Instead of a vector load, shuffle and then extract an element. Load the element from address with an offset.
pshufd $1, (%rdi), %xmm0
movd %xmm0, %eax
=>
movl 4(%rdi), %eax
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51026 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 806b626..4cc3f27 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -6182,26 +6182,6 @@
}
}
-/// getShuffleScalarElt - Returns the scalar element that will make up the ith
-/// element of the result of the vector shuffle.
-static SDOperand getShuffleScalarElt(SDNode *N, unsigned i, SelectionDAG &DAG) {
- MVT::ValueType VT = N->getValueType(0);
- SDOperand PermMask = N->getOperand(2);
- unsigned NumElems = PermMask.getNumOperands();
- SDOperand V = (i < NumElems) ? N->getOperand(0) : N->getOperand(1);
- i %= NumElems;
- if (V.getOpcode() == ISD::SCALAR_TO_VECTOR) {
- return (i == 0)
- ? V.getOperand(0) : DAG.getNode(ISD::UNDEF, MVT::getVectorElementType(VT));
- } else if (V.getOpcode() == ISD::VECTOR_SHUFFLE) {
- SDOperand Idx = PermMask.getOperand(i);
- if (Idx.getOpcode() == ISD::UNDEF)
- return DAG.getNode(ISD::UNDEF, MVT::getVectorElementType(VT));
- return getShuffleScalarElt(V.Val,cast<ConstantSDNode>(Idx)->getValue(),DAG);
- }
- return SDOperand();
-}
-
/// isGAPlusOffset - Returns true (and the GlobalValue and the offset) if the
/// node is a GlobalAddress + offset.
bool X86TargetLowering::isGAPlusOffset(SDNode *N,
@@ -6240,7 +6220,7 @@
}
unsigned Index = cast<ConstantSDNode>(Idx)->getValue();
- SDOperand Elt = getShuffleScalarElt(N, Index, DAG);
+ SDOperand Elt = DAG.getShuffleScalarElt(N, Index);
if (!Elt.Val ||
(Elt.getOpcode() != ISD::UNDEF && !ISD::isNON_EXTLoad(Elt.Val)))
return false;