go1.20.html flag is used.
For #54202.
Change-Id: Icd9be5364bc73c3de56d5d3039e6f313908af38e
Reviewed-on: https://go-review.googlesource.com/c/go/+/425354
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
This is a follow up of CL 425101 on RISCV64.
According to RISCV Volume 1, Unprivileged Spec v. 20191213 Chapter 7.1:
If both the high and low bits of the same product are required, then the
recommended code sequence is: MULH[[S]U] rdh, rs1, rs2; MUL rdl, rs1, rs2
(source register specifiers must be in same order and rdh cannot be the
same as rs1 or rs2). Microarchitectures can then fuse these into a single
multiply operation instead of performing two separate multiplies.
So we should not split Muluhilo to separate instructions.
Updates #54607
Change-Id: If47461f3aaaf00e27cd583a9990e144fb8bcdb17
Reviewed-on: https://go-review.googlesource.com/c/go/+/425203
Auto-Submit: Keith Randall <khr@golang.org>
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Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
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Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
This initial release notes template is based on previous releases.
CL 425354 adds initial content generated by 'relnote -html'.
For #54202.
Change-Id: I36e15723edc9610d61986ba226ee84c2b30a33af
Reviewed-on: https://go-review.googlesource.com/c/go/+/425334
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
These tests invoke the system C compiler and linker.
Skipping them saves a little over half a second of time in short mode.
Updates #54423.
Change-Id: I3e8aa7b53c0c91f7d1e001ec2cd5f7b4954de52d
Reviewed-on: https://go-review.googlesource.com/c/go/+/425206
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
Ever since 'go build' was added (in CL 5483069), it has used an atexit
handler to clean up working directories. At some point (prior to CL
95900044), Init was called multiple times per builder, registering
potentially many atexit handlers that execute asynchronously and make
debugging more difficult.
The use of an AtExit handler also makes the Builder (and anything that
uses it) prone to races: the base.AtExit API is not designed for
concurrent use, but cmd/go is becoming increasingly concurrent over
time. The AtExit handler also makes the Builder inappropriate to use
within a unit-test, since the handlers do not run during the test
function and accumulate over time.
This change makes NewBuilder safe for concurrent use by registering
the AtExit handler only once (during BuildInit, which was already not
safe for concurrent use), and using a sync.Map to store the set of
builders that need cleanup in case of an unclean exit. In addition, it
causes the test variant of cmd/go to fail if any Builder instance
leaks from a clean exit, helping to ensure that functions that create
Builders do not leak them indefinitely, especially in tests.
Updates #54423.
Change-Id: Ia227b15b8fa53c33177c71271d756ac0858feebe
Reviewed-on: https://go-review.googlesource.com/c/go/+/425254
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Bryan Mills <bcmills@google.com>
Ever since 'go build' was added (in CL 5483069), it has used an atexit
handler to clean up working directories.
CL 154109 introduced 'cc' command to the script test framework that
called Init on a builder once per invocation. Unfortunately, since
base.AtExit is unsynchronized, the Init added there caused any script
that invokes that command to be unsafe for concurrent use.
This change fixes the race by having the 'cc' command pass in its
working directory instead of allowing the Builder to allocate one.
Following modern Go best practices, it also replaces the in-place Init
method (which is prone to typestate and aliasing bugs) with a
NewBuilder constructor function.
Fixes#54423.
Change-Id: I8fc2127a7d877bb39a1174e398736bb51d03d4d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/425205
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Bryan Mills <bcmills@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
This CL changes the inliner to process transitive inlining iteratively
after the AST has actually been edited, rather than recursively and
immediately. This is important for handling indirect function calls
correctly, because ir.reassigned walks the function body looking for
reassignments; whereas previously the inlined reassignments might not
have been actually added to the AST yet.
Fixes#54632.
Change-Id: I0dd69813c8a70b965174e0072335bc00afedf286
Reviewed-on: https://go-review.googlesource.com/c/go/+/425257
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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Reviewed-by: David Chase <drchase@google.com>
If a struct or array is comparable, then we can leverage rtype.equal,
which is almost always faster than what Go reflection can achieve.
