[Openmp-commits] [PATCH] D106085: [OpenMP] Fix carefully track SPMDCompatibilityTracker

[Johannes Doerfert via Phabricator via Openmp-commits]

jdoerfert created this revision.
jdoerfert added reviewers: tianshilei1992, ggeorgakoudis, jhuber6.
Herald added subscribers: ormris, guansong, bollu, hiraditya, yaxunl.
jdoerfert requested review of this revision.
Herald added subscribers: llvm-commits, sstefan1.
Herald added a project: LLVM.

We did not properly use SPMDCompatibilityTracker in various places.
This patch makes sure we look at the validity properly and also fix
the state if we can.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D106085

Files:
  llvm/lib/Transforms/IPO/OpenMPOpt.cpp


Index: llvm/lib/Transforms/IPO/OpenMPOpt.cpp
===================================================================
--- llvm/lib/Transforms/IPO/OpenMPOpt.cpp
+++ llvm/lib/Transforms/IPO/OpenMPOpt.cpp
@@ -2793,7 +2793,7 @@
       // __kmpc_target_init or
       // __kmpc_target_deinit call. We will answer this one with the internal
       // state.
-      if (!isValidState())
+      if (!SPMDCompatibilityTracker.isValidState())
         return nullptr;
       if (!SPMDCompatibilityTracker.isAtFixpoint()) {
         if (AA)
@@ -3209,17 +3209,19 @@
     };
 
     bool UsedAssumedInformationInCheckRWInst = false;
-    if (!A.checkForAllReadWriteInstructions(
-            CheckRWInst, *this, UsedAssumedInformationInCheckRWInst))
-      SPMDCompatibilityTracker.indicatePessimisticFixpoint();
+    if (!SPMDCompatibilityTracker.isAtFixpoint())
+      if (!A.checkForAllReadWriteInstructions(
+              CheckRWInst, *this, UsedAssumedInformationInCheckRWInst))
+        SPMDCompatibilityTracker.indicatePessimisticFixpoint();
 
     // Callback to check a call instruction.
+    bool AllSPMDStatesWereFixed = true;
     auto CheckCallInst = [&](Instruction &I) {
       auto &CB = cast<CallBase>(I);
       auto &CBAA = A.getAAFor<AAKernelInfo>(
           *this, IRPosition::callsite_function(CB), DepClassTy::OPTIONAL);
-      if (CBAA.getState().isValidState())
-        getState() ^= CBAA.getState();
+      getState() ^= CBAA.getState();
+      AllSPMDStatesWereFixed &= CBAA.SPMDCompatibilityTracker.isAtFixpoint();
       return true;
     };
 
@@ -3228,6 +3230,12 @@
             CheckCallInst, *this, UsedAssumedInformationInCheckCallInst))
       return indicatePessimisticFixpoint();
 
+    // If we haven't used any assumed information for the SPMD state we can fix
+    // it.
+    if (!UsedAssumedInformationInCheckRWInst &&
+        !UsedAssumedInformationInCheckCallInst && AllSPMDStatesWereFixed)
+      SPMDCompatibilityTracker.indicateOptimisticFixpoint();
+
     return StateBefore == getState() ? ChangeStatus::UNCHANGED
                                      : ChangeStatus::CHANGED;
   }


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D106085.359059.patch
Type: text/x-patch
Size: 2115 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/openmp-commits/attachments/20210715/af1f198c/attachment-0001.bin>