//
//===----------------------------------------------------------------------===//
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/GlobalVariable.h"
-#include "llvm/Function.h"
-#include "llvm/Module.h"
-#include "llvm/Type.h"
#include "llvm/Target/TargetAsmInfo.h"
-#include "llvm/Target/TargetData.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetOptions.h"
-#include "llvm/Support/Dwarf.h"
-#include "llvm/Support/ErrorHandling.h"
#include <cctype>
#include <cstring>
using namespace llvm;
-TargetAsmInfo::TargetAsmInfo(const TargetMachine &tm) : TM(tm) {
- BSSSection = "\t.bss";
- BSSSection_ = 0;
- ReadOnlySection = 0;
- TLSDataSection = 0;
- TLSBSSSection = 0;
+TargetAsmInfo::TargetAsmInfo() {
ZeroFillDirective = 0;
NonexecutableStackDirective = 0;
NeedsSet = false;
TextSectionStartSuffix = "";
DataSectionStartSuffix = "";
SectionEndDirectiveSuffix = 0;
- ConstantPoolSection = "\t.section .rodata";
- JumpTableDataSection = "\t.section .rodata";
JumpTableDirective = 0;
- CStringSection = 0;
- CStringSection_ = 0;
- // FIXME: Flags are ELFish - replace with normal section stuff.
- StaticCtorsSection = "\t.section .ctors,\"aw\",@progbits";
- StaticDtorsSection = "\t.section .dtors,\"aw\",@progbits";
GlobalDirective = "\t.globl\t";
SetDirective = 0;
LCOMMDirective = 0;
GlobalEHDirective = 0;
SupportsWeakOmittedEHFrame = true;
DwarfSectionOffsetDirective = 0;
- DwarfAbbrevSection = ".debug_abbrev";
- DwarfInfoSection = ".debug_info";
- DwarfLineSection = ".debug_line";
- DwarfFrameSection = ".debug_frame";
- DwarfPubNamesSection = ".debug_pubnames";
- DwarfPubTypesSection = ".debug_pubtypes";
- DwarfDebugInlineSection = ".debug_inlined";
- DwarfStrSection = ".debug_str";
- DwarfLocSection = ".debug_loc";
- DwarfARangesSection = ".debug_aranges";
- DwarfRangesSection = ".debug_ranges";
- DwarfMacroInfoSection = ".debug_macinfo";
- DwarfEHFrameSection = ".eh_frame";
- DwarfExceptionSection = ".gcc_except_table";
+
AsmTransCBE = 0;
- TextSection = getUnnamedSection("\t.text", SectionFlags::Code);
- DataSection = getUnnamedSection("\t.data", SectionFlags::Writable);
}
TargetAsmInfo::~TargetAsmInfo() {
}
-/// Measure the specified inline asm to determine an approximation of its
-/// length.
-/// Comments (which run till the next SeparatorChar or newline) do not
-/// count as an instruction.
-/// Any other non-whitespace text is considered an instruction, with
-/// multiple instructions separated by SeparatorChar or newlines.
-/// Variable-length instructions are not handled here; this function
-/// may be overloaded in the target code to do that.
-unsigned TargetAsmInfo::getInlineAsmLength(const char *Str) const {
- // Count the number of instructions in the asm.
- bool atInsnStart = true;
- unsigned Length = 0;
- for (; *Str; ++Str) {
- if (*Str == '\n' || *Str == SeparatorChar)
- atInsnStart = true;
- if (atInsnStart && !isspace(*Str)) {
- Length += MaxInstLength;
- atInsnStart = false;
- }
- if (atInsnStart && strncmp(Str, CommentString, strlen(CommentString))==0)
- atInsnStart = false;
- }
-
- return Length;
-}
-
-unsigned TargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
- bool Global) const {
- return dwarf::DW_EH_PE_absptr;
-}
-
-static bool isSuitableForBSS(const GlobalVariable *GV) {
- Constant *C = GV->getInitializer();
-
- // Must have zero initializer.
- if (!C->isNullValue())
- return false;
-
- // Leave constant zeros in readonly constant sections, so they can be shared.
- if (GV->isConstant())
- return false;
-
- // If the global has an explicit section specified, don't put it in BSS.
- if (!GV->getSection().empty())
- return false;
-
- // If -nozero-initialized-in-bss is specified, don't ever use BSS.
