//===----------------------------------------------------------------------===//
#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"
+#include "llvm/Support/Win64EH.h"
namespace llvm {
// NOTE: All relocations generated here are 4-byte image-relative.
-static uint8_t CountOfUnwindCodes(std::vector<MCWin64EHInstruction> &instArray){
- uint8_t count = 0;
- for (std::vector<MCWin64EHInstruction>::const_iterator I = instArray.begin(),
- E = instArray.end(); I != E; ++I) {
- switch (I->getOperation()) {
+static uint8_t CountOfUnwindCodes(std::vector<WinEH::Instruction> &Insns) {
+ uint8_t Count = 0;
+ for (const auto &I : Insns) {
+ switch (static_cast<Win64EH::UnwindOpcodes>(I.Operation)) {
case Win64EH::UOP_PushNonVol:
case Win64EH::UOP_AllocSmall:
case Win64EH::UOP_SetFPReg:
case Win64EH::UOP_PushMachFrame:
- count += 1;
+ Count += 1;
break;
case Win64EH::UOP_SaveNonVol:
case Win64EH::UOP_SaveXMM128:
- count += 2;
+ Count += 2;
break;
case Win64EH::UOP_SaveNonVolBig:
case Win64EH::UOP_SaveXMM128Big:
- count += 3;
+ Count += 3;
break;
case Win64EH::UOP_AllocLarge:
- if (I->getSize() > 512*1024-8)
- count += 3;
- else
- count += 2;
+ Count += (I.Offset > 512 * 1024 - 8) ? 3 : 2;
break;
}
}
- return count;
+ return Count;
}
-static void EmitUnwindCode(MCStreamer &streamer, MCWin64EHInstruction &inst) {
- uint8_t b1, b2;
+static void EmitAbsDifference(MCStreamer &Streamer, const MCSymbol *LHS,
+ const MCSymbol *RHS) {
+ MCContext &Context = Streamer.getContext();
+ const MCExpr *Diff =
+ MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(LHS, Context),
+ MCSymbolRefExpr::Create(RHS, Context), Context);
+ Streamer.EmitValue(Diff, 1);
+}
+
+static void EmitUnwindCode(MCStreamer &streamer, const MCSymbol *begin,
+ WinEH::Instruction &inst) {
+ uint8_t b2;
uint16_t w;
- b2 = (inst.getOperation() & 0x0F) << 4;
- switch (inst.getOperation()) {
+ b2 = (inst.Operation & 0x0F);
+ switch (static_cast<Win64EH::UnwindOpcodes>(inst.Operation)) {
case Win64EH::UOP_PushNonVol:
- streamer.EmitIntValue(0, 1);
- b2 |= inst.getRegister() & 0x0F;
+ EmitAbsDifference(streamer, inst.Label, begin);
+ b2 |= (inst.Register & 0x0F) << 4;
streamer.EmitIntValue(b2, 1);
break;
case Win64EH::UOP_AllocLarge:
- streamer.EmitIntValue(0, 1);
- if (inst.getSize() > 512*1024-8) {
- b2 |= 1;
+ EmitAbsDifference(streamer, inst.Label, begin);
+ if (inst.Offset > 512 * 1024 - 8) {
+ b2 |= 0x10;
streamer.EmitIntValue(b2, 1);
- w = inst.getSize() & 0xFFF8;
+ w = inst.Offset & 0xFFF8;
streamer.EmitIntValue(w, 2);
- w = inst.getSize() >> 16;
+ w = inst.Offset >> 16;
} else {
streamer.EmitIntValue(b2, 1);
- w = inst.getSize() >> 3;
+ w = inst.Offset >> 3;
}
streamer.EmitIntValue(w, 2);
break;
case Win64EH::UOP_AllocSmall:
- b2 |= (inst.getSize() >> 3) & 0x0F;
- streamer.EmitIntValue(0, 1);
+ b2 |= (((inst.Offset - 8) >> 3) & 0x0F) << 4;
+ EmitAbsDifference(streamer, inst.Label, begin);
streamer.EmitIntValue(b2, 1);
break;
case Win64EH::UOP_SetFPReg:
- b1 = inst.getOffset() & 0xF0;
- streamer.EmitIntValue(b1, 1);
+ EmitAbsDifference(streamer, inst.Label, begin);
streamer.EmitIntValue(b2, 1);
break;
case Win64EH::UOP_SaveNonVol:
case Win64EH::UOP_SaveXMM128:
- b2 |= inst.getRegister() & 0x0F;
- streamer.EmitIntValue(0, 1);
+ b2 |= (inst.Register & 0x0F) << 4;
+ EmitAbsDifference(streamer, inst.Label, begin);
streamer.EmitIntValue(b2, 1);
- w = inst.getOffset() >> 3;
- if (inst.getOperation() == Win64EH::UOP_SaveXMM128)
+ w = inst.Offset >> 3;
+ if (inst.Operation == Win64EH::UOP_SaveXMM128)
w >>= 1;
streamer.EmitIntValue(w, 2);
break;
case Win64EH::UOP_SaveNonVolBig:
case Win64EH::UOP_SaveXMM128Big:
- b2 |= inst.getRegister() & 0x0F;
- streamer.EmitIntValue(0, 1);
+ b2 |= (inst.Register & 0x0F) << 4;
+ EmitAbsDifference(streamer, inst.Label, begin);
