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mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-22 18:54:02 +01:00

[WinEH] Add codegen support for cleanuppad and cleanupret

All of the complexity is in cleanupret, and it mostly follows the same
codepaths as catchret, except it doesn't take a return value in RAX.

This small example now compiles and executes successfully on win32:
  extern "C" int printf(const char *, ...) noexcept;
  struct Dtor {
    ~Dtor() { printf("~Dtor\n"); }
  };
  void has_cleanup() {
    Dtor o;
    throw 42;
  }
  int main() {
    try {
      has_cleanup();
    } catch (int) {
      printf("caught it\n");
    }
  }

Don't try to put the cleanup in the same function as the catch, or Bad
Things will happen.

llvm-svn: 247219
This commit is contained in:
Reid Kleckner 2015-09-10 00:25:23 +00:00
parent ad09731a88
commit b5753fd45f
13 changed files with 130 additions and 71 deletions

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@ -591,8 +591,13 @@ namespace ISD {
/// take a chain as input and return a chain.
EH_LABEL,
/// CATCHRET - Represents a return from a catch block funclet. Used for
/// MSVC compatible exception handling. Takes a chain operand and a
/// destination basic block operand.
CATCHRET,
/// CLEANUPRET - Represents a return from a cleanup block funclet. Used for
/// MSVC compatible exception handling. Takes only a chain operand.
CLEANUPRET,
/// STACKSAVE - STACKSAVE has one operand, an input chain. It produces a

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@ -116,14 +116,14 @@ void parseEHActions(const IntrinsicInst *II,
// The following structs respresent the .xdata for functions using C++
// exceptions on Windows.
struct WinEHUnwindMapEntry {
int ToState;
const Value *Cleanup;
};
typedef PointerUnion<const BasicBlock *, MachineBasicBlock *> MBBOrBasicBlock;
typedef PointerUnion<const Value *, MachineBasicBlock *> ValueOrMBB;
struct WinEHUnwindMapEntry {
int ToState;
ValueOrMBB Cleanup;
};
/// Similar to WinEHUnwindMapEntry, but supports SEH filters.
struct SEHUnwindMapEntry {
/// If unwinding continues through this handler, transition to the handler at

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@ -316,10 +316,11 @@ void WinException::emitCSpecificHandlerTable(const MachineFunction *MF) {
/// Retreive the MCSymbol for a GlobalValue or MachineBasicBlock. GlobalValues
/// are used in the old WinEH scheme, and they will be removed eventually.
static MCSymbol *getMCSymbolForMBBOrGV(AsmPrinter *Asm, ValueOrMBB Handler) {
if (!Handler)
return nullptr;
if (Handler.is<MachineBasicBlock *>())
return Handler.get<MachineBasicBlock *>()->getSymbol();
else
return Asm->getSymbol(cast<GlobalValue>(Handler.get<const Value *>()));
return Asm->getSymbol(cast<GlobalValue>(Handler.get<const Value *>()));
}
void WinException::emitCXXFrameHandler3Table(const MachineFunction *MF) {
@ -404,8 +405,9 @@ void WinException::emitCXXFrameHandler3Table(const MachineFunction *MF) {
if (UnwindMapXData) {
OS.EmitLabel(UnwindMapXData);
for (const WinEHUnwindMapEntry &UME : FuncInfo.UnwindMap) {
OS.EmitIntValue(UME.ToState, 4); // ToState
OS.EmitValue(create32bitRef(UME.Cleanup), 4); // Action
MCSymbol *CleanupSym = getMCSymbolForMBBOrGV(Asm, UME.Cleanup);
OS.EmitIntValue(UME.ToState, 4); // ToState
OS.EmitValue(create32bitRef(CleanupSym), 4); // Action
}
}

