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2224 Commits

Author SHA1 Message Date
Than McIntosh
0b07bbd2be cmd/compile/internal/inl: inline based on scoring when GOEXPERIMENT=newinliner
This patch changes the inliner to use callsite scores when deciding to
inline as opposed to looking only at callee cost/hairyness.

For this to work, we have to relax the inline budget cutoff as part of
CanInline to allow for the possibility that a given function might
start off with a cost of N where N > 80, but then be called from a
callsites whose score is less than 80. Once a given function F in
package P has been approved by CanInline (based on the relaxed budget)
it will then be emitted as part of the export data, meaning that other
packages importing P will need to also need to compute callsite scores
appropriately.

For a function F that calls function G, if G is marked as potentially
inlinable then the hairyness computation for F will use G's cost for
the call to G as opposed to the default call cost; for this to work
with the new scheme (given relaxed cost change described above) we
use G's cost only if it falls below inlineExtraCallCost, otherwise
just use inlineExtraCallCost.

Included in this patch are a bunch of skips and workarounds to
selected 'errorcheck' tests in the <GOROOT>/test directory to deal
with the additional "can inline" messages emitted when the new inliner
is turned on.

Change-Id: I9be5f8cd0cd8676beb4296faf80d2f6be7246335
Reviewed-on: https://go-review.googlesource.com/c/go/+/519197
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2023-09-14 19:43:26 +00:00
Matthew Dempsky
2e457b3868 cmd/compile/internal/noder: handle unsafe.Sizeof, etc in unified IR
Previously, the unified frontend implemented unsafe.Sizeof, etc that
involved derived types by constructing a normal OSIZEOF, etc
expression, including fully instantiating their argument. (When
unsafe.Sizeof is applied to a non-generic type, types2 handles
constant folding it.)

This worked, but involves unnecessary work, since all we really need
to track is the argument type (and the field selections, for
unsafe.Offsetof).

Further, the argument expression could generate temporary variables,
which would then go unused after typecheck replaced the OSIZEOF
expression with an OLITERAL. This results in compiler failures after
CL 523315, which made later passes stricter about expecting the
frontend to not construct unused temporaries.

Fixes #62515.

Change-Id: I37baed048fd2e35648c59243f66c97c24413aa94
Reviewed-on: https://go-review.googlesource.com/c/go/+/527097
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
2023-09-11 20:48:07 +00:00
Matthew Dempsky
afa3f8e104 cmd/compile/internal/staticinit: make staticopy safe
Currently, cmd/compile optimizes `var a = true; var b = a` into `var a
= true; var b = true`. But this may not be safe if we need to
initialize any other global variables between `a` and `b`, and the
initialization involves calling a user-defined function that reassigns
`a`.

This CL changes staticinit to keep track of the initialization
expressions that we've seen so far, and to stop applying the
staticcopy optimization once we've seen an initialization expression
that might have modified another global variable within this package.

To help identify affected initializers, this CL adds a -d=staticcopy
flag to warn when a staticcopy is suppressed and turned into a dynamic
copy.

Currently, `go build -gcflags=all=-d=staticcopy std` reports only four
instances:

```
encoding/xml/xml.go:1600:5: skipping static copy of HTMLEntity+0 with map[string]string{...}
encoding/xml/xml.go:1869:5: skipping static copy of HTMLAutoClose+0 with []string{...}
net/net.go:661:5: skipping static copy of .stmp_31+0 with poll.ErrNetClosing
net/http/transport.go:2566:5: skipping static copy of errRequestCanceled+0 with ~R0
```

Fixes #51913.

Change-Id: Iab41cf6f84c44f7f960e4e62c28a8aeaade4fbcf
Reviewed-on: https://go-review.googlesource.com/c/go/+/395541
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
2023-09-11 20:12:05 +00:00
Matthew Dempsky
e3ce312621 cmd/compile/internal/typecheck: fix closure field naming
When creating the struct type to hold variables captured by a function
literal, we currently reuse the captured variable names as fields.

However, there's no particular reason to do this: these struct types
aren't visible to users, and it adds extra complexity in making sure
fields belong to the correct packages.

Further, it turns out we were getting that subtly wrong. If two
function literals from different packages capture variables with
identical names starting with an uppercase letter (and in the same
order and with corresponding identical types) end up in the same
function (e.g., due to inlining), then we could end up creating
closure struct types that are "different" (i.e., not types.Identical)
yet end up with equal LinkString representations (which violates
LinkString's contract).

