Result = DAG.getNode(ISD::TokenFactor, SDLoc(N), MVT::Other, Ops);
}
- // Don't add users to work list.
- return CombineTo(N, Result, false);
+ // Add users to worklist if AA is enabled, since it may introduce
+ // a lot of new chained token factors while removing memory deps.
+ bool UseAA = CombinerAA.getNumOccurrences() > 0 ? CombinerAA
+ : DAG.getSubtarget().useAA();
+ return CombineTo(N, Result, UseAA /*add to worklist*/);
}
return Result;
// fold (fp_round (fp_round x)) -> (fp_round x)
if (N0.getOpcode() == ISD::FP_ROUND) {
- // This is a value preserving truncation if both round's are.
- bool IsTrunc = N->getConstantOperandVal(1) == 1 &&
- N0.getNode()->getConstantOperandVal(1) == 1;
- return DAG.getNode(ISD::FP_ROUND, SDLoc(N), VT, N0.getOperand(0),
- DAG.getIntPtrConstant(IsTrunc));
+ const bool NIsTrunc = N->getConstantOperandVal(1) == 1;
+ const bool N0IsTrunc = N0.getNode()->getConstantOperandVal(1) == 1;
+ // If the first fp_round isn't a value preserving truncation, it might
+ // introduce a tie in the second fp_round, that wouldn't occur in the
+ // single-step fp_round we want to fold to.
+ // In other words, double rounding isn't the same as rounding.
+ // Also, this is a value preserving truncation iff both fp_round's are.
+ if (DAG.getTarget().Options.UnsafeFPMath || N0IsTrunc)
+ return DAG.getNode(ISD::FP_ROUND, SDLoc(N), VT, N0.getOperand(0),
+ DAG.getIntPtrConstant(NIsTrunc && N0IsTrunc));
}
// fold (fp_round (copysign X, Y)) -> (copysign (fp_round X), Y)
if (NotMaskLZ == 64) return Result; // All zero mask.
// See if we have a continuous run of bits. If so, we have 0*1+0*
- if (CountTrailingOnes_64(NotMask >> NotMaskTZ)+NotMaskTZ+NotMaskLZ != 64)
+ if (countTrailingOnes(NotMask >> NotMaskTZ) + NotMaskTZ + NotMaskLZ != 64)
return Result;
// Adjust NotMaskLZ down to be from the actual size of the int instead of i64.