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[WinEH] Emit EH tables for __CxxFrameHandler3 on 32-bit x86 

Small (really small!) C++ exception handling examples work on 32-bit x86
now.

This change disables the use of .seh_* directives in WinException when
CFI is not in use. It also uses absolute symbol references in the tables
instead of imagerel32 relocations.

Also fixes a cache invalidation bug in MMI personality classification.

llvm-svn: 238575
This commit is contained in:
Reid Kleckner 2015-05-29 17:00:57 +00:00
parent 995dde2799
commit 1d3d4adbb9
8 changed files with 268 additions and 196 deletions
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1
llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
View File

@ -268,6 +268,7 @@ bool AsmPrinter::doInitialization(Module &M) {
default: llvm_unreachable("unsupported unwinding information encoding");
case WinEH::EncodingType::Invalid:
break;
case WinEH::EncodingType::X86:
case WinEH::EncodingType::Itanium:
ES = new WinException(this);
break;

415
llvm/lib/CodeGen/AsmPrinter/WinException.cpp
View File

@ -29,6 +29,7 @@
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCWin64EH.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FormattedStream.h"
@ -38,9 +39,11 @@
#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
WinException::WinException(AsmPrinter *A)
: EHStreamer(A), shouldEmitPersonality(false), shouldEmitLSDA(false),
shouldEmitMoves(false) {}
WinException::WinException(AsmPrinter *A) : EHStreamer(A) {
// MSVC's EH tables are always composed of 32-bit words. All known 64-bit
// platforms use an imagerel32 relocation to refer to symbols.
useImageRel32 = (A->getDataLayout().getPointerSizeInBits() == 64);
}
WinException::~WinException() {}
@ -55,11 +58,14 @@ void WinException::beginFunction(const MachineFunction *MF) {
// If any landing pads survive, we need an EH table.
bool hasLandingPads = !MMI->getLandingPads().empty();
const Function *F = MF->getFunction();
const Function *ParentF = MMI->getWinEHParent(F);
shouldEmitMoves = Asm->needsSEHMoves();
const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
unsigned PerEncoding = TLOF.getPersonalityEncoding();
const Function *Per = MF->getMMI().getPersonality();
const Function *Per = MMI->getPersonality();
shouldEmitPersonality = hasLandingPads &&
PerEncoding != dwarf::DW_EH_PE_omit && Per;
@ -68,12 +74,17 @@ void WinException::beginFunction(const MachineFunction *MF) {
shouldEmitLSDA = shouldEmitPersonality &&
LSDAEncoding != dwarf::DW_EH_PE_omit;
// If we're not using CFI, we don't want the CFI or the personality. Emit the
// LSDA if this is the parent function.
if (!Asm->MAI->usesWindowsCFI()) {
shouldEmitLSDA = (hasLandingPads && F == ParentF);
shouldEmitPersonality = false;
return;
}
// If this was an outlined handler, we need to define the label corresponding
// to the offset of the parent frame relative to the stack pointer after the
// prologue.
const Function *F = MF->getFunction();
const Function *ParentF = MMI->getWinEHParent(F);
if (F != ParentF) {
WinEHFuncInfo &FuncInfo = MMI->getWinEHFuncInfo(ParentF);
auto I = FuncInfo.CatchHandlerParentFrameObjOffset.find(F);
@ -89,23 +100,20 @@ void WinException::beginFunction(const MachineFunction *MF) {
}
}
if (!shouldEmitPersonality && !shouldEmitMoves)