The easy fix is to just always use simple, exported, generated field
names in the struct. This should allow further struct reuse across
packages too, and shrink binary sizes slightly.

Fixes #62498.

Change-Id: I9c973f5087bf228649a8f74f7dc1522d84a26b51
Reviewed-on: https://go-review.googlesource.com/c/go/+/527135
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
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2023-09-11 16:02:11 +00:00
Matthew Dempsky
18c6ec1e4a cmd/compile/internal/noder: stop preserving original const strings
One of the more tedious quirks of the original frontend (i.e.,
typecheck) to preserve was that it preserved the original
representation of constants into the backend. To fit into the unified
IR model, I ended up implementing a fairly heavyweight workaround:
simply record the original constant's string expression in the export
data, so that diagnostics could still report it back, and match the
old test expectations.

But now that there's just a single frontend to support, it's easy
enough to just update the test expectations and drop this support for
"raw" constant expressions.

Change-Id: I1d859c5109d679879d937a2b213e777fbddf4f2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/526376
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
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Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2023-09-08 18:50:24 +00:00
Keith Randall
fb5bdb4cc9 cmd/compile: absorb InvertFlags into Noov comparisons
Unfortunately, there isn't a single op that provides the resulting
computation.
At least, I couldn't find one.

Fixes #62469

Change-Id: I236f3965b827aaeb3d70ef9fe89be66b116494f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/526276
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2023-09-07 15:14:39 +00:00
Keith Randall
0e02baa59a Revert "cmd/compile: use shorter ANDL/TESTL if upper 32 bits are known to be zero"
This reverts commit c1dfbf72e1.

Reason for revert: TESTL rule is wrong when the result is used for an ordered comparison.

Fixes #62360

Change-Id: I4d5b6aca24389b0a2bf767bfbc0a9d085359eb38
Reviewed-on: https://go-review.googlesource.com/c/go/+/524255
Run-TryBot: Keith Randall <khr@golang.org>
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Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
2023-08-30 15:15:28 +00:00
Matthew Dempsky
4f97a7e6ea cmd/compile/internal/ir: set Addrtaken on Canonical ONAME too
In CL 522879, I moved the logic for setting Addrtaken from typecheck's
markAddrOf and ComputeAddrtaken directly into ir.NewAddrExpr. However,
I took the logic from markAddrOf, and failed to notice that
ComputeAddrtaken also set Addrtaken on the canonical ONAME.

The result is that if the only address-of expressions were within a
function literal, the canonical variable never got marked Addrtaken.
In turn, this could cause the consistency check in ir.Reassigned to
fail. (Yay for consistency checks turning mistakes into ICEs, rather
than miscompilation.)

Fixes #62313.

Change-Id: Ieab2854cd7fcc1b6c5d1e61de66453add9890a4f
Reviewed-on: https://go-review.googlesource.com/c/go/+/523375
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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2023-08-28 14:32:14 +00:00
Keith Randall
b303fb4855 runtime: fix maps.Clone bug when cloning a map mid-grow
Fixes #62203

Change-Id: I0459d3f481b0cd20102f6d9fd3ea84335a7739a8
Reviewed-on: https://go-review.googlesource.com/c/go/+/522317
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
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2023-08-25 16:10:03 +00:00
Bryan C. Mills
5374c1aaf5 cmd/internal/testdir: parse past gofmt'd //go:build lines
Also gofmt a test file to make sure the parser works.

Fixes #62267.

Change-Id: I9b9f12b06bae7df626231000879b5ed7df3cd9ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/522635
Reviewed-by: Ian Lance Taylor <iant@google.com>
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2023-08-24 17:52:48 +00:00
Bryan C. Mills
fe2c686b63 test/fixedbugs: require cgo for issue10607.go
This test passes "-linkmode=external" to 'go run' to link the binary
using the system C linker.

CGO_ENABLED=0 explicitly tells cmd/go not to use the C toolchain,
so the test should not be run in that configuration.

Updates #46330.

