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diff --git a/llvm/lib/Transforms/Scalar/LowerInvoke.cpp b/llvm/lib/Transforms/Scalar/LowerInvoke.cpp
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-//===- LowerInvoke.cpp - Eliminate Invoke & Unwind instructions -----------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This transformation is designed for use by code generators which do not yet
-// support stack unwinding. This pass supports two models of exception handling
-// lowering, the 'cheap' support and the 'expensive' support.
-//
-// 'Cheap' exception handling support gives the program the ability to execute
-// any program which does not "throw an exception", by turning 'invoke'
-// instructions into calls and by turning 'unwind' instructions into calls to
-// abort(). If the program does dynamically use the unwind instruction, the
-// program will print a message then abort.
-//
-// 'Expensive' exception handling support gives the full exception handling
-// support to the program at the cost of making the 'invoke' instruction
-// really expensive. It basically inserts setjmp/longjmp calls to emulate the
-// exception handling as necessary.
-//
-// Because the 'expensive' support slows down programs a lot, and EH is only
-// used for a subset of the programs, it must be specifically enabled by an
-// option.
-//
-// Note that after this pass runs the CFG is not entirely accurate (exceptional
-// control flow edges are not correct anymore) so only very simple things should
-// be done after the lowerinvoke pass has run (like generation of native code).
-// This should not be used as a general purpose "my LLVM-to-LLVM pass doesn't
-// support the invoke instruction yet" lowering pass.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Instructions.h"
-#include "llvm/Module.h"
-#include "llvm/Pass.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/Visibility.h"
-#include <csetjmp>
-using namespace llvm;
-
-namespace {
- Statistic<> NumInvokes("lowerinvoke", "Number of invokes replaced");
- Statistic<> NumUnwinds("lowerinvoke", "Number of unwinds replaced");
- Statistic<> NumSpilled("lowerinvoke",
- "Number of registers live across unwind edges");
- cl::opt<bool> ExpensiveEHSupport("enable-correct-eh-support",
- cl::desc("Make the -lowerinvoke pass insert expensive, but correct, EH code"));
-
- class VISIBILITY_HIDDEN LowerInvoke : public FunctionPass {
- // Used for both models.
- Function *WriteFn;
- Function *AbortFn;
- Value *AbortMessage;
- unsigned AbortMessageLength;
-
- // Used for expensive EH support.
- const Type *JBLinkTy;
- GlobalVariable *JBListHead;
- Function *SetJmpFn, *LongJmpFn;
- public:
- LowerInvoke(unsigned Size = 200, unsigned Align = 0) : JumpBufSize(Size),
- JumpBufAlign(Align) {}
- bool doInitialization(Module &M);
- bool runOnFunction(Function &F);
-
- virtual void getAnalysisUsage(AnalysisUsage &AU) const {
- // This is a cluster of orthogonal Transforms
- AU.addPreservedID(PromoteMemoryToRegisterID);
- AU.addPreservedID(LowerSelectID);
- AU.addPreservedID(LowerSwitchID);
- AU.addPreservedID(LowerAllocationsID);
- }
-
- private:
- void createAbortMessage();
- void writeAbortMessage(Instruction *IB);
- bool insertCheapEHSupport(Function &F);
- void splitLiveRangesLiveAcrossInvokes(std::vector<InvokeInst*> &Invokes);
- void rewriteExpensiveInvoke(InvokeInst *II, unsigned InvokeNo,
- AllocaInst *InvokeNum, SwitchInst *CatchSwitch);
- bool insertExpensiveEHSupport(Function &F);
-
- unsigned JumpBufSize;
- unsigned JumpBufAlign;
- };
-
- RegisterOpt<LowerInvoke>
- X("lowerinvoke", "Lower invoke and unwind, for unwindless code generators");
-}
-
-const PassInfo *llvm::LowerInvokePassID = X.getPassInfo();
-
-// Public Interface To the LowerInvoke pass.
-FunctionPass *llvm::createLowerInvokePass(unsigned JumpBufSize,
- unsigned JumpBufAlign) {
- return new LowerInvoke(JumpBufSize, JumpBufAlign);
-}
-
-// doInitialization - Make sure that there is a prototype for abort in the
-// current module.
