mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-18 12:29:21 +00:00
Initial checkin of the Setjmp/Longjmp lowering/transformation pass,
contributed by the masterful Bill Wendling! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8520 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
parent
c9d3e5721b
commit
6420f1cd50
501
lib/Transforms/IPO/LowerSetJmp.cpp
Normal file
501
lib/Transforms/IPO/LowerSetJmp.cpp
Normal file
@ -0,0 +1,501 @@
|
||||
//===- LowerSetJmp.cpp - Code pertaining to lowering set/long jumps -------===//
|
||||
//
|
||||
// This file implements the lowering of setjmp and longjmp to use the
|
||||
// LLVM invoke instruction as necessary.
|
||||
//
|
||||
// Lowering of longjmp is fairly trivial. We replace the call with a
|
||||
// call to the LLVM library function "__llvm_sjljeh_throw_longjmp()".
|
||||
// This unwinds the stack for us calling all of the destructors for
|
||||
// objects allocated on the stack.
|
||||
//
|
||||
// At a setjmp call, the basic block is split and the setjmp removed.
|
||||
// The calls in a function that have a setjmp are converted to invoke
|
||||
// where the except part checks to see if it's a longjmp exception and,
|
||||
// if so, if it's handled in the function. If it is, then it gets the
|
||||
// value returned by the longjmp and goes to where the basic block was
|
||||
// split. Invoke instructions are handled in a similar fashion with the
|
||||
// original except block being executed if it isn't a longjmp except
|
||||
// that is handled by that function.
|
||||
//
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
// FIXME: This pass doesn't deal with PHI statements just yet. That is,
|
||||
// we expect this to occur before SSAification is done. This would seem
|
||||
// to make sense, but in general, it might be a good idea to make this
|
||||
// pass invokable via the "opt" command at will.
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
#include "llvm/Constants.h"
|
||||
#include "llvm/DerivedTypes.h"
|
||||
#include "llvm/Instructions.h"
|
||||
#include "llvm/Intrinsics.h"
|
||||
#include "llvm/Module.h"
|
||||
#include "llvm/Pass.h"
|
||||
#include "llvm/Support/InstIterator.h"
|
||||
#include "llvm/Support/InstVisitor.h"
|
||||
#include "Support/Statistic.h"
|
||||
#include "Support/StringExtras.h"
|
||||
#include "Support/VectorExtras.h"
|
||||
|
||||
#include <set>
|
||||
|
||||
namespace {
|
||||
Statistic<> LongJmpsTransformed("lowersetjmp",
|
||||
"Number of longjmps transformed");
|
||||
Statistic<> SetJmpsTransformed("lowersetjmp",
|
||||
"Number of setjmps transformed");
|
||||
|
||||
//===--------------------------------------------------------------------===//
|
||||
// LowerSetJmp pass implementation. This is subclassed from the "Pass"
|
||||
// class because it works on a module as a whole, not a function at a
|
||||
// time.
|
||||
|
||||
class LowerSetJmp : public Pass,
|
||||
public InstVisitor<LowerSetJmp> {
|
||||
// LLVM library functions...
|
||||
Function* InitSJMap; // __llvm_sjljeh_init_setjmpmap
|
||||
Function* DestroySJMap; // __llvm_sjljeh_destroy_setjmpmap
|
||||
Function* AddSJToMap; // __llvm_sjljeh_add_setjmp_to_map
|
||||
Function* ThrowLongJmp; // __llvm_sjljeh_throw_longjmp
|
||||
Function* TryCatchLJ; // __llvm_sjljeh_try_catching_longjmp_exception
|
||||
Function* IsLJException; // __llvm_sjljeh_is_longjmp_exception
|
||||
Function* GetLJValue; // __llvm_sjljeh_get_longjmp_value
|
||||
|
||||
typedef std::pair<SwitchInst*, CallInst*> SwitchValuePair;
|
||||
|
||||
// The setjmp map is going to hold information about which setjmps
|
||||
// were called (each setjmp gets its own number) and with which
|
||||
// buffer it was called.
