1 files changed, 93 insertions, 0 deletions
diff --git a/libgo/go/runtime/mallocrand.go b/libgo/go/runtime/mallocrand.go
new file mode 100644
index 00000000000..f1bcb89cfa4
--- /dev/null
+++ b/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()
+	}
+}