-bool LowerInvoke::doInitialization(Module &M) {
- const Type *VoidPtrTy = PointerType::get(Type::SByteTy);
- AbortMessage = 0;
- if (ExpensiveEHSupport) {
- // Insert a type for the linked list of jump buffers.
- const Type *JmpBufTy = ArrayType::get(VoidPtrTy, JumpBufSize);
-
- { // The type is recursive, so use a type holder.
- std::vector<const Type*> Elements;
- Elements.push_back(JmpBufTy);
- OpaqueType *OT = OpaqueType::get();
- Elements.push_back(PointerType::get(OT));
- PATypeHolder JBLType(StructType::get(Elements));
- OT->refineAbstractTypeTo(JBLType.get()); // Complete the cycle.
- JBLinkTy = JBLType.get();
- M.addTypeName("llvm.sjljeh.jmpbufty", JBLinkTy);
- }
-
- const Type *PtrJBList = PointerType::get(JBLinkTy);
-
- // Now that we've done that, insert the jmpbuf list head global, unless it
- // already exists.
- if (!(JBListHead = M.getGlobalVariable("llvm.sjljeh.jblist", PtrJBList)))
- JBListHead = new GlobalVariable(PtrJBList, false,
- GlobalValue::LinkOnceLinkage,
- Constant::getNullValue(PtrJBList),
- "llvm.sjljeh.jblist", &M);
- SetJmpFn = M.getOrInsertFunction("llvm.setjmp", Type::IntTy,
- PointerType::get(JmpBufTy), (Type *)0);
- LongJmpFn = M.getOrInsertFunction("llvm.longjmp", Type::VoidTy,
- PointerType::get(JmpBufTy),
- Type::IntTy, (Type *)0);
- }
-
- // We need the 'write' and 'abort' functions for both models.
- AbortFn = M.getOrInsertFunction("abort", Type::VoidTy, (Type *)0);
-
- // Unfortunately, 'write' can end up being prototyped in several different
- // ways. If the user defines a three (or more) operand function named 'write'
- // we will use their prototype. We _do not_ want to insert another instance
- // of a write prototype, because we don't know that the funcresolve pass will
- // run after us. If there is a definition of a write function, but it's not
- // suitable for our uses, we just don't emit write calls. If there is no
- // write prototype at all, we just add one.
- if (Function *WF = M.getNamedFunction("write")) {
- if (WF->getFunctionType()->getNumParams() > 3 ||
- WF->getFunctionType()->isVarArg())
- WriteFn = WF;
- else
- WriteFn = 0;
- } else {
- WriteFn = M.getOrInsertFunction("write", Type::VoidTy, Type::IntTy,
- VoidPtrTy, Type::IntTy, (Type *)0);
- }
- return true;
-}
-
-void LowerInvoke::createAbortMessage() {
- Module &M = *WriteFn->getParent();
- if (ExpensiveEHSupport) {
- // The abort message for expensive EH support tells the user that the
- // program 'unwound' without an 'invoke' instruction.
- Constant *Msg =
- ConstantArray::get("ERROR: Exception thrown, but not caught!\n");
- AbortMessageLength = Msg->getNumOperands()-1; // don't include \0
-
- GlobalVariable *MsgGV = new GlobalVariable(Msg->getType(), true,
- GlobalValue::InternalLinkage,
- Msg, "abortmsg", &M);
- std::vector<Constant*> GEPIdx(2, Constant::getNullValue(Type::IntTy));
- AbortMessage = ConstantExpr::getGetElementPtr(MsgGV, GEPIdx);
- } else {
- // The abort message for cheap EH support tells the user that EH is not
- // enabled.
- Constant *Msg =
- ConstantArray::get("Exception handler needed, but not enabled. Recompile"
- " program with -enable-correct-eh-support.\n");
- AbortMessageLength = Msg->getNumOperands()-1; // don't include \0
-
- GlobalVariable *MsgGV = new GlobalVariable(Msg->getType(), true,
- GlobalValue::InternalLinkage,
- Msg, "abortmsg", &M);
- std::vector<Constant*> GEPIdx(2, Constant::getNullValue(Type::IntTy));
- AbortMessage = ConstantExpr::getGetElementPtr(MsgGV, GEPIdx);
- }
-}
-
-
-void LowerInvoke::writeAbortMessage(Instruction *IB) {
- if (WriteFn) {
- if (AbortMessage == 0) createAbortMessage();
-
- // These are the arguments we WANT...
