Rename isWeakForLinker to mayBeOverridden. Use it

instead of hasWeakLinkage in a bunch of optimization
passes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56782 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Duncan Sands 2008-09-29 11:25:42 +00:00
parent 7ab5799f75
commit 5df3186f59
16 changed files with 35 additions and 30 deletions

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@ -111,9 +111,10 @@ public:
void setLinkage(LinkageTypes LT) { Linkage = LT; }
LinkageTypes getLinkage() const { return Linkage; }
/// isWeakForLinker - Determines if symbol is weak for linker having weak or
/// linkonce or common or extweak LLVM linkage.
bool isWeakForLinker() const {
/// mayBeOverridden - Whether the definition of this global may be replaced
/// at link time. For example, if a function has weak linkage then the code
/// defining it may be replaced by different code.
bool mayBeOverridden() const {
return (Linkage == WeakLinkage ||
Linkage == LinkOnceLinkage ||
Linkage == CommonLinkage ||

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@ -477,7 +477,7 @@ static bool GetLinkageResult(GlobalValue *Dest, const GlobalValue *Src,
"': can only link appending global with another appending global!");
LinkFromSrc = true; // Special cased.
LT = Src->getLinkage();
} else if (Src->isWeakForLinker()) {
} else if (Src->mayBeOverridden()) {
// At this point we know that Dest has LinkOnce, External*, Weak, Common,
// or DLL* linkage.
if ((Dest->hasLinkOnceLinkage() &&
@ -489,7 +489,7 @@ static bool GetLinkageResult(GlobalValue *Dest, const GlobalValue *Src,
LinkFromSrc = false;
LT = Dest->getLinkage();
}
} else if (Dest->isWeakForLinker()) {
} else if (Dest->mayBeOverridden()) {
// At this point we know that Src has External* or DLL* linkage.
if (Src->hasExternalWeakLinkage()) {
LinkFromSrc = false;
@ -757,7 +757,7 @@ static bool LinkAlias(Module *Dest, const Module *Src,
} else if (GlobalVariable *DGVar = dyn_cast_or_null<GlobalVariable>(DGV)) {
// The only allowed way is to link alias with external declaration or weak
// symbol..
if (DGVar->isDeclaration() || DGVar->isWeakForLinker()) {
if (DGVar->isDeclaration() || DGVar->mayBeOverridden()) {
// But only if aliasee is global too...
if (!isa<GlobalVariable>(DAliasee))
return Error(Err, "Global-Alias Collision on '" + SGA->getName() +
@ -786,7 +786,7 @@ static bool LinkAlias(Module *Dest, const Module *Src,
} else if (Function *DF = dyn_cast_or_null<Function>(DGV)) {
// The only allowed way is to link alias with external declaration or weak
// symbol...
if (DF->isDeclaration() || DF->isWeakForLinker()) {
if (DF->isDeclaration() || DF->mayBeOverridden()) {
// But only if aliasee is function too...
if (!isa<Function>(DAliasee))
return Error(Err, "Function-Alias Collision on '" + SGA->getName() +
@ -862,10 +862,10 @@ static bool LinkGlobalInits(Module *Dest, const Module *Src,
if (DGV->getInitializer() != SInit)
return Error(Err, "Global Variable Collision on '" + SGV->getName() +
"': global variables have different initializers");
} else if (DGV->isWeakForLinker()) {
} else if (DGV->mayBeOverridden()) {
// Nothing is required, mapped values will take the new global
// automatically.
} else if (SGV->isWeakForLinker()) {
} else if (SGV->mayBeOverridden()) {
// Nothing is required, mapped values will take the new global
// automatically.
} else if (DGV->hasAppendingLinkage()) {

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@ -871,7 +871,7 @@ void ARMAsmPrinter::printModuleLevelGV(const GlobalVariable* GVar) {
}
}
if (GVar->hasInternalLinkage() || GVar->isWeakForLinker()) {
if (GVar->hasInternalLinkage() || GVar->mayBeOverridden()) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (TAI->getLCOMMDirective() != NULL) {

