6 files changed, 69 insertions, 0 deletions
diff --git a/test/typeparam/dedup.dir/a.go b/test/typeparam/dedup.dir/a.go
new file mode 100644
index 0000000000..f5cb6dc762
--- /dev/null
+++ b/test/typeparam/dedup.dir/a.go
@@ -0,0 +1,10 @@
+// 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 a
+
+//go:noinline
+func F[T comparable](a, b T) bool {
+	return a == b
+}
diff --git a/test/typeparam/dedup.dir/b.go b/test/typeparam/dedup.dir/b.go
new file mode 100644
index 0000000000..ce037e2d8a
--- /dev/null
+++ b/test/typeparam/dedup.dir/b.go
@@ -0,0 +1,14 @@
+// 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 b
+
+import "a"
+
+func B() {
+	var x int64
+	println(a.F(&x, &x))
+	var y int32
+	println(a.F(&y, &y))
+}
diff --git a/test/typeparam/dedup.dir/c.go b/test/typeparam/dedup.dir/c.go
new file mode 100644
index 0000000000..11a5d97642
--- /dev/null
+++ b/test/typeparam/dedup.dir/c.go
@@ -0,0 +1,14 @@
+// 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 c
+
+import "a"
+
+func C() {
+	var x int64
+	println(a.F(&x, &x))
+	var y int32
+	println(a.F(&y, &y))
+}
diff --git a/test/typeparam/dedup.dir/main.go b/test/typeparam/dedup.dir/main.go
new file mode 100644
index 0000000000..dc3ff6f75f
--- /dev/null
+++ b/test/typeparam/dedup.dir/main.go
@@ -0,0 +1,15 @@
+// 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
+
+import (
+	"b"
+	"c"
+)
+
+func main() {
+	b.B()
+	c.C()
+}
diff --git a/test/typeparam/dedup.go b/test/typeparam/dedup.go
new file mode 100644
index 0000000000..dca4cf3a84
--- /dev/null
+++ b/test/typeparam/dedup.go
@@ -0,0 +1,12 @@
+// rundir -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.
+
+// 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
diff --git a/test/typeparam/dedup.out b/test/typeparam/dedup.out
new file mode 100644
index 0000000000..1140ff52e2
--- /dev/null
+++ b/test/typeparam/dedup.out
@@ -0,0 +1,4 @@
+true
+true
+true
+true