[X86] LowerEXTRACT_VECTOR_ELT - pull out repeated getOperand() calls.…

… NFC. Also, cleanup LowerEXTRACT_VECTOR_ELT_SSE4 comments which had references to non-constant extraction indices.
llvm · Mar 13, 2020 · fe047fb · fe047fb
1 parent 7b74b0d
commit fe047fb
Showing 1 changed file with 9 additions and 14 deletions.
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -17821,14 +17821,16 @@ SDValue X86TargetLowering::LowerVSELECT(SDValue Op, SelectionDAG &DAG) const {
 
 static SDValue LowerEXTRACT_VECTOR_ELT_SSE4(SDValue Op, SelectionDAG &DAG) {
   MVT VT = Op.getSimpleValueType();
+  SDValue Vec = Op.getOperand(0);
+  SDValue Idx = Op.getOperand(1);
+  assert(isa<ConstantSDNode>(Idx) && "Constant index expected");
   SDLoc dl(Op);
 
-  if (!Op.getOperand(0).getSimpleValueType().is128BitVector())
+  if (!Vec.getSimpleValueType().is128BitVector())
     return SDValue();
 
   if (VT.getSizeInBits() == 8) {
-    SDValue Extract = DAG.getNode(X86ISD::PEXTRB, dl, MVT::i32,
-                                  Op.getOperand(0), Op.getOperand(1));
+    SDValue Extract = DAG.getNode(X86ISD::PEXTRB, dl, MVT::i32, Vec, Idx);
     return DAG.getNode(ISD::TRUNCATE, dl, VT, Extract);
   }
 
@@ -17841,22 +17843,17 @@ static SDValue LowerEXTRACT_VECTOR_ELT_SSE4(SDValue Op, SelectionDAG &DAG) {
     if (!Op.hasOneUse())
       return SDValue();
     SDNode *User = *Op.getNode()->use_begin();
-    if ((User->getOpcode() != ISD::STORE ||
-         isNullConstant(Op.getOperand(1))) &&
+    if ((User->getOpcode() != ISD::STORE || isNullConstant(Idx)) &&
         (User->getOpcode() != ISD::BITCAST ||
          User->getValueType(0) != MVT::i32))
       return SDValue();
     SDValue Extract = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, MVT::i32,
-                                  DAG.getBitcast(MVT::v4i32, Op.getOperand(0)),
-                                  Op.getOperand(1));
+                                  DAG.getBitcast(MVT::v4i32, Vec), Idx);
     return DAG.getBitcast(MVT::f32, Extract);
   }
 
-  if (VT == MVT::i32 || VT == MVT::i64) {
-    // ExtractPS/pextrq works with constant index.
-    if (isa<ConstantSDNode>(Op.getOperand(1)))
+  if (VT == MVT::i32 || VT == MVT::i64)
       return Op;
-  }
 
   return SDValue();
 }
@@ -17986,9 +17983,7 @@ X86TargetLowering::LowerEXTRACT_VECTOR_ELT(SDValue Op,
                          DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, MVT::i32,
                                      DAG.getBitcast(MVT::v4i32, Vec), Idx));
 
-    // Transform it so it match pextrw which produces a 32-bit result.
-    SDValue Extract = DAG.getNode(X86ISD::PEXTRW, dl, MVT::i32,
-                                  Op.getOperand(0), Op.getOperand(1));
+    SDValue Extract = DAG.getNode(X86ISD::PEXTRW, dl, MVT::i32, Vec, Idx);
     return DAG.getNode(ISD::TRUNCATE, dl, VT, Extract);
   }