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644 lines
21 KiB
C++
644 lines
21 KiB
C++
//===- lib/MC/MCWin64EH.cpp - MCWin64EH implementation --------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/MC/MCWin64EH.h"
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#include "llvm/ADT/Twine.h"
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#include "llvm/MC/MCContext.h"
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#include "llvm/MC/MCExpr.h"
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#include "llvm/MC/MCObjectFileInfo.h"
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#include "llvm/MC/MCObjectStreamer.h"
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#include "llvm/MC/MCSectionCOFF.h"
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#include "llvm/MC/MCStreamer.h"
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#include "llvm/MC/MCSymbol.h"
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#include "llvm/Support/Win64EH.h"
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using namespace llvm;
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// NOTE: All relocations generated here are 4-byte image-relative.
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static uint8_t CountOfUnwindCodes(std::vector<WinEH::Instruction> &Insns) {
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uint8_t Count = 0;
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for (const auto &I : Insns) {
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switch (static_cast<Win64EH::UnwindOpcodes>(I.Operation)) {
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default:
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llvm_unreachable("Unsupported unwind code");
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case Win64EH::UOP_PushNonVol:
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case Win64EH::UOP_AllocSmall:
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case Win64EH::UOP_SetFPReg:
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case Win64EH::UOP_PushMachFrame:
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Count += 1;
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break;
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case Win64EH::UOP_SaveNonVol:
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case Win64EH::UOP_SaveXMM128:
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Count += 2;
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break;
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case Win64EH::UOP_SaveNonVolBig:
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case Win64EH::UOP_SaveXMM128Big:
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Count += 3;
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break;
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case Win64EH::UOP_AllocLarge:
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Count += (I.Offset > 512 * 1024 - 8) ? 3 : 2;
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break;
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}
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}
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return Count;
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}
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static void EmitAbsDifference(MCStreamer &Streamer, const MCSymbol *LHS,
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const MCSymbol *RHS) {
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MCContext &Context = Streamer.getContext();
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const MCExpr *Diff =
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MCBinaryExpr::createSub(MCSymbolRefExpr::create(LHS, Context),
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MCSymbolRefExpr::create(RHS, Context), Context);
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Streamer.EmitValue(Diff, 1);
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}
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static void EmitUnwindCode(MCStreamer &streamer, const MCSymbol *begin,
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WinEH::Instruction &inst) {
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uint8_t b2;
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uint16_t w;
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b2 = (inst.Operation & 0x0F);
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switch (static_cast<Win64EH::UnwindOpcodes>(inst.Operation)) {
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default:
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llvm_unreachable("Unsupported unwind code");
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case Win64EH::UOP_PushNonVol:
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EmitAbsDifference(streamer, inst.Label, begin);
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b2 |= (inst.Register & 0x0F) << 4;
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streamer.EmitIntValue(b2, 1);
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break;
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case Win64EH::UOP_AllocLarge:
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EmitAbsDifference(streamer, inst.Label, begin);
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if (inst.Offset > 512 * 1024 - 8) {
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b2 |= 0x10;
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streamer.EmitIntValue(b2, 1);
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w = inst.Offset & 0xFFF8;
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streamer.EmitIntValue(w, 2);
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w = inst.Offset >> 16;
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} else {
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streamer.EmitIntValue(b2, 1);
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w = inst.Offset >> 3;
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}
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streamer.EmitIntValue(w, 2);
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break;
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case Win64EH::UOP_AllocSmall:
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b2 |= (((inst.Offset - 8) >> 3) & 0x0F) << 4;
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EmitAbsDifference(streamer, inst.Label, begin);
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streamer.EmitIntValue(b2, 1);
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break;
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case Win64EH::UOP_SetFPReg:
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EmitAbsDifference(streamer, inst.Label, begin);
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streamer.EmitIntValue(b2, 1);
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break;
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case Win64EH::UOP_SaveNonVol:
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case Win64EH::UOP_SaveXMM128:
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b2 |= (inst.Register & 0x0F) << 4;
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EmitAbsDifference(streamer, inst.Label, begin);
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streamer.EmitIntValue(b2, 1);
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w = inst.Offset >> 3;
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if (inst.Operation == Win64EH::UOP_SaveXMM128)
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w >>= 1;
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streamer.EmitIntValue(w, 2);
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break;
