aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--lib/Transforms/Scalar/LoopStrengthReduce.cpp10
1 files changed, 8 insertions, 2 deletions
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index b6ef718ce1..11f2187934 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -2012,8 +2012,14 @@ void LSRInstance::GenerateCombinations(LSRUse &LU, unsigned LUIdx,
F.BaseRegs.push_back(BaseReg);
}
if (Ops.size() > 1) {
- F.BaseRegs.push_back(SE.getAddExpr(Ops));
- (void)InsertFormula(LU, LUIdx, F);
+ const SCEV *Sum = SE.getAddExpr(Ops);
+ // TODO: If Sum is zero, it probably means ScalarEvolution missed an
+ // opportunity to fold something. For now, just ignore such cases
+ // rather than procede with zero in a register.
+ if (!Sum->isZero()) {
+ F.BaseRegs.push_back(Sum);
+ (void)InsertFormula(LU, LUIdx, F);
+ }
}
}