JIT: Check for reachable preds in RBO (#95556)

Nothing guarantees that all preds are reachable, in which case the "dominates" query does not make sense.
dotnet · Dec 4, 2023 · 4bbf678 · 4bbf678
1 parent 2c48baf
commit 4bbf678
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/coreclr/jit/redundantbranchopts.cpp b/src/coreclr/jit/redundantbranchopts.cpp
@@ -818,7 +818,7 @@ bool Compiler::optJumpThreadCheck(BasicBlock* const block, BasicBlock* const dom
     {
         for (BasicBlock* const predBlock : block->PredBlocks())
         {
-            if (!fgSsaDomTree->Dominates(domBlock, predBlock))
+            if (m_dfs->Contains(predBlock) && !fgSsaDomTree->Dominates(domBlock, predBlock))
             {
                 JITDUMP("Dom " FMT_BB " is stale (does not dominate pred " FMT_BB "); no threading\n", domBlock->bbNum,
                         predBlock->bbNum);