Convert the scheduling pass from scheduling backwards to scheduling forwards.
Forward scheduling makes it easier to prioritize scheduling values as
soon as they are ready, which is important for things like nil checks,
select ops, etc.
Forward scheduling is also quite a bit clearer. It was originally
backwards because computing uses is tricky, but I found a way to do it
simply and with n lg n complexity. The new scheme also makes it easy
to add new scheduling edges if needed.
Fixes#42673
Update #56568
Change-Id: Ibbb38c52d191f50ce7a94f8c1cbd3cd9b614ea8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/270940
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The SPanchored opcode is identical to SP, except that it takes a memory
argument so that it (and more importantly, anything that uses it)
must be scheduled at or after that memory argument.
This opcode ensures that a LEAQ of a variable gets scheduled after the
corresponding VARDEF for that variable.
This may lead to less CSE of LEAQ operations. The effect is very small.
The go binary is only 80 bytes bigger after this CL. Usually LEAQs get
folded into load/store operations, so the effect is only for pointerful
types, large enough to need a duffzero, and have their address passed
somewhere. Even then, usually the CSEd LEAQs will be un-CSEd because
the two uses are on different sides of a function call and the LEAQ
ends up being rematerialized at the second use anyway.
Change-Id: Ib893562cd05369b91dd563b48fb83f5250950293
Reviewed-on: https://go-review.googlesource.com/c/go/+/452916
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Long ago we decided that panic(nil) was too unlikely to bother
making a special case for purposes of recover. Unfortunately,
it has turned out not to be a special case. There are many examples
of code in the Go ecosystem where an author has written panic(nil)
because they want to panic and don't care about the panic value.
Using panic(nil) in this case has the unfortunate behavior of
making recover behave as though the goroutine isn't panicking.
As a result, code like:
func f() {
defer func() {
if err := recover(); err != nil {
log.Fatalf("panicked! %v", err)
}
}()
call1()
call2()
}
looks like it guarantees that call2 has been run any time f returns,
but that turns out not to be strictly true. If call1 does panic(nil),
then f returns "successfully", having recovered the panic, but
without calling call2.
Instead you have to write something like:
func f() {
done := false
defer func() {
if err := recover(); !done {
log.Fatalf("panicked! %v", err)
}
}()
call1()
call2()
done = true
}
which defeats nearly the whole point of recover. No one does this,
with the result that almost all uses of recover are subtly broken.
One specific broken use along these lines is in net/http, which
recovers from panics in handlers and sends back an HTTP error.
Users discovered in the early days of Go that panic(nil) was a
convenient way to jump out of a handler up to the serving loop
without sending back an HTTP error. This was a bug, not a feature.
Go 1.8 added panic(http.ErrAbortHandler) as a better way to access the feature.
Any lingering code that uses panic(nil) to abort an HTTP handler
without a failure message should be changed to use http.ErrAbortHandler.
Programs that need the old, unintended behavior from net/http
or other packages can set GODEBUG=panicnil=1 to stop the run-time error.
Uses of recover that want to detect panic(nil) in new programs
can check for recover returning a value of type *runtime.PanicNilError.
Because the new GODEBUG is used inside the runtime, we can't
import internal/godebug, so there is some new machinery to
cross-connect those in this CL, to allow a mutable GODEBUG setting.
That won't be necessary if we add any other mutable GODEBUG settings
in the future. The CL also corrects the handling of defaulted GODEBUG
values in the runtime, for #56986.
Fixes#25448.
Change-Id: I2b39c7e83e4f7aa308777dabf2edae54773e03f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/461956
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
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Unified IR added several new IR fields for holding *runtime._type
expressions. To avoid throwing off any frontend semantics
(particularly inlining cost heuristics), they were marked as
`mknode:"-"` so that code wouldn't visit them.
Unfortunately, this has a bad interaction with the static init
inlining optimization, because the latter relies on ir.EditChildren to
substitute all parameters. This potentially includes dictionary
parameters, which can appear within the new RType fields.
This CL adds a new ir.EditChildrenWithHidden function that also edits
these fields, and switches staticinit to use it. Longer term, we
should unhide the RType fields so that ir.EditChildren visits them
normally, but that's scarier so late in the release cycle.
Fixes#57778.