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case Win64EH::UOP_SaveNonVolBig:
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case Win64EH::UOP_SaveXMM128Big:
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b2 |= (inst.Register & 0x0F) << 4;
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EmitAbsDifference(streamer, inst.Label, begin);
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streamer.EmitIntValue(b2, 1);
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if (inst.Operation == Win64EH::UOP_SaveXMM128Big)
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w = inst.Offset & 0xFFF0;
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else
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w = inst.Offset & 0xFFF8;
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streamer.EmitIntValue(w, 2);
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w = inst.Offset >> 16;
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streamer.EmitIntValue(w, 2);
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break;
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case Win64EH::UOP_PushMachFrame:
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if (inst.Offset == 1)
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b2 |= 0x10;
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EmitAbsDifference(streamer, inst.Label, begin);
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streamer.EmitIntValue(b2, 1);
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break;
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}
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}
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static void EmitSymbolRefWithOfs(MCStreamer &streamer,
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const MCSymbol *Base,
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const MCSymbol *Other) {
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MCContext &Context = streamer.getContext();
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const MCSymbolRefExpr *BaseRef = MCSymbolRefExpr::create(Base, Context);
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const MCSymbolRefExpr *OtherRef = MCSymbolRefExpr::create(Other, Context);
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const MCExpr *Ofs = MCBinaryExpr::createSub(OtherRef, BaseRef, Context);
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const MCSymbolRefExpr *BaseRefRel = MCSymbolRefExpr::create(Base,
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MCSymbolRefExpr::VK_COFF_IMGREL32,
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Context);
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streamer.EmitValue(MCBinaryExpr::createAdd(BaseRefRel, Ofs, Context), 4);
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}
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static void EmitRuntimeFunction(MCStreamer &streamer,
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const WinEH::FrameInfo *info) {
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MCContext &context = streamer.getContext();
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streamer.EmitValueToAlignment(4);
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EmitSymbolRefWithOfs(streamer, info->Function, info->Begin);
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EmitSymbolRefWithOfs(streamer, info->Function, info->End);
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streamer.EmitValue(MCSymbolRefExpr::create(info->Symbol,
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MCSymbolRefExpr::VK_COFF_IMGREL32,
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context), 4);
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}
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static void EmitUnwindInfo(MCStreamer &streamer, WinEH::FrameInfo *info) {
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// If this UNWIND_INFO already has a symbol, it's already been emitted.
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if (info->Symbol)
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return;
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MCContext &context = streamer.getContext();
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MCSymbol *Label = context.createTempSymbol();
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streamer.EmitValueToAlignment(4);
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streamer.EmitLabel(Label);
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info->Symbol = Label;
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// Upper 3 bits are the version number (currently 1).
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uint8_t flags = 0x01;
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if (info->ChainedParent)
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flags |= Win64EH::UNW_ChainInfo << 3;
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else {
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if (info->HandlesUnwind)
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flags |= Win64EH::UNW_TerminateHandler << 3;
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if (info->HandlesExceptions)
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flags |= Win64EH::UNW_ExceptionHandler << 3;
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}
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streamer.EmitIntValue(flags, 1);
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if (info->PrologEnd)
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EmitAbsDifference(streamer, info->PrologEnd, info->Begin);
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else
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streamer.EmitIntValue(0, 1);
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uint8_t numCodes = CountOfUnwindCodes(info->Instructions);
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streamer.EmitIntValue(numCodes, 1);
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uint8_t frame = 0;
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if (info->LastFrameInst >= 0) {
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WinEH::Instruction &frameInst = info->Instructions[info->LastFrameInst];
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assert(frameInst.Operation == Win64EH::UOP_SetFPReg);
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frame = (frameInst.Register & 0x0F) | (frameInst.Offset & 0xF0);
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}
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streamer.EmitIntValue(frame, 1);
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// Emit unwind instructions (in reverse order).
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uint8_t numInst = info->Instructions.size();
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for (uint8_t c = 0; c < numInst; ++c) {
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WinEH::Instruction inst = info->Instructions.back();
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info->Instructions.pop_back();
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EmitUnwindCode(streamer, info->Begin, inst);
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}
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// For alignment purposes, the instruction array will always have an even
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// number of entries, with the final entry potentially unused (in which case
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// the array will be one longer than indicated by the count of unwind codes
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// field).
