//===----------------------------------------------------------------------===//
#include "llvm/MC/MCWin64EH.h"
-#include "llvm/MC/MCStreamer.h"
+#include "llvm/ADT/Twine.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
-#include "llvm/Target/TargetAsmInfo.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCSectionCOFF.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
namespace llvm {
static void EmitUnwindCode(MCStreamer &streamer, MCSymbol *begin,
MCWin64EHInstruction &inst) {
- uint8_t b1, b2;
+ uint8_t b2;
uint16_t w;
- b2 = (inst.getOperation() & 0x0F) << 4;
+ b2 = (inst.getOperation() & 0x0F);
switch (inst.getOperation()) {
case Win64EH::UOP_PushNonVol:
EmitAbsDifference(streamer, inst.getLabel(), begin);
- b2 |= inst.getRegister() & 0x0F;
+ b2 |= (inst.getRegister() & 0x0F) << 4;
streamer.EmitIntValue(b2, 1);
break;
case Win64EH::UOP_AllocLarge:
EmitAbsDifference(streamer, inst.getLabel(), begin);
if (inst.getSize() > 512*1024-8) {
- b2 |= 1;
+ b2 |= 0x10;
streamer.EmitIntValue(b2, 1);
w = inst.getSize() & 0xFFF8;
streamer.EmitIntValue(w, 2);
streamer.EmitIntValue(w, 2);
break;
case Win64EH::UOP_AllocSmall:
- b2 |= ((inst.getSize()-8) >> 3) & 0x0F;
+ b2 |= (((inst.getSize()-8) >> 3) & 0x0F) << 4;
EmitAbsDifference(streamer, inst.getLabel(), begin);
streamer.EmitIntValue(b2, 1);
break;
case Win64EH::UOP_SetFPReg:
- b1 = inst.getOffset() & 0xF0;
- streamer.EmitIntValue(b1, 1);
+ EmitAbsDifference(streamer, inst.getLabel(), begin);
streamer.EmitIntValue(b2, 1);
break;
case Win64EH::UOP_SaveNonVol:
case Win64EH::UOP_SaveXMM128:
- b2 |= inst.getRegister() & 0x0F;
+ b2 |= (inst.getRegister() & 0x0F) << 4;
EmitAbsDifference(streamer, inst.getLabel(), begin);
streamer.EmitIntValue(b2, 1);
w = inst.getOffset() >> 3;
break;
case Win64EH::UOP_SaveNonVolBig:
case Win64EH::UOP_SaveXMM128Big:
- b2 |= inst.getRegister() & 0x0F;
+ b2 |= (inst.getRegister() & 0x0F) << 4;
EmitAbsDifference(streamer, inst.getLabel(), begin);
streamer.EmitIntValue(b2, 1);
if (inst.getOperation() == Win64EH::UOP_SaveXMM128Big)
break;
case Win64EH::UOP_PushMachFrame:
if (inst.isPushCodeFrame())
- b2 |= 1;
+ b2 |= 0x10;
EmitAbsDifference(streamer, inst.getLabel(), begin);
streamer.EmitIntValue(b2, 1);
break;
}
}
+static void EmitSymbolRefWithOfs(MCStreamer &streamer,
+ const MCSymbol *Base,
+ const MCSymbol *Other) {
+ MCContext &Context = streamer.getContext();
+ const MCSymbolRefExpr *BaseRef = MCSymbolRefExpr::Create(Base, Context);
+ const MCSymbolRefExpr *OtherRef = MCSymbolRefExpr::Create(Other, Context);
+ const MCExpr *Ofs = MCBinaryExpr::CreateSub(OtherRef, BaseRef, Context);
+ const MCSymbolRefExpr *BaseRefRel = MCSymbolRefExpr::Create(Base,
+ MCSymbolRefExpr::VK_COFF_IMGREL32,
+ Context);
+ streamer.EmitValue(MCBinaryExpr::CreateAdd(BaseRefRel, Ofs, Context), 4);
+}
+
static void EmitRuntimeFunction(MCStreamer &streamer,
const MCWin64EHUnwindInfo *info) {
MCContext &context = streamer.getContext();
streamer.EmitValueToAlignment(4);
- streamer.EmitValue(MCSymbolRefExpr::Create(info->Begin, context), 4);
- streamer.EmitValue(MCSymbolRefExpr::Create(info->End, context), 4);
- streamer.EmitValue(MCSymbolRefExpr::Create(info->Symbol, context), 4);
+ EmitSymbolRefWithOfs(streamer, info->Function, info->Begin);
+ EmitSymbolRefWithOfs(streamer, info->Function, info->End);
+ streamer.EmitValue(MCSymbolRefExpr::Create(info->Symbol,
+ MCSymbolRefExpr::VK_COFF_IMGREL32,
+ context), 4);
}
static void EmitUnwindInfo(MCStreamer &streamer, MCWin64EHUnwindInfo *info) {
MCContext &context = streamer.getContext();
streamer.EmitValueToAlignment(4);
- // Upper 3 bits are the version number (currently 1).
