From 285d5e6b8b1ecc70c25468b6c7458d2adadeddf3 Mon Sep 17 00:00:00 2001
From: Craig Topper <craig.topper@gmail.com>
Date: Sat, 4 Jan 2020 17:03:33 -0800
Subject: [PATCH] [LegalizeVectorOps] Split most of ExpandStrictFPOp into a
 separate UnrollStrictFPOp method. Call that method from ExpandUINT_TO_FLOAT.

ExpandStrictFPOp calls ExpandUINT_TO_FLOAT. Previously, ExpandUINT_TO_FLOAT
returned SDValue() if it wasn't able to handle and needed to unroll.
Then ExpandStrictFPOp would detect his SDValue() and do the unroll.

After this change, ExpandUINT_TO_FLOAT will directly call
UnrollStrictFPOp and return the unrolled result.
---
 .../SelectionDAG/LegalizeVectorOps.cpp        | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp
index c4287b09780c..4127feda0e8f 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp
@@ -148,6 +148,8 @@ class VectorLegalizer {
   SDValue ExpandFixedPointMul(SDValue Op);
   SDValue ExpandStrictFPOp(SDValue Op);
 
+  SDValue UnrollStrictFPOp(SDValue Op);
+
   /// Implements vector promotion.
   ///
   /// This is essentially just bitcasting the operands to a different type and
@@ -1208,8 +1210,11 @@ SDValue VectorLegalizer::ExpandUINT_TO_FLOAT(SDValue Op) {
                          TargetLowering::Expand) ||
        (IsStrict && TLI.getOperationAction(ISD::STRICT_SINT_TO_FP, VT) ==
                         TargetLowering::Expand)) ||
-      TLI.getOperationAction(ISD::SRL, VT) == TargetLowering::Expand)
-    return IsStrict ? SDValue() : DAG.UnrollVectorOp(Op.getNode());
+      TLI.getOperationAction(ISD::SRL, VT) == TargetLowering::Expand) {
+    if (IsStrict)
+      return UnrollStrictFPOp(Op);
+    return DAG.UnrollVectorOp(Op.getNode());
+  }
 
   unsigned BW = VT.getScalarSizeInBits();
   assert((BW == 64 || BW == 32) &&
@@ -1386,11 +1391,13 @@ SDValue VectorLegalizer::ExpandFixedPointMul(SDValue Op) {
 }
 
 SDValue VectorLegalizer::ExpandStrictFPOp(SDValue Op) {
-  if (Op.getOpcode() == ISD::STRICT_UINT_TO_FP) {
-    if (SDValue Res = ExpandUINT_TO_FLOAT(Op))
-      return Res;
-  }
+  if (Op.getOpcode() == ISD::STRICT_UINT_TO_FP)
+    return ExpandUINT_TO_FLOAT(Op);
 
+  return UnrollStrictFPOp(Op);
+}
+
+SDValue VectorLegalizer::UnrollStrictFPOp(SDValue Op) {
   EVT VT = Op.getValue(0).getValueType();
   EVT EltVT = VT.getVectorElementType();
   unsigned NumElems = VT.getVectorNumElements();