go/test/typeparam/dedup.go

// rundir

// 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.

// Note: this doesn't really test the deduplication of
// instantiations. It just provides an easy mechanism to build a
// binary that you can then check with objdump manually to make sure
// deduplication is happening. TODO: automate this somehow?

package ignored
all: avoid use of cmd/compile -G flag in tests The next CL will remove the -G flag, effectively hard-coding it to its current default (-G=3). Change-Id: Ib4743b529206928f9f1cca9fdb19989728327831 Reviewed-on: https://go-review.googlesource.com/c/go/+/388534 Reviewed-by: Keith Randall <khr@golang.org> Trust: Matthew Dempsky <mdempsky@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Gopher Robot <gobot@golang.org> 2022-02-28 22:32:19 +00:00			`// rundir`
[dev.typeparams] cmd/compile: put shape types in their own package Put shape types in the top level package called ".shape". Name them using the serialization of the shape name, instead of the .shapeN names. This allows the linker to deduplicate instantiations across packages. Not sure that this is entirely correct, as shapes in this package may reference other packages (e.g. a field of a struct). But it seems to work for now. For the added test, when you look at the resulting binary (use the -k option with run.go) it has only one instantiation of F, and 4 call sites: $ objdump -d a.exe \| grep _a\.F 1053cb0: e8 8b 00 00 00 callq 139 <_a.F[.shape.uint8]> 1053ce9: e8 52 00 00 00 callq 82 <_a.F[.shape.uint8]> _a.F[.shape.uint8]: 1053d90: e8 ab ff ff ff callq -85 <_a.F[.shape.uint8]> 1053dc9: e8 72 ff ff ff callq -142 <_a.F[.shape.*uint8]> Change-Id: I627f7e50210aabe4a10d0e2717d87b75ac82e99b Reviewed-on: https://go-review.googlesource.com/c/go/+/339595 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> 2021-08-04 02:33:01 +00:00
			`// 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.`

			`// Note: this doesn't really test the deduplication of`
			`// instantiations. It just provides an easy mechanism to build a`
			`// binary that you can then check with objdump manually to make sure`
			`// deduplication is happening. TODO: automate this somehow?`

			`package ignored`