Change-Id: I98c1e8cf366156dc0c81a0cb79029cc5e59c476f
Reviewed-on: https://go-review.googlesource.com/c/go/+/461686
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We need to avoid nospill registers at this point in regalloc.
Make sure that we don't restrict our register set to avoid registers
desired by other instructions, if the resulting set includes only
nospill registers.
Fixes#57846
Change-Id: I05478e4513c484755dc2e8621d73dac868e45a27
Reviewed-on: https://go-review.googlesource.com/c/go/+/461685
Reviewed-by: Keith Randall <khr@google.com>
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As we have seen many times, the type checker must be careful to avoid
accessing named type information before the type is fully set up. We
need a more systematic solution to this problem, but for now avoid one
case that causes a crash: checking a selector expression on an
incomplete type when a type expression is expected.
For golang/go#57522
Change-Id: I7ed31b859cca263276e3a0647d1f1b49670023a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/461577
Run-TryBot: Robert Findley <rfindley@google.com>
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These typos were found by executing grep, aspell, sort, and uniq in
a pipe and searching the resulting list manually for possible typos.
grep -r --include '*.go' -E '^// .*$' . | aspell list | sort | uniq
Change-Id: I56281eda3b178968fbf104de1f71316c1feac64f
GitHub-Last-Rev: e91c7cee34
GitHub-Pull-Request: golang/go#57669
Reviewed-on: https://go-review.googlesource.com/c/go/+/460767
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Per the latest spec, we distinguish between interface implementation
and constraint satisfaction. Use the verb "satisfy" when reporting
an error about failing constraint satisfaction.
This CL only changes error messages. It has no impact on correct code.
Fixes#57564.
Change-Id: I6dfb3b2093c2e04fe5566628315fb5f6bd709f17
Reviewed-on: https://go-review.googlesource.com/c/go/+/460396
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Devirtualization can turn OCALLINTER into OCALLMETH, but then we want
to actually desugar into OCALLFUNC instead for later phases. Just
needs a missing call to typecheck.FixMethodCall.
Fixes#57309.
Change-Id: I331fbd40804e1a370134ef17fa6dd501c0920ed3
Reviewed-on: https://go-review.googlesource.com/c/go/+/457715
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ARM64 maintains booleans in the low byte of registers. Upper parts
of that register are junk.
This rule is using all 32 bits of a boolean-containing register, which
is wrong. Change the rule to only look at the low bit.
Fixes#57184
Change-Id: Ibbef86b2be859df3d06d993db00e1231c481c428
Reviewed-on: https://go-review.googlesource.com/c/go/+/456556
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Change-Id: I4cff6b2a1fed6acdf754539c3c53a61eaa3b3f84
Reviewed-on: https://go-review.googlesource.com/c/go/+/450176
Auto-Submit: Ian Lance Taylor <iant@golang.org>
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CL 450136 added handling for simple calls in staticinit. If there's any
derived types conversion in the body of generic function called, that
conversion will require runtime dictionary, thus the optimization could
not happen.
Fixes#56923
Change-Id: I498cee9f8ab4397812ef79a6c2ab6c55e0ee4aef
Reviewed-on: https://go-review.googlesource.com/c/go/+/453315
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if q != nil {
p = &q.f
}
Which gets rewritten to a conditional move:
tmp := &q.f
p = Select q!=nil, tmp, p
Unfortunately, we can't compute &q.f before we've checked if q is nil,
because if it is nil, &q.f is an invalid pointer (if f's offset is
nonzero but small).
Normally this is not a problem because the tmp variable above
immediately dies, and is thus not live across any safepoint. However,
if later there is another &q.f computation, those two computations are
CSEd, causing tmp to be used at both use points. That will extend
tmp's lifetime, possibly across a call.
Fixes#56990
Change-Id: I3ea31be93feae04fbe3304cb11323194c5df3879
Reviewed-on: https://go-review.googlesource.com/c/go/+/454155
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This was disabled in CL 452676 out of an abundance of caution,
but further analysis has shown that the failures were not being
caused by this optimization. Instead the sequence of commits was:
CL 450136 cmd/compile: handle simple inlined calls in staticinit
...
CL 449937 archive/tar, archive/zip: return ErrInsecurePath for unsafe paths
...
