Revert r226242 - Revert Revert Don't create new comdats in CodeGen

This breaks AddressSanitizer (ninja check-asan) on Windows

llvm-svn: 226251
This commit is contained in:
Timur Iskhodzhanov 2015-01-16 08:38:45 +00:00
parent 24b04aa393
commit 60b721363c
15 changed files with 137 additions and 63 deletions

View File

@ -156,27 +156,19 @@ static bool ConvertToString(ArrayRef<uint64_t> Record, unsigned Idx,
return false;
}
static bool hasImplicitComdat(size_t Val) {
switch (Val) {
default:
return false;
case 1: // Old WeakAnyLinkage
case 4: // Old LinkOnceAnyLinkage
case 10: // Old WeakODRLinkage
case 11: // Old LinkOnceODRLinkage
return true;
}
}
static GlobalValue::LinkageTypes getDecodedLinkage(unsigned Val) {
switch (Val) {
default: // Map unknown/new linkages to external
case 0:
return GlobalValue::ExternalLinkage;
case 1:
return GlobalValue::WeakAnyLinkage;
case 2:
return GlobalValue::AppendingLinkage;
case 3:
return GlobalValue::InternalLinkage;
case 4:
return GlobalValue::LinkOnceAnyLinkage;
case 5:
return GlobalValue::ExternalLinkage; // Obsolete DLLImportLinkage
case 6:
@ -187,6 +179,10 @@ static GlobalValue::LinkageTypes getDecodedLinkage(unsigned Val) {
return GlobalValue::CommonLinkage;
case 9:
return GlobalValue::PrivateLinkage;
case 10:
return GlobalValue::WeakODRLinkage;
case 11:
return GlobalValue::LinkOnceODRLinkage;
case 12:
return GlobalValue::AvailableExternallyLinkage;
case 13:
@ -195,18 +191,6 @@ static GlobalValue::LinkageTypes getDecodedLinkage(unsigned Val) {
return GlobalValue::PrivateLinkage; // Obsolete LinkerPrivateWeakLinkage
case 15:
return GlobalValue::ExternalLinkage; // Obsolete LinkOnceODRAutoHideLinkage
case 1: // Old value with implicit comdat.
case 16:
return GlobalValue::WeakAnyLinkage;
case 10: // Old value with implicit comdat.
case 17:
return GlobalValue::WeakODRLinkage;
case 4: // Old value with implicit comdat.
case 18:
return GlobalValue::LinkOnceAnyLinkage;
case 11: // Old value with implicit comdat.
case 19:
return GlobalValue::LinkOnceODRLinkage;
}
}
@ -1134,10 +1118,6 @@ std::error_code BitcodeReader::ParseValueSymbolTable() {
Value *V = ValueList[ValueID];
V->setName(StringRef(ValueName.data(), ValueName.size()));
if (auto *GO = dyn_cast<GlobalObject>(V)) {
if (GO->getComdat() == reinterpret_cast<Comdat *>(1))
