1 //===- lib/MC/MCSectionCOFF.cpp - COFF Code Section Representation --------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "llvm/MC/MCSectionCOFF.h"
11 #include "llvm/MC/MCAsmInfo.h"
12 #include "llvm/MC/MCContext.h"
13 #include "llvm/MC/MCSymbol.h"
14 #include "llvm/Support/raw_ostream.h"
15 using namespace llvm;
16
~MCSectionCOFF()17 MCSectionCOFF::~MCSectionCOFF() {} // anchor.
18
19 // ShouldOmitSectionDirective - Decides whether a '.section' directive
20 // should be printed before the section name
ShouldOmitSectionDirective(StringRef Name,const MCAsmInfo & MAI) const21 bool MCSectionCOFF::ShouldOmitSectionDirective(StringRef Name,
22 const MCAsmInfo &MAI) const {
23 if (COMDATSymbol)
24 return false;
25
26 // FIXME: Does .section .bss/.data/.text work everywhere??
27 if (Name == ".text" || Name == ".data" || Name == ".bss")
28 return true;
29
30 return false;
31 }
32
setSelection(int Selection) const33 void MCSectionCOFF::setSelection(int Selection) const {
34 assert(Selection != 0 && "invalid COMDAT selection type");
35 this->Selection = Selection;
36 Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
37 }
38
PrintSwitchToSection(const MCAsmInfo & MAI,raw_ostream & OS,const MCExpr * Subsection) const39 void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI,
40 raw_ostream &OS,
41 const MCExpr *Subsection) const {
42
43 // standard sections don't require the '.section'
44 if (ShouldOmitSectionDirective(SectionName, MAI)) {
45 OS << '\t' << getSectionName() << '\n';
46 return;
47 }
48
49 OS << "\t.section\t" << getSectionName() << ",\"";
50 if (getCharacteristics() & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
51 OS << 'd';
52 if (getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
53 OS << 'b';
54 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_EXECUTE)
55 OS << 'x';
56 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_WRITE)
57 OS << 'w';
58 else if (getCharacteristics() & COFF::IMAGE_SCN_MEM_READ)
59 OS << 'r';
60 else
61 OS << 'y';
62 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_REMOVE)
63 OS << 'n';
64 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_SHARED)
65 OS << 's';
66 OS << '"';
67
68 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_COMDAT) {
69 OS << ",";
70 switch (Selection) {
71 case COFF::IMAGE_COMDAT_SELECT_NODUPLICATES:
72 OS << "one_only,";
73 break;
74 case COFF::IMAGE_COMDAT_SELECT_ANY:
75 OS << "discard,";
76 break;
77 case COFF::IMAGE_COMDAT_SELECT_SAME_SIZE:
78 OS << "same_size,";
79 break;
80 case COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH:
81 OS << "same_contents,";
82 break;
83 case COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE:
84 OS << "associative,";
85 break;
86 case COFF::IMAGE_COMDAT_SELECT_LARGEST:
87 OS << "largest,";
88 break;
89 case COFF::IMAGE_COMDAT_SELECT_NEWEST:
90 OS << "newest,";
91 break;
92 default:
93 assert (0 && "unsupported COFF selection type");
94 break;
95 }
96 assert(COMDATSymbol);
97 OS << *COMDATSymbol;
98 }
99 OS << '\n';
100 }
101
UseCodeAlign() const102 bool MCSectionCOFF::UseCodeAlign() const {
103 return getKind().isText();
104 }
105
isVirtualSection() const106 bool MCSectionCOFF::isVirtualSection() const {
107 return getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
108 }
109