- uint8_t flags = 0x20;
info->Symbol = context.CreateTempSymbol();
streamer.EmitLabel(info->Symbol);
+ // Upper 3 bits are the version number (currently 1).
+ uint8_t flags = 0x01;
if (info->ChainedParent)
- flags |= Win64EH::UNW_ChainInfo;
+ flags |= Win64EH::UNW_ChainInfo << 3;
else {
if (info->HandlesUnwind)
- flags |= Win64EH::UNW_TerminateHandler;
+ flags |= Win64EH::UNW_TerminateHandler << 3;
if (info->HandlesExceptions)
- flags |= Win64EH::UNW_ExceptionHandler;
+ flags |= Win64EH::UNW_ExceptionHandler << 3;
}
streamer.EmitIntValue(flags, 1);
- EmitAbsDifference(streamer, info->PrologEnd, info->Begin);
+ if (info->PrologEnd)
+ EmitAbsDifference(streamer, info->PrologEnd, info->Begin);
+ else
+ streamer.EmitIntValue(0, 1);
uint8_t numCodes = CountOfUnwindCodes(info->Instructions);
streamer.EmitIntValue(numCodes, 1);
if (info->LastFrameInst >= 0) {
MCWin64EHInstruction &frameInst = info->Instructions[info->LastFrameInst];
assert(frameInst.getOperation() == Win64EH::UOP_SetFPReg);
- frame = ((frameInst.getRegister() & 0x0F) << 4) |
- ((frameInst.getOffset() >> 4) & 0x0F);
+ frame = (frameInst.getRegister() & 0x0F) |
+ (frameInst.getOffset() & 0xF0);
}
streamer.EmitIntValue(frame, 1);
EmitUnwindCode(streamer, info->Begin, inst);
}
- if (flags & Win64EH::UNW_ChainInfo)
+ // For alignment purposes, the instruction array will always have an even
+ // number of entries, with the final entry potentially unused (in which case
+ // the array will be one longer than indicated by the count of unwind codes
+ // field).
+ if (numCodes & 1) {
+ streamer.EmitIntValue(0, 2);
+ }
+
+ if (flags & (Win64EH::UNW_ChainInfo << 3))
EmitRuntimeFunction(streamer, info->ChainedParent);
- else if (flags &(Win64EH::UNW_TerminateHandler|Win64EH::UNW_ExceptionHandler))
- streamer.EmitValue(MCSymbolRefExpr::Create(info->ExceptionHandler, context),
- 4);
+ else if (flags &
+ ((Win64EH::UNW_TerminateHandler|Win64EH::UNW_ExceptionHandler) << 3))
+ streamer.EmitValue(MCSymbolRefExpr::Create(info->ExceptionHandler,
+ MCSymbolRefExpr::VK_COFF_IMGREL32,
+ context), 4);
+ else if (numCodes == 0) {
+ // The minimum size of an UNWIND_INFO struct is 8 bytes. If we're not
+ // a chained unwind info, if there is no handler, and if there are fewer
+ // than 2 slots used in the unwind code array, we have to pad to 8 bytes.
