[llvm] r369091 - AssumptionCache: remove old affected values after RAUW.

[Tim Northover via llvm-commits]

Author: tnorthover
Date: Fri Aug 16 02:34:27 2019
New Revision: 369091

URL: http://llvm.org/viewvc/llvm-project?rev=369091&view=rev
Log:
AssumptionCache: remove old affected values after RAUW.

If they're left in the cache then they can't be removed efficiently when the
cache is notified to unlink a @llvm.assume call, and that can lead to values
from different functions entirely remaining there.

Modified:
    llvm/trunk/include/llvm/Analysis/AssumptionCache.h
    llvm/trunk/lib/Analysis/AssumptionCache.cpp

Modified: llvm/trunk/include/llvm/Analysis/AssumptionCache.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/AssumptionCache.h?rev=369091&r1=369090&r2=369091&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/AssumptionCache.h (original)
+++ llvm/trunk/include/llvm/Analysis/AssumptionCache.h Fri Aug 16 02:34:27 2019
@@ -73,8 +73,8 @@ class AssumptionCache {
   /// Get the vector of assumptions which affect a value from the cache.
   SmallVector<WeakTrackingVH, 1> &getOrInsertAffectedValues(Value *V);
 
-  /// Copy affected values in the cache for OV to be affected values for NV.
-  void copyAffectedValuesInCache(Value *OV, Value *NV);
+  /// Move affected values in the cache for OV to be affected values for NV.
+  void transferAffectedValuesInCache(Value *OV, Value *NV);
 
   /// Flag tracking whether we have scanned the function yet.
   ///

Modified: llvm/trunk/lib/Analysis/AssumptionCache.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/AssumptionCache.cpp?rev=369091&r1=369090&r2=369091&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/AssumptionCache.cpp (original)
+++ llvm/trunk/lib/Analysis/AssumptionCache.cpp Fri Aug 16 02:34:27 2019
@@ -140,7 +140,7 @@ void AssumptionCache::AffectedValueCallb
   // 'this' now dangles!
 }
 
-void AssumptionCache::copyAffectedValuesInCache(Value *OV, Value *NV) {
+void AssumptionCache::transferAffectedValuesInCache(Value *OV, Value *NV) {
   auto &NAVV = getOrInsertAffectedValues(NV);
   auto AVI = AffectedValues.find(OV);
   if (AVI == AffectedValues.end())
@@ -149,6 +149,7 @@ void AssumptionCache::copyAffectedValues
   for (auto &A : AVI->second)
     if (std::find(NAVV.begin(), NAVV.end(), A) == NAVV.end())
       NAVV.push_back(A);
+  AffectedValues.erase(OV);
 }
 
 void AssumptionCache::AffectedValueCallbackVH::allUsesReplacedWith(Value *NV) {
@@ -157,7 +158,7 @@ void AssumptionCache::AffectedValueCallb
 
   // Any assumptions that affected this value now affect the new value.
 
-  AC->copyAffectedValuesInCache(getValPtr(), NV);
+  AC->transferAffectedValuesInCache(getValPtr(), NV);
   // 'this' now might dangle! If the AffectedValues map was resized to add an
   // entry for NV then this object might have been destroyed in favor of some
   // copy in the grown map.