mirror of
https://github.com/golang/go
synced 2024-11-11 23:10:23 -07:00
[dev.typeparams] cmd/compile: allow types with the same underlying type to have the same shape
First baby step to sharing the underlying implementation among several types. Change-Id: I6a156176d2b7f0131a87285a03b881ce380c26ed Reviewed-on: https://go-review.googlesource.com/c/go/+/338610 Trust: Keith Randall <khr@golang.org> Trust: Dan Scales <danscales@google.com> Run-TryBot: Keith Randall <khr@golang.org> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Dan Scales <danscales@google.com>
This commit is contained in:
parent
fd0011dca5
commit
40e561d933
@ -1920,7 +1920,7 @@ func methodWrapper(rcvr *types.Type, method *types.Field, forItab bool) *obj.LSy
|
||||
// Target method uses shaped names.
|
||||
targs2 := make([]*types.Type, len(targs))
|
||||
for i, t := range targs {
|
||||
targs2[i] = typecheck.Shaped[t]
|
||||
targs2[i] = typecheck.Shapify(t)
|
||||
}
|
||||
targs = targs2
|
||||
|
||||
|
@ -1348,32 +1348,26 @@ func Shapify(t *types.Type) *types.Type {
|
||||
if t.IsShape() {
|
||||
return t // TODO: is this right?
|
||||
}
|
||||
if s := Shaped[t]; s != nil {
|
||||
// Map all types with the same underlying type to the same shape.
|
||||
u := t.Underlying()
|
||||
|
||||
if s := shaped[u]; s != nil {
|
||||
return s //TODO: keep?
|
||||
}
|
||||
|
||||
// For now, there is a 1-1 mapping between regular types and shape types.
|
||||
sym := Lookup(fmt.Sprintf(".shape%d", snum))
|
||||
snum++
|
||||
name := ir.NewDeclNameAt(t.Pos(), ir.OTYPE, sym)
|
||||
name := ir.NewDeclNameAt(u.Pos(), ir.OTYPE, sym)
|
||||
s := types.NewNamed(name)
|
||||
s.SetUnderlying(t.Underlying())
|
||||
s.SetUnderlying(u)
|
||||
s.SetIsShape(true)
|
||||
name.SetType(s)
|
||||
name.SetTypecheck(1)
|
||||
// TODO: add methods to s that the bound has?
|
||||
Shaped[t] = s
|
||||
shaped[u] = s
|
||||
return s
|
||||
}
|
||||
|
||||
var snum int
|
||||
|
||||
var Shaped = map[*types.Type]*types.Type{}
|
||||
|
||||
func ShapifyList(targs []*types.Type) []*types.Type {
|
||||
r := make([]*types.Type, len(targs))
|
||||
for i, t := range targs {
|
||||
r[i] = Shapify(t)
|
||||
}
|
||||
return r
|
||||
}
|
||||
var shaped = map[*types.Type]*types.Type{}
|
||||
|
33
test/typeparam/shape1.go
Normal file
33
test/typeparam/shape1.go
Normal file
@ -0,0 +1,33 @@
|
||||
// run -gcflags=-G=3
|
||||
|
||||
// Copyright 2021 The Go Authors. All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package main
|
||||
|
||||
type I interface {
|
||||
foo() int
|
||||
}
|
||||
|
||||
// There should be a single instantiation of f in this program.
|
||||
func f[T I](x T) int {
|
||||
return x.foo()
|
||||
}
|
||||
|
||||
type squarer int
|
||||
|
||||
func (x squarer) foo() int {
|
||||
return int(x*x)
|
||||
}
|
||||
|
||||
type doubler int
|
||||
|
||||
func (x doubler) foo() int {
|
||||
return int(2*x)
|
||||
}
|
||||
|
||||
func main() {
|
||||
println(f(squarer(5)))
|
||||
println(f(doubler(5)))
|
||||
}
|
2
test/typeparam/shape1.out
Normal file
2
test/typeparam/shape1.out
Normal file
@ -0,0 +1,2 @@
|
||||
25
|
||||
10
|
Loading…
Reference in New Issue
Block a user