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diff --git a/contrib/llvm/lib/MC/MCWinCOFFStreamer.cpp b/contrib/llvm/lib/MC/MCWinCOFFStreamer.cpp
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+//===- llvm/MC/MCWinCOFFStreamer.cpp --------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains an implementation of a Windows COFF object file streamer.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/BinaryFormat/COFF.h"
+#include "llvm/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCFixup.h"
+#include "llvm/MC/MCFragment.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCObjectStreamer.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCSymbolCOFF.h"
+#include "llvm/MC/MCWinCOFFStreamer.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/SMLoc.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+
+using namespace llvm;
+
+#define DEBUG_TYPE "WinCOFFStreamer"
+
+MCWinCOFFStreamer::MCWinCOFFStreamer(MCContext &Context, MCAsmBackend &MAB,
+ MCCodeEmitter &CE, raw_pwrite_stream &OS)
+ : MCObjectStreamer(Context, MAB, OS, &CE), CurSymbol(nullptr) {}
+
+void MCWinCOFFStreamer::EmitInstToData(const MCInst &Inst,
+ const MCSubtargetInfo &STI) {
+ MCDataFragment *DF = getOrCreateDataFragment();
+
+ SmallVector<MCFixup, 4> Fixups;
+ SmallString<256> Code;
+ raw_svector_ostream VecOS(Code);
+ getAssembler().getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
+
+ // Add the fixups and data.
+ for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
+ Fixups[i].setOffset(Fixups[i].getOffset() + DF->getContents().size());
+ DF->getFixups().push_back(Fixups[i]);
+ }
+
+ DF->getContents().append(Code.begin(), Code.end());
+}
+
+void MCWinCOFFStreamer::InitSections(bool NoExecStack) {
+ // FIXME: this is identical to the ELF one.
+ // This emulates the same behavior of GNU as. This makes it easier
+ // to compare the output as the major sections are in the same order.
+ SwitchSection(getContext().getObjectFileInfo()->getTextSection());
+ EmitCodeAlignment(4);
+
+ SwitchSection(getContext().getObjectFileInfo()->getDataSection());
+ EmitCodeAlignment(4);
+
+ SwitchSection(getContext().getObjectFileInfo()->getBSSSection());
+ EmitCodeAlignment(4);
+
+ SwitchSection(getContext().getObjectFileInfo()->getTextSection());
+}
+
+void MCWinCOFFStreamer::EmitLabel(MCSymbol *S, SMLoc Loc) {
+ auto *Symbol = cast<MCSymbolCOFF>(S);
+ MCObjectStreamer::EmitLabel(Symbol, Loc);
+}
+
+void MCWinCOFFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
+ llvm_unreachable("not implemented");
+}
+
+void MCWinCOFFStreamer::EmitThumbFunc(MCSymbol *Func) {
+ llvm_unreachable("not implemented");
+}
+
+bool MCWinCOFFStreamer::EmitSymbolAttribute(MCSymbol *S,
+ MCSymbolAttr Attribute) {
+ auto *Symbol = cast<MCSymbolCOFF>(S);
+ getAssembler().registerSymbol(*Symbol);
+
+ switch (Attribute) {
+ default: return false;
+ case MCSA_WeakReference:
+ case MCSA_Weak:
+ Symbol->setIsWeakExternal();
+ Symbol->setExternal(true);
+ break;
+ case MCSA_Global:
+ Symbol->setExternal(true);
+ break;
+ case MCSA_AltEntry:
+ llvm_unreachable("COFF doesn't support the .alt_entry attribute");
+ }
+
+ return true;
+}
+
+void MCWinCOFFStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
+ llvm_unreachable("not implemented");
+}
+
+void MCWinCOFFStreamer::BeginCOFFSymbolDef(MCSymbol const *S) {
+ auto *Symbol = cast<MCSymbolCOFF>(S);
+ if (CurSymbol)
+ Error("starting a new symbol definition without completing the "
+ "previous one");
+ CurSymbol = Symbol;
+}
+
+void MCWinCOFFStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {
+ if (!CurSymbol) {
+ Error("storage class specified outside of symbol definition");
+ return;
+ }
+
+ if (StorageClass & ~COFF::SSC_Invalid) {
+ Error("storage class value '" + Twine(StorageClass) +
+ "' out of range");
+ return;
+ }
+
+ getAssembler().registerSymbol(*CurSymbol);
+ cast<MCSymbolCOFF>(CurSymbol)->setClass((uint16_t)StorageClass);
+}
+
+void MCWinCOFFStreamer::EmitCOFFSymbolType(int Type) {
+ if (!CurSymbol) {
+ Error("symbol type specified outside of a symbol definition");
+ return;
+ }
+
+ if (Type & ~0xffff) {
+ Error("type value '" + Twine(Type) + "' out of range");
+ return;
+ }
+
+ getAssembler().registerSymbol(*CurSymbol);
+ cast<MCSymbolCOFF>(CurSymbol)->setType((uint16_t)Type);
+}
+
+void MCWinCOFFStreamer::EndCOFFSymbolDef() {
+ if (!CurSymbol)
+ Error("ending symbol definition without starting one");
+ CurSymbol = nullptr;
+}
+
+void MCWinCOFFStreamer::EmitCOFFSafeSEH(MCSymbol const *Symbol) {
+ // SafeSEH is a feature specific to 32-bit x86. It does not exist (and is
+ // unnecessary) on all platforms which use table-based exception dispatch.
