Factor out the code for checking that all indices in a getelementptr are

within the notional bounds of the static type of the getelementptr (which
is not the same as "inbounds") from GlobalOpt into a utility routine,
and use it in ConstantFold.cpp to check whether there are any mis-behaved
indices.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81478 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 15 deletions

diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp
index b995a3d..63bc03d 100644
--- a/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/lib/Transforms/IPO/GlobalOpt.cpp
@@ -2045,25 +2045,14 @@ static bool isSimpleEnoughPointerToCommit(Constant *C, LLVMContext &Context) {
       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<ConstantInt>(*OI);
+      ConstantInt *CI = dyn_cast<ConstantInt>(*next(CE->op_begin()));
       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<ConstantInt>(*OI);
-        if (!CI) return false;
-        if (const ArrayType *ATy = dyn_cast<ArrayType>(*GEPI))
-          if (CI->getValue().getActiveBits() > 64 ||
-              CI->getZExtValue() >= ATy->getNumElements())
-            return false;
-      }
+      // notional bounds of the corresponding static array types.
+      if (!CE->isGEPWithNoNotionalOverIndexing())
+        return false;
 
       return ConstantFoldLoadThroughGEPConstantExpr(GV->getInitializer(), CE,
                                                     Context);