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@ -223,8 +223,6 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf,
assert(&*BB->begin() == I &&
"WinEHPrepare failed to remove PHIs from imaginary BBs");
continue;
} else if (!isa<LandingPadInst>(I)) {
llvm_unreachable("unhandled EH pad in MBB graph");
}
}
@ -269,7 +267,7 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf,
SmallVector<const LandingPadInst *, 4> LPads;
for (BB = Fn->begin(); BB != EB; ++BB) {
const Instruction *FNP = BB->getFirstNonPHI();
if (BB->isEHPad() && !isa<CatchPadInst>(FNP) && !isa<CatchEndPadInst>(FNP))
if (BB->isEHPad() && MBBMap.count(BB))
MBBMap[BB]->setIsEHPad();
if (const auto *LPI = dyn_cast<LandingPadInst>(FNP))
LPads.push_back(LPI);
@ -289,24 +287,27 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf,
// Calculate state numbers if we haven't already.
WinEHFuncInfo &EHInfo = MMI.getWinEHFuncInfo(&fn);
if (Personality == EHPersonality::MSVC_CXX) {
const Function *WinEHParentFn = MMI.getWinEHParent(&fn);
const Function *WinEHParentFn = MMI.getWinEHParent(&fn);
if (Personality == EHPersonality::MSVC_CXX)
calculateWinCXXEHStateNumbers(WinEHParentFn, EHInfo);
} else {
const Function *WinEHParentFn = MMI.getWinEHParent(&fn);
else
calculateSEHStateNumbers(WinEHParentFn, EHInfo);
// Map all BB references in the WinEH data to MBBs.
for (WinEHTryBlockMapEntry &TBME : EHInfo.TryBlockMap)
for (WinEHHandlerType &H : TBME.HandlerArray)
if (const auto *BB =
dyn_cast<BasicBlock>(H.Handler.get<const Value *>()))
H.Handler = MBBMap[BB];
for (WinEHUnwindMapEntry &UME : EHInfo.UnwindMap)
if (UME.Cleanup)
if (const auto *BB = dyn_cast<BasicBlock>(UME.Cleanup.get<const Value *>()))
UME.Cleanup = MBBMap[BB];
for (SEHUnwindMapEntry &UME : EHInfo.SEHUnwindMap) {
const BasicBlock *BB = UME.Handler.get<const BasicBlock *>();
UME.Handler = MBBMap[BB];
}
// Map all BB references in the EH data to MBBs.
for (WinEHTryBlockMapEntry &TBME : EHInfo.TryBlockMap)
for (WinEHHandlerType &H : TBME.HandlerArray)
if (const auto *BB =
dyn_cast<BasicBlock>(H.Handler.get<const Value *>()))
H.Handler = MBBMap[BB];
for (SEHUnwindMapEntry &UME : EHInfo.SEHUnwindMap) {
const BasicBlock *BB = UME.Handler.get<const BasicBlock *>();
UME.Handler = MBBMap[BB];
}
// If there's an explicit EH registration node on the stack, record its
// frame index.
if (EHInfo.EHRegNode && EHInfo.EHRegNode->getParent()->getParent() == Fn) {

