commit 7204cff0a121ebc770cf81f7f94679ae7324daae
author David Majnemer <david.majnemer@gmail.com> Fri Nov 06 21:26:32 2015 +0000
committer David Majnemer <david.majnemer@gmail.com> Fri Nov 06 21:26:32 2015 +0000
tree 05c31a6bb4c2795d9bccd8a17da44149082152c2
parent d9f87b46420998bc932bacce5f9e29b98b61fb55

[InstCombine] Don't RAUW tokens with undef

Let SimplifyCFG remove unreachable BBs which define token instructions.

llvm-svn: 252343

llvm/lib/Transforms/InstCombine/InstructionCombining.cpp

diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index ac535f9..f024ab1 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -3012,7 +3012,7 @@
     while (EndInst != BB->begin()) {
       // Delete the next to last instruction.
       Instruction *Inst = &*--EndInst->getIterator();
-      if (!Inst->use_empty())
+      if (!Inst->use_empty() && !Inst->getType()->isTokenTy())
         Inst->replaceAllUsesWith(UndefValue::get(Inst->getType()));
       if (Inst->isEHPad()) {
         EndInst = Inst;
@@ -3022,7 +3022,8 @@
         ++NumDeadInst;
         MadeIRChange = true;
       }
-      Inst->eraseFromParent();
+      if (!Inst->getType()->isTokenTy())
+        Inst->eraseFromParent();
     }
   }