This CL updates unified IR to look at the structural type of a
composite literal type, rather than merely the underlying type, to
determine if it's a structure. This fixes a number of currently
failing regress test cases.
Updates #50833.
Change-Id: I11c040c77ec86c23e8ffefcf1ce1aed548687dc5
Reviewed-on: https://go-review.googlesource.com/c/go/+/381074
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When exporting the "any" empty interface type for unified IR, write it
out as a reference to the "any" alias, rather than to the underlying
empty interface. This matches how "byte" and "rune" are handled.
Verified to fix the issue demonstrated in CL 369975.
Change-Id: Ic2844b0acc3b17c20b3a40aaf262f62ec653eb5a
Reviewed-on: https://go-review.googlesource.com/c/go/+/370374
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This is a port of CL 352616 from go/types to types2. It also removes
Interface.IsConstraint and adjusts all uses to use IsMethodSet. The
dual changes are made to the (unexported) type set implementation.
Change-Id: I292b741d1f7cdbaefb483eed75faf7b85a8d2792
Reviewed-on: https://go-review.googlesource.com/c/go/+/352872
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This is a port of CL 349629 from go/types to types2, adjusted to
make it work for types2. It also includes the necessary compiler
changes, provided by mdempsky.
Change-Id: If8de174cee9c69df0d0642fcec1ee7622b7c3852
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This is a slightly adjusted port of CL 350996 from go/types to types2.
Change-Id: I8f5902ecb20a4b4d2a5ef0d3641d857bc3a618e2
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To be consistent with CL 348376, spell out 'RecvTypeParams' in go/types
and types2 API.
Updates #47916
Change-Id: If8b3fd4274ccb944bd0ff04d7007e94e5fba61c1
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This is a vestigial artifact of how I initially split apart the public
and private data for objects. But now objects are split into more
parts, and it's proven easier to just keep them as separate variables.
So it's time to cleanup the initial public/private code to follow the
same approach.
Change-Id: I3976b19fb433cbe21d299d3799ec616f9e59561e
Reviewed-on: https://go-review.googlesource.com/c/go/+/348412
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In indexed export, values are always exported along with their type
and are encoded in a type-sensitive manner, because this matches how
cmd/compile handled constants internally.
However, go/types intentionally differs from this, decoupling type
from value representation. As unified IR strives to be more
go/types-centric, it makes sense to embrace this and make values a
more first-class encoding.
Change-Id: If21d849c4f610358bd776d5665469d180bcd5f6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/348014
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This is a port of CL 348376 with the necessary adjustments
in the compiler.
Change-Id: Ib11ee841b194746ff231ee493aa56bf9b3a4a67f
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This is a port of CL 343934 from go/types with the necessary
adjustments to the compiler.
Change-Id: I810144e6e2eb2bc8fa0d34dc206403c993cbbe7a
Reviewed-on: https://go-review.googlesource.com/c/go/+/344616
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This is a port of CL 343933 from go/types with the necessary
adjustments in the compiler.
With this CL type parameters and type lists are now held in
TParamList and TypeList data types which don't expose the
internal representation.
Change-Id: I6d60881b5db995dbc04ed3f4a96e8b5d41f83969
Reviewed-on: https://go-review.googlesource.com/c/go/+/344615
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This is a port of CL 343932 from go/types, with the necessary adjustments
to the compiler.
This change improves type safety slightly, avoids many internal type
assertions, and simplifies some code paths.
Change-Id: Ie9c4734814f49cd248927152d7b3264d3578428c
Reviewed-on: https://go-review.googlesource.com/c/go/+/344614
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With types2, some syntax.PosBases need to be constructed from export
data, which must only contain "trimmed" filenames (i.e., that they've
already been made absolute and undergone -trimpath processing).
However, it's not safe to apply trimming to a filename multiple times,
and in general we can't distinguish trimmed from untrimmed filenames.
This CL resolves this by adding a PosBase.Trimmed boolean so we can
distinguish whether the associated filename has been trimmed yet. This
is a bit hacky, but is the least bad solution I've come up with so
far.
This unblocks enabling -G=3 by default.
