Fix store numbering

The load path needs to use the offset relative to the store's target location.
dotnet · Oct 21, 2022 · 44238c8 · 44238c8
1 parent 99ed47c
commit 44238c8
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/src/coreclr/jit/valuenum.cpp b/src/coreclr/jit/valuenum.cpp
@@ -4917,8 +4917,10 @@ void Compiler::fgValueNumberLocalStore(GenTree*             storeNode,
                     // Avoid redundant bitcasts for the common case of a full definition.
                     fieldStoreType = fieldVarDsc->TypeGet();
                 }
+
+                ssize_t      fieldValueOffset = max(0, fieldVarDsc->lvFldOffset - offset);
                 ValueNumPair fieldStoreValue =
-                    vnStore->VNPairForLoad(value, storeSize, fieldStoreType, offset, fieldStoreSize);
+                    vnStore->VNPairForLoad(value, storeSize, fieldStoreType, fieldValueOffset, fieldStoreSize);
 
                 processDef(fieldLclNum, lclDefNode->GetSsaNum(this, index), fieldStoreOffset, fieldStoreSize,
                            fieldStoreValue);