124 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			124 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===-- BPFTargetMachine.cpp - Define TargetMachine for BPF ---------------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // Implements the info about BPF target spec.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "BPFTargetMachine.h"
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| #include "BPF.h"
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| #include "MCTargetDesc/BPFMCAsmInfo.h"
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| #include "llvm/CodeGen/Passes.h"
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| #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
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| #include "llvm/CodeGen/TargetPassConfig.h"
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| #include "llvm/IR/LegacyPassManager.h"
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| #include "llvm/Support/FormattedStream.h"
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| #include "llvm/Support/TargetRegistry.h"
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| #include "llvm/Target/TargetOptions.h"
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| using namespace llvm;
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| 
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| static cl::
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| opt<bool> DisableMIPeephole("disable-bpf-peephole", cl::Hidden,
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|                             cl::desc("Disable machine peepholes for BPF"));
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| 
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| extern "C" void LLVMInitializeBPFTarget() {
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|   // Register the target.
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|   RegisterTargetMachine<BPFTargetMachine> X(getTheBPFleTarget());
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|   RegisterTargetMachine<BPFTargetMachine> Y(getTheBPFbeTarget());
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|   RegisterTargetMachine<BPFTargetMachine> Z(getTheBPFTarget());
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| 
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|   PassRegistry &PR = *PassRegistry::getPassRegistry();
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|   initializeBPFMIPeepholePass(PR);
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| }
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| 
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| // DataLayout: little or big endian
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| static std::string computeDataLayout(const Triple &TT) {
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|   if (TT.getArch() == Triple::bpfeb)
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|     return "E-m:e-p:64:64-i64:64-n32:64-S128";
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|   else
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|     return "e-m:e-p:64:64-i64:64-n32:64-S128";
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| }
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| 
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| static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
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|   if (!RM.hasValue())
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|     return Reloc::PIC_;
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|   return *RM;
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| }
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| 
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| static CodeModel::Model getEffectiveCodeModel(Optional<CodeModel::Model> CM) {
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|   if (CM)
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|     return *CM;
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|   return CodeModel::Small;
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| }
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| 
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| BPFTargetMachine::BPFTargetMachine(const Target &T, const Triple &TT,
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|                                    StringRef CPU, StringRef FS,
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|                                    const TargetOptions &Options,
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|                                    Optional<Reloc::Model> RM,
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|                                    Optional<CodeModel::Model> CM,
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|                                    CodeGenOpt::Level OL, bool JIT)
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|     : LLVMTargetMachine(T, computeDataLayout(TT), TT, CPU, FS, Options,
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|                         getEffectiveRelocModel(RM), getEffectiveCodeModel(CM),
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|                         OL),
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|       TLOF(make_unique<TargetLoweringObjectFileELF>()),
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|       Subtarget(TT, CPU, FS, *this) {
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|   initAsmInfo();
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| 
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|   BPFMCAsmInfo *MAI =
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|       static_cast<BPFMCAsmInfo *>(const_cast<MCAsmInfo *>(AsmInfo.get()));
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|   MAI->setDwarfUsesRelocationsAcrossSections(!Subtarget.getUseDwarfRIS());
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| }
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| namespace {
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| // BPF Code Generator Pass Configuration Options.
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| class BPFPassConfig : public TargetPassConfig {
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| public:
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|   BPFPassConfig(BPFTargetMachine &TM, PassManagerBase &PM)
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|       : TargetPassConfig(TM, PM) {}
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| 
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|   BPFTargetMachine &getBPFTargetMachine() const {
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|     return getTM<BPFTargetMachine>();
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|   }
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| 
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|   bool addInstSelector() override;
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|   void addMachineSSAOptimization() override;
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|   void addPreEmitPass() override;
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| };
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| }
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| 
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| TargetPassConfig *BPFTargetMachine::createPassConfig(PassManagerBase &PM) {
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|   return new BPFPassConfig(*this, PM);
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| }
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| 
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| // Install an instruction selector pass using
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| // the ISelDag to gen BPF code.
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| bool BPFPassConfig::addInstSelector() {
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|   addPass(createBPFISelDag(getBPFTargetMachine()));
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| 
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|   return false;
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| }
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| 
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| void BPFPassConfig::addMachineSSAOptimization() {
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|   // The default implementation must be called first as we want eBPF
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|   // Peephole ran at last.
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|   TargetPassConfig::addMachineSSAOptimization();
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| 
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|   const BPFSubtarget *Subtarget = getBPFTargetMachine().getSubtargetImpl();
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|   if (Subtarget->getHasAlu32() && !DisableMIPeephole)
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|     addPass(createBPFMIPeepholePass());
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| }
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| 
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| void BPFPassConfig::addPreEmitPass() {
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|   const BPFSubtarget *Subtarget = getBPFTargetMachine().getSubtargetImpl();
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| 
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|   addPass(createBPFMIPreEmitCheckingPass());
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|   if (getOptLevel() != CodeGenOpt::None)
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|     if (Subtarget->getHasAlu32() && !DisableMIPeephole)
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|       addPass(createBPFMIPreEmitPeepholePass());
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| }
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