[llvm] 14a49f5 - [DSE] Don't check getUnderlyingObject() return value (NFC)

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2021-09-26T18:01:26+02:00
New Revision: 14a49f5840a15791e7452200832a51bd11620df6

URL: https://github.com/llvm/llvm-project/commit/14a49f5840a15791e7452200832a51bd11620df6
DIFF: https://github.com/llvm/llvm-project/commit/14a49f5840a15791e7452200832a51bd11620df6.diff

LOG: [DSE] Don't check getUnderlyingObject() return value (NFC)

getUnderlyingObject() never returns null. It will simply return
something that is not the "root" underlying object.

Also drop a stale comment.

Added: 
    

Modified: 
    llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
index 08b940d3f5a0..769ca03e01c3 100644
--- a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -1279,10 +1279,6 @@ struct DSEState {
       if (CB->onlyAccessesInaccessibleMemory())
         return false;
 
-    // NOTE: For calls, the number of stores removed could be slightly improved
-    // by using AA.callCapturesBefore(UseInst, DefLoc, &DT), but that showed to
-    // be expensive compared to the benefits in practice. For now, avoid more
-    // expensive analysis to limit compile-time.
     return isRefSet(BatchAA.getModRefInfo(UseInst, DefLoc));
   }
 
@@ -1793,7 +1789,7 @@ struct DSEState {
       // uncommon. If it turns out to be important, we can use
       // getUnderlyingObjects here instead.
       const Value *UO = getUnderlyingObject(DefLoc->Ptr);
-      if (!UO || !isInvisibleToCallerAfterRet(UO))
+      if (!isInvisibleToCallerAfterRet(UO))
         continue;
 
       if (isWriteAtEndOfFunction(Def)) {
@@ -1965,9 +1961,7 @@ static bool eliminateDeadStores(Function &F, AliasAnalysis &AA, MemorySSA &MSSA,
     unsigned PartialLimit = MemorySSAPartialStoreLimit;
     // Worklist of MemoryAccesses that may be killed by KillingDef.
     SetVector<MemoryAccess *> ToCheck;
-
-    if (KillingUndObj)
-      ToCheck.insert(KillingDef->getDefiningAccess());
+    ToCheck.insert(KillingDef->getDefiningAccess());
 
     bool Shortend = false;
     bool IsMemTerm = State.isMemTerminatorInst(KillingI);