CL 451555 cmd/compile: fix static init for inlined calls
The failures in question became compile failures in the first CL
and started building again after the last CL.
But in the interim the code had been broken by the middle CL.
CL 451555 was just the first time that the tests could run and fail.
For #30820.
Change-Id: I65064032355b56fdb43d9731be2f9f32ef6ee600
Reviewed-on: https://go-review.googlesource.com/c/go/+/452817
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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This CL adds -d=inlstaticinit to control whether static initialization
of inlined function calls (added in CL 450136) is allowed.
We've needed to fix it once already (CL 451555) and Google-internal
testing is hitting additional failure cases, so putting this
optimization behind a feature flag seems appropriate regardless.
Also, while we diagnose and fix the remaining cases, this CL also
disables the optimization to avoid miscompilations.
Updates #56894.
Change-Id: If52a358ad1e9d6aad1c74fac5a81ff9cfa5a3793
Reviewed-on: https://go-review.googlesource.com/c/go/+/452676
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This CL changes cmd/compile to reject anonymous interface cycles like:
type I interface { m() interface { I } }
We don't anticipate any users to be affected by this change in
practice. Nonetheless, this CL also adds a `-d=interfacecycles`
compiler flag to suppress the error. And assuming no issue reports
from users, we'll move the check into go/types and types2 instead.
Updates #56103.
Change-Id: I1f1dce2d7aa19fb388312cc020e99cc354afddcb
Reviewed-on: https://go-review.googlesource.com/c/go/+/445598
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The previous rule may move the phi value into a wrong block.
This CL make it only rewrite the phi value not the If block,
so that the phi value will stay in old block.
Fixes#56777
Change-Id: I9479a5c7f28529786968413d35b82a16181bb1f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/451496
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For implementing interface to empty interface conversion, the compiler
generate code like:
var res *uint8
res = itab
if res != nil {
res = res.type
}
However, itab has type *uintptr, so the assignment is broken. The
problem is not shown up, until CL 450215, which call typecheck on this
broken assignment.
To fix this, just cast itab to *uint8 when doing the conversion.
Fixes#56768
Change-Id: Id42792d18e7f382578b40854d46eecd49673792c
Reviewed-on: https://go-review.googlesource.com/c/go/+/451256
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CL 450136 made the compiler to be able to handle simple inlined calls in
staticinit. However, it's missed a condition when checking substituting
arg for param. If there's any non-trivial closures, it has captured one
of the param, so the substitution could not happen.
Fixes#56778
Change-Id: I427c9134e333e2f9af136c1a124da4d37d326f10
Reviewed-on: https://go-review.googlesource.com/c/go/+/451555
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Cl 426334 removed its only usage, and now we have gcflags_noopt.
Change-Id: I3b33a8c868669deea00bf6dfcf8d81981504e293
Reviewed-on: https://go-review.googlesource.com/c/go/+/451255
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Given code like
func itou(i int) uint { return uint(i) }
var x = itou(-1)
the static inliner from CL 450136 was rewriting the code to
var x = uint(-1)
which is not valid Go code. Fix this by converting the
constants appropriately during inlining.
Fixes golang.org/x/image/vector test.
Change-Id: I13448df8504c6a70525b1cdc36e2c947e22cdd33
Reviewed-on: https://go-review.googlesource.com/c/go/+/451376
Auto-Submit: Russ Cox <rsc@golang.org>
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Fix noopt build break from CL 450136 by not running test.
I can't reproduce the failure locally, but it's entirely reasonable
for this test to fail when optimizations are disabled, so just don't
run it when optimizations are disabled.
Change-Id: I882760fc7373ba0449379f81d295312a6be49be1
Reviewed-on: https://go-review.googlesource.com/c/go/+/450740
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Global variable initializers like
var myErr error = &myError{"msg"}
have been converted to statically initialized data
from the earliest days of Go: there is no init-time
execution or allocation for that line of code.
But if the expression is moved into an inlinable function,
the static initialization no longer happens.
That is, this code has always executed and allocated
at init time, even after we added inlining to the compiler,
which should in theory make this code equivalent to
the original:
func NewError(s string) error { return &myError{s} }
var myErr2 = NewError("msg")
This CL makes the static initialization rewriter understand
inlined functions consisting of a single return statement,
like in this example, so that myErr2 can be implemented as
statically initialized data too, just like myErr, with no init-time
execution or allocation.
