Fix java heap exhaustion in 159-app-image-fields test

Test: art/test/testrunner/testrunner.py
Bug: 144525957
Change-Id: I466e5e1a8a227ae35ccaa58b61755665192c295d

1 files changed, 37 insertions, 22 deletions

diff --git a/test/159-app-image-fields/src/Main.java b/test/159-app-image-fields/src/Main.java
index 47d0116a19..e7db1e1f16 100644
--- a/test/159-app-image-fields/src/Main.java
+++ b/test/159-app-image-fields/src/Main.java
@@ -61,29 +61,44 @@ public class Main {
         }
     }
 
+    private static int exhaustJavaHeap(Object[] data, int index, int size) {
+        Runtime.getRuntime().gc();
+        while (index != data.length && size != 0) {
+            try {
+                data[index] = new byte[size];
+                ++index;
+            } catch (OutOfMemoryError oome) {
+                size /= 2;
+            }
+        }
+        return index;
+    }
+
     public static Object eatAllMemory() {
-      Object[] result = null;
-      int size = 1000000;
-      while (result == null && size != 0) {
-          try {
-              result = new Object[size];
-          } catch (OutOfMemoryError oome) {
-              size /= 2;
-          }
-      }
-      if (result != null) {
-          int index = 0;
-          while (index != result.length && size != 0) {
-              try {
-                  result[index] = new byte[size];
-                  ++index;
-              } catch (OutOfMemoryError oome) {
-                  size /= 2;
-              }
-          }
-      }
-      return result;
-  }
+        Object[] result = null;
+        int size = 1000000;
+        // Make sure that there is no reclaimable memory in the heap. Otherwise we may throw
+        // OOME to prevent GC thrashing, even if later allocations may succeed.
+        Runtime.getRuntime().gc();
+        System.runFinalization();
+        // NOTE: There is a GC invocation in exhaustJavaHeap. So we don't need one here.
+
+        while (result == null && size != 0) {
+            try {
+                result = new Object[size];
+            } catch (OutOfMemoryError oome) {
+                size /= 2;
+            }
+        }
+        if (result != null) {
+            int index = 0;
+            // Repeat to ensure there is no space left on the heap.
+            index = exhaustJavaHeap(result, index, size);
+            index = exhaustJavaHeap(result, index, /*size*/ 4);
+            index = exhaustJavaHeap(result, index, /*size*/ 4);
+        }
+        return result;
+    }
 }
 
 // The naming is deliberate to take into account two different situations: