[clang] [llvm] [DataLayout] Introduce sentinel pointer value (PR #131557)

[Matt Arsenault via llvm-commits]

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@@ -13045,9 +13048,9 @@ This instruction requires several arguments:
    -  Caller and callee both have the calling convention ``fastcc`` or ``tailcc``.
    -  The call is in tail position (ret immediately follows call and ret
       uses value of call or is void).
-   -  Option ``-tailcallopt`` is enabled, ``llvm::GuaranteedTailCallOpt`` is 
+   -  Option ``-tailcallopt`` is enabled, ``llvm::GuaranteedTailCallOpt`` is
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arsenm wrote:

Unrelated whitespace changes 

https://github.com/llvm/llvm-project/pull/131557