In cases where a pointer value is an operand of a multiplication or

division operation, don't attempt to use the operation's value as
the base of a getelementptr. This fixes PR4271.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72422 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 3 deletions

diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp
index 191fcc02c4..6992b99880 100644
--- a/lib/Analysis/ScalarEvolutionExpander.cpp
+++ b/lib/Analysis/ScalarEvolutionExpander.cpp
@@ -448,9 +448,14 @@ Value *SCEVExpander::visitAddRecExpr(const SCEVAddRecExpr *S) {
       ExposePointerBase(Base, RestArray[0], SE);
       // If we found a pointer, expand the AddRec with a GEP.
       if (const PointerType *PTy = dyn_cast<PointerType>(Base->getType())) {
-        Value *StartV = expand(Base);
-        assert(StartV->getType() == PTy && "Pointer type mismatch for GEP!");
-        return expandAddToGEP(RestArray, RestArray+1, PTy, Ty, StartV);
+        // Make sure the Base isn't something exotic, such as a multiplied
+        // or divided pointer value. In those cases, the result type isn't
+        // actually a pointer type.
+        if (!isa<SCEVMulExpr>(Base) && !isa<SCEVUDivExpr>(Base)) {
+          Value *StartV = expand(Base);
+          assert(StartV->getType() == PTy && "Pointer type mismatch for GEP!");
+          return expandAddToGEP(RestArray, RestArray+1, PTy, Ty, StartV);
+        }
       }
     }