llvm-6502/lib/CodeGen/MachineModuleInfo.cpp

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//===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Module.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/ADT/PointerUnion.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
using namespace llvm::dwarf;
// Handle the Pass registration stuff necessary to use TargetData's.
INITIALIZE_PASS(MachineModuleInfo, "machinemoduleinfo",
"Machine Module Information", false, false)
char MachineModuleInfo::ID = 0;
// Out of line virtual method.
MachineModuleInfoImpl::~MachineModuleInfoImpl() {}
namespace llvm {
class MMIAddrLabelMapCallbackPtr : CallbackVH {
MMIAddrLabelMap *Map;
public:
MMIAddrLabelMapCallbackPtr() : Map(0) {}
MMIAddrLabelMapCallbackPtr(Value *V) : CallbackVH(V), Map(0) {}
void setPtr(BasicBlock *BB) {
ValueHandleBase::operator=(BB);
}
void setMap(MMIAddrLabelMap *map) { Map = map; }
virtual void deleted();
virtual void allUsesReplacedWith(Value *V2);
};
class MMIAddrLabelMap {
MCContext &Context;
struct AddrLabelSymEntry {
/// Symbols - The symbols for the label. This is a pointer union that is
/// either one symbol (the common case) or a list of symbols.
PointerUnion<MCSymbol *, std::vector<MCSymbol*>*> Symbols;
Function *Fn; // The containing function of the BasicBlock.
unsigned Index; // The index in BBCallbacks for the BasicBlock.
};
DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry> AddrLabelSymbols;
/// BBCallbacks - Callbacks for the BasicBlock's that we have entries for. We
/// use this so we get notified if a block is deleted or RAUWd.
std::vector<MMIAddrLabelMapCallbackPtr> BBCallbacks;
/// DeletedAddrLabelsNeedingEmission - This is a per-function list of symbols
/// whose corresponding BasicBlock got deleted. These symbols need to be
/// emitted at some point in the file, so AsmPrinter emits them after the
/// function body.
DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >
DeletedAddrLabelsNeedingEmission;
public:
MMIAddrLabelMap(MCContext &context) : Context(context) {}
~MMIAddrLabelMap() {
assert(DeletedAddrLabelsNeedingEmission.empty() &&
"Some labels for deleted blocks never got emitted");
// Deallocate any of the 'list of symbols' case.
for (DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry>::iterator
I = AddrLabelSymbols.begin(), E = AddrLabelSymbols.end(); I != E; ++I)
if (I->second.Symbols.is<std::vector<MCSymbol*>*>())
delete I->second.Symbols.get<std::vector<MCSymbol*>*>();
}
MCSymbol *getAddrLabelSymbol(BasicBlock *BB);
std::vector<MCSymbol*> getAddrLabelSymbolToEmit(BasicBlock *BB);
void takeDeletedSymbolsForFunction(Function *F,
std::vector<MCSymbol*> &Result);
void UpdateForDeletedBlock(BasicBlock *BB);
void UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New);
};
}
MCSymbol *MMIAddrLabelMap::getAddrLabelSymbol(BasicBlock *BB) {
assert(BB->hasAddressTaken() &&
"Shouldn't get label for block without address taken");
AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
// If we already had an entry for this block, just return it.
if (!Entry.Symbols.isNull()) {
assert(BB->getParent() == Entry.Fn && "Parent changed");
if (Entry.Symbols.is<MCSymbol*>())
return Entry.Symbols.get<MCSymbol*>();
return (*Entry.Symbols.get<std::vector<MCSymbol*>*>())[0];
}
// Otherwise, this is a new entry, create a new symbol for it and add an
// entry to BBCallbacks so we can be notified if the BB is deleted or RAUWd.