Change-Id: I16ac66aac91178045f9decaeb28134061e9711f7
Reviewed-on: https://go-review.googlesource.com/c/go/+/522495
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
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2023-08-24 17:19:11 +00:00
Matthew Dempsky
2c51ea11b0 cmd/compile/internal/typecheck: push ONEW into go/defer wrappers
Currently, we rewrite:

	go f(new(T))

into:

	tmp := new(T)
	go func() { f(tmp) }()

However, we can both shrink the closure and improve escape analysis by
instead rewriting it into:

	go func() { f(new(T)) }()

This CL does that.

Change-Id: Iae16a476368da35123052ca9ff41c49159980458
Reviewed-on: https://go-review.googlesource.com/c/go/+/520340
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2023-08-17 19:37:04 +00:00
Matthew Dempsky
7e2e648a2d cmd/compile/internal/typecheck: normalize go/defer statements earlier
Normalizing go/defer statements to always use functions with zero
parameters and zero results was added to escape analysis, because that
was the earliest point at which all three frontends converged. Now
that we only have the unified frontend, we can do it during typecheck,
which is where we perform all other desugaring and normalization
rewrites.

Change-Id: Iebf7679b117fd78b1dffee2974bbf85ebc923b23
Reviewed-on: https://go-review.googlesource.com/c/go/+/520260
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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2023-08-17 19:36:58 +00:00
David Chase
e72ecc6a6b cmd/compile: in expandCalls, move all arg marshalling into call block
For aggregate-typed arguments passed to a call, expandCalls
decomposed them into parts in the same block where the value
was created.  This is not necessarily the call block, and in
the case where stores are involved, can change the memory
leaving that block, and getting that right is problematic.

Instead, do all the expanding in the same block as the call,
which avoids the problems of (1) not being able to reorder
loads/stores across a block boundary to conform to memory
order and (2) (incorrectly, not) exposing the new memory to
consumers in other blocks.  Putting it all in the same block
as the call allows reordering, and the call creates its own
new memory (which is already dealt with correctly).

Fixes #61992.

Change-Id: Icc7918f0d2dd3c480cc7f496cdcd78edeca7f297
Reviewed-on: https://go-review.googlesource.com/c/go/+/519276
Reviewed-by: Keith Randall <khr@google.com>
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2023-08-16 15:40:52 +00:00
Cuong Manh Le
b2a56b7053 cmd/compile: make backingArrayPtrLen to return typecheck-ed nodes
Fixes #61908

Change-Id: Ief8e3a6c42c0644c9f71ebef5f28a294cd7c153f
Reviewed-on: https://go-review.googlesource.com/c/go/+/517936
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2023-08-09 19:30:45 +00:00
Matthew Dempsky
8c5a54f698 cmd/compile: keep all open-coded defer slots as used
Open-coded defer slots are assigned indices upfront, so they're
logically like elements in an array. Without reassigning the indices,
we need to keep all of the elements alive so their relative offsets
are correct.

Fixes #61895.

Change-Id: Ie0191fdb33276f4e8ed0becb69086524fff022b2
Reviewed-on: https://go-review.googlesource.com/c/go/+/517856
Reviewed-by: Keith Randall <khr@google.com>
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2023-08-09 16:43:33 +00:00
Cuong Manh Le
ea565f156b cmd/compile: fix missing init nodes for len(string([]byte)) optimization
CL 497276 added optimization for len(string([]byte)) by avoiding call to
slicebytetostring. However, the bytes to string expression may contain
init nodes, which need to be preserved. Otherwise, it would make the
liveness analysis confusing about the lifetime of temporary variables
created by init nodes.

Fixes #61778

Change-Id: I6d1280a7d61bcc75f11132af41bda086f084ab54
Reviewed-on: https://go-review.googlesource.com/c/go/+/516375
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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2023-08-07 03:12:29 +00:00
Cherry Mui
5f9412911b cmd/internal/obj: print relocation type by name in -S output
The compiler/assembler's -S output prints relocation type
numerically, which is hard to understand. Every time I need to
count the relocation type constants to figure out which relocation
it actually is. Print the symbolic name instead.

Change-Id: I4866873bbae8b3dc0ee212609cb00280f9164243
Reviewed-on: https://go-review.googlesource.com/c/go/+/501856
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2023-07-20 19:42:11 +00:00
Cuong Manh Le
0b65b02ba5 cmd/compile: fix clear on slice with zero size elem
Fixed #61127

Change-Id: If07b04ebcc98438c66f273c0c94bea1f230dc2e8
Reviewed-on: https://go-review.googlesource.com/c/go/+/507535
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
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2023-07-10 16:31:54 +00:00
Keith Randall
c4db811e44 cmd/compile: don't ICE on unaligned offsets for pointer writes
User code is unlikely to be correct, but don't crash the compiler
when the offset of a pointer in an object is not a multiple of the
pointer size.

