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author | Matthew Dempsky <mdempsky@google.com> | 2021-04-21 02:11:15 -0700 |
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committer | Matthew Dempsky <mdempsky@google.com> | 2021-05-02 20:38:13 +0000 |
commit | fadad851a3222867b374e901ede9c4919594837f (patch) | |
tree | 7b4efe046ea2da139b27ce5091d0cbd058bdf331 /test | |
parent | 0d32d9e8a8784cf3ef39c471b73e502c51085b6d (diff) | |
download | go-fadad851a3222867b374e901ede9c4919594837f.tar.gz go-fadad851a3222867b374e901ede9c4919594837f.zip |
cmd/compile: implement unsafe.Add and unsafe.Slice
Updates #19367.
Updates #40481.
Change-Id: Iabd2afdd0d520e5d68fd9e6dedd013335a4b3886
Reviewed-on: https://go-review.googlesource.com/c/go/+/312214
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Trust: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Diffstat (limited to 'test')
-rw-r--r-- | test/unsafebuiltins.go | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/test/unsafebuiltins.go b/test/unsafebuiltins.go new file mode 100644 index 0000000000..c10f8084a7 --- /dev/null +++ b/test/unsafebuiltins.go @@ -0,0 +1,61 @@ +// run + +// 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 ( + "math" + "unsafe" +) + +const maxUintptr = 1 << (8 * unsafe.Sizeof(uintptr(0))) + +func main() { + var p [10]byte + + // unsafe.Add + { + p1 := unsafe.Pointer(&p[1]) + assert(unsafe.Add(p1, 1) == unsafe.Pointer(&p[2])) + assert(unsafe.Add(p1, -1) == unsafe.Pointer(&p[0])) + } + + // unsafe.Slice + { + s := unsafe.Slice(&p[0], len(p)) + assert(&s[0] == &p[0]) + assert(len(s) == len(p)) + assert(cap(s) == len(p)) + + // nil pointer + mustPanic(func() { _ = unsafe.Slice((*int)(nil), 0) }) + + // negative length + var neg int = -1 + mustPanic(func() { _ = unsafe.Slice(new(byte), neg) }) + + // length too large + var tooBig uint64 = math.MaxUint64 + mustPanic(func() { _ = unsafe.Slice(new(byte), tooBig) }) + + // size overflows address space + mustPanic(func() { _ = unsafe.Slice(new(uint64), maxUintptr/8) }) + mustPanic(func() { _ = unsafe.Slice(new(uint64), maxUintptr/8+1) }) + } +} + +func assert(ok bool) { + if !ok { + panic("FAIL") + } +} + +func mustPanic(f func()) { + defer func() { + assert(recover() != nil) + }() + f() +} |