From 80bdc967e946b5d68646ffdee857400f9a120cca Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Mon, 7 Sep 2009 22:44:55 +0000 Subject: [PATCH] Don't commit stores with addresses that have indices that are not compile-time constant integers or that are out of bounds for their corresponding static array types. These can cause aliasing that GlobalOpt assumes won't happen. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81165 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/IPO/GlobalOpt.cpp | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp index 86c5e291948..b995a3d2864 100644 --- a/lib/Transforms/IPO/GlobalOpt.cpp +++ b/lib/Transforms/IPO/GlobalOpt.cpp @@ -2044,6 +2044,27 @@ static bool isSimpleEnoughPointerToCommit(Constant *C, LLVMContext &Context) { // external globals. if (!GV->hasDefinitiveInitializer()) return false; + + gep_type_iterator GEPI = gep_type_begin(CE), E = gep_type_end(CE); + User::op_iterator OI = next(CE->op_begin()); + + // The first index must be zero. + ConstantInt *CI = dyn_cast(*OI); + if (!CI || !CI->isZero()) return false; + ++GEPI; + ++OI; + + // The remaining indices must be compile-time known integers within the + // bounds of the corresponding static array types. + for (; GEPI != E; ++GEPI, ++OI) { + CI = dyn_cast(*OI); + if (!CI) return false; + if (const ArrayType *ATy = dyn_cast(*GEPI)) + if (CI->getValue().getActiveBits() > 64 || + CI->getZExtValue() >= ATy->getNumElements()) + return false; + } + return ConstantFoldLoadThroughGEPConstantExpr(GV->getInitializer(), CE, Context); } -- 2.34.1