Fixes #61187

Change-Id: Ie56bfcb38556c5dd6f702ae4ec1d4534c6acd420
Reviewed-on: https://go-review.googlesource.com/c/go/+/508555
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2023-07-10 16:29:42 +00:00
Matthew Dempsky
79d4defa75 cmd/compile/internal/ssagen: fix min/max codegen, again
The large-function phi placement algorithm evidently doesn't like the
same pseudo-variable being used to represent expressions of varying
types.

Instead, use the same tactic as used for "valVar" (ssa.go:6585--6587),
which is to just generate a fresh marker node each time.

Maybe we could just use the OMIN/OMAX nodes themselves as the key
(like we do for OANDAND/OOROR), but that just seems needlessly risky
for negligible memory savings. Using fresh marker values each time
seems obviously safe by comparison.

Fixes #61041.

Change-Id: Ie2600c9c37b599c2e26ae01f5f8a433025d7fd08
Reviewed-on: https://go-review.googlesource.com/c/go/+/506679
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2023-06-28 16:07:47 +00:00
Cuong Manh Le
4ad4128d3c cmd/compile: fix bad order of evaluation for min/max builtin
For float or string, min/max builtin performs a runtime call, so we need
to save its result to temporary variable. Otherwise, the runtime call
will clobber closure's arguments currently on the stack when passing
min/max as argument to closures.

Fixes #60990

Change-Id: I1397800f815ec7853182868678d0f760b22afff2
Reviewed-on: https://go-review.googlesource.com/c/go/+/506115
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2023-06-27 18:18:23 +00:00
Cuong Manh Le
b3ca8d2b3c types2, go/types: record final type for min/max arguments
Fixes #60991

Change-Id: I6130ccecbdc209996dbb376491be9df3b8988327
Reviewed-on: https://go-review.googlesource.com/c/go/+/506055
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2023-06-26 17:08:05 +00:00
Keith Randall
a031f4ef83 cmd/compile: fix min/max builtin code generation
Our large-function phi placement algorithm is incompatible with phi
opcodes already existing in the SSA representation. Instead, use simple
variable assignments and have the phi placement algorithm place the phis
we need for min/max.

Turns out the small-function phi placement algorithm doesn't have this
sensitivity, so this bug only occurs in large functions (>500 basic blocks).

Maybe we should document/check that no phis are present when we start
phi placement (regardless of size).  Leaving for a potential separate CL.

We should probably also fix the placement algorithm to handle existing
phis correctly.  But this CL is probably a lot smaller/safer than
messing with phi placement.

Fixes #60982

Change-Id: I59ba7f506c72b22bc1485099a335d96315ebef67
Reviewed-on: https://go-review.googlesource.com/c/go/+/505756
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2023-06-24 05:24:25 +00:00
Cuong Manh Le
6dce882b3a cmd/compile: scanning closures body when visiting wrapper function
CL 410344 fixed missing method value wrapper, by visiting body of
wrapper function after applying inlining pass.

CL 492017 allow more inlining of functions that construct closures,
which ends up making the wrapper function now inlineable, but can
contain closure nodes that couldn't be inlined. These closures body may
contain OMETHVALUE nodes that we never seen, thus we need to scan
closures body for finding them.

Fixes #60945

Change-Id: Ia1e31420bb172ff87d7321d2da2989ef23e6ebb6
Reviewed-on: https://go-review.googlesource.com/c/go/+/505255
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2023-06-23 14:29:16 +00:00
Ian Lance Taylor
633b742ae0 test: add test that caused a gofrontend crash
Change-Id: Idd872c5b90dbca564ed8a37bb3683e642142ae63
Reviewed-on: https://go-review.googlesource.com/c/go/+/505015
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2023-06-21 21:30:46 +00:00
Cuong Manh Le
60e6afb689 cmd/compile: do not report division by error during typecheck
types2 have already errored about any spec-required overflows, and
division by zero. CL 469595 unintentionally fixed typecheck not to error
about overflows, but zero division is still be checked during tcArith.
This causes unsafe operations with variable size failed to compile,
instead of raising runtime error.

