Stack scanning: Find RegisterMap and unit-test it. Add decoding of the map.

Tests disabled, because there is a bug in System's LoadLibrary.

Change-Id: Ied3f4a31ce454f37c4d0f9caacd4ba03c4adb493
diff --git a/test/StackWalk/StackWalk.java b/test/StackWalk/StackWalk.java
new file mode 100644
index 0000000..f7c78ff
--- /dev/null
+++ b/test/StackWalk/StackWalk.java
@@ -0,0 +1,93 @@
+public class StackWalk {
+  public StackWalk() {
+  }
+
+  int f() {
+    g(1);
+    g(2);
+    return 0;
+  }
+
+  void g(int num_calls) {
+    if (num_calls == 1) {
+      System.out.println("1st call");
+    } else if (num_calls == 2) {
+      System.out.println("2nd call");
+    }
+    System.out.println(shlemiel());
+  }
+
+  String shlemiel() {
+    String s0 = new String("0");
+    String s1 = new String("1");
+    String s2 = new String("2");
+    String s3 = new String("3");
+    String s4 = new String("4");
+    String s5 = new String("5");
+    String s6 = new String("6");
+    String s7 = new String("7");
+    String s8 = new String("8");
+    String s9 = new String("9");
+    String s10 = new String("10");
+    String s11 = new String("11");
+    String s12 = new String("12");
+    String s13 = new String("13");
+    String s14 = new String("14");
+    String s15 = new String("15");
+    String s16 = new String("16");
+    String s17 = new String("17");
+    String s18 = new String("18");
+    String s19 = new String("19");
+    String s20 = new String("20");
+    String s = new String();
+    s += s0;
+    s += s1;
+    s += s2;
+    s += s3;
+    s += s4;
+    s += s5;
+    s += s6;
+    s += s7;
+    s += s8;
+    s += s9;
+    s += s10;
+    s += s11;
+    s += s12;
+    s += s13;
+    s += s14;
+    s += s15;
+    s += s16;
+    s += s17;
+    s += s18;
+    s += s19;
+    s += s20;
+
+    s += s6;
+    s += s5;
+    s += s2;
+    s += s3;
+
+    s10 = s + s10;
+    s10 += s20;
+
+    s20 += s10;
+    s = s17 + s20;
+
+    s4 = s18 = s19;
+    s += s4;
+    s += s18;
+    refmap(0);
+    return s;
+  }
+
+  native int refmap(int x);
+
+  static {
+    System.loadLibrary("arttest");
+  }
+
+  public static void main(String[] args) {
+    StackWalk st = new StackWalk();
+    st.f();
+  }
+}