fixup! Add comment

Author: jaidTw

llvm/lib/Target/RISCV/RISCVTargetMachine.cpp

@@ -570,6 +570,9 @@ void RISCVPassConfig::addPreEmitPass() {
     addPass(createMachineCopyPropagationPass(true));
   if (TM->getOptLevel() >= CodeGenOptLevel::Default)
     addPass(createRISCVLateBranchOptPass());
+  // The IndirectBranchTrackingPass inserts lpad and could have changed the
+  // basic block alignment. It must be done before Branch Relaxation to
+  // prevent the adjusted offset exceeding the branch range.
   addPass(createRISCVIndirectBranchTrackingPass());
   addPass(&BranchRelaxationPassID);
   addPass(createRISCVMakeCompressibleOptPass());