return;
if (shouldEmitMoves || shouldEmitPersonality)
Asm->OutStreamer->EmitWinCFIStartProc(Asm->CurrentFnSym);
Asm->OutStreamer->EmitWinCFIStartProc(Asm->CurrentFnSym);
if (!shouldEmitPersonality)
return;
const MCSymbol *PersHandlerSym =
TLOF.getCFIPersonalitySymbol(Per, *Asm->Mang, Asm->TM, MMI);
Asm->OutStreamer->EmitWinEHHandler(PersHandlerSym, true, true);
if (shouldEmitPersonality) {
const MCSymbol *PersHandlerSym =
TLOF.getCFIPersonalitySymbol(Per, *Asm->Mang, Asm->TM, MMI);
Asm->OutStreamer->EmitWinEHHandler(PersHandlerSym, true, true);
}
}
/// endFunction - Gather and emit post-function exception information.
///
void WinException::endFunction(const MachineFunction *MF) {
if (!shouldEmitPersonality && !shouldEmitMoves)
if (!shouldEmitPersonality && !shouldEmitMoves && !shouldEmitLSDA)
return;
EHPersonality Per = MMI->getPersonalityType();
@ -116,16 +124,27 @@ void WinException::endFunction(const MachineFunction *MF) {
if (!isMSVCEHPersonality(Per))
MMI->TidyLandingPads();
if (shouldEmitPersonality) {
if (shouldEmitPersonality || shouldEmitLSDA) {
Asm->OutStreamer->PushSection();
// Emit an UNWIND_INFO struct describing the prologue.
Asm->OutStreamer->EmitWinEHHandlerData();
if (shouldEmitMoves || shouldEmitPersonality) {
// Emit an UNWIND_INFO struct describing the prologue.
Asm->OutStreamer->EmitWinEHHandlerData();
} else {
// Just switch sections to the right xdata section. This use of
// CurrentFnSym assumes that we only emit the LSDA when ending the parent
// function.
MCSection *XData = WinEH::UnwindEmitter::getXDataSection(
Asm->CurrentFnSym, Asm->OutContext);
Asm->OutStreamer->SwitchSection(XData);
}
// Emit the tables appropriate to the personality function in use. If we
// don't recognize the personality, assume it uses an Itanium-style LSDA.
if (Per == EHPersonality::MSVC_Win64SEH)
emitCSpecificHandlerTable();
else if (Per == EHPersonality::MSVC_X86SEH)
emitCSpecificHandlerTable(); // FIXME
else if (Per == EHPersonality::MSVC_CXX)
emitCXXFrameHandler3Table(MF);
else
@ -133,20 +152,24 @@ void WinException::endFunction(const MachineFunction *MF) {
Asm->OutStreamer->PopSection();
}
Asm->OutStreamer->EmitWinCFIEndProc();
if (shouldEmitMoves)
Asm->OutStreamer->EmitWinCFIEndProc();
}
const MCExpr *WinException::createImageRel32(const MCSymbol *Value) {
const MCExpr *WinException::create32bitRef(const MCSymbol *Value) {
if (!Value)
return MCConstantExpr::Create(0, Asm->OutContext);
return MCSymbolRefExpr::Create(Value, MCSymbolRefExpr::VK_COFF_IMGREL32,
return MCSymbolRefExpr::Create(Value, useImageRel32
? MCSymbolRefExpr::VK_COFF_IMGREL32
: MCSymbolRefExpr::VK_None,
Asm->OutContext);
}
const MCExpr *WinException::createImageRel32(const GlobalValue *GV) {
const MCExpr *WinException::create32bitRef(const GlobalValue *GV) {
if (!GV)
return MCConstantExpr::Create(0, Asm->OutContext);
return createImageRel32(Asm->getSymbol(GV));
return create32bitRef(Asm->getSymbol(GV));
}
/// Emit the language-specific data that __C_specific_handler expects. This
@ -227,16 +250,16 @@ void WinException::emitCSpecificHandlerTable() {
// Compute the label range. We may reuse the function begin and end labels
// rather than forming new ones.
const MCExpr *Begin =
createImageRel32(CSE.BeginLabel ? CSE.BeginLabel : EHFuncBeginSym);
