Change-Id: I28a1910890659aaa449ffd2a847cd4ced5a8600d
Reviewed-on: https://go-review.googlesource.com/c/go/+/310211
Trust: Keith Randall <khr@golang.org>
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Add in some missing global assignment ops to the list of globals ops
that should be traversed to look for generic function instantiations.
The most common other one for global assigments (and the relevant one
for this bug) is OAS2FUNC, but also look at global assigments with
OAS2DOTTYPE, OAS2MAPR, OAS2RECV, and OASOP.
Bonus small fix: get rid of -G=3 case in ir.IsAddressable. Now that we
don't call the old typechecker from noder2, we don't need this -G-3
check anymore.
Fixes#45547.
Change-Id: I75fecec55ea0d6f62e1c2294d4d77447ed9be6ae
Reviewed-on: https://go-review.googlesource.com/c/go/+/310210
Trust: Dan Scales <danscales@google.com>
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During substitution of the function type during stenciling, we must set
the Name nodes of the param/result fields of the func type. We get those
name nodes from the substituted Dcl nodes of the PPARAMS and PPARAMOUTs.
But we must check that the names match with the Dcl nodes, so that we
skip any param fields that correspond to unnamed (in) parameters.
Added a few tests to typelist.go by removing a variety of unneeded
function parameter names.
Change-Id: If786961b64549da6f18eeeb5060ea58fab874eb9
Reviewed-on: https://go-review.googlesource.com/c/go/+/305912
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Handle the case where types can be partially inferred for an
instantiated function that is not immediately called. The key for the
Inferred map is the CallExpr (if inferring types required the function
arguments) or the IndexExpr (if types could be inferred without the
function arguments).
Added new tests for the case where the function isn't immediately called
to typelist.go.
Change-Id: I60f503ad67cd192da2f2002060229efd4930dc39
Reviewed-on: https://go-review.googlesource.com/c/go/+/305909
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The correct setting of t.nod is needed when exporting types. Make sure
we create instantiated named types correctly so t.nod is set.
New test file interfacearg.go that tests this (by instantiating a type
with an interface). Also has tests for various kinds of method
expressions.
Change-Id: Ia7fd9debd495336b73788af9e35d72331bb7d2b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/305730
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Fix various small bugs related to delaying transformations due to type
params. Most of these relate to the need to delay a transformation when
an argument of an expression or statement has a type parameter that has
a structural constraint. The structural constraint implies the operation
should work, but the transformation can't happen until the actual value
of the type parameter is known.
- delay transformations for send statements and return statements if
any args/values have type params.
- similarly, delay transformation of a call where the function arg has
type parameters. This is mainly important for the case where the
function arg is a pure type parameter, but has a structural
constraint that requires it to be a function. Move the setting of
n.Use to transformCall(), since we may not know how many return
values there are until then, if the function arg is a type parameter.
- set the type of unary expressions from the type2 type (as we do with
most other expressions), since that works better with expressions
with type params.
- deal with these delayed transformations in subster.node() and convert
the CALL checks to a switch statement.
- make sure ir.CurFunc is set properly during stenciling, including
closures (needed for transforming return statements during
stenciling).
New test file typelist.go with tests for these cases.
Change-Id: I1b82f949d8cec47d906429209e846f4ebc8ec85e
Reviewed-on: https://go-review.googlesource.com/c/go/+/305729
Trust: Dan Scales <danscales@google.com>
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For additions, compares, and slices, create transform functions that do
just the transformations for those nodes by the typecheck package (given
that the code has been fully typechecked by types2). For nodes that have
no args with typeparams, we call these transform functions directly in
noder2. But for nodes that have args with typeparams, we have to delay
and call the tranform functions during stenciling, since we don't know
the specific types involved.
We indicate that a node still needs transformation by setting Typecheck
to a new value 3. This value means the current type of the node has been
set (via types2), but the node may still need transformation.
Had to export typcheck.IsCmp and typecheck.Assignop from the typecheck
package.
Added new tests list2.go (required delaying compare typecheck/transform
because of != compare in checkList) and adder.go (requires delaying add
typecheck/transform, since it can do addition for numbers or strings).
There are several more transformation functions needed for expressions
(indexing, calls, etc.) and several more complicated ones needed for
statements (mainly various kinds of assignments).
Change-Id: I7d89d13a4108308ea0304a4b815ab60b40c59b0a
Reviewed-on: https://go-review.googlesource.com/c/go/+/303091
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types2 will give us a constant with a type T, if an untyped constant is
used with another operand of type T (in a provably correct way). When we
substitute in the type args during stenciling, we now know the real type
of the constant. We may then need to change the BasicLit.val to be the
correct type (e.g. convert an int64Val constant to a floatVal constant).
