[llvm] r318757 - [RISCV][NFC] Clean up RISCVDAGToDAGISel::Select

[Alex Bradbury via llvm-commits]

Author: asb
Date: Tue Nov 21 04:00:19 2017
New Revision: 318757

URL: http://llvm.org/viewvc/llvm-project?rev=318757&view=rev
Log:
[RISCV][NFC] Clean up RISCVDAGToDAGISel::Select

As pointed out in post-commit review of r318738, `return ReplaceNode(..)` when 
both ReplaceNode and the current function return void is confusing. This patch 
moves to using a more obvious early return, and moves to just using an if to 
catch the one case we currently care about. A future patch that adds further 
custom instruction selection can introduce a switch.

Modified:
    llvm/trunk/lib/Target/RISCV/RISCVISelDAGToDAG.cpp

Modified: llvm/trunk/lib/Target/RISCV/RISCVISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/RISCV/RISCVISelDAGToDAG.cpp?rev=318757&r1=318756&r2=318757&view=diff
==============================================================================
--- llvm/trunk/lib/Target/RISCV/RISCVISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/RISCV/RISCVISelDAGToDAG.cpp Tue Nov 21 04:00:19 2017
@@ -65,21 +65,16 @@ void RISCVDAGToDAGISel::Select(SDNode *N
   // Instruction Selection not handled by the auto-generated tablegen selection
   // should be handled here.
   EVT VT = Node->getValueType(0);
-  switch (Opcode) {
-  case ISD::Constant:
-    if (VT == XLenVT) {
-      ConstantSDNode *ConstNode = cast<ConstantSDNode>(Node);
-      // Materialize zero constants as copies from X0. This allows the coalescer
-      // to propagate these into other instructions.
-      if (ConstNode->isNullValue()) {
-        SDValue New = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
-                                             SDLoc(Node), RISCV::X0, XLenVT);
-        return ReplaceNode(Node, New.getNode());
-      }
+  if (Opcode == ISD::Constant && VT == XLenVT) {
+    auto *ConstNode = cast<ConstantSDNode>(Node);
+    // Materialize zero constants as copies from X0. This allows the coalescer
+    // to propagate these into other instructions.
+    if (ConstNode->isNullValue()) {
+      SDValue New = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), SDLoc(Node),
+                                           RISCV::X0, XLenVT);
+      ReplaceNode(Node, New.getNode());
+      return;
     }
-    break;
-  default:
-    break;
   }
 
   // Select the default instruction.