lib/MC/MCXCOFFStreamer.cpp

   1 //===- lib/MC/MCXCOFFStreamer.cpp - XCOFF Object Output -------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file assembles .s files and emits XCOFF .o object files.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "llvm/BinaryFormat/XCOFF.h"
  14 #include "llvm/MC/MCAsmBackend.h"
  15 #include "llvm/MC/MCCodeEmitter.h"
  16 #include "llvm/MC/MCObjectWriter.h"
  17 #include "llvm/MC/MCSymbolXCOFF.h"
  18 #include "llvm/MC/MCXCOFFStreamer.h"
  19 #include "llvm/Support/TargetRegistry.h"
  20
  21 using namespace llvm;
  22
  23 MCXCOFFStreamer::MCXCOFFStreamer(MCContext &Context,
  24                                  std::unique_ptr<MCAsmBackend> MAB,
  25                                  std::unique_ptr<MCObjectWriter> OW,
  26                                  std::unique_ptr<MCCodeEmitter> Emitter)
  27     : MCObjectStreamer(Context, std::move(MAB), std::move(OW),
  28                        std::move(Emitter)) {}
  29
  30 bool MCXCOFFStreamer::EmitSymbolAttribute(MCSymbol *Sym,
  31                                           MCSymbolAttr Attribute) {
  32   auto *Symbol = cast<MCSymbolXCOFF>(Sym);
  33   getAssembler().registerSymbol(*Symbol);
  34
  35   switch (Attribute) {
  36   case MCSA_Global:
  37     Symbol->setStorageClass(XCOFF::C_EXT);
  38     Symbol->setExternal(true);
  39     break;
  40   default:
  41     report_fatal_error("Not implemented yet.");
  42   }
  43   return true;
  44 }
  45
  46 void MCXCOFFStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
  47                                        unsigned ByteAlignment) {
  48   getAssembler().registerSymbol(*Symbol);
  49   Symbol->setExternal(cast<MCSymbolXCOFF>(Symbol)->getStorageClass() !=
  50                       XCOFF::C_HIDEXT);
  51   Symbol->setCommon(Size, ByteAlignment);
  52
  53   // Need to add this symbol to the current Fragment which will belong to the
  54   // containing CSECT.
  55   auto *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
  56   assert(F && "Expected a valid section with a fragment set.");
  57   Symbol->setFragment(F);
  58
  59   // Emit the alignment and storage for the variable to the section.
  60   EmitValueToAlignment(ByteAlignment);
  61   EmitZeros(Size);
  62 }
  63
  64 void MCXCOFFStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
  65                                    uint64_t Size, unsigned ByteAlignment,
  66                                    SMLoc Loc) {
  67   report_fatal_error("Zero fill not implemented for XCOFF.");
  68 }
  69
  70 void MCXCOFFStreamer::EmitInstToData(const MCInst &Inst,
  71                                      const MCSubtargetInfo &STI) {
  72   MCAssembler &Assembler = getAssembler();
  73   SmallVector<MCFixup, 4> Fixups;
  74   SmallString<256> Code;
  75   raw_svector_ostream VecOS(Code);
  76   Assembler.getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
  77
  78   // TODO: Handle Fixups later
  79
  80   MCDataFragment *DF = getOrCreateDataFragment(&STI);
  81   DF->setHasInstructions(STI);
  82   DF->getContents().append(Code.begin(), Code.end());
  83 }
  84
  85 MCStreamer *llvm::createXCOFFStreamer(MCContext &Context,
  86                                       std::unique_ptr<MCAsmBackend> &&MAB,
  87                                       std::unique_ptr<MCObjectWriter> &&OW,
  88                                       std::unique_ptr<MCCodeEmitter> &&CE,
  89                                       bool RelaxAll) {
  90   MCXCOFFStreamer *S = new MCXCOFFStreamer(Context, std::move(MAB),
  91                                            std::move(OW), std::move(CE));
  92   if (RelaxAll)
  93     S->getAssembler().setRelaxAll(true);
  94   return S;
  95 }
  96
  97 void MCXCOFFStreamer::EmitXCOFFLocalCommonSymbol(MCSymbol *Symbol,
  98                                                  uint64_t Size,
  99                                                  unsigned ByteAlignment) {
 100   EmitCommonSymbol(Symbol, Size, ByteAlignment);
 101 }