[llvm] [FuncSpec] Only compute Latency bonus when necessary (PR #113159)

[Alexandros Lamprineas via llvm-commits]

================
@@ -154,33 +154,45 @@ static Constant *findConstantFor(Value *V, ConstMap &KnownConstants) {
   return KnownConstants.lookup(V);
 }
 
-Cost InstCostVisitor::getCodeSizeBonusFromPendingPHIs() {
+Cost InstCostVisitor::getCodeSizeSavingsFromPendingPHIs() {
   Cost CodeSize;
   while (!PendingPHIs.empty()) {
     Instruction *Phi = PendingPHIs.pop_back_val();
     // The pending PHIs could have been proven dead by now.
     if (isBlockExecutable(Phi->getParent()))
-      CodeSize += getUserCodeSizeBonus(Phi);
+      CodeSize += getCodeSizeSavingsForUser(Phi);
   }
   return CodeSize;
 }
 
 /// Compute the codesize savings for replacing argument \p A with constant \p C.
-Cost InstCostVisitor::getCodeSizeBonus(Argument *A, Constant *C) {
+Cost InstCostVisitor::getCodeSizeSavingsForArg(Argument *A, Constant *C) {
   LLVM_DEBUG(dbgs() << "FnSpecialization: Analysing bonus for constant: "
                     << C->getNameOrAsOperand() << "\n");
   Cost CodeSize;
   for (auto *U : A->users())
     if (auto *UI = dyn_cast<Instruction>(U))
       if (isBlockExecutable(UI->getParent()))
-        CodeSize += getUserCodeSizeBonus(UI, A, C);
+        CodeSize += getCodeSizeSavingsForUser(UI, A, C);
 
   LLVM_DEBUG(dbgs() << "FnSpecialization:   Accumulated bonus {CodeSize = "
                     << CodeSize << "} for argument " << *A << "\n");
   return CodeSize;
 }
 
-Cost InstCostVisitor::getLatencyBonus() {
+/// Compute the latency savings from replacing all arguments with constants for
+/// a specialization candidate. As this function computes the latency savings
+/// for all Instructions in KnownConstants at once, it should be called only
+/// after every instruction has been visited, i.e. after:
+///
+/// * getCodeSizeBonus has been run for every constant argument of a
----------------
labrinea wrote:

outdated function name

https://github.com/llvm/llvm-project/pull/113159