GO->setComdat(TheModule->getOrInsertComdat(V->getName()));
}
ValueName.clear();
break;
}
@ -2160,8 +2140,7 @@ std::error_code BitcodeReader::ParseModule(bool Resume) {
Ty = cast<PointerType>(Ty)->getElementType();
bool isConstant = Record[1];
uint64_t RawLinkage = Record[3];
GlobalValue::LinkageTypes Linkage = getDecodedLinkage(RawLinkage);
GlobalValue::LinkageTypes Linkage = getDecodedLinkage(Record[3]);
unsigned Alignment = (1 << Record[4]) >> 1;
std::string Section;
if (Record[5]) {
@ -2199,7 +2178,7 @@ std::error_code BitcodeReader::ParseModule(bool Resume) {
if (Record.size() > 10)
NewGV->setDLLStorageClass(GetDecodedDLLStorageClass(Record[10]));
else
UpgradeDLLImportExportLinkage(NewGV, RawLinkage);
UpgradeDLLImportExportLinkage(NewGV, Record[3]);
ValueList.push_back(NewGV);
@ -2207,14 +2186,11 @@ std::error_code BitcodeReader::ParseModule(bool Resume) {
if (unsigned InitID = Record[2])
GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
if (Record.size() > 11) {
if (Record.size() > 11)
if (unsigned ComdatID = Record[11]) {
assert(ComdatID <= ComdatList.size());
NewGV->setComdat(ComdatList[ComdatID - 1]);
}
} else if (hasImplicitComdat(RawLinkage)) {
NewGV->setComdat(reinterpret_cast<Comdat *>(1));
}
break;
}
// FUNCTION: [type, callingconv, isproto, linkage, paramattr,
@ -2238,8 +2214,7 @@ std::error_code BitcodeReader::ParseModule(bool Resume) {
Func->setCallingConv(static_cast<CallingConv::ID>(Record[1]));
bool isProto = Record[2];
uint64_t RawLinkage = Record[3];
Func->setLinkage(getDecodedLinkage(RawLinkage));
Func->setLinkage(getDecodedLinkage(Record[3]));
Func->setAttributes(getAttributes(Record[4]));
Func->setAlignment((1 << Record[5]) >> 1);
@ -2267,16 +2242,13 @@ std::error_code BitcodeReader::ParseModule(bool Resume) {
if (Record.size() > 11)
Func->setDLLStorageClass(GetDecodedDLLStorageClass(Record[11]));
else
UpgradeDLLImportExportLinkage(Func, RawLinkage);
UpgradeDLLImportExportLinkage(Func, Record[3]);
if (Record.size() > 12) {
if (Record.size() > 12)
if (unsigned ComdatID = Record[12]) {
assert(ComdatID <= ComdatList.size());
Func->setComdat(ComdatList[ComdatID - 1]);
}
} else if (hasImplicitComdat(RawLinkage)) {
Func->setComdat(reinterpret_cast<Comdat *>(1));
}
if (Record.size() > 13 && Record[13] != 0)
FunctionPrefixes.push_back(std::make_pair(Func, Record[13]-1));

