This patch enables the following transformations in the instruction
selector:
| Before | After |
|------------------+------------------------|
| and x3, x1, #0x1 | tb{,n}z w1, #0, #+0x78 |
| cmp x3, #0x0 | |
| b.{eq,ne} #+0x80 | |
|------------------+------------------------|
| cmp x0, #0x0 | cb{,n}z x0, #+0x48 |
| b.{eq,ne} #+0x4c | |
I have not seen these patterns beeing generated by turbofan, however the
stubs hit these cases frequently. A particular reason is that we are
turning operations that check for a Smi into a single `tbz`.
As a concequence, the interpreter is affected thanks to inlining
turbofan stubs into it's bytecode handlers. I have noticed the size of
the interpreter was reduced by 200 instructions.
BUG=
Review-Url: https://codereview.chromium.org/2022073002
Cr-Commit-Position: refs/heads/master@{#36632}