[llvm] f64eee1 - [NFC][InlineAdvisor] Inform advisor when the module is invalidated

[Mircea Trofin via llvm-commits]

Author: Mircea Trofin
Date: 2021-11-11T10:23:49-08:00
New Revision: f64eee162525d6298014772d5f99ab28b26aa238

URL: https://github.com/llvm/llvm-project/commit/f64eee162525d6298014772d5f99ab28b26aa238
DIFF: https://github.com/llvm/llvm-project/commit/f64eee162525d6298014772d5f99ab28b26aa238.diff

LOG: [NFC][InlineAdvisor] Inform advisor when the module is invalidated

This avoids unnecessary re-calculation of module-wide features in the
MLInlineAdvisor. In cases where function passes don't invalidate
functions (and, thus, don't invalidate the module), but we re-process a
CGSCC, we currently refreshed module features unnecessarily. The
overhead of fetching cached results (albeit they weren't themselves
invalidated) was noticeable in certain modules' compilations.

We don't want to just invalidate the advisor object, though, via the
analysis manager, because we'd then need to re-create expensive state
(like the model evaluator in the ML 'development' mode).

Reviewed By: phosek

Differential Revision: https://reviews.llvm.org/D113644

Added: 
    

Modified: 
    llvm/include/llvm/Analysis/InlineAdvisor.h
    llvm/include/llvm/Analysis/MLInlineAdvisor.h
    llvm/lib/Analysis/MLInlineAdvisor.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Analysis/InlineAdvisor.h b/llvm/include/llvm/Analysis/InlineAdvisor.h
index 8c928e5fc0a7d..9f9bc3a5e71b4 100644
--- a/llvm/include/llvm/Analysis/InlineAdvisor.h
+++ b/llvm/include/llvm/Analysis/InlineAdvisor.h
@@ -162,6 +162,12 @@ class InlineAdvisor {
   /// to prepare for a partial update.
   virtual void onPassExit() {}
 
+  /// Called when the module is invalidated. We let the advisor implementation
+  /// decide what to refresh - in the case of the development mode
+  /// implementation, for example, we wouldn't want to delete the whole object
+  /// and need to re-load the model evaluator.
+  virtual void onModuleInvalidated() {}
+
 protected:
   InlineAdvisor(Module &M, FunctionAnalysisManager &FAM);
   virtual std::unique_ptr<InlineAdvice> getAdviceImpl(CallBase &CB) = 0;
@@ -226,6 +232,8 @@ class InlineAdvisorAnalysis : public AnalysisInfoMixin<InlineAdvisorAnalysis> {
     Result(Module &M, ModuleAnalysisManager &MAM) : M(M), MAM(MAM) {}
     bool invalidate(Module &, const PreservedAnalyses &PA,
                     ModuleAnalysisManager::Invalidator &) {
+      if (Advisor && !PA.areAllPreserved())
+        Advisor->onModuleInvalidated();
       // Check whether the analysis has been explicitly invalidated. Otherwise,
       // it's stateless and remains preserved.
       auto PAC = PA.getChecker<InlineAdvisorAnalysis>();

diff  --git a/llvm/include/llvm/Analysis/MLInlineAdvisor.h b/llvm/include/llvm/Analysis/MLInlineAdvisor.h
index 54edbb823263b..a218561e61c73 100644
--- a/llvm/include/llvm/Analysis/MLInlineAdvisor.h
+++ b/llvm/include/llvm/Analysis/MLInlineAdvisor.h
@@ -38,6 +38,7 @@ class MLInlineAdvisor : public InlineAdvisor {
   bool isForcedToStop() const { return ForceStop; }
   int64_t getLocalCalls(Function &F);
   const MLModelRunner &getModelRunner() const { return *ModelRunner.get(); }
+  void onModuleInvalidated() override { Invalid = true; }
 
 protected:
   std::unique_ptr<InlineAdvice> getAdviceImpl(CallBase &CB) override;
@@ -55,6 +56,7 @@ class MLInlineAdvisor : public InlineAdvisor {
 private:
   int64_t getModuleIRSize() const;
 
+  bool Invalid = true;
   std::unique_ptr<CallGraph> CG;
 
   int64_t NodeCount = 0;

diff  --git a/llvm/lib/Analysis/MLInlineAdvisor.cpp b/llvm/lib/Analysis/MLInlineAdvisor.cpp
index 5b95ed223fd90..6fc4c42bdd718 100644
--- a/llvm/lib/Analysis/MLInlineAdvisor.cpp
+++ b/llvm/lib/Analysis/MLInlineAdvisor.cpp
@@ -116,6 +116,8 @@ MLInlineAdvisor::MLInlineAdvisor(Module &M, ModuleAnalysisManager &MAM,
 void MLInlineAdvisor::onPassEntry() {
   // Function passes executed between InlinerPass runs may have changed the
   // module-wide features.
+  if (!Invalid)
+    return;
   NodeCount = 0;
   EdgeCount = 0;
   for (auto &F : M)
@@ -123,6 +125,7 @@ void MLInlineAdvisor::onPassEntry() {
       ++NodeCount;
       EdgeCount += getLocalCalls(F);
     }
+  Invalid = false;
 }
 
 int64_t MLInlineAdvisor::getLocalCalls(Function &F) {