A real example of code that benefits from this rewrite is
all globally declared errors created with errors.New, like
package io
var EOF = errors.New("EOF")
Package io no longer has to allocate and initialize EOF each
time a program starts.
Another example of code that benefits is any globally declared
godebug setting (using the API from CL 449504), like
package http
var http2server = godebug.New("http2server")
These are no longer allocated and initialized at program startup either.
The list of functions that are inlined into static initializers when
compiling std and cmd (along with how many times each occurs) is:
cmd/compile/internal/ssa.StringToAux (3)
cmd/compile/internal/walk.mkmapnames (4)
errors.New (360)
go/ast.NewIdent (1)
go/constant.MakeBool (4)
go/constant.MakeInt64 (3)
image.NewUniform (4)
image/color.ModelFunc (11)
internal/godebug.New (12)
vendor/golang.org/x/text/unicode/bidi.newBidiTrie (1)
vendor/golang.org/x/text/unicode/norm.newNfcTrie (1)
vendor/golang.org/x/text/unicode/norm.newNfkcTrie (1)
For the cmd/go binary, this CL cuts the number of init-time
allocations from about 1920 to about 1620 (a 15% reduction).
The total executable code footprint of init functions is reduced
by 24kB, from 137kB to 113kB (an 18% reduction).
The overall binary size is reduced by 45kB,
from 15.335MB to 15.290MB (a 0.3% reduction).
(The binary size savings is larger than the executable code savings
because every byte of executable code also requires corresponding
runtime tables for unwinding, source-line mapping, and so on.)
Also merge test/sinit_run.go, which had stopped testing anything
at all as of CL 161337 (Feb 2019) and initempty.go into a new test
noinit.go.
Fixes#30820.
Change-Id: I52f7275b1ac2a0a32e22c29f9095071c7b1fac20
Reviewed-on: https://go-review.googlesource.com/c/go/+/450136
Reviewed-by: Cherry Mui <cherryyz@google.com>
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CL 440455 fixed missing walk pass for static initialization slice.
However, slicelit may produce un-typechecked node, thus we need to do
typecheck for sinit before calling walkStmtList.
Fixes#56727
Change-Id: I40730cebcd09f2be4389d71c5a90eb9a060e4ab7
Reviewed-on: https://go-review.googlesource.com/c/go/+/450215
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Add a new SSA opcode ISELZ, similar to ISELB to represent a select
of value or 0. Then, merge candidate ISEL opcodes inside the late
lower pass.
This avoids complicating rules within the the lower pass.
Change-Id: I3b14c94b763863aadc834b0e910a85870c131313
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If an imported, non-generic function F transitively calls a generic
function G[T], we may need to call CanInline on G[T].
While here, we can also take advantage of the fact that we know G[T]
was already seen and compiled in an imported package, so we don't need
to call InlineCalls or add it to typecheck.Target.Decls. This saves us
from wasting compile time re-creating DUPOK symbols that we know
already exist in the imported package's link objects.
Fixes#56280.
Change-Id: I3336786bee01616ee9f2b18908738e4ca41c8102
Reviewed-on: https://go-review.googlesource.com/c/go/+/443535
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ISEL is roughly equivalent to CMOV on PPC64. Verify ISEL generation
in all reasonable cases.
Note "ISEL test x y z" is the same as "ISEL !test y x z". test is
always one of LT (0), GT (1), EQ (2), SO (3). Sometimes x and y are
swapped if GE/LE/NE is desired.
Change-Id: Ie1bf029224064e004d855099731fe5e8d05aa990
Reviewed-on: https://go-review.googlesource.com/c/go/+/445215
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Prior to Go 1.18, ineffectual //go:linkname directives (i.e.,
directives referring to an undeclared name, or to a declared type or
constant) were treated as noops. In Go 1.18, we changed this into a
compiler error to mitigate accidental misuse.
However, the x/sys repo contained ineffectual //go:linkname directives
up until go.dev/cl/274573, which has caused a lot of user confusion.
It seems a bit late to worry about now, but to at least prevent
further user pain, this CL changes the error message to only apply to
modules using "go 1.18" or newer. (The x/sys repo declared "go 1.12"
at the time go.dev/cl/274573 was submitted.)
