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

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.447 -> 1.448
---
Log message:

Canonicalize (X+C1)*C2 -> X*C2+C1*C2
This implements Transforms/InstCombine/add.ll:test31


---
Diffs of the changes:  (+13 -0)

 InstructionCombining.cpp |   13 +++++++++++++
 1 files changed, 13 insertions(+)


Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.447 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.448
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.447	Thu Mar  2 19:34:17 2006
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Sat Mar  4 00:04:02 2006
@@ -1622,6 +1622,19 @@
       if (Op1F->getValue() == 1.0)
         return ReplaceInstUsesWith(I, Op0);  // Eliminate 'mul double %X, 1.0'
     }
+    
+    if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0))
+      if (Op0I->getOpcode() == Instruction::Add && Op0I->hasOneUse() &&
+          isa<ConstantInt>(Op0I->getOperand(1))) {
+        // Canonicalize (X+C1)*C2 -> X*C2+C1*C2.
+        Instruction *Add = BinaryOperator::createMul(Op0I->getOperand(0),
+                                                     Op1, "tmp");
+        InsertNewInstBefore(Add, I);
+        Value *C1C2 = ConstantExpr::getMul(Op1, 
+                                           cast<Constant>(Op0I->getOperand(1)));
+        return BinaryOperator::createAdd(Add, C1C2);
+        
+      }
 
     // Try to fold constant mul into select arguments.
     if (SelectInst *SI = dyn_cast<SelectInst>(Op0))