[llvm] [RISCV] Replace PostRAScheduler with PostMachineScheduler (PR #68696)

[Wang Pengcheng via llvm-commits]

https://github.com/wangpc-pp updated https://github.com/llvm/llvm-project/pull/68696

>From b9e20f9e843f9d427e0e4408759ea1045be4b1a2 Mon Sep 17 00:00:00 2001
From: wangpc <wangpengcheng.pp at bytedance.com>
Date: Tue, 10 Oct 2023 20:12:20 +0800
Subject: [PATCH] [RISCV] Replace PostRAScheduler with PostMachineScheduler

Just like what other targets have done.

And this will make DAG mutations like MacroFusion take effect.
---
 llvm/lib/Target/RISCV/RISCVTargetMachine.cpp     | 2 ++
 llvm/test/CodeGen/RISCV/O3-pipeline.ll           | 2 +-
 llvm/test/CodeGen/RISCV/macro-fusion-lui-addi.ll | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Target/RISCV/RISCVTargetMachine.cpp b/llvm/lib/Target/RISCV/RISCVTargetMachine.cpp
index 1281528ea511a4d..651d24bae57263d 100644
--- a/llvm/lib/Target/RISCV/RISCVTargetMachine.cpp
+++ b/llvm/lib/Target/RISCV/RISCVTargetMachine.cpp
@@ -248,6 +248,8 @@ class RISCVPassConfig : public TargetPassConfig {
 public:
   RISCVPassConfig(RISCVTargetMachine &TM, PassManagerBase &PM)
       : TargetPassConfig(TM, PM) {
+    if (TM.getOptLevel() != CodeGenOptLevel::None)
+      substitutePass(&PostRASchedulerID, &PostMachineSchedulerID);
     setEnableSinkAndFold(EnableSinkFold);
   }
 
diff --git a/llvm/test/CodeGen/RISCV/O3-pipeline.ll b/llvm/test/CodeGen/RISCV/O3-pipeline.ll
index 277951782ce5ccb..30b6e1e541394d0 100644
--- a/llvm/test/CodeGen/RISCV/O3-pipeline.ll
+++ b/llvm/test/CodeGen/RISCV/O3-pipeline.ll
@@ -159,7 +159,7 @@
 ; CHECK-NEXT:       Insert KCFI indirect call checks
 ; CHECK-NEXT:       MachineDominator Tree Construction
 ; CHECK-NEXT:       Machine Natural Loop Construction
-; CHECK-NEXT:       Post RA top-down list latency scheduler
+; CHECK-NEXT:       PostRA Machine Instruction Scheduler
 ; CHECK-NEXT:       Analyze Machine Code For Garbage Collection
 ; CHECK-NEXT:       Machine Block Frequency Analysis
 ; CHECK-NEXT:       MachinePostDominator Tree Construction
diff --git a/llvm/test/CodeGen/RISCV/macro-fusion-lui-addi.ll b/llvm/test/CodeGen/RISCV/macro-fusion-lui-addi.ll
index 18d1449d0e2e837..498e6cf23ba3495 100644
--- a/llvm/test/CodeGen/RISCV/macro-fusion-lui-addi.ll
+++ b/llvm/test/CodeGen/RISCV/macro-fusion-lui-addi.ll
@@ -25,8 +25,8 @@ define void @foo(i32 signext %0, i32 signext %1) {
 ;
 ; FUSION-POSTRA-LABEL: foo:
 ; FUSION-POSTRA:       # %bb.0:
-; FUSION-POSTRA-NEXT:    lui a0, %hi(.L.str)
 ; FUSION-POSTRA-NEXT:    fcvt.s.w fa0, a1
+; FUSION-POSTRA-NEXT:    lui a0, %hi(.L.str)
 ; FUSION-POSTRA-NEXT:    addi a0, a0, %lo(.L.str)
 ; FUSION-POSTRA-NEXT:    tail bar at plt
   %3 = sitofp i32 %1 to float