diff options
Diffstat (limited to 'src/cmd/compile/internal/test/issue53888_test.go')
-rw-r--r-- | src/cmd/compile/internal/test/issue53888_test.go | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/test/issue53888_test.go b/src/cmd/compile/internal/test/issue53888_test.go new file mode 100644 index 0000000..0d5b13b --- /dev/null +++ b/src/cmd/compile/internal/test/issue53888_test.go @@ -0,0 +1,46 @@ +// Copyright 2022 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. + +//go:build !race + +package test + +import ( + "internal/testenv" + "testing" +) + +func TestAppendOfMake(t *testing.T) { + testenv.SkipIfOptimizationOff(t) + for n := 32; n < 33; n++ { // avoid stack allocation of make() + b := make([]byte, n) + f := func() { + b = append(b[:0], make([]byte, n)...) + } + if n := testing.AllocsPerRun(10, f); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + type S []byte + + s := make(S, n) + g := func() { + s = append(s[:0], make(S, n)...) + } + if n := testing.AllocsPerRun(10, g); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + h := func() { + s = append(s[:0], make([]byte, n)...) + } + if n := testing.AllocsPerRun(10, h); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + i := func() { + b = append(b[:0], make(S, n)...) + } + if n := testing.AllocsPerRun(10, i); n > 0 { + t.Errorf("got %f allocs, want 0", n) + } + } +} |