From e8555cfd193c8de5a3de29275148731b29f6e176 Mon Sep 17 00:00:00 2001
From: Richard-Qin-X <richard.qin.001@gmail.com>
Date: Wed, 19 Aug 2026 17:50:30 +0800
Subject: [CodeGen] Unify LLVM branch folding pipeline

---
 .../lib/CodeGen/MachineOptimizationPipeline.cpp    | 28 ++++++++++------------
 1 file changed, 12 insertions(+), 16 deletions(-)

(limited to 'backend/lib/CodeGen/MachineOptimizationPipeline.cpp')

diff --git a/backend/lib/CodeGen/MachineOptimizationPipeline.cpp b/backend/lib/CodeGen/MachineOptimizationPipeline.cpp
index 817b2ca..7634ecd 100644
--- a/backend/lib/CodeGen/MachineOptimizationPipeline.cpp
+++ b/backend/lib/CodeGen/MachineOptimizationPipeline.cpp
@@ -21,7 +21,6 @@
 #include "rcc/CodeGen/MachineSink.h"
 #include "rcc/CodeGen/MachineStackSlotColoring.h"
 #include "rcc/CodeGen/MachineTailDuplication.h"
-#include "rcc/CodeGen/MachineTailMerge.h"
 #include "rcc/CodeGen/PostRAScheduler.h"
 #include "rcc/CodeGen/PrologueEpilogueInsertion.h"
 
@@ -69,11 +68,8 @@ addSelectedSSAOptimizationPipeline(MachineFunctionPassManager &Pipeline,
 
 Expected<void> addPreRegisterAllocationOptimizationPipeline(
     MachineFunctionPassManager &Pipeline, const MachineOptimizationPipelineTargetInfo &TargetInfo) {
-  auto Added = addPass<MachineBranchOptimizationPass>(Pipeline, TargetInfo.InstrInfo);
-  if (!Added)
-    return std::unexpected(Added.error());
-  Added = addPass<MachineCombinerPass>(Pipeline, TargetInfo.Combiner,
-                                       MachineCombinerStage::PreRegisterAllocation);
+  auto Added = addPass<MachineCombinerPass>(Pipeline, TargetInfo.Combiner,
+                                            MachineCombinerStage::PreRegisterAllocation);
   if (!Added)
     return std::unexpected(Added.error());
   return addPass<MachineSchedulerPass>(Pipeline, TargetInfo.SchedulingModel);
@@ -102,28 +98,28 @@ addPostRegisterAllocationPipeline(MachineFunctionPassManager &Pipeline,
   Added = addPass<PrologueEpilogueInsertionPass>(Pipeline, TargetInfo.FrameLowering);
   if (!Added)
     return std::unexpected(Added.error());
-  Added = addPass<ExpandPostRAPseudosPass>(Pipeline, TargetInfo.PseudoExpansion);
+  Added = addPass<MachineBranchOptimizationPass>(Pipeline, TargetInfo.InstrInfo);
   if (!Added)
     return std::unexpected(Added.error());
-  Added = addPass<PostRASchedulerPass>(Pipeline, TargetInfo.SchedulingModel);
+  Added = addPass<MachineTailDuplicationPass>(Pipeline, TargetInfo.InstrInfo);
   if (!Added)
     return std::unexpected(Added.error());
-  Added = addPass<MachineTailDuplicationPass>(Pipeline, TargetInfo.InstrInfo);
+  Added = addPass<MachineCopyPropagationPass>(
+      Pipeline, TargetInfo.InstrInfo,
+      MachineCopyPropagationOptions{.UseTargetCopyInstructions =
+                                        Options.UseTargetCopyInstructions});
   if (!Added)
     return std::unexpected(Added.error());
-  Added = addPass<MachineTailMergePass>(Pipeline, TargetInfo.InstrInfo);
+  Added = addPass<ExpandPostRAPseudosPass>(Pipeline, TargetInfo.PseudoExpansion);
   if (!Added)
     return std::unexpected(Added.error());
-  Added = addPass<MachineBlockPlacementPass>(Pipeline);
+  Added = addPass<PostRASchedulerPass>(Pipeline, TargetInfo.SchedulingModel);
   if (!Added)
     return std::unexpected(Added.error());
-  Added = addPass<MachineFallthroughPass>(Pipeline, TargetInfo.InstrInfo);
+  Added = addPass<MachineBlockPlacementPass>(Pipeline);
   if (!Added)
     return std::unexpected(Added.error());
-  Added = addPass<MachineCopyPropagationPass>(
-      Pipeline, TargetInfo.InstrInfo,
-      MachineCopyPropagationOptions{.UseTargetCopyInstructions =
-                                        Options.UseTargetCopyInstructions});
+  Added = addPass<MachineFallthroughPass>(Pipeline, TargetInfo.InstrInfo);
   if (!Added)
     return std::unexpected(Added.error());
   Added = addPass<MachineBranchRelaxationPass>(Pipeline, TargetInfo.InstrInfo);
-- 
cgit v1.2.3