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/COFF.h"
15 #include "llvm/Support/raw_ostream.h"
16 using namespace llvm;
17
~MCSectionCOFF()18 MCSectionCOFF::~MCSectionCOFF() {} // anchor.
19
20 // ShouldOmitSectionDirective - Decides whether a '.section' directive
21 // should be printed before the section name
ShouldOmitSectionDirective(StringRef Name,const MCAsmInfo & MAI) const22 bool MCSectionCOFF::ShouldOmitSectionDirective(StringRef Name,
23 const MCAsmInfo &MAI) const {
24 if (COMDATSymbol)
25 return false;
26
27 // FIXME: Does .section .bss/.data/.text work everywhere??
28 if (Name == ".text" || Name == ".data" || Name == ".bss")
29 return true;
30
31 return false;
32 }
33
setSelection(int Selection) const34 void MCSectionCOFF::setSelection(int Selection) const {
35 assert(Selection != 0 && "invalid COMDAT selection type");
36 this->Selection = Selection;
37 Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
38 }
39
PrintSwitchToSection(const MCAsmInfo & MAI,raw_ostream & OS,const MCExpr * Subsection) const40 void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI,
41 raw_ostream &OS,
42 const MCExpr *Subsection) const {
43
44 // standard sections don't require the '.section'
45 if (ShouldOmitSectionDirective(SectionName, MAI)) {
46 OS << '\t' << getSectionName() << '\n';
47 return;
48 }
49
50 OS << "\t.section\t" << getSectionName() << ",\"";
51 if (getCharacteristics() & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
52 OS << 'd';
53 if (getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
54 OS << 'b';
55 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_EXECUTE)
56 OS << 'x';
57 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_WRITE)
58 OS << 'w';
59 else if (getCharacteristics() & COFF::IMAGE_SCN_MEM_READ)
60 OS << 'r';
61 else
62 OS << 'y';
63 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_REMOVE)
64 OS << 'n';
65 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_SHARED)
66 OS << 's';
67 OS << '"';
68
69 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_COMDAT) {
70 OS << ",";
71 switch (Selection) {
72 case COFF::IMAGE_COMDAT_SELECT_NODUPLICATES:
73 OS << "one_only,";
74 break;
75 case COFF::IMAGE_COMDAT_SELECT_ANY:
76 OS << "discard,";
77 break;
78 case COFF::IMAGE_COMDAT_SELECT_SAME_SIZE:
79 OS << "same_size,";
80 break;
81 case COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH:
82 OS << "same_contents,";
83 break;
84 case COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE:
85 OS << "associative,";
86 break;
87 case COFF::IMAGE_COMDAT_SELECT_LARGEST:
88 OS << "largest,";
89 break;
90 case COFF::IMAGE_COMDAT_SELECT_NEWEST:
91 OS << "newest,";
92 break;
93 default:
94 assert (0 && "unsupported COFF selection type");
95 break;
96 }
97 assert(COMDATSymbol);
98 COMDATSymbol->print(OS, &MAI);
99 }
100 OS << '\n';
101 }
102
UseCodeAlign() const103 bool MCSectionCOFF::UseCodeAlign() const {
104 return getKind().isText();
105 }
106
isVirtualSection() const107 bool MCSectionCOFF::isVirtualSection() const {
108 return getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
109 }
110