[llvm] r367581 - [Attributor][FIX] Indicate a missing update change

[Johannes Doerfert via llvm-commits]

Author: jdoerfert
Date: Thu Aug  1 09:21:54 2019
New Revision: 367581

URL: http://llvm.org/viewvc/llvm-project?rev=367581&view=rev
Log:
[Attributor][FIX] Indicate a missing update change

User of AAReturnedValues need to know if HasOverdefinedReturnedCalls
changed from false to true as it will impact the result of the return
value traversal (calls are not ignored anymore).

This will be tested with the tests in D59978.

Modified:
    llvm/trunk/lib/Transforms/IPO/Attributor.cpp

Modified: llvm/trunk/lib/Transforms/IPO/Attributor.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/Attributor.cpp?rev=367581&r1=367580&r2=367581&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/Attributor.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/Attributor.cpp Thu Aug  1 09:21:54 2019
@@ -722,6 +722,9 @@ ChangeStatus AAReturnedValuesImpl::updat
   decltype(ReturnedValues) AddRVs;
   bool HasCallSite = false;
 
+  // Keep track of any change to trigger updates on dependent attributes.
+  ChangeStatus Changed = ChangeStatus::UNCHANGED;
+
   // Look at all returned call sites.
   for (auto &It : ReturnedValues) {
     SmallPtrSet<ReturnInst *, 2> &ReturnInsts = It.second;
@@ -742,6 +745,8 @@ ChangeStatus AAReturnedValuesImpl::updat
     // Try to find a assumed unique return value for the called function.
     auto *RetCSAA = A.getAAFor<AAReturnedValuesImpl>(*this, *RV);
     if (!RetCSAA) {
+      if (!HasOverdefinedReturnedCalls)
+        Changed = ChangeStatus::CHANGED;
       HasOverdefinedReturnedCalls = true;
       LLVM_DEBUG(dbgs() << "[AAReturnedValues] Returned call site (" << *RV
                         << ") with " << (RetCSAA ? "invalid" : "no")
@@ -763,6 +768,8 @@ ChangeStatus AAReturnedValuesImpl::updat
     // If multiple, non-refinable values were found, there cannot be a unique
     // return value for the called function. The returned call is overdefined!
     if (!AssumedUniqueRV.getValue()) {
+      if (!HasOverdefinedReturnedCalls)
+        Changed = ChangeStatus::CHANGED;
       HasOverdefinedReturnedCalls = true;
       LLVM_DEBUG(dbgs() << "[AAReturnedValues] Returned call site has multiple "
                            "potentially returned values\n");
@@ -791,9 +798,6 @@ ChangeStatus AAReturnedValuesImpl::updat
       AddRVs[AssumedRetVal].insert(ReturnInsts.begin(), ReturnInsts.end());
   }
 
-  // Keep track of any change to trigger updates on dependent attributes.
-  ChangeStatus Changed = ChangeStatus::UNCHANGED;
-
   for (auto &It : AddRVs) {
     assert(!It.second.empty() && "Entry does not add anything.");
     auto &ReturnInsts = ReturnedValues[It.first];