When writing an object file, most symbols are indexed in
NumberSyms. Currently, pcdata symbols are indexed late and
separately. This is not really necessary, as pcdata symbols
already exist at the time of NumberSyms. Just do it there.
As pcdata symbols are laid out in the pclntab in a special way at
link time, distinguish them from other symbols in the content
hash. (In the old code this was partly achieved by indexing them
late.)
Change-Id: Ie9e721382b0af2cfb39350d031e2e66d79095a3c
Reviewed-on: https://go-review.googlesource.com/c/go/+/352611
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As pointed out in #47916, the IsConstraint method becomes ambiguously
named if ever we allow interfaces with structural restrictions outside
of constraint position.
Add instead an IsMethodSet method, which has the opposite sense and
avoids this ambiguity. In a subsequent CL the IsConstraint method will
be removed, once x/tools has been updated to use the IsMethodSet API.
Updates #47916
Change-Id: I82ad16b111464b0cd2f354b8ecdd4b3f14796cd9
Reviewed-on: https://go-review.googlesource.com/c/go/+/352616
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In #47916, consensus has emerged that adding a new constructor is
preferable to using setters for type parameters. This is more consistent
with the rest of the type API, which is immutable except in cases where
mutation is necessary to break cycles (such as Named.SetUnderlying).
This CL adds a new constructor NewSignatureType that accepts type
parameters and receiver type parameters, deprecating the existing
NewSignature constructor. SetTypeParams and SetRecvTypeParams are not
yet removed: this will be done in a follow-up CL once x/tools no longer
has a dependency on the old APIs.
Updates #47916
Change-Id: I9d04dcfd304344d2aa08e527b371c3faa9d738e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/352615
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The goal of this change is to improve the documentation
and make it easier to keep Link.NumberSyms and writer.contentHash aligned.
No functional changes.
A subsequent change will add conditions to contentHashSection.
Change-Id: I0a274f6974459d34d5a8553081f33ea4cd87f248
Reviewed-on: https://go-review.googlesource.com/c/go/+/352669
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As of CL 247399 we use separate symbols for PCDATA. There is no
more need for writing PCDATA directly into the object file as a
separate block.
Change-Id: I942d1a372540415e0cc07fb2a01f79718a264142
Reviewed-on: https://go-review.googlesource.com/c/go/+/352610
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Fixes#48620
Change-Id: I37a5909ad27dc4a170929cb2e2ed1045cf524d59
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We were putting type descriptor funcdata,
such as type..eq.[2]interface {}.arginfo1
in type.* or typerel.* instead of go.func.*.
Fix that.
Change-Id: I779e6be3dd91c8029f2c3dc0e10a7d597c16678f
Reviewed-on: https://go-review.googlesource.com/c/go/+/352071
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A subsequent change will duplicate most of case ver116.
Make it easier to read.
Change-Id: I3a93181c7f094b12715b8a618e9efef7a1438a27
Reviewed-on: https://go-review.googlesource.com/c/go/+/351909
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The test is flaky on Android. VDSO may not be enabled so it may
not have the original problem anyway.
Change-Id: I73c2902c682a44d893e0d4e34f006c2377ef8816
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As discussed in #47658, Value already has CanAddr and CanInterface to
test if a call to Addr or Inteface, respectively, does not result in a
panic.
Therefore we add CanInt, CanUint, CanFloat and CanComplex to ease the
test for a possible panic in calling, respectively, Int, Uint, Float and
Complex.
Fixes#47658
Change-Id: I58b77d77e6eec9f34234e985f631eab72b5b935e
Reviewed-on: https://go-review.googlesource.com/c/go/+/352131
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Fix some comments.
Adjust capitalization for initialisms.
Use a println directly instead of emulating it.
Change-Id: I0d8fa0eb39547e2db8113fd0358136285b86f16a
Reviewed-on: https://go-review.googlesource.com/c/go/+/351462
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This will be required when we change from storing entry PCs in _func
to entry PC offsets, which are relative to the containing module.
Notably, almost all uses of the entry method were already called
on a funcInfo. Only Func.Entry incurs the additional module
lookup cost.
