commit 4dd569c7cc3db627ecf14a6f91db3c21b537d20a
author Florian Hahn <florian.hahn@arm.com> Wed Jun 13 20:59:53 2018 +0000
committer Florian Hahn <florian.hahn@arm.com> Wed Jun 13 20:59:53 2018 +0000
tree 8c565a56bb411125101b486bf0940a6b6ec9d615
parent 9218a37a658f45830ed9026c7653401ad431c04c

[TableGen] Make getOnlyTree return a const ref (NFC)

This avoids some unnecessary copies of shared_ptrs.
Those changes were suggested post-commit for D47463.

llvm-svn: 334656

llvm/utils/TableGen/CodeGenDAGPatterns.cpp

diff --git a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
index 998cf33..f1cde80 100644
--- a/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/llvm/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -4010,7 +4010,7 @@
                                   InstResults, InstImpResults);
 
     // Promote the xform function to be an explicit node if set.
-    TreePatternNodePtr DstPattern = Result.getOnlyTree();
+    const TreePatternNodePtr &DstPattern = Result.getOnlyTree();
     std::vector<TreePatternNodePtr> ResultNodeOperands;
     for (unsigned ii = 0, ee = DstPattern->getNumChildren(); ii != ee; ++ii) {
       TreePatternNodePtr OpNode = DstPattern->getChildShared(ii);
@@ -4023,16 +4023,18 @@
       }
       ResultNodeOperands.push_back(OpNode);
     }
-    DstPattern = Result.getOnlyTree();
-    if (!DstPattern->isLeaf())
-      DstPattern = std::make_shared<TreePatternNode>(DstPattern->getOperator(),
-                                                     ResultNodeOperands,
-                                                     DstPattern->getNumTypes());
+
+    TreePatternNodePtr DstShared =
+        DstPattern->isLeaf()
+            ? DstPattern
+            : std::make_shared<TreePatternNode>(DstPattern->getOperator(),
+                                                ResultNodeOperands,
+                                                DstPattern->getNumTypes());
 
     for (unsigned i = 0, e = Result.getOnlyTree()->getNumTypes(); i != e; ++i)
-      DstPattern->setType(i, Result.getOnlyTree()->getExtType(i));
+      DstShared->setType(i, Result.getOnlyTree()->getExtType(i));
 
-    TreePattern Temp(Result.getRecord(), DstPattern, false, *this);
+    TreePattern Temp(Result.getRecord(), DstShared, false, *this);
     Temp.InferAllTypes();
 
     // A pattern may end up with an "impossible" type, i.e. a situation