+ if (getContext().getObjectFileInfo()->getTargetTriple().getArch() !=
+ Triple::x86)
+ return;
+
+ const MCSymbolCOFF *CSymbol = cast<MCSymbolCOFF>(Symbol);
+ if (CSymbol->isSafeSEH())
+ return;
+
+ MCSection *SXData = getContext().getObjectFileInfo()->getSXDataSection();
+ getAssembler().registerSection(*SXData);
+ if (SXData->getAlignment() < 4)
+ SXData->setAlignment(4);
+
+ new MCSafeSEHFragment(Symbol, SXData);
+
+ getAssembler().registerSymbol(*Symbol);
+ CSymbol->setIsSafeSEH();
+
+ // The Microsoft linker requires that the symbol type of a handler be
+ // function. Go ahead and oblige it here.
+ CSymbol->setType(COFF::IMAGE_SYM_DTYPE_FUNCTION
+ << COFF::SCT_COMPLEX_TYPE_SHIFT);
+}
+
+void MCWinCOFFStreamer::EmitCOFFSectionIndex(const MCSymbol *Symbol) {
+ visitUsedSymbol(*Symbol);
+ MCDataFragment *DF = getOrCreateDataFragment();
+ const MCSymbolRefExpr *SRE = MCSymbolRefExpr::create(Symbol, getContext());
+ MCFixup Fixup = MCFixup::create(DF->getContents().size(), SRE, FK_SecRel_2);
+ DF->getFixups().push_back(Fixup);
+ DF->getContents().resize(DF->getContents().size() + 2, 0);
+}
+
+void MCWinCOFFStreamer::EmitCOFFSecRel32(const MCSymbol *Symbol,
+ uint64_t Offset) {
+ visitUsedSymbol(*Symbol);
+ MCDataFragment *DF = getOrCreateDataFragment();
+ // Create Symbol A for the relocation relative reference.
+ const MCExpr *MCE = MCSymbolRefExpr::create(Symbol, getContext());
+ // Add the constant offset, if given.
+ if (Offset)
+ MCE = MCBinaryExpr::createAdd(
+ MCE, MCConstantExpr::create(Offset, getContext()), getContext());
+ // Build the secrel32 relocation.
+ MCFixup Fixup = MCFixup::create(DF->getContents().size(), MCE, FK_SecRel_4);
+ // Record the relocation.
+ DF->getFixups().push_back(Fixup);
+ // Emit 4 bytes (zeros) to the object file.
+ DF->getContents().resize(DF->getContents().size() + 4, 0);
+}
+
+void MCWinCOFFStreamer::EmitCommonSymbol(MCSymbol *S, uint64_t Size,
+ unsigned ByteAlignment) {
+ auto *Symbol = cast<MCSymbolCOFF>(S);
+
+ const Triple &T = getContext().getObjectFileInfo()->getTargetTriple();
+ if (T.isKnownWindowsMSVCEnvironment()) {
+ if (ByteAlignment > 32)
+ report_fatal_error("alignment is limited to 32-bytes");
+
+ // Round size up to alignment so that we will honor the alignment request.
+ Size = std::max(Size, static_cast<uint64_t>(ByteAlignment));
+ }
+
+ getAssembler().registerSymbol(*Symbol);
+ Symbol->setExternal(true);
+ Symbol->setCommon(Size, ByteAlignment);
+
+ if (!T.isKnownWindowsMSVCEnvironment() && ByteAlignment > 1) {
+ SmallString<128> Directive;
+ raw_svector_ostream OS(Directive);
+ const MCObjectFileInfo *MFI = getContext().getObjectFileInfo();
+
+ OS << " -aligncomm:\"" << Symbol->getName() << "\","
+ << Log2_32_Ceil(ByteAlignment);
+
+ PushSection();
+ SwitchSection(MFI->getDrectveSection());
+ EmitBytes(Directive);
+ PopSection();
+ }
+}
+
+void MCWinCOFFStreamer::EmitLocalCommonSymbol(MCSymbol *S, uint64_t Size,
+ unsigned ByteAlignment) {
+ auto *Symbol = cast<MCSymbolCOFF>(S);
+
+ MCSection *Section = getContext().getObjectFileInfo()->getBSSSection();
+ getAssembler().registerSection(*Section);
+ if (Section->getAlignment() < ByteAlignment)
+ Section->setAlignment(ByteAlignment);
+
+ getAssembler().registerSymbol(*Symbol);
+ Symbol->setExternal(false);
+
+ if (ByteAlignment != 1)
+ new MCAlignFragment(ByteAlignment, /*Value=*/0, /*ValueSize=*/0,
+ ByteAlignment, Section);
+
+ MCFillFragment *Fragment = new MCFillFragment(
+ /*Value=*/0, Size, Section);
+ Symbol->setFragment(Fragment);
+}
+
+void MCWinCOFFStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
+ uint64_t Size, unsigned ByteAlignment) {
+ llvm_unreachable("not implemented");
+}
+
+void MCWinCOFFStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
+ uint64_t Size, unsigned ByteAlignment) {
+ llvm_unreachable("not implemented");
+}
+
+// TODO: Implement this if you want to emit .comment section in COFF obj files.
+void MCWinCOFFStreamer::EmitIdent(StringRef IdentString) {
+ llvm_unreachable("not implemented");
+}
+
+void MCWinCOFFStreamer::EmitWinEHHandlerData() {
+ llvm_unreachable("not implemented");
+}
+
+void MCWinCOFFStreamer::FinishImpl() {
+ MCObjectStreamer::FinishImpl();
+}
+
+void MCWinCOFFStreamer::Error(const Twine &Msg) const {
+ getContext().reportError(SMLoc(), Msg);
+}
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