streamer.EmitIntValue(b2, 1);
- if (inst.getOperation() == Win64EH::UOP_SaveXMM128Big)
- w = inst.getOffset() & 0xFFF0;
+ if (inst.Operation == Win64EH::UOP_SaveXMM128Big)
+ w = inst.Offset & 0xFFF0;
else
- w = inst.getOffset() & 0xFFF8;
+ w = inst.Offset & 0xFFF8;
streamer.EmitIntValue(w, 2);
- w = inst.getOffset() >> 16;
+ w = inst.Offset >> 16;
streamer.EmitIntValue(w, 2);
break;
case Win64EH::UOP_PushMachFrame:
- if (inst.isPushCodeFrame())
- b2 |= 1;
- streamer.EmitIntValue(0, 1);
+ if (inst.Offset == 1)
+ b2 |= 0x10;
+ EmitAbsDifference(streamer, inst.Label, 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) {
+ const WinEH::FrameInfo *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) {
+static void EmitUnwindInfo(MCStreamer &streamer, WinEH::FrameInfo *info) {
// If this UNWIND_INFO already has a symbol, it's already been emitted.
- if (info->Symbol) return;
+ if (info->Symbol)
+ return;
MCContext &context = streamer.getContext();
+ MCSymbol *Label = context.CreateTempSymbol();
+
streamer.EmitValueToAlignment(4);
- // Upper 3 bits are the version number (currently 1).
- uint8_t flags = 0x20;
- info->Symbol = context.CreateTempSymbol();
- streamer.EmitLabel(info->Symbol);
+ streamer.EmitLabel(Label);
+ info->Symbol = Label;
+ // 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);
- // Build up the prolog size expression.
- const MCExpr *prologSize = MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(
- info->PrologEnd, context),
- MCSymbolRefExpr::Create(
- info->Begin, context),
- context);
- streamer.EmitAbsValue(prologSize, 1);
+ if (info->PrologEnd)
+ EmitAbsDifference(streamer, info->PrologEnd, info->Begin);
+ else
+ streamer.EmitIntValue(0, 1);
uint8_t numCodes = CountOfUnwindCodes(info->Instructions);
streamer.EmitIntValue(numCodes, 1);
uint8_t frame = 0;
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);
+ WinEH::Instruction &frameInst = info->Instructions[info->LastFrameInst];
+ assert(frameInst.Operation == Win64EH::UOP_SetFPReg);
+ frame = (frameInst.Register & 0x0F) | (frameInst.Offset & 0xF0);
}
streamer.EmitIntValue(frame, 1);
// Emit unwind instructions (in reverse order).
uint8_t numInst = info->Instructions.size();
for (uint8_t c = 0; c < numInst; ++c) {
- MCWin64EHInstruction inst = info->Instructions.back();
+ WinEH::Instruction inst = info->Instructions.back();
info->Instructions.pop_back();
- EmitUnwindCode(streamer, inst);
+ 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);
+ }
}
-void MCWin64EHUnwindEmitter::EmitUnwindInfo(MCStreamer &streamer,
- MCWin64EHUnwindInfo *info) {
- // 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();
- streamer.SwitchSection(xdataSect);
-
- llvm::EmitUnwindInfo(streamer, info);
-}
+namespace Win64EH {
+void UnwindEmitter::Emit(MCStreamer &Streamer) const {
+ MCContext &Context = Streamer.getContext();
-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 (const auto &CFI : Streamer.getWinFrameInfos()) {
+ const MCSection *XData =
+ getXDataSection(CFI->Function, Context);
+ Streamer.SwitchSection(XData);
+ EmitUnwindInfo(Streamer, CFI);
+ }
+
// 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 (const auto &CFI : Streamer.getWinFrameInfos()) {
+ const MCSection *PData =
+ getPDataSection(CFI->Function, Context);
+ Streamer.SwitchSection(PData);
+ EmitRuntimeFunction(Streamer, CFI);
+ }
}
+void UnwindEmitter::EmitUnwindInfo(MCStreamer &Streamer,
+ WinEH::FrameInfo *info) const {
+ // Switch sections (the static function above is meant to be called from
+ // here and from Emit().
+ MCContext &context = Streamer.getContext();
+ const MCSection *xdataSect =
+ getXDataSection(info->Function, context);
+ Streamer.SwitchSection(xdataSect);
+
+ llvm::EmitUnwindInfo(Streamer, info);
+}
+}
} // End of namespace llvm