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@ -1165,9 +1165,8 @@ void SelectionDAGBuilder::visitCatchPad(const CatchPadInst &I) {
void SelectionDAGBuilder::visitCatchRet(const CatchReturnInst &I) {
// Update machine-CFG edge.
MachineBasicBlock *PadMBB = FuncInfo.MBB;
MachineBasicBlock *TargetMBB = FuncInfo.MBBMap[I.getSuccessor()];
PadMBB->addSuccessor(TargetMBB);
FuncInfo.MBB->addSuccessor(TargetMBB);
// Create the terminator node.
SDValue Ret = DAG.getNode(ISD::CATCHRET, getCurSDLoc(), MVT::Other,
@ -1180,11 +1179,64 @@ void SelectionDAGBuilder::visitCatchEndPad(const CatchEndPadInst &I) {
}
void SelectionDAGBuilder::visitCleanupPad(const CleanupPadInst &CPI) {
report_fatal_error("visitCleanupPad not yet implemented!");
// Don't emit any special code for the cleanuppad instruction. It just marks
// the start of a funclet.
FuncInfo.MBB->setIsEHFuncletEntry();
}
/// When an invoke or a cleanupret unwinds to the next EH pad, there are
/// many places it could ultimately go. In the IR, we have a single unwind
/// destination, but in the machine CFG, we enumerate all the possible blocks.
/// This function skips over imaginary basic blocks that hold catchpad,
/// terminatepad, or catchendpad instructions, and finds all the "real" machine
/// basic block destinations.
static void
findUnwindDestinations(FunctionLoweringInfo &FuncInfo,
const BasicBlock *EHPadBB,
SmallVectorImpl<MachineBasicBlock *> &UnwindDests) {
bool IsMSVCCXX = classifyEHPersonality(FuncInfo.Fn->getPersonalityFn()) ==
EHPersonality::MSVC_CXX;
while (EHPadBB) {
const Instruction *Pad = EHPadBB->getFirstNonPHI();
if (isa<LandingPadInst>(Pad)) {
// Stop on landingpads. They are not funclets.
UnwindDests.push_back(FuncInfo.MBBMap[EHPadBB]);
break;
} else if (isa<CleanupPadInst>(Pad) || isa<LandingPadInst>(Pad)) {
// Stop on cleanup pads. Cleanups are always funclet entries for all known
// personalities.
UnwindDests.push_back(FuncInfo.MBBMap[EHPadBB]);
UnwindDests.back()->setIsEHFuncletEntry();
break;
} else if (const auto *CPI = dyn_cast<CatchPadInst>(Pad)) {
// Add the catchpad handler to the possible destinations.
UnwindDests.push_back(FuncInfo.MBBMap[CPI->getNormalDest()]);
// In MSVC C++, catchblocks are funclets and need prologues.
if (IsMSVCCXX)
UnwindDests.back()->setIsEHFuncletEntry();
EHPadBB = CPI->getUnwindDest();
} else if (const auto *CEPI = dyn_cast<CatchEndPadInst>(Pad)) {
EHPadBB = CEPI->getUnwindDest();
} else if (const auto *CEPI = dyn_cast<CleanupEndPadInst>(Pad)) {
EHPadBB = CEPI->getUnwindDest();
}
}
}
void SelectionDAGBuilder::visitCleanupRet(const CleanupReturnInst &I) {
report_fatal_error("visitCleanupRet not yet implemented!");
// Update successor info.
// FIXME: The weights for catchpads will be wrong.
SmallVector<MachineBasicBlock *, 1> UnwindDests;
findUnwindDestinations(FuncInfo, I.getUnwindDest(), UnwindDests);
for (MachineBasicBlock *UnwindDest : UnwindDests) {
UnwindDest->setIsEHPad();
addSuccessorWithWeight(FuncInfo.MBB, UnwindDest);
}
// Create the terminator node.
SDValue Ret =
DAG.getNode(ISD::CLEANUPRET, getCurSDLoc(), MVT::Other, getControlRoot());
DAG.setRoot(Ret);
}
void SelectionDAGBuilder::visitCleanupEndPad(const CleanupEndPadInst &I) {
@ -2020,37 +2072,8 @@ void SelectionDAGBuilder::visitInvoke(const InvokeInst &I) {
CopyToExportRegsIfNeeded(&I);
}
// Stop when we hit a pad that generates real code or we unwind to caller.
// Catchpads are conditional branches that add real MBB destinations and
// continue the loop. EH "end" pads are not real BBs and simply continue.
SmallVector<MachineBasicBlock *, 1> UnwindDests;
bool IsMSVCCXX = classifyEHPersonality(FuncInfo.Fn->getPersonalityFn()) ==
EHPersonality::MSVC_CXX;
while (EHPadBB) {
const Instruction *Pad = EHPadBB->getFirstNonPHI();
if (isa<LandingPadInst>(Pad)) {
// Stop on landingpads. They are not funclets.
UnwindDests.push_back(FuncInfo.MBBMap[EHPadBB]);
break;
} else if (isa<CleanupPadInst>(Pad) || isa<LandingPadInst>(Pad)) {
// Stop on cleanup pads. Cleanups are always funclet entries for all known
// personalities.
UnwindDests.push_back(FuncInfo.MBBMap[EHPadBB]);
UnwindDests.back()->setIsEHFuncletEntry();
break;
} else if (const auto *CPI = dyn_cast<CatchPadInst>(Pad)) {
// Add the catchpad handler to the possible destinations.
UnwindDests.push_back(FuncInfo.MBBMap[CPI->getNormalDest()]);
// In MSVC C++, catchblocks are funclets and need prologues.
if (IsMSVCCXX)
UnwindDests.back()->setIsEHFuncletEntry();
EHPadBB = CPI->getUnwindDest();
} else if (const auto *CEPI = dyn_cast<CatchEndPadInst>(Pad)) {
EHPadBB = CEPI->getUnwindDest();
} else if (const auto *CEPI = dyn_cast<CleanupEndPadInst>(Pad)) {
EHPadBB = CEPI->getUnwindDest();
}
}
findUnwindDestinations(FuncInfo, EHPadBB, UnwindDests);
// Update successor info.
// FIXME: The weights for catchpads will be wrong.

