[llvm] [GVN] MemorySSA for GVN: eliminate redundant loads via MemorySSA (PR #152859)

[Antonio Frighetto via llvm-commits]

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@@ -887,7 +892,8 @@ PreservedAnalyses GVNPass::run(Function &F, FunctionAnalysisManager &AM) {
   auto *MemDep =
       isMemDepEnabled() ? &AM.getResult<MemoryDependenceAnalysis>(F) : nullptr;
   auto &LI = AM.getResult<LoopAnalysis>(F);
-  auto *MSSA = AM.getCachedResult<MemorySSAAnalysis>(F);
+  auto *MSSA =
+      isMemorySSAEnabled() ? AM.getCachedResult<MemorySSAAnalysis>(F) : nullptr;
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antoniofrighetto wrote:

Should avoid retrieving cached results (and thus computing MemorySSAUpdater) if MemorySSA is not enabled (missed from the initial patch, realized while running tests, may happen that both MD and MSSAU exist, as of now).

https://github.com/llvm/llvm-project/pull/152859