[llvm] [WIP] Extend data layout to add non zero null value for address space. (PR #83109)

[Pierre van Houtryve via llvm-commits]

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@@ -164,6 +165,8 @@ class DataLayout {
   /// well-defined bitwise representation.
   SmallVector<unsigned, 8> NonIntegralAddressSpaces;
 
+  DenseMap<uint64_t, uint64_t> AddrSpaceToNonZeroValueMap;
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Pierre-vh wrote:

This should probably use APInt, as I think a pointer isn't guaranteed to be >=64 bits - we can have fat pointers that are bigger than that.

https://github.com/llvm/llvm-project/pull/83109