create32bitRef(CSE.BeginLabel ? CSE.BeginLabel : EHFuncBeginSym);
const MCExpr *End;
if (CSE.EndLabel) {
// The interval is half-open, so we have to add one to include the return
// address of the last invoke in the range.
End = MCBinaryExpr::CreateAdd(createImageRel32(CSE.EndLabel),
End = MCBinaryExpr::CreateAdd(create32bitRef(CSE.EndLabel),
MCConstantExpr::Create(1, Asm->OutContext),
Asm->OutContext);
} else {
End = createImageRel32(EHFuncEndSym);
End = create32bitRef(EHFuncEndSym);
}
// Emit an entry for each action.
@ -248,7 +271,7 @@ void WinException::emitCSpecificHandlerTable() {
// emit '1' to indicate a catch-all.
const Function *F = Handler.FilterOrFinally;
if (F)
Asm->OutStreamer->EmitValue(createImageRel32(Asm->getSymbol(F)), 4);
Asm->OutStreamer->EmitValue(create32bitRef(Asm->getSymbol(F)), 4);
else
Asm->OutStreamer->EmitIntValue(1, 4);
@ -257,7 +280,7 @@ void WinException::emitCSpecificHandlerTable() {
const BlockAddress *BA = Handler.RecoverBA;
if (BA)
Asm->OutStreamer->EmitValue(
createImageRel32(Asm->GetBlockAddressSymbol(BA)), 4);
create32bitRef(Asm->GetBlockAddressSymbol(BA)), 4);
else
Asm->OutStreamer->EmitIntValue(0, 4);
}
@ -273,9 +296,178 @@ void WinException::emitCXXFrameHandler3Table(const MachineFunction *MF) {
StringRef ParentLinkageName =
GlobalValue::getRealLinkageName(ParentF->getName());
MCSymbol *FuncInfoXData =
Asm->OutContext.getOrCreateSymbol(Twine("$cppxdata$", ParentLinkageName));
OS.EmitValue(createImageRel32(FuncInfoXData), 4);
MCSymbol *FuncInfoXData = nullptr;
if (shouldEmitPersonality) {
FuncInfoXData = Asm->OutContext.getOrCreateSymbol(
Twine("$cppxdata$", ParentLinkageName));
OS.EmitValue(create32bitRef(FuncInfoXData), 4);
extendIP2StateTable(MF, ParentF, FuncInfo);
// Defer emission until we've visited the parent function and all the catch
// handlers. Cleanups don't contribute to the ip2state table, so don't count
// them.
if (ParentF != F && !FuncInfo.CatchHandlerMaxState.count(F))
return;
++FuncInfo.NumIPToStateFuncsVisited;
if (FuncInfo.NumIPToStateFuncsVisited != FuncInfo.CatchHandlerMaxState.size())
return;
} else {
FuncInfoXData = Asm->OutContext.getOrCreateLSDASymbol(ParentLinkageName);
}
MCSymbol *UnwindMapXData = nullptr;
MCSymbol *TryBlockMapXData = nullptr;
MCSymbol *IPToStateXData = nullptr;
if (!FuncInfo.UnwindMap.empty())
UnwindMapXData = Asm->OutContext.getOrCreateSymbol(
Twine("$stateUnwindMap$", ParentLinkageName));
if (!FuncInfo.TryBlockMap.empty())
TryBlockMapXData = Asm->OutContext.getOrCreateSymbol(
Twine("$tryMap$", ParentLinkageName));
if (!FuncInfo.IPToStateList.empty())
IPToStateXData = Asm->OutContext.getOrCreateSymbol(
Twine("$ip2state$", ParentLinkageName));
// FuncInfo {
// uint32_t MagicNumber
// int32_t MaxState;
// UnwindMapEntry *UnwindMap;
// uint32_t NumTryBlocks;
// TryBlockMapEntry *TryBlockMap;
// uint32_t IPMapEntries; // always 0 for x86
// IPToStateMapEntry *IPToStateMap; // always 0 for x86
// uint32_t UnwindHelp; // non-x86 only
// ESTypeList *ESTypeList;
// int32_t EHFlags;
// }
// EHFlags & 1 -> Synchronous exceptions only, no async exceptions.
// EHFlags & 2 -> ???
// EHFlags & 4 -> The function is noexcept(true), unwinding can't continue.
OS.EmitLabel(FuncInfoXData);
OS.EmitIntValue(0x19930522, 4); // MagicNumber
