Follow-up on CL 462856 which missed a few places.
Fixed manually.
Change-Id: I924560ecae8923d9228027016805a3cc892f8ac2
Reviewed-on: https://go-review.googlesource.com/c/go/+/463749
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When coming from C, the bitwise integer complement (bitwise negation)
operator is ~, but in Go it is ^. Report an error mentioning ^ when
~ is used with an integer operand.
Background: Some articles on the web claim that Go doesn't have a
bitwise complement operator.
Change-Id: I41185cae4a70d528754e44f42c13c013ed91bf27
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Allocate all handles up-front: in a correct program, all type parameters
must be resolved and thus eventually will get a handle.
Also, sharing of handles caused by unified type parameters is rare and
so it's ok to not optimize for that case (and delay handle allocation).
This removes a (premature) optimization whis further simplifies
unification.
Change-Id: Ie1259b86ea5e966538667ab9557676e9be9f6364
Reviewed-on: https://go-review.googlesource.com/c/go/+/463989
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Further simplify the unifier by using a mapping from type parameter
to type (argument) handle, where a handle is just an indirection to
the actual type associated with the type parameter.
If multiple type parameters are "joined", i.e., share the same type
(argument), then they use the same handle. Thus, if one of the type
parameters gets a type, all type parameters sharing the same handle
get the same type.
The handles mapping replaces the indices list (mapping from type
parameter index to types index). Because each handle holds any
associated type directly, we also don't need a types list anymore.
We still keep the incoming type parameter list to maintain the same
order for printing and reporting inferred types. We may be able to
eliminate this list as well in future CLs.
Change-Id: I389527dbb325b828c91050e59902ae546c3d0347
Reviewed-on: https://go-review.googlesource.com/c/go/+/463228
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Minor code reorganization: the next version of unify.go doesn't
need this function anymore, so move it where it is still used.
Change-Id: I6744a2361b5dfe2564ec73787a7a110e85ac9f1d
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The unifier was written such that it was possible to specify
a different set of type parameters (declared by different
generic declarations) for each type x, y being unified,
to allow for what is called "bidirectional unification"
in the documentation (comments).
However, in the current implementation, this mechanism is
not used:
- For function type inference, we only consider the
type parameter list of the generic function (type parameters
that appear in the arguments are considered stand-alone types).
We use type parameter renaming to avoid any problems in case
of recursive generic calls that rely on type inference.
- For constraint type inference, the type parameters for the
types x and y (i.e., the type parameter and its constraint)
are the same and had to be explicitly set to be identical.
This CL removes the ability to set separate type parameter
lists. Instead a single type parameter list is used during
unification and is provided when we initialize a unifier.
As a consequence, we don't need to maintain the separate
tparamsList data structure: since we have a single list
of type parameters we can keep it directly in the unifier.
Adjust all the unifier code accordingly and update comments.
As an aside, remove the `exact` flag from the unifier as it
was never set. However, keep the functionality for now and
use a constant (exactUnification) instead. This makes it
easy to find the respectice code without incurring any cost.
Change-Id: I969ba6dbbed2d65d06ba4e20b97bdc362c806772
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Before this CL, the comment used the case of a recursive generic
function call as an example for uni-directional unification.
However, such cases are now more generally (and correctly) addressed
through renaming of the type parameters.
Change-Id: I69e94f53418e1fb4ca9431aeb27c639c40d19b09
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This CL removes the GOEXPERIMENT=nounified knob, and any conditional
statements that depend on that knob. Further CLs to remove unreachable
code follow this one.
Updates #57410.
Change-Id: I39c147e1a83601c73f8316a001705778fee64a91
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Change-Id: I3e9f05d221990b1ae464545d6d8b2e22c35bca21
Reviewed-on: https://go-review.googlesource.com/c/go/+/463077
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Adjust the go/types file generation to run in a test, so that we can
easily reuse the existing logic to verify that the current content of
go/types matches the expected result of generating from types2.
This test will enforce that we don't forget to regenerate go/types when
making changes to types2.
