RFR :7088419 : (L) Use x86 Hardware CRC32 Instruction with java.util.zip.CRC32 and java.util.zip.Adler32 (original) (raw)

David Holmes david.holmes at oracle.com
Fri May 17 02:15:00 UTC 2013

On 17/05/2013 11:58 AM, David Chase wrote:

On 2013-05-16, at 9:26 PM, David Holmes <david.holmes at oracle.com> wrote:

Dave,

This is certainly significant work! To get the mundane issues out of the way: - C code uses indent of 2 in places instead of 4 Are you referring to the #ifdefs and #defines? I just want to be sure, because that's what I see at 2 spaces.

No the C code:

JNIEXPORT jboolean JNICALL Java_java_util_zip_CRC32_init(JNIEnv env, jclass cls, jarray b, jboolean use_clmul) { / Get the CRC table from zip to initialize JNI. Our private copy is missing if not compiled for fastcrc32. */ crc_table = get_crc_table(); jint *buf = (env)->GetPrimitiveArrayCritical(env, b, 0); if (buf) { / Don't know for sure how big an unsigned long is, therefore copy one at a time. */ int i;

The above has indent 2 initially the moves to 8.

BTW while at this code I don't understand the issue with size of long and copying "one at a time". Where are the "unsigned longs"? and should we be using them if we don't even know they will be larger than unsigned ints?

David

David

More information about the core-libs-dev mailing list