This makes Entry considerably slower, but it is probably
still fast enough in absolute terms that it is OK.
name old time/op new time/op delta
Func/Name-8 8.86ns ± 0% 8.33ns ± 2% -5.92% (p=0.000 n=12+13)
Func/Entry-8 0.64ns ± 0% 2.62ns ±36% +310.07% (p=0.000 n=14+15)
Func/FileLine-8 24.5ns ± 0% 25.0ns ± 4% +2.21% (p=0.015 n=14+13)
Change-Id: Ia2d5de5f2f83fab334f1875452b9e8e87651d340
Reviewed-on: https://go-review.googlesource.com/c/go/+/351461
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A subsequent change will alter the semantics of _func.entry.
To make that change obvious and clear, change _func.entry to a method,
and rename the field to _func.entryPC.
Change-Id: I05d66b54d06c5956d4537b0729ddf4290c3e2635
Reviewed-on: https://go-review.googlesource.com/c/go/+/351460
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_func and funcinl are type-punned.
We distinguish them at runtime by inspecting the first word.
Prior to this change, we used 0 as the sentinel value
that means that a Func is a funcinl.
That worked because _func's first word is the functions' entry PC,
and 0 is not a valid PC. I plan to make *_func's entry PC relative
to the containing module. As a result, 0 will be a valid value,
for the first function in the module.
Switch to ^0 as the new sentinel value, which is neither a valid
entry PC nor a valid PC offset.
Change-Id: I4c718523a083ed6edd57767c3548640681993522
Reviewed-on: https://go-review.googlesource.com/c/go/+/351459
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runtime.Func.{Name,FileLine} need to be able to
go from a *_func to a funcInfo. The missing bit of
information is what module contains that *_func.
The existing implementation looked up the module
using the *_func's entry PC. A subsequent change will
store *_func's entry PC relative to the containing module.
Change the module lookup to instead for the module
whose pclntable contains the *_func,
cutting all dependencies on the contents of the *_func.
Change-Id: I2dbbfec043ebc2e9a6ef19bbdec623ac84353b10
Reviewed-on: https://go-review.googlesource.com/c/go/+/351458
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Instead of growing 2x for < 1024 elements and 1.25x for >= 1024 elements,
use a somewhat smoother formula for the growth factor. Start reducing
the growth factor after 256 elements, but slowly.
starting cap growth factor
256 2.0
512 1.63
1024 1.44
2048 1.35
4096 1.30
(Note that the real growth factor, both before and now, is somewhat
larger because we round up to the next size class.)
This CL also makes the growth monotonic (larger initial capacities
make larger final capacities, which was not true before). See discussion
at https://groups.google.com/g/golang-nuts/c/UaVlMQ8Nz3o
256 was chosen as the threshold to roughly match the total number of
reallocations when appending to eventually make a very large
slice. (We allocate smaller when appending to capacities [256,1024]
and larger with capacities [1024,...]).
Change-Id: I876df09fdc9ae911bb94e41cb62675229cb10512
Reviewed-on: https://go-review.googlesource.com/c/go/+/347917
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We currently make dictionaries contain a relocation pointing to
methods that generic code might use, so that those methods are not
deadcode eliminated. However, with inlining we can end up not using
the dictionary, making the reference from the dictionary to the method
no longer keep the method alive.
Fix this by keeping the dictionary alive at generic interface call sites.
It's a bit of overkill, as we only need to keep the dictionary statically
alive. We don't actually need it dynamically alive, which is what KeepAlive
does. But it works. It ends up generating a LEAQ + stack spill that aren't
necessary, but that's pretty low overhead.
To make this work, I needed to stop generating methods on shape types.
We should do this anyway, as we shouldn't ever need them. But currently
we do use them! issue44688.go has a test that only works because it calls
a method on a shape type. I've disabled that test for now, will work on it
in a subsequent CL.
Fixes#48047
Change-Id: I78968868d6486c1745f51b8b43be0898931432a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/349169
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In a previous change, I was too aggressive in substInstType() in not
generating methods for shape types during import. We do actually want to
generate the method nodes - we just don't want to generate method bodies
(which we would never use). We may need the method nodes for checking
types later in the compile (especially with inlining).
So, we do generate method nodes for shape types during import. In
order to avoid the name collision we previously had, we now add
".nofunc." to the method nodes for shape types (during import and in the
type substituter). We do that by passing in a 'isMethodNode' arg to
MakeInstSym. We keep the normal name (without ".nofunc") for any other
method nodes, and for the instantiated functions that help with
implementing the methods of fully-instantiated types. The ".nofunc"
names will never appear in the executable, since we don't generate any
method bodies for the method nodes of shape types.
