Add a couple of missed optimizations on integer vectors. Multiply and divide
by 1, as well as multiply by -1.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60182 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 5631bd0..661b047 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -2576,12 +2576,21 @@
} else if (isa<VectorType>(Op1->getType())) {
if (isa<ConstantAggregateZero>(Op1))
return ReplaceInstUsesWith(I, Op1);
-
- // As above, vector X*splat(1.0) -> X in all defined cases.
- if (ConstantVector *Op1V = dyn_cast<ConstantVector>(Op1))
- if (ConstantFP *F = dyn_cast_or_null<ConstantFP>(Op1V->getSplatValue()))
- if (F->isExactlyValue(1.0))
- return ReplaceInstUsesWith(I, Op0);
+
+ if (ConstantVector *Op1V = dyn_cast<ConstantVector>(Op1)) {
+ if (Op1V->isAllOnesValue()) // X * -1 == 0 - X
+ return BinaryOperator::CreateNeg(Op0, I.getName());
+
+ // As above, vector X*splat(1.0) -> X in all defined cases.
+ if (Constant *Splat = Op1V->getSplatValue()) {
+ if (ConstantFP *F = dyn_cast<ConstantFP>(Splat))
+ if (F->isExactlyValue(1.0))
+ return ReplaceInstUsesWith(I, Op0);
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(Splat))
+ if (CI->equalsInt(1))
+ return ReplaceInstUsesWith(I, Op0);
+ }
+ }
}
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0))
@@ -2856,6 +2865,13 @@
if (I.getType() == Type::Int1Ty)
return ReplaceInstUsesWith(I, Op0);
+ if (ConstantVector *Op1V = dyn_cast<ConstantVector>(Op1)) {
+ if (ConstantInt *X = cast_or_null<ConstantInt>(Op1V->getSplatValue()))
+ // div X, 1 == X
+ if (X->isOne())
+ return ReplaceInstUsesWith(I, Op0);
+ }
+
return 0;
}