As a secondary optimization, pre-compute Value.Len and Value.NumField
outside of the loop conditional.
Performance:
name old time/op new time/op delta
IsZero/ArrayComparable 136ns ± 4% 16ns ± 1% -88.28% (p=0.008 n=5+5)
IsZero/ArrayIncomparable 197ns ±10% 123ns ± 1% -37.74% (p=0.008 n=5+5)
IsZero/StructComparable 26.4ns ± 0% 9.6ns ± 1% -63.68% (p=0.016 n=4+5)
IsZero/StructIncomparable 43.5ns ± 1% 27.8ns ± 1% -36.21% (p=0.008 n=5+5)
The incomparable types gain a performance boost since
they are generally constructed from nested comparable types.
Change-Id: If2c1929f8bb1b5b19306ef0c69f3c95a27d4b60d
Reviewed-on: https://go-review.googlesource.com/c/go/+/411478
Reviewed-by: Dan Kortschak <dan@kortschak.io>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Change-Id: I5987eed00ee825421abe62699a06e9b66499f35f
Reviewed-on: https://go-review.googlesource.com/c/go/+/425016
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: David Chase <drchase@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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So next CLs can revert changes to "internal/singleflight" in CL #82795,
then replace it with "golang.org/x/sync/singleflight" instead.
For #31697
Change-Id: I873ce30d7e051539aa6dc5d4f21e558869a6d132
Reviewed-on: https://go-review.googlesource.com/c/go/+/423654
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Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Change-Id: Ied16c3be47c863a94d46bd568191057ded4b7d0a
Reviewed-on: https://go-review.googlesource.com/c/go/+/416734
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Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: xiaodong liu <teaofmoli@gmail.com>
This causes a problem in the test sometimes. With a mapping like:
00400000-00411000 r--p 00000000 fe:01 4459044 /tmp/go-build1710804385/b001/pprof.test
00411000-00645000 r-xp 00011000 fe:01 4459044 /tmp/go-build1710804385/b001/pprof.test
The removed code would make the first mapping 0x400000-0x645000. Tests
then grab the first few addresses to use as PCs, thinking they are in
an executable range. But those addresses are really not in an
executable range, causing the tests to fail.
Change-Id: I5a69d0259d1fd70ff9745df1cbad4d54c5898e7b
Reviewed-on: https://go-review.googlesource.com/c/go/+/424295
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Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
JoinPath would fail to remove relative elements from the start of
the path when the first path element is "".
In addition, JoinPath would return the original path unmodified
when provided with no elements to join, violating the documented
behavior of always cleaning the resulting path.
Correct both these cases.
JoinPath("http://go.dev", "../go")
// before: http://go.dev/../go
// after: http://go.dev/go
JoinPath("http://go.dev/../go")
// before: http://go.dev/../go
// after: http://go.dev/goFixes#54385.
Change-Id: I6d22cd160d097c50703dd96e4f453c6c118fd5d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/423514
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
Detect rotate instructions while still in architecture-independent form.
It's easier to do here, and we don't need to repeat it in each
architecture file.
Change-Id: I9396954b3f3b3bfb96c160d064a02002309935bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/421195
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Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Joedian Reid <joedian@golang.org>
Reviewed-by: Ruinan Sun <Ruinan.Sun@arm.com>
Run-TryBot: Keith Randall <khr@golang.org>
From the append docs in the builtin package:
As a special case, it is legal to append a string to a byte slice, like this:
slice = append([]byte("hello "), "world"...)
Change-Id: Ib14039a7476873b12a3aefccd8863e8d628b9249
Reviewed-on: https://go-review.googlesource.com/c/go/+/425102
Reviewed-by: hopehook <hopehook@qq.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: David Chase <drchase@google.com>
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Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
No debug/plan9obj test case because the problem can only happen for
invalid data. Let the fuzzer find cases like this.