|
||||
std::map<Function*, AllocaInst*> SJMap;
|
||||
|
||||
// The rethrow basic block map holds the basic block to branch to if
|
||||
// the exception isn't handled in the current function and needs to
|
||||
// be rethrown.
|
||||
std::map<const Function*, BasicBlock*> RethrowBBMap;
|
||||
|
||||
// The preliminary basic block map holds a basic block that grabs the
|
||||
// exception and determines if it's handled by the current function.
|
||||
std::map<const Function*, BasicBlock*> PrelimBBMap;
|
||||
|
||||
// The switch/value map holds a switch inst/call inst pair. The
|
||||
// switch inst controls which handler (if any) gets called and the
|
||||
// value is the value returned to that handler by the call to
|
||||
// __llvm_sjljeh_get_longjmp_value.
|
||||
std::map<const Function*, SwitchValuePair> SwitchValMap;
|
||||
|
||||
// A map of which setjmps we've seen so far in a function.
|
||||
std::map<const Function*, unsigned> SetJmpIDMap;
|
||||
|
||||
AllocaInst* GetSetJmpMap(Function* Func);
|
||||
BasicBlock* GetRethrowBB(Function* Func);
|
||||
SwitchValuePair GetSJSwitch(Function* Func, BasicBlock* Rethrow);
|
||||
|
||||
void TransformLongJmpCall(CallInst* Inst);
|
||||
void TransformSetJmpCall(CallInst* Inst);
|
||||
|
||||
bool IsTransformableFunction(const std::string& Name);
|
||||
public:
|
||||
void visitCallInst(CallInst& CI);
|
||||
void visitInvokeInst(InvokeInst& II);
|
||||
void visitReturnInst(ReturnInst& RI);
|
||||
void visitUnwindInst(UnwindInst& UI);
|
||||
|
||||
bool run(Module& M);
|
||||
bool doInitialization(Module& M);
|
||||
};
|
||||
|
||||
RegisterOpt<LowerSetJmp> X("lowersetjmp", "Lower Set Jump");
|
||||
} // end anonymous namespace
|
||||
|
||||
// run - Run the transformation on the program. We grab the function
|
||||
// prototypes for longjmp and setjmp. If they are used in the program,
|
||||
// then we can go directly to the places they're at and transform them.
|
||||
bool LowerSetJmp::run(Module& M)
|
||||
{
|
||||
bool Changed = false;
|
||||
|
||||
// These are what the functions are called.
|
||||
Function* SetJmp = M.getNamedFunction("llvm.setjmp");
|
||||
Function* LongJmp = M.getNamedFunction("llvm.longjmp");
|
||||
|
||||
// This program doesn't have longjmp and setjmp calls.
|
||||
if ((!LongJmp || LongJmp->use_empty()) &&
|
||||
(!SetJmp || SetJmp->use_empty())) return false;
|
||||
|
||||
// Initialize some values and functions we'll need to transform the
|
||||
// setjmp/longjmp functions.
|
||||
doInitialization(M);
|
||||
|
||||
if (SetJmp)
|
||||
while (!SetJmp->use_empty()) {
|
||||
assert(isa<CallInst>(SetJmp->use_back()) &&
|
||||
"User of setjmp intrinsic not a call?");
|
||||
TransformSetJmpCall(cast<CallInst>(SetJmp->use_back()));
|
||||
Changed = true;
|
||||
}
|
||||
|
||||
if (LongJmp)
|
||||
while (!LongJmp->use_empty()) {
|
||||
assert(isa<CallInst>(LongJmp->use_back()) &&
|
||||
"User of longjmp intrinsic not a call?");
|
||||
TransformLongJmpCall(cast<CallInst>(LongJmp->use_back()));
|
||||
Changed = true;
|
||||
}
|
||||
|
||||
// Now go through the affected functions and convert calls and invokes
|
||||
// to new invokes...