Change-Id: Iee14b1402065f7f0ecbcf28000e07a06c08fa42e
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Apply the following regex substitutions, in order:
golang/go#(\d+) => go.dev/issue/$1
issue #?(\d+) => go.dev/issue/$1
Providing a link uniformly makes it easier to find the respective issue.
Change-Id: I9b60ffa1adb95be181f6711c2f171be3afe2b315
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Some tests in go/types can still not use the typecheck helper functions
because they need a specific fileset for position information.
(We could use a single global file set for all tests to make this work.)
Change-Id: I73552b08a00f08d809c319d3d2328acee9532619
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Add the code to generate initorder.go but do not enable the generation
of that file for now because the generated use uses error_ which has
implications for gopls use (error_ produces a single error instead of
pultiple \t-indented follow-on errors).
Change-Id: I5cd8acdeb8845dbb4716f19cf90d88191dd4216c
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With benchinit, we see a noticeable improvement in init times:
name old time/op new time/op delta
GoTypes 83.4µs ± 0% 43.7µs ± 1% -47.57% (p=0.029 n=4+4)
name old alloc/op new alloc/op delta
GoTypes 26.5kB ± 0% 18.8kB ± 0% -29.15% (p=0.029 n=4+4)
name old allocs/op new allocs/op delta
GoTypes 238 ± 0% 154 ± 0% -35.29% (p=0.029 n=4+4)
Port the same change to cmd/compile/internal/types and types2.
Updates #26775.
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Per benchinit, this makes a big difference to init times:
name old time/op new time/op delta
InternalProfile 185µs ± 1% 6µs ± 1% -96.51% (p=0.008 n=5+5)
name old alloc/op new alloc/op delta
InternalProfile 101kB ± 0% 4kB ± 0% -95.72% (p=0.008 n=5+5)
name old allocs/op new allocs/op delta
InternalProfile 758 ± 0% 25 ± 0% -96.70% (p=0.008 n=5+5)
The fixed 0.2ms init cost is saved for any importer of net/http/pprof,
but also for cmd/compile, as it supports PGO now.
A Go program parsing profiles might not even need to compile these
regular expressions at all, if it doesn't encounter any legacy files.
I suspect this will be the case with most invocations of cmd/compile.
Updates #26775.
Change-Id: I8374dc64459f0b6bb09bbdf9d0b6c55d7ae1646e
Reviewed-on: https://go-review.googlesource.com/c/go/+/460545
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Allow GODEBUG users to report how many times a setting
resulted in non-default behavior.
Record non-default-behaviors for all existing GODEBUGs.
Also rework tests to ensure that runtime is in sync with runtime/metrics.All,
and generate docs mechanically from metrics.All.
For #56986.
Change-Id: Iefa1213e2a5c3f19ea16cd53298c487952ef05a4
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Follow-up on CL 461687 which missed the go/types change.
(As an aside, we cannot yet generate this change because
go/types uses a positioner and types2 just uses a syntax.Pos.)
Change-Id: I28113a2efdc3ddd30cb9a80d2cb2c802ff035ec2
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See also CL 321231 which introduces object.less to match
expected compiler behavior.
Change-Id: I56fbf332a04596dc96393b71d40acf4df5d950fd
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This CL introduces the new files util.go and util_test.go for both
type checkers; these files factor out functionality that is different
between the type checkers so that more code (that is otherwise mostly
the same) can be generated.
With cmpPos/CmpPos factored out, go/types/scope.go can now be generated.
Change-Id: I35f67e53d83b3c5086a559b1e826db83d38ee217
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This will simplify the generation of go/types files from types2 files.
Change-Id: Ie9c8061346cff098cb884908c7eb569267886594
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Starting point for more code sharing.
Change-Id: Ia6bc3ba54476a5202bfd5f89cef09bacb3f4f3b9
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This CL replaces the internal trace flag with Config.trace.
While unexported, it can still be set for testing via reflection.
The typical use is for manual tests, where -v (verbose) turns on
tracing output. Typical use:
go test -run Manual -v
This change makes go/types match types2 behavior.
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go/types:
- gofmt a couple of files
types2:
- add loong64 to sizes list (present in go/types)
- fix a type in validtype.go
- co-locate an accessor with others in typeparam.go
This changes further reduce discrepancy between types2 and go/types.
