cmd/compile/internal/inline: score call sites exposed by inlines

[gostls13.git] / test / recover4.go

diff --git a/test/recover4.go b/test/recover4.go
index 115d5a0eed767bcd4c48ab1b72543129c9805971..19b94948b8ce1499df535bbd2e59b9b1a64adb4f 100644 (file)
--- a/test/recover4.go
+++ b/test/recover4.go
@@ -1,7 +1,8 @@
-// +build linux darwin
 // run
 
-// Copyright 2015 The Go Authors.  All rights reserved.
+//go:build linux || darwin
+
+// Copyright 2015 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.
 
@@ -24,12 +25,13 @@ import (
        "log"
        "runtime/debug"
        "syscall"
-       "unsafe"
 )
 
 func memcopy(dst, src []byte) (n int, err error) {
        defer func() {
-               err = recover().(error)
+               if r, ok := recover().(error); ok {
+                       err = r
+               }
        }()
 
        for i := 0; i < len(dst) && i < len(src); i++ {
@@ -44,28 +46,31 @@ func main() {
        // so that memcopy can recover.
        debug.SetPanicOnFault(true)
 
-       // Map 64 kB block of data with 16 kB hole in middle.
-       data, err := syscall.Mmap(-1, 0, 64*1024, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_ANON|syscall.MAP_PRIVATE)
+       size := syscall.Getpagesize()
+
+       // Map 16 pages of data with a 4-page hole in the middle.
+       data, err := syscall.Mmap(-1, 0, 16*size, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_ANON|syscall.MAP_PRIVATE)
        if err != nil {
                log.Fatalf("mmap: %v", err)
        }
 
-       // Note: Cannot call syscall.Munmap, because Munmap checks
-       // that you are unmapping a whole region returned by Mmap.
-       // We are trying to unmap just a hole in the middle.
-       if _, _, err := syscall.Syscall(syscall.SYS_MUNMAP, uintptr(unsafe.Pointer(&data[32*1024])), 16*1024, 0); err != 0 {
-               log.Fatalf("munmap: %v", err)
+       // Create a hole in the mapping that's PROT_NONE.
+       // Note that we can't use munmap here because the Go runtime
+       // could create a mapping that ends up in this hole otherwise,
+       // invalidating the test.
+       hole := data[len(data)/2 : 3*(len(data)/4)]
+       if err := syscall.Mprotect(hole, syscall.PROT_NONE); err != nil {
+               log.Fatalf("mprotect: %v", err)
        }
 
-       other := make([]byte, 64*1024)
-
        // Check that memcopy returns the actual amount copied
-       // before the fault (32kB - 5, the offset we skip in the argument).
-       n, err := memcopy(data[5:], other)
+       // before the fault.
+       const offset = 5
+       n, err := memcopy(data[offset:], make([]byte, len(data)))
        if err == nil {
                log.Fatal("no error from memcopy across memory hole")
        }
-       if n != 32*1024-5 {
-               log.Fatal("memcopy returned %d, want %d", n, 32*1024-5)
+       if expect := len(data)/2 - offset; n != expect {
+               log.Fatalf("memcopy returned %d, want %d", n, expect)
        }
 }