OS.EmitIntValue(FuncInfo.UnwindMap.size(), 4); // MaxState
OS.EmitValue(create32bitRef(UnwindMapXData), 4); // UnwindMap
OS.EmitIntValue(FuncInfo.TryBlockMap.size(), 4); // NumTryBlocks
OS.EmitValue(create32bitRef(TryBlockMapXData), 4); // TryBlockMap
OS.EmitIntValue(FuncInfo.IPToStateList.size(), 4); // IPMapEntries
OS.EmitValue(create32bitRef(IPToStateXData), 4); // IPToStateMap
if (Asm->MAI->usesWindowsCFI())
OS.EmitIntValue(FuncInfo.UnwindHelpFrameOffset, 4); // UnwindHelp
OS.EmitIntValue(0, 4); // ESTypeList
OS.EmitIntValue(1, 4); // EHFlags
// UnwindMapEntry {
// int32_t ToState;
// void (*Action)();
// };
if (UnwindMapXData) {
OS.EmitLabel(UnwindMapXData);
for (const WinEHUnwindMapEntry &UME : FuncInfo.UnwindMap) {
OS.EmitIntValue(UME.ToState, 4); // ToState
OS.EmitValue(create32bitRef(UME.Cleanup), 4); // Action
}
}
// TryBlockMap {
// int32_t TryLow;
// int32_t TryHigh;
// int32_t CatchHigh;
// int32_t NumCatches;
// HandlerType *HandlerArray;
// };
if (TryBlockMapXData) {
OS.EmitLabel(TryBlockMapXData);
SmallVector<MCSymbol *, 1> HandlerMaps;
for (size_t I = 0, E = FuncInfo.TryBlockMap.size(); I != E; ++I) {
WinEHTryBlockMapEntry &TBME = FuncInfo.TryBlockMap[I];
MCSymbol *HandlerMapXData = nullptr;
if (!TBME.HandlerArray.empty())
HandlerMapXData =
Asm->OutContext.getOrCreateSymbol(Twine("$handlerMap$")
.concat(Twine(I))
.concat("$")
.concat(ParentLinkageName));
HandlerMaps.push_back(HandlerMapXData);
int CatchHigh = -1;
for (WinEHHandlerType &HT : TBME.HandlerArray)
CatchHigh =
std::max(CatchHigh, FuncInfo.CatchHandlerMaxState[HT.Handler]);
assert(TBME.TryLow <= TBME.TryHigh);
OS.EmitIntValue(TBME.TryLow, 4); // TryLow
OS.EmitIntValue(TBME.TryHigh, 4); // TryHigh
OS.EmitIntValue(CatchHigh, 4); // CatchHigh
OS.EmitIntValue(TBME.HandlerArray.size(), 4); // NumCatches
OS.EmitValue(create32bitRef(HandlerMapXData), 4); // HandlerArray
}
for (size_t I = 0, E = FuncInfo.TryBlockMap.size(); I != E; ++I) {
WinEHTryBlockMapEntry &TBME = FuncInfo.TryBlockMap[I];
MCSymbol *HandlerMapXData = HandlerMaps[I];
if (!HandlerMapXData)
continue;
// HandlerType {
// int32_t Adjectives;
// TypeDescriptor *Type;
// int32_t CatchObjOffset;
// void (*Handler)();
// int32_t ParentFrameOffset; // x64 only
// };
OS.EmitLabel(HandlerMapXData);
for (const WinEHHandlerType &HT : TBME.HandlerArray) {
// Get the frame escape label with the offset of the catch object. If
// the index is -1, then there is no catch object, and we should emit an
// offset of zero, indicating that no copy will occur.
const MCExpr *FrameAllocOffsetRef = nullptr;
if (HT.CatchObjRecoverIdx >= 0) {
MCSymbol *FrameAllocOffset =
Asm->OutContext.getOrCreateFrameAllocSymbol(
GlobalValue::getRealLinkageName(ParentF->getName()),
HT.CatchObjRecoverIdx);
FrameAllocOffsetRef = MCSymbolRefExpr::Create(
FrameAllocOffset, MCSymbolRefExpr::VK_None, Asm->OutContext);
} else {
FrameAllocOffsetRef = MCConstantExpr::Create(0, Asm->OutContext);
}
OS.EmitIntValue(HT.Adjectives, 4); // Adjectives
OS.EmitValue(create32bitRef(HT.TypeDescriptor), 4); // Type
OS.EmitValue(FrameAllocOffsetRef, 4); // CatchObjOffset
OS.EmitValue(create32bitRef(HT.Handler), 4); // Handler
if (shouldEmitPersonality) {
MCSymbol *ParentFrameOffset =
Asm->OutContext.getOrCreateParentFrameOffsetSymbol(
GlobalValue::getRealLinkageName(HT.Handler->getName()));
