As a continuation of #83109, I audited the places where we iterate over all the registers in LSRA code base. I would categorize it:
-
Most of them are in #ifdef DEBUG
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Few are at the beginning of methods like allocateRegister() and resolveRegister(). The one in allocateRegister() can be done better during RegisterRecord initialization perhaps or creating intervals.
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Then, there are instances where they happen during building interval or allocation.
- In
resetAllRegistersState(), we reset the assigned interval at block boundaries for minopts.
- In
processStartBlockStartLocations(), we can optimize it to just iterate on liveRegs mask with bitwise iterator instead of for-loop.
- In
addRefsForPhysRegMask() - Used during kill positions, Here too, should be able to use bitwise iterator or bitscanforward technique.
As a continuation of #83109, I audited the places where we iterate over all the registers in LSRA code base. I would categorize it:
Most of them are in
#ifdef DEBUGFew are at the beginning of methods like
allocateRegister()andresolveRegister(). The one inallocateRegister()can be done better duringRegisterRecordinitialization perhaps or creating intervals.Then, there are instances where they happen during building interval or allocation.
resetAllRegistersState(), we reset the assigned interval at block boundaries for minopts.processStartBlockStartLocations(), we can optimize it to just iterate on liveRegs mask with bitwise iterator instead of for-loop.addRefsForPhysRegMask()- Used during kill positions, Here too, should be able to use bitwise iterator or bitscanforward technique.