Changes in directory llvm/lib/Transforms/Scalar:
InstructionCombining.cpp updated: 1.718 -> 1.719 --- Log message: simplify (x+c)^signbit as (x+c+signbit), pointed out by PR1288: http://llvm.org/PR1288 . This implements test/Transforms/InstCombine/xor.ll:test28 --- Diffs of the changes: (+7 -1) InstructionCombining.cpp | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletion(-) Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.718 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.719 --- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.718 Sun Apr 1 15:57:36 2007 +++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp Mon Apr 2 00:36:22 2007 @@ -4005,7 +4005,7 @@ return BinaryOperator::createOr(Op0NotVal, NotY); } } - + if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1))) if (Op0I->getOpcode() == Instruction::Add) { // ~(X-c) --> (-c-1)-X @@ -4015,6 +4015,12 @@ ConstantExpr::getSub(NegOp0CI, ConstantInt::get(I.getType(), 1)), Op0I->getOperand(0)); + } else if (RHS->getValue().isMinSignedValue()) { + // (X + C) ^ signbit -> (X + C + signbit) + Constant *C = ConstantInt::get(RHS->getValue() + Op0CI->getValue()); + return BinaryOperator::createAdd(Op0I->getOperand(0), C); + + } } else if (Op0I->getOpcode() == Instruction::Or) { // (X|C1)^C2 -> X^(C1|C2) iff X&~C1 == 0 _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
