[PATCH] D42357: Under limitation of allocated buffer, inplace_merge() does NOT take usage of partial allocated buffer but applies native rotate directly.

[WeiChungChang via Phabricator via cfe-commits]

WeiChungChang added a comment.

Here gives the comparison after fix.

F5783231: o1.png <https://reviews.llvm.org/F5783231>

It is better now but still slower; also, one could notice the standard variance (each round the execution time is unstable even the input is uniform)

The problem will be shown on the other ticket.

|             | full | 25%      | 12.5% | 6.25% | 3.125% |
| LLVM  Opt 1 | 0.2401988  | 0.407111 | 0.8510433   | 1.2216213   | 1.3857887    |
| LLVM        | 0.238614667  | 0.733295778      | 1.137285111   | 1.348671667   | 1.603639556    |
| GCC         | 0.368778444  | 0.351659222      | 0.532976333   | 0.660785778   | 0.832495444    |
|




Repository:
  rCXX libc++

https://reviews.llvm.org/D42357