commit a210689f1a0e7839f5b3589fd57583e6ae20ded0
author Aart Bik <ajcbik@google.com> Wed May 04 14:00:55 2016 -0700
committer Aart Bik <ajcbik@google.com> Wed May 04 14:40:41 2016 -0700
tree 9b07a9a999c0fff883163b06e4eb0a92ede376fd
parent f5d1fbe2893803b22d57121ce80a7f44f484a438

Exploit NE/EQ tests on array length in BCE.

BUG=28585870

Change-Id: I382ffaf80dfb861f66eb0bfb6508e7d946a07e14

test/449-checker-bce/src/Main.java

diff --git a/test/449-checker-bce/src/Main.java b/test/449-checker-bce/src/Main.java
index 66e1d92..41771b5 100644
--- a/test/449-checker-bce/src/Main.java
+++ b/test/449-checker-bce/src/Main.java
@@ -927,6 +927,32 @@
     }
   }
 
+  /// CHECK-START: void Main.nonzeroLength(int[]) BCE (before)
+  /// CHECK-DAG: BoundsCheck
+  //
+  /// CHECK-START: void Main.nonzeroLength(int[]) BCE (after)
+  /// CHECK-NOT: BoundsCheck
+  /// CHECK-NOT: Deoptimize
+  public static void nonzeroLength(int[] a) {
+    if (a.length != 0) {
+      a[0] = 112;
+    }
+  }
+
+  /// CHECK-START: void Main.knownLength(int[]) BCE (before)
+  /// CHECK-DAG: BoundsCheck
+  /// CHECK-DAG: BoundsCheck
+  //
+  /// CHECK-START: void Main.knownLength(int[]) BCE (after)
+  /// CHECK-NOT: BoundsCheck
+  /// CHECK-NOT: Deoptimize
+  public static void knownLength(int[] a) {
+    if (a.length == 2) {
+      a[0] = -1;
+      a[1] = -2;
+    }
+  }
+
   static int[][] mA;
 
   /// CHECK-START: void Main.dynamicBCEAndIntrinsic(int) BCE (before)
@@ -1586,6 +1612,26 @@
       }
     }
 
+    nonzeroLength(array);
+    if (array[0] != 112) {
+      System.out.println("nonzero length failed!");
+    }
+
+    knownLength(array);
+    if (array[0] != 112 || array[1] != 1) {
+      System.out.println("nonzero length failed!");
+    }
+    array = new int[2];
+    knownLength(array);
+    if (array[0] != -1 || array[1] != -2) {
+      System.out.println("nonzero length failed!");
+    }
+
+    // Zero length array does not break.
+    array = new int[0];
+    nonzeroLength(array);
+    knownLength(array);
+
     mA = new int[4][4];
     for (int i = 0; i < 4; i++) {
       for (int j = 0; j < 4; j++) {

test/530-checker-loops2/src/Main.java

diff --git a/test/530-checker-loops2/src/Main.java b/test/530-checker-loops2/src/Main.java
index c644692..b12fbd6 100644
--- a/test/530-checker-loops2/src/Main.java
+++ b/test/530-checker-loops2/src/Main.java
@@ -710,8 +710,8 @@
         // making them a candidate for deoptimization based on constant indices.
         // Compiler should ensure the array loads are not subsequently hoisted
         // "above" the deoptimization "barrier" on the bounds.
-        a[0][i] = 1;
-        a[1][i] = 2;
+        a[1][i] = 1;
+        a[2][i] = 2;
         a[99][i] = 3;
       }
     }
@@ -1042,11 +1042,11 @@
     a = new int[100][10];
     expectEquals(55, dynamicBCEAndConstantIndices(x, a, 0, 10));
     for (int i = 0; i < 10; i++) {
-      expectEquals((i % 10) != 0 ? 1 : 0, a[0][i]);
-      expectEquals((i % 10) != 0 ? 2 : 0, a[1][i]);
+      expectEquals((i % 10) != 0 ? 1 : 0, a[1][i]);
+      expectEquals((i % 10) != 0 ? 2 : 0, a[2][i]);
       expectEquals((i % 10) != 0 ? 3 : 0, a[99][i]);
     }
-    a = new int[2][10];
+    a = new int[3][10];
     sResult = 0;
     try {
       expectEquals(55, dynamicBCEAndConstantIndices(x, a, 0, 10));
@@ -1054,8 +1054,8 @@
       sResult = 1;
     }
     expectEquals(1, sResult);
-    expectEquals(a[0][1], 1);
-    expectEquals(a[1][1], 2);
+    expectEquals(a[1][1], 1);
+    expectEquals(a[2][1], 2);
 
     // Dynamic BCE combined with constant indices of all types.
     boolean[] x1 = { true };