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diff --git a/contrib/llvm/lib/Transforms/IPO/PruneEH.cpp b/contrib/llvm/lib/Transforms/IPO/PruneEH.cpp
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+++ b/contrib/llvm/lib/Transforms/IPO/PruneEH.cpp
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+//===- PruneEH.cpp - Pass which deletes unused exception handlers ---------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements a simple interprocedural pass which walks the
+// call-graph, turning invoke instructions into calls, iff the callee cannot
+// throw an exception, and marking functions 'nounwind' if they cannot throw.
+// It implements this as a bottom-up traversal of the call-graph.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "prune-eh"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/CallGraphSCCPass.h"
+#include "llvm/Constants.h"
+#include "llvm/Function.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/Analysis/CallGraph.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/CFG.h"
+#include <set>
+#include <algorithm>
+using namespace llvm;
+
+STATISTIC(NumRemoved, "Number of invokes removed");
+STATISTIC(NumUnreach, "Number of noreturn calls optimized");
+
+namespace {
+  struct PruneEH : public CallGraphSCCPass {
+    static char ID; // Pass identification, replacement for typeid
+    PruneEH() : CallGraphSCCPass(&ID) {}
+
+    // runOnSCC - Analyze the SCC, performing the transformation if possible.
+    bool runOnSCC(CallGraphSCC &SCC);
+
+    bool SimplifyFunction(Function *F);
+    void DeleteBasicBlock(BasicBlock *BB);
+  };
+}
+
+char PruneEH::ID = 0;
+static RegisterPass<PruneEH>
+X("prune-eh", "Remove unused exception handling info");
+
+Pass *llvm::createPruneEHPass() { return new PruneEH(); }
+
+
+bool PruneEH::runOnSCC(CallGraphSCC &SCC) {
+  SmallPtrSet<CallGraphNode *, 8> SCCNodes;
+  CallGraph &CG = getAnalysis<CallGraph>();
+  bool MadeChange = false;
+
+  // Fill SCCNodes with the elements of the SCC.  Used for quickly
+  // looking up whether a given CallGraphNode is in this SCC.
+  for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I)
+    SCCNodes.insert(*I);
+
+  // First pass, scan all of the functions in the SCC, simplifying them
+  // according to what we know.
+  for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I)
+    if (Function *F = (*I)->getFunction())
+      MadeChange |= SimplifyFunction(F);
+
+  // Next, check to see if any callees might throw or if there are any external
+  // functions in this SCC: if so, we cannot prune any functions in this SCC.
+  // Definitions that are weak and not declared non-throwing might be 
+  // overridden at linktime with something that throws, so assume that.
+  // If this SCC includes the unwind instruction, we KNOW it throws, so
+  // obviously the SCC might throw.
+  //
+  bool SCCMightUnwind = false, SCCMightReturn = false;
+  for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); 
+       (!SCCMightUnwind || !SCCMightReturn) && I != E; ++I) {
+    Function *F = (*I)->getFunction();
+    if (F == 0) {
+      SCCMightUnwind = true;
+      SCCMightReturn = true;
+    } else if (F->isDeclaration() || F->mayBeOverridden()) {
+      SCCMightUnwind |= !F->doesNotThrow();
+      SCCMightReturn |= !F->doesNotReturn();
+    } else {
+      bool CheckUnwind = !SCCMightUnwind && !F->doesNotThrow();
+      bool CheckReturn = !SCCMightReturn && !F->doesNotReturn();
+
+      if (!CheckUnwind && !CheckReturn)
+        continue;
+
+      // Check to see if this function performs an unwind or calls an
+      // unwinding function.
+      for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
+        if (CheckUnwind && isa<UnwindInst>(BB->getTerminator())) {
+          // Uses unwind!
+          SCCMightUnwind = true;
+        } else if (CheckReturn && isa<ReturnInst>(BB->getTerminator())) {
+          SCCMightReturn = true;
+        }
+
+        // Invoke instructions don't allow unwinding to continue, so we are
+        // only interested in call instructions.
+        if (CheckUnwind && !SCCMightUnwind)
+          for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
+            if (CallInst *CI = dyn_cast<CallInst>(I)) {
+              if (CI->doesNotThrow()) {
+                // This call cannot throw.
+              } else if (Function *Callee = CI->getCalledFunction()) {
+                CallGraphNode *CalleeNode = CG[Callee];
+                // If the callee is outside our current SCC then we may
+                // throw because it might.
+                if (!SCCNodes.count(CalleeNode)) {
+                  SCCMightUnwind = true;
+                  break;
+                }
+              } else {
+                // Indirect call, it might throw.