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if (numCodes & 1) {
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streamer.EmitIntValue(0, 2);
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}
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if (flags & (Win64EH::UNW_ChainInfo << 3))
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EmitRuntimeFunction(streamer, info->ChainedParent);
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else if (flags &
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((Win64EH::UNW_TerminateHandler|Win64EH::UNW_ExceptionHandler) << 3))
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streamer.EmitValue(MCSymbolRefExpr::create(info->ExceptionHandler,
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MCSymbolRefExpr::VK_COFF_IMGREL32,
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context), 4);
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else if (numCodes == 0) {
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// The minimum size of an UNWIND_INFO struct is 8 bytes. If we're not
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// a chained unwind info, if there is no handler, and if there are fewer
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// than 2 slots used in the unwind code array, we have to pad to 8 bytes.
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streamer.EmitIntValue(0, 4);
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}
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}
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void llvm::Win64EH::UnwindEmitter::Emit(MCStreamer &Streamer) const {
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// Emit the unwind info structs first.
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for (const auto &CFI : Streamer.getWinFrameInfos()) {
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MCSection *XData = Streamer.getAssociatedXDataSection(CFI->TextSection);
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Streamer.SwitchSection(XData);
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::EmitUnwindInfo(Streamer, CFI.get());
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}
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// Now emit RUNTIME_FUNCTION entries.
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for (const auto &CFI : Streamer.getWinFrameInfos()) {
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MCSection *PData = Streamer.getAssociatedPDataSection(CFI->TextSection);
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Streamer.SwitchSection(PData);
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EmitRuntimeFunction(Streamer, CFI.get());
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}
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}
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void llvm::Win64EH::UnwindEmitter::EmitUnwindInfo(
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MCStreamer &Streamer, WinEH::FrameInfo *info) const {
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// Switch sections (the static function above is meant to be called from
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// here and from Emit().
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MCSection *XData = Streamer.getAssociatedXDataSection(info->TextSection);
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Streamer.SwitchSection(XData);
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::EmitUnwindInfo(Streamer, info);
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}
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static int64_t GetAbsDifference(MCStreamer &Streamer, const MCSymbol *LHS,
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const MCSymbol *RHS) {
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MCContext &Context = Streamer.getContext();
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const MCExpr *Diff =
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MCBinaryExpr::createSub(MCSymbolRefExpr::create(LHS, Context),
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MCSymbolRefExpr::create(RHS, Context), Context);
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MCObjectStreamer *OS = (MCObjectStreamer *)(&Streamer);
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int64_t value;
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Diff->evaluateAsAbsolute(value, OS->getAssembler());
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return value;
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}
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static uint32_t
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ARM64CountOfUnwindCodes(const std::vector<WinEH::Instruction> &Insns) {
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uint32_t Count = 0;
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for (const auto &I : Insns) {
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switch (static_cast<Win64EH::UnwindOpcodes>(I.Operation)) {
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default:
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llvm_unreachable("Unsupported ARM64 unwind code");
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case Win64EH::UOP_AllocSmall:
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Count += 1;
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break;
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case Win64EH::UOP_AllocMedium:
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Count += 2;
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break;
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case Win64EH::UOP_AllocLarge:
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Count += 4;
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break;
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case Win64EH::UOP_SaveFPLRX:
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Count += 1;
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break;
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case Win64EH::UOP_SaveFPLR:
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Count += 1;
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break;
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case Win64EH::UOP_SaveReg:
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Count += 2;
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break;
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case Win64EH::UOP_SaveRegP:
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Count += 2;
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break;
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case Win64EH::UOP_SaveRegPX:
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Count += 2;
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break;
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case Win64EH::UOP_SaveRegX:
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Count += 2;
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break;
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case Win64EH::UOP_SaveFReg:
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Count += 2;
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break;
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case Win64EH::UOP_SaveFRegP:
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Count += 2;
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break;
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case Win64EH::UOP_SaveFRegX:
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Count += 2;
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break;
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case Win64EH::UOP_SaveFRegPX:
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Count += 2;
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break;
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case Win64EH::UOP_SetFP:
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Count += 1;
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break;
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case Win64EH::UOP_AddFP:
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Count += 2;
