[llvm] Make some fixes to the LLVM Language Ref. (PR #137782)

[Kip Hamiltons via llvm-commits]

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@@ -465,11 +465,11 @@ added in the future:
     Non-general purpose registers still follow the standard c calling
     convention. Currently it is for x86_64 and AArch64 only.
 "``cxx_fast_tlscc``" - The `CXX_FAST_TLS` calling convention for access functions
-    Clang generates an access function to access C++-style TLS. The access
-    function generally has an entry block, an exit block and an initialization
-    block that is run at the first time. The entry and exit blocks can access
-    a few TLS IR variables, each access will be lowered to a platform-specific
-    sequence.
+    Clang generates an access function to access C++-style Thread Local Storage
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KipHamiltons wrote:

Just defining `TLS`. The rest is fixing line widths.

https://github.com/llvm/llvm-project/pull/137782