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@ -3053,7 +3053,7 @@ static void calculateExplicitCXXStateNumbers(WinEHFuncInfo &FuncInfo,
}
static int addSEHHandler(WinEHFuncInfo &FuncInfo, int ParentState,
const Function *Filter, const BasicBlock *Handler) {
const Function *Filter, const BasicBlock *Handler) {
SEHUnwindMapEntry Entry;
Entry.ToState = ParentState;
Entry.Filter = Filter;

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@ -1030,6 +1030,8 @@ static bool isFuncletReturnInstr(MachineInstr *MI) {
switch (MI->getOpcode()) {
case X86::CATCHRET:
case X86::CATCHRET64:
case X86::CLEANUPRET:
case X86::CLEANUPRET64:
return true;
default:
return false;

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@ -418,6 +418,7 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
}
setOperationAction(ISD::EH_RETURN , MVT::Other, Custom);
setOperationAction(ISD::CATCHRET , MVT::Other, Custom);
setOperationAction(ISD::CLEANUPRET , MVT::Other, Custom);
// NOTE: EH_SJLJ_SETJMP/_LONGJMP supported here is NOT intended to support
// SjLj exception handling but a light-weight setjmp/longjmp replacement to
// support continuation, user-level threading, and etc.. As a result, no
@ -16889,20 +16890,26 @@ SDValue X86TargetLowering::LowerCATCHRET(SDValue Op, SelectionDAG &DAG) const {
return DAG.getNode(ISD::BR, DL, MVT::Other, Chain, Dest);
}
unsigned ReturnReg = (PtrVT == MVT::i64 ? X86::RAX : X86::EAX);
// Load the address of the destination block.
// FIXME: Do this without creating a BlockAddress.
MachineBasicBlock *DestMBB = cast<BasicBlockSDNode>(Dest)->getBasicBlock();
SDValue BlockPtr = DAG.getMCSymbol(DestMBB->getSymbol(), PtrVT);
unsigned WrapperKind =
Subtarget->isPICStyleRIPRel() ? X86ISD::WrapperRIP : X86ISD::Wrapper;
SDValue WrappedPtr = DAG.getNode(WrapperKind, DL, PtrVT, BlockPtr);
Chain = DAG.getCopyToReg(Chain, DL, ReturnReg, WrappedPtr);
BlockAddress *BA =
BlockAddress::get(const_cast<Function *>(MF.getFunction()),
const_cast<BasicBlock *>(DestMBB->getBasicBlock()));
DestMBB->setHasAddressTaken();
SDValue BlockPtr = DAG.getBlockAddress(BA, PtrVT);
Chain = DAG.getCopyToReg(Chain, DL, ReturnReg, BlockPtr);
return DAG.getNode(X86ISD::CATCHRET, DL, MVT::Other, Chain,
DAG.getRegister(ReturnReg, PtrVT));
}
SDValue X86TargetLowering::LowerCLEANUPRET(SDValue Op, SelectionDAG &DAG) const {
return DAG.getNode(X86ISD::CLEANUPRET, SDLoc(Op), MVT::Other,
Op.getOperand(0));
}
SDValue X86TargetLowering::lowerEH_SJLJ_SETJMP(SDValue Op,
SelectionDAG &DAG) const {
SDLoc DL(Op);
@ -19142,6 +19149,7 @@ SDValue X86TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
return LowerFRAME_TO_ARGS_OFFSET(Op, DAG);
case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
case ISD::EH_RETURN: return LowerEH_RETURN(Op, DAG);
case ISD::CLEANUPRET: return LowerCLEANUPRET(Op, DAG);
case ISD::CATCHRET: return LowerCATCHRET(Op, DAG);
case ISD::EH_SJLJ_SETJMP: return lowerEH_SJLJ_SETJMP(Op, DAG);
case ISD::EH_SJLJ_LONGJMP: return lowerEH_SJLJ_LONGJMP(Op, DAG);
@ -19480,6 +19488,7 @@ const char *X86TargetLowering::getTargetNodeName(unsigned Opcode) const {
case X86ISD::EH_SJLJ_LONGJMP: return "X86ISD::EH_SJLJ_LONGJMP";
case X86ISD::EH_RETURN: return "X86ISD::EH_RETURN";
case X86ISD::CATCHRET: return "X86ISD::CATCHRET";
case X86ISD::CLEANUPRET: return "X86ISD::CLEANUPRET";
case X86ISD::TC_RETURN: return "X86ISD::TC_RETURN";
case X86ISD::FNSTCW16m: return "X86ISD::FNSTCW16m";
case X86ISD::FNSTSW16r: return "X86ISD::FNSTSW16r";

