[DAGCombiner] Add support for TRUNCATE + FP_EXTEND vector constant folding
This patch adds supports for the vector constant folding of TRUNCATE and FP_EXTEND instructions and tidies up the SINT_TO_FP and UINT_TO_FP instructions to match.
It also moves the vector constant folding for the FNEG and FABS instructions to use the DAG.getNode() functionality like the other unary instructions.
Differential Revision: http://reviews.llvm.org/D8593
llvm-svn: 233224
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index eef07d9..b52f648 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -196,6 +196,22 @@
return true;
}
+/// \brief Return true if the specified node is a BUILD_VECTOR node of
+/// all ConstantFPSDNode or undef.
+bool ISD::isBuildVectorOfConstantFPSDNodes(const SDNode *N) {
+ if (N->getOpcode() != ISD::BUILD_VECTOR)
+ return false;
+
+ for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
+ SDValue Op = N->getOperand(i);
+ if (Op.getOpcode() == ISD::UNDEF)
+ continue;
+ if (!isa<ConstantFPSDNode>(Op))
+ return false;
+ }
+ return true;
+}
+
/// isScalarToVector - Return true if the specified node is a
/// ISD::SCALAR_TO_VECTOR node or a BUILD_VECTOR node where only the low
/// element is not an undef.
@@ -2827,7 +2843,7 @@
}
}
- // Constant fold unary operations with a vector integer operand.
+ // Constant fold unary operations with a vector integer or float operand.
if (BuildVectorSDNode *BV = dyn_cast<BuildVectorSDNode>(Operand.getNode())) {
if (BV->isConstant()) {
switch (Opcode) {
@@ -2835,6 +2851,10 @@
// FIXME: Entirely reasonable to perform folding of other unary
// operations here as the need arises.
break;
+ case ISD::FNEG:
+ case ISD::FABS:
+ case ISD::FP_EXTEND:
+ case ISD::TRUNCATE:
case ISD::UINT_TO_FP:
case ISD::SINT_TO_FP: {
// Let the above scalar folding handle the folding of each element.
@@ -2842,9 +2862,14 @@
for (int i = 0, e = VT.getVectorNumElements(); i != e; ++i) {
SDValue OpN = BV->getOperand(i);
OpN = getNode(Opcode, DL, VT.getVectorElementType(), OpN);
+ if (OpN.getOpcode() != ISD::UNDEF &&
+ OpN.getOpcode() != ISD::Constant &&
+ OpN.getOpcode() != ISD::ConstantFP)
+ break;
Ops.push_back(OpN);
}
- return getNode(ISD::BUILD_VECTOR, DL, VT, Ops);
+ if (Ops.size() == VT.getVectorNumElements())
+ return getNode(ISD::BUILD_VECTOR, DL, VT, Ops);
}
}
}