> On 2 Dec 2015, at 02:55, Vladimir Kozlov <vladimir.koz...@oracle.com> wrote: > > I reviewed 8143355 today and my main question is where are range checks? >
In this case the range checks are performed by the methods in Arrays, which call non-checking type-specific methods in ArraysSupport that in turn call vectorizedMismatch e.g: http://cr.openjdk.java.net/~psandoz/jdk9/JDK-8136924-arrays-mismatch-vectorized-unsafe/webrev/src/java.base/share/classes/java/util/Arrays.java.sdiff.html 2861 @HotSpotIntrinsicCandidate 2862 public static boolean equals(byte[] a, byte[] a2) { 2863 if (a==a2) 2864 return true; 2865 if (a==null || a2==null) 2866 return false; 2867 2868 int length = a.length; 2869 if (a2.length != length) 2870 return false; 2871 2872 return ArraysSupport.mismatch(a, a2, length) < 0; 2873 } 2907 public static boolean equals(byte[] a, int aFromIndex, int aToIndex, 2908 byte[] b, int bFromIndex, int bToIndex) { 2909 rangeCheck(a.length, aFromIndex, aToIndex); 2910 rangeCheck(b.length, bFromIndex, bToIndex); 2911 2912 int aLength = aToIndex - aFromIndex; 2913 int bLength = bToIndex - bFromIndex; 2914 if (aLength != bLength) 2915 return false; 2916 2917 return ArraysSupport.mismatch(a, aFromIndex, 2918 b, bFromIndex, 2919 aLength) < 0; 2920 } 5875 public static int compare(byte[] a, byte[] b) { 5876 if (a == b) 5877 return 0; 5878 if (a == null || b == null) 5879 return a == null ? -1 : 1; 5880 5881 int i = ArraysSupport.mismatch(a, b, 5882 Math.min(a.length, b.length)); 5883 if (i >= 0) { 5884 return Byte.compare(a[i], b[i]); 5885 } 5886 5887 return a.length - b.length; 5888 } 5950 public static int compare(byte[] a, int aFromIndex, int aToIndex, 5951 byte[] b, int bFromIndex, int bToIndex) { 5952 rangeCheck(a.length, aFromIndex, aToIndex); 5953 rangeCheck(b.length, bFromIndex, bToIndex); 5954 5955 int aLength = aToIndex - aFromIndex; 5956 int bLength = bToIndex - bFromIndex; 5957 int i = ArraysSupport.mismatch(a, aFromIndex, 5958 b, bFromIndex, 5959 Math.min(aLength, bLength)); 5960 if (i >= 0) { 5961 return Byte.compare(a[aFromIndex + i], b[bFromIndex + i]); 5962 } 5963 5964 return aLength - bLength; 5965 } There are existing tests in place verifying that exceptions are thrown for out of bounds conditions. Paul.
