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/MC/MCXCOFFStreamer.h"
14 #include "llvm/BinaryFormat/XCOFF.h"
15 #include "llvm/MC/MCAsmBackend.h"
16 #include "llvm/MC/MCCodeEmitter.h"
17 #include "llvm/MC/MCDirectives.h"
18 #include "llvm/MC/MCObjectWriter.h"
19 #include "llvm/MC/MCSectionXCOFF.h"
20 #include "llvm/MC/MCSymbolXCOFF.h"
21 #include "llvm/Support/TargetRegistry.h"
22
23 using namespace llvm;
24
MCXCOFFStreamer(MCContext & Context,std::unique_ptr<MCAsmBackend> MAB,std::unique_ptr<MCObjectWriter> OW,std::unique_ptr<MCCodeEmitter> Emitter)25 MCXCOFFStreamer::MCXCOFFStreamer(MCContext &Context,
26 std::unique_ptr<MCAsmBackend> MAB,
27 std::unique_ptr<MCObjectWriter> OW,
28 std::unique_ptr<MCCodeEmitter> Emitter)
29 : MCObjectStreamer(Context, std::move(MAB), std::move(OW),
30 std::move(Emitter)) {}
31
emitSymbolAttribute(MCSymbol * Sym,MCSymbolAttr Attribute)32 bool MCXCOFFStreamer::emitSymbolAttribute(MCSymbol *Sym,
33 MCSymbolAttr Attribute) {
34 auto *Symbol = cast<MCSymbolXCOFF>(Sym);
35 getAssembler().registerSymbol(*Symbol);
36
37 switch (Attribute) {
38 case MCSA_Global:
39 case MCSA_Extern:
40 Symbol->setStorageClass(XCOFF::C_EXT);
41 Symbol->setExternal(true);
42 break;
43 case MCSA_LGlobal:
44 Symbol->setStorageClass(XCOFF::C_HIDEXT);
45 Symbol->setExternal(true);
46 break;
47 case llvm::MCSA_Weak:
48 Symbol->setStorageClass(XCOFF::C_WEAKEXT);
49 Symbol->setExternal(true);
50 break;
51 case llvm::MCSA_Hidden:
52 Symbol->setVisibilityType(XCOFF::SYM_V_HIDDEN);
53 break;
54 case llvm::MCSA_Protected:
55 Symbol->setVisibilityType(XCOFF::SYM_V_PROTECTED);
56 break;
57 default:
58 report_fatal_error("Not implemented yet.");
59 }
60 return true;
61 }
62
emitXCOFFSymbolLinkageWithVisibility(MCSymbol * Symbol,MCSymbolAttr Linkage,MCSymbolAttr Visibility)63 void MCXCOFFStreamer::emitXCOFFSymbolLinkageWithVisibility(
64 MCSymbol *Symbol, MCSymbolAttr Linkage, MCSymbolAttr Visibility) {
65
66 emitSymbolAttribute(Symbol, Linkage);
67
68 // When the caller passes `MCSA_Invalid` for the visibility, do not emit one.
69 if (Visibility == MCSA_Invalid)
70 return;
71
72 emitSymbolAttribute(Symbol, Visibility);
73 }
74
emitCommonSymbol(MCSymbol * Symbol,uint64_t Size,unsigned ByteAlignment)75 void MCXCOFFStreamer::emitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
76 unsigned ByteAlignment) {
77 getAssembler().registerSymbol(*Symbol);
78 Symbol->setExternal(cast<MCSymbolXCOFF>(Symbol)->getStorageClass() !=
79 XCOFF::C_HIDEXT);
80 Symbol->setCommon(Size, ByteAlignment);
81
82 // Default csect align is 4, but common symbols have explicit alignment values
83 // and we should honor it.
84 cast<MCSymbolXCOFF>(Symbol)->getRepresentedCsect()->setAlignment(
85 Align(ByteAlignment));
86
87 // Emit the alignment and storage for the variable to the section.
88 emitValueToAlignment(ByteAlignment);
89 emitZeros(Size);
90 }
91
emitZerofill(MCSection * Section,MCSymbol * Symbol,uint64_t Size,unsigned ByteAlignment,SMLoc Loc)92 void MCXCOFFStreamer::emitZerofill(MCSection *Section, MCSymbol *Symbol,
93 uint64_t Size, unsigned ByteAlignment,
94 SMLoc Loc) {
95 report_fatal_error("Zero fill not implemented for XCOFF.");
96 }
97
emitInstToData(const MCInst & Inst,const MCSubtargetInfo & STI)98 void MCXCOFFStreamer::emitInstToData(const MCInst &Inst,
99 const MCSubtargetInfo &STI) {
100 MCAssembler &Assembler = getAssembler();
101 SmallVector<MCFixup, 4> Fixups;
102 SmallString<256> Code;
103 raw_svector_ostream VecOS(Code);
104 Assembler.getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
105
106 // Add the fixups and data.
107 MCDataFragment *DF = getOrCreateDataFragment(&STI);
108 const size_t ContentsSize = DF->getContents().size();
109 auto &DataFragmentFixups = DF->getFixups();
110 for (auto &Fixup : Fixups) {
111 Fixup.setOffset(Fixup.getOffset() + ContentsSize);
112 DataFragmentFixups.push_back(Fixup);
113 }
114
115 DF->setHasInstructions(STI);
116 DF->getContents().append(Code.begin(), Code.end());
117 }
118
createXCOFFStreamer(MCContext & Context,std::unique_ptr<MCAsmBackend> && MAB,std::unique_ptr<MCObjectWriter> && OW,std::unique_ptr<MCCodeEmitter> && CE,bool RelaxAll)119 MCStreamer *llvm::createXCOFFStreamer(MCContext &Context,
120 std::unique_ptr<MCAsmBackend> &&MAB,
121 std::unique_ptr<MCObjectWriter> &&OW,
122 std::unique_ptr<MCCodeEmitter> &&CE,
123 bool RelaxAll) {
124 MCXCOFFStreamer *S = new MCXCOFFStreamer(Context, std::move(MAB),
125 std::move(OW), std::move(CE));
126 if (RelaxAll)
127 S->getAssembler().setRelaxAll(true);
128 return S;
129 }
130
emitXCOFFLocalCommonSymbol(MCSymbol * LabelSym,uint64_t Size,MCSymbol * CsectSym,unsigned ByteAlignment)131 void MCXCOFFStreamer::emitXCOFFLocalCommonSymbol(MCSymbol *LabelSym,
132 uint64_t Size,
133 MCSymbol *CsectSym,
134 unsigned ByteAlignment) {
135 emitCommonSymbol(CsectSym, Size, ByteAlignment);
136 }
137