Change-Id: I3e57e328691214140ca5f48d32011552d2a0d45d
Reviewed-on: https://go-review.googlesource.com/c/go/+/352470
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The dictionary argument is implicit; the user doesn't need to see it.
Update #48578
Change-Id: I367ba4b6622119d3e01aaded90463d16823915a7
Reviewed-on: https://go-review.googlesource.com/c/go/+/352119
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They tend to be things like ".shape.int" which are noisy, if not
otherwise confusing.
It would be nice to somehow print the real instantiations here, but that
requires keeping track of the dictionary argument so the instantiating
types could be found. One day, maybe, but not today.
Fixes#48578
Change-Id: I0968d24e110b6d47c9468c45372a6979575a8d29
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The sigprofNonGo and sigprofNonGoPC functions are only used on unix-like
platforms. In preparation for unix-specific changes to sigprofNonGo,
move it (plus its close relative) to a unix-specific file.
Updates #35057
Change-Id: I9c814127c58612ea9a9fbd28a992b04ace5c604d
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Using setitimer on Linux to request SIGPROF signal deliveries in
proportion to the process's on-CPU time results in under-reporting when
the program uses several goroutines in parallel. Linux calculates the
process's total CPU spend on a regular basis (often every 4ms); if the
process has spent enough CPU time since the last calculation to warrant
more than one SIGPROF (usually 10ms for the default sample rate of 100
Hz), the kernel is often able to deliver only one of them. With these
common settings, that results in Go CPU profiles being attenuated for
programs that use more than 2.5 goroutines in parallel.
To avoid in effect overflowing the kernel's process-wide CPU counter,
and relying on Linux's typical behavior of having the active thread
handle the resulting process-targeted signal, use timer_create to
request a timer for each OS thread that the Go runtime manages. Have
each timer track the CPU time of a single thread, with the resulting
SIGPROF going directly to that thread.
To continue tracking CPU time spent on threads that don't interact with
the Go runtime (such as those created and used in cgo), keep using
setitimer in addition to the new mechanism. When a SIGPROF signal
arrives, check whether it's due to setitimer or timer_create and filter
as appropriate: If the thread is known to Go (has an M) and has a
timer_create timer, ignore SIGPROF signals from setitimer. If the thread
is not known to Go (does not have an M), ignore SIGPROF signals that are
not from setitimer.
Counteract the new bias that per-thread profiling adds against
short-lived threads (or those that are only active on occasion for a
short time, such as garbage collection workers on mostly-idle systems)
by configuring the timers' initial trigger to be from a uniform random
distribution between "immediate trigger" and the full requested sample
period.
Updates #35057
Change-Id: Iab753c4e5101bdc09ef9132eec84a75478e05579
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This adds ABIInternal to the race function declarations.
Change-Id: I99f8a310972ff09b4d56eedbcc6e9609bab0f224
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Change-Id: Ie90d8dd3f644a96cda706c6a5286e99042e070bb
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Updates golang/go#37595
Change-Id: I7568e7416d5504e9dc67061c79f66e3a0d597dee
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Change-Id: I9921ba5c29ada6ff06d147f6d9b46a29101c449c
Reviewed-on: https://go-review.googlesource.com/c/go/+/350694
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Change-Id: Ic0a97fd7bb89865448e436e5c092415a29d8badf
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Cribbed and modified from arm64, verify each transformation
rewrites a too-far conditional branch as expected.
Change-Id: I87d35085158ed7d7478aa9725b273401fcd0bd01
Reviewed-on: https://go-review.googlesource.com/c/go/+/347049
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This adds the changes for the register ABI in the runtime
functions for ppc64x:
- Add spill functions used by runtime
- Add ABIInternal to functions
Some changes were needed to the stubs files
due to vet issues when compiling for linux/ppc64.
Change-Id: I010ddbc774ed4f22e1f9d77833bd55b919d95c99
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This should have been part of https://golang.org/cl/340049 but I
overlooked it. That commit added fast path code when the destination
image was *not* an *image.RGBA. This commit edits func drawRGBA.
name old time/op new time/op delta
RGBA1-4 5.11ms ± 1% 1.12ms ± 1% -78.01% (p=0.008 n=5+5)
RGBA2-4 8.69ms ± 1% 2.98ms ± 1% -65.77% (p=0.008 n=5+5)
Updates #44808.