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@ -480,13 +480,13 @@ static unsigned getEncodedLinkage(const GlobalValue &GV) {
case GlobalValue::ExternalLinkage:
return 0;
case GlobalValue::WeakAnyLinkage:
return 16;
return 1;
case GlobalValue::AppendingLinkage:
return 2;
case GlobalValue::InternalLinkage:
return 3;
case GlobalValue::LinkOnceAnyLinkage:
return 18;
return 4;
case GlobalValue::ExternalWeakLinkage:
return 7;
case GlobalValue::CommonLinkage:
@ -494,9 +494,9 @@ static unsigned getEncodedLinkage(const GlobalValue &GV) {
case GlobalValue::PrivateLinkage:
return 9;
case GlobalValue::WeakODRLinkage:
return 17;
return 10;
case GlobalValue::LinkOnceODRLinkage:
return 19;
return 11;
case GlobalValue::AvailableExternallyLinkage:
return 12;
}
@ -629,7 +629,7 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
Log2_32_Ceil(MaxGlobalType+1)));
Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Constant.
Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Initializer.
Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // Linkage.
Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // Linkage.
if (MaxAlignment == 0) // Alignment.
Abbv->Add(BitCodeAbbrevOp(0));
else {

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@ -257,7 +257,8 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
// 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 ((EmitUniquedSection && !Kind.isCommon()) || GV->hasComdat()) {
if ((GV->isWeakForLinker() || EmitUniquedSection || GV->hasComdat()) &&
!Kind.isCommon()) {
StringRef Prefix = getSectionPrefixForGlobal(Kind);
SmallString<128> Name(Prefix);
@ -265,9 +266,12 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
StringRef Group = "";
unsigned Flags = getELFSectionFlags(Kind);
if (const Comdat *C = getELFComdat(GV)) {
Flags |= ELF::SHF_GROUP;
if (GV->isWeakForLinker() || GV->hasComdat()) {
if (const Comdat *C = getELFComdat(GV))
Group = C->getName();
else
Group = Name.substr(Prefix.size());
Flags |= ELF::SHF_GROUP;
}
return getContext().getELFSection(Name.str(),
@ -797,7 +801,7 @@ const MCSection *TargetLoweringObjectFileCOFF::getExplicitSectionGlobal(
unsigned Characteristics = getCOFFSectionFlags(Kind);
StringRef Name = GV->getSection();
StringRef COMDATSymName = "";
if (GV->hasComdat()) {
if ((GV->isWeakForLinker() || GV->hasComdat()) && !Kind.isCommon()) {
Selection = getSelectionForCOFF(GV);
const GlobalValue *ComdatGV;
if (Selection == COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE)
@ -844,7 +848,12 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
else
EmitUniquedSection = TM.getDataSections();
if ((EmitUniquedSection && !Kind.isCommon()) || GV->hasComdat()) {
// 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.
// Section names depend on the name of the symbol which is not feasible if the
// symbol has private linkage.
if ((GV->isWeakForLinker() || EmitUniquedSection || GV->hasComdat()) &&
!Kind.isCommon()) {
const char *Name = getCOFFSectionNameForUniqueGlobal(Kind);
unsigned Characteristics = getCOFFSectionFlags(Kind);

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@ -105,6 +105,7 @@ void XCoreAsmPrinter::emitArrayBound(MCSymbol *Sym, const GlobalVariable *GV) {
OutContext));
if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
GV->hasCommonLinkage()) {
// TODO Use COMDAT groups for LinkOnceLinkage
OutStreamer.EmitSymbolAttribute(SymGlob, MCSA_Weak);
}
}
@ -139,6 +140,7 @@ void XCoreAsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
emitArrayBound(GVSym, GV);
OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
// TODO Use COMDAT groups for LinkOnceLinkage
if (GV->hasWeakLinkage() || GV->hasLinkOnceLinkage() ||
GV->hasCommonLinkage())
OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);

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@ -33,13 +33,13 @@
; CHECK: @available_externally.var = available_externally constant i32 0{{$}}
@linkonce.var = linkonce constant i32 0
; CHECK: @linkonce.var = linkonce constant i32 0, comdat{{$}}
; CHECK: @linkonce.var = linkonce constant i32 0{{$}}
@weak.var = weak constant i32 0
; CHECK: @weak.var = weak constant i32 0, comdat{{$}}
; CHECK: @weak.var = weak constant i32 0{{$}}
@linkonce_odr.var = linkonce_odr constant i32 0
; CHECK: @linkonce_odr.var = linkonce_odr constant i32 0, comdat{{$}}
; CHECK: @linkonce_odr.var = linkonce_odr constant i32 0{{$}}
@linkonce_odr_auto_hide.var = linkonce_odr_auto_hide constant i32 0
; CHECK: @linkonce_odr_auto_hide.var = constant i32 0{{$}}
@ -90,19 +90,19 @@ define available_externally void @available_externally()
}
define linkonce void @linkonce()
; CHECK: define linkonce void @linkonce() comdat {
; CHECK: define linkonce void @linkonce() {
{
ret void
}
define weak void @weak()
; CHECK: define weak void @weak() comdat {
; CHECK: define weak void @weak() {
{
ret void
}
define linkonce_odr void @linkonce_odr()
; CHECK: define linkonce_odr void @linkonce_odr() comdat {
; CHECK: define linkonce_odr void @linkonce_odr() {
{
ret void
}

