CodeGen: Stop checking for physregs in constrainRegClass #161795
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This constrainRegClass check would never pass for a physical register.
This is trying to constrain the register class of a physical register, which makes no sense.
It's nonsensical to call constrainRegClass on a physical register, and we should not see virtual registers here.
We do not need to reconstrain physical registers. Enables an additional fold for constant physregs.
It's nonsensical to call this function on a physical register.
cdevadas
reviewed
Oct 3, 2025
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| const TargetRegisterClass *MachineRegisterInfo::constrainRegClass( | ||
| Register Reg, const TargetRegisterClass *RC, unsigned MinNumRegs) { | ||
| if (Reg.isPhysical()) |
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What if someone unkonwingly uses this function post-RA?
cdevadas
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Oct 3, 2025
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October 3, 2025 12:20
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It's nonsensical to call this function on a physical register.
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It's nonsensical to call this function on a physical register.