- std::vector<Value*> Args;
- Args.push_back(ConstantInt::get(Type::IntTy, 2));
- Args.push_back(AbortMessage);
- Args.push_back(ConstantInt::get(Type::IntTy, AbortMessageLength));
-
- // If the actual declaration of write disagrees, insert casts as
- // appropriate.
- const FunctionType *FT = WriteFn->getFunctionType();
- unsigned NumArgs = FT->getNumParams();
- for (unsigned i = 0; i != 3; ++i)
- if (i < NumArgs && FT->getParamType(i) != Args[i]->getType())
- Args[i] = ConstantExpr::getCast(cast<Constant>(Args[i]),
- FT->getParamType(i));
-
- (new CallInst(WriteFn, Args, "", IB))->setTailCall();
- }
-}
-
-bool LowerInvoke::insertCheapEHSupport(Function &F) {
- bool Changed = false;
- for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
- if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator())) {
- // Insert a normal call instruction...
- std::string Name = II->getName(); II->setName("");
- CallInst *NewCall = new CallInst(II->getCalledValue(),
- std::vector<Value*>(II->op_begin()+3,
- II->op_end()), Name, II);
- NewCall->setCallingConv(II->getCallingConv());
- II->replaceAllUsesWith(NewCall);
-
- // Insert an unconditional branch to the normal destination.
- new BranchInst(II->getNormalDest(), II);
-
- // Remove any PHI node entries from the exception destination.
- II->getUnwindDest()->removePredecessor(BB);
-
- // Remove the invoke instruction now.
- BB->getInstList().erase(II);
-
- ++NumInvokes; Changed = true;
- } else if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
- // Insert a new call to write(2, AbortMessage, AbortMessageLength);
- writeAbortMessage(UI);
-
- // Insert a call to abort()
- (new CallInst(AbortFn, std::vector<Value*>(), "", UI))->setTailCall();
-
- // Insert a return instruction. This really should be a "barrier", as it
- // is unreachable.
- new ReturnInst(F.getReturnType() == Type::VoidTy ? 0 :
- Constant::getNullValue(F.getReturnType()), UI);
-
- // Remove the unwind instruction now.
- BB->getInstList().erase(UI);
-
- ++NumUnwinds; Changed = true;
- }
- return Changed;
-}
-
-/// rewriteExpensiveInvoke - Insert code and hack the function to replace the
-/// specified invoke instruction with a call.
-void LowerInvoke::rewriteExpensiveInvoke(InvokeInst *II, unsigned InvokeNo,
- AllocaInst *InvokeNum,
- SwitchInst *CatchSwitch) {
- ConstantUInt *InvokeNoC = ConstantUInt::get(Type::UIntTy, InvokeNo);
-
- // Insert a store of the invoke num before the invoke and store zero into the
- // location afterward.
- new StoreInst(InvokeNoC, InvokeNum, true, II); // volatile
-
- BasicBlock::iterator NI = II->getNormalDest()->begin();
- while (isa<PHINode>(NI)) ++NI;
- // nonvolatile.
- new StoreInst(Constant::getNullValue(Type::UIntTy), InvokeNum, false, NI);
-
- // Add a switch case to our unwind block.
- CatchSwitch->addCase(InvokeNoC, II->getUnwindDest());
-
- // Insert a normal call instruction.
- std::string Name = II->getName(); II->setName("");
- CallInst *NewCall = new CallInst(II->getCalledValue(),
- std::vector<Value*>(II->op_begin()+3,
- II->op_end()), Name,
- II);
- NewCall->setCallingConv(II->getCallingConv());
- II->replaceAllUsesWith(NewCall);
-
- // Replace the invoke with an uncond branch.
- new BranchInst(II->getNormalDest(), NewCall->getParent());
- II->eraseFromParent();
-}
-
-/// MarkBlocksLiveIn - Insert BB and all of its predescessors into LiveBBs until
-/// we reach blocks we've already seen.
-static void MarkBlocksLiveIn(BasicBlock *BB, std::set<BasicBlock*> &LiveBBs) {
- if (!LiveBBs.insert(BB).second) return; // already been here.
-
- for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI)
- MarkBlocksLiveIn(*PI, LiveBBs);
-}
-
-// First thing we need to do is scan the whole function for values that are
-// live across unwind edges. Each value that is live across an unwind edge
-// we spill into a stack location, guaranteeing that there is nothing live
-// across the unwind edge. This process also splits all critical edges
-// coming out of invoke's.