BBCallbacks.push_back(BB);
BBCallbacks.back().setMap(this);
Entry.Index = BBCallbacks.size()-1;
Entry.Fn = BB->getParent();
MCSymbol *Result = Context.CreateTempSymbol();
Entry.Symbols = Result;
return Result;
}
std::vector<MCSymbol*>
MMIAddrLabelMap::getAddrLabelSymbolToEmit(BasicBlock *BB) {
assert(BB->hasAddressTaken() &&
"Shouldn't get label for block without address taken");
AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
std::vector<MCSymbol*> Result;
// If we already had an entry for this block, just return it.
if (Entry.Symbols.isNull())
Result.push_back(getAddrLabelSymbol(BB));
else if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>())
Result.push_back(Sym);
else
Result = *Entry.Symbols.get<std::vector<MCSymbol*>*>();
return Result;
}
/// takeDeletedSymbolsForFunction - If we have any deleted symbols for F, return
/// them.
void MMIAddrLabelMap::
takeDeletedSymbolsForFunction(Function *F, std::vector<MCSymbol*> &Result) {
DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >::iterator I =
DeletedAddrLabelsNeedingEmission.find(F);
// If there are no entries for the function, just return.
if (I == DeletedAddrLabelsNeedingEmission.end()) return;
// Otherwise, take the list.
std::swap(Result, I->second);
DeletedAddrLabelsNeedingEmission.erase(I);
}
void MMIAddrLabelMap::UpdateForDeletedBlock(BasicBlock *BB) {
// If the block got deleted, there is no need for the symbol. If the symbol
// was already emitted, we can just forget about it, otherwise we need to
// queue it up for later emission when the function is output.
AddrLabelSymEntry Entry = AddrLabelSymbols[BB];
AddrLabelSymbols.erase(BB);
assert(!Entry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
BBCallbacks[Entry.Index] = 0; // Clear the callback.
assert((BB->getParent() == 0 || BB->getParent() == Entry.Fn) &&
"Block/parent mismatch");
// Handle both the single and the multiple symbols cases.
if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>()) {
if (Sym->isDefined())
return;
// If the block is not yet defined, we need to emit it at the end of the
// function. Add the symbol to the DeletedAddrLabelsNeedingEmission list
// for the containing Function. Since the block is being deleted, its
// parent may already be removed, we have to get the function from 'Entry'.
DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
} else {
std::vector<MCSymbol*> *Syms = Entry.Symbols.get<std::vector<MCSymbol*>*>();
for (unsigned i = 0, e = Syms->size(); i != e; ++i) {
MCSymbol *Sym = (*Syms)[i];
if (Sym->isDefined()) continue; // Ignore already emitted labels.
// If the block is not yet defined, we need to emit it at the end of the
// function. Add the symbol to the DeletedAddrLabelsNeedingEmission list
// for the containing Function. Since the block is being deleted, its
// parent may already be removed, we have to get the function from
// 'Entry'.
DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
}
// The entry is deleted, free the memory associated with the symbol list.
delete Syms;
}
}
void MMIAddrLabelMap::UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New) {
// Get the entry for the RAUW'd block and remove it from our map.
AddrLabelSymEntry OldEntry = AddrLabelSymbols[Old];
AddrLabelSymbols.erase(Old);
assert(!OldEntry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
AddrLabelSymEntry &NewEntry = AddrLabelSymbols[New];
// If New is not address taken, just move our symbol over to it.
if (NewEntry.Symbols.isNull()) {
BBCallbacks[OldEntry.Index].setPtr(New); // Update the callback.
NewEntry = OldEntry; // Set New's entry.
return;
}
BBCallbacks[OldEntry.Index] = 0; // Update the callback.