const MCSymbolRefExpr *ParentFrameOffsetRef = MCSymbolRefExpr::Create(
ParentFrameOffset, MCSymbolRefExpr::VK_None, Asm->OutContext);
OS.EmitValue(ParentFrameOffsetRef, 4); // ParentFrameOffset
}
}
}
}
// IPToStateMapEntry {
// void *IP;
// int32_t State;
// };
if (IPToStateXData) {
OS.EmitLabel(IPToStateXData);
for (auto &IPStatePair : FuncInfo.IPToStateList) {
OS.EmitValue(create32bitRef(IPStatePair.first), 4); // IP
OS.EmitIntValue(IPStatePair.second, 4); // State
}
}
}
void WinException::extendIP2StateTable(const MachineFunction *MF,
const Function *ParentF,
WinEHFuncInfo &FuncInfo) {
const Function *F = MF->getFunction();
// The Itanium LSDA table sorts similar landing pads together to simplify the
// actions table, but we don't need that.
@ -306,8 +498,8 @@ void WinException::emitCXXFrameHandler3Table(const MachineFunction *MF) {
FuncInfo.IPToStateList.push_back(std::make_pair(LastLabel, -1));
LastEHState = -1;
} else if (FuncInfo.HandlerBaseState.count(F)) {
FuncInfo.IPToStateList.push_back(std::make_pair(LastLabel,
FuncInfo.HandlerBaseState[F]));
FuncInfo.IPToStateList.push_back(
std::make_pair(LastLabel, FuncInfo.HandlerBaseState[F]));
LastEHState = FuncInfo.HandlerBaseState[F];
}
for (const auto &MBB : *MF) {
@ -348,157 +540,4 @@ void WinException::emitCXXFrameHandler3Table(const MachineFunction *MF) {
LastLabel = LandingPad->EndLabels[P.RangeIndex];
}
}
// Defer emission until we've visited the parent function and all the catch
// handlers. Cleanups don't contribute to the ip2state table yet, so don't
// count them.
if (ParentF != F && !FuncInfo.CatchHandlerMaxState.count(F))
return;
++FuncInfo.NumIPToStateFuncsVisited;
if (FuncInfo.NumIPToStateFuncsVisited != FuncInfo.CatchHandlerMaxState.size())
return;
MCSymbol *UnwindMapXData = nullptr;
MCSymbol *TryBlockMapXData = nullptr;
MCSymbol *IPToStateXData = nullptr;
if (!FuncInfo.UnwindMap.empty())
UnwindMapXData = Asm->OutContext.getOrCreateSymbol(
Twine("$stateUnwindMap$", ParentLinkageName));
if (!FuncInfo.TryBlockMap.empty())
TryBlockMapXData = Asm->OutContext.getOrCreateSymbol(
Twine("$tryMap$", ParentLinkageName));
if (!FuncInfo.IPToStateList.empty())
IPToStateXData = Asm->OutContext.getOrCreateSymbol(
Twine("$ip2state$", ParentLinkageName));
// FuncInfo {
// uint32_t MagicNumber
// int32_t MaxState;
// UnwindMapEntry *UnwindMap;
// uint32_t NumTryBlocks;
// TryBlockMapEntry *TryBlockMap;
// uint32_t IPMapEntries;
// IPToStateMapEntry *IPToStateMap;
// uint32_t UnwindHelp; // (x64/ARM only)
// ESTypeList *ESTypeList;
// int32_t EHFlags;
// }
// EHFlags & 1 -> Synchronous exceptions only, no async exceptions.
// EHFlags & 2 -> ???
// EHFlags & 4 -> The function is noexcept(true), unwinding can't continue.
OS.EmitLabel(FuncInfoXData);
OS.EmitIntValue(0x19930522, 4); // MagicNumber
OS.EmitIntValue(FuncInfo.UnwindMap.size(), 4); // MaxState
OS.EmitValue(createImageRel32(UnwindMapXData), 4); // UnwindMap
OS.EmitIntValue(FuncInfo.TryBlockMap.size(), 4); // NumTryBlocks
OS.EmitValue(createImageRel32(TryBlockMapXData), 4); // TryBlockMap
OS.EmitIntValue(FuncInfo.IPToStateList.size(), 4); // IPMapEntries
OS.EmitValue(createImageRel32(IPToStateXData), 4); // IPToStateMap
OS.EmitIntValue(FuncInfo.UnwindHelpFrameOffset, 4); // UnwindHelp