-void LowerInvoke::
-splitLiveRangesLiveAcrossInvokes(std::vector<InvokeInst*> &Invokes) {
- // First step, split all critical edges from invoke instructions.
- for (unsigned i = 0, e = Invokes.size(); i != e; ++i) {
- InvokeInst *II = Invokes[i];
- SplitCriticalEdge(II, 0, this);
- SplitCriticalEdge(II, 1, this);
- assert(!isa<PHINode>(II->getNormalDest()) &&
- !isa<PHINode>(II->getUnwindDest()) &&
- "critical edge splitting left single entry phi nodes?");
- }
-
- Function *F = Invokes.back()->getParent()->getParent();
-
- // To avoid having to handle incoming arguments specially, we lower each arg
- // to a copy instruction in the entry block. This ensure that the argument
- // value itself cannot be live across the entry block.
- BasicBlock::iterator AfterAllocaInsertPt = F->begin()->begin();
- while (isa<AllocaInst>(AfterAllocaInsertPt) &&
- isa<ConstantInt>(cast<AllocaInst>(AfterAllocaInsertPt)->getArraySize()))
- ++AfterAllocaInsertPt;
- for (Function::arg_iterator AI = F->arg_begin(), E = F->arg_end();
- AI != E; ++AI) {
- CastInst *NC = new CastInst(AI, AI->getType(), AI->getName()+".tmp",
- AfterAllocaInsertPt);
- AI->replaceAllUsesWith(NC);
- NC->setOperand(0, AI);
- }
-
- // Finally, scan the code looking for instructions with bad live ranges.
- for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
- for (BasicBlock::iterator II = BB->begin(), E = BB->end(); II != E; ++II) {
- // Ignore obvious cases we don't have to handle. In particular, most
- // instructions either have no uses or only have a single use inside the
- // current block. Ignore them quickly.
- Instruction *Inst = II;
- if (Inst->use_empty()) continue;
- if (Inst->hasOneUse() &&
- cast<Instruction>(Inst->use_back())->getParent() == BB &&
- !isa<PHINode>(Inst->use_back())) continue;
-
- // If this is an alloca in the entry block, it's not a real register
- // value.
- if (AllocaInst *AI = dyn_cast<AllocaInst>(Inst))
- if (isa<ConstantInt>(AI->getArraySize()) && BB == F->begin())
- continue;
-
- // Avoid iterator invalidation by copying users to a temporary vector.
- std::vector<Instruction*> Users;
- for (Value::use_iterator UI = Inst->use_begin(), E = Inst->use_end();
- UI != E; ++UI) {
- Instruction *User = cast<Instruction>(*UI);
- if (User->getParent() != BB || isa<PHINode>(User))
- Users.push_back(User);
- }
-
- // Scan all of the uses and see if the live range is live across an unwind
- // edge. If we find a use live across an invoke edge, create an alloca
- // and spill the value.
- AllocaInst *SpillLoc = 0;
- std::set<InvokeInst*> InvokesWithStoreInserted;
-
- // Find all of the blocks that this value is live in.
- std::set<BasicBlock*> LiveBBs;
- LiveBBs.insert(Inst->getParent());
- while (!Users.empty()) {
- Instruction *U = Users.back();
- Users.pop_back();
-
- if (!isa<PHINode>(U)) {
- MarkBlocksLiveIn(U->getParent(), LiveBBs);
- } else {
- // Uses for a PHI node occur in their predecessor block.
- PHINode *PN = cast<PHINode>(U);
- for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
- if (PN->getIncomingValue(i) == Inst)
- MarkBlocksLiveIn(PN->getIncomingBlock(i), LiveBBs);
- }
- }
-
- // Now that we know all of the blocks that this thing is live in, see if
- // it includes any of the unwind locations.
- bool NeedsSpill = false;
- for (unsigned i = 0, e = Invokes.size(); i != e; ++i) {
- BasicBlock *UnwindBlock = Invokes[i]->getUnwindDest();
- if (UnwindBlock != BB && LiveBBs.count(UnwindBlock)) {
- NeedsSpill = true;
- }
- }
-
- // If we decided we need a spill, do it.