Otherwise, later parts of the compiler will be confused.
Updated tests list.go and double.go with uses of untyped constants.
Change-Id: I9966bbb0dea3a7de1c5a6420f8ad8af9ca84a33e
Reviewed-on: https://go-review.googlesource.com/c/go/+/303089
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For Builtin ops, we currently stay with using the old
typechecker to transform the call to a more specific expression
and possibly use more specific ops. However, for a bunch of the
ops, we delay calling the old typechecker if any of the args have
type params, for a variety of reasons.
In the near future, we will start creating separate functions that do
the same transformations as the old typechecker for calls, builtins,
indexing, comparisons, etc. These functions can then be called at noder
time for nodes with no type params, and at stenciling time for nodes
with type params.
Remove unnecessary calls to types1 typechecker for most kinds of
statements (still need it for SendStmt, AssignStmt, ReturnStmt, and
SelectStmt). In particular, we don't need it for RangeStmt, and this
avoids some complaints by the types1 typechecker on generic code.
Other small changes:
- Fix check on whether to delay calling types1-typechecker on type
conversions. Should check if HasTParam is true, rather than if the
type is directly a TYPEPARAM.
- Don't call types1-typechecker on an indexing operation if the left
operand has a typeparam in its type and is not obviously a TMAP,
TSLICE, or TARRAY. As above, we will eventually have to create a new
function that can do the required transformations (for complicated
cases) at noder time or stenciling time.
- Copy n.BuiltinOp in subster.node()
- The complex arithmetic example in absdiff.go now works.
- Added new tests double.go and append.go
- Added new example with a new() call in settable.go
Change-Id: I8f377afb6126cab1826bd3c2732aa8cdf1f7e0b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/301951
Run-TryBot: Dan Scales <danscales@google.com>
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Ignore an embedded type in an interface which is the predeclared
interface "comparable" (which currently can only be in a type
constraint), since the name doesn't resolve and the "comparable" type
doesn't have any relevant methods (for the purposes of the compiler).
Added new test case graph.go that needs this fix.
Change-Id: I2443d2c3dfeb9d0a78aaaaf91a2808ae2759d247
Reviewed-on: https://go-review.googlesource.com/c/go/+/301831
Trust: Dan Scales <danscales@google.com>
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Added test example orderedmap.go (binary search tree) that requires this
fix (calling function compare in _Map).
Also added new tests slices.go and metrics.go that just work.
Change-Id: Ifa5f42ab6eee9aa54c40f0eca19e00a87f8f608a
Reviewed-on: https://go-review.googlesource.com/c/go/+/301829
Trust: Dan Scales <danscales@google.com>
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Add support for maps in subster.typ(). Add new test cases maps.go and set.go.
Change substitution of a TFUNC in subster.typ() to always create new
param and result structs if any of the receiver, param, or result
structs get substituted. All these func structs must be copied, because
they have offset fields that are dependent, and so must have an
independent copy for each new signature (else there will be an error
later when frame offsets are calculated).
Change-Id: I576942a62f06b46b6f005abc98f65533008de8dc
Reviewed-on: https://go-review.googlesource.com/c/go/+/301670
Trust: Dan Scales <danscales@google.com>
Trust: Robert Griesemer <gri@golang.org>
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Add support for channels in subster.typ(). Add new test file chans.go.
To support assignability of bidirectional channel args to directional
channel params, I needed to type check generic calls after they are
instantiated. (Eventually, we will create separate functions to just do
the assignability logic, so we don't need to call the old typechecker in
this case.) So, for generic calls, we now leave the call as OCALL (as a
signal that the call still needs typechecking), and do typecheck.Call()
during stenciling.
Smaller changes:
- Set the type of an instantiated OCLOSURE node (and not just the associated
OFUNC node)
- In instTypeName2, filter out the space that types2.TypeString inserts
after a common in a typelist. Our standard naming requires no space
after the comma.
- With the assignability fix above, I no longer need the explicit
conversions in cons.go.
Change-Id: I148858bfc6708c0aa3f50bad7debce2b8c8c091f
Reviewed-on: https://go-review.googlesource.com/c/go/+/301669
Trust: Dan Scales <danscales@google.com>
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Simple change to avoid calling the old typechecker in noder.Addr(). This
fixes cases where generic code calls a pointer method with a non-pointer
receiver.
Added test typeparam/lockable.go that now works with this change.
For lockable.go to work, also fix incorrect check to decide whether to
translate an OXDOT now or later. We should delay translating an OXDOT
until instantiation (because we don't know how embedding, etc. will
work) if the receiver has any typeparam, not just if the receiver type
is a simple typeparam. We also have to handle OXDOT for now in
IsAddressable(), until we can remove calls to the old typechecker in
(*irgen).funcBody().