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This also brings some of the types2 testing code better in sync with
go/types.
Also: fix a minor bug in resolver_test.go (continue traversing
SelectorExpr if the first part is not an identifier).
Change-Id: Ib6c5f6228812b49c185b52a4f02ca5b393418e01
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Also, for go/types, switch to using syntax.Inspect instead of
(deprecated) syntax.Crawl.
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During constraint type inference, unification may fail because it
operates with limited information (core types) even if the actual
type argument satisfies the type constraint in question.
On the other hand, it is safe to ignore failing unification during
constraint type inference because if the failure is true, an error
will be reported when checking instantiation.
Fixes#53650.
Change-Id: Ia76b21ff779bfb1282c1c55f4174847b29cc6f3a
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Use ERROR for substrings, and ERRORx for regexp error patterns.
Correctly unquote patterns for ERROR and ERRORx.
Adjust all tests in internal/types/testdata and locally as needed.
The changes to internal/types/testdata were made through
repeated applications of regexpr find/replace commands
and manual cleanups.
Fixes#51006.
Change-Id: Ib9ec5001243b688bf5aee56b7d4105fb55999ab4
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Before matching the pattern, the double quotes are simply stripped
(no Go string unquoting) for now. This is a first step towards use
of proper Go strings as ERROR patterns.
The changes were obtained through a couple of global regexp
find/replace commands:
/\* ERROR ([^"]+) \*/ => /* ERROR "$1" */
// ERROR ([^"]+)$ => // ERROR "$1"
followed up by manual fixes where multiple "/* ERROR"-style
errors appeared on the same line (in that case, the first
regexp matches the first and last ERROR).
For #51006.
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Sorting is only needed if there are multiple matching errors on
the same line. Instead, in that rare case, select the error that
is closest.
Follow-up on CL 456137.
Change-Id: Ia2056b21c629f3a42495e32de89607fbefb82fa7
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Adjust the testFiles function to use the new commentMap
function. This makes it possible for testFiles to match
the types2.TestFiles logic more closely.
For #51006.
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This adds the (adjusted) syntax.CommentMap function and corresponding
test to the types_test package so that we can use it for collecting
ERROR comments in the next CL.
For #51006.
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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
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While at it, also remove the word "constraint" in the detail explanation
of an unsatisfied constraint.
Fixes#57500.
Change-Id: I55dae1694de2cfdb434aeba9d4a3530af7aca8f5
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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
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Fixes#57486.
Change-Id: I4b71199a724718886ce6d7a49e96a9ebdcbcf737
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Rather than reporting an impossible conversion error when mixing an
untyped value with a pointer type in an operation, report a type
mismatch error. This fixes a regression in error quality compared
to pre-1.18.
For the fix, clean up the implementation of canMix, add documentation,
and give it a better name.
Adjust test case for corresponding error code bacause we now get a
better error message (and error code) for the old error code example.
Fixes#57160.
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Reviewed-by: Robert Griesemer <gri@google.com>
Type inference uses a trick of "renaming" type parameters in the type
parameter list to avoid cycles during unification. This separates the
identity of type parameters from type arguments. When this trick was
introduced in CL 385494, we restricted its application to scenarios
where inference is truly self-recursive: the type parameter list being
inferred was the same as the type parameter list of the outer function
declaration. Unfortunately, the heuristic used to determine
self-recursiveness was flawed: type-checking function literals clobbers
the type-checker environment, losing information about the outer
signature.
We could fix this by introducing yet more state into the type-checker
(e.g. a 'declSig' field that would hold the signature of the active
function declaration), but it is simpler to just avoid this optimization
and always perform type parameter renaming. We can always optimize
later.
This CL removes the check for true self-recursion, always performing the
renaming.
Fixesgolang/go#57155
Change-Id: I34c7617005c1f0ccfe2192da0e5ed104be6b92c9
Reviewed-on: https://go-review.googlesource.com/c/go/+/456236
Run-TryBot: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Robert Griesemer
Matthew Dempsky
cui fliter
Cuong Manh Le
Robert Findley
Daniel Martí
Russ Cox