OS.EmitIntValue(0, 4); // ESTypeList
OS.EmitIntValue(1, 4); // EHFlags
// UnwindMapEntry {
// int32_t ToState;
// void (*Action)();
// };
if (UnwindMapXData) {
OS.EmitLabel(UnwindMapXData);
for (const WinEHUnwindMapEntry &UME : FuncInfo.UnwindMap) {
OS.EmitIntValue(UME.ToState, 4); // ToState
OS.EmitValue(createImageRel32(UME.Cleanup), 4); // Action
}
}
// TryBlockMap {
// int32_t TryLow;
// int32_t TryHigh;
// int32_t CatchHigh;
// int32_t NumCatches;
// HandlerType *HandlerArray;
// };
if (TryBlockMapXData) {
OS.EmitLabel(TryBlockMapXData);
SmallVector<MCSymbol *, 1> HandlerMaps;
for (size_t I = 0, E = FuncInfo.TryBlockMap.size(); I != E; ++I) {
WinEHTryBlockMapEntry &TBME = FuncInfo.TryBlockMap[I];
MCSymbol *HandlerMapXData = nullptr;
if (!TBME.HandlerArray.empty())
HandlerMapXData =
Asm->OutContext.getOrCreateSymbol(Twine("$handlerMap$")
.concat(Twine(I))
.concat("$")
.concat(ParentLinkageName));
HandlerMaps.push_back(HandlerMapXData);
int CatchHigh = -1;
for (WinEHHandlerType &HT : TBME.HandlerArray)
CatchHigh =
std::max(CatchHigh, FuncInfo.CatchHandlerMaxState[HT.Handler]);
assert(TBME.TryLow <= TBME.TryHigh);
OS.EmitIntValue(TBME.TryLow, 4); // TryLow
OS.EmitIntValue(TBME.TryHigh, 4); // TryHigh
OS.EmitIntValue(CatchHigh, 4); // CatchHigh
OS.EmitIntValue(TBME.HandlerArray.size(), 4); // NumCatches
OS.EmitValue(createImageRel32(HandlerMapXData), 4); // HandlerArray
}
for (size_t I = 0, E = FuncInfo.TryBlockMap.size(); I != E; ++I) {
WinEHTryBlockMapEntry &TBME = FuncInfo.TryBlockMap[I];
MCSymbol *HandlerMapXData = HandlerMaps[I];
if (!HandlerMapXData)
continue;
// HandlerType {
// int32_t Adjectives;
// TypeDescriptor *Type;
// int32_t CatchObjOffset;
// void (*Handler)();
// int32_t ParentFrameOffset; // x64 only
// };
OS.EmitLabel(HandlerMapXData);
for (const WinEHHandlerType &HT : TBME.HandlerArray) {
MCSymbol *ParentFrameOffset =
Asm->OutContext.getOrCreateParentFrameOffsetSymbol(
GlobalValue::getRealLinkageName(HT.Handler->getName()));
const MCSymbolRefExpr *ParentFrameOffsetRef = MCSymbolRefExpr::Create(
ParentFrameOffset, MCSymbolRefExpr::VK_None, Asm->OutContext);
// Get the frame escape label with the offset of the catch object. If
// the index is -1, then there is no catch object, and we should emit an
// offset of zero, indicating that no copy will occur.
const MCExpr *FrameAllocOffsetRef = nullptr;
if (HT.CatchObjRecoverIdx >= 0) {
MCSymbol *FrameAllocOffset =
Asm->OutContext.getOrCreateFrameAllocSymbol(
GlobalValue::getRealLinkageName(ParentF->getName()),
HT.CatchObjRecoverIdx);
FrameAllocOffsetRef = MCSymbolRefExpr::Create(
FrameAllocOffset, MCSymbolRefExpr::VK_None, Asm->OutContext);
} else {
FrameAllocOffsetRef = MCConstantExpr::Create(0, Asm->OutContext);
}
OS.EmitIntValue(HT.Adjectives, 4); // Adjectives
OS.EmitValue(createImageRel32(HT.TypeDescriptor), 4); // Type
OS.EmitValue(FrameAllocOffsetRef, 4); // CatchObjOffset
OS.EmitValue(createImageRel32(HT.Handler), 4); // Handler
OS.EmitValue(ParentFrameOffsetRef, 4); // ParentFrameOffset
}
}
}
// IPToStateMapEntry {
// void *IP;
// int32_t State;
// };
if (IPToStateXData) {
OS.EmitLabel(IPToStateXData);
for (auto &IPStatePair : FuncInfo.IPToStateList) {
OS.EmitValue(createImageRel32(IPStatePair.first), 4); // IP
OS.EmitIntValue(IPStatePair.second, 4); // State
}
}
}

