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-rw-r--r--test/stackobj2.go83
1 files changed, 83 insertions, 0 deletions
diff --git a/test/stackobj2.go b/test/stackobj2.go
new file mode 100644
index 0000000..a1abd9b
--- /dev/null
+++ b/test/stackobj2.go
@@ -0,0 +1,83 @@
+// run
+
+// Copyright 2018 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.
+
+package main
+
+import (
+ "fmt"
+ "runtime"
+)
+
+// linked list up the stack, to test lots of stack objects.
+
+type T struct {
+ // points to a heap object. Test will make sure it isn't freed.
+ data *int64
+ // next pointer for a linked list of stack objects
+ next *T
+ // duplicate of next, to stress test the pointer buffers
+ // used during stack tracing.
+ next2 *T
+}
+
+func main() {
+ makelist(nil, 10000)
+}
+
+func makelist(x *T, n int64) {
+ if n%2 != 0 {
+ panic("must be multiple of 2")
+ }
+ if n == 0 {
+ runtime.GC()
+ i := int64(1)
+ for ; x != nil; x, i = x.next, i+1 {
+ // Make sure x.data hasn't been collected.
+ if got := *x.data; got != i {
+ panic(fmt.Sprintf("bad data want %d, got %d", i, got))
+ }
+ }
+ return
+ }
+ // Put 2 objects in each frame, to test intra-frame pointers.
+ // Use both orderings to ensure the linked list isn't always in address order.
+ var a, b T
+ if n%3 == 0 {
+ a.data = newInt(n)
+ a.next = x
+ a.next2 = x
+ b.data = newInt(n - 1)
+ b.next = &a
+ b.next2 = &a
+ x = &b
+ } else {
+ b.data = newInt(n)
+ b.next = x
+ b.next2 = x
+ a.data = newInt(n - 1)
+ a.next = &b
+ a.next2 = &b
+ x = &a
+ }
+
+ makelist(x, n-2)
+}
+
+// big enough and pointer-y enough to not be tinyalloc'd
+type NotTiny struct {
+ n int64
+ p *byte
+}
+
+// newInt allocates n on the heap and returns a pointer to it.
+func newInt(n int64) *int64 {
+ h := &NotTiny{n: n}
+ p := &h.n
+ escape = p
+ return p
+}
+
+var escape *int64