[PATCH] D55295: LiveIntervals: Add removePhysReg

[Krzysztof Parzyszek via Phabricator via llvm-commits]

kparzysz added inline comments.


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Comment at: include/llvm/CodeGen/LiveIntervals.h:423
+    /// Reg. Subsequent uses should rely on on-demand recomputation.
+    void removePhysReg(unsigned Reg) {
+      for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units)
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qcolombet wrote:
> arsenm wrote:
> > kparzysz wrote:
> > > Could this be called `removePhysRegUnits`?  I think it would make it clearer what it actually does.
> > You are passing it a physreg, not a regunit so I think that would be more confusing. This is sort of hiding the implementation detail that the liveness of RegUnits is tracked
> Agree with Matt.
There exist register units that are shared between physical registers, so removing all units contained in a phys reg A can affect units from phys reg B.  In that sense removing register A affects information about register B.  It appears counterintuitive when you think of it as "removing a register", but makes sense when you think about "removing register's units".


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55295/new/

https://reviews.llvm.org/D55295