github.com/MerlinKodo/gvisor@v0.0.0-20231110090155-957f62ecf90e/pkg/gohacks/linkname_go113_unsafe.go (about)

     1  // Copyright 2023 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  //go:build go1.13
    16  
    17  // //go:linkname directives type-checked by checklinkname. Any other
    18  // non-linkname assumptions outside the Go 1 compatibility guarantee should
    19  // have an accompanied vet check or version guard build tag.
    20  
    21  // Package gohacks contains utilities for subverting the Go compiler.
    22  package gohacks
    23  
    24  import (
    25  	"unsafe"
    26  )
    27  
    28  // Note that go:linkname silently doesn't work if the local name is exported,
    29  // necessitating an indirection for exported functions.
    30  
    31  // Memmove is runtime.memmove, exported for SeqAtomicLoad/SeqAtomicTryLoad<T>.
    32  //
    33  //go:nosplit
    34  func Memmove(to, from unsafe.Pointer, n uintptr) {
    35  	memmove(to, from, n)
    36  }
    37  
    38  //go:linkname memmove runtime.memmove
    39  //go:noescape
    40  func memmove(to, from unsafe.Pointer, n uintptr)
    41  
    42  // Nanotime is runtime.nanotime.
    43  //
    44  //go:nosplit
    45  func Nanotime() int64 {
    46  	return nanotime()
    47  }
    48  
    49  //go:linkname nanotime runtime.nanotime
    50  //go:noescape
    51  func nanotime() int64