Change-Id: I77ee5efcef9a8f6c7133564106a32437e36ba4bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/300990
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In the case of partially inferred type arguments, we need to use the
IndexExpr as the key in g.info.Inferred[] rather than the CallExpr.
Added an extra fromStrings1 call in the settable.go test that tests
partially inferred type arguments. This new call uses a new concrete
type SettableString as well.
I also added another implementation fromStrings3 (derived from a go2go
tests) that typechecks but intentionally causes a panic.
Change-Id: I74d35c5a741f72f37160a96fbec939451157f392
Reviewed-on: https://go-review.googlesource.com/c/go/+/300309
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Deal with cases like: 'type P[T any] T' (used to add methods to an
arbitrary type T), In this case, P[T] has kind types.TTYPEPARAM (as does
T itself), but requires more code to substitute than a simple TTYPEPARAM
T. See the comment near the beginning of subster.typ() in stencil.go.
Add new test absdiff.go. This test has a case for complex types (which
I've commented out) that will only work when we deal better with Go
builtins in generic functions (like real and imag).
Remove change in fmt.go for TTYPEPARAMS that is no longer needed (since
all TTYPEPARAMS have a sym) and was sometimes causing an extra prefix
when formatting method names.
Separate out the setting of a TTYPEPARAM bound, since it can reference
the TTYPEPARAM being defined, so must be done separately. Also, we don't
currently (and may not ever) need bounds after types2 typechecking.
Change-Id: Id173057e0c4563b309b95e665e9c1151ead4ba77
Reviewed-on: https://go-review.googlesource.com/c/go/+/300049
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Get instantiatiated generic types working with interfaces, including
typechecking assignments to interfaces and instantiating all the methods
properly. To get it all working, this change includes:
- Add support for substituting in interfaces in subster.typ()
- Fill in the info for the methods for all instantiated generic types,
so those methods will be available for later typechecking (by the old
typechecker) when assigning an instantiated generic type to an
interface. We also want those methods available so we have the list
when we want to instantiate all methods of an instantiated type. We
have both for instantiated types encountered during the initial noder
phase, and for instantiated types created during stenciling of a
function/method.
- When we first create a fully-instantiated generic type (whether
during initial noder2 pass or while instantiating a method/function),
add it to a list so that all of its methods will also be
instantiated. This is needed so that an instantiated type can be
assigned to an interface.
- Properly substitute type names in the names of instantiated methods.
- New accessor methods for types.Type.RParam.
- To deal with generic types which are empty structs (or just don't use
their type params anywhere), we want to set HasTParam if a named type
has any type params that are not fully instantiated, even if the
type param is not used in the type.
- In subst.typ() and elsewhere, always set sym.Def for a new forwarding
type we are creating, so we always create a single unique type for
each generic type instantiation. This handles recursion within a
type, and also recursive relationships across many types or methods.
We remove the seen[] hashtable, which was serving the same purpose,
but for subst.typ() only. We now handle all kinds of recursive types.
- We don't seem to need to force types.CheckSize() on
created/substituted generic types anymore, so commented out for now.
- Add an RParams accessor to types2.Signature, and also a new
exported types2.AsSignature() function.
Change-Id: If6c5dd98427b20bfe9de3379cc16f83df9c9b632
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- Deal with closures in generic functions by fixing the stenciling code
- Deal with instantiated function values (instantiated generic
functions that are not immediately called) during stenciling. This
requires changing the OFUNCINST node to an ONAME node for the
appropriately instantiated function. We do this in a second pass,
since this is uncommon, but requires editing the tree at multiple
levels.
- Check global assignments (as well as functions) for generic function
instantiations.
- Fix a bug in (*subst).typ where a generic type in a generic function
may definitely not use all the type args of the function, so we need
to translate the rparams of the type based on the tparams/targs of
the function.
- Added new test combine.go that tests out closures in generic
functions and instantiated function values.
- Added one new variant to the settable test.
- Enabling inlining functions with closures for -G=3. (For now, set
Ntype on closures in -G=3 mode to keep compatibility with later parts
of compiler, and allow inlining of functions with closures.)
Change-Id: Iea63d5704c322e42e2f750a83adc8b44f911d4ec
Reviewed-on: https://go-review.googlesource.com/c/go/+/296269
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A type may now have a type param in it, either because it has been
composed from a function type param, or it has been declared as or
derived from a reference to a generic type. No objects or types with
type params can be exported yet. No generic type has a runtime
descriptor (but will likely eventually be associated with a dictionary).
types.Type now has an RParam field, which for a Named type can specify
the type params (in order) that must be supplied to fully instantiate
the type. Also, there is a new flag HasTParam to indicate if there is
a type param (TTYPEPARAM) anywhere in the type.