+                SCCMightUnwind = true;
+                break;
+              }
+            }
+        if (SCCMightUnwind && SCCMightReturn) break;
+      }
+    }
+  }
+
+  // If the SCC doesn't unwind or doesn't throw, note this fact.
+  if (!SCCMightUnwind || !SCCMightReturn)
+    for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) {
+      Attributes NewAttributes = Attribute::None;
+
+      if (!SCCMightUnwind)
+        NewAttributes |= Attribute::NoUnwind;
+      if (!SCCMightReturn)
+        NewAttributes |= Attribute::NoReturn;
+
+      Function *F = (*I)->getFunction();
+      const AttrListPtr &PAL = F->getAttributes();
+      const AttrListPtr &NPAL = PAL.addAttr(~0, NewAttributes);
+      if (PAL != NPAL) {
+        MadeChange = true;
+        F->setAttributes(NPAL);
+      }
+    }
+
+  for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) {
+    // Convert any invoke instructions to non-throwing functions in this node
+    // into call instructions with a branch.  This makes the exception blocks
+    // dead.
+    if (Function *F = (*I)->getFunction())
+      MadeChange |= SimplifyFunction(F);
+  }
+
+  return MadeChange;
+}
+
+
+// SimplifyFunction - Given information about callees, simplify the specified
+// function if we have invokes to non-unwinding functions or code after calls to
+// no-return functions.
+bool PruneEH::SimplifyFunction(Function *F) {
+  bool MadeChange = false;
+  for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
+    if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator()))
+      if (II->doesNotThrow()) {
+        SmallVector<Value*, 8> Args(II->op_begin(), II->op_end() - 3);
+        // Insert a call instruction before the invoke.
+        CallInst *Call = CallInst::Create(II->getCalledValue(),
+                                          Args.begin(), Args.end(), "", II);
+        Call->takeName(II);
+        Call->setCallingConv(II->getCallingConv());
+        Call->setAttributes(II->getAttributes());
+
+        // Anything that used the value produced by the invoke instruction
+        // now uses the value produced by the call instruction.  Note that we
+        // do this even for void functions and calls with no uses so that the
+        // callgraph edge is updated.
+        II->replaceAllUsesWith(Call);
+        BasicBlock *UnwindBlock = II->getUnwindDest();
+        UnwindBlock->removePredecessor(II->getParent());
+
+        // Insert a branch to the normal destination right before the
+        // invoke.
+        BranchInst::Create(II->getNormalDest(), II);
+
+        // Finally, delete the invoke instruction!
+        BB->getInstList().pop_back();
+
+        // If the unwind block is now dead, nuke it.
+        if (pred_begin(UnwindBlock) == pred_end(UnwindBlock))
+          DeleteBasicBlock(UnwindBlock);  // Delete the new BB.
+
+        ++NumRemoved;
+        MadeChange = true;
+      }
+
+    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; )
+      if (CallInst *CI = dyn_cast<CallInst>(I++))
+        if (CI->doesNotReturn() && !isa<UnreachableInst>(I)) {
+          // This call calls a function that cannot return.  Insert an
+          // unreachable instruction after it and simplify the code.  Do this
+          // by splitting the BB, adding the unreachable, then deleting the
+          // new BB.
+          BasicBlock *New = BB->splitBasicBlock(I);
+
+          // Remove the uncond branch and add an unreachable.
+          BB->getInstList().pop_back();
+          new UnreachableInst(BB->getContext(), BB);
+
+          DeleteBasicBlock(New);  // Delete the new BB.
+          MadeChange = true;
+          ++NumUnreach;
+          break;
+        }
+  }
+
+  return MadeChange;
+}
+
+/// DeleteBasicBlock - remove the specified basic block from the program,
+/// updating the callgraph to reflect any now-obsolete edges due to calls that
+/// exist in the BB.
+void PruneEH::DeleteBasicBlock(BasicBlock *BB) {
+  assert(pred_begin(BB) == pred_end(BB) && "BB is not dead!");
+  CallGraph &CG = getAnalysis<CallGraph>();
+
+  CallGraphNode *CGN = CG[BB->getParent()];
+  for (BasicBlock::iterator I = BB->end(), E = BB->begin(); I != E; ) {
+    --I;
+    if (CallInst *CI = dyn_cast<CallInst>(I)) {
+      if (!isa<DbgInfoIntrinsic>(I))
+        CGN->removeCallEdgeFor(CI);
+    } else if (InvokeInst *II = dyn_cast<InvokeInst>(I))
+      CGN->removeCallEdgeFor(II);
+    if (!I->use_empty())
+      I->replaceAllUsesWith(UndefValue::get(I->getType()));
+  }
+
+  // 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);
+
+  BB->eraseFromParent();
+}