Recommit : Use the basic cost if a GEP is not used as addressing mode

Recommitting r314517 with the fix for handling ConstantExpr.

Original commit message:
  Currently, getGEPCost() returns TCC_FREE whenever a GEP is a legal addressing
  mode in the target. However, since it doesn't check its actual users, it will
  return FREE even in cases where the GEP cannot be folded away as a part of
  actual addressing mode. For example, if an user of the GEP is a call
  instruction taking the GEP as a parameter, then the GEP may not be folded in
  isel.

llvm-svn: 314923

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/StraightLineStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/StraightLineStrengthReduce.cpp
index 8b8d6590aa6..3f93eaecc5d 100644
--- a/llvm/lib/Transforms/Scalar/StraightLineStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/StraightLineStrengthReduce.cpp
@@ -239,7 +239,7 @@ static bool isGEPFoldable(GetElementPtrInst *GEP,
   SmallVector<const Value*, 4> Indices;
   for (auto I = GEP->idx_begin(); I != GEP->idx_end(); ++I)
     Indices.push_back(*I);
-  return TTI->getGEPCost(GEP->getSourceElementType(), GEP->getPointerOperand(),
+  return TTI->getGEPCost(cast<GEPOperator>(GEP),
                          Indices) == TargetTransformInfo::TCC_Free;
 }