[llvm] [RISCV] Move RISCVIndirectBranchTracking before Branch Relaxation (PR #139993)

[Sam Elliott via llvm-commits]

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@@ -570,6 +570,7 @@ void RISCVPassConfig::addPreEmitPass() {
     addPass(createMachineCopyPropagationPass(true));
   if (TM->getOptLevel() >= CodeGenOptLevel::Default)
     addPass(createRISCVLateBranchOptPass());
+  addPass(createRISCVIndirectBranchTrackingPass());
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lenary wrote:

Please can you add your message as a comment before this line? Correctly handling late passes with these kinds of target-specific dependencies is difficult, documenting the relative ordering constraints will help with future maintenance.

I don't expect a comment for every pass added, but given you know the reasoning for this ordering, we can write it down.

https://github.com/llvm/llvm-project/pull/139993