Fixes #60601

Change-Id: I7bea2821099556835c920713397f7c5d8a4025ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/501735
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2023-06-15 18:41:09 +00:00
Cuong Manh Le
96d16803c2 cmd/compile: allow ir.OMIN/ir.OMAX in mayCall
CL 496257 adds min/max builtins, which may appear as argument to a
function call, so it will be tested by mayCall. But those ops are not
handled by mayCall, causes the compiler crashes.

Fixes #60582

Change-Id: I729f10bf62b4aad39ffcb1433f576e74d09fdd9a
Reviewed-on: https://go-review.googlesource.com/c/go/+/500575
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2023-06-05 03:11:36 +00:00
Cherry Mui
fdb3dc471d cmd/internal/obj/arm: handle HAUTO etc. in addpool
HAUTO should be handled the same way as other stack offsets for
adding to constant pool. Add the missing cases.

Fixes #57955.

Change-Id: If7fc82cafb2bbf0a6121e73e353b8825cb36b5bc
Reviewed-on: https://go-review.googlesource.com/c/go/+/463138
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2023-06-01 19:29:08 +00:00
Austin Clements
c2e0bf0abf cmd/internal/testdir: pass if GOEXPERIMENT=cgocheck2 is set
Some testdir tests fail if GOEXPERIMENT=cgocheck2 is set. Fix this by
skipping these tests.

Change-Id: I58d4ef0cceb86bcf93220b4a44de9b9dc4879b16
Reviewed-on: https://go-review.googlesource.com/c/go/+/499675
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2023-06-01 18:30:44 +00:00
Robert Griesemer
1dd24d8216 go/types, types2: don't infer type argument for unused parameter in interfaces
Two interface types that are assignable don't have to be identical;
specifically, if they are defined types, they can be different
defined types. If those defined types specify type parameters which
are never used, do not infer a type argument based on the instantiation
of a matching defined type.

Adjusted three existing tests where we inferred type arguments incorrectly.

Fixes #60377.

Change-Id: I91fb207235424b3cbc42b5fd93eee619e7541cb7
Reviewed-on: https://go-review.googlesource.com/c/go/+/498315
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2023-05-25 21:37:01 +00:00
Derek Parker
c5ba9d2232 cmd/compile: prioritize non-CALL struct member comparisons
This patch optimizes reflectdata.geneq to pick apart structs in array
equality and prioritize non-CALL comparisons over those which involve
a runtime function call. This is similar to how arrays of strings
operate currently. Instead of looping over the entire array of structs
once, if there are any comparisons which involve a runtime function
call we instead loop twice. The first loop is all simple, quick
comparisons. If no inequality is found in the first loop the second loop
calls runtime functions for larger memory comparison, which is more
expensive.

For the benchmarks added in this change:

Old:

```
goos: linux
goarch: amd64
pkg: cmd/compile/internal/reflectdata
cpu: AMD Ryzen 9 3950X 16-Core Processor
BenchmarkEqArrayOfStructsEq
BenchmarkEqArrayOfStructsEq-32            797196              1497 ns/op
BenchmarkEqArrayOfStructsEq-32            758332              1581 ns/op
BenchmarkEqArrayOfStructsEq-32            764871              1599 ns/op
BenchmarkEqArrayOfStructsEq-32            760706              1558 ns/op
BenchmarkEqArrayOfStructsEq-32            763112              1476 ns/op
BenchmarkEqArrayOfStructsEq-32            747696              1547 ns/op
BenchmarkEqArrayOfStructsEq-32            756526              1562 ns/op
BenchmarkEqArrayOfStructsEq-32            768829              1486 ns/op
BenchmarkEqArrayOfStructsEq-32            764248              1477 ns/op
BenchmarkEqArrayOfStructsEq-32            752767              1545 ns/op
BenchmarkEqArrayOfStructsNotEq
BenchmarkEqArrayOfStructsNotEq-32         757194              1542 ns/op
BenchmarkEqArrayOfStructsNotEq-32         748942              1552 ns/op
BenchmarkEqArrayOfStructsNotEq-32         766687              1554 ns/op
BenchmarkEqArrayOfStructsNotEq-32         732069              1541 ns/op
BenchmarkEqArrayOfStructsNotEq-32         759163              1576 ns/op
BenchmarkEqArrayOfStructsNotEq-32         796402              1629 ns/op
BenchmarkEqArrayOfStructsNotEq-32         726610              1570 ns/op
BenchmarkEqArrayOfStructsNotEq-32         735770              1584 ns/op
BenchmarkEqArrayOfStructsNotEq-32         745255              1610 ns/op
BenchmarkEqArrayOfStructsNotEq-32         743872              1591 ns/op
PASS
ok      cmd/compile/internal/reflectdata        35.446s
```