For #47653Fixes#54585
Change-Id: I8d3e15725b9bc09dd0e6f2750769987021f5e982
Reviewed-on: https://go-review.googlesource.com/c/go/+/425115
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
If narch is very large we would allocate a lot of memory for seenArches.
In practice we aren't going to see many different architectures so
don't bother to specify a size for the seenArches map.
No debug/macho test case because the problem can only happen for
invalid data. Let the fuzzer find cases like this.
For #47653
For #52523
Change-Id: I5a3b0e3aa6172ddffd6f44d9ae513c39a00d8764
Reviewed-on: https://go-review.googlesource.com/c/go/+/425114
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Reviewed-by: David Chase <drchase@google.com>
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Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
When one has a []byte on hand, but desires to call the Parse functions,
the conversion from []byte to string would allocate.
var b []byte = ...
v, err := strconv.ParseXXX(string(b), ...)
This changes it such that the input string never escapes from
any of the Parse functions. Together with the compiler optimization
where the compiler stack allocates any string smaller than 32B
this makes most valid inputs for strconv.ParseXXX(string(b), ...)
not require an allocation for the input string.
For example, the longest int64 or uint64 encoded in decimal is 20B.
Also, the longest decimal formatting of a float64 in appendix B
of RFC 8785 is 25B.
Previously, this was not possible since the input leaked to the error,
which causes the prover to give up and instead heap copy the []byte.
We fix this by copying the input string in the error case.
The advantage of this change is that you can now call strconv.ParseXXX
with a []byte without allocations (most times) in the non-error case.
The detriment is that the error-case now has an extra allocation.
We should optimize for the non-error path, rather than the error path.
The effects of this change is transitively seen through packages
that must use strconv.ParseXXX on a []byte such as "encoding/json":
name old time/op new time/op delta
UnmarshalFloat64 186ns 157ns -15.89% (p=0.000 n=10+10)
name old alloc/op new alloc/op delta
UnmarshalFloat64 148B 144B -2.70% (p=0.000 n=10+10)
name old allocs/op new allocs/op delta
UnmarshalFloat64 2.00 1.00 -50.00% (p=0.000 n=10+10)
In order for "encoding/json" to benefit, there needs to be a
small change made to how "encoding/json" calls strconv.ParseXXX.
That will be a future change.
Credit goes to Jeff Wendling for a similar patch.
Fixes#42429
Change-Id: I512d6927f965f82e95bd7ec14a28a587f23b7203
Reviewed-on: https://go-review.googlesource.com/c/go/+/345488
Reviewed-by: Martin Möhrmann <martin@golang.org>
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Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Use explicit name pdNil for nil semaphore of a pollDesc to make it self-explanatory like pdReady and pdWait.
Change-Id: Ibfb246e14419d366edadbccac4d3717f0c135cb0
Reviewed-on: https://go-review.googlesource.com/c/go/+/424923
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This is both simpler and more performant.
Change-Id: I66ef8e49c059a722932392ee3ecfb951d9b8e121
Reviewed-on: https://go-review.googlesource.com/c/go/+/412339
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Some code paths in the runtime (cgo, heapdump) request heap bits
without first checking that the span is !noscan. Instead of trying
to find and work around all those cases, just set the pointer bits
of noscan spans correctly. It's somewhat safer than ensuring we
caught all the possible cases.
Fixes#54557Fixes#54558
Change-Id: Ibd476e6cdea77c962e4d15aad26f29df66fd94e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/425194
Reviewed-by: Michael Knyszek <mknyszek@google.com>
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Normally, when moving Go values of type T from one location to another,
we don't need to worry about partial overlaps. The two Ts must either be
in disjoint (nonoverlapping) memory or in exactly the same location.
There are 2 cases where this isn't true:
1) Using unsafe you can arrange partial overlaps.