// Otherwise, we need to add the old symbol to the new block's set. If it is
// just a single entry, upgrade it to a symbol list.
if (MCSymbol *PrevSym = NewEntry.Symbols.dyn_cast<MCSymbol*>()) {
std::vector<MCSymbol*> *SymList = new std::vector<MCSymbol*>();
SymList->push_back(PrevSym);
NewEntry.Symbols = SymList;
}
std::vector<MCSymbol*> *SymList =
NewEntry.Symbols.get<std::vector<MCSymbol*>*>();
// If the old entry was a single symbol, add it.
if (MCSymbol *Sym = OldEntry.Symbols.dyn_cast<MCSymbol*>()) {
SymList->push_back(Sym);
return;
}
// Otherwise, concatenate the list.
std::vector<MCSymbol*> *Syms =OldEntry.Symbols.get<std::vector<MCSymbol*>*>();
SymList->insert(SymList->end(), Syms->begin(), Syms->end());
delete Syms;
}
void MMIAddrLabelMapCallbackPtr::deleted() {
Map->UpdateForDeletedBlock(cast<BasicBlock>(getValPtr()));
}
void MMIAddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) {
Map->UpdateForRAUWBlock(cast<BasicBlock>(getValPtr()), cast<BasicBlock>(V2));
}
//===----------------------------------------------------------------------===//
MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI,
const TargetAsmInfo *TAI)
: ImmutablePass(ID), Context(MAI, TAI),
ObjFileMMI(0),
CurCallSite(0), CallsEHReturn(0), CallsUnwindInit(0), DbgInfoAvailable(false),
CallsExternalVAFunctionWithFloatingPointArguments(false) {
initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
// Always emit some info, by default "no personality" info.
Personalities.push_back(NULL);
AddrLabelSymbols = 0;
TheModule = 0;
}
MachineModuleInfo::MachineModuleInfo()
: ImmutablePass(ID), Context(*(MCAsmInfo*)0, NULL) {
assert(0 && "This MachineModuleInfo constructor should never be called, MMI "
"should always be explicitly constructed by LLVMTargetMachine");
abort();
}
MachineModuleInfo::~MachineModuleInfo() {
delete ObjFileMMI;
// FIXME: Why isn't doFinalization being called??
//assert(AddrLabelSymbols == 0 && "doFinalization not called");
delete AddrLabelSymbols;
AddrLabelSymbols = 0;
}
/// doInitialization - Initialize the state for a new module.
///
bool MachineModuleInfo::doInitialization() {
assert(AddrLabelSymbols == 0 && "Improperly initialized");
return false;
}
/// doFinalization - Tear down the state after completion of a module.
///
bool MachineModuleInfo::doFinalization() {
delete AddrLabelSymbols;
AddrLabelSymbols = 0;
return false;
}
/// EndFunction - Discard function meta information.
///
void MachineModuleInfo::EndFunction() {
// Clean up frame info.
FrameMoves.clear();
// Clean up exception info.
LandingPads.clear();
CallSiteMap.clear();
TypeInfos.clear();
FilterIds.clear();
FilterEnds.clear();
CallsEHReturn = 0;
CallsUnwindInit = 0;
VariableDbgInfo.clear();
}
/// AnalyzeModule - Scan the module for global debug information.
///
void MachineModuleInfo::AnalyzeModule(const Module &M) {
// Insert functions in the llvm.used array (but not llvm.compiler.used) into
// UsedFunctions.
const GlobalVariable *GV = M.getGlobalVariable("llvm.used");
if (!GV || !GV->hasInitializer()) return;
// Should be an array of 'i8*'.
const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
if (InitList == 0) return;
for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
if (const Function *F =
dyn_cast<Function>(InitList->getOperand(i)->stripPointerCasts()))
UsedFunctions.insert(F);
}
//===- Address of Block Management ----------------------------------------===//
/// getAddrLabelSymbol - Return the symbol to be used for the specified basic
/// block when its address is taken. This cannot be its normal LBB label
/// because the block may be accessed outside its containing function.
