[llvm][NFC] Factored the default inlining advice

This is in preparation for the 'development' mode advisor. We currently
want to track what the default policy's decision would have been, this
refactoring makes it easier to do that.

Author: mtrofin

llvm/lib/Analysis/InlineAdvisor.cpp

@@ -84,7 +84,9 @@ class DefaultInlineAdvice : public InlineAdvice {
 
 } // namespace
 
-std::unique_ptr<InlineAdvice> DefaultInlineAdvisor::getAdvice(CallBase &CB) {
+llvm::Optional<llvm::InlineCost>
+getDefaultInlineAdvice(CallBase &CB, FunctionAnalysisManager &FAM,
+                       const InlineParams &Params) {
   Function &Caller = *CB.getCaller();
   ProfileSummaryInfo *PSI =
       FAM.getResult<ModuleAnalysisManagerFunctionProxy>(Caller)
@@ -111,10 +113,16 @@ std::unique_ptr<InlineAdvice> DefaultInlineAdvisor::getAdvice(CallBase &CB) {
     return getInlineCost(CB, Params, CalleeTTI, GetAssumptionCache, GetTLI,
                          GetBFI, PSI, RemarksEnabled ? &ORE : nullptr);
   };
-  auto OIC = llvm::shouldInline(CB, GetInlineCost, ORE,
-                                Params.EnableDeferral.hasValue() &&
-                                    Params.EnableDeferral.getValue());
-  return std::make_unique<DefaultInlineAdvice>(this, CB, OIC, ORE);
+  return llvm::shouldInline(CB, GetInlineCost, ORE,
+                            Params.EnableDeferral.hasValue() &&
+                                Params.EnableDeferral.getValue());
+}
+
+std::unique_ptr<InlineAdvice> DefaultInlineAdvisor::getAdvice(CallBase &CB) {
+  auto OIC = getDefaultInlineAdvice(CB, FAM, Params);
+  return std::make_unique<DefaultInlineAdvice>(
+      this, CB, OIC,
+      FAM.getResult<OptimizationRemarkEmitterAnalysis>(*CB.getCaller()));
 }
 
 InlineAdvice::InlineAdvice(InlineAdvisor *Advisor, CallBase &CB,