Change-Id: I7383becfb704680a36f7603e3246af38b21f100b
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The 'TypeParams' name is too easily confused with the singular
'TypeParam', and does not say anything about what type of collection it
is. We decided that TTuple was not great. TParamList seems OK for now,
though perhaps a better name will emerge.
Change-Id: I5eabdc91b1f666bb4c7ea8acdbebf7c372d19227
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Export a term as a pair (tilde, type) rather than (type, tilde)
to match the new Union/Term API.
Change-Id: I221c09c2c746ae19fbae0c970ffb26fa7a8ac736
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Instead of providing a list of tildes and types, use a list of
Terms to create a Union, with suitable accessors.
Define the (exported) notion of a Term representing a union term.
This simplified various uses and also will be easier to extend
should we want to add more information to a Term in the future.
Change-Id: I52fd73938bfa11bac60adbf10580b6d0680df4f1
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In unified IR, fail right away if we find a types2.Invalid while
writing out the package. This provides a clearer error message for
https://github.com/golang/go/issues/25838#issuecomment-448746670.
Updates #25838.
Change-Id: I6902fdd891fc31bbb832b6fdba00eca301282409
Reviewed-on: https://go-review.googlesource.com/c/go/+/338973
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Change-Id: Id68d41f09e78343953167cb1e38fb1ebc41a34d4
Reviewed-on: https://go-review.googlesource.com/c/go/+/338429
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This is a port of CL 336249 with adjustments due to slightly
different handling of type parameter declaration in types2.
The CL also contains adjustments to the compiler front-end.
With this change it is not necessary to export type parameter
indices. Filed issue #47451 so we don't forget.
Change-Id: I2834f7be313fcb4763dff2a9058f1983ee6a81b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/338192
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After the previous two CLs, there's no need for unified IR to
write/read blank functions anymore: types2 has already checked that
they're valid, and the compiler backend is going to ignore them.
Allows dropping code for worrying about blank methods and will
probably simplify some of the object handling code eventually too.
Fixes#47446.
Change-Id: I03cb722793d676a246b1ab768b5cf0d3d2578b12
Reviewed-on: https://go-review.googlesource.com/c/go/+/338096
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This CL makes two changes:
1. It moves object symbols and code tags into a new "relocName"
relocation, which should eventually allow getting rid of objStub.
2. It moves the type parameter data into the relocObjDict relocation,
so everything related to writing out dictionaries is contained there.
Change-Id: If0f7ff7d9384e8664957c3180bf6f20e97bcff6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/336051
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Records whether a derived type is needed at run-time as well as
instantiated functions that rely on derived types (and thus need
sub-dictionaries).
Change-Id: I2f2036976bfce5b3b4372fba88b4116dafa7e6b7
Reviewed-on: https://go-review.googlesource.com/c/go/+/334349
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This CL pushes the typecheck.Expr calls further down to the IR
construction points. It turns out we don't really care about
typecheck.AssignExpr, because it's only used to distinguish whether
ir.BlankNode is allowed. We can avoid that issue by just skipping the
call to typecheck.Expr for blank nodes.
Similarly, for typecheck.Callee, only two details matter: (1) don't
report errors for builtin functions (which aren't allowed outside of
callee contexts); and (2) method-value selector expressions need to
have Op ODOTMETH/ODOTINTER rather than OMETHVALUE. The first can be
handled by simply skipping typecheck on Names (as with ir.BlankNode,
we don't need to typecheck these). The second currently requires
adding a 'callee bool' parameter to disambiguate the context.
The other option would be for exprCall to reset the fun's Op from
OMETHVALUE to OXDOT and let typecheck handle it a second time. But I
anticipate needing to add extra logic in the exprSelector case which
would be harder to undo, so this seems somewhat better.
Change-Id: I1a8dfb6af04265ab466fd7f4cb6ee8b479e92282
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CL 332469 changed the unified IR reader to incrementally typecheck
each statement as they're read/constructed. This CL goes further to
incrementally typecheck each expression.
While here, this CL reorganizes a few things to make this go more
smoothly. In particular, it renames expr to expr0 and adds a new expr
wrapper that applies typecheck.Expr; gets rid of exprTypeSwitchguard
by moving that logic into switchStmt; and splits exprConvert out from
exprCall, which simplifies the logic for typechecking the calleee
expression somewhat.