18
llvm/lib/CodeGen/AsmPrinter/WinException.h
View File

@ -17,26 +17,34 @@
#include "EHStreamer.h"
namespace llvm {
class Function;
class GlobalValue;
class MachineFunction;
class MCExpr;
struct WinEHFuncInfo;
class WinException : public EHStreamer {
/// Per-function flag to indicate if personality info should be emitted.
bool shouldEmitPersonality;
bool shouldEmitPersonality = false;
/// Per-function flag to indicate if the LSDA should be emitted.
bool shouldEmitLSDA;
bool shouldEmitLSDA = false;
/// Per-function flag to indicate if frame moves info should be emitted.
bool shouldEmitMoves;
bool shouldEmitMoves = false;
/// True if this is a 64-bit target and we should use image relative offsets.
bool useImageRel32 = false;
void emitCSpecificHandlerTable();
void emitCXXFrameHandler3Table(const MachineFunction *MF);
const MCExpr *createImageRel32(const MCSymbol *Value);
const MCExpr *createImageRel32(const GlobalValue *GV);
void extendIP2StateTable(const MachineFunction *MF, const Function *ParentF,
WinEHFuncInfo &FuncInfo);
const MCExpr *create32bitRef(const MCSymbol *Value);
const MCExpr *create32bitRef(const GlobalValue *GV);
public:
//===--------------------------------------------------------------------===//