An instantiated generic type (whether fully instantiated or
re-instantiated to new type params) is a defined type, even though there
was no explicit declaration. This allows us to handle recursive
instantiated types (and improves printing of types).
To avoid the need to transform later in the compiler, an instantiation
of a method of a generic type is immediately represented as a function
with the method as the first argument.
Added 5 tests on generic types to test/typeparams, including list.go,
which tests recursive generic types.
Change-Id: Ib7ff27abd369a06d1c8ea84edc6ca1fd74bbb7c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/292652
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- Create the stencil name using targ.Type.String(), which handles cases
where, for example, a type argument is a pointer to a named type,
etc. *obj.
- Set name.Def properly for a new stenciled func (have the symbol point
back to the associated function node). Will be required when exporting.
- Add missing copying of Func field when making copies of Name nodes.
(On purpose (it seems), Name nodes don't have a copy() function, so
we have to copy all the needed fields explicitly.)
- Deal with nil type in subster.node(), which is the type of the return
value for a function that doesn't return anything.
- Fix min to match standard want/go form, and add in float tests. Changed
Got -> got in bunch of other typeparam tests.
- Add new tests index.go, settable.go, and smallest.go (similar to
examples in the type param proposal), some of which need the above
changes.
Change-Id: I09a72302bc1fd3635a326da92405222afa222e85
Reviewed-on: https://go-review.googlesource.com/c/go/+/291109
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When doing a type conversion using a type param, delay the
transformation to OCONV/OCONVNOP until stenciling, since the nodes
created depend on the actual type.
Re-enable the fact.go test.
Change-Id: I3d5861aab3dd0e781d767f67435afaf951dfe451
Reviewed-on: https://go-review.googlesource.com/c/go/+/290752
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- Have to delay the extra transformation on methods invoked on a type
param, since the actual transformation (including path through
embedded fields) will depend on the instantiated type. I am currently
doing the transformation during the stencil substitution phase. We
probably should have a separate pass after noder2 and stenciling,
which drives the extra transformations that were in the old
typechecker.
- We handle method values (that are not called) and method calls. We
don't currently handle method expressions.
- Handle type substitution in function types, which is needed for
function args in generic functions.
- Added stringer.go and map.go tests, testing the above changes
(including constraints with embedded interfaces).
Change-Id: I3831a937d2b8814150f75bebf9f23ab10b93fa00
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Disabled test/typeparam/fact.go for now as there's an issue
with stenciling.
Change-Id: Ie328a217de6d7b6695737f08ef5c944bcdaabd39
Reviewed-on: https://go-review.googlesource.com/c/go/+/290471
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- Handle generic function calling itself or another generic function in
stenciling. This is easy - after it is created, just scan an
instantiated generic function for function instantiations (that may
needed to be stenciled), just like non-generic functions. The types
in the function instantiation will already have been set by the
stenciling.
- Handle OTYPE nodes in subster.node() (allows for generic type
conversions).
- Eliminated some duplicated work in subster.typ().
- Added new test case fact.go that tests a generic function calling
itself, and simple generic type conversions.
- Cause an error if a generic function is to be exported (which we
don't handle yet).
- Fixed some suggested changes in the add.go test case that I missed in
the last review.
Change-Id: I5d61704254c27962f358d5a3d2e0c62a5099f148
Reviewed-on: https://go-review.googlesource.com/c/go/+/290469
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Allow full compilation and running of simple programs with generic
functions by stenciling on the fly the needed generic functions. Deal
with some simple derived types based on type params.
Include a few new typeparam tests min.go and add.go which involve
fully compiling and running simple generic code.
Change-Id: Ifc2a64ecacdbd860faaeee800e2ef49ffef9df5e
Reviewed-on: https://go-review.googlesource.com/c/go/+/289630
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Change-Id: Ie2950cdc5406915935f114bfd97ef03d965f9069
Reviewed-on: https://go-review.googlesource.com/c/go/+/274616
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Change-Id: I9044de7829d22addb5bc570401508082e3f007eb
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
This change makes a first connection between the compiler and types2.
When the -G flag is provided, the compiler accepts code using type
parameters; with this change generic code is also type-checked (but
then compilation ends).
Change-Id: I0fa6f6213267a458a6b33afe8ff26869fd838a63
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Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Providing the -G flag instructs the compiler to accept type parameters.
For now, the compiler only parses such files and then exits.
Added a new test directory (test/typeparam) and initial test case.
Port from dev.go2go branch.
Change-Id: Ic11e33a9d5f012f8def0bdae205043659562ac73
Reviewed-on: https://go-review.googlesource.com/c/go/+/261660
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
