From b976e668165e1875a8f1eb7af800e33bb1e4393d Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Sat, 16 Oct 2004 18:08:06 +0000
Subject: [PATCH] Add support for undef and unreachable

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17041 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Linker/LinkModules.cpp  | 2 +-
 lib/VMCore/AsmWriter.cpp    | 3 +++
 lib/VMCore/Instruction.cpp  | 1 +
 lib/VMCore/Instructions.cpp | 9 +++++++++
 lib/VMCore/Linker.cpp       | 2 +-
 5 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp
index 70bd22cd444..fbf09781bae 100644
--- a/lib/Linker/LinkModules.cpp
+++ b/lib/Linker/LinkModules.cpp
@@ -310,7 +310,7 @@ static Value *RemapOperand(const Value *In,
         Operands[i] =
           cast<Constant>(RemapOperand(CPS->getOperand(i), LocalMap, GlobalMap));
       Result = ConstantStruct::get(cast<StructType>(CPS->getType()), Operands);
-    } else if (isa<ConstantPointerNull>(CPV)) {
+    } else if (isa<ConstantPointerNull>(CPV) || isa<UndefValue>(CPV)) {
       Result = const_cast<Constant*>(CPV);
     } else if (isa<GlobalValue>(CPV)) {
       Result = cast<Constant>(RemapOperand(CPV, LocalMap, GlobalMap));
diff --git a/lib/VMCore/AsmWriter.cpp b/lib/VMCore/AsmWriter.cpp
index 236e243caad..2e973feb161 100644
--- a/lib/VMCore/AsmWriter.cpp
+++ b/lib/VMCore/AsmWriter.cpp
@@ -518,6 +518,9 @@ static void WriteConstantInt(std::ostream &Out, const Constant *CV,
   } else if (isa<ConstantPointerNull>(CV)) {
     Out << "null";
 
+  } else if (isa<UndefValue>(CV)) {
+    Out << "undef";
+
   } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
     Out << CE->getOpcodeName() << " (";
     
diff --git a/lib/VMCore/Instruction.cpp b/lib/VMCore/Instruction.cpp
index 4ea5775330a..17970ac9ba9 100644
--- a/lib/VMCore/Instruction.cpp
+++ b/lib/VMCore/Instruction.cpp
@@ -88,6 +88,7 @@ const char *Instruction::getOpcodeName(unsigned OpCode) {
   case Switch: return "switch";
   case Invoke: return "invoke";
   case Unwind: return "unwind";
+  case Unreachable: return "unreachable";
     
   // Standard binary operators...
   case Add: return "add";
diff --git a/lib/VMCore/Instructions.cpp b/lib/VMCore/Instructions.cpp
index 38e9255a9b3..029ee6a0f6b 100644
--- a/lib/VMCore/Instructions.cpp
+++ b/lib/VMCore/Instructions.cpp
@@ -248,6 +248,14 @@ void UnwindInst::setSuccessor(unsigned idx, BasicBlock *NewSucc) {
   assert(0 && "UnwindInst has no successors!");
 }
 
+//===----------------------------------------------------------------------===//
+//                      UnreachableInst Implementation
+//===----------------------------------------------------------------------===//
+
+void UnreachableInst::setSuccessor(unsigned idx, BasicBlock *NewSucc) {
+  assert(0 && "UnreachableInst has no successors!");
+}
+
 //===----------------------------------------------------------------------===//
 //                        BranchInst Implementation
 //===----------------------------------------------------------------------===//
@@ -832,3 +840,4 @@ BranchInst *BranchInst::clone() const { return new BranchInst(*this); }
 SwitchInst *SwitchInst::clone() const { return new SwitchInst(*this); }
 InvokeInst *InvokeInst::clone() const { return new InvokeInst(*this); }
 UnwindInst *UnwindInst::clone() const { return new UnwindInst(); }
+UnreachableInst *UnreachableInst::clone() const { return new UnreachableInst();}
diff --git a/lib/VMCore/Linker.cpp b/lib/VMCore/Linker.cpp
index 70bd22cd444..fbf09781bae 100644
--- a/lib/VMCore/Linker.cpp
+++ b/lib/VMCore/Linker.cpp
@@ -310,7 +310,7 @@ static Value *RemapOperand(const Value *In,
         Operands[i] =
           cast<Constant>(RemapOperand(CPS->getOperand(i), LocalMap, GlobalMap));
       Result = ConstantStruct::get(cast<StructType>(CPS->getType()), Operands);
-    } else if (isa<ConstantPointerNull>(CPV)) {
+    } else if (isa<ConstantPointerNull>(CPV) || isa<UndefValue>(CPV)) {
       Result = const_cast<Constant*>(CPV);
     } else if (isa<GlobalValue>(CPV)) {
       Result = cast<Constant>(RemapOperand(CPV, LocalMap, GlobalMap));
-- 
2.34.1