Add a flag to disable verification

Author: hiraditya

llvm/lib/Target/RISCV/RISCVLiveVariables.cpp

@@ -52,6 +52,10 @@ static cl::opt<unsigned> MaxVRegs("riscv-liveness-max-vregs",
  cl::desc("Maximum VRegs to track"),
  cl::init(1024), cl::Hidden);
 
+static cl::opt<unsigned> VerifyLiveness("riscv-liveness-verify",
+ cl::desc("Verify liveness information"),
+ cl::init(true), cl::Hidden);
+
 namespace {
 
 /// LivenessInfo - Stores liveness information for a basic block
@@ -109,9 +113,12 @@ class RISCVLiveVariables : public MachineFunctionPass {
  /// Print liveness information for debugging
  void print(raw_ostream &OS, const Module *M = nullptr) const override;
 
+ /// Verify the computed liveness information against MBB live-ins.
+ /// TODO: Extend verification to live-outs and instruction-level liveness.
  void verifyLiveness(MachineFunction &MF) const;
 
  /// Mark operands that kill a register
+ /// TODO: Add and remove kill flags as necessary.
  bool markKills(MachineFunction &MF);
 
 private:
@@ -486,8 +493,9 @@ bool RISCVLiveVariables::runOnMachineFunction(MachineFunction &MF) {
  print(dbgs());
  });
 
- verifyLiveness(MF);
- // This is an analysis pass, it doesn't modify the function
+ if (VerifyLiveness)
+ verifyLiveness(MF);
+
  return Changed;
 }