Updates #46395.
Change-Id: I899d46d985634fc81ea47ff4f0d436630e8a961c
Reviewed-on: https://go-review.googlesource.com/c/go/+/351852
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In CL 349613,we have supported types.IdentityStrict() that does strict
type comparison.
Therefore, OCONVNOP becomes a possible case in call.X.Op().
Fixes#48604
Change-Id: Ibab27ffcf09656e3380314662f05f38294c1c6ed
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For #48617
Change-Id: I6c00b7912c441ac323a0adede63b7d4a9ae6f92d
Reviewed-on: https://go-review.googlesource.com/c/go/+/351858
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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In CL 349614. we removed the early transformation code that
was needed to create the implicit CONVIFACE nodes.
Because the transformCall function is not called when translating OFUNCINST.
So we add in needed CONVIFACE nodes via typecheckaste().
Fixes#48598
Change-Id: If9dc7040cdc38ef2e52fdbb08c840095651426f2
Reviewed-on: https://go-review.googlesource.com/c/go/+/351856
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Deal correctly with a blank local variable with type param type. This is
a special case, because a blank local variable is not in the fn.Dcl
list. In this case, we must explicitly create a new blank node with the
correct substituted type, so we have correct types if the blank local
variable has an initializing assignment.
Fixes#48602
Change-Id: I903ea44b29934e180404e32800773b7309bf297b
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Based on comments in CL 348469.
Note that with this change, F.Fuzz no longer calls
runtime.Goexit. This simplifies our logic and makes F.Fuzz more
predictable.
Change-Id: I6c3c65b0e8e8f261621cbe2f17375e8164ef60a0
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gofmt is pretty heavily CPU-bound, since parsing and formatting 1MiB
of Go code takes much longer than reading that amount of bytes from
disk. However, parsing and manipulating a large Go source file is very
difficult to parallelize, so we continue to process each file in its
own goroutine.
A Go module may contain a large number of Go source files, so we need
to bound the amount of work in flight. However, because the
distribution of sizes for Go source files varies widely — from tiny
doc.go files containing a single package comment all the way up to
massive API wrappers generated by automated tools — the amount of
time, work, and memory overhead needed to process each file also
varies. To account for this variability, we limit the in-flight work
by bytes of input rather than by number of files. That allows us to
make progress on many small files while we wait for work on a handful
of large files to complete.
The gofmt tool has a well-defined output format on stdout, which was
previously deterministic. We keep it deterministic by printing the
results of each file in order, using a lazily-synchronized io.Writer
(loosly inspired by Haskell's IO monad). After a file has been
formatted in memory, we keep it in memory (again, limited by the
corresponding number of input bytes) until the output for all previous
files has been flushed. This adds a bit of latency compared to
emitting the output in nondeterministic order, but a little extra
latency seems worth the cost to preserve output stability.
This change is based on Daniel Martí's work in CL 284139, but using a
weighted semaphore and ephemeral goroutines instead of a worker pool
and batches. Benchmark results are similar, and I find the concurrency
in this approach a bit easier to reason about.
In the batching-based approach, the batch size allows us to "look
ahead" to find large files and start processing them early. To keep
the CPUs saturated and prevent stragglers, we would need to tune the
batch size to be about the same as the largest input files. If the
batch size is set too high, a large batch of small files could turn
into a straggler, but if the batch size is set too low, the largest
files in the data set won't be started early enough and we'll end up
with a large-file straggler.
One possible alternative would be to sort by file size instead of
batching: identify all of the files to be processed, sort from largest
to smallest, and then process the largest files first so that the
"tail" of processing covers the smallest files. However, that approach
would still fail to saturate available CPU when disk latency is high,
would require buffering an arbitrary amount of metadata in order to
sort by size, and (perhaps most importantly!) would not allow the
`gofmt` binary to preserve the same (deterministic) output order that
it has today.
In contrast, with a semaphore we can produce the same deterministic
output as ever using only one tuning parameter: the memory footprint,
expressed as a rough lower bound on the amount of RAM available per
thread. While we're below the memory limit, we can run arbitrarily
many disk operations arbitrarily far ahead, and process the results of
those operations whenever they become avaliable. Then it's up to the
kernel (not us) to schedule the disk operations for throughput and
latency, and it's up to the runtime (not us) to schedule the
goroutines so that they complete quickly.
