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-rw-r--r--llvm/lib/Analysis/ValueTracking.cpp12
1 files changed, 0 insertions, 12 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 78ec220..16dd307 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -1240,18 +1240,6 @@ static void computeKnownBitsFromOperator(Operator *I, APInt &KnownZero,
KnownZero = APInt::getLowBitsSet(BitWidth,
std::min(KnownZero2.countTrailingOnes(),
KnownZero3.countTrailingOnes()));
-
- // If the operation is an addition that can't have signed overflow,
- // then the sign bit is known to be zero if both input sign bits
- // are zero. Similar for two negative inputs.
- if (Opcode == Instruction::Add &&
- cast<OverflowingBinaryOperator>(LU)->hasNoSignedWrap()) {
- if (KnownZero2.isNegative() && KnownZero3.isNegative())
- KnownZero.setBit(BitWidth-1);
- if (KnownOne2.isNegative() && KnownOne3.isNegative())
- KnownOne.setBit(BitWidth-1);
- }
-
break;
}
}