Cleanup handling of .zerofill on darwin:

1. TargetLoweringObjectFileMachO should decide if something
   goes in zerofill instead of having every target do it.
2. TargetLoweringObjectFileMachO should assign said symbols to
   the right MCSection, the asmprinters should just emit to the
   right section.
3. Since all zerofill stuff goes through mcstreamer anymore,
   MAI can have a bool "haszerofill" instead of having the textual
   directive to emit.

llvm-svn: 93838
This commit is contained in:
Chris Lattner 2010-01-19 02:09:44 +00:00
parent 5e1a83c196
commit 1d371882b6
8 changed files with 175 additions and 152 deletions

View File

@ -29,15 +29,15 @@ namespace llvm {
// Properties to be set by the target writer, used to configure asm printer.
//
/// ZeroFillDirective - Directive for emitting a global to the ZeroFill
/// section on this target. Null if this target doesn't support zerofill.
const char *ZeroFillDirective; // Default is null.
/// NonexecutableStackDirective - Directive for declaring to the
/// linker and beyond that the emitted code does not require stack
/// memory to be executable.
const char *NonexecutableStackDirective; // Default is null.
/// HasMachoZeroFillDirective - True if this is a MachO target that supports
/// the macho-specific .zerofill directive for emitting BSS Symbols.
bool HasMachoZeroFillDirective; // Default is false.
/// NeedsSet - True if target asm treats expressions in data directives
/// as linktime-relocatable. For assembly-time computation, we need to
/// use a .set. Thus:
@ -313,10 +313,7 @@ namespace llvm {
// Accessors.
//
const char *getZeroFillDirective() const {
return ZeroFillDirective;
}
bool hasZeroFillDirective() const { return ZeroFillDirective != 0; }
bool hasMachoZeroFillDirective() const { return HasMachoZeroFillDirective; }
const char *getNonexecutableStackDirective() const {
return NonexecutableStackDirective;

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@ -258,6 +258,7 @@ class TargetLoweringObjectFileMachO : public TargetLoweringObjectFile {
const MCSection *ConstDataCoalSection;
const MCSection *ConstDataSection;
const MCSection *DataCoalSection;
const MCSection *DataCommonSection;
const MCSection *FourByteConstantSection;
const MCSection *EightByteConstantSection;
const MCSection *SixteenByteConstantSection;
@ -312,6 +313,12 @@ public:
return ConstTextCoalSection;
}
/// getDataCommonSection - Return the "__DATA,__common" section we put
/// zerofill (aka bss) data into.
const MCSection *getDataCommonSection() const {
return DataCommonSection;
}
/// getLazySymbolPointerSection - Return the section corresponding to
/// the .lazy_symbol_pointer directive.
const MCSection *getLazySymbolPointerSection() const {

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@ -19,7 +19,7 @@
using namespace llvm;
MCAsmInfo::MCAsmInfo() {
ZeroFillDirective = 0;
HasMachoZeroFillDirective = false;
NonexecutableStackDirective = 0;
NeedsSet = false;
MaxInstLength = 4;

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@ -35,7 +35,7 @@ MCAsmInfoDarwin::MCAsmInfoDarwin() {
HiddenDirective = "\t.private_extern ";
LCOMMDirective = "\t.lcomm\t";
ZeroDirective = "\t.space\t"; // ".space N" emits N zeros.
ZeroFillDirective = "\t.zerofill\t"; // Uses .zerofill
HasMachoZeroFillDirective = true; // Uses .zerofill
SetDirective = "\t.set";
ProtectedDirective = "\t.globl\t";
HasDotTypeDotSizeDirective = false;

