[llvm] [CodeGen][NPM] VirtRegRewriter: Set VirtReg flag (PR #148107)

[Vikram Hegde via llvm-commits]

https://github.com/vikramRH updated https://github.com/llvm/llvm-project/pull/148107

>From 90c6b461174aa5d6d5e9b8781c7972eca02e01cd Mon Sep 17 00:00:00 2001
From: vikhegde <vikram.hegde at amd.com>
Date: Thu, 10 Jul 2025 15:25:03 +0530
Subject: [PATCH] [CodeGen][NPM] VirtRegRewriter: Set VirtReg flag

---
 llvm/include/llvm/CodeGen/VirtRegMap.h | 8 ++++++++
 llvm/lib/CodeGen/VirtRegMap.cpp        | 2 ++
 2 files changed, 10 insertions(+)

diff --git a/llvm/include/llvm/CodeGen/VirtRegMap.h b/llvm/include/llvm/CodeGen/VirtRegMap.h
index 5ab3f7e742230..b5f962e0fb821 100644
--- a/llvm/include/llvm/CodeGen/VirtRegMap.h
+++ b/llvm/include/llvm/CodeGen/VirtRegMap.h
@@ -251,6 +251,14 @@ class VirtRegRewriterPass : public PassInfoMixin<VirtRegRewriterPass> {
 
   LLVM_ABI void printPipeline(raw_ostream &OS,
                               function_ref<StringRef(StringRef)>) const;
+
+  MachineFunctionProperties getSetProperties() const {
+    if (ClearVirtRegs) {
+      return MachineFunctionProperties().set(
+          MachineFunctionProperties::Property::NoVRegs);
+    }
+    return {};
+  }
 };
 
 } // end llvm namespace
diff --git a/llvm/lib/CodeGen/VirtRegMap.cpp b/llvm/lib/CodeGen/VirtRegMap.cpp
index 3d6ccba894e9c..99ba893d6f096 100644
--- a/llvm/lib/CodeGen/VirtRegMap.cpp
+++ b/llvm/lib/CodeGen/VirtRegMap.cpp
@@ -301,6 +301,8 @@ bool VirtRegRewriterLegacy::runOnMachineFunction(MachineFunction &MF) {
 PreservedAnalyses
 VirtRegRewriterPass::run(MachineFunction &MF,
                          MachineFunctionAnalysisManager &MFAM) {
+  MFPropsModifier _(*this, MF);
+
   VirtRegMap &VRM = MFAM.getResult<VirtRegMapAnalysis>(MF);
   LiveIntervals &LIS = MFAM.getResult<LiveIntervalsAnalysis>(MF);
   LiveRegMatrix &LRM = MFAM.getResult<LiveRegMatrixAnalysis>(MF);