Skip to content
Commit 56d6ccd4 authored by Craig Topper's avatar Craig Topper
Browse files

[X86] Update register RCL/RCR by 1 and immediate scheduling for Intel CPUs

Most Intel CPU scheduler files lumped the immediate and 1 instructions
together, but uops.info shows they are quite different.

For the most part the by 1 instructions were pretty accurate to the uops.info
data except the latency was 3 instead of 2 as uops.info indicates.

The by immediate instructions need 7 or 8 uops and have higher latency.

It looks like the 8-bit by immediate instructions may need even more
uops, but I just lumped them with the 16/32/64.

Noticed while checking out PR53648. So mostly I cared about the by 1
instructions.

Reviewed By: RKSimon, pengfei

Differential Revision: https://reviews.llvm.org/D119217
parent c1512250
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment