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

[Alexandros Lamprineas via llvm-commits]

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@@ -875,24 +885,23 @@ bool FunctionSpecializer::findSpecializations(Function *F, unsigned FuncSize,
       AllSpecs[Index].CallSites.push_back(&CS);
     } else {
       // Calculate the specialisation gain.
-      Bonus B;
+      Cost CodeSize;
       unsigned Score = 0;
       InstCostVisitor Visitor = getInstCostVisitorFor(F);
       for (ArgInfo &A : S.Args) {
-        B += Visitor.getSpecializationBonus(A.Formal, A.Actual);
+        CodeSize += Visitor.getCodeSizeBonus(A.Formal, A.Actual);
         Score += getInliningBonus(A.Formal, A.Actual);
       }
-      B += Visitor.getBonusFromPendingPHIs();
-
+      CodeSize += Visitor.getCodeSizeBonusFromPendingPHIs();
 
       LLVM_DEBUG(dbgs() << "FnSpecialization: Specialization bonus {CodeSize = "
-                        << B.CodeSize << ", Latency = " << B.Latency
-                        << ", Inlining = " << Score << "}\n");
+                        << CodeSize << ", Inlining = " << Score << "}\n");
 
+      Bonus B = {CodeSize, 0};
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labrinea wrote:

The Bonus struct seems redundant now. We should probably remove its refinition from the header file. I would replace B with `Cost CodeSizeSavings`.

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