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@ -1196,71 +1196,76 @@ void ARMAsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
if (Subtarget->isTargetELF())
O << "\t.type " << *GVarSym << ",%object\n";
SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GVar, TM);
const MCSection *TheSection =
getObjFileLowering().SectionForGlobal(GVar, Mang, TM);
getObjFileLowering().SectionForGlobal(GVar, GVKind, Mang, TM);
OutStreamer.SwitchSection(TheSection);
// Handle the zerofill directive on darwin, which is a special form of BSS
// emission.
if (GVKind.isBSS() && MAI->hasMachoZeroFillDirective()) {
TargetLoweringObjectFileMachO &TLOFMacho =
static_cast<TargetLoweringObjectFileMachO &>(getObjFileLowering());
if (TheSection == TLOFMacho.getDataCommonSection()) {
// .globl _foo
OutStreamer.EmitSymbolAttribute(GVarSym, MCStreamer::Global);
// .zerofill __DATA, __common, _foo, 400, 5
OutStreamer.EmitZerofill(TheSection, GVarSym, Size, 1 << Align);
return;
}
}
// FIXME: get this stuff from section kind flags.
if (C->isNullValue() && !GVar->hasSection() && !GVar->isThreadLocal() &&
// Don't put things that should go in the cstring section into "comm".
!TheSection->getKind().isMergeableCString()) {
if (GVar->hasExternalLinkage()) {
if (const char *Directive = MAI->getZeroFillDirective()) {
O << "\t.globl\t" << *GVarSym << "\n";
O << Directive << "__DATA, __common, " << *GVarSym
<< ", " << Size << ", " << Align << "\n";
!TheSection->getKind().isMergeableCString() &&
(GVar->hasLocalLinkage() || GVar->isWeakForLinker())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (isDarwin) {
if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVarSym << ',' << Size
<< ',' << Align;
} else if (GVar->hasCommonLinkage()) {
O << MAI->getCOMMDirective() << *GVarSym << ',' << Size
<< ',' << Align;
} else {
OutStreamer.SwitchSection(TheSection);
O << "\t.globl " << *GVarSym << '\n' << MAI->getWeakDefDirective();
O << *GVarSym << '\n';
EmitAlignment(Align, GVar);
O << *GVarSym << ":";
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
}
O << '\n';
EmitGlobalConstant(C);
return;
}
}
if (GVar->hasLocalLinkage() || GVar->isWeakForLinker()) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (isDarwin) {
if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVarSym << ',' << Size
<< ',' << Align;
} else if (GVar->hasCommonLinkage()) {
O << MAI->getCOMMDirective() << *GVarSym << ',' << Size
<< ',' << Align;
} else {
OutStreamer.SwitchSection(TheSection);
O << "\t.globl " << *GVarSym << '\n' << MAI->getWeakDefDirective();
O << *GVarSym << '\n';
EmitAlignment(Align, GVar);
O << *GVarSym << ":";
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
}
O << '\n';
EmitGlobalConstant(C);
return;
}
} else if (MAI->getLCOMMDirective() != NULL) {
if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVarSym << "," << Size;
} else {
O << MAI->getCOMMDirective() << *GVarSym << "," << Size;
if (MAI->getCOMMDirectiveTakesAlignment())
O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
}
} else if (MAI->getLCOMMDirective() != NULL) {
if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVarSym << "," << Size;
} else {
if (GVar->hasLocalLinkage())
O << "\t.local\t" << *GVarSym << '\n';
O << MAI->getCOMMDirective() << *GVarSym << "," << Size;
if (MAI->getCOMMDirectiveTakesAlignment())
O << "," << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
}
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
}
O << "\n";
return;
} else {
if (GVar->hasLocalLinkage())
O << "\t.local\t" << *GVarSym << '\n';
O << MAI->getCOMMDirective() << *GVarSym << "," << Size;
if (MAI->getCOMMDirectiveTakesAlignment())
O << "," << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
}
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
}
O << "\n";
return;
}
switch (GVar->getLinkage()) {

View File

@ -721,25 +721,25 @@ void PPCLinuxAsmPrinter::PrintGlobalVariable(const GlobalVariable *GVar) {
!GVar->hasSection() &&
(GVar->hasLocalLinkage() || GVar->hasExternalLinkage() ||
GVar->isWeakForLinker())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (GVar->hasExternalLinkage()) {
O << "\t.global " << *GVarSym << '\n';
O << "\t.type " << *GVarSym << ", @object\n";
O << *GVarSym << ":\n";
O << "\t.zero " << Size << '\n';
} else if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVarSym << ',' << Size;
} else {
O << ".comm " << *GVarSym << ',' << Size;
}
if (VerboseAsm) {
O << "\t\t" << MAI->getCommentString() << " '";
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
O << "'";
}
O << '\n';
return;
if (GVar->hasExternalLinkage()) {
O << "\t.global " << *GVarSym << '\n';
O << "\t.type " << *GVarSym << ", @object\n";
O << *GVarSym << ":\n";
O << "\t.zero " << Size << '\n';
} else if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVarSym << ',' << Size;
} else {
O << ".comm " << *GVarSym << ',' << Size;
}
if (VerboseAsm) {
O << "\t\t" << MAI->getCommentString() << " '";
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
O << "'";
}
O << '\n';
return;
}
switch (GVar->getLinkage()) {
@ -944,10 +944,25 @@ void PPCDarwinAsmPrinter::PrintGlobalVariable(const GlobalVariable *GVar) {
unsigned Size = TD->getTypeAllocSize(Type);
unsigned Align = TD->getPreferredAlignmentLog(GVar);
SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GVar, TM);
const MCSection *TheSection =
getObjFileLowering().SectionForGlobal(GVar, Mang, TM);
getObjFileLowering().SectionForGlobal(GVar, GVKind, Mang, TM);
OutStreamer.SwitchSection(TheSection);
// Handle the zerofill directive on darwin, which is a special form of BSS
// emission.
if (GVKind.isBSS() && MAI->hasMachoZeroFillDirective()) {
TargetLoweringObjectFileMachO &TLOFMacho =
static_cast<TargetLoweringObjectFileMachO &>(getObjFileLowering());
if (TheSection == TLOFMacho.getDataCommonSection()) {
// .globl _foo
OutStreamer.EmitSymbolAttribute(GVarSym, MCStreamer::Global);
// .zerofill __DATA, __common, _foo, 400, 5
OutStreamer.EmitZerofill(TheSection, GVarSym, Size, 1 << Align);
return;
}
}
/// FIXME: Drive this off the section!
if (C->isNullValue() && /* FIXME: Verify correct */
!GVar->hasSection() &&
@ -957,11 +972,7 @@ void PPCDarwinAsmPrinter::PrintGlobalVariable(const GlobalVariable *GVar) {
!TheSection->getKind().isMergeableCString()) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (GVar->hasExternalLinkage()) {
O << "\t.globl " << *GVarSym << '\n';
O << "\t.zerofill __DATA, __common, " << *GVarSym << ", "
<< Size << ", " << Align;
} else if (GVar->hasLocalLinkage()) {
if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVarSym << ',' << Size << ',' << Align;
} else if (!GVar->hasCommonLinkage()) {
O << "\t.globl " << *GVarSym << '\n' << MAI->getWeakDefDirective();

