Pull a few more simplifications out of instcombine (there are still
plenty left though!), in particular for multiplication.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122330 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
index 6bce6a2..a2fe0cf 100644
--- a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -14,6 +14,7 @@
#include "InstCombine.h"
#include "llvm/IntrinsicInst.h"
+#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Support/PatternMatch.h"
using namespace llvm;
using namespace PatternMatch;
@@ -50,8 +51,8 @@
bool Changed = SimplifyAssociativeOrCommutative(I);
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
- if (isa<UndefValue>(Op1)) // undef * X -> 0
- return ReplaceInstUsesWith(I, Constant::getNullValue(I.getType()));
+ if (Value *V = SimplifyMulInst(Op0, Op1, TD))
+ return ReplaceInstUsesWith(I, V);
// Simplify mul instructions with a constant RHS.
if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
@@ -64,10 +65,6 @@
return BinaryOperator::CreateMul(SI->getOperand(0),
ConstantExpr::getShl(CI, ShOp));
- if (CI->isZero())
- return ReplaceInstUsesWith(I, Op1C); // 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());