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Diffstat (limited to 'gcc-4.9/libgo/go/runtime/mallocrand.go')
-rw-r--r--gcc-4.9/libgo/go/runtime/mallocrand.go93
1 files changed, 93 insertions, 0 deletions
diff --git a/gcc-4.9/libgo/go/runtime/mallocrand.go b/gcc-4.9/libgo/go/runtime/mallocrand.go
new file mode 100644
index 000000000..f1bcb89cf
--- /dev/null
+++ b/gcc-4.9/libgo/go/runtime/mallocrand.go
@@ -0,0 +1,93 @@
+// Copyright 2009 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.
+
+// +build ignore
+
+// Random malloc test.
+
+package main
+
+import (
+ "flag"
+ "math/rand"
+ "runtime"
+ "unsafe"
+)
+
+var chatty = flag.Bool("v", false, "chatty")
+
+var footprint uint64
+var allocated uint64
+
+func bigger() {
+ memstats := new(runtime.MemStats)
+ runtime.ReadMemStats(memstats)
+ if f := memstats.Sys; footprint < f {
+ footprint = f
+ if *chatty {
+ println("Footprint", footprint, " for ", allocated)
+ }
+ if footprint > 1e9 {
+ println("too big")
+ panic("fail")
+ }
+ }
+}
+
+// Prime the data structures by allocating one of
+// each block in order. After this, there should be
+// little reason to ask for more memory from the OS.
+func prime() {
+ for i := 0; i < 16; i++ {
+ b := runtime.Alloc(1 << uint(i))
+ runtime.Free(b)
+ }
+ for i := uintptr(0); i < 256; i++ {
+ b := runtime.Alloc(i << 12)
+ runtime.Free(b)
+ }
+}
+
+func memset(b *byte, c byte, n uintptr) {
+ np := uintptr(n)
+ for i := uintptr(0); i < np; i++ {
+ *(*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(b)) + i)) = c
+ }
+}
+
+func main() {
+ flag.Parse()
+ // prime()
+ var blocks [1]struct {
+ base *byte
+ siz uintptr
+ }
+ for i := 0; i < 1<<10; i++ {
+ if i%(1<<10) == 0 && *chatty {
+ println(i)
+ }
+ b := rand.Int() % len(blocks)
+ if blocks[b].base != nil {
+ // println("Free", blocks[b].siz, blocks[b].base)
+ runtime.Free(blocks[b].base)
+ blocks[b].base = nil
+ allocated -= uint64(blocks[b].siz)
+ continue
+ }
+ siz := uintptr(rand.Int() >> (11 + rand.Uint32()%20))
+ base := runtime.Alloc(siz)
+ // ptr := uintptr(syscall.BytePtr(base))+uintptr(siz/2)
+ // obj, size, ref, ok := allocator.find(ptr)
+ // if obj != base || *ref != 0 || !ok {
+ // println("find", siz, obj, ref, ok)
+ // panic("fail")
+ // }
+ blocks[b].base = base
+ blocks[b].siz = siz
+ allocated += uint64(siz)
+ // println("Alloc", siz, base)
+ memset(base, 0xbb, siz)
+ bigger()
+ }
+}