Add a new optimization pass: Stack Coloring, that merges disjoint static allocations (allocas). Allocas are known to be
disjoint if they are marked by disjoint lifetime markers (@llvm.lifetime.XXX intrinsics).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163299 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/InstrEmitter.cpp b/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
index 46ddab0..6d2cdea 100644
--- a/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
+++ b/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
@@ -873,6 +873,17 @@
     break;
   }
 
+  case ISD::LIFETIME_START:
+  case ISD::LIFETIME_END: {
+    unsigned TarOp = (Node->getOpcode() == ISD::LIFETIME_START) ?
+    TargetOpcode::LIFETIME_START : TargetOpcode::LIFETIME_END;
+
+    FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(Node->getOperand(1));
+    BuildMI(*MBB, InsertPos, Node->getDebugLoc(), TII->get(TarOp))
+    .addFrameIndex(FI->getIndex());
+    break;
+  }
+
   case ISD::INLINEASM: {
     unsigned NumOps = Node->getNumOperands();
     if (Node->getOperand(NumOps-1).getValueType() == MVT::Glue)