Transforms/InstCombine/InstCombineAddSub.cpp

457   Value *Opnd1_1 = I1->getOperand(1);
468     if (Opnd0_0 == Opnd1_0 || Opnd0_0 == Opnd1_1)
470     else if (Opnd0_1 == Opnd1_0 || Opnd0_1 == Opnd1_1)
475       AddSub1 = (Factor == Opnd1_0) ? Opnd1_1 : Opnd1_0;
477   } else if (Opnd0_1 == Opnd1_1) {
515   FAddend Opnd0, Opnd1, Opnd0_0, Opnd0_1, Opnd1_0, Opnd1_1;
526   // Step 2: Expand the 2nd addend into Opnd1_0 and Opnd1_1.
528     Opnd1_ExpNum = Opnd1.drillAddendDownOneStep(Opnd1_0, Opnd1_1);
530   // Step 3: Try to optimize Opnd0_0 + Opnd0_1 + Opnd1_0 + Opnd1_1
538       AllOpnds.push_back(&Opnd1_1);
561   // step 4: Try to optimize Opnd0 + Opnd1_0 [+ Opnd1_1]
567       AllOpnds.push_back(&Opnd1_1);