In practice, even a modest assumption of a few megabytes per thread
seems to provide a nice speedup, and it should scale reasonably even
to machines with vastly different ratios of CPU to disk. (In practice,
I expect that most 'gofmt' invocations will work with files on at most
one physical disk, so the CPU:disk ratio should vary more-or-less
directly with the thread count, whereas the CPU:memory ratio is
more-or-less independent of thread count.)
name \ time/op baseline.txt 284139.txt simplified.txt
GofmtGorootCmd 11.9s ± 2% 2.7s ± 3% 2.8s ± 5%
name \ user-time/op baseline.txt 284139.txt simplified.txt
GofmtGorootCmd 13.5s ± 2% 14.4s ± 1% 14.7s ± 1%
name \ sys-time/op baseline.txt 284139.txt simplified.txt
GofmtGorootCmd 465ms ± 8% 229ms ±28% 232ms ±31%
name \ peak-RSS-bytes baseline.txt 284139.txt simplified.txt
GofmtGorootCmd 77.7MB ± 4% 162.2MB ±10% 192.9MB ±15%
For #43566
Change-Id: I4ba251eb4d188a3bd1901039086be57f0b341910
Reviewed-on: https://go-review.googlesource.com/c/go/+/317975
Trust: Bryan C. Mills <bcmills@google.com>
Trust: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
'go mod why -m' works by listing modules matching command line
arguments, then loading "all" packages and finding which of the listed
modules provide packages imported by the main module.
If go.mod is inconsistent (that is, a requirement has a lower version
than MVS would select when the module graph is loaded) and pruned
(that is, the module graph is only loaded when necessary), then
modload.ListModules may return modules with different versions than
would be selected in modload.LoadPackages.
'go mod why -m' was too strict about this, mapping module paths and
versions to packages. With this fix, it maps module paths without
versions to packages.
Fixes#48613
Change-Id: I836c46289bb647d6c46ec65e7589531da532d5e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/352115
Trust: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
The delayTransform only checks whether ir.CurFunc is generic function or
not. but when compiling a non-generic closure inside a generic function,
we also want to delay the transformation, which delayTransform fails to
detect, since when ir.CurFunc is the closure, not the top level function.
Instead, we must rely on irgen.topFuncIsGeneric field to decide whether
to delay the transformation, the same logic with what is being done for
not adding closure inside a generic function to g.target.Decls list.
Fixes#48609
Change-Id: I5bf5592027d112fe8b19c92eb906add424c46507
Reviewed-on: https://go-review.googlesource.com/c/go/+/351855
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: Dan Scales <danscales@google.com>
So next CL will make delayTransform to become irgen's method, because
the delay transform logic also depends on irgen.topFuncIsGeneric field.
For #48609
Change-Id: I660ed19856bd06c3b6f4279a9184db96175dea2d
Reviewed-on: https://go-review.googlesource.com/c/go/+/351854
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: Dan Scales <danscales@google.com>
In markType() in crawler.go, mark the type of a unexported field if it
is a fully-instantiated type, since we create and instantiate the
methods of any fully-instantiated type that we see during import. As
before, we still do not mark the type of an unexported field if that
type is not generic. Fixes#48454 and most recent issue described in
48337. The included test is similar to the case in 48454.
Fixes#48454Fixes#48337
Change-Id: I77a2a62b9e2647876facfa6f004201e8f699c905
Reviewed-on: https://go-review.googlesource.com/c/go/+/351315
Trust: Dan Scales <danscales@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
When I separate out the dictionary transformations to dictPass, I missed
duplicating a conditional that deals with OMETHVALUE nodes that are
actually called. We create the OMETHVALUE when transforming bounds
function reference (before we know whether that reference will be
called), and we need to call transformDot() again to convert the
OMETHVALUE to ODOTMETH if the reference is actually called (the usual
case). Without this change, we leave the OMETHVALUE in, and extra *-fm
are created and used unncessarily.
Also, fixed a few places where we were missing ir.MarkFunc(), which sets
the class of a function node properly.
Change-Id: I6b02613039b16b507b44525faa2cd7031afb6982
Reviewed-on: https://go-review.googlesource.com/c/go/+/352069
Trust: Dan Scales <danscales@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