1
llvm/lib/CodeGen/MachineModuleInfo.cpp
View File

@ -308,6 +308,7 @@ void MachineModuleInfo::EndFunction() {
// Clean up exception info.
LandingPads.clear();
PersonalityTypeCache = EHPersonality::Unknown;
CallSiteMap.clear();
TypeInfos.clear();
FilterIds.clear();

6
llvm/lib/MC/MCAsmStreamer.cpp
View File

@ -1102,9 +1102,9 @@ void MCAsmStreamer::EmitWinEHHandlerData() {
// We only do this so the section switch that terminates the handler
// data block is visible.
WinEH::FrameInfo *CurFrame = getCurrentWinFrameInfo();
if (MCSection *XData = WinEH::UnwindEmitter::getXDataSection(
CurFrame->Function, getContext()))
SwitchSectionNoChange(XData);
MCSection *XData =
WinEH::UnwindEmitter::getXDataSection(CurFrame->Function, getContext());
SwitchSectionNoChange(XData);
OS << "\t.seh_handlerdata";
EmitEOL();

6
llvm/lib/MC/MCStreamer.cpp
View File

@ -391,11 +391,17 @@ void MCStreamer::EmitCFIWindowSave() {
}
void MCStreamer::EnsureValidWinFrameInfo() {
const MCAsmInfo *MAI = Context.getAsmInfo();
if (!MAI->usesWindowsCFI())
report_fatal_error(".seh_* directives are not supported on this target");
if (!CurrentWinFrameInfo || CurrentWinFrameInfo->End)
report_fatal_error("No open Win64 EH frame function!");
}
void MCStreamer::EmitWinCFIStartProc(const MCSymbol *Symbol) {
const MCAsmInfo *MAI = Context.getAsmInfo();
if (!MAI->usesWindowsCFI())
report_fatal_error(".seh_* directives are not supported on this target");
if (CurrentWinFrameInfo && !CurrentWinFrameInfo->End)
report_fatal_error("Starting a function before ending the previous one!");

5
llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
View File

@ -132,6 +132,11 @@ X86MCAsmInfoMicrosoft::X86MCAsmInfoMicrosoft(const Triple &Triple) {
PrivateLabelPrefix = ".L";
PointerSize = 8;
WinEHEncodingType = WinEH::EncodingType::Itanium;
} else {
// 32-bit X86 doesn't use CFI, so this isn't a real encoding type. It's just
// a place holder that the Windows EHStreamer looks for to suppress CFI
// output. In particular, usesWindowsCFI() returns false.
WinEHEncodingType = WinEH::EncodingType::X86;
}
ExceptionsType = ExceptionHandling::WinEH;

12
llvm/test/CodeGen/X86/win32-eh.ll
View File

@ -87,6 +87,18 @@ catchall:
; CHECK: movl %[[next]], %fs:0
; CHECK: retl
; CHECK: .section .xdata,"dr"
; CHECK-LABEL: L__ehtable$use_CxxFrameHandler3:
; CHECK-NEXT: .long 429065506
; CHECK-NEXT: .long 2
; CHECK-NEXT: .long ($stateUnwindMap$use_CxxFrameHandler3)
; CHECK-NEXT: .long 1
; CHECK-NEXT: .long ($tryMap$use_CxxFrameHandler3)
; CHECK-NEXT: .long 0
; CHECK-NEXT: .long 0
; CHECK-NEXT: .long 0
; CHECK-NEXT: .long 1
; CHECK-LABEL: ___ehhandler$use_CxxFrameHandler3:
; CHECK: movl $L__ehtable$use_CxxFrameHandler3, %eax
; CHECK: jmp ___CxxFrameHandler3 # TAILCALL