diff options
Diffstat (limited to 'llvm/lib/Analysis')
| -rw-r--r-- | llvm/lib/Analysis/ScalarEvolutionExpander.cpp | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/llvm/lib/Analysis/ScalarEvolutionExpander.cpp b/llvm/lib/Analysis/ScalarEvolutionExpander.cpp index 939907ce1b5..78bb0649f8c 100644 --- a/llvm/lib/Analysis/ScalarEvolutionExpander.cpp +++ b/llvm/lib/Analysis/ScalarEvolutionExpander.cpp @@ -2070,10 +2070,13 @@ bool SCEVExpander::isHighCostExpansionHelper( if (auto *UDivExpr = dyn_cast<SCEVUDivExpr>(S)) { // If the divisor is a power of two and the SCEV type fits in a native - // integer, consider the division cheap irrespective of whether it occurs in - // the user code since it can be lowered into a right shift. + // integer (and the LHS not expensive), consider the division cheap + // irrespective of whether it occurs in the user code since it can be + // lowered into a right shift. if (auto *SC = dyn_cast<SCEVConstant>(UDivExpr->getRHS())) if (SC->getAPInt().isPowerOf2()) { + if (isHighCostExpansionHelper(UDivExpr->getLHS(), L, At, Processed)) + return true; const DataLayout &DL = L->getHeader()->getParent()->getParent()->getDataLayout(); unsigned Width = cast<IntegerType>(UDivExpr->getType())->getBitWidth(); |