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@ -73,7 +73,7 @@ DarwinTargetAsmInfo::emitUsedDirectiveFor(const GlobalValue* GV,
const Section*
DarwinTargetAsmInfo::SelectSectionForGlobal(const GlobalValue *GV) const {
SectionKind::Kind Kind = SectionKindForGlobal(GV);
bool isWeak = GV->isWeakForLinker();
bool isWeak = GV->mayBeOverridden();
bool isNonStatic = (DTM->getRelocationModel() != Reloc::Static);
switch (Kind) {

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@ -55,7 +55,7 @@ ELFTargetAsmInfo::SelectSectionForGlobal(const GlobalValue *GV) const {
return getNamedSection(Name.c_str(), Flags);
}
} else if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV)) {
if (GVar->isWeakForLinker()) {
if (GVar->mayBeOverridden()) {
std::string Name = UniqueSectionForGlobal(GVar, Kind);
unsigned Flags = SectionFlagsForGlobal(GVar, Name.c_str());
return getNamedSection(Name.c_str(), Flags);

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@ -275,7 +275,7 @@ void IA64AsmPrinter::printModuleLevelGV(const GlobalVariable* GVar) {
if (C->isNullValue() && !GVar->hasSection()) {
if (!GVar->isThreadLocal() &&
(GVar->hasInternalLinkage() || GVar->isWeakForLinker())) {
(GVar->hasInternalLinkage() || GVar->mayBeOverridden())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (GVar->hasInternalLinkage()) {

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@ -504,7 +504,7 @@ printModuleLevelGV(const GlobalVariable* GVar) {
if (C->isNullValue() && !GVar->hasSection()) {
if (!GVar->isThreadLocal() &&
(GVar->hasInternalLinkage() || GVar->isWeakForLinker())) {
(GVar->hasInternalLinkage() || GVar->mayBeOverridden())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (GVar->hasInternalLinkage())

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@ -85,7 +85,7 @@ SelectSectionForGlobal(const GlobalValue *GV) const {
SectionKind::Kind K = SectionKindForGlobal(GV);
const GlobalVariable *GVA = dyn_cast<GlobalVariable>(GV);
if (GVA && (!GVA->isWeakForLinker()))
if (GVA && (!GVA->mayBeOverridden()))
switch (K) {
case SectionKind::SmallData:
return getSmallDataSection();

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@ -675,7 +675,7 @@ void PPCLinuxAsmPrinter::printModuleLevelGV(const GlobalVariable* GVar) {
if (C->isNullValue() && /* FIXME: Verify correct */
!GVar->hasSection() &&
(GVar->hasInternalLinkage() || GVar->hasExternalLinkage() ||
GVar->isWeakForLinker())) {
GVar->mayBeOverridden())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (GVar->hasExternalLinkage()) {
@ -900,7 +900,7 @@ void PPCDarwinAsmPrinter::printModuleLevelGV(const GlobalVariable* GVar) {
if (C->isNullValue() && /* FIXME: Verify correct */
!GVar->hasSection() &&
(GVar->hasInternalLinkage() || GVar->hasExternalLinkage() ||
GVar->isWeakForLinker())) {
GVar->mayBeOverridden())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (GVar->hasExternalLinkage()) {

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@ -253,7 +253,7 @@ void SparcAsmPrinter::printModuleLevelGV(const GlobalVariable* GVar) {
if (C->isNullValue() && !GVar->hasSection()) {
if (!GVar->isThreadLocal() &&
(GVar->hasInternalLinkage() || GVar->isWeakForLinker())) {
(GVar->hasInternalLinkage() || GVar->mayBeOverridden())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (GVar->hasInternalLinkage())

