[clang] [llvm] [X86] Support branch hint (PR #97721)

[Shengchen Kan via cfe-commits]

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@@ -54,6 +55,14 @@
 
 using namespace llvm;
 
+static cl::opt<bool> EnableBranchHint("branch-hint",
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KanRobert wrote:

`enable-branch-hint` is more in line with our current naming habits

https://github.com/llvm/llvm-project/pull/97721