[clang] [llvm] [X86] Use X86AS::GS and X86AS::FS instead of 256 and 257. NFC (PR #109342)

[Phoebe Wang via cfe-commits]

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@@ -144,6 +144,7 @@ add_clang_library(clangCodeGen
   VarBypassDetector.cpp
 
   DEPENDS
+  vt_gen
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phoebewang wrote:

Why it depends?

https://github.com/llvm/llvm-project/pull/109342