New:

```
goos: linux
goarch: amd64
pkg: cmd/compile/internal/reflectdata
cpu: AMD Ryzen 9 3950X 16-Core Processor
BenchmarkEqArrayOfStructsEq
BenchmarkEqArrayOfStructsEq-32            618379              1827 ns/op
BenchmarkEqArrayOfStructsEq-32            619368              1922 ns/op
BenchmarkEqArrayOfStructsEq-32            616023              1910 ns/op
BenchmarkEqArrayOfStructsEq-32            617575              1905 ns/op
BenchmarkEqArrayOfStructsEq-32            610399              1889 ns/op
BenchmarkEqArrayOfStructsEq-32            615378              1823 ns/op
BenchmarkEqArrayOfStructsEq-32            613732              1883 ns/op
BenchmarkEqArrayOfStructsEq-32            613924              1894 ns/op
BenchmarkEqArrayOfStructsEq-32            657799              1876 ns/op
BenchmarkEqArrayOfStructsEq-32            665580              1873 ns/op
BenchmarkEqArrayOfStructsNotEq
BenchmarkEqArrayOfStructsNotEq-32        1834915               627.4 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1806370               660.5 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1828075               625.5 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1819741               641.6 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1813128               632.3 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1865250               643.7 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1828617               632.8 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1862748               633.6 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1825432               638.7 ns/op
BenchmarkEqArrayOfStructsNotEq-32        1804382               628.8 ns/op
PASS
ok      cmd/compile/internal/reflectdata        36.571s
```

Benchstat comparison:

```
name                      old time/op  new time/op  delta
EqArrayOfStructsEq-32     1.53µs ± 4%  1.88µs ± 3%  +22.66%  (p=0.000 n=10+10)
EqArrayOfStructsNotEq-32  1.57µs ± 3%  0.64µs ± 4%  -59.59%  (p=0.000 n=10+10)
```

So, the equal case is a bit slower (unrolling the loop helps with that),
but the non-equal case is now much faster.

Change-Id: I05d776456c79c48a3d6d74b18c45246e58ffbea6
GitHub-Last-Rev: f57ee07d05
GitHub-Pull-Request: golang/go#59409
Reviewed-on: https://go-review.googlesource.com/c/go/+/481895
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2023-05-24 21:55:14 +00:00
Robert Griesemer
956d31ecd5 cmd/compile: enable more lenient type inference for untyped arguments
This enables the implementation for proposal #58671, which is
a likely accept. By enabling it early we get a bit extra soak
time for this feature. The change can be reverted trivially, if
need be.

For #58671.

Change-Id: Id6c27515e45ff79f4f1d2fc1706f3f672ccdd1ab
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2023-05-18 00:35:53 +00:00
Than McIntosh
89138ce740 cmd/compile: un-hide closure func if parent expr moved to staticinit
If the function referenced by a closure expression is incorporated
into a static init, be sure to mark it as non-hidden, since otherwise
it will be live but no longer reachable from the init func, hence it
will be skipped during escape analysis, which can lead to
miscompilations.

Fixes #59680.

Change-Id: Ib858aee296efcc0b7655d25c23ab8a6a8dbdc5f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/492135
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2023-05-05 21:04:38 +00:00
Than McIntosh
ea69de9b92 cmd/compile: rework marking of dead hidden closure functions
[This is a roll-forward of CL 484859, this time including a fix for
issue #59709. The call to do dead function marking was taking place in
the wrong spot, causing it to run more than once if generics were
instantiated.]

This patch generalizes the code in the inliner that marks unreferenced
hidden closure functions as dead. Rather than doing the marking on the
fly (previous approach), this new approach does a single pass at the
end of inlining, which catches more dead functions.