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@ -750,6 +750,9 @@ void TargetLoweringObjectFileMachO::Initialize(MCContext &Ctx,
ConstDataCoalSection
= getMachOSection("__DATA","__const_coal", MCSectionMachO::S_COALESCED,
SectionKind::getText());
DataCommonSection
= getMachOSection("__DATA","__common", MCSectionMachO::S_ZEROFILL,
SectionKind::getBSS());
ConstDataSection // .const_data
= getMachOSection("__DATA", "__const", 0,
SectionKind::getReadOnlyWithRel());
@ -915,6 +918,11 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
if (Kind.isReadOnlyWithRel())
return ConstDataSection;
// Put zero initialized globals with strong external linkage in the
// DATA, __common section with the .zerofill directive.
if (Kind.isBSS() && GV->hasExternalLinkage())
return DataCommonSection;
// Otherwise, just drop the variable in the normal data section.
return DataSection;
}

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@ -664,88 +664,83 @@ void X86AsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
const TargetData *TD = TM.getTargetData();
MCSymbol *GVSym = GetGlobalValueSymbol(GVar);
MCSymbol *GVarSym = GetGlobalValueSymbol(GVar);
Constant *C = GVar->getInitializer();
const Type *Type = C->getType();
unsigned Size = TD->getTypeAllocSize(Type);
unsigned Align = TD->getPreferredAlignmentLog(GVar);
printVisibility(GVSym, GVar->getVisibility());
printVisibility(GVarSym, GVar->getVisibility());
if (Subtarget->isTargetELF())
O << "\t.type\t" << *GVSym << ",@object\n";
O << "\t.type\t" << *GVarSym << ",@object\n";
SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GVar, TM);
const MCSection *TheSection =
getObjFileLowering().SectionForGlobal(GVar, GVKind, Mang, TM);
OutStreamer.SwitchSection(TheSection);
// Handle the zerofill directive on darwin, which is a special form of BSS
// emission.
if (GVKind.isBSS() && MAI->hasMachoZeroFillDirective()) {
TargetLoweringObjectFileMachO &TLOFMacho =
static_cast<TargetLoweringObjectFileMachO &>(getObjFileLowering());
if (TheSection == TLOFMacho.getDataCommonSection()) {
// .globl _foo
OutStreamer.EmitSymbolAttribute(GVarSym, MCStreamer::Global);
// .zerofill __DATA, __common, _foo, 400, 5
OutStreamer.EmitZerofill(TheSection, GVarSym, Size, 1 << Align);
return;
}
}
// FIXME: get this stuff from section kind flags.
if (C->isNullValue() && !GVar->hasSection() &&
// Don't put things that should go in the cstring section into "comm".
!TheSection->getKind().isMergeableCString()) {
if (GVar->hasExternalLinkage()) {
if (MAI->hasZeroFillDirective()) {
// .globl _foo
OutStreamer.EmitSymbolAttribute(GVSym, MCStreamer::Global);
// .zerofill __DATA, __common, _foo, 400, 5
TargetLoweringObjectFileMachO &TLOFMacho =
static_cast<TargetLoweringObjectFileMachO &>(getObjFileLowering());
// FIXME: This stuff should already be handled by SectionForGlobal!
const MCSection *TheSection =
TLOFMacho.getMachOSection("__DATA", "__common",
MCSectionMachO::S_ZEROFILL,
SectionKind::getBSS());
OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << Align);
!TheSection->getKind().isMergeableCString() &&
!GVar->isThreadLocal() &&
(GVar->hasLocalLinkage() || GVar->isWeakForLinker())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (const char *LComm = MAI->getLCOMMDirective()) {
if (GVar->hasLocalLinkage()) {
O << LComm << *GVarSym << ',' << Size;
if (Subtarget->isTargetDarwin())
O << ',' << Align;
} else if (Subtarget->isTargetDarwin() && !GVar->hasCommonLinkage()) {
OutStreamer.EmitSymbolAttribute(GVarSym, MCStreamer::Global);
O << MAI->getWeakDefDirective() << *GVarSym << '\n';
EmitAlignment(Align, GVar);