|
||||
for (std::map<Function*, AllocaInst*>::iterator
|
||||
B = SJMap.begin(), E = SJMap.end(); B != E; ++B) {
|
||||
Function* F = B->first;
|
||||
for (Function::iterator BB = F->begin(), BE = F->end(); BB != BE; ++BB)
|
||||
for (BasicBlock::iterator IB = BB->begin(), IE = BB->end(); IB != IE; ) {
|
||||
visit(*IB++);
|
||||
if (IB != BB->end() && IB->getParent() != BB)
|
||||
break; // The next instruction got moved to a different block!
|
||||
}
|
||||
}
|
||||
|
||||
SJMap.clear();
|
||||
RethrowBBMap.clear();
|
||||
PrelimBBMap.clear();
|
||||
SwitchValMap.clear();
|
||||
SetJmpIDMap.clear();
|
||||
|
||||
return Changed;
|
||||
}
|
||||
|
||||
// doInitialization - For the lower long/setjmp pass, this ensures that a
|
||||
// module contains a declaration for the intrisic functions we are going
|
||||
// to call to convert longjmp and setjmp calls.
|
||||
//
|
||||
// This function is always successful, unless it isn't.
|
||||
bool LowerSetJmp::doInitialization(Module& M)
|
||||
{
|
||||
const Type *SBPTy = PointerType::get(Type::SByteTy);
|
||||
const Type *SBPPTy = PointerType::get(SBPTy);
|
||||
|
||||
// N.B. See llvm/runtime/GCCLibraries/libexception/SJLJ-Exception.h for
|
||||
// a description of the following library functions.
|
||||
|
||||
// void __llvm_sjljeh_init_setjmpmap(void**)
|
||||
InitSJMap = M.getOrInsertFunction("__llvm_sjljeh_init_setjmpmap",
|
||||
Type::VoidTy, SBPPTy, 0);
|
||||
// void __llvm_sjljeh_destroy_setjmpmap(void**)
|
||||
DestroySJMap = M.getOrInsertFunction("__llvm_sjljeh_destroy_setjmpmap",
|
||||
Type::VoidTy, SBPPTy, 0);
|
||||
|
||||
// void __llvm_sjljeh_add_setjmp_to_map(void**, void*, unsigned)
|
||||
AddSJToMap = M.getOrInsertFunction("__llvm_sjljeh_add_setjmp_to_map",
|
||||
Type::VoidTy, SBPPTy, SBPTy,
|
||||
Type::UIntTy, 0);
|
||||
|
||||
// void __llvm_sjljeh_throw_longjmp(int*, int)
|
||||
ThrowLongJmp = M.getOrInsertFunction("__llvm_sjljeh_throw_longjmp",
|
||||
Type::VoidTy, SBPTy, Type::IntTy, 0);
|
||||
|
||||
// unsigned __llvm_sjljeh_try_catching_longjmp_exception(void **)
|
||||
TryCatchLJ =
|
||||
M.getOrInsertFunction("__llvm_sjljeh_try_catching_longjmp_exception",
|
||||
Type::UIntTy, SBPPTy, 0);
|
||||
|
||||
// bool __llvm_sjljeh_is_longjmp_exception()
|
||||
IsLJException = M.getOrInsertFunction("__llvm_sjljeh_is_longjmp_exception",
|
||||
Type::BoolTy, 0);
|
||||
|
||||
// int __llvm_sjljeh_get_longjmp_value()
|
||||
GetLJValue = M.getOrInsertFunction("__llvm_sjljeh_get_longjmp_value",
|
||||
Type::IntTy, 0);
|
||||
return true;
|
||||
}
|
||||
|
||||
// IsTransformableFunction - Return true if the function name isn't one
|
||||
// of the ones we don't want transformed. Currently, don't transform any
|
||||
// "llvm.{setjmp,longjmp}" functions and none of the setjmp/longjmp error
|
||||
// handling functions (beginning with __llvm_sjljeh_...they don't throw
|
||||
// exceptions).