- if (NeedsSpill) {
- ++NumSpilled;
- DemoteRegToStack(*Inst, true);
- }
- }
-}
-
-bool LowerInvoke::insertExpensiveEHSupport(Function &F) {
- std::vector<ReturnInst*> Returns;
- std::vector<UnwindInst*> Unwinds;
- std::vector<InvokeInst*> Invokes;
-
- for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
- if (ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator())) {
- // Remember all return instructions in case we insert an invoke into this
- // function.
- Returns.push_back(RI);
- } else if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator())) {
- Invokes.push_back(II);
- } else if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) {
- Unwinds.push_back(UI);
- }
-
- if (Unwinds.empty() && Invokes.empty()) return false;
-
- NumInvokes += Invokes.size();
- NumUnwinds += Unwinds.size();
-
- // TODO: This is not an optimal way to do this. In particular, this always
- // inserts setjmp calls into the entries of functions with invoke instructions
- // even though there are possibly paths through the function that do not
- // execute any invokes. In particular, for functions with early exits, e.g.
- // the 'addMove' method in hexxagon, it would be nice to not have to do the
- // setjmp stuff on the early exit path. This requires a bit of dataflow, but
- // would not be too hard to do.
-
- // If we have an invoke instruction, insert a setjmp that dominates all
- // invokes. After the setjmp, use a cond branch that goes to the original
- // code path on zero, and to a designated 'catch' block of nonzero.
- Value *OldJmpBufPtr = 0;
- if (!Invokes.empty()) {
- // First thing we need to do is scan the whole function for values that are
- // live across unwind edges. Each value that is live across an unwind edge
- // we spill into a stack location, guaranteeing that there is nothing live
- // across the unwind edge. This process also splits all critical edges
- // coming out of invoke's.
- splitLiveRangesLiveAcrossInvokes(Invokes);
-
- BasicBlock *EntryBB = F.begin();
-
- // Create an alloca for the incoming jump buffer ptr and the new jump buffer
- // that needs to be restored on all exits from the function. This is an
- // alloca because the value needs to be live across invokes.
- AllocaInst *JmpBuf =
- new AllocaInst(JBLinkTy, 0, JumpBufAlign, "jblink", F.begin()->begin());
-
- std::vector<Value*> Idx;
- Idx.push_back(Constant::getNullValue(Type::IntTy));
- Idx.push_back(ConstantUInt::get(Type::UIntTy, 1));
- OldJmpBufPtr = new GetElementPtrInst(JmpBuf, Idx, "OldBuf",
- EntryBB->getTerminator());
-
- // Copy the JBListHead to the alloca.
- Value *OldBuf = new LoadInst(JBListHead, "oldjmpbufptr", true,
- EntryBB->getTerminator());
- new StoreInst(OldBuf, OldJmpBufPtr, true, EntryBB->getTerminator());
-
- // Add the new jumpbuf to the list.
- new StoreInst(JmpBuf, JBListHead, true, EntryBB->getTerminator());
-
- // Create the catch block. The catch block is basically a big switch
- // statement that goes to all of the invoke catch blocks.
- BasicBlock *CatchBB = new BasicBlock("setjmp.catch", &F);
-
- // Create an alloca which keeps track of which invoke is currently
- // executing. For normal calls it contains zero.
- AllocaInst *InvokeNum = new AllocaInst(Type::UIntTy, 0, "invokenum",
- EntryBB->begin());
- new StoreInst(ConstantInt::get(Type::UIntTy, 0), InvokeNum, true,
- EntryBB->getTerminator());
-
- // Insert a load in the Catch block, and a switch on its value. By default,
- // we go to a block that just does an unwind (which is the correct action
- // for a standard call).
- BasicBlock *UnwindBB = new BasicBlock("unwindbb", &F);
- Unwinds.push_back(new UnwindInst(UnwindBB));
-
- Value *CatchLoad = new LoadInst(InvokeNum, "invoke.num", true, CatchBB);
- SwitchInst *CatchSwitch =
- new SwitchInst(CatchLoad, UnwindBB, Invokes.size(), CatchBB);
-
- // Now that things are set up, insert the setjmp call itself.
-
- // Split the entry block to insert the conditional branch for the setjmp.
