[llvm-commits] CVS: llvm/lib/Transforms/Scalar/InstructionCombining.cpp

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.137 -> 1.138

---
Log message:

Implement InstCombine/xor.ll:test(15|16)


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Diffs of the changes:  (+8 -1)

Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.137 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.138
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.137	Sun Nov  2 23:17:03 2003
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Tue Nov  4 17:37:10 2003
@@ -1002,7 +1002,14 @@
                                  SCI->getOperand(0), SCI->getOperand(1));
           
       if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1)))
-        if (Op0I->getOpcode() == Instruction::And) {
+        if (Op0I->getOpcode() == Instruction::Add) {
+          // ~(X-c) --> (-c-1)-X
+          if (RHS->isAllOnesValue()) 
+            return BinaryOperator::create(Instruction::Sub,
+                                          *-*Op0CI -
+                                              *ConstantInt::get(I.getType(), 1),
+                                          Op0I->getOperand(0));
+        } else if (Op0I->getOpcode() == Instruction::And) {
           // (X & C1) ^ C2 --> (X & C1) | C2 iff (C1&C2) == 0
           if ((*RHS & *Op0CI)->isNullValue())
             return BinaryOperator::create(Instruction::Or, Op0, RHS);