O << *GVarSym << ":";
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
}
O << '\n';
EmitGlobalConstant(C);
return;
}
}
if (!GVar->isThreadLocal() &&
(GVar->hasLocalLinkage() || GVar->isWeakForLinker())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (MAI->getLCOMMDirective() != NULL) {
if (GVar->hasLocalLinkage()) {
O << MAI->getLCOMMDirective() << *GVSym << ',' << Size;
if (Subtarget->isTargetDarwin())
O << ',' << Align;
} else if (Subtarget->isTargetDarwin() && !GVar->hasCommonLinkage()) {
OutStreamer.EmitSymbolAttribute(GVSym, MCStreamer::Global);
O << MAI->getWeakDefDirective() << *GVSym << '\n';
EmitAlignment(Align, GVar);
O << *GVSym << ":";
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
}
O << '\n';
EmitGlobalConstant(C);
return;
} else {
O << MAI->getCOMMDirective() << *GVSym << ',' << Size;
if (MAI->getCOMMDirectiveTakesAlignment())
O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
}
} else {
if (!Subtarget->isTargetCygMing()) {
if (GVar->hasLocalLinkage())
O << "\t.local\t" << *GVSym << '\n';
}
O << MAI->getCOMMDirective() << *GVSym << ',' << Size;
O << MAI->getCOMMDirective() << *GVarSym << ',' << Size;
if (MAI->getCOMMDirectiveTakesAlignment())
O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
}
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
} else {
if (!Subtarget->isTargetCygMing()) {
if (GVar->hasLocalLinkage())
O << "\t.local\t" << *GVarSym << '\n';
}
O << '\n';
return;
O << MAI->getCOMMDirective() << *GVarSym << ',' << Size;
if (MAI->getCOMMDirectiveTakesAlignment())
O << ',' << (MAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
}
if (VerboseAsm) {
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
WriteAsOperand(O, GVar, /*PrintType=*/false, GVar->getParent());
}
O << '\n';
return;
}
switch (GVar->getLinkage()) {
@ -756,13 +751,13 @@ void X86AsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
case GlobalValue::WeakODRLinkage:
case GlobalValue::LinkerPrivateLinkage:
if (Subtarget->isTargetDarwin()) {
OutStreamer.EmitSymbolAttribute(GVSym, MCStreamer::Global);
O << MAI->getWeakDefDirective() << *GVSym << '\n';
OutStreamer.EmitSymbolAttribute(GVarSym, MCStreamer::Global);
O << MAI->getWeakDefDirective() << *GVarSym << '\n';
} else if (Subtarget->isTargetCygMing()) {
OutStreamer.EmitSymbolAttribute(GVSym, MCStreamer::Global);
OutStreamer.EmitSymbolAttribute(GVarSym, MCStreamer::Global);
O << "\t.linkonce same_size\n";
} else
O << "\t.weak\t" << *GVSym << '\n';
O << "\t.weak\t" << *GVarSym << '\n';
break;
case GlobalValue::DLLExportLinkage:
case GlobalValue::AppendingLinkage:
@ -770,7 +765,7 @@ void X86AsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
// their name or something. For now, just emit them as external.
case GlobalValue::ExternalLinkage:
// If external or appending, declare as a global symbol
OutStreamer.EmitSymbolAttribute(GVSym, MCStreamer::Global);
OutStreamer.EmitSymbolAttribute(GVarSym, MCStreamer::Global);
break;
case GlobalValue::PrivateLinkage:
case GlobalValue::InternalLinkage:
@ -780,7 +775,7 @@ void X86AsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
}
EmitAlignment(Align, GVar);
O << *GVSym << ":";
O << *GVarSym << ":";
if (VerboseAsm){
O.PadToColumn(MAI->getCommentColumn());
O << MAI->getCommentString() << ' ';
@ -791,7 +786,7 @@ void X86AsmPrinter::PrintGlobalVariable(const GlobalVariable* GVar) {
EmitGlobalConstant(C);
if (MAI->hasDotTypeDotSizeDirective())
O << "\t.size\t" << *GVSym << ", " << Size << '\n';
O << "\t.size\t" << *GVarSym << ", " << Size << '\n';
}
void X86AsmPrinter::EmitEndOfAsmFile(Module &M) {