- if (NoZerosInBSS)
- return false;
-
- // Otherwise, put it in BSS!
- return true;
-}
-
-static bool isConstantString(const Constant *C) {
- // First check: is we have constant array of i8 terminated with zero
- const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
- // Check, if initializer is a null-terminated string
- if (CVA && CVA->isCString())
- return true;
-
- // Another possibility: [1 x i8] zeroinitializer
- if (isa<ConstantAggregateZero>(C))
- if (const ArrayType *Ty = dyn_cast<ArrayType>(C->getType()))
- return (Ty->getElementType() == Type::Int8Ty &&
- Ty->getNumElements() == 1);
-
- return false;
-}
-
-static unsigned SectionFlagsForGlobal(const GlobalValue *GV,
- SectionKind Kind) {
- // Decode flags from global and section kind.
- unsigned Flags = SectionFlags::None;
- if (GV->isWeakForLinker())
- Flags |= SectionFlags::Linkonce;
- if (Kind.isBSS() || Kind.isThreadBSS())
- Flags |= SectionFlags::BSS;
- if (Kind.isThreadLocal())
- Flags |= SectionFlags::TLS;
- if (Kind.isText())
- Flags |= SectionFlags::Code;
- if (Kind.isWritable())
- Flags |= SectionFlags::Writable;
-
- return Flags;
-}
-
-static SectionKind SectionKindForGlobal(const GlobalValue *GV,
- const TargetMachine &TM) {
- Reloc::Model ReloModel = TM.getRelocationModel();
-
- // Early exit - functions should be always in text sections.
- const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
- if (GVar == 0)
- return SectionKind::getText();
-
- bool isThreadLocal = GVar->isThreadLocal();
-
- // Variable can be easily put to BSS section.
- if (isSuitableForBSS(GVar))
- return isThreadLocal ? SectionKind::getThreadBSS() : SectionKind::getBSS();
-
- // If this is thread-local, put it in the general "thread_data" section.
- if (isThreadLocal)
- return SectionKind::getThreadData();
-
- Constant *C = GVar->getInitializer();
-
- // If the global is marked constant, we can put it into a mergable section,
- // a mergable string section, or general .data if it contains relocations.
- if (GVar->isConstant()) {
- // If the initializer for the global contains something that requires a
- // relocation, then we may have to drop this into a wriable data section
- // even though it is marked const.
- switch (C->getRelocationInfo()) {
- default: llvm_unreachable("unknown relocation info kind");
- case Constant::NoRelocation:
- // If initializer is a null-terminated string, put it in a "cstring"
- // section if the target has it.
- if (isConstantString(C))
- return SectionKind::getMergableCString();
-
- // Otherwise, just drop it into a mergable constant section. If we have
- // a section for this size, use it, otherwise use the arbitrary sized
- // mergable section.
- switch (TM.getTargetData()->getTypeAllocSize(C->getType())) {
- case 4: return SectionKind::getMergableConst4();
- case 8: return SectionKind::getMergableConst8();
- case 16: return SectionKind::getMergableConst16();
- default: return SectionKind::getMergableConst();
- }
-
- case Constant::LocalRelocation:
- // In static relocation model, the linker will resolve all addresses, so
- // the relocation entries will actually be constants by the time the app
- // starts up.
- if (ReloModel == Reloc::Static)
- return SectionKind::getReadOnly();
-
- // Otherwise, the dynamic linker needs to fix it up, put it in the
- // writable data.rel.local section.
- return SectionKind::getReadOnlyWithRelLocal();
-
- case Constant::GlobalRelocations:
- // In static relocation model, the linker will resolve all addresses, so
- // the relocation entries will actually be constants by the time the app
- // starts up.
- if (ReloModel == Reloc::Static)
- return SectionKind::getReadOnly();
-
- // Otherwise, the dynamic linker needs to fix it up, put it in the
- // writable data.rel section.
- return SectionKind::getReadOnlyWithRel();
- }
- }
-
- // Okay, this isn't a constant. If the initializer for the global is going
- // to require a runtime relocation by the dynamic linker, put it into a more
- // specific section to improve startup time of the app. This coalesces these
- // globals together onto fewer pages, improving the locality of the dynamic
- // linker.