MCSymbol *MachineModuleInfo::getAddrLabelSymbol(const BasicBlock *BB) {
// Lazily create AddrLabelSymbols.
if (AddrLabelSymbols == 0)
AddrLabelSymbols = new MMIAddrLabelMap(Context);
return AddrLabelSymbols->getAddrLabelSymbol(const_cast<BasicBlock*>(BB));
}
/// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified
/// basic block when its address is taken. If other blocks were RAUW'd to
/// this one, we may have to emit them as well, return the whole set.
std::vector<MCSymbol*> MachineModuleInfo::
getAddrLabelSymbolToEmit(const BasicBlock *BB) {
// Lazily create AddrLabelSymbols.
if (AddrLabelSymbols == 0)
AddrLabelSymbols = new MMIAddrLabelMap(Context);
return AddrLabelSymbols->getAddrLabelSymbolToEmit(const_cast<BasicBlock*>(BB));
}
/// takeDeletedSymbolsForFunction - If the specified function has had any
/// references to address-taken blocks generated, but the block got deleted,
/// return the symbol now so we can emit it. This prevents emitting a
/// reference to a symbol that has no definition.
void MachineModuleInfo::
takeDeletedSymbolsForFunction(const Function *F,
std::vector<MCSymbol*> &Result) {
// If no blocks have had their addresses taken, we're done.
if (AddrLabelSymbols == 0) return;
return AddrLabelSymbols->
takeDeletedSymbolsForFunction(const_cast<Function*>(F), Result);
}
//===- EH -----------------------------------------------------------------===//
/// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
/// specified MachineBasicBlock.
LandingPadInfo &MachineModuleInfo::getOrCreateLandingPadInfo
(MachineBasicBlock *LandingPad) {
unsigned N = LandingPads.size();
for (unsigned i = 0; i < N; ++i) {
LandingPadInfo &LP = LandingPads[i];
if (LP.LandingPadBlock == LandingPad)
return LP;
}
LandingPads.push_back(LandingPadInfo(LandingPad));
return LandingPads[N];
}
/// addInvoke - Provide the begin and end labels of an invoke style call and
/// associate it with a try landing pad block.
void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad,
MCSymbol *BeginLabel, MCSymbol *EndLabel) {
LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
LP.BeginLabels.push_back(BeginLabel);
LP.EndLabels.push_back(EndLabel);
}
/// addLandingPad - Provide the label of a try LandingPad block.
///
MCSymbol *MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) {
MCSymbol *LandingPadLabel = Context.CreateTempSymbol();
LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
LP.LandingPadLabel = LandingPadLabel;
return LandingPadLabel;
}
/// addPersonality - Provide the personality function for the exception
/// information.
void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad,
const Function *Personality) {
LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
LP.Personality = Personality;
for (unsigned i = 0; i < Personalities.size(); ++i)
if (Personalities[i] == Personality)
return;
// If this is the first personality we're adding go
// ahead and add it at the beginning.
if (Personalities[0] == NULL)
Personalities[0] = Personality;
else
Personalities.push_back(Personality);
}
/// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
///
void MachineModuleInfo::addCatchTypeInfo(MachineBasicBlock *LandingPad,
std::vector<const GlobalVariable *> &TyInfo) {
LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
for (unsigned N = TyInfo.size(); N; --N)
LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
}
/// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
///
void MachineModuleInfo::addFilterTypeInfo(MachineBasicBlock *LandingPad,
std::vector<const GlobalVariable *> &TyInfo) {
LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
std::vector<unsigned> IdsInFilter(TyInfo.size());
for (unsigned I = 0, E = TyInfo.size(); I != E; ++I)
IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
}
There is an impedance matching problem between LLVM and gcc exception handling: if an exception unwinds through an invoke, then execution must branch to the invoke's unwind target. We previously tried to enforce this by appending a cleanup action to every selector, however this does not always work correctly due to an optimization in the C++ unwinding runtime: if only cleanups would be run while unwinding an exception, then the program just terminates without actually executing the cleanups, as invoke semantics would require. I was hoping this wouldn't be a problem, but in fact it turns out to be the cause of all the remaining failures in the LLVM testsuite (these also fail with -enable-correct-eh-support, so turning on -enable-eh didn't make things worse!). Instead we need to append a full-blown catch-all to the end of each selector. The correct way of doing this depends on the personality function, i.e. it is language dependent, so can only be done by gcc. Thus this patch which generalizes the eh.selector intrinsic so that it can handle all possible kinds of action table entries (before it didn't accomodate cleanups): now 0 indicates a cleanup, and filters have to be specified using the number of type infos plus one rather than the number of type infos. Related gcc patches will cause Ada to pass a cleanup (0) to force the selector to always fire, while C++ will use a C++ catch-all (null). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41484 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-27 15:47:50 +00:00
/// addCleanup - Add a cleanup action for a landing pad.
