зеркало из https://github.com/CryptoPro/go.git
133 строки
3.2 KiB
Go
133 строки
3.2 KiB
Go
// run
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// +build amd64
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// +build linux darwin
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// Copyright 2016 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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import (
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"fmt"
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"syscall"
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)
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// Use global variables so the compiler
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// doesn't know that they are constants.
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var p = syscall.Getpagesize()
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var zero = 0
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var one = 1
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func main() {
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// Allocate 2 pages of memory.
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b, err := syscall.Mmap(-1, 0, 2*p, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_ANON|syscall.MAP_PRIVATE)
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if err != nil {
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panic(err)
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}
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// Mark the second page as faulting.
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err = syscall.Mprotect(b[p:], syscall.PROT_NONE)
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if err != nil {
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panic(err)
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}
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// Get a slice pointing to the last byte of the good page.
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x := b[p-one : p]
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test16(x)
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test16i(x, 0)
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test32(x)
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test32i(x, 0)
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test64(x)
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test64i(x, 0)
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}
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func test16(x []byte) uint16 {
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defer func() {
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r := recover()
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if r == nil {
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panic("no fault or bounds check failure happened")
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}
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s := fmt.Sprintf("%s", r)
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if s != "runtime error: index out of range [1] with length 1" {
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panic("bad panic: " + s)
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}
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}()
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// Try to read 2 bytes from x.
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return uint16(x[0]) | uint16(x[1])<<8
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// We expect to get an "index out of range" error from x[1].
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// If we promote the first load to a 2-byte load, it will segfault, which we don't want.
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}
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func test16i(x []byte, i int) uint16 {
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defer func() {
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r := recover()
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if r == nil {
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panic("no fault or bounds check failure happened")
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}
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s := fmt.Sprintf("%s", r)
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if s != "runtime error: index out of range [1] with length 1" {
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panic("bad panic: " + s)
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}
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}()
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return uint16(x[i]) | uint16(x[i+1])<<8
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}
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func test32(x []byte) uint32 {
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defer func() {
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r := recover()
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if r == nil {
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panic("no fault or bounds check failure happened")
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}
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s := fmt.Sprintf("%s", r)
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if s != "runtime error: index out of range [1] with length 1" {
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panic("bad panic: " + s)
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}
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}()
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return uint32(x[0]) | uint32(x[1])<<8 | uint32(x[2])<<16 | uint32(x[3])<<24
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}
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func test32i(x []byte, i int) uint32 {
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defer func() {
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r := recover()
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if r == nil {
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panic("no fault or bounds check failure happened")
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}
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s := fmt.Sprintf("%s", r)
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if s != "runtime error: index out of range [1] with length 1" {
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panic("bad panic: " + s)
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}
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}()
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return uint32(x[i]) | uint32(x[i+1])<<8 | uint32(x[i+2])<<16 | uint32(x[i+3])<<24
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}
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func test64(x []byte) uint64 {
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defer func() {
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r := recover()
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if r == nil {
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panic("no fault or bounds check failure happened")
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}
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s := fmt.Sprintf("%s", r)
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if s != "runtime error: index out of range [1] with length 1" {
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panic("bad panic: " + s)
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}
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}()
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return uint64(x[0]) | uint64(x[1])<<8 | uint64(x[2])<<16 | uint64(x[3])<<24 |
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uint64(x[4])<<32 | uint64(x[5])<<40 | uint64(x[6])<<48 | uint64(x[7])<<56
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}
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func test64i(x []byte, i int) uint64 {
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defer func() {
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r := recover()
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if r == nil {
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panic("no fault or bounds check failure happened")
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}
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s := fmt.Sprintf("%s", r)
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if s != "runtime error: index out of range [1] with length 1" {
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panic("bad panic: " + s)
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}
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}()
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return uint64(x[i+0]) | uint64(x[i+1])<<8 | uint64(x[i+2])<<16 | uint64(x[i+3])<<24 |
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uint64(x[i+4])<<32 | uint64(x[i+5])<<40 | uint64(x[i+6])<<48 | uint64(x[i+7])<<56
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}
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