Change-Id: I6289de9388dc94a947971f4b7213aafeb2faa5dc
Reviewed-on: https://go-review.googlesource.com/c/go/+/333730
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This CL updates the unified IR export data serialization to explicitly
and separately record the derived types used by a declaration. The
readers currently just use this data to construct types/IR the same as
before, but eventually we can use it for emitting GC-shape
dictionaries.
Change-Id: I7d67ad9b3f1fbe69664bf19e056bc94f73507220
Reviewed-on: https://go-review.googlesource.com/c/go/+/331829
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While initially building out unified IR, I didn't have any indexing
scheme. Everything was written out in order. Consequently, if I wanted
to write A before B, I had to compute A before B.
One particular example of this is handling closure variables: the
reader needs the list of closure variables before it can start reading
the function body, so I had to write them out first, and so I had to
compute them first in a separate, dedicated pass.
However, that constraint went away a while ago. For example, it's now
possible to replace the two-pass closure variable capture with a
single pass. We just write out the function body earlier, but then
wait to write out its index.
I anticipate this approach will make it easier to implement
dictionaries: rather than needing a separate pass to correctly
recognize and handle all of the generics cases, we can just hook into
the existing logic.
Change-Id: Iab1e07f9202cd5d2b6864eef10116960456214df
Reviewed-on: https://go-review.googlesource.com/c/go/+/330851
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We need to start the capture walk from expr.Body, not expr, otherwise
in quirks mode we'll set all of the captured variables' positions to
expr.Body.Rbrace.
Change-Id: Ic93f2773ae3756c2ec88dac17b4e9fb5a0771734
Reviewed-on: https://go-review.googlesource.com/c/go/+/330889
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This CL refactors CaptureVars to use a visitor type so it's easier to
break out helper functions to review.
It also simplifies the quirks-mode handling of function literals:
instead of trying to maintain information about whether we're inside a
function literal or not, it now just rewrites the recorded position
information for any newly added free variables after walking the
function literal.
(Quirks mode is only for "toolstash -cmp"-style binary output testing
of normal code and will eventually be removed, so I don't think it's
important that this is an O(N^2) algorithm for deeply nested function
literals with lots of free variables.)
Change-Id: I0689984f6d88cf9937d4706d2d8de96415eaeee3
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The previous code for walking the syntax AST to find declarations
needed to know whether a declaration appeared within block scope, but
syntax.Crawl (née syntax.Walk) made that somewhat awkward.
This CL simplifies it a little, taking advantage of syntax.Walk's
support for keeping per-subtree state.
Change-Id: I03c7da8c44bec40f88e983852dc6bbab7e6ac13c
Reviewed-on: https://go-review.googlesource.com/c/go/+/330549
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This CL adds go/ast's Visitor, Walk, and Inspect functions to package
syntax. Having functions with the same API and semantics as their
go/ast counterparts reduces the mental load of context switching
between go/ast and syntax.
It also renames the existing Walk function into Crawl, and marks it as
a deprecated wrapper around Inspect. (I named it "Crawl" because it's
less functional than "Walk"... get it??)
There aren't that many callers to Crawl, so we can probably remove it
in the future. But it doesn't seem pressing, and I'm more concerned
about the risk of forgetting to invert a bool condition somewhere.
Change-Id: Ib2fb275873a1d1a730249c9cb584864cb6ec370e
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This CL extends the unified export data format's existing sync
mechanism to save writer stacks, controlled by the -d=syncframes debug
flag. This allows readers to provide more details when reporting
desync errors, which should simplify development of the data format
and the various reader/writer implementations.
For example, CL 328051 updated reader and writer, but missed making a
similar change to the linker (fix in CL 328054). Re-reviewing the CL
in isolation after the failure, it was not immediately obvious what
was going wrong. But the pair of stack traces below identifies exactly
what happened: it should have updated linker.relocFuncExt to write out
the new sync marker too.
