kazuyukitanimura commented on a change in pull request #34611: URL: https://github.com/apache/spark/pull/34611#discussion_r758204579
########## File path: sql/core/src/main/java/org/apache/spark/sql/execution/datasources/parquet/VectorizedPlainValuesReader.java ########## @@ -53,19 +53,50 @@ public void skip() { throw new UnsupportedOperationException(); } + private void updateCurrentByte() { + try { + currentByte = (byte) in.read(); + } catch (IOException e) { + throw new ParquetDecodingException("Failed to read a byte", e); + } + } + @Override public final void readBooleans(int total, WritableColumnVector c, int rowId) { - // TODO: properly vectorize this - for (int i = 0; i < total; i++) { - c.putBoolean(rowId + i, readBoolean()); + int i = 0; + if (bitOffset > 0) { + i = Math.min(8 - bitOffset, total); + c.putBooleans(rowId, i, currentByte, bitOffset); + bitOffset = (bitOffset + i) & 7; + } + for (; i + 7 < total; i += 8) { + updateCurrentByte(); + c.putBooleans(rowId + i, currentByte); + } + if (i < total) { + updateCurrentByte(); + bitOffset = total - i; + c.putBooleans(rowId + i, bitOffset, currentByte, 0); } } @Override public final void skipBooleans(int total) { - // TODO: properly vectorize this - for (int i = 0; i < total; i++) { - readBoolean(); + // Using >>3 instead of /8 below. The difference is important when (total-(8-bitOffset))<0. + // E.g. (-1)>>3=(-1) vs. (-1)/8=0. The latter incorrectly enters the if(numBytesToSkip>=0){. + // (total-(8-bitOffset))<0 means there will be still unread bits left in the currentByte. + // In that case, updateCurrentByte() should not be called. + int numBytesToSkip = (total - (8 - bitOffset)) >> 3; + bitOffset = (bitOffset + total) & 7; + if (numBytesToSkip >= 0) { Review comment: Thank you @sunchao for finding this! I missed it. Since this logic is error prone and I didn't like the long comments, I changed the method to follow the same structure as `readBooleans()`. I have also updated the test case to cover this case. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org