2) Since Go 1.17, you can use a cast from a slice to a ptr-to-array.
https://go.dev/ref/spec#Conversions_from_slice_to_array_pointer
This feature can be used to construct partial overlaps of array types.
var a [3]int
p := (*[2]int)(a[:])
q := (*[2]int)(a[1:])
*p = *q
We don't care about solving 1. Or at least, we haven't historically
and no one has complained.
For 2, we need to ensure that if there might be partial overlap,
then we can't use OpMove; we must use memmove instead.
(memmove handles partial overlap by copying in the correct
direction. OpMove does not.)
Note that we have to be careful here not to introduce a call when
we're marshaling arguments to a call or unmarshaling results from a call.
Fixes#54467
Change-Id: I1ca6aba8041576849c1d85f1fa33ae61b80a373d
Reviewed-on: https://go-review.googlesource.com/c/go/+/425076
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
This reverts CL 424854.
Reason for revert: broke misc/cgo/stdio.TestTestRun on several builders.
Will re-land after CL 421879 is submitted.
Change-Id: I2548c70d33d7c178cc71c1d491cd81c22660348f
Reviewed-on: https://go-review.googlesource.com/c/go/+/425214
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
R0 needs to be cleared at startup as it may not always be cleared
by the kernel on newer kernels.
Fixes#54547
Change-Id: Id7055699aaa8d8b193b7e3e784f075ce29ac3f1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/424927
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
None of cgo, "go test", nor srcimporter make use of go/ast's object
resolution via go/ast.Object. As such, we can skip that work during
parse time, which should save some CPU time.
We don't have any benchmark numbers, as none of the three packages have
any usable benchmarks, but we measured gofmt to be about 5% faster
thanks to this tweak in https://go.dev/cl/401454.
These three packages are quite different to gofmt, but one can expect
similar speed-ups in the 1-5% range.
Two notable exceptions, which do make use of go/ast.Object, are cmd/fix
and cmd/doc - we do not modify those here.
See #46485.
Change-Id: Ie3e65600d4790641c4e4d6f1c379be477fa02cee
Reviewed-on: https://go-review.googlesource.com/c/go/+/401455
Run-TryBot: Bryan Mills <bcmills@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Flush can not check for unclosed elements, as more data might be encoded
after Flush is called. Close implicitly calls Flush and also checks that
all opened elements are closed as well.
Fixes#53346
Change-Id: I889b9f5ae54e5dfabb9e6948d96c5ed7bc1110f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/424777
TryBot-Result: Gopher Robot <gobot@golang.org>
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: David Chase <drchase@google.com>
These two functions together duplicated much of the functionality of
modload.Lookup. Use that instead in modcmd.vendorPkg, and reduce the
modload surface area.
Updates #42504
Updates #40775
For #26904
Change-Id: Ib8aaac495d090178dd56971aef9e5aa44ffa818b
Reviewed-on: https://go-review.googlesource.com/c/go/+/332571
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Bryan Mills <bcmills@google.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
In CL 424734, I implemented pointer shaping for unified IR. Evidently
though, we didn't have any test cases that check that uses of
pointer-shaped expressions were handled correctly.
In the reported test case, the struct field "children items[*node[T]]"
gets shaped to "children items[go.shape.*uint8]" (underlying type
"[]go.shape.*uint8"); and so the expression "n.children[i]" has type
"go.shape.*uint8" and the ".items" field selection expression fails.
The fix implemented in this CL is that any expression of derived type
now gets an explicit "reshape" operation applied to it, to ensure it
has the appropriate type for its context. E.g., the "n.children[i]"
OINDEX expression above gets "reshaped" from "go.shape.*uint8" to
"*node[go.shape.int]", allowing the field selection to succeed.
This CL also adds a "-d=reshape" compiler debugging flag, because I
anticipate debugging reshaping operations will be something to come up
again in the future.
Fixes#54535.
Change-Id: Id847bd8f51300d2491d679505ee4d2e974ca972a
Reviewed-on: https://go-review.googlesource.com/c/go/+/424936
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: hopehook <hopehook@qq.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
