1 //===-- DarwinTargetAsmInfo.cpp - Darwin asm properties ---------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines target asm properties related what form asm statements
11 // should take in general on Darwin-based targets
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Constants.h"
16 #include "llvm/DerivedTypes.h"
17 #include "llvm/Function.h"
18 #include "llvm/GlobalVariable.h"
19 #include "llvm/ADT/StringExtras.h"
20 #include "llvm/Support/Mangler.h"
21 #include "llvm/Target/DarwinTargetAsmInfo.h"
22 #include "llvm/Target/TargetMachine.h"
23 #include "llvm/Target/TargetData.h"
27 DarwinTargetAsmInfo::DarwinTargetAsmInfo(const TargetMachine &TM)
30 CStringSection_ = getUnnamedSection("\t.cstring",
31 SectionFlags::Mergeable | SectionFlags::Strings);
32 FourByteConstantSection = getUnnamedSection("\t.literal4\n",
33 SectionFlags::Mergeable);
34 EightByteConstantSection = getUnnamedSection("\t.literal8\n",
35 SectionFlags::Mergeable);
37 // Note: 16-byte constant section is subtarget specific and should be provided
39 SixteenByteConstantSection = 0;
41 ReadOnlySection = getUnnamedSection("\t.const\n", SectionFlags::None);
44 getNamedSection("\t__TEXT,__textcoal_nt,coalesced,pure_instructions",
46 ConstTextCoalSection = getNamedSection("\t__TEXT,__const_coal,coalesced",
48 ConstDataCoalSection = getNamedSection("\t__DATA,__const_coal,coalesced",
50 ConstDataSection = getUnnamedSection(".const_data", SectionFlags::None);
51 DataCoalSection = getNamedSection("\t__DATA,__datacoal_nt,coalesced",
52 SectionFlags::Writeable);
55 /// emitUsedDirectiveFor - On Darwin, internally linked data beginning with
56 /// the PrivateGlobalPrefix or the LessPrivateGlobalPrefix does not have the
57 /// directive emitted (this occurs in ObjC metadata).
60 DarwinTargetAsmInfo::emitUsedDirectiveFor(const GlobalValue* GV,
61 Mangler *Mang) const {
64 if (GV->hasLocalLinkage() && !isa<Function>(GV) &&
65 ((strlen(getPrivateGlobalPrefix()) != 0 &&
66 Mang->getValueName(GV).substr(0,strlen(getPrivateGlobalPrefix())) ==
67 getPrivateGlobalPrefix()) ||
68 (strlen(getLessPrivateGlobalPrefix()) != 0 &&
69 Mang->getValueName(GV).substr(0,strlen(getLessPrivateGlobalPrefix())) ==
70 getLessPrivateGlobalPrefix())))
76 DarwinTargetAsmInfo::SelectSectionForGlobal(const GlobalValue *GV) const {
77 SectionKind::Kind Kind = SectionKindForGlobal(GV);
78 bool isWeak = GV->isWeakForLinker();
79 bool isNonStatic = TM.getRelocationModel() != Reloc::Static;
82 case SectionKind::Text:
84 return TextCoalSection;
87 case SectionKind::Data:
88 case SectionKind::DataRel:
89 case SectionKind::DataRelRO:
90 case SectionKind::DataRelROLocal:
91 case SectionKind::ThreadData:
92 case SectionKind::BSS:
93 case SectionKind::ThreadBSS:
94 if (cast<GlobalVariable>(GV)->isConstant())
95 return (isWeak ? ConstDataCoalSection : ConstDataSection);
97 return (isWeak ? DataCoalSection : DataSection);
98 case SectionKind::ROData:
99 return (isWeak ? ConstDataCoalSection :
100 (isNonStatic ? ConstDataSection : getReadOnlySection()));
101 case SectionKind::RODataMergeStr:
103 ConstTextCoalSection :
104 MergeableStringSection(cast<GlobalVariable>(GV)));
105 case SectionKind::RODataMergeConst:
107 ConstDataCoalSection:
108 MergeableConstSection(cast<GlobalVariable>(GV)));
110 assert(0 && "Unsuported section kind for global");
113 // FIXME: Do we have any extra special weird cases?
118 DarwinTargetAsmInfo::MergeableStringSection(const GlobalVariable *GV) const {
119 const TargetData *TD = TM.getTargetData();
120 Constant *C = cast<GlobalVariable>(GV)->getInitializer();
121 const Type *Ty = cast<ArrayType>(C->getType())->getElementType();
123 unsigned Size = TD->getTypePaddedSize(Ty);
125 unsigned Align = TD->getPreferredAlignment(GV);
127 return getCStringSection_();
130 return getReadOnlySection();
134 DarwinTargetAsmInfo::MergeableConstSection(const GlobalVariable *GV) const {
135 Constant *C = GV->getInitializer();
137 return MergeableConstSection(C->getType());
140 inline const Section*
141 DarwinTargetAsmInfo::MergeableConstSection(const Type *Ty) const {
142 const TargetData *TD = TM.getTargetData();
144 unsigned Size = TD->getTypePaddedSize(Ty);
146 return FourByteConstantSection;
148 return EightByteConstantSection;
149 else if (Size == 16 && SixteenByteConstantSection)
150 return SixteenByteConstantSection;
152 return getReadOnlySection();
156 DarwinTargetAsmInfo::SelectSectionForMachineConst(const Type *Ty) const {
157 const Section* S = MergeableConstSection(Ty);
159 // Handle weird special case, when compiling PIC stuff.
160 if (S == getReadOnlySection() &&
161 TM.getRelocationModel() != Reloc::Static)
162 return ConstDataSection;
168 DarwinTargetAsmInfo::UniqueSectionForGlobal(const GlobalValue* GV,
169 SectionKind::Kind kind) const {
170 assert(0 && "Darwin does not use unique sections");