///
void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) {
LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
LP.TypeIds.push_back(0);
}
/// TidyLandingPads - Remap landing pad labels and remove any deleted landing
/// pads.
void MachineModuleInfo::TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap) {
for (unsigned i = 0; i != LandingPads.size(); ) {
LandingPadInfo &LandingPad = LandingPads[i];
if (LandingPad.LandingPadLabel &&
!LandingPad.LandingPadLabel->isDefined() &&
(!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0))
LandingPad.LandingPadLabel = 0;
// Special case: we *should* emit LPs with null LP MBB. This indicates
// "nounwind" case.
if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
LandingPads.erase(LandingPads.begin() + i);
continue;
}
Fix PR1628. When exception handling is turned on, labels are generated bracketing each call (not just invokes). This is used to generate entries in the exception table required by the C++ personality. However it gets in the way of tail-merging. This patch solves the problem by no longer placing labels around ordinary calls. Instead we generate entries in the exception table that cover every instruction in the function that wasn't covered by an invoke range (the range given by the labels around the invoke). As an optimization, such entries are only generated for parts of the function that contain a call, since for the moment those are the only instructions that can throw an exception [1]. As a happy consequence, we now get a smaller exception table, since the same region can cover many calls. While there, I also implemented folding of invoke ranges - successive ranges are merged when safe to do so. Finally, if a selector contains only a cleanup, there's a special shorthand for it - place a 0 in the call-site entry. I implemented this while there. As a result, the exception table output (excluding filters) is now optimal - it cannot be made smaller [2]. The problem with throw filters is that folding them optimally is hard, and the benefit of folding them is minimal. [1] I tested that having trapping instructions (eg divide by zero) in such a region doesn't cause trouble. [2] It could be made smaller with the help of higher layers, eg by having branch folding reorder basic blocks ending in invokes with the same landing pad so they follow each other. I don't know if this is worth doing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41718 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-05 11:27:52 +00:00
for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) {
MCSymbol *BeginLabel = LandingPad.BeginLabels[j];
MCSymbol *EndLabel = LandingPad.EndLabels[j];
if ((BeginLabel->isDefined() ||
(LPMap && (*LPMap)[BeginLabel] != 0)) &&
(EndLabel->isDefined() ||
(LPMap && (*LPMap)[EndLabel] != 0))) continue;
LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
--j, --e;
}
Fix PR1628. When exception handling is turned on, labels are generated bracketing each call (not just invokes). This is used to generate entries in the exception table required by the C++ personality. However it gets in the way of tail-merging. This patch solves the problem by no longer placing labels around ordinary calls. Instead we generate entries in the exception table that cover every instruction in the function that wasn't covered by an invoke range (the range given by the labels around the invoke). As an optimization, such entries are only generated for parts of the function that contain a call, since for the moment those are the only instructions that can throw an exception [1]. As a happy consequence, we now get a smaller exception table, since the same region can cover many calls. While there, I also implemented folding of invoke ranges - successive ranges are merged when safe to do so. Finally, if a selector contains only a cleanup, there's a special shorthand for it - place a 0 in the call-site entry. I implemented this while there. As a result, the exception table output (excluding filters) is now optimal - it cannot be made smaller [2]. The problem with throw filters is that folding them optimally is hard, and the benefit of folding them is minimal. [1] I tested that having trapping instructions (eg divide by zero) in such a region doesn't cause trouble. [2] It could be made smaller with the help of higher layers, eg by having branch folding reorder basic blocks ending in invokes with the same landing pad so they follow each other. I don't know if this is worth doing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41718 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-05 11:27:52 +00:00
// Remove landing pads with no try-ranges.
