remove dead omp code

Author: AlexMaclean

llvm/lib/Transforms/IPO/OpenMPOpt.cpp

@@ -5906,39 +5906,19 @@ bool llvm::omp::isOpenMPKernel(Function &Fn) {
 }
 
 KernelSet llvm::omp::getDeviceKernels(Module &M) {
-  // TODO: Create a more cross-platform way of determining device kernels.
   KernelSet Kernels;
 
-  DenseSet<const Function *> SeenKernels;
-  auto ProcessKernel = [&](Function &KF) {
-    if (SeenKernels.insert(&KF).second) {
+  for (Function &F : M)
+    if (F.hasKernelCallingConv()) {
       // We are only interested in OpenMP target regions. Others, such as
       // kernels generated by CUDA but linked together, are not interesting to
       // this pass.
-      if (isOpenMPKernel(KF)) {
+      if (isOpenMPKernel(F)) {
         ++NumOpenMPTargetRegionKernels;
-        Kernels.insert(&KF);
+        Kernels.insert(&F);
       } else
         ++NumNonOpenMPTargetRegionKernels;
     }
-  };
-
-  if (NamedMDNode *MD = M.getNamedMetadata("nvvm.annotations"))
-    for (auto *Op : MD->operands()) {
-      if (Op->getNumOperands() < 2)
-        continue;
-      MDString *KindID = dyn_cast<MDString>(Op->getOperand(1));
-      if (!KindID || KindID->getString() != "kernel")
-        continue;
-
-      if (auto *KernelFn =
-              mdconst::dyn_extract_or_null<Function>(Op->getOperand(0)))
-        ProcessKernel(*KernelFn);
-    }
-
-  for (Function &F : M)
-    if (F.hasKernelCallingConv())
-      ProcessKernel(F);
 
   return Kernels;
 }