Fixes#55889.
Change-Id: Id762fff96fd13ba0f1e696929a9e276dfcba2620
Reviewed-on: https://go-review.googlesource.com/c/go/+/447755
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This needs to be as low as possible while not breaking priority
assumptions of other scores to correctly schedule carry chains.
Prior to the arm64 changes, it was set below ReadTuple. At the time,
this prevented the MulHiLo implementation on PPC64 from occluding
the scheduling of a full carry chain.
Memory scores can also prevent better scheduling, as can be observed
with crypto/internal/edwards25519/field.feMulGeneric.
Fixes#56497
Change-Id: Ia4b54e6dffcce584faf46b1b8d7cea18a3913887
Reviewed-on: https://go-review.googlesource.com/c/go/+/447435
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
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Reviewed-by: Keith Randall <khr@golang.org>
The go1 benchmark suite does a lot of work at package init time, which
makes it take quite a while to run even if you're not running any of
the benchmarks, or if you're only running a subset of them. This leads
to an awkward workaround in dist test to compile but not run the
package, unlike roughly all other packages. It also reduces isolation
between benchmarks by affecting the starting heap size of all
benchmarks.
Fix this by initializing all data required by a benchmark when that
benchmark runs, and keeping it local so it gets freed by the GC and
doesn't leak between benchmarks. Now, none of the benchmarks depend on
global state.
Re-initializing the data on each benchmark run does add overhead to an
actual benchmark run, as each benchmark function is called several
times with different values of b.N. A full run of all benchmarks at
the default -benchtime=1s now takes ~10% longer; higher -benchtimes
would be less. It would be quite difficult to cache this data between
invocations of the same benchmark function without leaking between
different benchmarks and affecting GC overheads, as the testing
package doesn't provide any mechanism for this.
This reduces the time to run the binary with no benchmarks from 1.5
seconds to 10 ms, and also reduces the memory required to do this from
342 MiB to 17 MiB.
To make sure data was not leaking between different benchmarks, I ran
the benchmarks with -shuffle=on. The variance remained low: mostly
under 3%. A few benchmarks had higher variance, but in all cases it
was similar to the variance between this change.
This CL naturally changes the measured performance of several of the
benchmarks because it dramatically changes the heap size and hence GC
overheads. However, going forward the benchmarks should be much better
isolated.
For #37486.
Change-Id: I252ebea703a9560706cc1990dc5ad22d1927c7a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/443336
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Reviewed-by: Michael Pratt <mpratt@google.com>
Run-TryBot: Austin Clements <austin@google.com>
The recently added rule only works before decomposing slices.
Add a rule that works after decomposing slices.
The reason we need the latter is because although the length may
be a constant, it can be hidden inside a slice that is not constant
(its pointer or capacity might be changing). By applying this
optimization after decomposing slices, we can find more cases
where it applies.
Fixes#56440
Change-Id: I0094e59eee3065ab4d210defdda8227a6e897420
Reviewed-on: https://go-review.googlesource.com/c/go/+/446277
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
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Reviewed-by: Keith Randall <khr@google.com>
Fixes a performance regression due to CL 418554.
Fixes#56440
Change-Id: I6ff152e9b83084756363f49ee6b0844a7a284880
Reviewed-on: https://go-review.googlesource.com/c/go/+/445875
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
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Error messages currently print floats with %.6g, which means that if
you tried to convert something close to, but not quite, an integer, to
an integer, the error you get looks like "cannot convert 1 to type
int", when really you want "cannot convert 0.9999999 to type int".
Add more digits to floats when printing them, to make it clear that they
aren't quite integers. This helps for errors which are the result of not
being an integer. For other errors, it won't hurt much.
Fixes#56220
Change-Id: I7f5873af5993114a61460ef399d15316925a15a5
Reviewed-on: https://go-review.googlesource.com/c/go/+/442935
Reviewed-by: Rob Pike <r@golang.org>
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Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
Replace all uses of Ctz64/32/8 with TrailingZeros64/32/8, because they
are the same and maybe duplicated. Also renamed CtzXX functions in 386
assembly code.