if (LandingPads[i].BeginLabels.empty()) {
Fix PR1628. When exception handling is turned on, labels are generated bracketing each call (not just invokes). This is used to generate entries in the exception table required by the C++ personality. However it gets in the way of tail-merging. This patch solves the problem by no longer placing labels around ordinary calls. Instead we generate entries in the exception table that cover every instruction in the function that wasn't covered by an invoke range (the range given by the labels around the invoke). As an optimization, such entries are only generated for parts of the function that contain a call, since for the moment those are the only instructions that can throw an exception [1]. As a happy consequence, we now get a smaller exception table, since the same region can cover many calls. While there, I also implemented folding of invoke ranges - successive ranges are merged when safe to do so. Finally, if a selector contains only a cleanup, there's a special shorthand for it - place a 0 in the call-site entry. I implemented this while there. As a result, the exception table output (excluding filters) is now optimal - it cannot be made smaller [2]. The problem with throw filters is that folding them optimally is hard, and the benefit of folding them is minimal. [1] I tested that having trapping instructions (eg divide by zero) in such a region doesn't cause trouble. [2] It could be made smaller with the help of higher layers, eg by having branch folding reorder basic blocks ending in invokes with the same landing pad so they follow each other. I don't know if this is worth doing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41718 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-05 11:27:52 +00:00
LandingPads.erase(LandingPads.begin() + i);
continue;
}
// If there is no landing pad, ensure that the list of typeids is empty.
// If the only typeid is a cleanup, this is the same as having no typeids.
if (!LandingPad.LandingPadBlock ||
(LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
LandingPad.TypeIds.clear();
++i;
}
}
/// getTypeIDFor - Return the type id for the specified typeinfo. This is
/// function wide.
unsigned MachineModuleInfo::getTypeIDFor(const GlobalVariable *TI) {
for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
if (TypeInfos[i] == TI) return i + 1;
TypeInfos.push_back(TI);
return TypeInfos.size();
}
/// getFilterIDFor - Return the filter id for the specified typeinfos. This is
/// function wide.
int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) {
// If the new filter coincides with the tail of an existing filter, then
// re-use the existing filter. Folding filters more than this requires
// re-ordering filters and/or their elements - probably not worth it.
for (std::vector<unsigned>::iterator I = FilterEnds.begin(),
E = FilterEnds.end(); I != E; ++I) {
unsigned i = *I, j = TyIds.size();
while (i && j)
if (FilterIds[--i] != TyIds[--j])
goto try_next;
if (!j)
// The new filter coincides with range [i, end) of the existing filter.
return -(1 + i);
try_next:;
}
// Add the new filter.
int FilterID = -(1 + FilterIds.size());
FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
for (unsigned I = 0, N = TyIds.size(); I != N; ++I)
FilterIds.push_back(TyIds[I]);
FilterEnds.push_back(FilterIds.size());
FilterIds.push_back(0); // terminator
return FilterID;
}
/// getPersonality - Return the personality function for the current function.
const Function *MachineModuleInfo::getPersonality() const {
// FIXME: Until PR1414 will be fixed, we're using 1 personality function per
// function
return !LandingPads.empty() ? LandingPads[0].Personality : NULL;
}
/// getPersonalityIndex - Return unique index for current personality
/// function. NULL/first personality function should always get zero index.
unsigned MachineModuleInfo::getPersonalityIndex() const {
const Function* Personality = NULL;
// Scan landing pads. If there is at least one non-NULL personality - use it.
for (unsigned i = 0; i != LandingPads.size(); ++i)
if (LandingPads[i].Personality) {
Personality = LandingPads[i].Personality;
break;
}
for (unsigned i = 0; i < Personalities.size(); ++i) {
if (Personalities[i] == Personality)
return i;
}
// This will happen if the current personality function is
// in the zero index.
return 0;
}