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break;
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case Win64EH::UOP_Nop:
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Count += 1;
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break;
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case Win64EH::UOP_End:
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Count += 1;
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break;
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}
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}
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return Count;
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}
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// Unwind opcode encodings and restrictions are documented at
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// https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling
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static void ARM64EmitUnwindCode(MCStreamer &streamer, const MCSymbol *begin,
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WinEH::Instruction &inst) {
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uint8_t b, reg;
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switch (static_cast<Win64EH::UnwindOpcodes>(inst.Operation)) {
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default:
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llvm_unreachable("Unsupported ARM64 unwind code");
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case Win64EH::UOP_AllocSmall:
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b = (inst.Offset >> 4) & 0x1F;
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_AllocMedium: {
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uint16_t hw = (inst.Offset >> 4) & 0x7FF;
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b = 0xC0;
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b |= (hw >> 8);
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streamer.EmitIntValue(b, 1);
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b = hw & 0xFF;
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streamer.EmitIntValue(b, 1);
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break;
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}
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case Win64EH::UOP_AllocLarge: {
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uint32_t w;
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b = 0xE0;
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streamer.EmitIntValue(b, 1);
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w = inst.Offset >> 4;
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b = (w & 0x00FF0000) >> 16;
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streamer.EmitIntValue(b, 1);
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b = (w & 0x0000FF00) >> 8;
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streamer.EmitIntValue(b, 1);
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b = w & 0x000000FF;
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streamer.EmitIntValue(b, 1);
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break;
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}
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case Win64EH::UOP_SetFP:
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b = 0xE1;
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_AddFP:
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b = 0xE2;
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streamer.EmitIntValue(b, 1);
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b = (inst.Offset >> 3);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_Nop:
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b = 0xE3;
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveFPLRX:
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b = 0x80;
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b |= ((inst.Offset - 1) >> 3) & 0x3F;
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveFPLR:
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b = 0x40;
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b |= (inst.Offset >> 3) & 0x3F;
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveReg:
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assert(inst.Register >= 19 && "Saved reg must be >= 19");
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reg = inst.Register - 19;
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b = 0xD0 | ((reg & 0xC) >> 2);
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x3) << 6) | (inst.Offset >> 3);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveRegX:
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assert(inst.Register >= 19 && "Saved reg must be >= 19");
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reg = inst.Register - 19;
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b = 0xD4 | ((reg & 0x8) >> 3);
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x7) << 5) | ((inst.Offset >> 3) - 1);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveRegP:
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assert(inst.Register >= 19 && "Saved registers must be >= 19");
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reg = inst.Register - 19;
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b = 0xC8 | ((reg & 0xC) >> 2);
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x3) << 6) | (inst.Offset >> 3);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveRegPX:
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assert(inst.Register >= 19 && "Saved registers must be >= 19");
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reg = inst.Register - 19;
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b = 0xCC | ((reg & 0xC) >> 2);
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x3) << 6) | ((inst.Offset >> 3) - 1);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveFReg:
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assert(inst.Register >= 8 && "Saved dreg must be >= 8");
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reg = inst.Register - 8;
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b = 0xDC | ((reg & 0x4) >> 2);
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x3) << 6) | (inst.Offset >> 3);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveFRegX:
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assert(inst.Register >= 8 && "Saved dreg must be >= 8");
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reg = inst.Register - 8;
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b = 0xDE;
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x7) << 5) | ((inst.Offset >> 3) - 1);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveFRegP:
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assert(inst.Register >= 8 && "Saved dregs must be >= 8");
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reg = inst.Register - 8;
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b = 0xD8 | ((reg & 0x4) >> 2);
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x3) << 6) | (inst.Offset >> 3);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_SaveFRegPX:
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assert(inst.Register >= 8 && "Saved dregs must be >= 8");
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reg = inst.Register - 8;
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b = 0xDA | ((reg & 0x4) >> 2);
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streamer.EmitIntValue(b, 1);
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b = ((reg & 0x3) << 6) | ((inst.Offset >> 3) - 1);
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streamer.EmitIntValue(b, 1);
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break;
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case Win64EH::UOP_End:
|
|
b = 0xE4;
|
|
streamer.EmitIntValue(b, 1);
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Returns the epilog symbol of an epilog with the exact same unwind code
|
|
// sequence, if it exists. Otherwise, returns nulltpr.
|
|
// EpilogInstrs - Unwind codes for the current epilog.
|
|
// Epilogs - Epilogs that potentialy match the current epilog.
