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   // Emit the alignment and storage for the variable to the section.
54   EmitValueToAlignment(ByteAlignment);
55   EmitZeros(Size);
56 }
57 
58 void MCXCOFFStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
59                                    uint64_t Size, unsigned ByteAlignment,
60                                    SMLoc Loc) {
61   report_fatal_error("Zero fill not implemented for XCOFF.");
62 }
63 
64 void MCXCOFFStreamer::EmitInstToData(const MCInst &Inst,
65                                      const MCSubtargetInfo &STI) {
66   MCAssembler &Assembler = getAssembler();
67   SmallVector<MCFixup, 4> Fixups;
68   SmallString<256> Code;
69   raw_svector_ostream VecOS(Code);
70   Assembler.getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
71 
72   // TODO: Handle Fixups later
73 
74   MCDataFragment *DF = getOrCreateDataFragment(&STI);
75   DF->setHasInstructions(STI);
76   DF->getContents().append(Code.begin(), Code.end());
77 }
78 
79 MCStreamer *llvm::createXCOFFStreamer(MCContext &Context,
80                                       std::unique_ptr<MCAsmBackend> &&MAB,
81                                       std::unique_ptr<MCObjectWriter> &&OW,
82                                       std::unique_ptr<MCCodeEmitter> &&CE,
83                                       bool RelaxAll) {
84   MCXCOFFStreamer *S = new MCXCOFFStreamer(Context, std::move(MAB),
85                                            std::move(OW), std::move(CE));
86   if (RelaxAll)
87     S->getAssembler().setRelaxAll(true);
88   return S;
89 }
90 
91 void MCXCOFFStreamer::EmitXCOFFLocalCommonSymbol(MCSymbol *LabelSym,
92                                                  uint64_t Size,
93                                                  MCSymbol *CsectSym,
94                                                  unsigned ByteAlignment) {
95   EmitCommonSymbol(CsectSym, Size, ByteAlignment);
96 }
97