If there are no machine instructions emitted for a function, then insert

a "nop" instruction so that we don't have the function's label associated
with something that it's not supposed to be associated with.

llvm-svn: 46394

1 files changed, 1 insertions, 14 deletions

diff --git a/llvm/lib/Transforms/Scalar/SimplifyCFG.cpp b/llvm/lib/Transforms/Scalar/SimplifyCFG.cpp
index 9d0757a7146..3d1a5bea97c 100644
--- a/llvm/lib/Transforms/Scalar/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyCFG.cpp
@@ -26,7 +26,6 @@
 #include "llvm/Transforms/Utils/Local.h"
 #include "llvm/Constants.h"
 #include "llvm/Instructions.h"
-#include "llvm/Intrinsics.h"
 #include "llvm/Module.h"
 #include "llvm/ParameterAttributes.h"
 #include "llvm/Support/CFG.h"
@@ -155,20 +154,8 @@ static bool RemoveUnreachableBlocks(Function &F) {
   bool Changed = MarkAliveBlocks(F.begin(), Reachable);
   
   // If there are unreachable blocks in the CFG...
-  if (Reachable.size() == F.size()) {
-    if (F.size() == 1) {
-      // If the function has only one block with an "unreachable" instruction,
-      // then we should create *some* code for it. Issue a "trap" instead.
-      BasicBlock &BB = F.front();
-
-      if (BB.size() == 1 && dyn_cast<UnreachableInst>(&BB.front()))
-        new CallInst(Intrinsic::getDeclaration(F.getParent(),
-                                               Intrinsic::trap),
-                     "", &BB.front());
-    }
-
+  if (Reachable.size() == F.size())
     return Changed;
-  }
   
   assert(Reachable.size() < F.size());
   NumSimpl += F.size()-Reachable.size();