|
|
static MCSymbol*
|
|
FindMatchingEpilog(const std::vector<WinEH::Instruction>& EpilogInstrs,
|
|
const std::vector<MCSymbol *>& Epilogs,
|
|
const WinEH::FrameInfo *info) {
|
|
for (auto *EpilogStart : Epilogs) {
|
|
auto InstrsIter = info->EpilogMap.find(EpilogStart);
|
|
assert(InstrsIter != info->EpilogMap.end() &&
|
|
"Epilog not found in EpilogMap");
|
|
const auto &Instrs = InstrsIter->second;
|
|
|
|
if (Instrs.size() != EpilogInstrs.size())
|
|
continue;
|
|
|
|
bool Match = true;
|
|
for (unsigned i = 0; i < Instrs.size(); ++i)
|
|
if (Instrs[i].Operation != EpilogInstrs[i].Operation ||
|
|
Instrs[i].Offset != EpilogInstrs[i].Offset ||
|
|
Instrs[i].Register != EpilogInstrs[i].Register) {
|
|
Match = false;
|
|
break;
|
|
}
|
|
|
|
if (Match)
|
|
return EpilogStart;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
// Populate the .xdata section. The format of .xdata on ARM64 is documented at
|
|
// https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling
|
|
static void ARM64EmitUnwindInfo(MCStreamer &streamer, WinEH::FrameInfo *info) {
|
|
// If this UNWIND_INFO already has a symbol, it's already been emitted.
|
|
if (info->Symbol)
|
|
return;
|
|
|
|
MCContext &context = streamer.getContext();
|
|
MCSymbol *Label = context.createTempSymbol();
|
|
|
|
streamer.EmitValueToAlignment(4);
|
|
streamer.EmitLabel(Label);
|
|
info->Symbol = Label;
|
|
|
|
uint32_t FuncLength = 0x0;
|
|
if (info->FuncletOrFuncEnd)
|
|
FuncLength = (uint32_t)GetAbsDifference(streamer, info->FuncletOrFuncEnd,
|
|
info->Begin);
|
|
FuncLength /= 4;
|
|
uint32_t PrologCodeBytes = ARM64CountOfUnwindCodes(info->Instructions);
|
|
uint32_t TotalCodeBytes = PrologCodeBytes;
|
|
|
|
// Process epilogs.
|
|
MapVector<MCSymbol *, uint32_t> EpilogInfo;
|
|
// Epilogs processed so far.
|
|
std::vector<MCSymbol *> AddedEpilogs;
|
|
|
|
for (auto &I : info->EpilogMap) {
|
|
MCSymbol *EpilogStart = I.first;
|
|
auto &EpilogInstrs = I.second;
|
|
uint32_t CodeBytes = ARM64CountOfUnwindCodes(EpilogInstrs);
|
|
|
|
MCSymbol* MatchingEpilog =
|
|
FindMatchingEpilog(EpilogInstrs, AddedEpilogs, info);
|
|
if (MatchingEpilog) {
|
|
assert(EpilogInfo.find(MatchingEpilog) != EpilogInfo.end() &&
|
|
"Duplicate epilog not found");
|
|
EpilogInfo[EpilogStart] = EpilogInfo.lookup(MatchingEpilog);
|
|
// Clear the unwind codes in the EpilogMap, so that they don't get output
|
|
// in the logic below.
|
|
EpilogInstrs.clear();
|
|
} else {
|
|
EpilogInfo[EpilogStart] = TotalCodeBytes;
|
|
TotalCodeBytes += CodeBytes;
|
|
AddedEpilogs.push_back(EpilogStart);
|
|
}
|
|
}
|
|
|
|
// Code Words, Epilog count, E, X, Vers, Function Length
|
|
uint32_t row1 = 0x0;
|
|
uint32_t CodeWords = TotalCodeBytes / 4;
|
|
uint32_t CodeWordsMod = TotalCodeBytes % 4;
|
|
if (CodeWordsMod)
|
|
CodeWords++;
|
|
uint32_t EpilogCount = info->EpilogMap.size();
|
|
bool ExtensionWord = EpilogCount > 31 || TotalCodeBytes > 124;
|
|
if (!ExtensionWord) {
|
|
row1 |= (EpilogCount & 0x1F) << 22;
|
|
row1 |= (CodeWords & 0x1F) << 27;
|
|
}
|
|
// E is always 0 right now, TODO: packed epilog setup
|
|
if (info->HandlesExceptions) // X
|
|
row1 |= 1 << 20;
|
|
row1 |= FuncLength & 0x3FFFF;
|
|
streamer.EmitIntValue(row1, 4);
|
|
|
|
// Extended Code Words, Extended Epilog Count
|
|
if (ExtensionWord) {
|
|
// FIXME: We should be able to split unwind info into multiple sections.
|
|
// FIXME: We should share epilog codes across epilogs, where possible,
|
|
// which would make this issue show up less frequently.
