From: chi wu > Sent: 05 April 2023 09:48 > > Christoph Hellwig <hch@xxxxxxxxxxxxx> 于2023年4月5日周三 13:40写道: > > > > On Mon, Apr 03, 2023 at 09:53:04PM +0800, wuchi wrote: > > > - if (block > ext_block) > > > - return ext_pblk + (block - ext_block); > > > - else > > > - return ext_pblk - (ext_block - block); > > > + return ext_pblk + ((signed long long)block - (signed long long)ext_block); > > > > And what exactly is the value add here, except for turning an easy > > to parse statement into a complex expression using casts? > > > Yes,it will be more complex. the original intention is to reduce the > conditional branch. What is wrong with just: return ext_pblk + block - ext_block; (64bit + 32bit - 32bit) David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)