Add some debug output to SRETPromotion.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54464 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/IPO/StructRetPromotion.cpp b/lib/Transforms/IPO/StructRetPromotion.cpp
index aa749448509422412e36129e14331c94ab0a1f6a..314d1b987119dd9de0eea6a3fa0f7e538e06fb94 100644 (file)
--- a/lib/Transforms/IPO/StructRetPromotion.cpp
+++ b/lib/Transforms/IPO/StructRetPromotion.cpp
@@ -89,6 +89,8 @@ bool SRETPromotion::PromoteReturn(CallGraphNode *CGN) {
   if (F->arg_size() == 0 || !F->hasStructRetAttr() || F->doesNotReturn())
     return false;
 
+  DOUT << "SretPromotion: Looking at sret function " << F->getNameStart() << "\n";
+
   assert (F->getReturnType() == Type::VoidTy && "Invalid function return type");
   Function::arg_iterator AI = F->arg_begin();
   const llvm::PointerType *FArgType = dyn_cast<PointerType>(AI->getType());
@@ -99,10 +101,12 @@ bool SRETPromotion::PromoteReturn(CallGraphNode *CGN) {
 
   // Check if it is ok to perform this promotion.
   if (isSafeToUpdateAllCallers(F) == false) {
+    DOUT << "SretPromotion: Not all callers can be updated\n";
     NumRejectedSRETUses++;
     return false;
   }
 
+  DOUT << "SretPromotion: sret argument will be promoted\n";
   NumSRET++;
   // [1] Replace use of sret parameter 
   AllocaInst *TheAlloca = new AllocaInst (STy, NULL, "mrv",