vendor/llvm-project/llvmorg-19.1.0-rc1-0-ga4902a36d5c2

1 files changed, 24 insertions, 4 deletions

diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
index 161a3034e482..e474899fb548 100644
--- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
@@ -1692,9 +1692,12 @@ AliasResult BasicAAResult::aliasCheck(const Value *V1, LocationSize V1Size,
   if (!Pair.second) {
     auto &Entry = Pair.first->second;
     if (!Entry.isDefinitive()) {
-      // Remember that we used an assumption.
-      ++Entry.NumAssumptionUses;
+      // Remember that we used an assumption. This may either be a direct use
+      // of an assumption, or a use of an entry that may itself be based on an
+      // assumption.
       ++AAQI.NumAssumptionUses;
+      if (Entry.isAssumption())
+        ++Entry.NumAssumptionUses;
     }
     // Cache contains sorted {V1,V2} pairs but we should return original order.
     auto Result = Entry.Result;
@@ -1722,7 +1725,6 @@ AliasResult BasicAAResult::aliasCheck(const Value *V1, LocationSize V1Size,
   Entry.Result = Result;
   // Cache contains sorted {V1,V2} pairs.
   Entry.Result.swap(Swapped);
-  Entry.NumAssumptionUses = -1;
 
   // If the assumption has been disproven, remove any results that may have
   // been based on this assumption. Do this after the Entry updates above to
@@ -1734,8 +1736,26 @@ AliasResult BasicAAResult::aliasCheck(const Value *V1, LocationSize V1Size,
   // The result may still be based on assumptions higher up in the chain.
   // Remember it, so it can be purged from the cache later.
   if (OrigNumAssumptionUses != AAQI.NumAssumptionUses &&
-      Result != AliasResult::MayAlias)
+      Result != AliasResult::MayAlias) {
     AAQI.AssumptionBasedResults.push_back(Locs);
+    Entry.NumAssumptionUses = AAQueryInfo::CacheEntry::AssumptionBased;
+  } else {
+    Entry.NumAssumptionUses = AAQueryInfo::CacheEntry::Definitive;
+  }
+
+  // Depth is incremented before this function is called, so Depth==1 indicates
+  // a root query.
+  if (AAQI.Depth == 1) {
+    // Any remaining assumption based results must be based on proven
+    // assumptions, so convert them to definitive results.
+    for (const auto &Loc : AAQI.AssumptionBasedResults) {
+      auto It = AAQI.AliasCache.find(Loc);
+      if (It != AAQI.AliasCache.end())
+        It->second.NumAssumptionUses = AAQueryInfo::CacheEntry::Definitive;
+    }
+    AAQI.AssumptionBasedResults.clear();
+    AAQI.NumAssumptionUses = 0;
+  }
   return Result;
 }