```
data sync error: package "internal/abi", section 6, index 4, offset 536
found UseReloc, written at:
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/encoder.go:221: (*encoder).reloc +0x44
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/linker.go:214: (*linker).relocFuncExt +0x580
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/linker.go:233: (*linker).relocTypeExt +0x234
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/linker.go:161: (*linker).relocObj +0x2198
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/linker.go:64: (*linker).relocIdx +0x196
expected ImplicitTypes, reading at:
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/reader.go:796: (*reader).implicitTypes +0x36
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/reader.go:810: (*reader).addBody +0x81
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/reader.go:727: (*reader).funcExt +0x542
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/reader.go:651: (*reader).method +0x324
/home/mdempsky/wd/go/src/cmd/compile/internal/noder/reader.go:557: (*pkgReader).objIdx +0x2704
```
Change-Id: I911193edd2a965f81b7459f15fb613a773584685
Reviewed-on: https://go-review.googlesource.com/c/go/+/328909
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The logic for handling them must keep in sync between reader/writer, so
factoring them out from addBody make it's easier to refer later.
Change-Id: I26447065867d79f4f47cc678a398b9e7bf5d2403
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This CL adds a new unified IR construction mode to the frontend. It's
purely additive, and all files include "UNREVIEWED" at the top, like
how types2 was initially imported. The next CL adds a -d=unified flag
to actually enable unified IR mode.
See below for more details, but some highlights:
1. It adds ~6kloc (excluding enum listings and stringer output), but I
estimate it will allow removing ~14kloc (see CL 324670, including its
commit message);
2. When enabled by default, it passes more tests than -G=3 does (see
CL 325213 and CL 324673);
3. Without requiring any new code, it supports inlining of more code
than the current inliner (see CL 324574; contrast CL 283112 and CL
266203, which added support for inlining function literals and type
switches, respectively);
4. Aside from dictionaries (which I intend to add still), its support
for generics is more complete (e.g., it fully supports local types,
including local generic types within generic functions and
instantiating generic types with local types; see
test/typeparam/nested.go);
5. It supports lazy loading of types and objects for types2 type
checking;
6. It supports re-exporting of types, objects, and inline bodies
without needing to parse them into IR;
7. The new export data format has extensive support for debugging with
"sync" markers, so mistakes during development are easier to catch;
8. When compiling with -d=inlfuncswithclosures=0, it enables "quirks
mode" where it generates output that passes toolstash -cmp.
--
The new unified IR pipeline combines noding, stenciling, inlining, and
import/export into a single, shared code path. Previously, IR trees
went through multiple phases of copying during compilation:
1. "Noding": the syntax AST is copied into the initial IR form. To
support generics, there's now also "irgen", which implements the same
idea, but takes advantage of types2 type-checking results to more
directly construct IR.
2. "Stenciling": generic IR forms are copied into instantiated IR
forms, substituting type parameters as appropriate.
3. "Inlining": the inliner made backup copies of inlinable functions,
and then copied them again when inlining into a call site, with some
modifications (e.g., updating position information, rewriting variable
references, changing "return" statements into "goto").
4. "Importing/exporting": the exporter wrote out the IR as saved by
the inliner, and then the importer read it back as to be used by the
inliner again. Normal functions are imported/exported "desugared",
while generic functions are imported/exported in source form.
These passes are all conceptually the same thing: make a copy of a
function body, maybe with some minor changes/substitutions. However,
they're all completely separate implementations that frequently run
into the same issues because IR has many nuanced corner cases.
For example, inlining currently doesn't support local defined types,
"range" loops, or labeled "for"/"switch" statements, because these
require special handling around Sym references. We've recently
extended the inliner to support new features like inlining type
switches and function literals, and they've had issues. The exporter
only knows how to export from IR form, so when re-exporting inlinable
functions (e.g., methods on imported types that are exposed via
exported APIs), these functions may need to be imported as IR for the
sole purpose of being immediately exported back out again.
By unifying all of these modes of copying into a single code path that
cleanly separates concerns, we eliminate many of these possible
issues. Some recent examples:
1. Issues #45743 and #46472 were issues where type switches were
mishandled by inlining and stenciling, respectively; but neither of
these affected unified IR, because it constructs type switches using
the exact same code as for normal functions.
2. CL 325409 fixes an issue in stenciling with implicit conversion of
values of type-parameter type to variables of interface type, but this
issue did not affect unified IR.
Change-Id: I5a05991fe16d68bb0f712503e034cb9f2d19e296
Reviewed-on: https://go-review.googlesource.com/c/go/+/324573
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
