[llvm] [RISCV] Add branch folding before branch relaxation (PR #134760)

[Matt Arsenault via llvm-commits]

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@@ -90,10 +90,13 @@ namespace {
 
   /// BranchFolderPass - Wrap branch folder in a machine function pass.
 class BranchFolderLegacy : public MachineFunctionPass {
+  bool EnableTailMerge;
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arsenm wrote:

Missing new pass manager handling (also should handle print/parse of the pass parameter). Also this should be done as a separate step 

https://github.com/llvm/llvm-project/pull/134760