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

2 files changed, 8 insertions, 4 deletions

diff --git a/lib/CodeGen/SelectionDAG/LegalizeTypes.h b/lib/CodeGen/SelectionDAG/LegalizeTypes.h
index 37f0e60087..20b7ce6b15 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeTypes.h
+++ b/lib/CodeGen/SelectionDAG/LegalizeTypes.h
@@ -634,7 +634,7 @@ private:
   SDValue WidenVecRes_InregOp(SDNode *N);
 
   // Widen Vector Operand.
-  bool WidenVectorOperand(SDNode *N, unsigned ResNo);
+  bool WidenVectorOperand(SDNode *N, unsigned OpNo);
   SDValue WidenVecOp_BITCAST(SDNode *N);
   SDValue WidenVecOp_CONCAT_VECTORS(SDNode *N);
   SDValue WidenVecOp_EXTRACT_VECTOR_ELT(SDNode *N);
diff --git a/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
index eca4d99098..d51a6eb192 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -2082,16 +2082,20 @@ SDValue DAGTypeLegalizer::WidenVecRes_VSETCC(SDNode *N) {
 //===----------------------------------------------------------------------===//
 // Widen Vector Operand
 //===----------------------------------------------------------------------===//
-bool DAGTypeLegalizer::WidenVectorOperand(SDNode *N, unsigned ResNo) {
-  DEBUG(dbgs() << "Widen node operand " << ResNo << ": ";
+bool DAGTypeLegalizer::WidenVectorOperand(SDNode *N, unsigned OpNo) {
+  DEBUG(dbgs() << "Widen node operand " << OpNo << ": ";
         N->dump(&DAG);
         dbgs() << "\n");
   SDValue Res = SDValue();
 
+  // See if the target wants to custom widen this node.
+  if (CustomLowerNode(N, N->getOperand(OpNo).getValueType(), false))
+    return false;
+
   switch (N->getOpcode()) {
   default:
 #ifndef NDEBUG
-    dbgs() << "WidenVectorOperand op #" << ResNo << ": ";
+    dbgs() << "WidenVectorOperand op #" << OpNo << ": ";
     N->dump(&DAG);
     dbgs() << "\n";
 #endif