1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155
|
//===-- BPFAsmPrinter.cpp - BPF LLVM assembly writer ----------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains a printer that converts from our internal representation
// of machine-dependent LLVM code to the BPF assembly language.
//
//===----------------------------------------------------------------------===//
#include "BPF.h"
#include "BPFInstrInfo.h"
#include "BPFMCInstLower.h"
#include "BPFTargetMachine.h"
#include "BTFDebug.h"
#include "MCTargetDesc/BPFInstPrinter.h"
#include "TargetInfo/BPFTargetInfo.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "asm-printer"
namespace {
class BPFAsmPrinter : public AsmPrinter {
public:
explicit BPFAsmPrinter(TargetMachine &TM,
std::unique_ptr<MCStreamer> Streamer)
: AsmPrinter(TM, std::move(Streamer)), BTF(nullptr) {}
StringRef getPassName() const override { return "BPF Assembly Printer"; }
bool doInitialization(Module &M) override;
void printOperand(const MachineInstr *MI, int OpNum, raw_ostream &O);
bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
const char *ExtraCode, raw_ostream &O) override;
bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum,
const char *ExtraCode, raw_ostream &O) override;
void EmitInstruction(const MachineInstr *MI) override;
private:
BTFDebug *BTF;
};
} // namespace
bool BPFAsmPrinter::doInitialization(Module &M) {
AsmPrinter::doInitialization(M);
// Only emit BTF when debuginfo available.
if (MAI->doesSupportDebugInformation() && !empty(M.debug_compile_units())) {
BTF = new BTFDebug(this);
Handlers.push_back(HandlerInfo(std::unique_ptr<BTFDebug>(BTF), "emit",
"Debug Info Emission", "BTF",
"BTF Emission"));
}
return false;
}
void BPFAsmPrinter::printOperand(const MachineInstr *MI, int OpNum,
raw_ostream &O) {
const MachineOperand &MO = MI->getOperand(OpNum);
switch (MO.getType()) {
case MachineOperand::MO_Register:
O << BPFInstPrinter::getRegisterName(MO.getReg());
break;
case MachineOperand::MO_Immediate:
O << MO.getImm();
break;
case MachineOperand::MO_MachineBasicBlock:
O << *MO.getMBB()->getSymbol();
break;
case MachineOperand::MO_GlobalAddress:
O << *getSymbol(MO.getGlobal());
break;
case MachineOperand::MO_BlockAddress: {
MCSymbol *BA = GetBlockAddressSymbol(MO.getBlockAddress());
O << BA->getName();
break;
}
case MachineOperand::MO_ExternalSymbol:
O << *GetExternalSymbolSymbol(MO.getSymbolName());
break;
case MachineOperand::MO_JumpTableIndex:
case MachineOperand::MO_ConstantPoolIndex:
default:
llvm_unreachable("<unknown operand type>");
}
}
bool BPFAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
const char *ExtraCode, raw_ostream &O) {
if (ExtraCode && ExtraCode[0])
return AsmPrinter::PrintAsmOperand(MI, OpNo, ExtraCode, O);
printOperand(MI, OpNo, O);
return false;
}
bool BPFAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
unsigned OpNum, const char *ExtraCode,
raw_ostream &O) {
assert(OpNum + 1 < MI->getNumOperands() && "Insufficient operands");
const MachineOperand &BaseMO = MI->getOperand(OpNum);
const MachineOperand &OffsetMO = MI->getOperand(OpNum + 1);
assert(BaseMO.isReg() && "Unexpected base pointer for inline asm memory operand.");
assert(OffsetMO.isImm() && "Unexpected offset for inline asm memory operand.");
int Offset = OffsetMO.getImm();
if (ExtraCode)
return true; // Unknown modifier.
if (Offset < 0)
O << "(" << BPFInstPrinter::getRegisterName(BaseMO.getReg()) << " - " << -Offset << ")";
else
O << "(" << BPFInstPrinter::getRegisterName(BaseMO.getReg()) << " + " << Offset << ")";
return false;
}
void BPFAsmPrinter::EmitInstruction(const MachineInstr *MI) {
MCInst TmpInst;
if (!BTF || !BTF->InstLower(MI, TmpInst)) {
BPFMCInstLower MCInstLowering(OutContext, *this);
MCInstLowering.Lower(MI, TmpInst);
}
EmitToStreamer(*OutStreamer, TmpInst);
}
// Force static initialization.
extern "C" void LLVMInitializeBPFAsmPrinter() {
RegisterAsmPrinter<BPFAsmPrinter> X(getTheBPFleTarget());
RegisterAsmPrinter<BPFAsmPrinter> Y(getTheBPFbeTarget());
RegisterAsmPrinter<BPFAsmPrinter> Z(getTheBPFTarget());
}
|