[llvm] [X86] Add support for indirect branch tracking in jump tables (PR #77679)

[Nicholas Mosier via llvm-commits]

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@@ -199,6 +199,7 @@ void initializeX86ReturnThunksPass(PassRegistry &);
 void initializeX86SpeculativeExecutionSideEffectSuppressionPass(PassRegistry &);
 void initializeX86SpeculativeLoadHardeningPassPass(PassRegistry &);
 void initializeX86TileConfigPass(PassRegistry &);
+void initializeX86IndirectBranchTrackingPassPass(PassRegistry &);
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nmosier wrote:

I added that so that it could be run via `-run-pass=x86-ibt`, as required in the test I added (indirect-branch-tracking-jt.mir). I can submit separate patch for it, but this patch will then be dependent on that one.

https://github.com/llvm/llvm-project/pull/77679