Implement bottom-up fast-isel. This has the advantage of not requiring

a separate DCE pass over MachineInstrs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107804 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
index 8c4211ab29..55171fca09 100644
--- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
@@ -78,6 +78,13 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf) {
   MF = &mf;
   RegInfo = &MF->getRegInfo();
 
+  // Check whether the function can return without sret-demotion.
+  SmallVector<ISD::OutputArg, 4> Outs;
+  GetReturnInfo(Fn->getReturnType(),
+                Fn->getAttributes().getRetAttributes(), Outs, TLI);
+  CanLowerReturn = TLI.CanLowerReturn(Fn->getCallingConv(), Fn->isVarArg(),
+                                      Outs, Fn->getContext());
+
   // Create a vreg for each argument register that is not dead and is used
   // outside of the entry block for the function.
   for (Function::const_arg_iterator AI = Fn->arg_begin(), E = Fn->arg_end();