|
||||
bool LowerSetJmp::IsTransformableFunction(const std::string& Name)
|
||||
{
|
||||
std::string SJLJEh("__llvm_sjljeh");
|
||||
|
||||
if (Name.size() > SJLJEh.size()) {
|
||||
std::string N(Name.begin(), Name.begin() + SJLJEh.size());
|
||||
return N != SJLJEh;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
// TransformLongJmpCall - Transform a longjmp call into a call to the
|
||||
// internal __llvm_sjljeh_throw_longjmp function. It then takes care of
|
||||
// throwing the exception for us.
|
||||
void LowerSetJmp::TransformLongJmpCall(CallInst* Inst)
|
||||
{
|
||||
const Type* SBPTy = PointerType::get(Type::SByteTy);
|
||||
|
||||
// Create the call to "__llvm_sjljeh_throw_longjmp". This takes the
|
||||
// same parameters as "longjmp", except that the buffer is cast to a
|
||||
// char*. It returns "void", so it doesn't need to replace any of
|
||||
// Inst's uses and doesn't get a name.
|
||||
CastInst* CI = new CastInst(Inst->getOperand(1), SBPTy, "LJBuf", Inst);
|
||||
new CallInst(ThrowLongJmp, make_vector<Value*>(CI, Inst->getOperand(2), 0),
|
||||
"", Inst);
|
||||
|
||||
SwitchValuePair& SVP = SwitchValMap[Inst->getParent()->getParent()];
|
||||
|
||||
// If the function has a setjmp call in it (they are transformed first)
|
||||
// we should branch to the basic block that determines if this longjmp
|
||||
// is applicable here. Otherwise, issue an unwind.
|
||||
if (SVP.first)
|
||||
new BranchInst(SVP.first->getParent(), Inst);
|
||||
else
|
||||
new UnwindInst(Inst);
|
||||
|
||||
// Remove all insts after the branch/unwind inst.
|
||||
Inst->getParent()->getInstList().erase(Inst,
|
||||
Inst->getParent()->getInstList().end());
|
||||
|
||||
++LongJmpsTransformed;
|
||||
}
|
||||
|
||||
// GetSetJmpMap - Retrieve (create and initialize, if necessary) the
|
||||
// setjmp map. This map is going to hold information about which setjmps
|
||||
// were called (each setjmp gets its own number) and with which buffer it
|
||||
// was called. There can be only one!
|
||||
AllocaInst* LowerSetJmp::GetSetJmpMap(Function* Func)
|
||||
{
|
||||
if (SJMap[Func]) return SJMap[Func];
|
||||
|
||||
// Insert the setjmp map initialization before the first instruction in
|
||||
// the function.
|
||||
Instruction* Inst = Func->getEntryNode().begin();
|
||||
assert(Inst && "Couldn't find even ONE instruction in entry block!");
|
||||
|
||||
// Fill in the alloca and call to initialize the SJ map.
|
||||
const Type *SBPTy = PointerType::get(Type::SByteTy);
|
||||
AllocaInst* Map = new AllocaInst(SBPTy, 0, "SJMap", Inst);
|
||||
new CallInst(InitSJMap, make_vector<Value*>(Map, 0), "", Inst);
|
||||
return SJMap[Func] = Map;
|
||||
}
|
||||
|
||||
// GetRethrowBB - Only one rethrow basic block is needed per function.
|
||||
// If this is a longjmp exception but not handled in this block, this BB
|
||||
// performs the rethrow.
|
||||
BasicBlock* LowerSetJmp::GetRethrowBB(Function* Func)
|
||||
{
|
||||
if (RethrowBBMap[Func]) return RethrowBBMap[Func];
|
||||
|
||||
// The basic block we're going to jump to if we need to rethrow the
|
||||
// exception.
