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Diffstat (limited to 'lib/CodeGen/MachineModuleInfo.cpp')
-rw-r--r-- | lib/CodeGen/MachineModuleInfo.cpp | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/lib/CodeGen/MachineModuleInfo.cpp b/lib/CodeGen/MachineModuleInfo.cpp new file mode 100644 index 0000000..1d8109e --- /dev/null +++ b/lib/CodeGen/MachineModuleInfo.cpp @@ -0,0 +1,368 @@ +//===-- 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/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/DerivedTypes.h" +#include "llvm/GlobalVariable.h" +#include "llvm/Intrinsics.h" +#include "llvm/Instructions.h" +#include "llvm/Module.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/Streams.h" +using namespace llvm; +using namespace llvm::dwarf; + +// Handle the Pass registration stuff necessary to use TargetData's. +static RegisterPass<MachineModuleInfo> +X("machinemoduleinfo", "Module Information"); +char MachineModuleInfo::ID = 0; + +//===----------------------------------------------------------------------===// + +MachineModuleInfo::MachineModuleInfo() +: ImmutablePass(&ID) +, LabelIDList() +, FrameMoves() +, LandingPads() +, Personalities() +, CallsEHReturn(0) +, CallsUnwindInit(0) +, DbgInfoAvailable(false) +{ + // Always emit "no personality" info + Personalities.push_back(NULL); +} +MachineModuleInfo::~MachineModuleInfo() { + +} + +/// doInitialization - Initialize the state for a new module. +/// +bool MachineModuleInfo::doInitialization() { + return false; +} + +/// doFinalization - Tear down the state after completion of a module. +/// +bool MachineModuleInfo::doFinalization() { + return false; +} + +/// BeginFunction - Begin gathering function meta information. +/// +void MachineModuleInfo::BeginFunction(MachineFunction *MF) { + // Coming soon. +} + +/// EndFunction - Discard function meta information. +/// +void MachineModuleInfo::EndFunction() { + // Clean up frame info. + FrameMoves.clear(); + + // Clean up exception info. + LandingPads.clear(); + TypeInfos.clear(); + FilterIds.clear(); + FilterEnds.clear(); + CallsEHReturn = 0; + CallsUnwindInit = 0; +} + +/// AnalyzeModule - Scan the module for global debug information. +/// +void MachineModuleInfo::AnalyzeModule(Module &M) { + // Insert functions in the llvm.used array into UsedFunctions. + GlobalVariable *GV = M.getGlobalVariable("llvm.used"); + if (!GV || !GV->hasInitializer()) return; + + // Should be an array of 'i8*'. + ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer()); + if (InitList == 0) return; + + for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { + if (ConstantExpr *CE = dyn_cast<ConstantExpr>(InitList->getOperand(i))) + if (CE->getOpcode() == Instruction::BitCast) + if (Function *F = dyn_cast<Function>(CE->getOperand(0))) + UsedFunctions.insert(F); + } +} + +//===-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, + unsigned BeginLabel, unsigned EndLabel) { + LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); + LP.BeginLabels.push_back(BeginLabel); + LP.EndLabels.push_back(EndLabel); +} + +/// addLandingPad - Provide the label of a try LandingPad block. +/// +unsigned MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) { + unsigned LandingPadLabel = NextLabelID(); + LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); + LP.LandingPadLabel = LandingPadLabel; + return LandingPadLabel; +} + +/// addPersonality - Provide the personality function for the exception +/// information. +void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad, + Function *Personality) { + LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); + LP.Personality = Personality; + + for (unsigned i = 0; i < Personalities.size(); ++i) + if (Personalities[i] == Personality) + return; + + Personalities.push_back(Personality); +} + +/// addCatchTypeInfo - Provide the catch typeinfo for a landing pad. +/// +void MachineModuleInfo::addCatchTypeInfo(MachineBasicBlock *LandingPad, + std::vector<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<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)); +} + +/// 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() { + for (unsigned i = 0; i != LandingPads.size(); ) { + LandingPadInfo &LandingPad = LandingPads[i]; + LandingPad.LandingPadLabel = MappedLabel(LandingPad.LandingPadLabel); + + // 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; + } + + for (unsigned j=0; j != LandingPads[i].BeginLabels.size(); ) { + unsigned BeginLabel = MappedLabel(LandingPad.BeginLabels[j]); + unsigned EndLabel = MappedLabel(LandingPad.EndLabels[j]); + + if (!BeginLabel || !EndLabel) { + LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j); + LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j); + continue; + } + + LandingPad.BeginLabels[j] = BeginLabel; + LandingPad.EndLabels[j] = EndLabel; + ++j; + } + + // Remove landing pads with no try-ranges. + if (LandingPads[i].BeginLabels.empty()) { + 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(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. +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 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 should never happen + assert(0 && "Personality function should be set!"); + return 0; +} + +//===----------------------------------------------------------------------===// +/// DebugLabelFolding pass - This pass prunes out redundant labels. This allows +/// a info consumer to determine if the range of two labels is empty, by seeing +/// if the labels map to the same reduced label. + +namespace llvm { + +struct DebugLabelFolder : public MachineFunctionPass { + static char ID; + DebugLabelFolder() : MachineFunctionPass(&ID) {} + + virtual void getAnalysisUsage(AnalysisUsage &AU) const { + AU.addPreservedID(MachineLoopInfoID); + AU.addPreservedID(MachineDominatorsID); + MachineFunctionPass::getAnalysisUsage(AU); + } + + virtual bool runOnMachineFunction(MachineFunction &MF); + virtual const char *getPassName() const { return "Label Folder"; } +}; + +char DebugLabelFolder::ID = 0; + +bool DebugLabelFolder::runOnMachineFunction(MachineFunction &MF) { + // Get machine module info. + MachineModuleInfo *MMI = getAnalysisIfAvailable<MachineModuleInfo>(); + if (!MMI) return false; + + // Track if change is made. + bool MadeChange = false; + // No prior label to begin. + unsigned PriorLabel = 0; + + // Iterate through basic blocks. + for (MachineFunction::iterator BB = MF.begin(), E = MF.end(); + BB != E; ++BB) { + // Iterate through instructions. + for (MachineBasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) { + // Is it a label. + if (I->isDebugLabel() && !MMI->isDbgLabelUsed(I->getOperand(0).getImm())){ + // The label ID # is always operand #0, an immediate. + unsigned NextLabel = I->getOperand(0).getImm(); + + // If there was an immediate prior label. + if (PriorLabel) { + // Remap the current label to prior label. + MMI->RemapLabel(NextLabel, PriorLabel); + // Delete the current label. + I = BB->erase(I); + // Indicate a change has been made. + MadeChange = true; + continue; + } else { + // Start a new round. + PriorLabel = NextLabel; + } + } else { + // No consecutive labels. + PriorLabel = 0; + } + + ++I; + } + } + + return MadeChange; +} + +FunctionPass *createDebugLabelFoldingPass() { return new DebugLabelFolder(); } + +} + |