when inserting a dummy argument to work-around the CBE not supporting
zero arg vararg functions, pass undef instead of 'int 0', which is cheaper.
llvm-svn: 32634
diff --git a/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp b/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp
index d3326ac..dbcc501 100644
--- a/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp
+++ b/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp
@@ -499,8 +499,6 @@
// Work around LLVM bug PR56: the CWriter cannot emit varargs functions which
// have zero fixed arguments.
//
- // FIXME: once this bug is fixed in the CWriter, this hack should be removed.
- //
bool ExtraArgHack = false;
if (Params.empty() && FTy->isVarArg()) {
ExtraArgHack = true;
@@ -530,7 +528,7 @@
Args.push_back(*AI);
if (ExtraArgHack)
- Args.push_back(Constant::getNullValue(Type::IntTy));
+ Args.push_back(UndefValue::get(Type::IntTy));
// Push any varargs arguments on the list
for (; AI != CS.arg_end(); ++AI)