|
||||
BasicBlock* Rethrow = new BasicBlock("RethrowExcept", Func);
|
||||
BasicBlock::InstListType& RethrowBlkIL = Rethrow->getInstList();
|
||||
|
||||
// Fill in the "Rethrow" BB with a call to rethrow the exception. This
|
||||
// is the last instruction in the BB since at this point the runtime
|
||||
// should exit this function and go to the next function.
|
||||
RethrowBlkIL.push_back(new UnwindInst());
|
||||
return RethrowBBMap[Func] = Rethrow;
|
||||
}
|
||||
|
||||
// GetSJSwitch - Return the switch statement that controls which handler
|
||||
// (if any) gets called and the value returned to that handler.
|
||||
LowerSetJmp::SwitchValuePair LowerSetJmp::GetSJSwitch(Function* Func,
|
||||
BasicBlock* Rethrow)
|
||||
{
|
||||
if (SwitchValMap[Func].first) return SwitchValMap[Func];
|
||||
|
||||
BasicBlock* LongJmpPre = new BasicBlock("LongJmpBlkPre", Func);
|
||||
BasicBlock::InstListType& LongJmpPreIL = LongJmpPre->getInstList();
|
||||
|
||||
// Keep track of the preliminary basic block for some of the other
|
||||
// transformations.
|
||||
PrelimBBMap[Func] = LongJmpPre;
|
||||
|
||||
// Grab the exception.
|
||||
CallInst* Cond = new
|
||||
CallInst(IsLJException, std::vector<Value*>(), "IsLJExcept");
|
||||
LongJmpPreIL.push_back(Cond);
|
||||
|
||||
// The "decision basic block" gets the number associated with the
|
||||
// setjmp call returning to switch on and the value returned by
|
||||
// longjmp.
|
||||
BasicBlock* DecisionBB = new BasicBlock("LJDecisionBB", Func);
|
||||
BasicBlock::InstListType& DecisionBBIL = DecisionBB->getInstList();
|
||||
|
||||
LongJmpPreIL.push_back(new BranchInst(DecisionBB, Rethrow, Cond));
|
||||
|
||||
// Fill in the "decision" basic block.
|
||||
CallInst* LJVal = new CallInst(GetLJValue, std::vector<Value*>(), "LJVal");
|
||||
DecisionBBIL.push_back(LJVal);
|
||||
CallInst* SJNum = new
|
||||
CallInst(TryCatchLJ, make_vector<Value*>(GetSetJmpMap(Func), 0), "SJNum");
|
||||
DecisionBBIL.push_back(SJNum);
|
||||
|
||||
SwitchInst* SI = new SwitchInst(SJNum, Rethrow);
|
||||
DecisionBBIL.push_back(SI);
|
||||
return SwitchValMap[Func] = SwitchValuePair(SI, LJVal);
|
||||
}
|
||||
|
||||
// TransformSetJmpCall - The setjmp call is a bit trickier to transform.
|
||||
// We're going to convert all setjmp calls to nops. Then all "call" and
|
||||
// "invoke" instructions in the function are converted to "invoke" where
|
||||
// the "except" branch is used when returning from a longjmp call.
|
||||
void LowerSetJmp::TransformSetJmpCall(CallInst* Inst)
|
||||
{
|
||||
BasicBlock* ABlock = Inst->getParent();
|
||||
Function* Func = ABlock->getParent();
|
||||
|
||||
// Add this setjmp to the setjmp map.
|
||||
const Type* SBPTy = PointerType::get(Type::SByteTy);
|
||||
CastInst* BufPtr = new CastInst(Inst->getOperand(1), SBPTy, "SBJmpBuf", Inst);
|
||||
new CallInst(AddSJToMap,
|
||||
make_vector<Value*>(GetSetJmpMap(Func), BufPtr,
|
||||
ConstantUInt::get(Type::UIntTy,
|
||||
SetJmpIDMap[Func]++), 0),
|
||||
"", Inst);
|
||||
|
||||
// FIXME: This is a nasty piece of code. We want the jump buffer to
|
||||
// dominate all uses. However, we're doing unnatural things to the CFG
|
||||
// which cause this dominance to be lost. The only way to guarantee we
|
||||
// get it back is to place where the jump buffer is being allocated
|
||||
// into the entry block. That's what this code does. The alloca for the
|
||||
// jump buffer is followed by a getelementptr call.