Change-Id: I19290204858083750f4be589bb0923393950ae6d
Reviewed-on: https://go-review.googlesource.com/c/go/+/438935
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
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Reviewed-by: Keith Randall <khr@google.com>
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Using importcfg instead of depending on the existence of .a files for
standard library packages will enable us to remove the .a files in a
future cl.
Change-Id: I6108384224508bc37d82fd990fc4a8649222502c
Reviewed-on: https://go-review.googlesource.com/c/go/+/440222
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Michael Matloob <matloob@golang.org>
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fakePC uses hash.Sum32, which returns an uint32. However, libfuzzer
trace/hook functions declare fakePC argument as int, causing overflow on
386 archs.
Fixing this by changing fakePC argument to uint to prevent the overflow.
Fixes#56141
Change-Id: I3994c461319983ab70065f90bf61539a363e0a2a
Reviewed-on: https://go-review.googlesource.com/c/go/+/441996
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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For #56109
Change-Id: I999763e463fac57732a92f5e396f8fa8c35bd2e1
Reviewed-on: https://go-review.googlesource.com/c/go/+/440297
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
CL 403995 fixed static init of literal contains dynamic exprs, by
ensuring their init are ordered properly. However, we still need to walk
the generated init codes before appending to parent init. Otherwise,
codes that requires desugaring will be unhandled, causing the compiler
backend crashing.
Fixes#56105
Change-Id: Ic25fd4017473f5412c8e960a91467797a234edfd
Reviewed-on: https://go-review.googlesource.com/c/go/+/440455
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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Reviewed-by: Keith Randall <khr@golang.org>
For example:
movb a0, a0
srai $1, a0, a0
the assembler will expand to:
slli $56, a0, a0
srai $56, a0, a0
srai $1, a0, a0
this CL optimize to:
slli $56, a0, a0
srai $57, a0, a0
Remove 270+ instructions from Go binary on linux/riscv64.
Change-Id: I375e19f9d3bd54f2781791d8cbe5970191297dc8
Reviewed-on: https://go-review.googlesource.com/c/go/+/428496
Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
This is the last failed test in Unified IR, since it can inline f5 and
f6 but the old frontend can not. So marking them as //go:noinline, with
a TODO for re-enable once GOEXPERIMENT=nounified is gone.
Fixes#53058
Change-Id: Ifbbc49c87997a53e1b323048f0067f0257655fad
Reviewed-on: https://go-review.googlesource.com/c/go/+/437217
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
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The mismatch between Unified IR and the old frontend is not about how
they number the closures, but how they name them. For nested closure,
the old frontend use the immediate function which contains the closure
as the outer function, while Unified IR uses the outer most function as
the outer for all closures.
That said, what important is matching the number of closures, not their
name prefix. So this CL relax the test to match both "main.func1.func2"
and "main.func1.2" to satisfy both Unified IR and the old frontend.
Updates #53058
Change-Id: I66ed816d1968aa68dd3089a4ea5850ba30afd75b
Reviewed-on: https://go-review.googlesource.com/c/go/+/437216
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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The linker needs FuncInfo metadata for all inlined functions. This is
typically handled by gc.enqueueFunc calling ir.InitLSym for all function
declarations in typecheck.Target.Decls (ir.UseClosure adds all closures
to Decls).
However, non-trivial closures in Decls are ignored, and are insteaded
enqueued when walk of the calling function discovers them.
This presents a problem for direct calls to closures. Inlining will
replace the entire closure definition with its body, which hides the
closure from walk and thus suppresses symbol creation.
Explicitly create a symbol early in this edge case to ensure we keep
this metadata.
InitLSym needs to move out of ssagen to avoid a circular dependency (it
doesn't have anything to do with ssa anyway). There isn't a great place
for it, so I placed it in ir, which seemed least objectionable.
The added test triggers one of these inlined direct non-trivial closure
calls, though the test needs CL 429637 to fail, which adds a FuncInfo
assertion to the linker. Note that the test must use "run" instead of
"compile" since the assertion is in the linker, and "compiler" doesn't
run the linker.
Fixes#54959.
Change-Id: I0bd1db4f3539a78da260934cd968372b7aa92546
Reviewed-on: https://go-review.googlesource.com/c/go/+/436240
Run-TryBot: Michael Pratt <mpratt@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
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