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@ -268,8 +268,14 @@ namespace llvm {
// Exception Handling helpers.
EH_RETURN,
// CATCHRET - Represents a return from a catch block funclet. Used for
// MSVC compatible exception handling. Takes a chain operand and RAX.
CATCHRET,
// CLEANUPRET - Represents a return from a cleanup block funclet. Used
// for MSVC compatible exception handling. Takes only a chain operand.
CLEANUPRET,
// SjLj exception handling setjmp.
EH_SJLJ_SETJMP,
@ -1009,6 +1015,7 @@ namespace llvm {
SDValue LowerFRAME_TO_ARGS_OFFSET(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerEH_RETURN(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerCATCHRET(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerCLEANUPRET(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerEH_SJLJ_SETJMP(SDValue Op, SelectionDAG &DAG) const;
SDValue lowerEH_SJLJ_LONGJMP(SDValue Op, SelectionDAG &DAG) const;
SDValue LowerINIT_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const;

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@ -159,6 +159,14 @@ def CATCHRET : I<0xC3, RawFrm, (outs), (ins GR32:$addr),
def CATCHRET64 : I<0xC3, RawFrm, (outs), (ins GR64:$addr),
"ret{q}\t# CATCHRET",
[(X86catchret GR64:$addr)], IIC_RET>, Sched<[WriteJumpLd]>;
def CLEANUPRET : I<0xC3, RawFrm, (outs), (ins),
"ret{l}\t# CLEANUPRET",
[(X86cleanupret)], IIC_RET>, Sched<[WriteJumpLd]>,
Requires<[Not64BitMode]>;
def CLEANUPRET64 : I<0xC3, RawFrm, (outs), (ins),
"ret{q}\t# CLEANUPRET",
[(X86cleanupret)], IIC_RET>, Sched<[WriteJumpLd]>,
Requires<[In64BitMode]>;
}
let hasSideEffects = 1, isBarrier = 1, isCodeGenOnly = 1,

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@ -207,6 +207,8 @@ def X86ehret : SDNode<"X86ISD::EH_RETURN", SDT_X86EHRET,
def X86catchret : SDNode<"X86ISD::CATCHRET", SDT_X86EHRET, [SDNPHasChain]>;
def X86cleanupret : SDNode<"X86ISD::CLEANUPRET", SDTX86Void, [SDNPHasChain]>;
def X86eh_sjlj_setjmp : SDNode<"X86ISD::EH_SJLJ_SETJMP",
SDTypeProfile<1, 1, [SDTCisInt<0>,
SDTCisPtrTy<1>]>,

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@ -63,7 +63,7 @@ catchendblock: ; preds = %catch,
; X86: movl $0, -{{[0-9]+}}(%ebp)
; X86: movl $1, (%esp)
; X86: calll _f
; X86: [[contbb:LBB0_[0-9]+]]:
; X86: [[contbb:Ltmp[0-9]+]]: # Block address taken
; X86: movl -{{[0-9]+}}(%ebp), %esp
; X86: addl ${{[0-9]+}}, %esp
; X86: popl %esi
@ -111,7 +111,7 @@ catchendblock: ; preds = %catch,
; X64: callq useints
; X64: movl $1, %ecx
; X64: callq f
; X64: [[contbb:\.LBB0_[0-9]+]]:
; X64: [[contbb:.Ltmp[0-9]+]]: # Block address taken
; X64: addq $40, %rsp
; X64: popq %rbp
; X64: retq

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@ -71,7 +71,7 @@ catchendblock: ; preds = %catch, %catch.2, %c
; X86-DAG: movl %[[addr_reg]], 4(%esp)
; X86-DAG: movl $1, (%esp)
; X86: calll _f
; X86: [[contbb:LBB0_[0-9]+]]:
; X86: [[contbb:Ltmp[0-9]+]]: # Block address taken
; X86: movl -{{[0-9]+}}(%ebp), %esp
; X86: retl
@ -120,7 +120,7 @@ catchendblock: ; preds = %catch, %catch.2, %c
; X64-DAG: leaq -[[local_offs:[0-9]+]](%rbp), %rdx
; X64-DAG: movl $1, %ecx
; X64: callq f
; X64: [[contbb:\.LBB0_[0-9]+]]:
; X64: [[contbb:.Ltmp[0-9]+]]: # Block address taken
; X64: addq $48, %rsp
; X64: popq %rbp
; X64: retq