ArgumentPromotion: Remove ancient workaround for a bug in the C backend.

Fun fact: The CBE learned how to deal with this situation before it was removed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164918 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/IPO/ArgumentPromotion.cpp b/lib/Transforms/IPO/ArgumentPromotion.cpp
index b94dd69deb75d60471545e19b9b745010fb7fb1d..10f5b6e6583e11cc4212fc124cfa6d851bcab77a 100644 (file)
--- a/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -592,14 +592,6 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F,
 
   Type *RetTy = FTy->getReturnType();
 
-  // Work around LLVM bug PR56: the CWriter cannot emit varargs functions which
-  // have zero fixed arguments.
-  bool ExtraArgHack = false;
-  if (Params.empty() && FTy->isVarArg()) {
-    ExtraArgHack = true;
-    Params.push_back(Type::getInt32Ty(F->getContext()));
-  }
-
   // Construct the new function type using the new arguments.
   FunctionType *NFTy = FunctionType::get(RetTy, Params, FTy->isVarArg());
 
@@ -711,9 +703,6 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F,
         }
       }
 
-    if (ExtraArgHack)
-      Args.push_back(Constant::getNullValue(Type::getInt32Ty(F->getContext())));
-
     // Push any varargs arguments on the list.
     for (; AI != CS.arg_end(); ++AI, ++ArgIndex) {
       Args.push_back(*AI);
@@ -870,16 +859,9 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F,
     }
 
     // Increment I2 past all of the arguments added for this promoted pointer.
-    for (unsigned i = 0, e = ArgIndices.size(); i != e; ++i)
-      ++I2;
+    std::advance(I2, ArgIndices.size());
   }
 
-  // Notify the alias analysis implementation that we inserted a new argument.
-  if (ExtraArgHack)
-    AA.copyValue(Constant::getNullValue(Type::getInt32Ty(F->getContext())), 
-                 NF->arg_begin());
-
-
   // Tell the alias analysis that the old function is about to disappear.
   AA.replaceWithNewValue(F, NF);