- BasicBlock *ContBlock = EntryBB->splitBasicBlock(EntryBB->getTerminator(),
- "setjmp.cont");
-
- Idx[1] = ConstantUInt::get(Type::UIntTy, 0);
- Value *JmpBufPtr = new GetElementPtrInst(JmpBuf, Idx, "TheJmpBuf",
- EntryBB->getTerminator());
- Value *SJRet = new CallInst(SetJmpFn, JmpBufPtr, "sjret",
- EntryBB->getTerminator());
-
- // Compare the return value to zero.
- Value *IsNormal = BinaryOperator::createSetEQ(SJRet,
- Constant::getNullValue(SJRet->getType()),
- "notunwind", EntryBB->getTerminator());
- // Nuke the uncond branch.
- EntryBB->getTerminator()->eraseFromParent();
-
- // Put in a new condbranch in its place.
- new BranchInst(ContBlock, CatchBB, IsNormal, EntryBB);
-
- // At this point, we are all set up, rewrite each invoke instruction.
- for (unsigned i = 0, e = Invokes.size(); i != e; ++i)
- rewriteExpensiveInvoke(Invokes[i], i+1, InvokeNum, CatchSwitch);
- }
-
- // We know that there is at least one unwind.
-
- // Create three new blocks, the block to load the jmpbuf ptr and compare
- // against null, the block to do the longjmp, and the error block for if it
- // is null. Add them at the end of the function because they are not hot.
- BasicBlock *UnwindHandler = new BasicBlock("dounwind", &F);
- BasicBlock *UnwindBlock = new BasicBlock("unwind", &F);
- BasicBlock *TermBlock = new BasicBlock("unwinderror", &F);
-
- // If this function contains an invoke, restore the old jumpbuf ptr.
- Value *BufPtr;
- if (OldJmpBufPtr) {
- // Before the return, insert a copy from the saved value to the new value.
- BufPtr = new LoadInst(OldJmpBufPtr, "oldjmpbufptr", UnwindHandler);
- new StoreInst(BufPtr, JBListHead, UnwindHandler);
- } else {
- BufPtr = new LoadInst(JBListHead, "ehlist", UnwindHandler);
- }
-
- // Load the JBList, if it's null, then there was no catch!
- Value *NotNull = BinaryOperator::createSetNE(BufPtr,
- Constant::getNullValue(BufPtr->getType()),
- "notnull", UnwindHandler);
- new BranchInst(UnwindBlock, TermBlock, NotNull, UnwindHandler);
-
- // Create the block to do the longjmp.
- // Get a pointer to the jmpbuf and longjmp.
- std::vector<Value*> Idx;
- Idx.push_back(Constant::getNullValue(Type::IntTy));
- Idx.push_back(ConstantUInt::get(Type::UIntTy, 0));
- Idx[0] = new GetElementPtrInst(BufPtr, Idx, "JmpBuf", UnwindBlock);
- Idx[1] = ConstantInt::get(Type::IntTy, 1);
- new CallInst(LongJmpFn, Idx, "", UnwindBlock);
- new UnreachableInst(UnwindBlock);
-
- // Set up the term block ("throw without a catch").
- new UnreachableInst(TermBlock);
-
- // Insert a new call to write(2, AbortMessage, AbortMessageLength);
- writeAbortMessage(TermBlock->getTerminator());
-
- // Insert a call to abort()
- (new CallInst(AbortFn, std::vector<Value*>(), "",
- TermBlock->getTerminator()))->setTailCall();
-
-
- // Replace all unwinds with a branch to the unwind handler.
- for (unsigned i = 0, e = Unwinds.size(); i != e; ++i) {
- new BranchInst(UnwindHandler, Unwinds[i]);
- Unwinds[i]->eraseFromParent();
- }
-
- // Finally, for any returns from this function, if this function contains an
- // invoke, restore the old jmpbuf pointer to its input value.
- if (OldJmpBufPtr) {
- for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
- ReturnInst *R = Returns[i];
-
- // Before the return, insert a copy from the saved value to the new value.
- Value *OldBuf = new LoadInst(OldJmpBufPtr, "oldjmpbufptr", true, R);
- new StoreInst(OldBuf, JBListHead, true, R);
- }
- }
-
- return true;
-}
-
-bool LowerInvoke::runOnFunction(Function &F) {
- if (ExpensiveEHSupport)
- return insertExpensiveEHSupport(F);
- else
- return insertCheapEHSupport(F);
-}
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