|
|
if (CodeWords > 0xFF || EpilogCount > 0xFFFF)
|
|
report_fatal_error("SEH unwind data splitting not yet implemented");
|
|
uint32_t row2 = 0x0;
|
|
row2 |= (CodeWords & 0xFF) << 16;
|
|
row2 |= (EpilogCount & 0xFFFF);
|
|
streamer.EmitIntValue(row2, 4);
|
|
}
|
|
|
|
// Epilog Start Index, Epilog Start Offset
|
|
for (auto &I : EpilogInfo) {
|
|
MCSymbol *EpilogStart = I.first;
|
|
uint32_t EpilogIndex = I.second;
|
|
uint32_t EpilogOffset =
|
|
(uint32_t)GetAbsDifference(streamer, EpilogStart, info->Begin);
|
|
if (EpilogOffset)
|
|
EpilogOffset /= 4;
|
|
uint32_t row3 = EpilogOffset;
|
|
row3 |= (EpilogIndex & 0x3FF) << 22;
|
|
streamer.EmitIntValue(row3, 4);
|
|
}
|
|
|
|
// Emit prolog unwind instructions (in reverse order).
|
|
uint8_t numInst = info->Instructions.size();
|
|
for (uint8_t c = 0; c < numInst; ++c) {
|
|
WinEH::Instruction inst = info->Instructions.back();
|
|
info->Instructions.pop_back();
|
|
ARM64EmitUnwindCode(streamer, info->Begin, inst);
|
|
}
|
|
|
|
// Emit epilog unwind instructions
|
|
for (auto &I : info->EpilogMap) {
|
|
auto &EpilogInstrs = I.second;
|
|
for (uint32_t i = 0; i < EpilogInstrs.size(); i++) {
|
|
WinEH::Instruction inst = EpilogInstrs[i];
|
|
ARM64EmitUnwindCode(streamer, info->Begin, inst);
|
|
}
|
|
}
|
|
|
|
int32_t BytesMod = CodeWords * 4 - TotalCodeBytes;
|
|
assert(BytesMod >= 0);
|
|
for (int i = 0; i < BytesMod; i++)
|
|
streamer.EmitIntValue(0xE3, 1);
|
|
|
|
if (info->HandlesExceptions)
|
|
streamer.EmitValue(
|
|
MCSymbolRefExpr::create(info->ExceptionHandler,
|
|
MCSymbolRefExpr::VK_COFF_IMGREL32, context),
|
|
4);
|
|
}
|
|
|
|
static void ARM64EmitRuntimeFunction(MCStreamer &streamer,
|
|
const WinEH::FrameInfo *info) {
|
|
MCContext &context = streamer.getContext();
|
|
|
|
streamer.EmitValueToAlignment(4);
|
|
EmitSymbolRefWithOfs(streamer, info->Function, info->Begin);
|
|
streamer.EmitValue(MCSymbolRefExpr::create(info->Symbol,
|
|
MCSymbolRefExpr::VK_COFF_IMGREL32,
|
|
context),
|
|
4);
|
|
}
|
|
|
|
void llvm::Win64EH::ARM64UnwindEmitter::Emit(MCStreamer &Streamer) const {
|
|
// Emit the unwind info structs first.
|
|
for (const auto &CFI : Streamer.getWinFrameInfos()) {
|
|
MCSection *XData = Streamer.getAssociatedXDataSection(CFI->TextSection);
|
|
Streamer.SwitchSection(XData);
|
|
ARM64EmitUnwindInfo(Streamer, CFI.get());
|
|
}
|
|
|
|
// Now emit RUNTIME_FUNCTION entries.
|
|
for (const auto &CFI : Streamer.getWinFrameInfos()) {
|
|
MCSection *PData = Streamer.getAssociatedPDataSection(CFI->TextSection);
|
|
Streamer.SwitchSection(PData);
|
|
ARM64EmitRuntimeFunction(Streamer, CFI.get());
|
|
}
|
|
}
|
|
|
|
void llvm::Win64EH::ARM64UnwindEmitter::EmitUnwindInfo(
|
|
MCStreamer &Streamer, WinEH::FrameInfo *info) const {
|
|
// Switch sections (the static function above is meant to be called from
|
|
// here and from Emit().
|
|
MCSection *XData = Streamer.getAssociatedXDataSection(info->TextSection);
|
|
Streamer.SwitchSection(XData);
|
|
ARM64EmitUnwindInfo(Streamer, info);
|
|
}
|