Add alternative support for FP_ROUND from v2f32 to v2f64
- Due to the current matching vector elements constraints in ISD::FP_EXTEND,
rounding from v2f32 to v2f64 is scalarized. Add a customized v2f32 widening
to convert it into a target-specific X86ISD::VFPEXT to work around this
constraints. This patch also reverts a previous attempt to fix this issue by
recovering the scalarized ISD::FP_EXTEND pattern and thus significantly
reduces the overhead of supporting non-power-2 vector FP extend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165625 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 7e43e54..d551d9d 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -939,6 +939,8 @@
setOperationAction(ISD::FP_TO_SINT, MVT::v4i32, Legal);
setOperationAction(ISD::SINT_TO_FP, MVT::v4i32, Legal);
+ setOperationAction(ISD::FP_EXTEND, MVT::v2f32, Custom);
+
setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, Legal);
}
@@ -5161,86 +5163,6 @@
return SDValue();
}
-// LowerVectorFpExtend - Recognize the scalarized FP_EXTEND from v2f32 to v2f64
-// and convert it into X86ISD::VFPEXT due to the current ISD::FP_EXTEND has the
-// constraint of matching input/output vector elements.
-SDValue
-X86TargetLowering::LowerVectorFpExtend(SDValue &Op, SelectionDAG &DAG) const {
- DebugLoc DL = Op.getDebugLoc();
- SDNode *N = Op.getNode();
- EVT VT = Op.getValueType();
- unsigned NumElts = Op.getNumOperands();
-
- // Check supported types and sub-targets.
- //
- // Only v2f32 -> v2f64 needs special handling.
- if (VT != MVT::v2f64 || !Subtarget->hasSSE2())
- return SDValue();
-
- SDValue VecIn;
- EVT VecInVT;
- SmallVector<int, 8> Mask;
- EVT SrcVT = MVT::Other;
-
- // Check the patterns could be translated into X86vfpext.
- for (unsigned i = 0; i < NumElts; ++i) {
- SDValue In = N->getOperand(i);
- unsigned Opcode = In.getOpcode();
-
- // Skip if the element is undefined.
- if (Opcode == ISD::UNDEF) {
- Mask.push_back(-1);
- continue;
- }
-
- // Quit if one of the elements is not defined from 'fpext'.
- if (Opcode != ISD::FP_EXTEND)
- return SDValue();
-
- // Check how the source of 'fpext' is defined.
- SDValue L2In = In.getOperand(0);
- EVT L2InVT = L2In.getValueType();
-
- // Check the original type
- if (SrcVT == MVT::Other)
- SrcVT = L2InVT;
- else if (SrcVT != L2InVT) // Quit if non-homogenous typed.
- return SDValue();
-
- // Check whether the value being 'fpext'ed is extracted from the same
- // source.
- Opcode = L2In.getOpcode();
-
- // Quit if it's not extracted with a constant index.
- if (Opcode != ISD::EXTRACT_VECTOR_ELT ||
- !isa<ConstantSDNode>(L2In.getOperand(1)))
- return SDValue();
-
- SDValue ExtractedFromVec = L2In.getOperand(0);
-
- if (VecIn.getNode() == 0) {
- VecIn = ExtractedFromVec;
- VecInVT = ExtractedFromVec.getValueType();
- } else if (VecIn != ExtractedFromVec) // Quit if built from more than 1 vec.
- return SDValue();
-
- Mask.push_back(cast<ConstantSDNode>(L2In.getOperand(1))->getZExtValue());
- }
-
- // Quit if all operands of BUILD_VECTOR are undefined.
- if (!VecIn.getNode())
- return SDValue();
-
- // Fill the remaining mask as undef.
- for (unsigned i = NumElts; i < VecInVT.getVectorNumElements(); ++i)
- Mask.push_back(-1);
-
- return DAG.getNode(X86ISD::VFPEXT, DL, VT,
- DAG.getVectorShuffle(VecInVT, DL,
- VecIn, DAG.getUNDEF(VecInVT),
- &Mask[0]));
-}
-
SDValue
X86TargetLowering::LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const {
DebugLoc dl = Op.getDebugLoc();
@@ -5273,10 +5195,6 @@
if (Broadcast.getNode())
return Broadcast;
- SDValue FpExt = LowerVectorFpExtend(Op, DAG);
- if (FpExt.getNode())
- return FpExt;
-
unsigned EVTBits = ExtVT.getSizeInBits();
unsigned NumZero = 0;
@@ -8215,6 +8133,20 @@
return FIST;
}
+SDValue X86TargetLowering::lowerFP_EXTEND(SDValue Op,
+ SelectionDAG &DAG) const {
+ DebugLoc DL = Op.getDebugLoc();
+ EVT VT = Op.getValueType();
+ SDValue In = Op.getOperand(0);
+ EVT SVT = In.getValueType();
+
+ assert(SVT == MVT::v2f32 && "Only customize MVT::v2f32 type legalization!");
+
+ return DAG.getNode(X86ISD::VFPEXT, DL, VT,
+ DAG.getNode(ISD::CONCAT_VECTORS, DL, MVT::v4f32,
+ In, DAG.getUNDEF(SVT)));
+}
+
SDValue X86TargetLowering::LowerFABS(SDValue Op, SelectionDAG &DAG) const {
LLVMContext *Context = DAG.getContext();
DebugLoc dl = Op.getDebugLoc();
@@ -11407,6 +11339,7 @@
case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
+ case ISD::FP_EXTEND: return lowerFP_EXTEND(Op, DAG);
case ISD::FABS: return LowerFABS(Op, DAG);
case ISD::FNEG: return LowerFNEG(Op, DAG);
case ISD::FCOPYSIGN: return LowerFCOPYSIGN(Op, DAG);