[PATCH] D26803: Fix known zero bits for addrspacecast

[Yaxun Liu via llvm-commits]

yaxunl marked an inline comment as done.
yaxunl added inline comments.


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Comment at: lib/Analysis/ValueTracking.cpp:1028-1029
   case Instruction::IntToPtr:
   case Instruction::AddrSpaceCast: // Pointers could be different sizes.
     // Fall through and handle them the same as zext/trunc.
     LLVM_FALLTHROUGH;
----------------
arsenm wrote:
> yaxunl wrote:
> > arsenm wrote:
> > > AddrSpaceCast should probably just be removed from the switch
> > Some optimizations will be lost if it is removed.
> Those optimizations are also broken
But you are right. We cannot assume anything about the bits after addrspacecast.


https://reviews.llvm.org/D26803