Change-Id: I0e079ad755c21295477201acbd7e1a732a98fffd
Reviewed-on: https://go-review.googlesource.com/c/go/+/492016
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2023-05-05 21:04:28 +00:00
Matthew Dempsky
767fbe01ae cmd/compile: fix compilation of inferred type arguments
Previously, type arguments could only be inferred for generic
functions in call expressions, whereas with the reverse type inference
proposal they can now be inferred in assignment contexts too. As a
consequence, we now need to check Info.Instances to find the inferred
type for more cases now.

Updates #59338.
Fixes #59955.

Change-Id: I9b6465395869459c2387d0424febe7337b28b90e
Reviewed-on: https://go-review.googlesource.com/c/go/+/492455
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2023-05-03 22:12:27 +00:00
Robert Griesemer
1f570787a8 cmd/compile: enable reverse type inference
For #59338.

Change-Id: I8141d421cdc60e47ee5794fc1ca81246bd8a8a25
Reviewed-on: https://go-review.googlesource.com/c/go/+/491475
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2023-05-03 19:36:20 +00:00
Robert Griesemer
d93f02010c cmd/compile/internal/types2: only mark variables as used if they are
Marking variables in erroneous variable declarations as used is
convenient for tests but doesn't necessarily hide follow-on errors
in real code: either the variable is not supposed to be declared in
the first place and then we should get an error if it is not used,
or it is there because it is intended to be used, and the we expect
an error it if is not used.

This brings types2 closer to go/types.

Change-Id: If7ee1298fc770f7ad0cefe7e968533fd50ec2343
Reviewed-on: https://go-review.googlesource.com/c/go/+/486175
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2023-04-19 14:07:00 +00:00
Than McIntosh
7c1ed1fa8f Revert "cmd/compile: rework marking of dead hidden closure functions"
This reverts commit http://go.dev/cl//484859

Reason for revert: causes linker errors in a number of google-internal tests.

Change-Id: I322252f784a46d2b1d447ebcdca86ce14bc0cc91
Reviewed-on: https://go-review.googlesource.com/c/go/+/485755
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2023-04-18 16:03:22 +00:00
Than McIntosh
d240226fe5 cmd/compile: rework marking of dead hidden closure functions
This patch generalizes the code in the inliner that marks unreferenced
hidden closure functions as dead. Rather than doing the marking on the
fly (previous approach), this new approach does a single pass at the
end of inlining, which catches more dead functions.

Fixes #59638.
Updates #59404.
Updates #59547.

Change-Id: I54fd63e9e37c9123b08a3e7def7d1989919bba91
Reviewed-on: https://go-review.googlesource.com/c/go/+/484859
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2023-04-17 14:52:32 +00:00
Cuong Manh Le
20c349e534 cmd/compile: reenable inline static init
Updates #58293
Updates #58339
Fixes #58439

Change-Id: I06d2d92f86fa4a672d69515c4066d69d3e0fc75b
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2023-04-14 17:57:36 +00:00
Cuong Manh Le
a141c58c85 cmd/compile: handle string concatenation in static init inliner
Static init inliner is using typecheck.EvalConst to handle string
concatenation expressions. But static init inliner may reveal constant
expressions after substitution, and the compiler needs to evaluate those
expressions in non-constant semantic. Using typecheck.EvalConst, which
always evaluates expressions in constant semantic, is not the right
choice.

For safety, this CL fold the logic to handle string concatenation to
static init inliner, so there won't be regression in handling constant
expressions in non-constant semantic. And also, future CL can simplify
typecheck.EvalConst logic.

Updates #58293
Updates #58339
Fixes #58439

Change-Id: I74068d99c245938e576afe9460cbd2b39677bbff
Reviewed-on: https://go-review.googlesource.com/c/go/+/466277
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2023-04-14 17:57:14 +00:00
Keith Randall
2b92c39fe0 cmd/link: establish dependable package initialization order
(This is a retry of CL 462035 which was reverted at 474976.
The only change from that CL is the aix fix SRODATA->SNOPTRDATA
at inittask.go:141)

As described here:

https://github.com/golang/go/issues/31636#issuecomment-493271830

"Find the lexically earliest package that is not initialized yet,
but has had all its dependencies initialized, initialize that package,
 and repeat."

Simplify the runtime a bit, by just computing the ordering required
in the linker and giving a list to the runtime.

