From c77a5c21bbf061bdfdfa90a62aa60679c5810306 Mon Sep 17 00:00:00 2001 From: Nikita Popov Date: Thu, 7 Oct 2021 22:06:53 +0200 Subject: [PATCH] [BasicAA] Use base of decomposed GEP in recursive queries (NFC) DecompGEP.Base and UnderlyingV are currently always the same. However, logically DecompGEP.Base is the right value to use here, because the decomposed offset is relative to that base. --- llvm/lib/Analysis/BasicAliasAnalysis.cpp | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp index 6064bd6d995d..84e7683b9624 100644 --- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp +++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp @@ -1168,14 +1168,14 @@ AliasResult BasicAAResult::aliasGEP( // For GEPs with identical offsets, we can preserve the size and AAInfo // when performing the alias check on the underlying objects. if (DecompGEP1.Offset == 0 && DecompGEP1.VarIndices.empty()) - return getBestAAResults().alias( - MemoryLocation(UnderlyingV1, V1Size), - MemoryLocation(UnderlyingV2, V2Size), AAQI); + return getBestAAResults().alias(MemoryLocation(DecompGEP1.Base, V1Size), + MemoryLocation(DecompGEP2.Base, V2Size), + AAQI); // Do the base pointers alias? AliasResult BaseAlias = getBestAAResults().alias( - MemoryLocation::getBeforeOrAfter(UnderlyingV1), - MemoryLocation::getBeforeOrAfter(UnderlyingV2), AAQI); + MemoryLocation::getBeforeOrAfter(DecompGEP1.Base), + MemoryLocation::getBeforeOrAfter(DecompGEP2.Base), AAQI); // If we get a No or May, then return it immediately, no amount of analysis // will improve this situation.