[llvm] [SandboxIR] Add pointer-diff utility function (PR #110176)

[via llvm-commits]

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@@ -57,6 +61,35 @@ class Utils {
   memoryLocationGetOrNone(const Instruction *I) {
     return llvm::MemoryLocation::getOrNone(cast<llvm::Instruction>(I->Val));
   }
+  /// \Returns true if \p I1 accesses a memory location lower than \p I2.
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vporpo wrote:

I think we should also mention that it returns false if we can't determine the diff.

https://github.com/llvm/llvm-project/pull/110176