Pass DebugLoc and SDLoc by const ref.

This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.

llvm-svn: 272512

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp b/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
index 8f0f4bed797..4448b0582ba 100644
--- a/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
@@ -441,7 +441,7 @@ void InstrEmitter::AddOperand(MachineInstrBuilder &MIB,
 }
 
 unsigned InstrEmitter::ConstrainForSubReg(unsigned VReg, unsigned SubIdx,
-                                          MVT VT, DebugLoc DL) {
+                                          MVT VT, const DebugLoc &DL) {
   const TargetRegisterClass *VRC = MRI->getRegClass(VReg);
   const TargetRegisterClass *RC = TRI->getSubClassWithSubReg(VRC, SubIdx);