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

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.118 -> 1.119

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Log message:

Simplify code
Implement InstCombine/mul.ll:test9


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Diffs of the changes:

Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.118 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.119
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.118	Wed Sep 10 00:29:03 2003
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Thu Sep 11 17:24:54 2003
@@ -527,17 +527,14 @@
             return BinaryOperator::create(Instruction::Mul, SI->getOperand(0),
                                           *CI << *ShOp);
 
-      const Type *Ty = CI->getType();
-      int64_t Val = (int64_t)cast<ConstantInt>(CI)->getRawValue();
-      switch (Val) {
-      case -1:                               // X * -1 -> -X
+      if (CI->isNullValue())
+        return ReplaceInstUsesWith(I, Op1);  // X * 0  == 0
+      if (CI->equalsInt(1))                  // X * 1  == X
+        return ReplaceInstUsesWith(I, Op0);
+      if (CI->isAllOnesValue())              // X * -1 == 0 - X
         return BinaryOperator::createNeg(Op0, I.getName());
-      case 0:
-        return ReplaceInstUsesWith(I, Op1);  // Eliminate 'mul double %X, 0'
-      case 1:
-        return ReplaceInstUsesWith(I, Op0);  // Eliminate 'mul int %X, 1'
-      }
 
+      int64_t Val = (int64_t)cast<ConstantInt>(CI)->getRawValue();
       if (uint64_t C = Log2(Val))            // Replace X*(2^C) with X << C
         return new ShiftInst(Instruction::Shl, Op0,
                              ConstantUInt::get(Type::UByteTy, C));