#define DEBUG_TYPE "deadargelim"
#include "llvm/Transforms/IPO.h"
-#include "llvm/Module.h"
-#include "llvm/Pass.h"
-#include "llvm/DerivedTypes.h"
+#include "llvm/CallingConv.h"
#include "llvm/Constant.h"
+#include "llvm/DerivedTypes.h"
#include "llvm/Instructions.h"
+#include "llvm/Module.h"
+#include "llvm/Pass.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/Debug.h"
#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/iterator"
#include <iostream>
#include <set>
using namespace llvm;
// (used in a computation), MaybeLive (only passed as an argument to a call), or
// Dead (not used).
DAE::Liveness DAE::getArgumentLiveness(const Argument &A) {
- if (A.use_empty()) return Dead; // First check, directly dead?
+ // If this is the return value of a csret function, it's not really dead.
+ if (A.getParent()->getCallingConv() == CallingConv::CSRet &&
+ &*A.getParent()->arg_begin() == &A)
+ return Live;
+
+ if (A.use_empty()) // First check, directly dead?
+ return Dead;
// Scan through all of the uses, looking for non-argument passing uses.
for (Value::use_const_iterator I = A.use_begin(), E = A.use_end(); I!=E;++I) {