+ streamer.EmitIntValue(0, 4);
+ }
+}
+
+StringRef MCWin64EHUnwindEmitter::GetSectionSuffix(const MCSymbol *func) {
+ if (!func || !func->isInSection()) return "";
+ const MCSection *section = &func->getSection();
+ const MCSectionCOFF *COFFSection;
+ if ((COFFSection = dyn_cast<MCSectionCOFF>(section))) {
+ StringRef name = COFFSection->getSectionName();
+ size_t dollar = name.find('$');
+ size_t dot = name.find('.', 1);
+ if (dollar == StringRef::npos && dot == StringRef::npos)
+ return "";
+ if (dot == StringRef::npos)
+ return name.substr(dollar);
+ if (dollar == StringRef::npos || dot < dollar)
+ return name.substr(dot);
+ return name.substr(dollar);
+ }
+ return "";
+}
+
+static const MCSection *getWin64EHTableSection(StringRef suffix,
+ MCContext &context) {
+ if (suffix == "")
+ return context.getObjectFileInfo()->getXDataSection();
+
+ return context.getCOFFSection((".xdata"+suffix).str(),
+ COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
+ COFF::IMAGE_SCN_MEM_READ,
+ SectionKind::getDataRel());
+}
+
+static const MCSection *getWin64EHFuncTableSection(StringRef suffix,
+ MCContext &context) {
+ if (suffix == "")
+ return context.getObjectFileInfo()->getPDataSection();
+ return context.getCOFFSection((".pdata"+suffix).str(),
+ COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
+ COFF::IMAGE_SCN_MEM_READ,
+ SectionKind::getDataRel());
}
void MCWin64EHUnwindEmitter::EmitUnwindInfo(MCStreamer &streamer,
// Switch sections (the static function above is meant to be called from
// here and from Emit().
MCContext &context = streamer.getContext();
- const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
- const MCSection *xdataSect = asmInfo.getWin64EHTableSection();
+ const MCSection *xdataSect =
+ getWin64EHTableSection(GetSectionSuffix(info->Function), context);
streamer.SwitchSection(xdataSect);
llvm::EmitUnwindInfo(streamer, info);
void MCWin64EHUnwindEmitter::Emit(MCStreamer &streamer) {
MCContext &context = streamer.getContext();
// Emit the unwind info structs first.
- const TargetAsmInfo &asmInfo = context.getTargetAsmInfo();
- const MCSection *xdataSect = asmInfo.getWin64EHTableSection();
- streamer.SwitchSection(xdataSect);
- for (unsigned i = 0; i < streamer.getNumW64UnwindInfos(); ++i)
- llvm::EmitUnwindInfo(streamer, &streamer.getW64UnwindInfo(i));
+ for (unsigned i = 0; i < streamer.getNumW64UnwindInfos(); ++i) {
+ MCWin64EHUnwindInfo &info = streamer.getW64UnwindInfo(i);
+ const MCSection *xdataSect =
+ getWin64EHTableSection(GetSectionSuffix(info.Function), context);
+ streamer.SwitchSection(xdataSect);
+ llvm::EmitUnwindInfo(streamer, &info);
+ }
// Now emit RUNTIME_FUNCTION entries.
- const MCSection *pdataSect = asmInfo.getWin64EHFuncTableSection();
- streamer.SwitchSection(pdataSect);
- for (unsigned i = 0; i < streamer.getNumW64UnwindInfos(); ++i)
- EmitRuntimeFunction(streamer, &streamer.getW64UnwindInfo(i));
+ for (unsigned i = 0; i < streamer.getNumW64UnwindInfos(); ++i) {
+ MCWin64EHUnwindInfo &info = streamer.getW64UnwindInfo(i);
+ const MCSection *pdataSect =
+ getWin64EHFuncTableSection(GetSectionSuffix(info.Function), context);
+ streamer.SwitchSection(pdataSect);
+ EmitRuntimeFunction(streamer, &info);
+ }
}
} // End of namespace llvm