Update #31636
Fixes #57411

RELNOTE=yes

Change-Id: I28c09451d6aa677d7394c179d23c2c02c503fc56
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2023-04-14 16:55:22 +00:00
Junwei Zuo
89567a35c1 cmd/compile: fix ir.StaticValue for ORANGE
Range statement will mutate the key and value, so we should treat them as reassigned.

Fixes #59572

Change-Id: I9c6b67d938760a0c6a1d9739f2737c67af4a3a10
Reviewed-on: https://go-review.googlesource.com/c/go/+/483855
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2023-04-12 19:28:47 +00:00
Johan Brandhorst-Satzkorn
319b75ed33 all: add wasip1 support
Fixes #58141

Co-authored-by: Richard Musiol <neelance@gmail.com>
Co-authored-by: Achille Roussel <achille.roussel@gmail.com>
Co-authored-by: Julien Fabre <ju.pryz@gmail.com>
Co-authored-by: Evan Phoenix <evan@phx.io>
Change-Id: I49b66946acc90fdf09ed9223096bfec9a1e5b923
Reviewed-on: https://go-review.googlesource.com/c/go/+/479627
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2023-04-11 20:56:32 +00:00
Cuong Manh Le
231f290e51 runtime: mark map bucket slots as empty during map clear
So iterators that are in progress can know entries have been deleted and
terminate the iterator properly.

Update #55002
Update #56351
Fixes #59411

Change-Id: I924f16a00fe4ed6564f730a677348a6011d3fb67
Reviewed-on: https://go-review.googlesource.com/c/go/+/481935
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2023-04-08 05:25:04 +00:00
Keith Randall
b3bc8620f8 cmd/compile: use correct type for byteswaps on multi-byte stores
Use the type of the store for the byteswap, not the type of the
store's value argument.

Normally when we're storing a 16-bit value, the value being stored is
also typed as 16 bits. But sometimes it is typed as something smaller,
usually because it is the result of an upcast from a smaller value,
and that upcast needs no instructions.

If the type of the store's arg is thinner than the type being stored,
and the byteswap'd value uses that thinner type, and the byteswap'd
value needs to be spilled & restored, that spill/restore happens using
the thinner type, which causes us to lose some of the top bits of the
value.

Fixes #59367

Change-Id: If6ce1e8a76f18bf8e9d79871b6caa438bc3cce4d
Reviewed-on: https://go-review.googlesource.com/c/go/+/481395
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2023-04-07 21:11:29 +00:00
Than McIntosh
f1caf1aa1c cmd/compile: deadcode unreferenced hidden closures during inlining
When a closure is inlined, it may contain other hidden closures, which
the inliner will duplicate, rendering the original nested closures as
unreachable. Because they are unreachable, they don't get processed in
escape analysis, meaning that go/defer statements don't get rewritten,
which can then in turn trigger errors in walk. This patch looks for
nested hidden closures and marks them as dead, so that they can be
skipped later on in the compilation flow.  NB: if during escape
analysis we rediscover a hidden closure (due to an explicit reference)
that was previously marked dead, revive it at that point.

Fixes #59404.

Change-Id: I76db1e9cf1ee38bd1147aeae823f916dbbbf081b
Reviewed-on: https://go-review.googlesource.com/c/go/+/482355
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2023-04-07 15:07:18 +00:00
Cuong Manh Le
1e5955aabd cmd/compile: don't set range expr key/value type if already set
Unified IR already records the correct type for them.

Fixes #59378

Change-Id: I275c45b48f67bde55c8e2079d60b5868d0acde7f
Reviewed-on: https://go-review.googlesource.com/c/go/+/481555
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2023-04-05 17:48:15 +00:00
Keith Randall
8edcdddb23 crypto/subtle: don't cast to *uintptr when word size is 0
Casting to a *uintptr is not ok if there isn't at least 8 bytes of
data backing that pointer (on 64-bit archs).
So although we end up making a slice of 0 length with that pointer,
the cast itself doesn't know that.
Instead, bail early if the result is going to be 0 length.

Fixes #59334

Change-Id: Id3c0e09d341d838835c0382cccfb0f71dc3dc7e6
Reviewed-on: https://go-review.googlesource.com/c/go/+/480575
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2023-03-31 23:25:07 +00:00