|
||||
if (GetElementPtrInst* GEP = dyn_cast<GetElementPtrInst>(Inst->getOperand(1)))
|
||||
if (GEP->use_size() > 1) {
|
||||
if (AllocaInst* AI = dyn_cast<AllocaInst>(GEP->getPointerOperand())) {
|
||||
BasicBlock& Entry = Func->getEntryNode();
|
||||
BasicBlock::InstListType& EntryIL = Entry.getInstList();
|
||||
|
||||
Instruction* NewAI = AI->clone();
|
||||
Instruction* NewGEP = GEP->clone();
|
||||
NewAI->setName(AI->getName());
|
||||
NewGEP->setName(GEP->getName());
|
||||
EntryIL.push_front(NewGEP);
|
||||
EntryIL.push_front(NewAI);
|
||||
GEP->replaceAllUsesWith(NewGEP);
|
||||
AI->replaceAllUsesWith(NewAI);
|
||||
}
|
||||
}
|
||||
|
||||
// Change the setjmp call into a branch statement. We'll remove the
|
||||
// setjmp call in a little bit. No worries.
|
||||
BasicBlock* SetJmpContBlock = ABlock->splitBasicBlock(Inst);
|
||||
assert(SetJmpContBlock && "Couldn't split setjmp BB!!");
|
||||
|
||||
SetJmpContBlock->setName("SetJmpContBlock");
|
||||
|
||||
// Reposition the split BB in the BB list to make things tidier.
|
||||
Func->getBasicBlockList().remove(SetJmpContBlock);
|
||||
Func->getBasicBlockList().insert(++Function::iterator(ABlock),
|
||||
SetJmpContBlock);
|
||||
|
||||
// This PHI node will be in the new block created from the
|
||||
// splitBasicBlock call.
|
||||
PHINode* PHI = new PHINode(Type::IntTy, "SetJmpReturn", Inst);
|
||||
|
||||
// Coming from a call to setjmp, the return is 0.
|
||||
PHI->addIncoming(ConstantInt::getNullValue(Type::IntTy), ABlock);
|
||||
|
||||
// Add the case for this setjmp's number...
|
||||
SwitchValuePair SVP = GetSJSwitch(Func, GetRethrowBB(Func));
|
||||
SVP.first->addCase(ConstantUInt::get(Type::UIntTy, SetJmpIDMap[Func] - 1),
|
||||
SetJmpContBlock);
|
||||
|
||||
// Value coming from the handling of the exception.
|
||||
PHI->addIncoming(SVP.second, SVP.second->getParent());
|
||||
|
||||
// Replace all uses of this instruction with the PHI node created by
|
||||
// the eradication of setjmp.
|
||||
Inst->replaceAllUsesWith(PHI);
|
||||
Inst->getParent()->getInstList().erase(Inst);
|
||||
|
||||
++SetJmpsTransformed;
|
||||
}
|
||||
|
||||
// visitCallInst - This converts all LLVM call instructions into invoke
|
||||
// instructions. The except part of the invoke goes to the "LongJmpBlkPre"
|
||||
// that grabs the exception and proceeds to determine if it's a longjmp
|
||||
// exception or not.
|
||||
void LowerSetJmp::visitCallInst(CallInst& CI)
|
||||
{
|
||||
if (CI.getCalledFunction())
|
||||
if (!IsTransformableFunction(CI.getCalledFunction()->getName()) ||
|
||||
CI.getCalledFunction()->isIntrinsic()) return;
|
||||
|
||||
BasicBlock* OldBB = CI.getParent();
|
||||
BasicBlock* NewBB = OldBB->splitBasicBlock(CI);
|
||||
assert(NewBB && "Couldn't split BB of \"call\" instruction!!");
|
||||
NewBB->setName("Call2Invoke");
|
||||
|
||||
// Reposition the split BB in the BB list to make things tidier.
