[PruneEH] FuncletPads must not have undef operands

Instead of RAUW with undef, replace the first non-token instruction with
unreachable.

This fixes PR26263.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@258611 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/IPO/PruneEH.cpp b/lib/Transforms/IPO/PruneEH.cpp
index da3bf23..c2f55d8 100644 (file)
--- a/lib/Transforms/IPO/PruneEH.cpp
+++ b/lib/Transforms/IPO/PruneEH.cpp
@@ -228,10 +228,17 @@ void PruneEH::DeleteBasicBlock(BasicBlock *BB) {
   assert(pred_empty(BB) && "BB is not dead!");
   CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph();
 
+  Instruction *TokenInst = nullptr;
+
   CallGraphNode *CGN = CG[BB->getParent()];
   for (BasicBlock::iterator I = BB->end(), E = BB->begin(); I != E; ) {
     --I;
 
+    if (I->getType()->isTokenTy()) {
+      TokenInst = &*I;
+      break;
+    }
+
     if (auto CS = CallSite (&*I)) {
       const Function *Callee = CS.getCalledFunction();
       if (!Callee || !Intrinsic::isLeaf(Callee->getIntrinsicID()))
@@ -244,11 +251,15 @@ void PruneEH::DeleteBasicBlock(BasicBlock *BB) {
       I->replaceAllUsesWith(UndefValue::get(I->getType()));
   }
 
-  // Get the list of successors of this block.
-  std::vector<BasicBlock*> Succs(succ_begin(BB), succ_end(BB));
+  if (TokenInst) {
+    changeToUnreachable(TokenInst->getNextNode(), /*UseLLVMTrap=*/false);
+  } else {
+    // Get the list of successors of this block.
+    std::vector<BasicBlock *> Succs(succ_begin(BB), succ_end(BB));
 
-  for (unsigned i = 0, e = Succs.size(); i != e; ++i)
-    Succs[i]->removePredecessor(BB);
+    for (unsigned i = 0, e = Succs.size(); i != e; ++i)
+      Succs[i]->removePredecessor(BB);
 
-  BB->eraseFromParent();
+    BB->eraseFromParent();
+  }
 }

diff --git a/test/Transforms/PruneEH/pr26263.ll b/test/Transforms/PruneEH/pr26263.ll
new file mode 100644 (file)
index 0000000..3670f00
--- /dev/null
+++ b/test/Transforms/PruneEH/pr26263.ll
@@ -0,0 +1,30 @@
+; RUN: opt -prune-eh -S < %s | FileCheck %s
+target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
+target triple = "i386-pc-windows-msvc"
+
+declare void @neverthrows() nounwind
+
+define void @test1() personality i32 (...)* @__CxxFrameHandler3 {
+  invoke void @neverthrows()
+          to label %try.cont unwind label %cleanuppad
+
+try.cont:
+  ret void
+
+cleanuppad:
+  %cp = cleanuppad within none []
+  br label %cleanupret
+
+cleanupret:
+  cleanupret from %cp unwind to caller
+}
+
+; CHECK-LABEL: define void @test1(
+; CHECK: call void @neverthrows()
+
+; CHECK: %[[cp:.*]] = cleanuppad within none []
+; CHECK-NEXT: unreachable
+
+; CHECK: cleanupret from %[[cp]] unwind to caller
+
+declare i32 @__CxxFrameHandler3(...)