[GreedyRA ORE] Compute ORE stats if extra analysis is enabled

[skatkov]

Summary

To save compile time, avoid computation of stats if ORE will not emit it.
The motivation is to add more stats and compute it only if it will dumped.

[reames]

LGTM

llvm/lib/CodeGen/RegAllocGreedy.cpp

private:
   bool isUnusedCalleeSavedReg(MCRegister PhysReg) const;
 
   /// Compute and report the number of spills and reloads for a loop.
   void reportNumberOfSplillsReloads(MachineLoop *L, unsigned &Reloads,
                                     unsigned &FoldedReloads, unsigned &Spills,
                                     unsigned &FoldedSpills);
 
   /// Report the number of spills and reloads for each loop.
-  void reportNumberOfSplillsReloads() {
-    for (MachineLoop *L : *Loops) {
-      unsigned Reloads, FoldedReloads, Spills, FoldedSpills;
-      reportNumberOfSplillsReloads(L, Reloads, FoldedReloads, Spills,
-                                   FoldedSpills);
-    }
-  }
+  void reportNumberOfSplillsReloads();
 };
 
 } // end anonymous namespace
 
 char RAGreedy::ID = 0;
 char &llvm::RAGreedyID = RAGreedy::ID;
 
 INITIALIZE_PASS_BEGIN(RAGreedy, "greedy",
ORE->emit([&]() {
       if (FoldedReloads)
         R << NV("NumFoldedReloads", FoldedReloads) << " folded reloads ";
       R << "generated in loop";
       return R;
     });
   }
 }
 
+void RAGreedy::reportNumberOfSplillsReloads() {
+  if (!ORE->allowExtraAnalysis(DEBUG_TYPE))
+    return;
+  for (MachineLoop *L : *Loops) {
+    unsigned Reloads, FoldedReloads, Spills, FoldedSpills;
+    reportNumberOfSplillsReloads(L, Reloads, FoldedReloads, Spills,
+                                 FoldedSpills);
+  }
+}
+
 bool RAGreedy::runOnMachineFunction(MachineFunction &mf) {
   LLVM_DEBUG(dbgs() << "********** GREEDY REGISTER ALLOCATION **********\n"
                     << "********** Function: " << mf.getName() << '\n');
 
   MF = &mf;
   TRI = MF->getSubtarget().getRegisterInfo();
   TII = MF->getSubtarget().getInstrInfo();
   RCI.runOnMachineFunction(mf);