|
||||
Function* Func = OldBB->getParent();
|
||||
Func->getBasicBlockList().remove(NewBB);
|
||||
Func->getBasicBlockList().insert(++Function::iterator(OldBB), NewBB);
|
||||
|
||||
// Construct the new "invoke" instruction.
|
||||
TerminatorInst* Term = OldBB->getTerminator();
|
||||
std::vector<Value*> Params(CI.op_begin() + 1, CI.op_end());
|
||||
InvokeInst* II = new
|
||||
InvokeInst(CI.getCalledValue(), NewBB, PrelimBBMap[Func],
|
||||
Params, CI.getName(), Term);
|
||||
|
||||
// Replace the old call inst with the invoke inst and remove the call.
|
||||
CI.replaceAllUsesWith(II);
|
||||
CI.getParent()->getInstList().erase(&CI);
|
||||
|
||||
// The old terminator is useless now that we have the invoke inst.
|
||||
Term->getParent()->getInstList().erase(Term);
|
||||
}
|
||||
|
||||
// visitInvokeInst - Converting the "invoke" instruction is fairly
|
||||
// straight-forward. The old exception part is replaced by a query asking
|
||||
// if this is a longjmp exception. If it is, then it goes to the longjmp
|
||||
// exception blocks. Otherwise, control is passed the old exception.
|
||||
void LowerSetJmp::visitInvokeInst(InvokeInst& II)
|
||||
{
|
||||
if (II.getCalledFunction())
|
||||
if (!IsTransformableFunction(II.getCalledFunction()->getName()) ||
|
||||
II.getCalledFunction()->isIntrinsic()) return;
|
||||
|
||||
Function* Func = II.getParent()->getParent();
|
||||
|
||||
BasicBlock* NormalBB = II.getNormalDest();
|
||||
BasicBlock* ExceptBB = II.getExceptionalDest();
|
||||
|
||||
BasicBlock* NewExceptBB = new BasicBlock("InvokeExcept", Func);
|
||||
BasicBlock::InstListType& InstList = NewExceptBB->getInstList();
|
||||
|
||||
// If this is a longjmp exception, then branch to the preliminary BB of
|
||||
// the longjmp exception handling. Otherwise, go to the old exception.
|
||||
CallInst* IsLJExcept = new
|
||||
CallInst(IsLJException, std::vector<Value*>(), "IsLJExcept");
|
||||
InstList.push_back(IsLJExcept);
|
||||
|
||||
BranchInst* BR = new BranchInst(PrelimBBMap[Func], ExceptBB, IsLJExcept);
|
||||
InstList.push_back(BR);
|
||||
|
||||
II.setExceptionalDest(NewExceptBB);
|
||||
}
|
||||
|
||||
// visitReturnInst - We want to destroy the setjmp map upon exit from the
|
||||
// function.
|
||||
void LowerSetJmp::visitReturnInst(ReturnInst& RI)
|
||||
{
|
||||
Function* Func = RI.getParent()->getParent();
|
||||
new CallInst(DestroySJMap, make_vector<Value*>(GetSetJmpMap(Func), 0),
|
||||
"", &RI);
|
||||
}
|
||||
|
||||
// visitUnwindInst - We want to destroy the setjmp map upon exit from the
|
||||
// function.
|
||||
void LowerSetJmp::visitUnwindInst(UnwindInst& UI)
|
||||
{
|
||||
Function* Func = UI.getParent()->getParent();
|
||||
new CallInst(DestroySJMap, make_vector<Value*>(GetSetJmpMap(Func), 0),
|
||||
"", &UI);
|
||||
}
|
||||
|
||||
Pass* createLowerSetJmpPass()
|
||||
{
|
||||
return new LowerSetJmp();
|
||||
}
|
Loading…
Reference in New Issue
Block a user