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@ -240,7 +240,7 @@ TargetAsmInfo::SectionFlagsForGlobal(const GlobalValue *GV,
assert(0 && "Unexpected section kind!");
}
if (GV->isWeakForLinker())
if (GV->mayBeOverridden())
Flags |= SectionFlags::Linkonce;
}
@ -291,7 +291,7 @@ const Section*
TargetAsmInfo::SelectSectionForGlobal(const GlobalValue *GV) const {
SectionKind::Kind Kind = SectionKindForGlobal(GV);
if (GV->isWeakForLinker()) {
if (GV->mayBeOverridden()) {
std::string Name = UniqueSectionForGlobal(GV, Kind);
unsigned Flags = SectionFlagsForGlobal(GV, Name.c_str());
return getNamedSection(Name.c_str(), Flags);

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@ -383,7 +383,7 @@ void X86ATTAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
if (shouldPrintStub(TM, Subtarget)) {
// Link-once, declaration, or Weakly-linked global variables need
// non-lazily-resolved stubs
if (GV->isDeclaration() || GV->isWeakForLinker()) {
if (GV->isDeclaration() || GV->mayBeOverridden()) {
// Dynamically-resolved functions need a stub for the function.
if (isCallOp && isa<Function>(GV)) {
// Function stubs are no longer needed for Mac OS X 10.5 and up.
@ -790,7 +790,7 @@ void X86ATTAsmPrinter::printModuleLevelGV(const GlobalVariable* GVar) {
}
if (!GVar->isThreadLocal() &&
(GVar->hasInternalLinkage() || GVar->isWeakForLinker())) {
(GVar->hasInternalLinkage() || GVar->mayBeOverridden())) {
if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
if (TAI->getLCOMMDirective() != NULL) {

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@ -63,7 +63,7 @@ bool AddReadAttrs::runOnSCC(const std::vector<CallGraphNode *> &SCC) {
// Definitions with weak linkage may be overridden at linktime with
// something that writes memory, so treat them like declarations.
if (F->isDeclaration() || F->hasWeakLinkage()) {
if (F->isDeclaration() || F->mayBeOverridden()) {
if (!F->onlyReadsMemory())
// May write memory.
return false;

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@ -155,7 +155,7 @@ bool IPCP::PropagateConstantReturn(Function &F) {
// If this function could be overridden later in the link stage, we can't
// propagate information about its results into callers.
if (F.hasLinkOnceLinkage() || F.hasWeakLinkage())
if (F.hasLinkOnceLinkage() || F.mayBeOverridden())
return false;
// Check to see if this function returns a constant.

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@ -76,7 +76,7 @@ bool PruneEH::runOnSCC(const std::vector<CallGraphNode *> &SCC) {
if (F == 0) {
SCCMightUnwind = true;
SCCMightReturn = true;
} else if (F->isDeclaration() || F->hasWeakLinkage()) {
} else if (F->isDeclaration() || F->mayBeOverridden()) {
SCCMightUnwind |= !F->doesNotThrow();
SCCMightReturn |= !F->doesNotReturn();
} else {

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@ -174,17 +174,21 @@ int InlineCostAnalyzer::getInlineCost(CallSite CS,
Instruction *TheCall = CS.getInstruction();
Function *Callee = CS.getCalledFunction();
const Function *Caller = TheCall->getParent()->getParent();
// Don't inline a directly recursive call.
if (Caller == Callee ||
// Don't inline functions which can be redefined at link-time to mean
// something else. link-once linkage is ok though.
Callee->hasWeakLinkage() ||
// something else.
// FIXME: We allow link-once linkage since in practice all versions of
// the function have the same body (C++ ODR) - but the LLVM definition
// of LinkOnceLinkage doesn't require this.
(Callee->mayBeOverridden() && !Callee->hasLinkOnceLinkage()
) ||
// Don't inline functions marked noinline.
NeverInline.count(Callee))
return 2000000000;
// InlineCost - This value measures how good of an inline candidate this call
// site is to inline. A lower inline cost make is more likely for the call to
// be inlined. This value may go negative.