BOLT : Use function reorder only

[Snow-Ning]

I want the binary optimized by bolt to reorder only the hot functions and generate .text sections for the reorder functions without modifying the size of any instruction. How should I set the options?

[Snow-Ning]

Hello，I want the binary optimized by bolt to reorder only the hot functions and generate .text sections for the reorder functions without modifying the size of any instruction. How should I set the options?

[llvmbot]

@llvm/issue-subscribers-bolt

Author: None (Snow-Ning)

I want the binary optimized by bolt to reorder only the hot functions and generate .text sections for the reorder functions without modifying the size of any instruction. How should I set the options?

[maksfb]

We don't have any special mode that will do exactly as you ask. May I ask why you want it? We have a flag --keep-nops that will leave functions in a state closer to what you want, but there are other passes that can modify instructions even when no optimizations are specified. The caveat with nops is that the alignment will get affected by the new layout, i.e. probably will have to combine it with --align-functions.