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@ -0,0 +1,16 @@
; RUN: llc < %s -mtriple=arm-linux-gnueabi | FileCheck %s -check-prefix=ARMGNUEABI
; Checking that a comdat group gets generated correctly for a static member
; of instantiated C++ templates.
; see http://sourcery.mentor.com/public/cxx-abi/abi.html#vague-itemplate
; section 5.2.6 Instantiated templates
; "Any static member data object is emitted in a COMDAT identified by its mangled
; name, in any object file with a reference to its name symbol."
; Case 1: variable is not explicitly initialized, and ends up in a .bss section
; ARMGNUEABI: .section .bss._ZN1CIiE1iE,"aGw",%nobits,_ZN1CIiE1iE,comdat
@_ZN1CIiE1iE = weak_odr global i32 0, align 4
; Case 2: variable is explicitly initialized, and ends up in a .data section
; ARMGNUEABI: .section .data._ZN1CIiE1jE,"aGw",%progbits,_ZN1CIiE1jE,comdat
@_ZN1CIiE1jE = weak_odr global i32 12, align 4

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@ -16,7 +16,7 @@ entry:
ret void
}
; CHECK: .text
; CHECK: .section .text.test3,"axG",%progbits,test3,comdat
; CHECK: .weak test3
; CHECK: .type test3,%function
define linkonce_odr void @test3() {

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@ -17,16 +17,19 @@ define dllexport void @f2() unnamed_addr {
ret void
}
; CHECK: .section .text,"xr",discard,lnk1
; CHECK: .globl lnk1
define linkonce_odr dllexport void @lnk1() {
ret void
}
; CHECK: .section .text,"xr",discard,lnk2
; CHECK: .globl lnk2
define linkonce_odr dllexport void @lnk2() alwaysinline {
ret void
}
; CHECK: .section .text,"xr",discard,weak1
; CHECK: .globl weak1
define weak_odr dllexport void @weak1() {
ret void
@ -44,9 +47,11 @@ define weak_odr dllexport void @weak1() {
; CHECK: .comm Var3
@Var3 = common dllexport global i32 0, align 4
; CHECK: .section .data,"wd",discard,WeakVar1
; CHECK: .globl WeakVar1
@WeakVar1 = weak_odr dllexport global i32 1, align 4
; CHECK: .section .rdata,"rd",discard,WeakVar2
; CHECK: .globl WeakVar2
@WeakVar2 = weak_odr dllexport unnamed_addr constant i32 1

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@ -36,16 +36,19 @@ define dllexport x86_thiscallcc void @thisfun() nounwind {
ret void
}
; CHECK: .section .text,"xr",discard,_lnk1
; CHECK: .globl _lnk1
define linkonce_odr dllexport void @lnk1() {
ret void
}
; CHECK: .section .text,"xr",discard,_lnk2
; CHECK: .globl _lnk2
define linkonce_odr dllexport void @lnk2() alwaysinline {
ret void
}
; CHECK: .section .text,"xr",discard,_weak1
; CHECK: .globl _weak1
define weak_odr dllexport void @weak1() {
ret void
@ -63,9 +66,11 @@ define weak_odr dllexport void @weak1() {
; CHECK: .comm _Var3
@Var3 = common dllexport global i32 0, align 4
; CHECK: .section .data,"wd",discard,_WeakVar1
; CHECK: .globl _WeakVar1
@WeakVar1 = weak_odr dllexport global i32 1, align 4
; CHECK: .section .rdata,"rd",discard,_WeakVar2
; CHECK: .globl _WeakVar2
@WeakVar2 = weak_odr dllexport unnamed_addr constant i32 1

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@ -85,6 +85,7 @@ define void @F1() {
@"foo bar" = linkonce global i32 42
; LINUX: .type "foo bar",@object
; LINUX: .section ".data.foo bar","aGw",@progbits,"foo bar",comdat
; LINUX: .weak "foo bar"
; LINUX: "foo bar":
@ -97,6 +98,7 @@ define void @F1() {
@G6 = weak_odr unnamed_addr constant [1 x i8] c"\01"
; LINUX: .type G6,@object
; LINUX: .section .rodata.G6,"aG",@progbits,G6,comdat
; LINUX: .weak G6
; LINUX: G6:
; LINUX: .byte 1

