On Wed, 2017-05-17 at 13:33 +0300, Alexey Dobriyan wrote: > > Joe Perches wrote: > > > > On Tue, 2017-05-16 at 23:42 +0300, Alexey Dobriyan wrote: > > > num_to_str() optimizes printing small integers [0..9], so the same > > > check higher in callchain is unnecessary. > > > > Doesn't the optimization exists for the frequent use of 0 > > in seq output? > > > > These seq_put_decimal calls are now slightly more expensive. > > That additional CALL instruction is hardly measurable so you're adding > branch to skip branch in the next function.
It's not the call instruction. num_to_str pushes the value first to stack and then sets up a loop to copy those chars to buffer. The current code immediately pushes to buffer. It's a fair amount of overhead. Have you measured it?