- if (ReloModel == Reloc::Static)
- return SectionKind::getDataNoRel();
-
- switch (C->getRelocationInfo()) {
- default: llvm_unreachable("unknown relocation info kind");
- case Constant::NoRelocation: return SectionKind::getDataNoRel();
- case Constant::LocalRelocation: return SectionKind::getDataRelLocal();
- case Constant::GlobalRelocations: return SectionKind::getDataRel();
- }
-}
-
-/// SectionForGlobal - This method computes the appropriate section to emit
-/// the specified global variable or function definition. This should not
-/// be passed external (or available externally) globals.
-const Section *TargetAsmInfo::SectionForGlobal(const GlobalValue *GV) const {
- assert(!GV->isDeclaration() && !GV->hasAvailableExternallyLinkage() &&
- "Can only be used for global definitions");
-
- SectionKind Kind = SectionKindForGlobal(GV, TM);
-
- // Select section name.
- if (GV->hasSection()) {
- // If the target has special section hacks for specifically named globals,
- // return them now.
- if (const Section *TS = getSpecialCasedSectionGlobals(GV, Kind))
- return TS;
-
- // Honour section already set, if any.
- unsigned Flags = SectionFlagsForGlobal(GV, Kind);
-
- // This is an explicitly named section.
- Flags |= SectionFlags::Named;
-
- // If the target has magic semantics for certain section names, make sure to
- // pick up the flags. This allows the user to write things with attribute
- // section and still get the appropriate section flags printed.
- Flags |= getFlagsForNamedSection(GV->getSection().c_str());
-
- return getNamedSection(GV->getSection().c_str(), Flags);
- }
-
- // If this global is linkonce/weak and the target handles this by emitting it
- // into a 'uniqued' section name, create and return the section now.
- if (GV->isWeakForLinker()) {
- if (const char *Prefix = getSectionPrefixForUniqueGlobal(Kind)) {
- unsigned Flags = SectionFlagsForGlobal(GV, Kind);
-
- // FIXME: Use mangler interface (PR4584).
- std::string Name = Prefix+GV->getNameStr();
- return getNamedSection(Name.c_str(), Flags);
- }
- }
-
- // Use default section depending on the 'type' of global
- return SelectSectionForGlobal(GV, Kind);
-}
-
-// Lame default implementation. Calculate the section name for global.
-const Section*
-TargetAsmInfo::SelectSectionForGlobal(const GlobalValue *GV,
- SectionKind Kind) const {
- assert(!Kind.isThreadLocal() && "Doesn't support TLS");
-
- if (Kind.isText())
- return getTextSection();
-
- if (Kind.isBSS())
- if (const Section *S = getBSSSection_())
- return S;
-
- if (Kind.isReadOnly())
- if (const Section *S = getReadOnlySection())
- return S;
-
- return getDataSection();
-}
-
-/// getSectionForMergableConstant - Given a mergable constant with the
-/// specified size and relocation information, return a section that it
-/// should be placed in.
-const Section *
-TargetAsmInfo::getSectionForMergableConstant(SectionKind Kind) const {
- if (Kind.isReadOnly())
- if (const Section *S = getReadOnlySection())
- return S;
-
- return getDataSection();
-}
-
-
-const Section *TargetAsmInfo::getNamedSection(const char *Name, unsigned Flags,
- bool Override) const {
- Section &S = Sections[Name];
-
- // This is newly-created section, set it up properly.
- if (S.Flags == SectionFlags::Invalid || Override) {
- S.Flags = Flags | SectionFlags::Named;
- S.Name = Name;
- }
-
- return &S;
-}
-
-const Section*
-TargetAsmInfo::getUnnamedSection(const char *Directive, unsigned Flags,
- bool Override) const {
- Section& S = Sections[Directive];
-
- // This is newly-created section, set it up properly.
- if (S.Flags == SectionFlags::Invalid || Override) {
- S.Flags = Flags & ~SectionFlags::Named;
- S.Name = Directive;
- }
-
- return &S;
-}
-
-const std::string&
-TargetAsmInfo::getSectionFlags(unsigned Flags) const {
- SectionFlags::FlagsStringsMapType::iterator I = FlagsStrings.find(Flags);
-
- // We didn't print these flags yet, print and save them to map. This reduces
- // amount of heap trashing due to std::string construction / concatenation.
- if (I == FlagsStrings.end())
- I = FlagsStrings.insert(std::make_pair(Flags,
- printSectionFlags(Flags))).first;
-
- return I->second;
-}
unsigned TargetAsmInfo::getULEB128Size(unsigned Value) {
unsigned Size = 0;
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