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@ -0,0 +1,16 @@
; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu | FileCheck %s -check-prefix=X86LINUX
; Checking that a comdat group gets generated correctly for a static member
; of instantiated C++ templates.
; see http://sourcery.mentor.com/public/cxx-abi/abi.html#vague-itemplate
; section 5.2.6 Instantiated templates
; "Any static member data object is emitted in a COMDAT identified by its mangled
; name, in any object file with a reference to its name symbol."
; Case 1: variable is not explicitly initialized, and ends up in a .bss section
; X86LINUX: .section .bss._ZN1CIiE1iE,"aGw",@nobits,_ZN1CIiE1iE,comdat
@_ZN1CIiE1iE = weak_odr global i32 0, align 4
; Case 2: variable is explicitly initialized, and ends up in a .data section
; X86LINUX: .section .data._ZN1CIiE1jE,"aGw",@progbits,_ZN1CIiE1jE,comdat
@_ZN1CIiE1jE = weak_odr global i32 12, align 4

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@ -10,7 +10,7 @@
declare void @_Z3bari(i32)
; CHECK-LINUX: _Z3fooILi1EEvi:
; CHECK-LINUX: .text._Z3fooILi1EEvi,"axG",@progbits,_Z3fooILi1EEvi,comdat
define linkonce void @_Z3fooILi1EEvi(i32 %Y) nounwind {
entry:
; CHECK: L0$pb

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@ -5,6 +5,5 @@
@"\01?thingy@@3Ufoo@@B" = global %struct.foo zeroinitializer, align 4
; CHECK: .bss
$thingy_linkonce = comdat any
@thingy_linkonce = linkonce_odr global %struct.foo zeroinitializer, comdat, align 4
@thingy_linkonce = linkonce_odr global %struct.foo zeroinitializer, align 4
; CHECK: .section .bss,"wb",discard,_thingy_linkonce

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@ -8,4 +8,4 @@ define void @f() {
; CHECK: .section .CRT$XLB,"rd"
@weak_array = weak_odr unnamed_addr constant [1 x i8*] [i8* bitcast (void ()* @f to i8*)]
; CHECK: .section .rdata,"rd"
; CHECK: .section .rdata,"rd",discard,weak_array

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@ -0,0 +1,48 @@
; Test that weak functions and globals are placed into selectany COMDAT
; sections with the mangled name as suffix. Ensure that the weak linkage
; type is not ignored by the backend if the section was specialized.
;
; RUN: llc -mtriple=i686-pc-win32 %s -o - | FileCheck %s --check-prefix=X86
; RUN: llc -mtriple=i686-pc-mingw32 %s -o - | FileCheck %s --check-prefix=X86
; RUN: llc -mtriple=x86_64-pc-win32 %s -o - | FileCheck %s --check-prefix=X64
; RUN: llc -mtriple=x86_64-pc-mingw32 %s -o - | FileCheck %s --check-prefix=X64
; Mangled function
; X86: .section .text,"xr",discard,__Z3foo
; X86: .globl __Z3foo
;
; X64: .section .text,"xr",discard,_Z3foo
; X64: .globl _Z3foo
define weak void @_Z3foo() {
ret void
}
; Unmangled function
; X86: .section .sect,"xr",discard,_f
; X86: .globl _f
;
; X64: .section .sect,"xr",discard,f
; X64: .globl f
define weak void @f() section ".sect" {
ret void
}
; Weak global
; X86: .section .data,"rd",discard,_a
; X86: .globl _a
; X86: .zero 12
;
; X64: .section .data,"rd",discard,a
; X64: .globl a
; X64: .zero 12
@a = weak unnamed_addr constant { i32, i32, i32 } { i32 0, i32 0, i32 0}, section ".data"
; X86: .section .tls$,"wd",discard,_b
; X86: .globl _b
; X86: .long 0
;
; X64: .section .tls$,"wd",discard,b
; X64: .globl b
; X64: .long 0
@b = weak_odr thread_local global i32 0, align 4